Effects of proteasome inhibitor bortezomib and cisplatin on 4t1 cancer cells

After cardiovasculer disesaes, cancer is the most common disease in our country and for many cancer types there is still no cure up to now. Therefore, in this study it has been examined that whether there are cytotoxic effects of bortezomib and cisplatin drugs either alone or in combination in 4T1 breast cancer cells. In the study 4T1 cells has been treated with different concentrations of cisplatin (200 µM; 100 µM; 50 µM; 10 µM; 1 µM; 0,5 µM; 0,1 µM or 0,01 µM) for 24 hours. Afterwards, % survival of cells has been obtained using MTT tests and IC50 values has been evaluated. According to this study, the IC50 value of cisplatin was found as 14,2 μM. Furthermore, the effects of combination of bortezomib and cisplatin in 4T1 cells has been examined. After 24 hours treatment with DMSO (control), 10 nM bortezomib, 50 nM bortezomib, 1 µM cisplatin, 5 µM cisplatin or with their combinations in 4T1 cells, % survival results were compared with control and with other groups. Soft agar assay has been applied to observe colony formation. Soft agar colony formation is a technique that shows cytotoxic and anti-tumor effects of drugs. Colony numbers in bortezomib + cisplatin treated combination group was observed to be less than that in DMSO (control), bortezomib or cisplatin treated groups. These results indicate that bortezomib and cisplatin combination may be more efficient than the individually treated drugs in cancer cure. Keywords: Apoptosis, bortezomib, cisplatin, proteasome, 4T1, % survival.