IGF1 and cancer: IGF-1 signaling has been found to be essential for maintaining cancer cell viability by stimulating mitochondrial biogenesis and turnover mainly through the induction of transcription activators, namely peroxisome proliferator-activated receptor γ coactivator 1β (PGC-1β) and PGC-1α-related coactivator (PRC), as well as the induction of BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 (BNIP3) accumulation in mitochondria, an important mediator of mitophagy [96].