Podoplanin expression in cancer‐associated fibroblasts predicts aggressive behavior in melanoma

Abstract

BACKGROUND: Recent studies have showed podoplanin expression in several tumors, which has been associated with lymph node metastasis and poor prognosis. Podoplanin expression in cancer-associated fibroblasts also correlates with tumor progression. However, the association of podoplanin expression with melanomas remains unclear. METHODS: To clarify the prognostic significance of podoplanin in melanoma, podoplanin expression in tumor cells and cancer-associated fibroblasts was examined by immunohistochemistry in tissue samples collected from 55 melanoma patients. RESULTS: Podoplanin expression in tumor cells was identified in 38 patients (69.1%) but did not show correlation with characteristics of tumor progression such as tumor thickness (p = 0.52) and sentinel lymph node (SLN) metastasis (p = 0.79). Podoplanin expression in cancer-associated fibroblasts was observed in 25 patients (45.5%), 11 of whom (44.0%) had SLN metastasis. In contrast, only 4 of 30 patients (13.3%) with podoplanin-negative cancer-associated fibroblasts exhibited SLN metastasis. Podoplanin-positive cancer-associated fibroblasts were associated with increased tumor thickness and SLN metastasis. Furthermore, patients with podoplanin-positive cancer-associated fibroblasts had poorer survival than those with podoplanin-negative cancer-associated fibroblasts (p = 0.0148). CONCLUSION: The presence of podoplanin expression in cancer-associated fibroblasts correlates with aggressive behavior in melanoma and might therefore serve as a useful prognostic factor for patients with melanoma.