The three-tails approach as a new strategy to improve selectivity of action of sulphonamide inhibitors against tumour-associated carbonic anhydrase IX and XII

Human (h) carbonic anhydrase (CAs, EC 4.2.1.1) isoforms IX and XII were recently confirmed as anticancer targets against solid hypoxic tumours. The three-tails approach has been proposed as an extension of the forerunner tail and dual-tail approach to fully exploit the amino acid differences at the medium/outer active site rims among different hCAs and to obtain more isoform-selective inhibitors. Many three-tailed inhibitors (TTIs) showed higher selectivity against the tumour-associated isoforms hCA IX and XII with respect to the off-targets hCA I and II. X-ray crystallography studies were performed to investigate the binding mode of four TTIs in complex with a hCA IX mimic. The ability of the most potent and selective TTIs to reduce in vitro the viability of colon cancer (HT29), prostate adenocarcinoma (PC3), and breast cancer (ZR75-1) cell lines was evaluated in normoxic (21% O-2) and hypoxic (3% O-2) conditions demonstrating relevant anti-proliferative effects.

Automated summary

Human carbonic anhydrase isoforms IX and XII have been confirmed as anticancer targets, with three-tails approach showing higher selectivity against tumor-associated isoforms and demonstrating anti-proliferative effects in various cancer cell lines. X-ray crystallography studies have been conducted to investigate the binding mode of these inhibitors, providing valuable insights for potential cancer treatments.