SIRT7 and cancer: BC is the most common malignancy throughout the world and is the fifth leading cause of cancer-related deaths.394 SIRT2 and SIRT4 are downregulated,395,396 while SIRT1 and SIRT7 are upregulated in BC tissues compared to adjacent tissues or normal tissues.357,397 Besides, increased SIRT2 and SIRT4 expression is correlated with longer overall survival,395,396 whereas increased SIRT1 and SIRT7 expression predicts a poor prognosis in patients with BC.398,399 These disparities might be in respect to the different roles of them in BC progression.400