Potentiation Effect Of 5FU by Fragaceatoxin C Pore-Forming Toxin in MCF-7 Cell Line

Introduction: Chemotherapy has been restricted due to the high-dose side effects. In the present study, acceleration of the chemotherapeutic drug (5FU) entrance into MCF-7 cells has been explored by using a recombinant form of Fragaceatoxin C (FraC) pore-forming toxin. Methods: In this experimental study, the gene for FraC toxin was order from a commercial source and was sub-cloned into pET28a vector using NcoI and XhoI restriction enzymes. Expression of the protein was induced by IPTG and purification was performed using Ni-NTA affinity chromatography. Hemolysis was tested using a turbidimetric assay. Cytotoxic and potentiation effects of the recombinant toxin on 5FU chemotherapeutic drug were analyzed using trypan blue and MTT assays. T-student test was used to analyze the data using the SPSS v16 software. Significance was defined as P≤0.05 Results: Recombinant FraC toxin was produced in E. coli with 86% purity. Cytotoxic effects of the FraC toxin in MCF-7 cells were dose and time-dependent. the IC50 of FraC toxin on MCF-7 cells was 3.3 mg/ml. Non-toxic concentrations of recombinant FraC toxin enhanced cytotoxic effects of 5FU by a factor of 4 to 6 in different exposure times (24-72 h). Conclusion: Potentiation of the 5FU chemotherapeutic effect by acceleration of its entrance into cancer target cells using FraC pore-forming toxin can reduce its side effects of the chemotherapy.