Immunohistochemical Evaluation of Suprabasin, Isthmin-1, and Podocalyxin Immunoreactivity in Malignant Melanoma and Melanocytic Nevus

Abstract

Background and Aim Melanocytic nevi are common benign melanocytic proliferations, whereas malignant melanoma is an aggressive tumor with increasing incidence worldwide. Suprabasin (SBSN), isthmin-1 (ISM-1), and podocalyxin (PODXL) have been implicated in tumor development and progression. This study aimed to evaluate and compare the immunohistochemical expression of SBSN, ISM-1, and PODXL in malignant melanoma, melanocytic nevus, and normal skin. Materials and Methods The study included 20 malignant melanoma, 20 melanocytic nevus, and 20 normal skin samples archived at the Department of Pathology. Immunohistochemical staining was performed using antibodies against SBSN, ISM-1, and PODXL. Histoscores were calculated based on staining intensity and distribution. Statistical analyses were conducted using SPSS v22.0, and p < 0.05 was considered significant. Results SBSN and ISM-1 expression levels were significantly lower in malignant melanoma compared to both control and melanocytic nevus groups (p < 0.05), whereas both markers showed significantly increased expression in the melanocytic nevus group. PODXL expression was significantly higher in the malignant melanoma and melanocytic nevus groups compared to controls (p < 0.001). No statistically significant difference in PODXL expression was observed between the malignant melanoma and melanocytic nevus groups (p = 0.780). Conclusion Decreased SBSN and ISM-1 expression and increased PODXL expression may be associated with melanocytic lesion biology. However, since PODXL expression did not differ significantly between nevi and melanoma, its role in malignant transformation remains unclear.. These findings suggest that SBSN, ISM-1, and PODXL may play potential roles in the pathogenesis of melanocytic lesions and could provide useful insights for future studies investigating molecular mechanisms of melanoma progression.