Long Non-Coding RNA Facilitates Cell Proliferation and Induces Apoptosis in Colorectal Cancer Via MiR-519b/ZNF277 Axis

Introduction: Long non-coding RNAs (LncRNAs) play a critical role in development and progression of various cancers. More and more researchers pay attention to the effect of lncRNA on regulating the cancer. However, the function and mechanism of in colorectal cancer have not been studied.

Methods: Reverse transcription quantitative PCR (RT-qPCR), cell counting kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU), colony formation assay, flow cytometry, TdT-mediated dUTP nick-end labeling (TUNEL), Western blot, hematoxylin-eosin staining (HE), in situ hybridization (ISH) analysis, immunohistochemistry (IHC) and tumor transplantation experiment were performed to investigate the function and mechanism of in colorectal cancer.

Results: We found that the expression level of in colorectal cancer was closely correlated with tumor size (P = 0.024), tumor depth (P = 0.035) and lymphatic invasion (P =0.067) among 50 colorectal cancer patients. Then, we proved that the expression level of was significantly increased in human colorectal cancer tissues and cell lines. Functionally, knockdown inhibited the proliferation and induced the apoptosis of colorectal cancer cells, while overexpression facilitated the proliferation and suppressed the apoptosis in colorectal cancer in vitro. Moreover, knockdown of inhibited the size and weight of tumors in mice injected with colorectal cancer cells, overexpression of promoted the growth of colorectal cancer cells in vivo. Mechanically, we found that was principally located in the cytoplasm. Furthermore, functioned as a competing endogenous RNA to induce the development and progression of colorectal cancer through sponging miR-519b-3p to upregulate ZNF277.

Discussion: Taken together, our results demonstrated that enhanced the expression level of ZEB1 to promote via competing for miR-519b-3p, which might be a promising molecular therapeutic target of colorectal cancer.