Comparison of the Effect of Platinum (IV) Complexes on Spheroids and Monolayer Culture of HeLa Cells.

We performed a comparative study of the cytotoxicity of cisplatin, JM216 complex, and aminonitroxyl platinum(IV) complexes for HeLa cells grown in monolayer and 3D culture. The growth dynamics of spheroids was studied and optimal conditions for evaluation of cytotoxicity were determined. Spheroids were less sensitive to the test compounds than cells in a monolayer. The resistance index (RI) of spheroids was determined as the ratio of IC50 for spheroids to IC50 for monolayer culture. Resistance index was 5.0±1.5 for cisplatin and ranged from 1.8 to 2.3 for platinum(IV) complexes. The observed differences are related to different physicochemical properties of the complexes and different mechanisms of their penetration into cells.