Abstract: Colorectal neoplasia differentially expressed (CRNDE ) is a novel gene recognized as a long noncoding RNA (lncRNA) that is highly elevated in colorectal cancer and many other solid tumors but its functions on metastasis and oxaliplatin (OXA) resistance are unknown. In our study, we confirmed the upregulation of CRNDE  in both primary specimens from colorectal cancer patients and colorectal cancer cell lines. Knockdown of CRNDE  expression inhibited the migration and invasion potency of colorectal cancer cells with no effect on cell apoptosis. Overexpression of CRNDE  promoted the migration and invasion potency of colorectal cancer cells. Furthermore, we found that CRNDE  conferred chemoresistance in colorectal cancer cells. Knockdown of CRNDE  with OXA treatment decreased cell viability and promoted DNA damage and cell apoptosis, while the overexpression of CRNDE  with OXA treatment reduced DNA damage and cell apoptosis. Further in-depth mechanistic studies revealed that CRNDE  functioned as a competing endogenous RNA for miR-136, led to the de-repression of its endogenous target, E2F transcription factor 1 (E2F1). Overall, our findings demonstrate that CRNDE  functions as a competing endogenous RNA to promote metastasis and OXA resistance by sponging miR-136 in colorectal cancer.
Keywords: CRNDE , colorectal cancer, metastasis, oxaliplatin resistance, miR-136, E2F1