Expression of CLDN1 and EGFR in PTC.

Papillary thyroid carcinoma (PTC) involves complex genetic mechanisms, notably involving CLDN1 and EGFR. This study investigates the expression and variations of these genes and their effects on tumor behavior and patient outcomes. Meta-analysis of CLDN1 and EGFR expression in TCGA-PTC patients and GEO datasets was conducted. cBioPortal was used for clinical analysis. GSEA, GO, KEGG, Hallmark pathways, and cibersort analysis were applied. Cell proliferation, migration, invasion, and apoptosis were assessed in vitro. Co-culturing with CD8 T cells, MTT assay, ELISA, subcutaneous tumor models, and immunohistochemistry were performed. TGF-β pathway-related proteins were analyzed via Western blot. CLDN1 and EGFR were overexpressed in PTC tumors, correlating with higher-risk patients and reduced CD8 T cell infiltration. Silencing these genes inhibited tumor cell functions and enhanced CD8 T cell activity, both in vitro and in vivo. CLDN1 and EGFR are crucial in PTC, linked to tumor invasiveness, EMT, and immune suppression, presenting them as potential therapeutic targets.