Furthermore, in order to reduce the systemic toxicity, Wang and coworkers developed a nanoclustered cascaded enzymes by crosslinking GOx and CAT with a pH-responsive block polymer poly(ethylene glycol)-block-poly(2-hydroxyethyl methacrylate) bearing 2-(2-carboxyethyl)-3-methylmaleic anhydride (PEG-b-PHEMACMA) with a BSA/BSATPZ (wt:wt, 1:2) outer shell for cancer starvation and hypoxia-activated chemotherapy 94. This evidence concerns the gene HAO1 and cancer.