Cell deformation and changes in mechanical properties, such as adhesion and elasticity modulus, are some of the most significant signs of cancer. This study evaluated the mechanical specifications of normal and cancerous (CT26) mouse colon cells before and after treatments. At first, the mechanical properties of the cells were obtained. As a result, the CT26 cell was softer than a healthy cell. The chemotherapy by Cisplatin drug increased the Young’s modulus of CT26 from 1.638 to 8.766 kPa (5.352 times) and 13.02 kPa (7.949 times) for 24- and 48-h cultures, respectively. Regarding Young’s modules, p values were lower than 0.05 in most cases. The plasma treatment increased the stiffness of CT26 cell for 24 h from 1.638 to 3.317 kPa (2.025 times) and 5.523 kPa (3.372 times) for 30 and 60 s of exposure and for 72 h to 20.67 kPa (12.619 times) and 23.77 kPa (6.359 times) for 30 and 60 s of exposure, respectively. Standard deviations varied from 0.489 to 5.56 kPa and from 0.338 to 0.529 nN for the stiffness and adhesion, respectively. Increasing the culture and exposure times increased the stiffness and cell rigidity but decreasing the cell migration. The width of CT26 cell was larger than that of a healthy cell (1.708 times). The results indicated that increasing cell stiffness increased the AFM beam resonant frequency. FEM showed that amounts of resonant frequencies change from 4189.21 to 4712.65, 32,854.69 to 36,692.54, and 102,268.13 to 107,157.39 Hz for the first three modes.