Wound fluids collected from patients after IORT treatment activates extrinsic apoptotic pathway in MCF7 breast cancer cell line

Abstract

Objectives: Intraoperative radiotherapy (IORT) relates to irradiation of diseased tissue during the surgery within the tumor bed. The reason for this process is based on the fact that the increase in the radiation dose increases local tumor control. It was shown that postoperative fluids obtained from patients after breast cancer conserving surgery, stimulated motility and invasiveness of tumor cells in vitro. The results obtained from TARGIT clinical trial demonstrated that IORT significantly inhibits the stimulatory effect of wound fluids on tumor cells in vitro. We therefore speculated that wound fluids collected from patients after IORT treatment may induce the apoptosis in breast cancer cell lines and it may be a reason for their lower proliferation rate and potential to metastasis. Material and methods: Breast cancer MCF7 cell line was incubated with wound fluids collected from patients after conserving breast cancer surgery or surgery followed by IORT for 4 days. Then the expression of markers associated with extrinsic or intrinsic apoptosis pathway was established. Results: Our results clearly indicate activation of extrinsic apoptosis pathway by wound fluids collected from patients after IORT treatment. No changes in apoptotic markers were seen in cells treated with wound fluids collected from patients after the surgery alone. Conclusions: Thus we confirmed that wound fluids collected from patients after IORT treatment may induce the apoptosis in breast cancer cell lines and it may be a reason for their lower proliferation rate and invasiveness of tumor cells in vitro.