Objective To screen the cytokines promoting estrogen secretion in endometrial cancer cells in tumor microenvironment, and to study the related mechanism.

Methods Stromal cells of endometrial carcinoma were isolated and identified by double immunofluorescence. The concentrations of estrogen and expression of aromatase in endometrial cancer cells (RL95-2, HEC-1A, and HEC-1B) were measured under the co-culture with stromal cells and individual culture modes. The differentially expressed cytokines were screened by cytokine chip and further verified by real-time PCR.

Results The vimentin in the extracted cells was positive, which indicated the extraction of tumor stromal cells was successful. The concentration of estrogen in the supernatant and the expression of aromatase in tumor cells in the co-culture group were significantly higher than that in the individual culture group (P < 0.01). The expression of growth differentiation factor-15 (GDF-15) in the supernatant of co-culture group was significantly higher than that in the individual culture group (P < 0.01), and the expression of aromatase in endometrial cancer cells was significantly upregulated by 10 ng/mL GDF-15(P < 0.01).

Conclusions Under the condition of co-culture of endometrial cancer cells and stromal cells, the expression of aromatase is significantly increased in endometrial cancer cells, which promotes the estrogen secretion in stromal cells, and GDF-15 in endometrial carcinoma cell might play an important role.