Ramsay J A, From L, Kahn H J
Department of Medicine, Women's College Hospital, University of Toronto, Ontario, Canada.
Mod Pathol. 1995 Feb;8(2):150-4.
Since the discovery of bcl-2 proto-oncogene in follicular lymphomas, the protein product has been detected in a variety of normal tissues including skin, where it is expressed in basal keratinocytes. Recent studies indicate that bcl-2 protein is detected in nonlymphoid malignancies such as neuroblastoma and carcinomas of the lung and prostate. This study investigates the presence of bcl-2 protein in benign and malignant melanocytic neoplasms of the skin. Immunohistochemical analysis of bcl-2 protein expression was performed on 39 nevi and 60 malignant melanomas, including 21 metastases. There was diffuse strong immunopositivity for bcl-2 protein in 100% of nevi and 65% (43/60) of primary and metastatic melanomas. bcl-2 protein was diffusely expressed in 67% (30/39) of primary melanomas and 54% (11/21) of metastases. Although bcl-2 immunoreactivity was observed in all levels of primary cutaneous malignant melanomas, in 43% (9/21) of deep melanomas (Clark level > or = III), and 100% (7/7) of thick tumors (thickness > or = 4.00 mm), there was focal loss of immunoreactivity. Metastatic melanomas showed focal loss of bcl-2 expression in 10% (2/21) of cases and total loss of bcl-2 protein in 39% (8/21). We conclude from our results that bcl-2 protein is expressed by benign and malignant melanocytic tumors of the skin, but there is loss of bcl-2 protein expression with increasing tumor progression.
自从在滤泡性淋巴瘤中发现bcl-2原癌基因以来，已在包括皮肤在内的多种正常组织中检测到该蛋白产物，它在基底角质形成细胞中表达。最近的研究表明，在非淋巴恶性肿瘤如神经母细胞瘤以及肺癌和前列腺癌中也能检测到bcl-2蛋白。本研究调查皮肤良性和恶性黑素细胞肿瘤中bcl-2蛋白的存在情况。对39例痣和60例恶性黑色素瘤（包括21例转移瘤）进行了bcl-2蛋白表达的免疫组织化学分析。100%的痣以及65%（43/60）的原发性和转移性黑色素瘤中bcl-2蛋白呈弥漫性强免疫阳性。bcl-2蛋白在67%（30/39）的原发性黑色素瘤和54%（11/21）的转移瘤中呈弥漫性表达。尽管在原发性皮肤恶性黑色素瘤的各个层面均观察到bcl-2免疫反应性，但在43%（9/21）的深部黑色素瘤（Clark分级≥III级）和100%（7/7）的厚肿瘤（厚度≥4.00 mm）中，存在免疫反应性的局灶性缺失。转移性黑色素瘤在10%（2/21）的病例中显示bcl-2表达局灶性缺失，在39%（8/21）的病例中bcl-2蛋白完全缺失。我们从结果中得出结论，皮肤良性和恶性黑素细胞肿瘤表达bcl-2蛋白，但随着肿瘤进展，bcl-2蛋白表达会缺失。
