TNFRSF1B and nonpapillary renal cell carcinoma: As we were unable to obtain a sufficient number of ccRCC‐CD133+CSCs for immunoblotting isolated mitochondria, we isolated mitochondria from a ccRCC immortalized cell line (RCC‐26) treated with R2TNF or left UT and observed that R2TNF induced the expression of TNFR2 and pSTAT3Ser727 (Figure 4E).