André Vettore - Academia.edu (original) (raw)
Papers by André Vettore
Websites used in the selection of downregulated genes. (DOCX 12 kb)
List of ORESTES Libraries included in this study. (DOCX 12 kb)
List of accession numbers for the ORESTES data used in the study. (XLSX 20500 kb)
Downregulated genes in head and neck tumors according to the analysis of the ORESTES dataset. (DO... more Downregulated genes in head and neck tumors according to the analysis of the ORESTES dataset. (DOCX 15 kb)
Nature, Jan 13, 2000
Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically i... more Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecul...
Proceedings of the National Academy of Sciences, 2003
Chromobacterium violaceum is one of millions of species of free-living microorganisms that popula... more Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals ( i ) extensive alternative pathways for energy generation, ( ii ) ≈500 ORFs for transport-related proteins, ( iii ) complex and extensive systems for stress adaptation and motility, and ( iv ) widespread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for...
Proceedings of the National Academy of Sciences, 2003
Chromobacterium violaceum is one of millions of species of free-living microorganisms that popula... more Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals ( i ) extensive alternative pathways for energy generation, ( ii ) ≈500 ORFs for transport-related proteins, ( iii ) complex and extensive systems for stress adaptation and motility, and ( iv ) widespread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for...
TCGA sample description. (DOCX 19 kb)
Microsatellite instability (MSI) occurs in 90% of colorectal cancer (CRC) from HNPCC patients and... more Microsatellite instability (MSI) occurs in 90% of colorectal cancer (CRC) from HNPCC patients and 15% of sporadic CRC. Patients with CRC and MSI have a distinct phenotype. OBJECTIVE: this study evaluates the isolated clinicopathological significance of BAT26 instability by itself in patients with CRC. METHODS: From 1995 to 2000, 184 patients submitted to CRC surgery were selected at random. Medical records were studied in order to determine clinical data and BAT26 analysis was carried out. RESULTS: BAT26 instability was found in 22 (12%) of the 184 cases and was correlated to proximal colon tumors (p<0.001); CRC from HNPCC patients (p=0.002); poor cell differentiation (p=0,025); and mucinous component (p=0,007). BAT26 instability tumors have shown a slight trend toward absence of metastases (p=0,082). The five-year cancer-specific survival was 65% and 85% for stable and instable BAT26, respectively, with no statistical significance. CONCLUSION: BAT26 instability should be considered a useful screening method to select CRC patients for MSI.
Scientific Reports
Evaluate the biological action of valproic acid in the acetylation of histones and in the methyla... more Evaluate the biological action of valproic acid in the acetylation of histones and in the methylation of tumor suppressor genes via oral rinse in patients with a previous history of head and neck squamous cell carcinoma (HNSCC). Forty-two active or former smokers were included in this randomized, double-blind, placebo-controlled trial. Oral rinse samples were collected prior to treatment with valproic acid or placebo and after 90 days of treatment. The methylation status of five tumor suppressor genes and histone acetylation were evaluated by pyrosequencing and ELISA techniques, respectively. Differences between the 90-day and baseline oral rinse acetylation and methylation results were analyzed by comparing groups. Thirty-four patients were considered for analysis. The mean percentage adherence in the valproic and placebo groups was 93.4 and 93.0, respectively (p = 0.718). There was no statistically significant difference between groups when comparing the medians of the histone ace...
OncoTargets and Therapy
Introduction: Multiple myeloma (MM) remains an incurable disease, and patient survival requires a... more Introduction: Multiple myeloma (MM) remains an incurable disease, and patient survival requires a better understanding of this malignancy's molecular aspects. Heparanase (HPSE) is highly expressed in aggressive MM cells and related to tumor growth, metastasis, and bortezomib (BTZ) resistance. Thus, targeting HPSE seems to be a promising approach for MM treatment, and because microRNAs (miRNAs) have emerged as potential regulators of HPSE expression, the use of extracellular vesicles (EVs) can allow the efficient delivery of therapeutic miRNAs. Methods: We used prediction algorithms to identify potential miRNAs that regulate negatively HPSE expression. RT-qPCR was performed to assess miRNAs and HPSE expression in MM lines (U266 and RPMI-8226). Synthetic miRNA mimics were electroporated in MM cells to understand the miRNA contribution in HPSE expression, glycosaminoglycans (GAGs) profile, cell proliferation, and cell death induced by BTZ. EVs derived from HEK293T cells were engineered with miRNAs to evaluate their therapeutic potential combined with BTZ. Results: It revealed a direct association between BTZ sensitivity, HPSE, and miR-1252-5p expressions. Moreover, overexpression of miR-1252-5p significantly reduced HPSE expression and HPSE enzymatic activity in MM cells. The higher level of miR-1252-5p was correlated with a reduction of cell viability and higher sensitivity to BTZ. Further, EVs carrying miR-1252-5p increased MM cells' sensitivity to BTZ treatment. Conclusion: These results showed that miR-1252-5p could negatively regulate HPSE in MM, indicating the use of EVs carrying miR-1252-5p as a potential novel BTZ sensitization approach in MM cells.
Blood
Introduction: Multiple myeloma (MM) is a B-cell neoplasm characterized by multiorgan dysfunction ... more Introduction: Multiple myeloma (MM) is a B-cell neoplasm characterized by multiorgan dysfunction as a result of bone marrow infiltration by malignant cells and systemic damage of monoclonal circulating protein. Molecular studies have largely focused on acquired genetic aberrations in MM. The accumulation of genetic events is thought to be crucial for the malignant transformation of plasma cells. DNA methylation is associated with several changes in chromatin structure, including the regulation of histone methylation and acetylation and the recruitment of proteins to the methylated sites. This leads to the obstruction of the promoter, and subsequent gene silencing. Aberrant promoter methylation of genes has been described for several genes in MM. This epigenetic event acts as an alternative to mutations and deletions to disrupt tumor suppressor gene function. Objectives: We determined the aberrant DNA methylation status of 20 genes (AIM1, CCNA1, CCND2, CDH1, CDKN2A, CDKN2B, DCC, ESR1...
Journal of molecular neuroscience : MN, 2018
Glioblastoma (GBM) is an incurable disease ranked among the deadliest solid cancers worldwide. A ... more Glioblastoma (GBM) is an incurable disease ranked among the deadliest solid cancers worldwide. A better understanding on the molecular aspects of this malignancy could contribute to the development of new treatment strategies and help to improve survival rates. Previously, our group had shown that GBM patients expressing the cancer/testis antigen Opa Interacting Protein 5 (OIP5) present a longer survival period than the OIP5-negative group. The main goal of this study was to evaluate the OIP5 contribution to GBM tumorigenesis and assess the role of OIP5 in GBM cell response to lomustine, an alkylating agent used in the treatment of this malignancy. So, the effect of OIP5 knockdown was evaluated in A172 and T98G GBM cell lines. Our results demonstrated that downregulation of the OIP5 stimulates glioma cell viability and inhibits cell death-induced necrosis prompted by lomustine. In conclusion, our data shows that OIP5 expression in GBM cells seems to be able to enhance lomustine cyto...
BMC cancer, Feb 17, 2018
Aberrant methylation is a frequent event in oral cancer. In order to better characterize these al... more Aberrant methylation is a frequent event in oral cancer. In order to better characterize these alterations, a search for genes downregulated by aberrant methylation in oral squamous cell carcinoma (OSCC) was conducted through the mining of ORESTES dataset. Findings were further validated in OSCC cell lines and patients' samples and confirmed using TCGA data. Differentially expressed genes were identified in ORESTES libraries and validated in vitro using RT-PCR in HNSCC cell-lines and OSCC tumor samples. Further confirmation of these results was performed using mRNA expression and methylation data from The Cancer Genome Atlas (TCGA) data. From the set of genes selected for validation, CA3 and FHL1 were downregulated in 60% (12/20) and 75% (15/20) of OSCC samples, respectively, and in HNSCC cell lines. The treatment of cell lines JHU-13 and FaDu with the demethylating agent 5'-aza-dC was efficient in restoring CA3 and FHL1 expression. TCGA expression and methylation data on OS...
Scientific Reports, 2016
Dacomitinib, an irreversible pan-HER inhibitor, had shown modest clinical activity in squamous ce... more Dacomitinib, an irreversible pan-HER inhibitor, had shown modest clinical activity in squamous cell carcinoma of head and neck (SCCHN) patients. Therefore, validated predictive biomarkers are required to identify patients most likely to benefit from this therapeutic option. To characterize the genetic landscape of cisplatin-treated SCCHN genomes and identify potential predictive biomarkers for dacomitinib sensitivity, we performed whole exome sequencing on 18 cisplatin-resistant metastatic SCCHN tumors and their matched germline DNA. Platinum-based chemotherapy elevated the mutation rates of SCCHN compared to chemotherapy-naïve SCCHNs. Cisplatin-treated SCCHN genomes uniquely exhibited a novel mutational signature characterized by C:G to A:T transversions at CCR sequence contexts that may have arisen due to error-prone translesional synthesis. Somatic mutations in REV3L, the gene encoding the catalytic subunit of DNA polymerase ζ involved in translesional synthesis, are significantly enriched in a subset of patients who derived extended clinical benefit to dacomitinib (P = 0.04). Functional assays showed that loss-of-function of REV3L dramatically enhanced the sensitivity of SCCHN cells to dacomitinib by the loss of both translesion synthesis and homologous recombination pathways. Our data suggest that the 'platinum' mutational signature and inactivation of REV3L may inform treatment options in patients of recurrent SCCHN. Squamous cell carcinoma of the head and neck (SCCHN) is the seventh most common cancer worldwide 1. Recurrent or metastatic diseases will occur in 50-60% of patients. Although cisplatin-based chemotherapy
Journal of translational medicine, Jan 12, 2015
Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell... more Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell carcinoma (LSCC). However, up to 30% of the patients do not respond to radiotherapy. Unfortunately, we are unable to predict which tumors are likely to respond to radiation, and which will be resistant and persist. Therefore, the development of novel markers to predict response to radiotherapy is urgently needed. This study was designed to evaluate the expression pattern of microRNAs (miRNAs) in LSCC in order to identify markers capable of segregating radioresistant and radiosensitive tumors and to investigate the relationship between the expression of these miRNAs and the prognosis of LSCC. The expression profile of 667 miRNAs was determined in an initial screening of nine early-stage LSCC samples (5 radioresistant and 4 radiosensitive) using TaqMan Low-Density Array (TLDA). Real-time polymerase chain reactions were performed to validate the expression of selected miRNAs in an expanded...
Cancer Research, 2015
Background: Carcinoma of the oral tongue (OTSCC) is the most common malignancy of the oral cavity... more Background: Carcinoma of the oral tongue (OTSCC) is the most common malignancy of the oral cavity, characterized by frequent recurrence and poor survival. The last three decades has witnessed a change in the OTSCC epidemiological profile, with increasing incidence in younger patients, females and never-smokers. Here, we sought to characterize the OTSCC genomic landscape and to determine factors that may delineate the genetic basis of this disease, inform prognosis and identify targets for therapeutic intervention. Methods: Seventy-eight cases were subjected to whole-exome (n = 18) and targeted deep sequencing (n = 60).
Cancer Research, 2015
Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cause of cancer worldwide. App... more Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cause of cancer worldwide. Approximately one-third of patients present with early-stage disease and these patients are treated with either surgery or radiotherapy, with cure rates of 70-90%. The majority of patients, however, present with locally advanced stage disease. Radical treatment in this situation requires multimodality therapy with surgery, commonly followed by postoperative radiotherapy or chemotherapy. These treatments are intensive and associated with severe acute toxicity and long-term sequelae. Despite recent advances in both surgical and radiotherapy delivery techniques, up to 50% of locally advanced tumours relapse usually within the first 2 years after treatment. The development of novel therapeutic approaches and their integration into the current forms of treatment is of great interest to improve the therapeutic efficacy. Immunotherapy may provide an alternative for current treatment approach. Cancer/testis antigens (CTAs) are a family of tumor-associated antigens expressed in human tumors of different histological origin, but not in normal tissues except for testis and placenta. This tumor-restricted pattern of expression, together with their strong in vivo immunogenicity, identified CTA as ideal targets for tumor-specific immunotherapeutic approaches. A screening for CTAs expressed in HNSCC detected HORMAD1 recurrently expressed in these tumors. Objectives: The aim of this study is better understand the role of HORMAD1 in HNSCC by evaluating its influence in different tumorigenic processes, such as apoptosis, cell cycle and migration. Methods: The HORMAD1 expression was evaluated in HNSCC cell lines by RT-PCR and the presence of HORMAD1 protein was confirmed by Western Blot. HORMAD1 expression was silenced by shRNA and assays were conducted to evaluate the impact of HORMAD1 absence in cell cycle regulation and apoptosis. Results: The HORMAD1 gene was knocked-down in a HNSCC cell line and functional assays revealed a reduction in the proportion of the cells in the G1 phase of cell cycle and an induction of the apoptosis when HORMAD1 is absent. Conclusions: Our results demonstrate that HORMAD1 is frequently expressed in HNSCC and our in vitro observations indicate that this CTA may play an important role in the HNSCC carcinogenesis. Citation Format: Viviane Carlin, Dorival Mendes Rodrigues-Junior, Thais Priscila Biassi, Bruno Heidi Nakano Nozima, Marcus Vinicius Buri, Andre Luiz Vettore. HORMAD1 plays an important role in the HNSCC carcinogenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3953. doi:10.1158/1538-7445.AM2015-3953
BMC Medicine, 2015
Please note that at this stage you should only be checking for errors introduced during the produ... more Please note that at this stage you should only be checking for errors introduced during the production process. Please pay particular attention to the following when checking the proof:-Author names. Check that each author name is spelled correctly, and that names appear in the correct order of first name followed by family name. This will ensure that the names will be indexed correctly (for example if the author's name is 'Jane Patel', she will be cited as 'Patel, J.').-Affiliations. Check that all authors are cited with the correct affiliations, that the author who will receive correspondence has been identified with an asterisk (*), and that all equal contributors have been identified with a dagger sign (†).-Ensure that the main text is complete.-Check that figures, tables and their legends are included and in the correct order.-Look to see that queries that were raised during copy-editing or typesetting have been resolved.-Confirm that all web links are correct and working.-Ensure that special characters and equations are displaying correctly.-Check that additional or supplementary files can be opened and are correct. Changes in scientific content cannot be made at this stage unless the request has already been approved. This includes changes to title or authorship, new results, or corrected values.
Cancer Research, 2014
Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Functional Study of DCC Gen... more Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Functional Study of DCC Gene in Multiple Myeloma Cell Lines ABSTRACT INTRODUCTION: Multiple Myeloma (MM) is an incurable hematological malignancy characterized by multiorgan dysfunction as a result of bone marrow infiltration by malignant cells and the systemic damage of monoclonal circulating protein. Despite considerable progress in understanding MM biology, the molecular basis of this disease still remains open to debate. Previous data showed that DCC gene hypermethylation is significantly correlated with poor prognosis of MM patients. However, the involvement of DCC in the tumorigenesis process of MM remains unclear. PURPOSE: To better understand the role of DCC in this pathology through gene silencing in MM cell lines and evaluation of its interference in different tumorigenic processes. METHODS: The DCC gene expression was evaluated in three MM cell lines (RPMI-8226 and U266) and promoter methylation profile of this gene in the three cell lines was determined. The presence of DCC protein was confirmed by Western blotting (WB). The DCC expression was silenced by esiRNA and transfections were performed by electroporation. RESULTS: We detected the presence of aberrant methylation in DCC promoter in RPMI-8226, a cell line with undetectable expression of DCC. On the other hand, DCC was not methylated in U266, which present expression of DCC at mRNA and protein level. For this reason, DCC was silenced in U266 with esiRNA and its impact in the apoptosis, cell viability, proliferation and cell cycle processes was evaluated in this cell line. Support by FAPESP Citation Format: Dorival Mendes Rodrigues-Junior, Thais Priscilla Biassi, Viviane Carlin, Joel Machado-Junior, Andre Luiz Vettore. Functional Study of DCC Gene in multiple myeloma mell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2457. doi:10.1158/1538-7445.AM2014-2457
Websites used in the selection of downregulated genes. (DOCX 12 kb)
List of ORESTES Libraries included in this study. (DOCX 12 kb)
List of accession numbers for the ORESTES data used in the study. (XLSX 20500 kb)
Downregulated genes in head and neck tumors according to the analysis of the ORESTES dataset. (DO... more Downregulated genes in head and neck tumors according to the analysis of the ORESTES dataset. (DOCX 15 kb)
Nature, Jan 13, 2000
Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically i... more Xylella fastidiosa is a fastidious, xylem-limited bacterium that causes a range of economically important plant diseases. Here we report the complete genome sequence of X. fastidiosa clone 9a5c, which causes citrus variegated chlorosis--a serious disease of orange trees. The genome comprises a 52.7% GC-rich 2,679,305-base-pair (bp) circular chromosome and two plasmids of 51,158 bp and 1,285 bp. We can assign putative functions to 47% of the 2,904 predicted coding regions. Efficient metabolic functions are predicted, with sugars as the principal energy and carbon source, supporting existence in the nutrient-poor xylem sap. The mechanisms associated with pathogenicity and virulence involve toxins, antibiotics and ion sequestration systems, as well as bacterium-bacterium and bacterium-host interactions mediated by a range of proteins. Orthologues of some of these proteins have only been identified in animal and human pathogens; their presence in X. fastidiosa indicates that the molecul...
Proceedings of the National Academy of Sciences, 2003
Chromobacterium violaceum is one of millions of species of free-living microorganisms that popula... more Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals ( i ) extensive alternative pathways for energy generation, ( ii ) ≈500 ORFs for transport-related proteins, ( iii ) complex and extensive systems for stress adaptation and motility, and ( iv ) widespread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for...
Proceedings of the National Academy of Sciences, 2003
Chromobacterium violaceum is one of millions of species of free-living microorganisms that popula... more Chromobacterium violaceum is one of millions of species of free-living microorganisms that populate the soil and water in the extant areas of tropical biodiversity around the world. Its complete genome sequence reveals ( i ) extensive alternative pathways for energy generation, ( ii ) ≈500 ORFs for transport-related proteins, ( iii ) complex and extensive systems for stress adaptation and motility, and ( iv ) widespread utilization of quorum sensing for control of inducible systems, all of which underpin the versatility and adaptability of the organism. The genome also contains extensive but incomplete arrays of ORFs coding for proteins associated with mammalian pathogenicity, possibly involved in the occasional but often fatal cases of human C. violaceum infection. There is, in addition, a series of previously unknown but important enzymes and secondary metabolites including paraquat-inducible proteins, drug and heavy-metal-resistance proteins, multiple chitinases, and proteins for...
TCGA sample description. (DOCX 19 kb)
Microsatellite instability (MSI) occurs in 90% of colorectal cancer (CRC) from HNPCC patients and... more Microsatellite instability (MSI) occurs in 90% of colorectal cancer (CRC) from HNPCC patients and 15% of sporadic CRC. Patients with CRC and MSI have a distinct phenotype. OBJECTIVE: this study evaluates the isolated clinicopathological significance of BAT26 instability by itself in patients with CRC. METHODS: From 1995 to 2000, 184 patients submitted to CRC surgery were selected at random. Medical records were studied in order to determine clinical data and BAT26 analysis was carried out. RESULTS: BAT26 instability was found in 22 (12%) of the 184 cases and was correlated to proximal colon tumors (p<0.001); CRC from HNPCC patients (p=0.002); poor cell differentiation (p=0,025); and mucinous component (p=0,007). BAT26 instability tumors have shown a slight trend toward absence of metastases (p=0,082). The five-year cancer-specific survival was 65% and 85% for stable and instable BAT26, respectively, with no statistical significance. CONCLUSION: BAT26 instability should be considered a useful screening method to select CRC patients for MSI.
Scientific Reports
Evaluate the biological action of valproic acid in the acetylation of histones and in the methyla... more Evaluate the biological action of valproic acid in the acetylation of histones and in the methylation of tumor suppressor genes via oral rinse in patients with a previous history of head and neck squamous cell carcinoma (HNSCC). Forty-two active or former smokers were included in this randomized, double-blind, placebo-controlled trial. Oral rinse samples were collected prior to treatment with valproic acid or placebo and after 90 days of treatment. The methylation status of five tumor suppressor genes and histone acetylation were evaluated by pyrosequencing and ELISA techniques, respectively. Differences between the 90-day and baseline oral rinse acetylation and methylation results were analyzed by comparing groups. Thirty-four patients were considered for analysis. The mean percentage adherence in the valproic and placebo groups was 93.4 and 93.0, respectively (p = 0.718). There was no statistically significant difference between groups when comparing the medians of the histone ace...
OncoTargets and Therapy
Introduction: Multiple myeloma (MM) remains an incurable disease, and patient survival requires a... more Introduction: Multiple myeloma (MM) remains an incurable disease, and patient survival requires a better understanding of this malignancy's molecular aspects. Heparanase (HPSE) is highly expressed in aggressive MM cells and related to tumor growth, metastasis, and bortezomib (BTZ) resistance. Thus, targeting HPSE seems to be a promising approach for MM treatment, and because microRNAs (miRNAs) have emerged as potential regulators of HPSE expression, the use of extracellular vesicles (EVs) can allow the efficient delivery of therapeutic miRNAs. Methods: We used prediction algorithms to identify potential miRNAs that regulate negatively HPSE expression. RT-qPCR was performed to assess miRNAs and HPSE expression in MM lines (U266 and RPMI-8226). Synthetic miRNA mimics were electroporated in MM cells to understand the miRNA contribution in HPSE expression, glycosaminoglycans (GAGs) profile, cell proliferation, and cell death induced by BTZ. EVs derived from HEK293T cells were engineered with miRNAs to evaluate their therapeutic potential combined with BTZ. Results: It revealed a direct association between BTZ sensitivity, HPSE, and miR-1252-5p expressions. Moreover, overexpression of miR-1252-5p significantly reduced HPSE expression and HPSE enzymatic activity in MM cells. The higher level of miR-1252-5p was correlated with a reduction of cell viability and higher sensitivity to BTZ. Further, EVs carrying miR-1252-5p increased MM cells' sensitivity to BTZ treatment. Conclusion: These results showed that miR-1252-5p could negatively regulate HPSE in MM, indicating the use of EVs carrying miR-1252-5p as a potential novel BTZ sensitization approach in MM cells.
Blood
Introduction: Multiple myeloma (MM) is a B-cell neoplasm characterized by multiorgan dysfunction ... more Introduction: Multiple myeloma (MM) is a B-cell neoplasm characterized by multiorgan dysfunction as a result of bone marrow infiltration by malignant cells and systemic damage of monoclonal circulating protein. Molecular studies have largely focused on acquired genetic aberrations in MM. The accumulation of genetic events is thought to be crucial for the malignant transformation of plasma cells. DNA methylation is associated with several changes in chromatin structure, including the regulation of histone methylation and acetylation and the recruitment of proteins to the methylated sites. This leads to the obstruction of the promoter, and subsequent gene silencing. Aberrant promoter methylation of genes has been described for several genes in MM. This epigenetic event acts as an alternative to mutations and deletions to disrupt tumor suppressor gene function. Objectives: We determined the aberrant DNA methylation status of 20 genes (AIM1, CCNA1, CCND2, CDH1, CDKN2A, CDKN2B, DCC, ESR1...
Journal of molecular neuroscience : MN, 2018
Glioblastoma (GBM) is an incurable disease ranked among the deadliest solid cancers worldwide. A ... more Glioblastoma (GBM) is an incurable disease ranked among the deadliest solid cancers worldwide. A better understanding on the molecular aspects of this malignancy could contribute to the development of new treatment strategies and help to improve survival rates. Previously, our group had shown that GBM patients expressing the cancer/testis antigen Opa Interacting Protein 5 (OIP5) present a longer survival period than the OIP5-negative group. The main goal of this study was to evaluate the OIP5 contribution to GBM tumorigenesis and assess the role of OIP5 in GBM cell response to lomustine, an alkylating agent used in the treatment of this malignancy. So, the effect of OIP5 knockdown was evaluated in A172 and T98G GBM cell lines. Our results demonstrated that downregulation of the OIP5 stimulates glioma cell viability and inhibits cell death-induced necrosis prompted by lomustine. In conclusion, our data shows that OIP5 expression in GBM cells seems to be able to enhance lomustine cyto...
BMC cancer, Feb 17, 2018
Aberrant methylation is a frequent event in oral cancer. In order to better characterize these al... more Aberrant methylation is a frequent event in oral cancer. In order to better characterize these alterations, a search for genes downregulated by aberrant methylation in oral squamous cell carcinoma (OSCC) was conducted through the mining of ORESTES dataset. Findings were further validated in OSCC cell lines and patients' samples and confirmed using TCGA data. Differentially expressed genes were identified in ORESTES libraries and validated in vitro using RT-PCR in HNSCC cell-lines and OSCC tumor samples. Further confirmation of these results was performed using mRNA expression and methylation data from The Cancer Genome Atlas (TCGA) data. From the set of genes selected for validation, CA3 and FHL1 were downregulated in 60% (12/20) and 75% (15/20) of OSCC samples, respectively, and in HNSCC cell lines. The treatment of cell lines JHU-13 and FaDu with the demethylating agent 5'-aza-dC was efficient in restoring CA3 and FHL1 expression. TCGA expression and methylation data on OS...
Scientific Reports, 2016
Dacomitinib, an irreversible pan-HER inhibitor, had shown modest clinical activity in squamous ce... more Dacomitinib, an irreversible pan-HER inhibitor, had shown modest clinical activity in squamous cell carcinoma of head and neck (SCCHN) patients. Therefore, validated predictive biomarkers are required to identify patients most likely to benefit from this therapeutic option. To characterize the genetic landscape of cisplatin-treated SCCHN genomes and identify potential predictive biomarkers for dacomitinib sensitivity, we performed whole exome sequencing on 18 cisplatin-resistant metastatic SCCHN tumors and their matched germline DNA. Platinum-based chemotherapy elevated the mutation rates of SCCHN compared to chemotherapy-naïve SCCHNs. Cisplatin-treated SCCHN genomes uniquely exhibited a novel mutational signature characterized by C:G to A:T transversions at CCR sequence contexts that may have arisen due to error-prone translesional synthesis. Somatic mutations in REV3L, the gene encoding the catalytic subunit of DNA polymerase ζ involved in translesional synthesis, are significantly enriched in a subset of patients who derived extended clinical benefit to dacomitinib (P = 0.04). Functional assays showed that loss-of-function of REV3L dramatically enhanced the sensitivity of SCCHN cells to dacomitinib by the loss of both translesion synthesis and homologous recombination pathways. Our data suggest that the 'platinum' mutational signature and inactivation of REV3L may inform treatment options in patients of recurrent SCCHN. Squamous cell carcinoma of the head and neck (SCCHN) is the seventh most common cancer worldwide 1. Recurrent or metastatic diseases will occur in 50-60% of patients. Although cisplatin-based chemotherapy
Journal of translational medicine, Jan 12, 2015
Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell... more Definitive radiation therapy is the mainstay of treatment for early stage laryngeal squamous cell carcinoma (LSCC). However, up to 30% of the patients do not respond to radiotherapy. Unfortunately, we are unable to predict which tumors are likely to respond to radiation, and which will be resistant and persist. Therefore, the development of novel markers to predict response to radiotherapy is urgently needed. This study was designed to evaluate the expression pattern of microRNAs (miRNAs) in LSCC in order to identify markers capable of segregating radioresistant and radiosensitive tumors and to investigate the relationship between the expression of these miRNAs and the prognosis of LSCC. The expression profile of 667 miRNAs was determined in an initial screening of nine early-stage LSCC samples (5 radioresistant and 4 radiosensitive) using TaqMan Low-Density Array (TLDA). Real-time polymerase chain reactions were performed to validate the expression of selected miRNAs in an expanded...
Cancer Research, 2015
Background: Carcinoma of the oral tongue (OTSCC) is the most common malignancy of the oral cavity... more Background: Carcinoma of the oral tongue (OTSCC) is the most common malignancy of the oral cavity, characterized by frequent recurrence and poor survival. The last three decades has witnessed a change in the OTSCC epidemiological profile, with increasing incidence in younger patients, females and never-smokers. Here, we sought to characterize the OTSCC genomic landscape and to determine factors that may delineate the genetic basis of this disease, inform prognosis and identify targets for therapeutic intervention. Methods: Seventy-eight cases were subjected to whole-exome (n = 18) and targeted deep sequencing (n = 60).
Cancer Research, 2015
Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cause of cancer worldwide. App... more Head and neck squamous cell carcinoma (HNSCC) is the sixth leading cause of cancer worldwide. Approximately one-third of patients present with early-stage disease and these patients are treated with either surgery or radiotherapy, with cure rates of 70-90%. The majority of patients, however, present with locally advanced stage disease. Radical treatment in this situation requires multimodality therapy with surgery, commonly followed by postoperative radiotherapy or chemotherapy. These treatments are intensive and associated with severe acute toxicity and long-term sequelae. Despite recent advances in both surgical and radiotherapy delivery techniques, up to 50% of locally advanced tumours relapse usually within the first 2 years after treatment. The development of novel therapeutic approaches and their integration into the current forms of treatment is of great interest to improve the therapeutic efficacy. Immunotherapy may provide an alternative for current treatment approach. Cancer/testis antigens (CTAs) are a family of tumor-associated antigens expressed in human tumors of different histological origin, but not in normal tissues except for testis and placenta. This tumor-restricted pattern of expression, together with their strong in vivo immunogenicity, identified CTA as ideal targets for tumor-specific immunotherapeutic approaches. A screening for CTAs expressed in HNSCC detected HORMAD1 recurrently expressed in these tumors. Objectives: The aim of this study is better understand the role of HORMAD1 in HNSCC by evaluating its influence in different tumorigenic processes, such as apoptosis, cell cycle and migration. Methods: The HORMAD1 expression was evaluated in HNSCC cell lines by RT-PCR and the presence of HORMAD1 protein was confirmed by Western Blot. HORMAD1 expression was silenced by shRNA and assays were conducted to evaluate the impact of HORMAD1 absence in cell cycle regulation and apoptosis. Results: The HORMAD1 gene was knocked-down in a HNSCC cell line and functional assays revealed a reduction in the proportion of the cells in the G1 phase of cell cycle and an induction of the apoptosis when HORMAD1 is absent. Conclusions: Our results demonstrate that HORMAD1 is frequently expressed in HNSCC and our in vitro observations indicate that this CTA may play an important role in the HNSCC carcinogenesis. Citation Format: Viviane Carlin, Dorival Mendes Rodrigues-Junior, Thais Priscila Biassi, Bruno Heidi Nakano Nozima, Marcus Vinicius Buri, Andre Luiz Vettore. HORMAD1 plays an important role in the HNSCC carcinogenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3953. doi:10.1158/1538-7445.AM2015-3953
BMC Medicine, 2015
Please note that at this stage you should only be checking for errors introduced during the produ... more Please note that at this stage you should only be checking for errors introduced during the production process. Please pay particular attention to the following when checking the proof:-Author names. Check that each author name is spelled correctly, and that names appear in the correct order of first name followed by family name. This will ensure that the names will be indexed correctly (for example if the author's name is 'Jane Patel', she will be cited as 'Patel, J.').-Affiliations. Check that all authors are cited with the correct affiliations, that the author who will receive correspondence has been identified with an asterisk (*), and that all equal contributors have been identified with a dagger sign (†).-Ensure that the main text is complete.-Check that figures, tables and their legends are included and in the correct order.-Look to see that queries that were raised during copy-editing or typesetting have been resolved.-Confirm that all web links are correct and working.-Ensure that special characters and equations are displaying correctly.-Check that additional or supplementary files can be opened and are correct. Changes in scientific content cannot be made at this stage unless the request has already been approved. This includes changes to title or authorship, new results, or corrected values.
Cancer Research, 2014
Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Functional Study of DCC Gen... more Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Functional Study of DCC Gene in Multiple Myeloma Cell Lines ABSTRACT INTRODUCTION: Multiple Myeloma (MM) is an incurable hematological malignancy characterized by multiorgan dysfunction as a result of bone marrow infiltration by malignant cells and the systemic damage of monoclonal circulating protein. Despite considerable progress in understanding MM biology, the molecular basis of this disease still remains open to debate. Previous data showed that DCC gene hypermethylation is significantly correlated with poor prognosis of MM patients. However, the involvement of DCC in the tumorigenesis process of MM remains unclear. PURPOSE: To better understand the role of DCC in this pathology through gene silencing in MM cell lines and evaluation of its interference in different tumorigenic processes. METHODS: The DCC gene expression was evaluated in three MM cell lines (RPMI-8226 and U266) and promoter methylation profile of this gene in the three cell lines was determined. The presence of DCC protein was confirmed by Western blotting (WB). The DCC expression was silenced by esiRNA and transfections were performed by electroporation. RESULTS: We detected the presence of aberrant methylation in DCC promoter in RPMI-8226, a cell line with undetectable expression of DCC. On the other hand, DCC was not methylated in U266, which present expression of DCC at mRNA and protein level. For this reason, DCC was silenced in U266 with esiRNA and its impact in the apoptosis, cell viability, proliferation and cell cycle processes was evaluated in this cell line. Support by FAPESP Citation Format: Dorival Mendes Rodrigues-Junior, Thais Priscilla Biassi, Viviane Carlin, Joel Machado-Junior, Andre Luiz Vettore. Functional Study of DCC Gene in multiple myeloma mell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2457. doi:10.1158/1538-7445.AM2014-2457