Development of drug resistance in cancer cells

Abstract Introduction/Objective The purpose of this study was to evaluate omeprazole treament in cancer cells. Methods/Case Report The colorectal cancer cell line, CACO2, was treated with omeprazole at two different concentrations and methotrexate as a positive control for 3-4 months. Using exon-spanning primers for the ABCG2 and ABCB1 genes, qPCR was used to monitor changes in mRNA expression of the efflux pumps, Breast Cancer Resistant Protein (BCRP) and P-glycoprotein (Pgp). Upregulation of BCRP and Pgp was observed through the western blot assay. Once overexpression of BCRP was confirmed, the omeprazole-treated and methotrexate-treated cells were tested for chemotherapy-resistance using the Prestoblue proliferation assay and were compared to the untreated cells. The omeprazole treatments were repeated for reproducibility using two esophageal cancer cell lines. The treated cells were also studied for expression changes of possible drug resistant and cancer genes using RNASeq analysis. Results (if a Case Study enter NA) N/A Conclusion Esophageal cancer patients, who are treated for acid reflux, may be at higher risk for developing chemotherapy-resistant/multidrug resistance (MDR) tumor cells prior to chemotherapy treatment. Esophageal cancer patients with MDR tumors will have lower chance of survival compared to patients who are responsive to chemotherapy treatment. By identifying the overexpression of BCRP in the tumor cells of cancer, oncologists will be able to use a better treatment plan with more effective chemotherapy drugs.