TNFRSF1A and nonpapillary renal cell carcinoma: We initially investigated whether TNF effects STAT3 phosphorylation in ccRCC‐CD133+ CSCs using a kidney tumor organ culture model and TNF receptor subtype‐selective muteins.4 Our data demonstrate that selective ligation of TNFR2 (not TNFR1) induce pSTAT3Ser727 but not pSTAT3Ty705 in resident CD133+CSCs in ccRCC.