Immunotherapy and its early signs in the immune system

Tumor expression of programmed death-ligand 1 (PD-L1) and other biomarkers are recognized but insufficient to fully explain immunotherapy response rates.

• A significant percentage of patients exhibit resistance to immunotherapy despite the use of immune checkpoint inhibitors.
• Tumor mutational burden and mismatch repair deficiency are established predictive biomarkers but do not account for variability in treatment responses.
• The tumor microenvironment may influence the diversity and clonality of immune cells infiltrating tumors.
• Different checkpoint molecules play critical roles in activating cytotoxic T cells within the tumor microenvironment.
• Cytokines, chemokines, and growth factors, regulated by epigenetic factors, contribute to the complexity of immune interactions in tumors.
• New research is focusing on peripheral immune cells expressing PD-1/PD-L1 and soluble immune checkpoint molecules as potential predictive biomarkers.

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