Expression of miRNAs from HPV-positive penile cancer patients

PeCa is a rare carcinoma in developed countries, but it presents higher incidence rates in South America, Asia, and Africa, where limited economic and social conditions play a large impact leading to delay in diagnosis, and treatment initiation. The infection by HPV is a the risk factors and can occur through the canonical HPV/p53/RB1 pathway mediated by the E2/E6/E7 viral oncoproteins. During the transformation process, HPV inserts its genetic material into host Integration Sites (IS), affecting coding genes and miRNAs. In penile cancer (PeCa) there is limited data on the miRNAs. Considering the high frequency of HPV infection in PeCa patients in Northeast Brazil, global miRNA expression profiling was performed in high-risk HPV-associated PeCa. A panel of differentially expressed miRNAs (miRDE) was successfully constructed using 22 PeCa tissues and five non-tumor penile tissues. Fresh tissues of 22 primary tumors were collected from 22 patients with squamous cell penile carcinoma who underwent surgical treatment between Jan/2014 and Dez/2016. As control, five paired non-tumors tissues was used. Total RNA from tumors and non-tumor tissues was isolated using the TRIzol protocol (Invitrogen Carlsbad, CA, USA). Expression of miRNAs was determined using the nCounter® Human v.3 miRNA expression platform (Nanostring Technologies™, Seattle, Wa, USA), which contains human probes from miRBase v.22 (http://www.mirbase.org) targeting human miRNAs, six positive controls, eight negative controls, three positive binding controls, three negative binding controls, five internal reference genes (ACTB, B2M, GAPDH, RPL19, and RPL0) and five miRNA controls (ath-miR- 159a, cel-miR-248, cel-miR-133, osa-miR-414, and osa-miR-442).