TIGIT in cancer immunotherapy.

Area of Science:

• Immunology
• Cancer Biology
• Immunotherapy

Background:

• Tumors employ immune escape mechanisms, leading to T cell dysfunction and exhaustion via checkpoint inhibitory receptors.
• Immunotherapies targeting PD-1 and CTLA-4 have shown clinical success in various solid tumors.
• Other inhibitory receptors are also targeted in immune checkpoint blockade therapy.

Purpose of the Study:

• To investigate the role of the T cell immunoreceptor with immunoglobulin and ITIM domain (TIGIT) pathway in cancer immune evasion.
• To evaluate the efficacy of dual PD-1/TIGIT blockade in enhancing anti-tumor immunity.

Main Methods:

• Analysis of TIGIT expression on immune cells (T cells, NK cells, Tregs) and its ligands (CD155, CD112) in the tumor microenvironment.
• In vitro studies assessing the impact of TIGIT blockade on T cell and NK cell function.
• In vivo studies using mouse tumor models to evaluate tumor rejection following dual PD-1/TIGIT blockade.

Main Results:

• TIGIT is upregulated on immune cells and interacts with CD155 and CD112 expressed by tumor cells and antigen-presenting cells.
• The TIGIT pathway regulates T cell- and NK cell-mediated tumor recognition.
• Dual PD-1/TIGIT blockade significantly enhanced tumor antigen-specific CD8+ T cell expansion and function in vitro.
• Combined PD-1 and TIGIT blockade promoted tumor rejection in preclinical mouse models.

Conclusions:

• The TIGIT pathway represents a promising target for cancer immunotherapy.
• Dual blockade of PD-1 and TIGIT demonstrates potent anti-tumor activity and warrants further clinical investigation.
• Ongoing clinical trials are evaluating the efficacy of dual PD-1/TIGIT blockade in cancer patients.