Instead, the similar pattern of the metabolic response of normal and cancer cells to IR strongly suggested that the mitochondrial shutdown might rather be a consequence of the physical effects induced by IR resulting in secondary changes in cellular bioenergetics, rather than altered activation of metabolic enzymes AMPK, SIRT3, or PARP1 described in response to IR (Fouquerel et al., 2014; Liu et al., 2015; Sanli et al., 2010). This evidence concerns the gene PARP1 and cancer.