SIRT1 and nonpapillary renal cell carcinoma: Regarding SIRT1, decreased expression levels was depicted by RCC compared to normal tissues, with 90.0% (27/30) of normal tissues displaying SIRT1 positivity, compared to 57.5% (23/40), p = 0.0033, and 71.8% (28/39), p = 0.0764, in ccRCC and pRCC, respectively (Figure 9B and Table S6).