Integrin α2 High Expression Of Ovarian Cancer Ascites Cells Leading To Drug-Resistance Via Upregulating ABCC1

Objective: This paper mainly studies the mechanism of high expression of integrin alpha 2 leading to chemotherapy resistance in ovarian cancer ascites cells.Methods: Primary ovarian cancer tissue and paired ascites were collected in sterile equipment of patients diagnosed with high-grade serous ovarian cancer(HGSOC), hospitaled in gynecologic oncology department of Tongji hospital affiliated with Tongji Medical College, Huazhong University of Science and Technology, then isolated and cultured these two kinds of cells, comparing the difference of morphology, proliferation and cisplatin resistance between the two. By using real-time fluorescence quantitative PCR(PCR Real-Time) to detect the difference of the drug resistance related genes in paired cancer cells, we found out that integrin alpha 2 increased significantly. After integrin alpha 2 was blocked by neutralizing antibody, we observed the changes of drug resistance. The relationship between integrin alpha 2 and drug resistance was verified by repeated experiments with human ovarian cancer cell line SKOV3 culturing in supernatant of ascites. The paired cancer cells were treated with doxorubicin, and the intracellular drug accumulation was observed under the fluorescence microscope. At the same time, we compared the differences of the intracellular drug content of SKOV3 under alpha 2 neutralizing antibody with or without the use of the supernatant of malignant ascites. The change of ABCC1 expression was observed after we knocked down integrin A2 gene expression, and used SKOV3 to verify. Tumor growth and survival rate was recorded of mice injected with drug resistant cell line SKOV3-G3-GFP to form tumor mess and treated with cisplatin together with or without integrin alpha 2 neutralizing antibody.Results: Ascites cells show quicker proliferation, lower apoptosis rate, more resistant to chemicals and higher expression of integrin alpha 2 compared with paired primary cancer cells. The drug-resistance effect can be reversed by integrin alpha 2 neutralizing antibody. The results are similar when we use SKOV3 cultured with malignant ascites supernatant instead. Ascites cells’ resistance to drugs is related to high expression of ABCC1, lowering the intracellular chemical content, which can be partly inhibited by integrin alpha 2 knock-down. The same results are acknowledged by using SKOV3. In vivo, injection of integrin alpha 2 neutralizing antibody together with chemicals can reduce chemotherapy-resistance and prolong survival.Conclusion: Ascites cells of high-grade serous ovarian cancer patients express high level of integrin alpha 2, which upregulatd ABCC1 expression, leading to chemical pumping out, lowering the intracellular drug content, thereby causing drug-resistance and bad prognosis.