Anne Vincent-salomon - Academia.edu (original) (raw)

Papers by Anne Vincent-salomon

Research paper thumbnail of CD73-Mediated Immunosuppression Is Linked to a Specific Fibroblast Population That Paves the Way for New Therapy in Breast Cancer

Cancers, 2021

Background: Cancer-associated fibroblasts (CAF) are heterogeneous with multiple functions in brea... more Background: Cancer-associated fibroblasts (CAF) are heterogeneous with multiple functions in breast cancer. Recently, we identified a specific CAF subpopulation (referred to as CAF-S1), which promotes immunosuppression and immunotherapy resistance. Methods and Results: Here, by studying a large collection of human samples, we highlight the key function of CD73/NT5E in CAF-S1-mediated immunosuppression in breast cancer. We first reveal that CD73 protein level specifically accumulates in CAF-S1 in breast cancer patients. Interestingly, infiltration of regulatory T lymphocytes (Tregs) is significantly correlated with CD73 expression in stroma but not in epithelium, indicating that CD73 contributes to immunosuppression when expressed in CAF-S1 and not in tumor cells. By performing functional assays based on relevant systems using primary CAF-S1 isolated from patients, we demonstrate that CAF-S1 increase the content in both PD-1+ and CTLA-4+ Tregs. Importantly, the use of a blocking anti...

Research paper thumbnail of The Dilemma of HER2 Double-equivocal Breast Carcinomas: Genomic Profiling and Implications for Treatment

The American journal of surgical pathology, 2018

The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2013 guidel... more The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2013 guidelines for HER2 assessment have increased the number of HER2 equivocal breast carcinomas following in situ hybridization reflex testing, that is, HER2 "double equivocal" (equivocal protein expression and equivocal gene copy number). Forty-five double-equivocal carcinomas were subjected to Prosigna analysis. Twenty-seven cases were investigated for the expression of genes found to be differentially expressed between estrogen receptor (ER)-positive/HER2-positive (N=22) and ER-positive/HER2-negative (N=22) control cases. Twenty-nine of the 45 cases were also analyzed by targeted sequencing using a panel of 14 genes. We then explored the pathologic complete response rates in an independent series of double-equivocal carcinoma patients treated with trastuzumab-containing chemotherapy. All cases were ER-positive, with a mean Ki67 of 28%. Double-equivocal carcinomas were predominantly l...

Research paper thumbnail of High rate of PIK3CA mutations but no TP53 mutations in low-grade adenosquamous carcinoma of the breast

Histopathology, Jan 14, 2018

Low-grade adenosquamous carcinoma of the breast (LGASC) is a rare variant of metaplastic carcinom... more Low-grade adenosquamous carcinoma of the breast (LGASC) is a rare variant of metaplastic carcinoma characterised by a favourable outcome and histologically composed of glandular and squamous elements in a spindle cell background typically associated with a lymphocytic stromal reaction. Because of its rarity, the immunophenotypic and genetic profile of LGASC has not been sufficiently characterised. The aim of this study was to gain insights into the molecular and phenotypic characteristics of LGASC. We reviewed the clinical and morphological features and detailed the immunohistochemical characteristics of a retrospective series of 13 LGASCs. Targeted sequencing of 50 genes was performed in 10 of 13 cases. Identified mutations were further assessed by Sanger sequencing in a validation series of 11 additional cases. All tumours showed a triple-negative immunophenotype, expressed 'basal' keratins, showed variable levels of epidermal growth factor receptor expression, and did not...

Research paper thumbnail of Genomic and transcriptomic heterogeneity in metaplastic carcinomas of the breast

NPJ breast cancer, 2017

Metaplastic breast cancer (MBC) is a rare special histologic type of triple-negative breast cance... more Metaplastic breast cancer (MBC) is a rare special histologic type of triple-negative breast cancer, characterized by the presence of neoplastic cells showing differentiation towards squamous epithelium and/or mesenchymal elements. Here we sought to define whether histologically distinct subgroups of MBCs would be underpinned by distinct genomic and/or transcriptomic alterations. Microarray-based copy number profiling identified limited but significant differences between the distinct MBC subtypes studied here, despite the limited sample size (n = 17). In particular, we found that, compared to MBCs with chondroid or squamous cell metaplasia, MBCs with spindle cell differentiation less frequently harbored gain of 7q11.22-23 encompassing CLDN3 and CLDN4, consistent with their lower expression of claudins and their association with the claudin-low molecular classification. Microarray-based and RNA-sequencing-based gene expression profiling revealed that MBCs with spindle cell differenti...

Research paper thumbnail of The Landscape of Somatic Genetic Alterations in Metaplastic Breast Carcinomas

Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 2, 2017

Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic type of breast cancer pred... more Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic type of breast cancer predominantly of triple-negative phenotype, and characterized by the presence of malignant cells showing squamous and/or mesenchymal differentiation. We sought to define the repertoire of somatic genetic alterations and the mutational signatures of MBCs. Whole-exome sequencing was performed in 35 MBCs, with 16, ten and nine classified as harboring chondroid, spindle and squamous metaplasia as the predominant metaplastic component. The genomic landscape of MBCs was compared to that of triple-negative invasive ductal carcinomas of no special type (IDC-NSTs) from The Cancer Genome Atlas. Wnt pathway activity was assessed using a quantitative PCR assay. MBCs harbored complex genomes with frequent TP53 (69%) mutations. In contrast to triple-negative IDC-NSTs, MBCs more frequently harbored mutations in PIK3CA (29%), PIK3R1 (11%), ARID1A (11%), FAT1 (11%) and PTEN (11%). PIK3CA mutations were not f...

Research paper thumbnail of Breast cancer genome and transcriptome integration implicates specific mutational signatures with immune cell infiltration

Nature communications, Jan 26, 2016

A recent comprehensive whole genome analysis of a large breast cancer cohort was used to link kno... more A recent comprehensive whole genome analysis of a large breast cancer cohort was used to link known and novel drivers and substitution signatures to the transcriptome of 266 cases. Here, we validate that subtype-specific aberrations show concordant expression changes for, for example, TP53, PIK3CA, PTEN, CCND1 and CDH1. We find that CCND3 expression levels do not correlate with amplification, while increased GATA3 expression in mutant GATA3 cancers suggests GATA3 is an oncogene. In luminal cases the total number of substitutions, irrespective of type, associates with cell cycle gene expression and adverse outcome, whereas the number of mutations of signatures 3 and 13 associates with immune-response specific gene expression, increased numbers of tumour-infiltrating lymphocytes and better outcome. Thus, while earlier reports imply that the sheer number of somatic aberrations could trigger an immune-response, our data suggests that substitutions of a particular type are more effective...

Research paper thumbnail of Phyllodes tumours of the breast: a consensus review

Histopathology, 2015

Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Ac... more Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Accurate and reproducible grading of these tumours has long been challenging, owing to the need to assess multiple stratified histological parameters, which may be weighted differently by individual pathologists. Distinction of benign phyllodes tumours from cellular fibroadenomas is fraught with difficulty, due to overlapping microscopic features. Similarly, separation of the malignant phyllodes tumour from spindle cell metaplastic carcinoma and primary breast sarcoma can be problematic. Phyllodes tumours are treated by surgical excision. However, there is no consensus on the definition of an appropriate surgical margin to ensure completeness of excision and reduction of recurrence risk. Interpretive subjectivity, overlapping histological diagnostic criteria, suboptimal correlation between histological classification and clinical behaviour and the lack of robust molecular predictors of outcome make further investigation of the pathogenesis of these fascinating tumours a matter of active research. This review consolidates the current understanding of their pathobiology and clinical behaviour, and includes proposals for a rational approach to the classification and management of phyllodes tumours.

Research paper thumbnail of First description of a sporadic breast cancer in a woman with BRCA1 germline mutation

Oncotarget, 2015

We describe the case of a woman carrying a germline pathogenic BRCA1 mutation diagnosed with a br... more We describe the case of a woman carrying a germline pathogenic BRCA1 mutation diagnosed with a breast cancer overexpressing HER2. Clinical presentation of the tumor, HER2-positivity, genomic profile and loss of the mutated BRCA1 allele in tumor evidence that BRCA1 is not inactivated in this breast cancer. It represents the first biological demonstration for the existence of a sporadic HER2-positive breast cancer independent from BRCA loss of function in a woman carrier of a deleterious BRCA1 mutation. In a context where targeted therapies based on BRCA loss of function in the tumor are developed, such case could have direct implications.

Research paper thumbnail of Intra-tumor genetic heterogeneity and alternative driver genetic alterations in breast cancers with heterogeneous HER2 gene amplification

Genome Biology, 2015

Background: HER2 is overexpressed and amplified in approximately 15% of invasive breast cancers, ... more Background: HER2 is overexpressed and amplified in approximately 15% of invasive breast cancers, and is the molecular target and predictive marker of response to anti-HER2 agents. In a subset of these cases, heterogeneous distribution of HER2 gene amplification can be found, which creates clinically challenging scenarios. Currently, breast cancers with HER2 amplification/overexpression in just over 10% of cancer cells are considered HER2-positive for clinical purposes; however, it is unclear as to whether the HER2-negative components of such tumors would be driven by distinct genetic alterations. Here we sought to characterize the pathologic and genetic features of the HER2-positive and HER2-negative components of breast cancers with heterogeneous HER2 gene amplification and to define the repertoire of potential driver genetic alterations in the HER2-negative components of these cases. Results: We separately analyzed the HER2-negative and HER2-positive components of 12 HER2 heterogeneous breast cancers using gene copy number profiling and massively parallel sequencing, and identified potential driver genetic alterations restricted to the HER2-negative cells in each case. In vitro experiments provided functional evidence to suggest that BRF2 and DSN1 overexpression/amplification, and the HER2 I767M mutation may be alterations that compensate for the lack of HER2 amplification in the HER2-negative components of HER2 heterogeneous breast cancers. Conclusions: Our results indicate that even driver genetic alterations, such as HER2 gene amplification, can be heterogeneously distributed within a cancer, and that the HER2-negative components are likely driven by genetic alterations not present in the HER2-positive components, including BRF2 and DSN1 amplification and HER2 somatic mutations.

Research paper thumbnail of 225 Oxidative stress promotes myofibroblast differentiation and tumour spreading

European Journal of Cancer Supplements, 2010

JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative ... more JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative stress resulting from junD deletion to examine the role of reactive oxygen species (ROS) in tumour development. In a model of mammary carcinogenesis, junD inactivation increased tumour incidence and revealed an associated reactive stroma. junD-inactivation in the stroma was sufficient to shorten tumour-free survival rate and enhance metastatic spread. ROS promoted conversion of fibroblasts into highly migrating myofibroblasts through accumulation of the hypoxia-inducible factor (HIF)-1a transcription factor and the CXCL12 chemokine. Accordingly, treatment with an antioxidant reduced the levels of HIF and CXCL12 and numerous myofibroblast features. CXCL12 accumulated in the stroma of HER2-human breast adenocarcinomas. Moreover, HER2 tumours exhibited a high proportion of myofibroblasts, which was significantly correlated to nodal metastases. Interestingly, this subset of tumours exhibited a significant nuclear exclusion of JunD and revealed an associated oxido-reduction signature, further demonstrating the relevance of our findings in human cancers. Collectively, our data uncover a new mechanism by which oxidative stress increases the migratory properties of stromal fibroblasts, which in turn potentiate tumour dissemination.

Research paper thumbnail of High Ki67 expression is a risk marker of invasive relapse for classical lobular carcinoma in situ patients

Breast, 2012

Background: The clinical management of lobular carcinoma in situ lesions remains challenging. Our... more Background: The clinical management of lobular carcinoma in situ lesions remains challenging. Our aim was to evaluate the risk of relapse for lobular carcinoma in situ (LCIS) patients, diagnosed on mammography performed for microcalcifications and according to proliferation assessed by Ki67 staining. Methods: A series of 47 patient's files with LCIS and followed in our institution were retrospectively selected. All patients underwent lumpectomy without radiation therapy. The expression of E-cadherin, estrogen receptor (ER), progesterone receptor (PR), EGFR and Ki67 were determined. Four different classes were then defined with the following criteria: ERþ and Ki67 10%; ERþ, Ki67 > 10%; ERÀ; ER-PRÀ and EGFRþ. Results: Patient's mean age was 51.3 yrs. The majority of the lesions were classical LCIS (97%). All cases were E-cadherin either negative (71%) or weak and incomplete (29%). Among the 44 evaluable cases, 34 cases were ER or PR positive with KI67 10% (79%), 9 cases ER positive with KI67 > 10% (21%), 1 case was ER and PR negative and expressed EGFR. At five years, all patients were alive, 1/34 ER positive and Ki67 low experienced a relapse contrasting with 3 out of 9 ER positive and Ki67 high (3 invasive carcinomas including 2 ductal and 1 lobular) (p ¼ 0.0054). Conclusion: In this retrospective study, we observed a higher risk of relapse associated with a high proliferative activity of classical LCIS. If confirmed in larger series, this observation suggests that radiation therapy or hormonotherapy could be discussed for patients with Ki67 high classical LCIS in order to decrease their risk of relapse.

Research paper thumbnail of Inverted Apical CD24 and Weak EZH2 Expressions Are Phenotypic Characteristics of Pure Invasive Micropapillary Carcinoma of the Breast

Open Journal of Pathology, 2013

Invasive micropapillary carcinomas (IMPC) of the breast account for less than 2% of all breast ca... more Invasive micropapillary carcinomas (IMPC) of the breast account for less than 2% of all breast cancers and have been recently described as luminal B carcinomas. CD24, CD44, ALDH1 and EZH2 are commonly used as stem-cell markers that display differential expression as a function of stage and molecular type, but their pattern of expression according to this rare histological type remains poorly defined and unknown for EZH2. We assessed expression of these markers in a series of 28 micropapillary breast carcinomas and compared the results with those obtained in a series of luminal A (27 cases) and B (34 cases) invasive carcinomas of no special type (IC-NST). CD24 and CD44 were expressed in most cases. However, CD24 was expressed at the inverted apical membrane in 85% of invasive micropapillary carcinoma and at the apical pole of gland-forming cells in 45% of luminal A (p-val = 6.8  10 −4) and 13% of luminal B cases (p-val = 1.1  10 −7). ALDH1 was expressed in the stroma in most tumors, but in only 25%, 11% and 15% in epithelial cells of IMPC, luminal A and B IC-NST, respectively. Nuclear expression of EZH2 was not observed in luminal A tumors, and was detected in 35% (12/34) of luminal B carcinomas (p-val = 6.1  10 −3) and only 4% (1/28) of invasive micropapillary carcinomas. This series shows that invasive micropapillary carcinomas harbor a CD24-positive inverted apical pole associated with weak EZH2 expression, phenotypical characteristics that distinguish this entity from other luminal carcinomas.

Research paper thumbnail of 8p22 MTUS1 Gene Product ATIP3 Is a Novel Anti-Mitotic Protein Underexpressed in Invasive Breast Carcinoma of Poor Prognosis

PLoS ONE, 2009

Background: Breast cancer is a heterogeneous disease that is not totally eradicated by current th... more Background: Breast cancer is a heterogeneous disease that is not totally eradicated by current therapies. The classification of breast tumors into distinct molecular subtypes by gene profiling and immunodetection of surrogate markers has proven useful for tumor prognosis and prediction of effective targeted treatments. The challenge now is to identify molecular biomarkers that may be of functional relevance for personalized therapy of breast tumors with poor outcome that do not respond to available treatments. The Mitochondrial Tumor Suppressor (MTUS1) gene is an interesting candidate whose expression is reduced in colon, pancreas, ovary and oral cancers. The present study investigates the expression and functional effects of MTUS1 gene products in breast cancer. Methods and Findings: By means of gene array analysis, real-time RT-PCR and immunohistochemistry, we show here that MTUS1/ATIP3 is significantly down-regulated in a series of 151 infiltrating breast cancer carcinomas as compared to normal breast tissue. Low levels of ATIP3 correlate with high grade of the tumor and the occurrence of distant metastasis. ATIP3 levels are also significantly reduced in triple negative (ER-PR-HER2-) breast carcinomas, a subgroup of highly proliferative tumors with poor outcome and no available targeted therapy. Functional studies indicate that silencing ATIP3 expression by siRNA increases breast cancer cell proliferation. Conversely, restoring endogenous levels of ATIP3 expression leads to reduced cancer cell proliferation, clonogenicity, anchorage-independent growth, and reduces the incidence and size of xenografts grown in vivo. We provide evidence that ATIP3 associates with the microtubule cytoskeleton and localizes at the centrosomes, mitotic spindle and intercellular bridge during cell division. Accordingly, live cell imaging indicates that ATIP3 expression alters the progression of cell division by promoting prolonged metaphase, thereby leading to a reduced number of cells ungergoing active mitosis. Conclusions: Our results identify for the first time ATIP3 as a novel microtubule-associated protein whose expression is significantly reduced in highly proliferative breast carcinomas of poor clinical outcome. ATIP3 re-expression limits tumor cell proliferation in vitro and in vivo, suggesting that this protein may represent a novel useful biomarker and an interesting candidate for future targeted therapies of aggressive breast cancer.

Research paper thumbnail of Strong Correlation between Results of Fluorescent In Situ Hybridization and Immunohistochemistry for the Assessment of the ERBB2 (HER-2/neu) Gene Status in Breast Carcinoma

Modern Pathology, 2000

ERBB2 (HER-2/neu) amplification and/or overexpression are associated with poor prognosis in node-... more ERBB2 (HER-2/neu) amplification and/or overexpression are associated with poor prognosis in node-positive breast carcinoma. Its prognostic value in node-negative cases and its predictive value for response to chemotherapy remain controversial. This may be related to the use of molecular methods, which are sensitive to dilution of tumor material by normal cells, or the use of nonstandardized immunohistochemistry (IHC) procedures, for the determination of the ERBB2 gene status. In addition, new therapeutic approaches that target the cells overexpressing ERBB2 are under development. These perspectives necessitate a reliable evaluation of the status of ERBB2 in individual tumors before the application of specific therapeutic strategies. Fluorescent in situ hybridization (FISH) and IHC allow the evaluation of the ERBB2 status specifically in tumor cells on archival material. We have analyzed a series of 100 invasive ductal breast carcinomas without lymph node invasion both by IHC, using the CB11 monoclonal antibody and a sensitive Auidin Biotin Complex (ABC) immunodetection system, and by FISH, using the Oncor Inform HER-2/neu (ERBB2) gene amplification detection system as reference technique. Complete concordance between the results of FISH and IHC was seen in 98% of the cases. ERBB2 amplification (more than four signals per nucleus) was observed in 12 of the 100 cases, and all but one showed an overexpression of the protein (membrane staining) by IHC. Conversely, ERBB2 expression was present in one case without gene amplification. In conclusion, ERBB2 overexpression detected by IHC is highly correlated to gene amplification detected by FISH. Thus, under standardized conditions, IHC is a reliable and economical test to assess the ERBB2 status in tumors. The use of FISH could be limited to the verification of the status of tumors displaying a weak membrane immunostaining.

Research paper thumbnail of Secretory breast carcinomas with ETV6-NTRK3 fusion gene belong to the basal-like carcinoma spectrum

Modern Pathology, 2008

Secretory breast carcinomas (o0.15% of breast tumors) are associated with a characteristic morpho... more Secretory breast carcinomas (o0.15% of breast tumors) are associated with a characteristic morphology and a favorable prognosis. Remarkably, this entity is the only epithelial tumor of the breast with a balanced translocation, t(12;15), that creates an ETV6-NTRK3 gene fusion encoding chimeric tyrosine kinase also encountered in cellular mesoblastic nephroma and infantile fibrosarcoma. The aim of this study was to determine the phenotypic class (ie luminal A/B, ERBB2, basal-like) of secretory breast carcinoma. A series of six secretory breast carcinomas were identified in our files. The ETV6 rearrangement was confirmed in all cases by fluorescence in situ hybridization. Immunophenotype was assessed with anti-ER, PR, ERBB2, KIT, EGFR, E-cadherin, vimentin, PS100, smooth muscle actin, basal (CK5/6 and 14), luminal cytokeratins (CK8/18) and p63 antibodies. In situ and invasive components shared the same immunoprofile and were ER, PR, ERBB2 negative with expression of basal cytokeratins. ETV6 gene alterations were present in both in situ and invasive components, highlighting their genetic similarities. The immunoprofile data (triple-negative with expression of basal markers) showed that secretory breast carcinomas with ETV6-NTRK3 fusion gene belong to the phenotypic basal-like spectrum of breast carcinomas. These results support the hypothesis that secretory breast carcinomas have immunohistochemical and genetic features that distinguish them from other basal-like tumors of the breast.

Research paper thumbnail of Overexpression/Amplification of HER-2/neu is Uncommon in Invasive Carcinoma of the Uterine Cervix

International Journal of Gynecological Pathology, 2004

The aim of this study was to investigate HER-2/neu (c-erbB2) overexpression/amplification in carc... more The aim of this study was to investigate HER-2/neu (c-erbB2) overexpression/amplification in carcinoma of the uterine cervix using immunohistochemistry and fluorescent in situ hybridization (FISH) to assess whether anti-p185c-erbB2 therapy might have potential benefits in patients with advanced invasive cervical carcinoma. The authors used a protocol for p185c-erbB2 immunohistochemistry (clone CB11) that has been previously calibrated using FISH as the gold standard, showing a 98% accuracy rate in a large series of breast carcinomas. Immunolabeling for p185c-erbB2 was present in 24 of 82 (29%) of the tumors, but only 2 tumors (2%) with a labeling of more than 60% of the cells were considered positive for overexpression. FISH analysis did not find HER-2/neu gene amplification in these cases, although five other tumors showed weak and/or focal immunolabeling. There was no correlation between the presence of immunolabeling and age, histologic type, or clinical stage. Overexpression/amplification of HER-2/neu is uncommon in invasive cervical carcinoma, suggesting that there is little indication for using anti-p185c-erbB2 therapy in the treatment of these patients.

Research paper thumbnail of Oxidative stress promotes myofibroblast differentiation and tumour spreading

EMBO Molecular Medicine, 2010

JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative ... more JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative stress resulting from junD deletion to examine the role of reactive oxygen species (ROS) in tumour development. In a model of mammary carcinogenesis, junD inactivation increased tumour incidence and revealed an associated reactive stroma. junD-inactivation in the stroma was sufficient to shorten tumour-free survival rate and enhance metastatic spread. ROS promoted conversion of fibroblasts into highly migrating myofibroblasts through accumulation of the hypoxia-inducible factor (HIF)-1a transcription factor and the CXCL12 chemokine. Accordingly, treatment with an antioxidant reduced the levels of HIF and CXCL12 and numerous myofibroblast features. CXCL12 accumulated in the stroma of HER2-human breast adenocarcinomas. Moreover, HER2 tumours exhibited a high proportion of myofibroblasts, which was significantly correlated to nodal metastases. Interestingly, this subset of tumours exhibited a significant nuclear exclusion of JunD and revealed an associated oxido-reduction signature, further demonstrating the relevance of our findings in human cancers. Collectively, our data uncover a new mechanism by which oxidative stress increases the migratory properties of stromal fibroblasts, which in turn potentiate tumour dissemination.

Research paper thumbnail of Characterization of the Recurrent 8p11-12 Amplicon Identifies PPAPDC1B, a Phosphatase Protein, as a New Therapeutic Target in Breast Cancer

Cancer Research, 2008

The 8p11-12 chromosome region is one of the regions most frequently amplified in breast carcinoma... more The 8p11-12 chromosome region is one of the regions most frequently amplified in breast carcinoma (10–15% of cases). Several genes within this region have been identified as candidate oncogenes, as they are both amplified and overexpressed. However, very few studies have explored the role of these genes in cell transformation, with the aim of identifying valuable therapeutic targets. An analysis of comparative genomic hybridization array and expression profiling data for a series of 152 ductal breast carcinomas and 21 cell lines identified five genes (LSM1, BAG4, DDHD2, PPAPDC1B, and WHSC1L1) within the amplified region as consistently overexpressed due to an increased gene copy number. The use of small interfering RNA to knock down the expression of each of these genes showed the major role played by two genes, PPAPDC1B and WHSC1L1, in regulating the survival and transformation of two different cell lines harboring the 8p amplicon. The role of these two genes in cell survival and c...

Research paper thumbnail of High Frequency of TP53 Mutation in BRCA1 and Sporadic Basal-like Carcinomas but not in BRCA1 Luminal Breast Tumors

Cancer Research, 2009

Breast tumors with a germ-line mutation of BRCA1 (BRCA1 tumors) and basal-like carcinoma (BLC) ar... more Breast tumors with a germ-line mutation of BRCA1 (BRCA1 tumors) and basal-like carcinoma (BLC) are associated with a high rate of TP53 mutation. Because BRCA1 tumors frequently display a basal-like phenotype, this study was designed to determine whether TP53 mutations are correlated with the hereditary BRCA1 mutated status or the particular phenotype of these tumors. The TP53 gene status was first investigated in a series of 35 BRCA1 BLCs using immunohistochemistry, direct sequencing of the coding sequence, and functional analysis of separated alleles in yeast, and compared with the TP53 status in a series of 38 sporadic (nonhereditary) BLCs. Using this sensitive approach, TP53 was found to be frequently mutated in both BRCA1 (34 of 35, 97%) and sporadic (35 of 38, 92%) BLCs. However, the spectrum of mutation was different, particularly with a higher rate of complex mutations, such as insertion/deletion, in BRCA1 BLCs than in the sporadic group [14 of 33 (42%) and 13 of 34 (9%), res...

Research paper thumbnail of Identification of typical medullary breast carcinoma as a genomic sub-group of basal-like carcinomas, a heterogeneous new molecular entity

Breast Cancer Research, 2007

Introduction Typical medullary breast carcinoma (MBC) has recently been recognized to be part of ... more Introduction Typical medullary breast carcinoma (MBC) has recently been recognized to be part of the basal-like carcinoma spectrum, a feature in agreement with the high rate of TP53 mutations previously reported in MBCs. The present study was therefore designed to identify phenotypic and genetic alterations that distinguish MBCs from basal-like carcinomas (BLC). Methods Expression levels of estrogen receptor (ER), progesterone receptor (PR), ERBB2, TP53, cytokeratins (KRTs) 5/6, 14, 8/18, epidermal growth factor receptor and KIT, as well as TP53 gene sequence and high-density array comparative genomic hybridization (CGH) profiles, were assessed and compared in a series of 33 MBCs and 26 BLCs. Results All tumors were negative for ER, PR and ERBB2. KRTs 5/6 were more frequently expressed in MBCs (94%) than in BLCs (56%) (p = 0.0004). TP53 mutations were disclosed in 20/26 MBCs (77%) and 20/24 BLCs (83%). Array CGH analysis showed that a higher number of gains (95 regions) and losses (34 regions) was observed in MBCs than in BLCs (36 regions of gain; 13 regions of losses). In addition, gains of 1q and 8q, and losses of X were found to be common to the two groups, whereas gains of 10p (53% of the cases), 9p (30.8% of the cases) and 16q (25.8% of the cases), and losses of 4p (34.8% of the cases), and amplicons of 1q, 8p, 10p and 12p were the genetic alterations found to characterize MBC. Conclusion Our study has revealed that MBCs are part of the basal-like group and share common genomic alterations with BLCs, the most frequent being 1q and 8q gains and X losses; however, MBCs are a distinct entity within the basal-like spectrum, characterized by a higher rate of KRT 5/6 expression, a higher rate of gains and losses than BLCs, recurrent 10p, 9p and 16q gains, 4p losses, and 1q, 8p, 10p and 12p amplicons. Our results thus contribute to a better understanding of the heterogeneity in basal-like breast tumors and provide potential diagnostic tools. aCGH = array comparative genomic hybridization; BAC = bacterial artificial chromosome; BLC = basal-like carcinoma; ER = estrogen receptor; FISH = fluorescence in situ hybridization; KRT = cytokeratin; MBC = medullary breast carcinoma; PAC = P1-derived artificial chromosome; PR = progesterone receptor; SSC = standard saline citrate.

Research paper thumbnail of CD73-Mediated Immunosuppression Is Linked to a Specific Fibroblast Population That Paves the Way for New Therapy in Breast Cancer

Cancers, 2021

Background: Cancer-associated fibroblasts (CAF) are heterogeneous with multiple functions in brea... more Background: Cancer-associated fibroblasts (CAF) are heterogeneous with multiple functions in breast cancer. Recently, we identified a specific CAF subpopulation (referred to as CAF-S1), which promotes immunosuppression and immunotherapy resistance. Methods and Results: Here, by studying a large collection of human samples, we highlight the key function of CD73/NT5E in CAF-S1-mediated immunosuppression in breast cancer. We first reveal that CD73 protein level specifically accumulates in CAF-S1 in breast cancer patients. Interestingly, infiltration of regulatory T lymphocytes (Tregs) is significantly correlated with CD73 expression in stroma but not in epithelium, indicating that CD73 contributes to immunosuppression when expressed in CAF-S1 and not in tumor cells. By performing functional assays based on relevant systems using primary CAF-S1 isolated from patients, we demonstrate that CAF-S1 increase the content in both PD-1+ and CTLA-4+ Tregs. Importantly, the use of a blocking anti...

Research paper thumbnail of The Dilemma of HER2 Double-equivocal Breast Carcinomas: Genomic Profiling and Implications for Treatment

The American journal of surgical pathology, 2018

The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2013 guidel... more The American Society of Clinical Oncology/College of American Pathologists (ASCO/CAP) 2013 guidelines for HER2 assessment have increased the number of HER2 equivocal breast carcinomas following in situ hybridization reflex testing, that is, HER2 "double equivocal" (equivocal protein expression and equivocal gene copy number). Forty-five double-equivocal carcinomas were subjected to Prosigna analysis. Twenty-seven cases were investigated for the expression of genes found to be differentially expressed between estrogen receptor (ER)-positive/HER2-positive (N=22) and ER-positive/HER2-negative (N=22) control cases. Twenty-nine of the 45 cases were also analyzed by targeted sequencing using a panel of 14 genes. We then explored the pathologic complete response rates in an independent series of double-equivocal carcinoma patients treated with trastuzumab-containing chemotherapy. All cases were ER-positive, with a mean Ki67 of 28%. Double-equivocal carcinomas were predominantly l...

Research paper thumbnail of High rate of PIK3CA mutations but no TP53 mutations in low-grade adenosquamous carcinoma of the breast

Histopathology, Jan 14, 2018

Low-grade adenosquamous carcinoma of the breast (LGASC) is a rare variant of metaplastic carcinom... more Low-grade adenosquamous carcinoma of the breast (LGASC) is a rare variant of metaplastic carcinoma characterised by a favourable outcome and histologically composed of glandular and squamous elements in a spindle cell background typically associated with a lymphocytic stromal reaction. Because of its rarity, the immunophenotypic and genetic profile of LGASC has not been sufficiently characterised. The aim of this study was to gain insights into the molecular and phenotypic characteristics of LGASC. We reviewed the clinical and morphological features and detailed the immunohistochemical characteristics of a retrospective series of 13 LGASCs. Targeted sequencing of 50 genes was performed in 10 of 13 cases. Identified mutations were further assessed by Sanger sequencing in a validation series of 11 additional cases. All tumours showed a triple-negative immunophenotype, expressed 'basal' keratins, showed variable levels of epidermal growth factor receptor expression, and did not...

Research paper thumbnail of Genomic and transcriptomic heterogeneity in metaplastic carcinomas of the breast

NPJ breast cancer, 2017

Metaplastic breast cancer (MBC) is a rare special histologic type of triple-negative breast cance... more Metaplastic breast cancer (MBC) is a rare special histologic type of triple-negative breast cancer, characterized by the presence of neoplastic cells showing differentiation towards squamous epithelium and/or mesenchymal elements. Here we sought to define whether histologically distinct subgroups of MBCs would be underpinned by distinct genomic and/or transcriptomic alterations. Microarray-based copy number profiling identified limited but significant differences between the distinct MBC subtypes studied here, despite the limited sample size (n = 17). In particular, we found that, compared to MBCs with chondroid or squamous cell metaplasia, MBCs with spindle cell differentiation less frequently harbored gain of 7q11.22-23 encompassing CLDN3 and CLDN4, consistent with their lower expression of claudins and their association with the claudin-low molecular classification. Microarray-based and RNA-sequencing-based gene expression profiling revealed that MBCs with spindle cell differenti...

Research paper thumbnail of The Landscape of Somatic Genetic Alterations in Metaplastic Breast Carcinomas

Clinical cancer research : an official journal of the American Association for Cancer Research, Jan 2, 2017

Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic type of breast cancer pred... more Metaplastic breast carcinoma (MBC) is a rare and aggressive histologic type of breast cancer predominantly of triple-negative phenotype, and characterized by the presence of malignant cells showing squamous and/or mesenchymal differentiation. We sought to define the repertoire of somatic genetic alterations and the mutational signatures of MBCs. Whole-exome sequencing was performed in 35 MBCs, with 16, ten and nine classified as harboring chondroid, spindle and squamous metaplasia as the predominant metaplastic component. The genomic landscape of MBCs was compared to that of triple-negative invasive ductal carcinomas of no special type (IDC-NSTs) from The Cancer Genome Atlas. Wnt pathway activity was assessed using a quantitative PCR assay. MBCs harbored complex genomes with frequent TP53 (69%) mutations. In contrast to triple-negative IDC-NSTs, MBCs more frequently harbored mutations in PIK3CA (29%), PIK3R1 (11%), ARID1A (11%), FAT1 (11%) and PTEN (11%). PIK3CA mutations were not f...

Research paper thumbnail of Breast cancer genome and transcriptome integration implicates specific mutational signatures with immune cell infiltration

Nature communications, Jan 26, 2016

A recent comprehensive whole genome analysis of a large breast cancer cohort was used to link kno... more A recent comprehensive whole genome analysis of a large breast cancer cohort was used to link known and novel drivers and substitution signatures to the transcriptome of 266 cases. Here, we validate that subtype-specific aberrations show concordant expression changes for, for example, TP53, PIK3CA, PTEN, CCND1 and CDH1. We find that CCND3 expression levels do not correlate with amplification, while increased GATA3 expression in mutant GATA3 cancers suggests GATA3 is an oncogene. In luminal cases the total number of substitutions, irrespective of type, associates with cell cycle gene expression and adverse outcome, whereas the number of mutations of signatures 3 and 13 associates with immune-response specific gene expression, increased numbers of tumour-infiltrating lymphocytes and better outcome. Thus, while earlier reports imply that the sheer number of somatic aberrations could trigger an immune-response, our data suggests that substitutions of a particular type are more effective...

Research paper thumbnail of Phyllodes tumours of the breast: a consensus review

Histopathology, 2015

Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Ac... more Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Accurate and reproducible grading of these tumours has long been challenging, owing to the need to assess multiple stratified histological parameters, which may be weighted differently by individual pathologists. Distinction of benign phyllodes tumours from cellular fibroadenomas is fraught with difficulty, due to overlapping microscopic features. Similarly, separation of the malignant phyllodes tumour from spindle cell metaplastic carcinoma and primary breast sarcoma can be problematic. Phyllodes tumours are treated by surgical excision. However, there is no consensus on the definition of an appropriate surgical margin to ensure completeness of excision and reduction of recurrence risk. Interpretive subjectivity, overlapping histological diagnostic criteria, suboptimal correlation between histological classification and clinical behaviour and the lack of robust molecular predictors of outcome make further investigation of the pathogenesis of these fascinating tumours a matter of active research. This review consolidates the current understanding of their pathobiology and clinical behaviour, and includes proposals for a rational approach to the classification and management of phyllodes tumours.

Research paper thumbnail of First description of a sporadic breast cancer in a woman with BRCA1 germline mutation

Oncotarget, 2015

We describe the case of a woman carrying a germline pathogenic BRCA1 mutation diagnosed with a br... more We describe the case of a woman carrying a germline pathogenic BRCA1 mutation diagnosed with a breast cancer overexpressing HER2. Clinical presentation of the tumor, HER2-positivity, genomic profile and loss of the mutated BRCA1 allele in tumor evidence that BRCA1 is not inactivated in this breast cancer. It represents the first biological demonstration for the existence of a sporadic HER2-positive breast cancer independent from BRCA loss of function in a woman carrier of a deleterious BRCA1 mutation. In a context where targeted therapies based on BRCA loss of function in the tumor are developed, such case could have direct implications.

Research paper thumbnail of Intra-tumor genetic heterogeneity and alternative driver genetic alterations in breast cancers with heterogeneous HER2 gene amplification

Genome Biology, 2015

Background: HER2 is overexpressed and amplified in approximately 15% of invasive breast cancers, ... more Background: HER2 is overexpressed and amplified in approximately 15% of invasive breast cancers, and is the molecular target and predictive marker of response to anti-HER2 agents. In a subset of these cases, heterogeneous distribution of HER2 gene amplification can be found, which creates clinically challenging scenarios. Currently, breast cancers with HER2 amplification/overexpression in just over 10% of cancer cells are considered HER2-positive for clinical purposes; however, it is unclear as to whether the HER2-negative components of such tumors would be driven by distinct genetic alterations. Here we sought to characterize the pathologic and genetic features of the HER2-positive and HER2-negative components of breast cancers with heterogeneous HER2 gene amplification and to define the repertoire of potential driver genetic alterations in the HER2-negative components of these cases. Results: We separately analyzed the HER2-negative and HER2-positive components of 12 HER2 heterogeneous breast cancers using gene copy number profiling and massively parallel sequencing, and identified potential driver genetic alterations restricted to the HER2-negative cells in each case. In vitro experiments provided functional evidence to suggest that BRF2 and DSN1 overexpression/amplification, and the HER2 I767M mutation may be alterations that compensate for the lack of HER2 amplification in the HER2-negative components of HER2 heterogeneous breast cancers. Conclusions: Our results indicate that even driver genetic alterations, such as HER2 gene amplification, can be heterogeneously distributed within a cancer, and that the HER2-negative components are likely driven by genetic alterations not present in the HER2-positive components, including BRF2 and DSN1 amplification and HER2 somatic mutations.

Research paper thumbnail of 225 Oxidative stress promotes myofibroblast differentiation and tumour spreading

European Journal of Cancer Supplements, 2010

JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative ... more JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative stress resulting from junD deletion to examine the role of reactive oxygen species (ROS) in tumour development. In a model of mammary carcinogenesis, junD inactivation increased tumour incidence and revealed an associated reactive stroma. junD-inactivation in the stroma was sufficient to shorten tumour-free survival rate and enhance metastatic spread. ROS promoted conversion of fibroblasts into highly migrating myofibroblasts through accumulation of the hypoxia-inducible factor (HIF)-1a transcription factor and the CXCL12 chemokine. Accordingly, treatment with an antioxidant reduced the levels of HIF and CXCL12 and numerous myofibroblast features. CXCL12 accumulated in the stroma of HER2-human breast adenocarcinomas. Moreover, HER2 tumours exhibited a high proportion of myofibroblasts, which was significantly correlated to nodal metastases. Interestingly, this subset of tumours exhibited a significant nuclear exclusion of JunD and revealed an associated oxido-reduction signature, further demonstrating the relevance of our findings in human cancers. Collectively, our data uncover a new mechanism by which oxidative stress increases the migratory properties of stromal fibroblasts, which in turn potentiate tumour dissemination.

Research paper thumbnail of High Ki67 expression is a risk marker of invasive relapse for classical lobular carcinoma in situ patients

Breast, 2012

Background: The clinical management of lobular carcinoma in situ lesions remains challenging. Our... more Background: The clinical management of lobular carcinoma in situ lesions remains challenging. Our aim was to evaluate the risk of relapse for lobular carcinoma in situ (LCIS) patients, diagnosed on mammography performed for microcalcifications and according to proliferation assessed by Ki67 staining. Methods: A series of 47 patient's files with LCIS and followed in our institution were retrospectively selected. All patients underwent lumpectomy without radiation therapy. The expression of E-cadherin, estrogen receptor (ER), progesterone receptor (PR), EGFR and Ki67 were determined. Four different classes were then defined with the following criteria: ERþ and Ki67 10%; ERþ, Ki67 > 10%; ERÀ; ER-PRÀ and EGFRþ. Results: Patient's mean age was 51.3 yrs. The majority of the lesions were classical LCIS (97%). All cases were E-cadherin either negative (71%) or weak and incomplete (29%). Among the 44 evaluable cases, 34 cases were ER or PR positive with KI67 10% (79%), 9 cases ER positive with KI67 > 10% (21%), 1 case was ER and PR negative and expressed EGFR. At five years, all patients were alive, 1/34 ER positive and Ki67 low experienced a relapse contrasting with 3 out of 9 ER positive and Ki67 high (3 invasive carcinomas including 2 ductal and 1 lobular) (p ¼ 0.0054). Conclusion: In this retrospective study, we observed a higher risk of relapse associated with a high proliferative activity of classical LCIS. If confirmed in larger series, this observation suggests that radiation therapy or hormonotherapy could be discussed for patients with Ki67 high classical LCIS in order to decrease their risk of relapse.

Research paper thumbnail of Inverted Apical CD24 and Weak EZH2 Expressions Are Phenotypic Characteristics of Pure Invasive Micropapillary Carcinoma of the Breast

Open Journal of Pathology, 2013

Invasive micropapillary carcinomas (IMPC) of the breast account for less than 2% of all breast ca... more Invasive micropapillary carcinomas (IMPC) of the breast account for less than 2% of all breast cancers and have been recently described as luminal B carcinomas. CD24, CD44, ALDH1 and EZH2 are commonly used as stem-cell markers that display differential expression as a function of stage and molecular type, but their pattern of expression according to this rare histological type remains poorly defined and unknown for EZH2. We assessed expression of these markers in a series of 28 micropapillary breast carcinomas and compared the results with those obtained in a series of luminal A (27 cases) and B (34 cases) invasive carcinomas of no special type (IC-NST). CD24 and CD44 were expressed in most cases. However, CD24 was expressed at the inverted apical membrane in 85% of invasive micropapillary carcinoma and at the apical pole of gland-forming cells in 45% of luminal A (p-val = 6.8  10 −4) and 13% of luminal B cases (p-val = 1.1  10 −7). ALDH1 was expressed in the stroma in most tumors, but in only 25%, 11% and 15% in epithelial cells of IMPC, luminal A and B IC-NST, respectively. Nuclear expression of EZH2 was not observed in luminal A tumors, and was detected in 35% (12/34) of luminal B carcinomas (p-val = 6.1  10 −3) and only 4% (1/28) of invasive micropapillary carcinomas. This series shows that invasive micropapillary carcinomas harbor a CD24-positive inverted apical pole associated with weak EZH2 expression, phenotypical characteristics that distinguish this entity from other luminal carcinomas.

Research paper thumbnail of 8p22 MTUS1 Gene Product ATIP3 Is a Novel Anti-Mitotic Protein Underexpressed in Invasive Breast Carcinoma of Poor Prognosis

PLoS ONE, 2009

Background: Breast cancer is a heterogeneous disease that is not totally eradicated by current th... more Background: Breast cancer is a heterogeneous disease that is not totally eradicated by current therapies. The classification of breast tumors into distinct molecular subtypes by gene profiling and immunodetection of surrogate markers has proven useful for tumor prognosis and prediction of effective targeted treatments. The challenge now is to identify molecular biomarkers that may be of functional relevance for personalized therapy of breast tumors with poor outcome that do not respond to available treatments. The Mitochondrial Tumor Suppressor (MTUS1) gene is an interesting candidate whose expression is reduced in colon, pancreas, ovary and oral cancers. The present study investigates the expression and functional effects of MTUS1 gene products in breast cancer. Methods and Findings: By means of gene array analysis, real-time RT-PCR and immunohistochemistry, we show here that MTUS1/ATIP3 is significantly down-regulated in a series of 151 infiltrating breast cancer carcinomas as compared to normal breast tissue. Low levels of ATIP3 correlate with high grade of the tumor and the occurrence of distant metastasis. ATIP3 levels are also significantly reduced in triple negative (ER-PR-HER2-) breast carcinomas, a subgroup of highly proliferative tumors with poor outcome and no available targeted therapy. Functional studies indicate that silencing ATIP3 expression by siRNA increases breast cancer cell proliferation. Conversely, restoring endogenous levels of ATIP3 expression leads to reduced cancer cell proliferation, clonogenicity, anchorage-independent growth, and reduces the incidence and size of xenografts grown in vivo. We provide evidence that ATIP3 associates with the microtubule cytoskeleton and localizes at the centrosomes, mitotic spindle and intercellular bridge during cell division. Accordingly, live cell imaging indicates that ATIP3 expression alters the progression of cell division by promoting prolonged metaphase, thereby leading to a reduced number of cells ungergoing active mitosis. Conclusions: Our results identify for the first time ATIP3 as a novel microtubule-associated protein whose expression is significantly reduced in highly proliferative breast carcinomas of poor clinical outcome. ATIP3 re-expression limits tumor cell proliferation in vitro and in vivo, suggesting that this protein may represent a novel useful biomarker and an interesting candidate for future targeted therapies of aggressive breast cancer.

Research paper thumbnail of Strong Correlation between Results of Fluorescent In Situ Hybridization and Immunohistochemistry for the Assessment of the ERBB2 (HER-2/neu) Gene Status in Breast Carcinoma

Modern Pathology, 2000

ERBB2 (HER-2/neu) amplification and/or overexpression are associated with poor prognosis in node-... more ERBB2 (HER-2/neu) amplification and/or overexpression are associated with poor prognosis in node-positive breast carcinoma. Its prognostic value in node-negative cases and its predictive value for response to chemotherapy remain controversial. This may be related to the use of molecular methods, which are sensitive to dilution of tumor material by normal cells, or the use of nonstandardized immunohistochemistry (IHC) procedures, for the determination of the ERBB2 gene status. In addition, new therapeutic approaches that target the cells overexpressing ERBB2 are under development. These perspectives necessitate a reliable evaluation of the status of ERBB2 in individual tumors before the application of specific therapeutic strategies. Fluorescent in situ hybridization (FISH) and IHC allow the evaluation of the ERBB2 status specifically in tumor cells on archival material. We have analyzed a series of 100 invasive ductal breast carcinomas without lymph node invasion both by IHC, using the CB11 monoclonal antibody and a sensitive Auidin Biotin Complex (ABC) immunodetection system, and by FISH, using the Oncor Inform HER-2/neu (ERBB2) gene amplification detection system as reference technique. Complete concordance between the results of FISH and IHC was seen in 98% of the cases. ERBB2 amplification (more than four signals per nucleus) was observed in 12 of the 100 cases, and all but one showed an overexpression of the protein (membrane staining) by IHC. Conversely, ERBB2 expression was present in one case without gene amplification. In conclusion, ERBB2 overexpression detected by IHC is highly correlated to gene amplification detected by FISH. Thus, under standardized conditions, IHC is a reliable and economical test to assess the ERBB2 status in tumors. The use of FISH could be limited to the verification of the status of tumors displaying a weak membrane immunostaining.

Research paper thumbnail of Secretory breast carcinomas with ETV6-NTRK3 fusion gene belong to the basal-like carcinoma spectrum

Modern Pathology, 2008

Secretory breast carcinomas (o0.15% of breast tumors) are associated with a characteristic morpho... more Secretory breast carcinomas (o0.15% of breast tumors) are associated with a characteristic morphology and a favorable prognosis. Remarkably, this entity is the only epithelial tumor of the breast with a balanced translocation, t(12;15), that creates an ETV6-NTRK3 gene fusion encoding chimeric tyrosine kinase also encountered in cellular mesoblastic nephroma and infantile fibrosarcoma. The aim of this study was to determine the phenotypic class (ie luminal A/B, ERBB2, basal-like) of secretory breast carcinoma. A series of six secretory breast carcinomas were identified in our files. The ETV6 rearrangement was confirmed in all cases by fluorescence in situ hybridization. Immunophenotype was assessed with anti-ER, PR, ERBB2, KIT, EGFR, E-cadherin, vimentin, PS100, smooth muscle actin, basal (CK5/6 and 14), luminal cytokeratins (CK8/18) and p63 antibodies. In situ and invasive components shared the same immunoprofile and were ER, PR, ERBB2 negative with expression of basal cytokeratins. ETV6 gene alterations were present in both in situ and invasive components, highlighting their genetic similarities. The immunoprofile data (triple-negative with expression of basal markers) showed that secretory breast carcinomas with ETV6-NTRK3 fusion gene belong to the phenotypic basal-like spectrum of breast carcinomas. These results support the hypothesis that secretory breast carcinomas have immunohistochemical and genetic features that distinguish them from other basal-like tumors of the breast.

Research paper thumbnail of Overexpression/Amplification of HER-2/neu is Uncommon in Invasive Carcinoma of the Uterine Cervix

International Journal of Gynecological Pathology, 2004

The aim of this study was to investigate HER-2/neu (c-erbB2) overexpression/amplification in carc... more The aim of this study was to investigate HER-2/neu (c-erbB2) overexpression/amplification in carcinoma of the uterine cervix using immunohistochemistry and fluorescent in situ hybridization (FISH) to assess whether anti-p185c-erbB2 therapy might have potential benefits in patients with advanced invasive cervical carcinoma. The authors used a protocol for p185c-erbB2 immunohistochemistry (clone CB11) that has been previously calibrated using FISH as the gold standard, showing a 98% accuracy rate in a large series of breast carcinomas. Immunolabeling for p185c-erbB2 was present in 24 of 82 (29%) of the tumors, but only 2 tumors (2%) with a labeling of more than 60% of the cells were considered positive for overexpression. FISH analysis did not find HER-2/neu gene amplification in these cases, although five other tumors showed weak and/or focal immunolabeling. There was no correlation between the presence of immunolabeling and age, histologic type, or clinical stage. Overexpression/amplification of HER-2/neu is uncommon in invasive cervical carcinoma, suggesting that there is little indication for using anti-p185c-erbB2 therapy in the treatment of these patients.

Research paper thumbnail of Oxidative stress promotes myofibroblast differentiation and tumour spreading

EMBO Molecular Medicine, 2010

JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative ... more JunD regulates genes involved in antioxidant defence. We took advantage of the chronic oxidative stress resulting from junD deletion to examine the role of reactive oxygen species (ROS) in tumour development. In a model of mammary carcinogenesis, junD inactivation increased tumour incidence and revealed an associated reactive stroma. junD-inactivation in the stroma was sufficient to shorten tumour-free survival rate and enhance metastatic spread. ROS promoted conversion of fibroblasts into highly migrating myofibroblasts through accumulation of the hypoxia-inducible factor (HIF)-1a transcription factor and the CXCL12 chemokine. Accordingly, treatment with an antioxidant reduced the levels of HIF and CXCL12 and numerous myofibroblast features. CXCL12 accumulated in the stroma of HER2-human breast adenocarcinomas. Moreover, HER2 tumours exhibited a high proportion of myofibroblasts, which was significantly correlated to nodal metastases. Interestingly, this subset of tumours exhibited a significant nuclear exclusion of JunD and revealed an associated oxido-reduction signature, further demonstrating the relevance of our findings in human cancers. Collectively, our data uncover a new mechanism by which oxidative stress increases the migratory properties of stromal fibroblasts, which in turn potentiate tumour dissemination.

Research paper thumbnail of Characterization of the Recurrent 8p11-12 Amplicon Identifies PPAPDC1B, a Phosphatase Protein, as a New Therapeutic Target in Breast Cancer

Cancer Research, 2008

The 8p11-12 chromosome region is one of the regions most frequently amplified in breast carcinoma... more The 8p11-12 chromosome region is one of the regions most frequently amplified in breast carcinoma (10–15% of cases). Several genes within this region have been identified as candidate oncogenes, as they are both amplified and overexpressed. However, very few studies have explored the role of these genes in cell transformation, with the aim of identifying valuable therapeutic targets. An analysis of comparative genomic hybridization array and expression profiling data for a series of 152 ductal breast carcinomas and 21 cell lines identified five genes (LSM1, BAG4, DDHD2, PPAPDC1B, and WHSC1L1) within the amplified region as consistently overexpressed due to an increased gene copy number. The use of small interfering RNA to knock down the expression of each of these genes showed the major role played by two genes, PPAPDC1B and WHSC1L1, in regulating the survival and transformation of two different cell lines harboring the 8p amplicon. The role of these two genes in cell survival and c...

Research paper thumbnail of High Frequency of TP53 Mutation in BRCA1 and Sporadic Basal-like Carcinomas but not in BRCA1 Luminal Breast Tumors

Cancer Research, 2009

Breast tumors with a germ-line mutation of BRCA1 (BRCA1 tumors) and basal-like carcinoma (BLC) ar... more Breast tumors with a germ-line mutation of BRCA1 (BRCA1 tumors) and basal-like carcinoma (BLC) are associated with a high rate of TP53 mutation. Because BRCA1 tumors frequently display a basal-like phenotype, this study was designed to determine whether TP53 mutations are correlated with the hereditary BRCA1 mutated status or the particular phenotype of these tumors. The TP53 gene status was first investigated in a series of 35 BRCA1 BLCs using immunohistochemistry, direct sequencing of the coding sequence, and functional analysis of separated alleles in yeast, and compared with the TP53 status in a series of 38 sporadic (nonhereditary) BLCs. Using this sensitive approach, TP53 was found to be frequently mutated in both BRCA1 (34 of 35, 97%) and sporadic (35 of 38, 92%) BLCs. However, the spectrum of mutation was different, particularly with a higher rate of complex mutations, such as insertion/deletion, in BRCA1 BLCs than in the sporadic group [14 of 33 (42%) and 13 of 34 (9%), res...

Research paper thumbnail of Identification of typical medullary breast carcinoma as a genomic sub-group of basal-like carcinomas, a heterogeneous new molecular entity

Breast Cancer Research, 2007

Introduction Typical medullary breast carcinoma (MBC) has recently been recognized to be part of ... more Introduction Typical medullary breast carcinoma (MBC) has recently been recognized to be part of the basal-like carcinoma spectrum, a feature in agreement with the high rate of TP53 mutations previously reported in MBCs. The present study was therefore designed to identify phenotypic and genetic alterations that distinguish MBCs from basal-like carcinomas (BLC). Methods Expression levels of estrogen receptor (ER), progesterone receptor (PR), ERBB2, TP53, cytokeratins (KRTs) 5/6, 14, 8/18, epidermal growth factor receptor and KIT, as well as TP53 gene sequence and high-density array comparative genomic hybridization (CGH) profiles, were assessed and compared in a series of 33 MBCs and 26 BLCs. Results All tumors were negative for ER, PR and ERBB2. KRTs 5/6 were more frequently expressed in MBCs (94%) than in BLCs (56%) (p = 0.0004). TP53 mutations were disclosed in 20/26 MBCs (77%) and 20/24 BLCs (83%). Array CGH analysis showed that a higher number of gains (95 regions) and losses (34 regions) was observed in MBCs than in BLCs (36 regions of gain; 13 regions of losses). In addition, gains of 1q and 8q, and losses of X were found to be common to the two groups, whereas gains of 10p (53% of the cases), 9p (30.8% of the cases) and 16q (25.8% of the cases), and losses of 4p (34.8% of the cases), and amplicons of 1q, 8p, 10p and 12p were the genetic alterations found to characterize MBC. Conclusion Our study has revealed that MBCs are part of the basal-like group and share common genomic alterations with BLCs, the most frequent being 1q and 8q gains and X losses; however, MBCs are a distinct entity within the basal-like spectrum, characterized by a higher rate of KRT 5/6 expression, a higher rate of gains and losses than BLCs, recurrent 10p, 9p and 16q gains, 4p losses, and 1q, 8p, 10p and 12p amplicons. Our results thus contribute to a better understanding of the heterogeneity in basal-like breast tumors and provide potential diagnostic tools. aCGH = array comparative genomic hybridization; BAC = bacterial artificial chromosome; BLC = basal-like carcinoma; ER = estrogen receptor; FISH = fluorescence in situ hybridization; KRT = cytokeratin; MBC = medullary breast carcinoma; PAC = P1-derived artificial chromosome; PR = progesterone receptor; SSC = standard saline citrate.