A comprehensive analysis of core polyadenylation sequences and regulation by microRNAs in a set of cancer predisposition genes

Two core polyadenylation elements (CPE) located in the 3′ untranslated region of eukaryotic pre-mRNAs play an essential role in their processing: the polyadenylation signal (PAS) AAUAAA and the cleavage site (CS), preferentially a CA dinucleotide. Herein, we characterized PAS and CS sequences in a set of cancer predisposition genes (CPGs) and performed an in silico investigation of microRNAs (miRNAs) regulation to identify potential tumor-suppressive and oncogenic miRNAs. NCBI and alternative polyadenylation databases were queried to characterize CPE sequences in 117 CPGs, including 81 and 17 known tumor suppressor genes and oncogenes, respectively. miRNA-mediated regulation analysis was performed using predicted and validated data sources. Based on NCBI analyses, we did not find an established PAS in 21 CPGs, and verified that the majority of PAS already described (74.4%) had the canonical sequence AAUAAA. Interestingly, “AA” dinucleotide was the most common CS (37.5%) associated with this set of genes. Approximately 90% of CPGs exhibited evidence of alternative polyadenylation (more than one functional PAS). Finally, the mir-192 family was significantly overrepresented as regulator of tumor suppressor genes (P