Figure 2: Tarantula cubensis venom is more toxic for cancer cells. (A) Proliferation curves and related slope values. HEK293, MCF7 and HN5 cells were separately seeded and allowed to be cultured in the presence of 50 μg/ml of Theranekron® for 0, 6, 24 and 48 h. Then, the cell proliferation rates were assessed at the end of each period using MTT assay. Regression analysis was performed to evaluate related slope of each curve. Results showed very significant difference between the negative slopes. The order of proliferation subsidence was found as HN5>MCF7>HEK293. (B) Cell death curves and related slope values. The cells were cultured as described above and then percentage of dead cells was evaluated by trypan blue staining. Positive slope for each curve was assessed by applying regression analysis. Results showed very significant difference between the positive slopes. The order of cell death increase was found as HN5>MCF7>HEK293. Slope lines are indicated as dotted. *** p<0.001, **** p<0.0001.