Merkel cells and Merkel cell carcinoma express the BCL-2 proto-oncogene.
The bel-2 proto-oncogene, which is involved in the regulation of apoptosis, is expressed in a wide variety of fetal and adult tissues. We and others have demonstrated recently that in the human skin melanocytes, nevus cells and melanoma cells express bcl-2 constitutively. In the present study, we have analysed the expression of bcl-2 in Merkel cells and in Merkel cell carcinomas. In 2 colour immunofluorescence staining, normal human Merkel cells as identified by the expression of cytokeratins 8, 18 and 20, were also anti-bcl-2 positive. Staining of paraffin sections of Merkel cell carcinomas with an anti-bcl-2 monoclonal antibody revealed strong bcl-2 protein immunoreactivity in all 5 tumors tested. Serial sections of Merkel cell carcinomas stained with the monoclonal antibodies CK 20, CAM 5.2, anti-neuron-specific enolase and anti-bcl-2 showed that the anti-bcl-2 reactive cells were indeed tumor cells. Our data demonstrate for the first time, that normal human Merkel cells and Merkel cel carcinomas express bcl-2 constitutively. Considering the biological function of the bcl-2 proto-oncogene, i.e., its anti-apoptotic effect, it is conceivable that in the near future, modulations of the expression of this protein may offer a new strategy in the therapy of bcl-2 expressing tumors such as Merkel cell carcinoma.
Plettenberg
A
A
Department of Dermatology, University of Vienna Medical School, Austria.
Pammer
J
J
Tschachler
E
E
D000328:Adult; D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D015266:Carcinoma, Merkel Cell / Q000378:metabolism / Q000473:pathology*; D005333:Fetus; D005385:Fingers; D015870:Gene Expression; D019254:Genes, bcl-2; D006801:Humans; D007150:Immunohistochemistry; D018862:Merkel Cells / Q000166:cytology* / Q000378:metabolism*; D000090063:Proto-Oncogene Mas; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D012016:Reference Values; D012878:Skin Neoplasms / Q000378:metabolism / Q000473:pathology*; D014034:Toes
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D019253:Proto-Oncogene Proteins c-bcl-2