Title:Small-Molecule Drugs in Immunotherapy
Volume: 23
Issue: 13
Author(s): Xuanrun Hao, Zhongliang Chen, Haining Li, Minqin Wei, Zhili Zuo and Qing Su*
Affiliation:
- School of Pharmacy, Chengdu Medical College, Chengdu 610500, China
Keywords:
Cancer immunotherapy, inhibitors, Pd-1/Pd-L1 inhibitor, IDO inhibitor, STING agonists, RORγt agonists, TGF- β inhibitors.
Abstract: Immunotherapy has been increasingly used in the treatment of cancer. Compared with
chemotherapy, immunotherapy relies on the autoimmune system with fewer side effects. Small
molecule immune-oncological medicines usually have good bioavailability, higher tissue and tumor
permeability, and a reasonable half-life. In this work, we summarize the current advances in the
field of small molecule approaches in tumor immunology, including small molecules in clinical trials
and preclinical studies, containing PD1/PD-L1 small molecule inhibitors, IDO inhibitor, STING
activators, RORγt agonists, TGF-β inhibitors, etc. PD-1/DP-L1 is the most attractive target at present.
Some small molecule drugs are being in clinical trial studies. Among them, CA-170 has attracted
much attention as an oral small molecule drug. IDO is another popular target after PD-1/PDL1.
The dual IDO and PD-1 inhibitor can improve the low response of PD-1 and has a good synergistic
effect. STING is a protein that occurs naturally in the human body and can enhance the body's
immunity. RORγt is mainly expressed in cells of the immune system. It promotes the differentiation
of Th17 cells and produces the key factor IL-17, which plays a key role in the development of autoimmune
diseases. TGFβ signaling exhibits potent immunosuppressive activity on the coordinate
innate and adaptive immunity, impairing the antitumor potential of innate immune cells in the tumor
microenvironment. It is worth mentioning that immunotherapy drugs can often achieve better effects
when used in combination, which will help defeat cancer.