Hughes J H, Robinson R A
Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City, USA.
Mod Pathol. 1995 Jun;8(5):526-9.
p53 is a tumor suppressor gene whose protein product is overexpressed in several human tumors. In this study we used a monoclonal antibody (DO7) direct against p53 and a previously described antigen retrieval methodology to examine p53 expression in 27 cases of microinvasive squamous cell carcinoma of the skin and in 10 cases of Bowen's disease. Immunohistochemical studies were performed on formalin-fixed, paraffin-embedded tissue sections that had been microwave-heated to improve antigenicity. Positive nuclear staining for p53 was observed in 23 of 27 (85%) cases of microinvasive squamous cell carcinoma and in five of 10 (50%) cases Bowen's disease. With the exception of occasional focal positive staining of basal layer cells, no p53 immunoreactivity was observed in normal skin. Our results demonstrate that increased expression of the p53 protein is a common finding in both in situ and microinvasive squamous cell carcinoma of the skin, and they suggest that loss of normal p53 tumor suppressor activity may be an important mechanism of oncogenesis in these neoplasms.
p53是一种肿瘤抑制基因，其蛋白质产物在多种人类肿瘤中过度表达。在本研究中，我们使用针对p53的单克隆抗体（DO7）和先前描述的抗原修复方法，检测了27例皮肤微浸润性鳞状细胞癌和10例鲍温病中p53的表达情况。对经微波加热以提高抗原性的福尔马林固定、石蜡包埋组织切片进行免疫组织化学研究。在27例微浸润性鳞状细胞癌中有23例（85%）观察到p53核阳性染色，在10例鲍温病中有5例（50%）观察到p53核阳性染色。除偶尔基底细胞层有局灶性阳性染色外，在正常皮肤中未观察到p53免疫反应性。我们的结果表明，p53蛋白表达增加在皮肤原位和微浸润性鳞状细胞癌中均常见，提示正常p53肿瘤抑制活性的丧失可能是这些肿瘤发生的重要机制。
