SIRT3 and neoplasm: SIRT3 expression showed significant associations with apoptotic and mitotic index, tumour extent, tumour stage and response to therapy (P = 0.022, 0.02, 0.042, 0.039 and 0.027) as positive SIRT3 expression was associated with the lower apoptotic index, higher mitotic index, more tumour extension into renal parenchyma and perirenal fascia, advanced tumour stage and worse response to chemotherapy (Table 4).