Functional characterization of the progestagen-associated endometrial protein gene in human melanoma (original) (raw)

Regulation of Cancer Aggressive Features in Melanoma Cells by MicroRNAs

PLoS ONE, 2011

MicroRNAs (miRNAs) are small non-coding RNAs with regulatory roles, which are involved in a broad spectrum of physiological and pathological processes, including cancer. A common strategy for identification of miRNAs involved in cell transformation is to compare malignant cells to normal cells. Here we focus on identification of miRNAs that regulate the aggressive phenotype of melanoma cells. To avoid differences due to genetic background, a comparative high-throughput miRNA profiling was performed on two isogenic human melanoma cell lines that display major differences in their net proliferation, invasion and tube formation activities. This screening revealed two major cohorts of differentially expressed miRNAs. We speculated that miRNAs up-regulated in the more-aggressive cell line contribute oncogenic features, while the down-regulated miRNAs are tumor suppressive. This assumption was further tested experimentally on five candidate tumor suppressive miRNAs (miR-31, -34a, -184, -185 and -204) and on one candidate oncogenic miRNA (miR-17-5p), all of which have never been reported before in cutaneous melanoma. Remarkably, all candidate Suppressive-miRNAs inhibited net proliferation, invasion or tube formation, while miR-17-5p enhanced cell proliferation. miR-34a and miR-185 were further shown to inhibit the growth of melanoma xenografts when implanted in SCID-NOD mice. Finally, all six candidate miRNAs were detected in 15 different metastatic melanoma specimens, attesting for the physiological relevance of our findings. Collectively, these findings may prove instrumental for understanding mechanisms of disease and for development of novel therapeutic and staging technologies for melanoma.

Signatures of MicroRNAs and Selected MicroRNA Target Genes in Human Melanoma

Cancer Research, 2010

Small noncoding microRNAs (miRNA) regulate the expression of target mRNAs by repressing their translation or orchestrating their sequence-specific degradation. In this study, we investigated miRNA and miRNA target gene expression patterns in melanoma to identify candidate biomarkers for early and progressive disease. Because data presently available on miRNA expression in melanoma are inconsistent thus far, we applied several different miRNA detection and profiling techniques on a panel of 10 cell lines and 20 patient samples representing nevi and primary or metastatic melanoma. Expression of selected miRNAs was inconsistent when comparing cell line-derived and patient-derived data. Moreover, as expected, some discrepancies were also detected when miRNA microarray data were correlated with qPCR-measured expression levels. Nevertheless, we identified miRNA-200c to be consistently downregulated in melanocytes, melanoma cell lines, and patient samples, whereas miRNA-205 and miRNA-23b were markedly reduced only in patient samples. In contrast, miR-146a and miR-155 were upregulated in all analyzed patients but none of the cell lines. Whole-genome microarrays were performed for analysis of selected melanoma cell lines to identify potential transcriptionally regulated miRNA target genes. Using Ingenuity pathway analysis, we identified a deregulated gene network centered around microphthalmia-associated transcription factor, a transcription factor known to play a key role in melanoma development. Our findings define miRNAs and miRNA target genes that offer candidate biomarkers in human melanoma. Cancer Res; 70(10); 4163-73.

Micro RNAs Promoting Growth and Metastasis in Preclinical In Vivo Models of Subcutaneous Melanoma

Cancer Genomics & Proteomics, 2020

During the last years a considerable therapeutic progress in melanoma patients with the RAF V600E mutation via RAF/MEK pathway inhibition and immuno-therapeutic modalities has been witnessed. However, the majority of patients relapse after therapy. Therefore, a deeper understanding of the pathways driving oncogenicity and metastasis of melanoma is of paramount importance. In this review, we summarize microRNAs modulating tumor growth, metastasis, or both, in preclinical melanoma-related in vivo models and possible clinical impact in melanoma patients as modalities and targets for treatment of melanoma. We have identified miR-199a (ApoE, DNAJ4), miR-7-5p (RelA), miR-98a (IL6), miR-219-5p (BCL2) and miR-365 (NRP1) as possible targets to be scrutinized in further target validation studies.

Melanoma Development: Current Knowledge on Melanoma Pathogenesis

Acta dermatovenerologica Croatica : ADC, 2019

The pathogenic features of melanomas include growth and amplification of atypical melanocytes associated with several features (self-sufficiency of growth factors, insensitivity to growth inhibitors, evasion of cellular apoptosis, limitless replicative potential, sustained angiogenesis, tissue invasion, and metastasis). These melanoma pathogenic events can be triggered by activating oncogenes or inactivating tumor-suppressor genes by means of molecular mechanisms such as dotted mutations, deletions, and translocations or epigenetic mechanisms such as microRNA expression and promoter methylation. In melanomas, an analysis of the gene aberrations in the genome has led to the discovery of the complex interaction of signaling pathways. Progression of melanomas also involves genetic instability and selective growth of cells with favorable mutations. Additional factors include genetic predisposition, mutagenesis, and suppressed host immune response. Some of the most important signaling pa...

Analysis of candidate genes expected to be essential for melanoma surviving

Cancer Cell International

Introduction Cancers may be treated by selective targeting of the genes vital for their survival. A number of attempts have led to discovery of several genes essential for surviving of tumor cells of different types. In this work, we tried to analyze genes that were previously predicted to be essential for melanoma surviving. Here we present the results of transient siRNA-mediated knockdown of the four of such genes, namely, UNC45A, STK11IP, RHPN2 and ZNFX1, in melanoma cell line A375, then assayed the cells for their viability, proliferation and ability to migrate in vitro. In our study, the knockdown of the genes predicted as essential for melanoma survival does not lead to statistically significant changes in cell viability. On the other hand, for each of the studied genes, mobility assays showed that the knockdown of each of the target genes accelerates the speed of cells migrating. Possible explanation for such counterintuitive results may include insufficiency of the predictin...

microRNA-378a-5p iS a novel positive regulator of melanoma progression

Oncogenesis, 2020

Evaluating the expression levels of miR-378a-5p both in a large melanoma patient cohort from The Cancer Genome Atlas database and in melanoma patients from our Institute, we found that miR-378a-5p is upregulated in metastatic melanoma specimens. miR-378a-5p expression was also increased in melanoma cells resistant to target therapy, and decreased in response to drug treatment. We also demonstrated that overexpression of miR-378a-5p enhances in vitro cell invasion and migration, and facilitates the ability of melanoma cells to form de novo vasculogenic structures. While performing downstream targeting studies, we confirmed the ability of miR-378a-5p to modulate the expression of known target genes, such as SUFU, FUS-1, and KLF9. Luciferase-3′UTR experiments also identified STAMBP and HOXD10 as new miR-378a-5p target genes. MMP2 and uPAR, two HOXD10 target genes, were positively regulated by miR-378a-5p. Genetic and pharmacologic approaches inhibiting uPAR expression and activity evid...

Comparative Expression Profiling Reveals Molecular Markers Involved in the Progression of Cutaneous Melanoma towards Metastasis

International Journal of Molecular Sciences

Cutaneous melanoma is one of the most aggressive types of cancer and often proves fatal in metastatic stages. Few treatment options are available, and its global incidence is quickly increasing. In order to gain an improved understanding of the molecular features regarding melanoma progression, we have compared gene and small non-coding RNA expression profiles from cell lines derived from primary melanoma (MelJuSo), lymph node metastasis (MNT-1) and brain metastasis (VMM1), representing distinct stages of malignant progression. Our preliminary results highlighted the aberrant regulation of molecular markers involved in several processes that aid melanoma progression and metastasis development, including extracellular matrix remodeling, migratory potential and angiogenesis. Moreover, bioinformatic analysis revealed potential targets of the microRNAs of interest. Confocal microscopy and immunohistochemistry analysis were used for validation at the protein level. Exploring the molecula...

Inhibiting the growth of malignant melanoma by blocking the expression of vascular endothelial growth factor using an RNA interference approach

British Journal of Dermatology, 2005

Background Vascular endothelial growth factor (VEGF) is overexpressed in malignant melanoma (MM). Objectives To develop an RNA interference approach that specifically targets VEGF by constructing a eukaryotic expression plasmid containing short interfering RNA (siRNA), and to evaluate the effects of this vector on the proliferation and apoptosis of MM in vitro and in vivo. Methods pU-VEGF-siRNA plasmid was transfected into MM cell line A375 and colorectal carcinoma cell line Lovo by electroporation. Expression of VEGF mRNA and protein in A375 and Lovo cells after gene transfer was detected by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Proliferation of pU-VEGF-siRNA-transfected A375 and Lovo cells and control cells was observed by cell counting through the microscope. The proliferation of human umbilical vein endothelial cells (ECV-304) cultured in medium containing supernatants of transfected and control A375 cells was measured by the cell counting method. Flow cytometry (FCM) was used to analyse the apoptosis of transfected and control groups. In a mouse model, tumorigenicity and tumour growth of transfected cells were studied in vivo. VEGF expression and microvessel density (MVD) in tumour tissue were measured by immunohistochemistry. Apoptosis in tumours was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling. Results Expression of VEGF mRNA and protein in pU-VEGF-siRNA-transfected A375 and Lovo cells was significantly decreased on days 3, 10, 17 and 24 post-transfection, compared with controls. The greatest suppression occurred on days 3 and 10 post-transfection. The proliferation of transfected A375 cells and ECV-304 cocultured with supernatants of transfected A375 cells was inhibited. FCM analysis showed that a hypodiploidy peak was found only in A375 cells transfected by pU-VEGF-siRNA. After subcutaneous inoculation with pU-VEGF-siRNA-transfected A375 cells, tumour growth in mice was inhibited, VEGF expression and MVD were decreased, and tumour apoptosis was increased significantly, in comparison with mice inoculated with untransfected A375 cells. Conclusions The delivery of siRNA directed against VEGF was shown not only to give efficient and specific downregulation of the expression of VEGF, inhibit proliferation of A375 and ECV-304 cells and induce apoptosis of A375 cells in vitro, but also to suppress growth of MM in vivo. These results suggest that a strategy based on siRNA targeting of VEGF may build the foundation to the clinical management of MM.

Melanoma and Associated MicroRNAs

Journal of Skin and Stem Cell, 2016

Context: Melanoma is an invasive type of skin cancer, with a rapidly increasing incidence. Therefore, new approaches are required to treat this aggressive cancer. MicroRNAs (miRNAs) are introduced as novel components in melanoma. This review study aimed to determine the relationship between melanoma and miRNAs. Evidence Acquisition: Prognostic, diagnostic, and therapeutic applications of miRNAs in skin cancer have been recently investigated from different aspects. Some of these studies on miRNAs were reviewed, and the mechanisms of some genetic modifications were determined in this study. Results: Since recommendations for miRNAs have increased in the past decades, and scientists have confirmed their great efficacy in multiple aspects of cancer treatment, different strategies have been developed considering their therapeutic effects. Therefore, further studies are required to confirm miRNA application in melanoma treatment. Conclusions: This review study included various investigations concerning miRNA traces as molecular rearrangements in melanoma. It was revealed that multiple miRNAs are efficient in molecular signaling and can be used as prognostic, diagnostic, and therapeutic biomarkers. Although the exact relationship between aberrant expression of miRNAs and cancers has been confirmed, further studies are required to introduce more thorough and accurate applications of miRNAs in melanoma.

Promoter-Associated RNAs Regulate HSPC152 Gene Expression in Malignant Melanoma

Non-Coding RNA, 2016

The threshold of 200 nucleotides (nt) conventionally divides non-coding RNAs (ncRNA) into long ncRNA (lincRNA, that have more than 200 nt in length) and the remaining ones which are grouped as "small" RNAs (microRNAs, small nucleolar RNAs and piwiRNAs). Promoter-associated RNAs (paRNAs) are generally 200-500 nt long and are transcribed from sequences positioned in the promoter regions of genes. Growing evidence suggests that paRNAs play a crucial role in controlling gene transcription. Here, we used deep sequencing to identify paRNA sequences that show altered expression in a melanoma cell line compared to normal melanocytes. Thousands of reads were mapped to transcription start site (TSS) regions. We limited our search to paRNAs adjacent to genes with an expression that differed between melanoma and normal melanocytes and a length of 200-500 nt that did not overlap the gene mRNA by more than 300 nt, ultimately leaving us with 11 such transcripts. Using quantitative real-time PCR (qRT-PCR), we found a significant correlation between the expression of the mRNA and its corresponding paRNA for two studied genes: TYR and HSPC152. Ectopic overexpression of the paRNA of HSPC152 (designated paHSPC) enhanced the expression of the HSPC152 mRNA, and an siRNA targeting the paHSPC152 decreased the expression of the HSPC152 mRNA. Overexpression of paHSPC also affected the epigenetic structure of its putative promoter region along with effects on several biologic features of melanoma cells. The ectopic expression of the paRNA to TYR did not have any effect. Overall, our work indicates that paRNAs may serve as an additional layer in the regulation of gene expression in melanoma, thus meriting further investigation.