Targeting LncRNA EPIC1 to inhibit human colon cancer cell progression

Long non-coding RNA EPIC1 (Lnc-EPIC1) binds MYC protein, which is essential for MYC function and expression of MYC target genes. The current study tested its expression and potential functions in human colon cancer cells. We show that Lnc-EPIC1 expression is elevated in human colon cancer tissues and primary human colon cancer cells. Whereas its expression is relatively low in normal colon tissues and colon epithelial cells. In the primary human colon cancer cells, Lnc-EPIC1 siRNA largely inhibited cancer cell growth, proliferation, migration and invasion. Further, Lnc-EPIC1 silencing induced significant apoptosis activation in colon cancer cells. Conversely, ectopic overexpression of Lnc-EPIC1 augmented colon cancer cell growth, proliferation, migration and invasion. RNA-immunoprecipitation and RNA pull-down results confirmed that Lnc-EPIC1 directly binds MYC protein in colon cancer cells. MYC target proteins, including cyclin A, cyclin D and CDK9, were downregulated with Lnc-EPIC1 silencing, but upregulated after Lnc-EPIC1 overexpression in colon cancer cells. Further Lnc-EPIC1 silencing or overexpression failed to alter functions of MYC-knockout colon cancer cells. Collectively, overexpressed Lnc-EPIC1 is important for the progression of human colon cancer cells.