Fluorescence microscopic and microautoradiographic studies on apoptosis of bone tumor cells induced by 153Sm-EDTMP

The apoptosis of bone tumor cells treated with internal irradiation by 153Sm-EDTMP was studied. The morphological changes in bone tumor cells were observed by fluorescence microscopic and microautoradiographic observations. It was found that bone tumor cells internally irradiated with 153Sm-EDTMP, displayed significant nuclear fragmentation and marked pyknosis as well as apoptotic bodies formation. The microautoradiographic study showed that 153Sm-EDTMP could permeate through cell membrane and displayed membrane-seeking condensation in tumor cells. Soon afterwards 153Sm-EDTMP could be phagocytized by the tumor cells and distributed in cytoplasm and nucleus in the form of phagosome. With the prolongation of observing time, the membrane-bounded apoptotic bodies was observed. With the lengthening of internal irradiation time by 153Sm-EDTMP, the inhibition rate of proliferation of bone tumor cells increased progressively. (10 refs., 9 figs., 1 tab.)