The aim of the present study was to investigate the effects of aloe-emodin (AE) on the radiosensitivity and differentiation of HeLa human cervical cancer cells. Cell proliferation was assessed in the HeLa cervical cancer cell line by a methylthiazolyldiphenyl-tetrazolium bromide assay. Radiosensitivity was determined by a colony‑forming assay. Flow cytometry was used for analysis of cell cycle distribution and apoptosis. The expression of γ-H2AX and cyclin B was assessed by western blotting. Alkaline phosphatase (ALP) activity was measured by an ALP activity kit. It was demonstrated that AE inhibited the proliferation of HeLa cells in a concentration- and time-dependent manner, induced G2/M and S phase cell cycle arrest and enhanced the radiosensitivity of HeLa cells. The combination of AE and radiation induced apoptosis, upregulated cyclin B and γ-H2AX expression and further improved ALP activity compared with treatment with AE or radiation alone. AE enhanced the radiosensitivity of HeLa human cervical cancer cells in vitro, inhibited the proliferation of HeLa cells, induced G2/M phase cell cycle arrest and, in combination with radiation, induced the apoptosis and improved the differentiation of HeLa cells.
Miao Jiefei,Meng Chi,Wu Hongmei,Shan Wenpei,Wang Haoran,Ling Changchun,Zhang Jinlin,Yang Tao
A novel hybrid CHC was designed and synthesized by conjugating β-carboline with an important active fragment N-hydroxyacrylamide of histone deacetylase (HDAC) inhibitor by an amide linkage to enhance antitumor efficacy/potency or even block drug resistance. CHC displayed high antiproliferative effects against drug-sensitive SUMM-7721, Bel7402, Huh7, and HCT116 cells and drug-resistant Bel7402/5FU cells with IC50 values ranging from 1.84 to 3.27 μM, which were two-to four-fold lower than those of FDA-approved HDAC inhibitor SAHA. However, CHC had relatively weak effect on non-tumor hepatic LO2 cells. Furthermore, CHC exhibited selective HDAC1/6 inhibitory effects and simultaneously augmented the acetylated histone H3/H4 and α-tubulin, which may make a great contribution to their antiproliferative effects. In addition, CHC also electrostatically interacted with CT-DNA, exerted remarkable cellular apoptosis by regulating the expression of apoptosis-related proteins and DNA damage proteins in Bel7402/5FU cells, and significantly accumulated cancer cells at the G2/M phase of the cell cycle by suppressing CDK1 and cyclin B protein with greater potency than SAHA-treated groups. Finally, CHC displayed strong inhibitory potency to drug-resistant hepatic tumors in mice. Our designed and synthetic hybrid CHC could be further developed as a significant and selective anticancer agent to potentially treat drug-resistant hepatocellular carcinoma.