Knockdown of CUL4B inhibits proliferation and promotes apoptosis of colorectal cancer cells through suppressing the Wnt/β-catenin signaling pathway.

Colorectal cancer is one of the leading causes of cancer related deaths worldwide. Cullin 4B (CUL4B) is over-expressed in diverse cancer types. However, the function and precise molecular mechanism of CUL4B in colorectal cancer remains largely unknown. Therefore, in this study, we examined the expression of CUL4B in colorectal cancer cell lines and its effects on cellular proliferation and apoptosis, and the underlying mechanism was also explored. Our results showed that CUL4B was significantly overexpressed in colorectal cancer cell lines. Silencing CUL4B obviously inhibited proliferation and tumorigenicity of colorectal cancer cells both in vitro and in vivo, and it also promoted the apoptosis of colorectal cancer cells. Moreover, knockdown of CUL4B inhibited the expression of β-catenin, cyclin D1 and c-Myc in colorectal cancer cells. Taken together, these results showed that knockdown of CUL4B inhibit proliferation and promotes apoptosis of colorectal cancer cells through suppressing the Wnt/β-catenin signaling pathway. Therefore, CUL4B may represent a novel therapeutic target for colorectal cancer treatment.