OBJECTIVETo study the effect of hyperthermia on anti-invasion of Tca8113 and the expression change of matrix metalloproteinase-13 (MMP-13) and calcium-binding protein S100A4 (S100A4).

METHODSTca8113 cell pools were incubated at 43 degrees C for 0, 40, 80, 120 min, respectively, and at 37, 41, 43, 45 degrees C respectively for 80 min. The effect of high temperatures on the invasion ability of Tca8113 was measured in vitro. The slides of cells were made and incubated at 43 degrees C for 0, 40, 80, 120 min, respectively. Immunocytochemical method was employed for detecting the expression change of MMP-13 and S100A4 protein. Tca8113 cells were incubated at 43 degrees C for 0, 40, 80, 120 min respectively and at 37, 41, 43, 45 degrees C respectively for 80 min. Western blot method was conducted for detecting the expressionchange of MMP-13 and S100A4 protein.

RESULTSAs incubating time at higher temperature lasted, the proportion of the cells with invasion ability decreased. Except groups of 40 min and 80 min at 43 degrees C and 41, 43 degrees C for 80 min, the rest groups show significant statistic differences (P < 0.05). The expression intensity of MMP-13 and S100A4 proteins in Tca8113 cells would decrease as incubating time at higher temperature lasted. The content of MMP-13 and S100A4 proteins would decrease as incubating time at higher temperature lasted or incubating temperature increased. Except the groups of 40, 80 min at 43 degrees C and 41, 43 degrees C for 80 min, statistic differences were identified (P < 0.05).

CONCLUSIONThe invasion of Tca8113 could be inhibited by hyperthermia. The mechanism of this effect may be due to protein expression inhibition of MMP-13 and S100A4.