Photodynamic priming with Vitamin D and ALA-based PDT induces intratumoral immune cell recruitment and signaling pathway activation in murine cutaneous squamous cell carcinoma.

ABSTRACT: Photodynamic therapy (PDT) is effective for early epithelial pre-cancers, yet its efficacy in fully-developed cutaneous squamous cell carcinoma (SCC) is limited by immunosuppression in the tumor microenvironment. Vitamin D (VitD) has emerged as a potential neoadjuvant to enhance photodynamic priming in several cancers. Here, we investigated how VitD pretreatment modulates local and systemic immune responses to aminolevulinic acid-based PDT in two immunocompetent murine SCC models (chronic UV-induced SCC, and subcutaneously implanted PDVC57B cells). VitD combined with PDT significantly amplified hallmarks of immunogenic cell death, including calreticulin and HMGB1 expression, and increased recruitment of neutrophils, macrophages, dendritic cells, and CD8⁺ T cells into tumors. Imp

SUBMITTER: Shen AS 

PROVIDER: S-EPMC12889683 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature