Effect of letrozole combined with testosterone on the proliferation and apoptosis of endometrial carcinoma cells

Objective: To investigate the effect of the androgen testosterone on Ishikawa endometrial cancer (EC) cells in the presence of the aromatase inhibitor letrozole. Methods: Cultured Ishikawa EC cells were divided into three treatment groups: testosterone plus letrozole, testosterone alone and letrozole alone. The respective groups were treated for 48 h with these agents at final concentrations of 0.5, 1, 1.5, 2 or 2.5 µmol/L. The effect of combined letrozole and testosterone treatment was determined by MTT assay and flow cytometry. The effects of combined treatment on cell proliferation and apoptosis were also measured, while the concentration of estrogen in the culture solution was measured after treatment at a concentration of 2.5 µmol/L. Results: Inhibition of proliferation in the testosterone plus letrozole group increased with the concentration of these agents, with maximal inhibition observed at 2.5 µmol/L. Similarly, the rate of apoptosis increased with increasing concentration in the combined testosterone plus letrozole group. The proliferation and apoptosis rates were different between the three different testosterone and letrozole groups, while the estrogen concentration of the testosterone plus letrozole group was significantly lower that of the testosterone group. Conclusion: The androgen testosterone has anti-proliferative and pro-apoptotic effects on EC cells.

Endometrial cancer; Androgen; Antitumor; Proliferation; Apoptosis

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