CASC3 and cancer: Wang et al. (2015) reported a pH-responsive polymer based on a polyamide dendrimer, which is functionalized by the catechol group inside the dendrimer and achieves the “off-on” release of BTZ in the slightly acidic tumor microenvironment through catechol–borate dynamic covalent bonding interactions with BTZ, allowing the therapeutic effect of BTZ in cancer treatment to be maintained while reducing its adverse reactions.