Hyperthermia increases the sensitivity of human pulmonary carcinoma PLA-801D cells to Taxotere

Objective To investigate the sensitivity of hyperthermia at different temperatures to taxotere and its mechanism. Methods Growth inhibiting rates of human pulmonary carcinoma giant cells（PLA-801D） in simple thermotherapy group,simple chemotherapy group,combined thermotherapy and chemotherapy group were determined by MTT colorimetric assay. Changes in cell cycle after treatment with hyperthermia at 42℃ and taxotere were analyzed by flow cytometry（FCM）. Results Hyperthermia at 42-43℃ suppressed the proliferation of PLA-801D cells（P＜0.01）. However,hyperthermia at 38-41℃ stimulated the proliferation of pulmonary carcinoma cells（P＜0.01）. Hyperthermia in combination with drugs could achieve best results,and the inhibitory rate was positively correlated with the change of temperature（r=0.992 0,P=0.000 1）. Cell cycle analysis showed that the amplitude of cell cycles changed greatly after combined thermotherapy and chemotherapy. Conclusion Simple hyperthermia should be applied in combination with chemotherapy. The higher the temperature of hyperthermia is,the better the effect of hyperthermia is,in the controlled range.