Experimental Studies On Paclitaxel-mediated Apoptosis In Osteosarcoma Cell Line

Objective To study the growth inhibitory and apoptosis-inducting effect of paclitaxel on human osteoblastic cell line U-2 OS.Methods U-2 OS cells were treated with paclitaxel and other chemotherapeutic drug. The cytotoxic effect depended on time and dose were examined by cell count, morphologic observation under light and transmission electron microscopes, flow cytometry assays and immunohistochemical detection (TdT-mediated dUTP nick end labeling technique, TUNEL).Results Paclitaxel has a growth inhibitory and apoptosis-inducting effect on U-2 OS cell. The cell treated with paclitaxel initially shows G2/M arrest; follow by apoptosis. A Characteristic apoptosis change including nuclear disintegration and chromatin agglomerate were displayed. Lots of multinucleate cells appeared, which was not seen on the cell treated with other chemotherapftutic agents such as cisplatin and adriamycin. Also, extensive DNA-cleavage was detected by immunohistochemical technique.Conclusion Paclitaxel has an obvious growth inhibitory and apoptosis-inducting effect on osteosarcoma cell line by induce a G2/M arrest and inhibit the mitosis. The effect of paclitaxel displays a time-dependent and dose- dependent manner.