Zaozao Wang

Department of Minimally Invasive Gastrointestinal Surgery, Peking University Cancer Hospital & Institute

Objective:Loss of DCP4 plays a key role in the development of colorectal cancer. Recent studies demonstrated that ectopically expressed miRNAs is another important factor which lead to DCP4 inactivation. With the emerging concern of "RNA crosstalk”, competitive endogenous RNA (ceRNA) has been attracting more attention. By competing for the same pool of miRNAs with the target mRNA, ceRNA could regulate target gene expression through miRNAs. In this study, we have identified VAMP24 as the ceRNA of DCP4 in colorectal cancer. Method: The candidate ceRNAs of DCP4 was identified through bioinformatic tools, and the expression correlation between ceRNAs and DCP4 was analyzed by GEO database. The miRNA-dependent regulation of DCP4 by VAMP24 was evaluated in colorectal cancer cell line and specimens. Result: We have identified10 putative ceRNAs of DCP4 through bioinformatic tools. After expression correlation between candidate ceRNAs and DCP4 evaluated in GEO dataset, we find the expression of VAMP24 was positively correlated with DCP4, and they share 10identical miRNAs. Knockdown of VAMP24 could down-regulate DCP4 in both protein and mRNA level. Further, the expression of DCP4 and VAMP24 was closely correlated in colorectal srecimens. Conclusion: Taken together, our study has clarified the epigenetic regulation of DCP4 by VAMP24, and provide some new clues for the prevention and treatment of colorectal cancer.

Key Words: colorectal cancer  ceRNA  DCP4