Experimental testing of chemoresistance of ovarian cancer tumor cells

One of the most challenging issues in the treatment of ovarian cancer is the high level of tumor cell chemoresistance, which leads to early tumor recurrence and low overall survival. In the case of tumor cell chemoresistance, the therapy is ineffective, resulting in unnecessary drug consumption and harm to the patient due to toxic side effects and time losses during its implementation. One approach to solving this problem is experimental predictive testing of tumor cell chemoresistance in vitro.
Aim. To develop a protocol of experimental testing of chemoresistance of ovarian cancer cells to chemotherapy drugs. We analyzed changes in the number of viable cells of A-1847, Ovcar-3 and Ovcar-4 cell lines cultured in hypo-adhesive conditions and optimized a method of cell viability determination based on resazurin metabolism. It was shown that viability of ovarian cancer cells of the studied cell lines is approximately the same in the presence of 1^st and 2^nd line antitumor drugs measured in accordance with the developed culture protocol in hypo-adhesive conditions and using ATP-tumor chemosensitivity assay (ATP-TCA) (DCS Innovative Diagnostik-Systeme, Germany) approved for use in clinical practice. The developed method is based on readily available and inexpensive reagents and expendables which makes it economically attractive.

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