ABSTRACT
Aim To explore the effect of ferroptosis inducer Erastin combined with Shikonin on the anti-tumor activity of colorectal cancer cells and its mechanism.Methods Erastin(0,4,8,16,32,64 μmol·L-1)and Shikonin(SW-480:0, 0.5,1,2,4,8 μmol·L-1 with SW-620:(0,0.2,0.4,0.8,1.6,3.2 μmol·L-1)alone and 10 μmol·L-1 Erastin combined with various concentrations of Shikonin were used to treat colorectal cancer cells SW480 and SW620; Cell viability was detected by CCK-8 method and the apoptosis was detected by AnnexinV/PI double staining.The changes of active oxygen content in colorectal cancer cells were measured by ROS detection kit, and the changes of intracellular lactic acid content in SW480 and SW620 were measured by 10 μmol·L-1 Erastin alone or in combination with 2 μmol·L-1 and 1 μmol·L-1 Shikonin, respectively.The protein expressions of Bax, Bcl-2, PARP1, Caspase3,Caspase8,AKT and P-akt in SW480 and SW620 cells were detected by Western blot.Results The results of CCK-8 showed that the combination group could significantly inhibit the viability of colorectal cancer cells and the apoptotic rate was the highest.At the same time, lactic acid was inhibited most obviously.The content of intracellular reactive oxygen species and apoptosis-related proteins also changed significantly.Conclusions Erastin combined with Shikonin can synergistically induce the apoptosis of colorectal cancer cells.The mechanism may be inhibiting the production of lactic acid in tumor cells, increasing the content of reactive oxygen species in tumor cells, inhibiting the AKT signaling pathway, and activating pro-apoptotic proteins to induce colorectal cancer cell apoptosis.