PD-1 and beyond to Activate T Cells in Cutaneous Squamous Cell Cancers: The Case for 4-1BB and VISTA Antibodies in Combination Therapy

摘要

The use of checkpoint antibodies has revolutionized the treatment of cancer. Tumor-infiltrating T cells, key mediators of anti-tumor immune responses, are often actively silenced by the tumor microenvironment. Checkpoint antibodies block inhibitory signals or enhance positive signaling pathways in these T cells to overcome silencing, resulting in an improved anti-tumor T-cell response. To date, many clinical studies have focused on blocking inhibitory pathways (e.g., CTLA-4 and PD-1), with varying success. Increasingly, alternative checkpoint molecules are being identified and used as monotherapies, or in combination with existing PD-1/CTLA-4 treatments. This review dissects the potential role of checkpoint antibodies against PD-1, VISTA and 4-1BB in the future treatment of cutaneous skin cancers.