The gated state of
anion channels is involved in the regulation of proliferation and migration of
tumors. Specific regulators are urgently needed for efficacious
cancer ablation. For this purpose, it is essential to understand the molecular mechanisms of interaction between the regulators and
anion channels and apply this knowledge to regulate
anion channels. Transmembrane 16A (TMEM16A) is the molecular basis of the
calcium-activated chloride channels. It is an
anion channel activated by Ca2+, and the inhibition of TMEM16A is associated with a decrease in
tumorigenesis. Herein, we characterized a natural compound
procyanidin (PC) as an efficacious and selective inhibitor of TMEM16A with an IC50 of 10.6 ± 0.6 μM. Our research revealed the precise sites (D383, R535, and E624) of electrostatic interactions between PC and TMEM16A. Near-infrared (NIR)-light-responsive photothermal conjugated
polymer nanoparticles encapsulating PC (CPNs-PC) were established to remotely target and regulate the TMEM16A
anion channel. Upon NIR irradiation, CPNs-PC downregulated the signaling pathway downstream of TMEM16A and arrested the cell cycle progression of
cancer cells and improved the bioavailability of PC. The
tumor inhibition ratio of CPNs-PC was superior to PC by 13.4%. Our findings enabled the development of a strategy to accurately and remotely regulate
anion channels to promote
tumor regression using NIR-light-responsive conjugated
polymer nanoparticles containing specific inhibitors of TMEM16A.