The invention belongs to the technical field of biological medicines, particularly relates to the technical direction of cooperation of medical
oncology treatment and
immunotherapy, and provides application of
crotonic acid and / or crotonyl-
coenzyme A in preparation of medicines for treating tumors. It is confirmed for the first time that
crotonic acid can inhibit proliferation and migration of various
solid tumor cells including
breast cancer,
liver cancer and
colorectal cancer, the inhibition effect of crotonyl
coenzyme A on
breast cancer metastasis is defined, the research blank of crotonyl
coenzyme A and crotonyl coenzyme A in the field of tumor treatment is filled, and short-chain
fatty acid and short-chain fatty-
acyl coenzyme A anti-tumor substance libraries are enriched. Meanwhile, it is proved that
crotonic acid can up-regulate expression of
tumor tissue PD-L1, when the crotonic acid is combined with the PD-L1
monoclonal antibody, the
cancer suppression effect is remarkably better than that of independent medication, the
immunotherapy effect is improved, the applicable crowd is expanded, and a novel treatment substance with a broad-spectrum
cancer suppression effect and a synergistic
treatment strategy are provided.