H6PD and cancer: Moreover, the cytotoxicity of the tested samples in human hepatoma cell line HepG2; the leakage of the cytoplasmic lactate dehydrogenase (LDH) enzyme [26]; and the modulation of the glucose-6-phosphate dehydrogenase (G6PDH) enzyme, involved in the pentose phosphate pathway (PPP) and in the regulation of the cell transformation and cancer proliferation [27], were investigated.