Recent advances in the role of endogenous hydrogen sulphide in cancer cells

Hydrogen sulphide (H(2)S) is a gaseous neurotransmitter that can be self‐synthesized by living organisms. With the deepening of research, the pathophysiological mechanisms of endogenous H(2)S in cancer have been increasingly elucidated: (1) promote angiogenesis, (2) stimulate cell bioenergetics, (3) promote migration and proliferation thereby invasion, (4) inhibit apoptosis and (5) activate abnormal cell cycle. However, the increasing H(2)S levels via exogenous sources show the opposite trend. This phenomenon can be explained by the bell‐shaped pharmacological model of H(2)S, that is, the production of endogenous (low concentration) H(2)S promotes tumour growth while the exogenous (high concentration) H(2)S inhibits tumour growth. Here, we review the impact of endogenous H(2)S synthesis and metabolism on tumour progression, summarize the mechanism of action of H(2)S in tumour growth, and discuss the possibility of H(2)S as a potential target for tumour treatment.