Circulating microRNA-194 and microRNA-1228 Could Predict Colon Cancer Proliferation via Phospho S6 Modulation

Although colon cancer has a decreasing incidence trend in Europe, because of its still high frequency and not fully understood pathogenesis, this malignancy still remains a subject of intense research. The aim of this study was to investigate the role of microRNA-194 and microRNA-1228 in colon cancer proliferation.

RNA was extracted from patients with colon cancer with or without advanced disease and microRNA expression levels were determined through qRT-PCR. Assays were performed on HCT116 cell line and included qRT-PCR, western blotting and cell counting.

We observed that both microRNAs 194 and 1228 were altered in patients with colon cancer compared with healthy individuals. We observed a lower expression of both microRNA-194 and microRNA-1228 in patients with advanced colon cancer. To validate their pathogenetic role we performed viability and invasion assays on HCT116 cell line transfected with mimics or inhibitors of the mentioned microRNAs, with observable changes in viability and invasion. Furthermore, to determine the altered signaling induced by these microRNAs, we performed western blotting for phospho S6 on HCT116 cells transfected with mimic and inhibitor of the above-mentioned microRNAs with observable differences.

In the current study we have shown that both microRNA-194 and microRNA-1228 alteration was correlated with the presence of advanced colon cancer, a fact that was further validated in vitro through an invasion assay. Moreover, we have also shown that their effect might be mediated through phospho S6 expression.