Proliferation, apoptosis, and survivin expression in a spectrum of melanocytic nevi

Area of Science:

• Dermatopathology
• Molecular Biology
• Oncology

Background:

• Apoptosis is crucial for tissue balance and is often altered in skin cancers.
• Survivin, an apoptosis inhibitor, is present in various skin tumors but its role in melanocytic nevi was unstudied.
• Melanocytic nevi are common benign skin growths of melanocyte origin.

Purpose of the Study:

• To investigate the expression pattern of survivin in different types of benign melanocytic nevi.
• To compare survivin expression with markers of cell proliferation and apoptosis in these nevi.
• To understand the role of survivin in the pathogenesis of benign melanocytic lesions.

Main Methods:

• In situ hybridization was used to detect survivin expression in six types of melanocytic nevi.
• Apoptotic index was assessed using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL).
• Proliferating cell nuclear antigen (PCNA) immunostaining was employed to determine the proliferation index.

Main Results:

• Survivin was expressed in all evaluated benign melanocytic nevi, including compound dysplastic, intradermal, compound, neurotized intradermal, and Spitz nevi.
• The apoptotic rate was low across most nevi types, with no apoptotic cells detected in neurotized nevi.
• Spitz nevi exhibited the highest proliferation index, while other nevi showed minimal proliferation.

Conclusions:

• Consistent survivin expression in benign melanocytic lesions suggests its involvement in their development.
• The rare identification of apoptotic cells points to a potential dysregulation of apoptotic pathways.
• These findings imply that impaired apoptosis contributes to cell accumulation in benign melanocytic neoplasms.