ALTERAÇÕES GENÔMICAS GLOBAIS E EXPRESSÃO DIFERENCIAL DE MICRORNAS EM CARCINOMA PENIANO: VIAS MOLECULARES AFETADAS E POTENCIAIS ALVOS TERAPÊUTICOS

Abstract

Penile cancer (PeCa) is a rare neoplasm in developed countries. However, its incidence is higher in developing ones, such as Brazil, particularly in the Northeast region, which is characterized by low socioeconomic levels and a high prevalence of human papillomavirus infection (HPV). Genetic and epigenetic alterations have been studied in several tumors, however the role of microRNAs (miRNAs) on the establishment and progression of PeCa is still unclear, especially for those associated with HPV. In this study we focused on two approaches: 1) we used array-CGH to identify miRNAs located at cytobands with copy number alterations (CNAs). Further, bioinformatics analysis were used to identify potential cellular pathways and therapeutic targets; 2) we identified differentially expressed miRNAs (miRDE) in the tumors using nCounter® Human v.3 miRNA Expression platform (Nanostring Technologies™, Seattle, WA, USA). After that, we assessed the effect of miRNAs on gene interaction networks and druggable targets using the DIANA-tools, STarMir, KEGG (Kyoto Encyclopedia of Genes and Genomes), Pharmaco-miR, and DGIdb (Drug Gene Interaction Database) platforms. The aCGH analysis identified 269 miRNAs and 2,395 genes that were mapped to regions containing CNAs, 92.6% and 96.7% of which were at HPV integration sites (HPVis), respectively. Pathway’s enrichment revealed five major signaling pathways (hippo signaling, lysine degradation, O-glycan mucin biosynthesis, prions and proteoglycans in cancer), as well as the carcinogenesis pathway associated with HPV infection. The global expression panel revealed 507 miRDE compared to non-tumor penile tissues, of which 92% of the most overexpressed and underexpressed (n=25) are found in HPVis. Pharmaco-miR and DGIdb pharmacogenomic prediction analysis of those miRNAs identified EGFR, COX2, MDM2 and MDM4 as potential therapeutic targets. We also performed the STarMir target prediction analysis, whereby we found that all 13 overexpressed miRNAs downregulate TP53 and RB1, primarily through non-canonical “seedless” regions. Furthermore, we describe miR-1206, miR-376b-3p and miR-495- 3p associated with perineural invasion, and we highlight miR-376a-2-5p as possible prognostic marker. In conclusion, our findings indicate that HPV is associated with deregulation of CNAs and miRNAs, disrupting signaling pathways involved in the establishment and progression of HPV-mediated penile tumors, opening perspectives for new potential targets for the treatment of patients.