We used the RT4 cell lines harboring the PPARγ-T475M mutation to demonstrate that, like PPARG WT amplification in SD48 and UMUC9 cells7 and RXRα -S427F mutation in HT11978,13 cells, PPARγ mutations render tumor cell growth PPARγ-dependent and regulate PPARγ target genes expression. The gene discussed is RXRA; the disease is neoplasm.