Figure 7: Cartoon illustrating key bioenrgetic changes in NSCLC cells. Cancer cells exhibit enhanced expression levels of the rate-limiting heme biosynthetic enzyme, 5-aminolevulinic acid synthase (ALAS), and the heme uptake proteins HCP1 and HRG-1. The increased heme availability in cancer cells leads to increased levels of various oxygen-utilizing hemoproteins, such as cytochrome c, cytoglobin, Cox-2 and cytochrome P450. The increase in these hemoproteins ultimately leads to intensified oxygen consumption, which provides ample energy to fuel the progression of NSCLC cells. [4,10].