Y H Huang1, Y S Zhen. 1. Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences, Pekin Union Medical College, Beijing 100050, China.
Abstract
AIM: To study the apoptosis-inducing and growth-inhibitory effect of rhein, an herb-derived compound, and its combination with mitomycin C (MMC) on cultured tumor cells. METHODS: MTT assays were used to determine the inhibition of proliferation by drugs in several tumor cell lines. Nucleoside transport and DNA synthesis inhibition were determined by [3H] thymidine transport and incorporation assays. Flow cytometry, electrophoresis on agarose gels and morphological assessment were applied to analyze the apoptotic changes. RESULTS: The IC50 values of nucleoside transport was 19.1 micrograms.mL-1 and that of the DNA synthesis inhibited by rhein was 27.4 micrograms.mL-1. In MTT assay the IC50 values of rhein for KB, hepatoma BEL-7402 and mammary carcinoma MCF-7 cells were 11.5 micrograms.mL-1, 14.0 micrograms.mL-1 and 18.4 micrograms.mL-1 respectively. Synergistic effect of rhein and MMC was found in all the three cell lines. As found, rhein induced apoptosis in KB cells, and the increase of apoptotic cells reached 71.0% at 96 h. The combination of rhein and MMC enhanced the induction of apoptosis significantly. CONCLUSION: These results suggest that rhein, as a biochemical modulator, might be potentially useful in cancer chemotherapy.
AIM: To study the apoptosis-inducing and growth-inhibitory effect of rhein, an herb-derived compound, and its combination with mitomycin C (MMC) on cultured tumor cells. METHODS:MTT assays were used to determine the inhibition of proliferation by drugs in several tumor cell lines. Nucleoside transport and DNA synthesis inhibition were determined by [3H] thymidine transport and incorporation assays. Flow cytometry, electrophoresis on agarose gels and morphological assessment were applied to analyze the apoptotic changes. RESULTS: The IC50 values of nucleoside transport was 19.1 micrograms.mL-1 and that of the DNA synthesis inhibited by rhein was 27.4 micrograms.mL-1. In MTT assay the IC50 values of rhein for KB, hepatoma BEL-7402 and mammary carcinoma MCF-7 cells were 11.5 micrograms.mL-1, 14.0 micrograms.mL-1 and 18.4 micrograms.mL-1 respectively. Synergistic effect of rhein and MMC was found in all the three cell lines. As found, rhein induced apoptosis in KB cells, and the increase of apoptotic cells reached 71.0% at 96 h. The combination of rhein and MMC enhanced the induction of apoptosis significantly. CONCLUSION: These results suggest that rhein, as a biochemical modulator, might be potentially useful in cancer chemotherapy.