The pentose phosphate pathway (PPP) plays a significant role in regulating the growth of tumor cells by providing cells with ribose-5-phosphate and NADPH with the help of its key regulatory enzyme glucose-6-phosphate dehydrogenase (G6PD) and its rate-limiting enzyme 6-phosphogluconate dehydrogenase (6PGD) [79]. Here, G6PD is linked to neoplasm.