Expression of the apoptosis-related oncogenes bcl-2, bax, and p53 in Merkel cell carcinoma: Can they predict treatment response and clinical outcome?

• Published in: Human pathology Vol. 30; no. 11; pp. 1367 - 1372
• Main Authors: Feinmesser, Meora, Halpern, Marisa, Fenig, Eyal, Tsabari, Cohava, Hodak, Emmilia, Sulkes, Jaqueline, Brenner, Baruch, Okon, Elimelech
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.11.1999; Elsevier
• Subjects: Adult; Age Factors; Aged; Aged, 80 and over; Apoptosis; bcl-2-Associated X Protein; Biological and medical sciences; Carcinoma, Merkel Cell - diagnosis; Carcinoma, Merkel Cell - metabolism; Carcinoma, Merkel Cell - pathology; Carcinoma, Merkel Cell - therapy; Dermatology; Female; Humans; Immunohistochemistry; Lymphatic Metastasis; Male; Medical sciences; Merkel cell carcinoma; Middle Aged; proapoptotic and antiapoptotic genes; Prognosis; Proto-Oncogene Proteins - biosynthesis; Proto-Oncogene Proteins c-bcl-2 - biosynthesis; Sex Factors; Skin Neoplasms - diagnosis; Skin Neoplasms - metabolism; Skin Neoplasms - pathology; Skin Neoplasms - therapy; treatment; Treatment Outcome; Tumor Suppressor Protein p53 - biosynthesis; Tumors of the skin and soft tissue. Premalignant lesions; proapoptotic and antiapoptotic genes; treatment; Merkel cell carcinoma; apoptosis; MCC; wt; HPF; Human; Immunohistochemistry; Skin disease; Carcinoma; Prognosis; Merkel cell; Malignant tumor; Gene expression; Response; Pathology; TP53 Gene; Treatment; Skin; Apoptosis; Tumor suppressor gene
• ISSN: 0046-8177; 1532-8392
• DOI: 10.1016/S0046-8177(99)90070-9

Chemotherapy and radiation therapy act predominantly through the induction of apoptosis in malignancies. Merkel cell carcinoma, an aggressive malignancy with prominent apoptosis, has proved to be sensitive to both modes to a certain degree. We used immunohistochemical methods to examine 25 Merkel cell carcinomas and 8 of their lymph node metastases to assess the status of the antiapoptotic gene bcl-2 and 2 proapoptotic genes, wild-type p53 and bax. All tumors showed prominent bax immunopositivity; 76% were positive for bcl-2, and only 28% were positive for p53, the latter presumably reflecting mutated p53. No statistically significant relationship was found between tumor immunopositivity and therapy response or survival. The widespread bax immunopositivity and the apparently low rate of p53 mutations, as suggested by the low rate of p53 immunopositivity, may be related to the presence of prominent apoptosis in Merkel cell carcinoma. The finding of bcl-2 immunopositivity in 76% of the tumors suggests that some of the tumor cells may be resistant to apoptosis-inducing agents.