A novel benzothiazole derivative SKLB826 inhibits human hepatocellular carcinoma growth via inducing G2/M phase arrest and apoptosis

Abstract

Hepatocellular carcinoma is the fifth most common cancer and durable responses in conventional treatments are limited so researchers have been devoted to developing new anti-HCC agents. Benzothiazole derivatives are known for various biological activities and have received considerable attention in cancer therapy, hence we designed and synthesized a novel potent benzothiazole compound 2-chloro-N-(2-(2-(2-morpholino-2-oxoethyl)thio)-2,3-dihydrobenzo[d]thiazol-6-yl)acetamide (SKLB826) and further investigated the biological activities against cancer. The results suggested that SKLB826 showed growth inhibition against a broad spectrum of human cancer cells, especially human HCC cell lines, in a dose-dependent manner and induced G2/M phase arrest via down-regulating the CDK1, cyclinA2 and cdc25c protein levels. SKLB826 could also induce apoptosis of HCC cells via decreasing the expression of Bcl-2 and increasing the levels of BAX and cleaved caspase-3, 9. Moreover, after treatment with SKLB826, the change of ROS level and ΔΨ_m suggested that SKLB826 might induce apoptosis through an intrinsic mitochondrial apoptotic pathway. Furthermore, SKLB826 could suppress tumor growth in the HepG2 xenograft model without inducing any notable major organ-related toxicity, suggesting that SKLB826 may be a potential candidate for HCC therapy.