Potential role of ZEB1 as a DNA repair regulator in colorectal cancer cells revealed by cancer-associated promoter profiling.

Besides being a key contributor to epithelial‑to‑mesenchymal transition (EMT) activation and stemness maintenance, zinc finger E-box binding homeobox 1 (ZEB1) is also a crucial inducer of chemoresistance and radioresistance. Unlike the clear mechanism that mediates its effect on EMT and dedifferentiation, the mechanism of how ZEB1 promotes chemo- and radio-resistance remains to be elucidated. It has been previously reported that ZEB1 promotes DNA double-strand break clearance by enhancing the deubiquitylating activity of ubiquitin-specific peptidase (USP)7 on checkpoint kinase 1, which is an important step during DNA repair.

Xihuang Pill () induces mesenchymal-epithelial transition and inhibits loss of apical-basal polarity in colorectal cancer cell through regulating ZEB1-SCRIB loop.

Objective: To investigate the antiproliferative and anti-metastasis effect of Xihuang Pill (, XP) on human colorectal cancer cell and to explore the molecular mechanism by which it produces the effects.

Methods: Highly metastatic human colorectal cancer cell line LoVo was treated with low-, medium-, and highdose XP-containing serum (XP-L, XP-M, XP-H) groups for 48 h, cells intervened with no drug rat serum and PD98059 [extracellular signal-regulated kinase (ERK) inhibitor] as negative and positive controls (NC and PC) groups. Cell proliferation assay was made using cell counting kit-8 (CCK8).