The Bioinformatics Study of the Interactions between MicroRNAs and Genes Involved in Relapse of breast Cancer Treated with Tamoxifen

Background and Objective: Tamoxifen is the most commonly used treatment for the patients with breast cancer called ER +, which prevents the expression of genes that are effective in the growth and proliferation of cancer cells by estrogen. Resistant to Tamoxifen is a major clinical problem in breast cancer treatment. In recent studies, the role of microRNAs in tamoxifen resistance has been raised through the influence of regulation of cell cycle control genes. Throughout this study, the interactions of microRNAs with genes involved in tamoxifen resistance were investigated. Materials and Methods: By comparing the gene expression data in samples of patients sensitive and resistant to Tamoxifen from the GEO database and searching in the database of articles, genes and microRNAs with significant expression variations were determined. Then, by examining the correlation between the expression of genes and microRNAs and bioinformatics by mirwalk software, the interconnection network between the genes and microRNAs was drawn. Results: The results showed that 21 genes and 62 microRNAs altered in Tamoxifen resistant specimens. With miR342-3P/5P targeting the HOXB13, PRM2, and KLK3 genes, and MiR-520h and miR-582-5p microRNAs, targeting 5 reduced expression genes, can lead to recurrence of breast cancer. Conclusion: The regulatory network mapped out between a set of genes and microRNAs that are potentially involved in the recurrence of breast cancer treated with Tamoxifen could clarify the role of the microRNAs in the recurrence of breast cancer.