ABSTRACT Aim This retrospective study investigates the interplay between epithelial‐mesenchymal transition (EMT) and immune response within the tumor microenvironment (TME) of oral squamous cell carcinoma (OSCC). Methodology Immunohistochemistry was conducted on OSCC specimens to evaluate the expression of podoplanin (PDP), E‐cadherin (CDH1), vimentin (VIM), fibronectin (FN), tenascin‐C (TNC), and vascular endothelial growth factor (VEGF). Cancer‐associated fibroblasts (CAFs) were identified by alpha‐smooth muscle actin (α‐SMA), and immune cells were quantified using CD66b for neutrophils and CD8 for T lymphocytes. Results Higher α‐SMA and moderate‐to‐strong VEGF expression were associated with reduced CDH1 and increased VIM and PDP expression ( p < 0.05), indicating an EMT‐like phenotype. Cases with elevated PDP—also linked to high α‐SMA—showed increased CD66b + cell density ( p = 0.072). VEGF expression additionally correlated with greater tumor thickness and depth of invasion ( p = 0.059). Strong TNC expression was associated with reduced CD8 + T‐cell infiltration in the tumor centre and increased CD66b + neutrophils ( p < 0.046). Strong FN expression was linked to a higher neutrophil‐to‐lymphocyte ratio ( p = 0.031). Elevated CD66b + cell counts and a higher neutrophil‐to‐lymphocyte ratio were both significantly associated with poorer overall survival ( p < 0.015). Conclusion These exploratory findings suggest that CAFs serve not only as a marker of stromal activation but may also contribute to immunomodulation and invasive tumor phenotype.
Lonni et al. (Thu,) studied this question.