Small non-coding RNA deregulation in endometrial carcinogenesis.

Small non-coding RNAs (sncRNAs) represent a heterogeneous group of <200nt-long transcripts comprising microRNAs, PIWI-interacting RNAs (piRNAs) and small-nucleolar-RNAs (snoRNAs) involved in physiological and pathological processes such as carcinogenesis and tumor progression. Aberrant sncRNA expression in cancer has been associated with specific clinical phenotypes, grading, staging, metastases development and resistance to therapy.Aim of the present work is to study the role of sncRNAs in endometrial carcinogenesis. Changes in sncRNA expression were identified by high-throughput genomic analysis of paired normal, hyperplastic and cancerous endometrial tissues obtained by endometrial biopsies (n = 10). Using smallRNA sequencing and microarrays we identified significant differences in sncRNA expression pattern between normal, hyperplastic and neoplastic endometrium. This led to the definition of a sncRNA signature (129 microRNAs, 2 of which not previously described, 10 piRNAs and 3 snoRNAs) of neoplastic transformation. Functional bioinformatics analysis identified as downstream targets multiple signaling pathways potentially involved in the hyperplastic and neoplastic tissue responses, including Wnt/β-catenin, and ERK/MAPK and TGF-β-Signaling.Considering the regulatory role of sncRNAs, this newly identified sncRNA signature is likely to reflect the events leading to endometrial cancer, which can be exploited to dissect the carcinogenic process including novel biomarkers for early and non-invasive diagnosis of these tumors.