CD274 and nonpapillary renal cell carcinoma: After confirming the specific, and direct interaction between TGF-β1 and MSA, we investigated the effect of MSA treatment on the expression of TGF-β1, PD-L1 and VEGF by the non-sarcomatoid ccRCC cell line, 786-O, and the sarcomatoid ccRCC cell line, RCJ41T1; each chosen because they express high levels of TGF-β1, PD-L1 and VEGF.