Assessment of Genotoxic Effects by Constructing a 3D Cellular System with Highly Sensitive Mutagenic Human-Hamster Hybrid Cells

Owing to complex microenvironmental conditions, it is challenging to reflect the actual biological responses of tissues or the body in a two-dimensional (2D) cellular system. In the present study, a low-attachment-cultivation technique was employed to establish a highly sensitive 3D human-hamster hybrid (A(L)) model to study the mutagenic effects of environmental pollutants. The results showed that the established 3D system has apparent organizational characteristics. The average diameter and average cell number of the 3D cells were approximately 240 mu m and 1500, respectively. The expression of stemness and cell-junction genes (biomarkers for 3D cells) was higher than that in 2D cells. The present study analyzed the mutagenic effects of the environmental carcinogens arsenite and silver nanoparticles using the established 3D system to demonstrate its efficiency in mutagenic assessment. The results showed that the mutagenic effects of arsenite (10 mu M) and silver nanoparticles (10 mu g/mL) were 70 +/- 3 and 99 +/- 7 per 10(5) survivors, respectively. These values were much lower than those from 2D A(L) cells and comparable to those from the in vivo system. These results suggest that the developed 3D-cell-culture model based on the 2D A(L) cellular system more effectively reflects the actual gene-mutation frequency of mutagens in vivo.