PIK3CA and neoplasm: The loss of ATG6/Beclin1,one of the earliest characterized mammalian autophagy genes that suggested a tumor suppressionfunction for autophagy in certain mouse models of mammary oncogenesis [36-39], has been suggested to contribute toHER2 gene amplification as well as to alterations in PI3K andPTEN, two crucial downstream effectors of HER2 [40].