[Thermotherapy enhances the sensitivity of lymphoma cell line Raji to chemotherapy in vitro].

OBJECTIVE: To observe the effect of thermotherapy on the intracellular adriamycin concentration and apoptosis of Raji cells in vitro. METHODS: The working concentration of adriamycin against Raji cells was determined with MTT assay. Raji cells were subjected to thermotherapy (at 40 degrees Celsius;, 41 degrees Celsius; or 42 degrees Celsius;) and chemotherapy with adriamycin alone or in conjunction, and the cell survival rates were determined 48 h after the treatment. The cell growth inhibition effect of the treatment was evaluated with MTT assay, and the apoptotic rates of Raji cells and alteration of intracellular adriamycin concentration were determined by flow cytometry. RESULTS: The IC(50) of adriamycin was defined as the working concentration in the experiment. Thermotherapy at 40, 41 and 42 degrees Celsius; for 60 min in conjuction with chemotherapy significantly inhibited the growth of Raji cells (P<0.01). The results of flow cytometry showed that thermotherapy and adriamycin chemotherapy, used either alone or in combination, significantly increased the apoptotic rates of Raji cells (P<0.01), and thermotherapy remarkably increased the intracellular concentration of adriamycin. CONCLUSION: Adriamycin chemotherapy combined thermotherapy for 60 min can increase the intracellular concentration of adriamycin and the apoptosis rates of Raji cells.