Needle crystals of vitamin B2 induce polyploidy in Chinese hamster lung (CHL/IU) cells

Induction of polyploidy by vitamin B2 (VB2) was investigated in cultured Chinese hamster lung (CHL/IU) cells. We report that VB2 in the form of needle crystals induces polyploidy via the formation of CHL/IU cells with more than one nucleus. The incidence of polyploid cells depended on the amount of needle crystals. No induction of polyploidy was observed when VB2 was used in solution. Electron-microscopic examination revealed that needle crystals adhered to the cell surface, and were enclosed by viscous cellular materials. These results indicate that needle crystals of VB2 have the ability to induce polyploidy in cultured CHL/IU cells, probably by physically fixing the shape of the cells and by this preventing normal mitosis.