There is increasing evidence suggesting that S100P has a significant role in cancer, and is associated with poor clinical outcomes. The expression of S100P mRNA and protein in endometrial cancer and normal endometrium tissues was detected by real-time quantitative RT-PCR and immunohistochemistry. Moreover, we reduced the expression of S100P in HEC-1A and Ishikawa endometrial cancer cell lines by siRNA transfection. Based on the reduced S100P mRNA expression, we measured the effects of S100P on cellular proliferation by the cell-counting kit-8. Nuclear β-catenin protein level was detected by western blotting. Cyclin D1 and c-myc mRNA expression regulated by β-catenin was detected by real-time quantitative RT-PCR. We found that the expression of S100P mRNA and protein increased in endometrial cancer tissues compared with the normal endometrium. Local S100P expression progressively increased from pathologic differenciation grade 1 to 3. After reducing the S100P expression, the cellular proliferation ability, nuclear β-catenin protein level, cyclin D1 and c-myc mRNA levels reduced. It indicated that S100P could promote cell proliferation by increasing nuclear translocation of β-catenin. The expression of S100P mRNA and protein in endometrial cancer significantly increased and is associated with pathologic differenciation grade. S100P may promote endometrial cell proliferation by increasing nuclear translocation of β-catenin.
Keywords: S100P; c-myc; cyclinD1; endometrial cancer; proliferation; β-catenin.