Effects of natural ligands and synthetic triorganotin compounds of nuclear retinoid X receptors in human MCF-7 breast cancer cell line.

In the present study, we analyzed in vitro effects of natural and synthetic triorganotin ligands of nuclear retinoid X receptors in human MCF-7 breast cancer cells. Our data has shown that all-trans retinoic acid significantly reduced expression of RXRalpha mRNA, Bcl2 and enhanced expression of BAX proteins. Tributyltin bromide markedly decreased mRNA level of RXRalpha and RXRbeta. Significantly reduced levels of both RXRs proteins were observed after treatment with tributyltin chloride (TBT-Cl) but not after treatment with triphenyltin chloride (TPT-Cl) for RXRbeta protein. Both RXRalpha and RXRbeta protein levels decrease was found also by combination ATRA+TBT-Cl/TPT-Cl.