Novel Checkpoints and Cosignaling Molecules in Cancer Immunotherapy

Area of Science:

• Immunology
• Oncology
• Pharmacology

Background:

• Checkpoint protein inhibition, particularly targeting the programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway, has led to approved cancer therapies.
• Successes in melanoma and lung cancer have expanded to other malignancies, indicating broad therapeutic potential.
• PD-1 is one of numerous T-cell checkpoints and regulatory molecules that, when dysregulated in cancer, affect costimulatory and coinhibitory signaling.

Purpose of the Study:

• To review emerging checkpoint and cosignaling molecules for cancer immunotherapy.
• To highlight agents in early clinical development and late preclinical stages.
• To discuss potential therapeutic strategies involving these novel targets, alone or in combination.

Main Methods:

• Review of current literature and clinical trial data on novel immune checkpoint inhibitors and cosignaling molecules.
• Focus on targets within the immunoglobulin superfamily and tumor necrosis factor receptor superfamily.
• Emphasis on agents that have reached clinical trials or are in advanced preclinical development.

Main Results:

• Identification of numerous T-cell cosignaling receptors (29 from immunoglobulin superfamily, 26 from TNF receptor superfamily) as potential therapeutic targets.
• Several novel checkpoints and cosignaling molecules are progressing through early clinical development.
• Combinatorial approaches involving these agents with PD-1/PD-L1 blockade, CTLA-4 blockade, or chemotherapy are being explored.

Conclusions:

• The landscape of cancer immunotherapy is expanding beyond PD-1/PD-L1 blockade to include a wider array of checkpoint and cosignaling pathways.
• These novel targets offer significant potential for developing next-generation cancer therapeutics.
• Further clinical investigation is warranted to establish the efficacy and safety of these agents in various cancer types and combinations.