Frey Lídia M, Houben Roland, Bröcker Eva-B
Department of Dermatology, Venerology and Allergology, University of Würzburg, 97080 Würzburg, Germany.
J Skin Cancer. 2011;2011:349726. doi: 10.1155/2011/349726. Epub 2010 Sep 29.
Basal cell carcinoma (BCC) is the most common neoplasm in the Caucasian population. Only a fraction of BCC exhibits pigmentation. Lack of melanocyte colonization has been suggested to be due to p53-inactivating mutations in the BCC cells interfering with the p53-proopiomelanocortin pathway and the production of alpha melanocyte-stimulating hormone in the tumor. To evaluate this, we determined tumor pigmentation as well as expression of melan-A and of p53 in 49 BCC tissues by means of immunohistochemistry. As expected, we observed a positive relation between tumor pigmentation and melan-A positive intra-tumoral melanocytes. Melanocyte colonization and, to a lesser extent, p53 overexpression showed intraindividual heterogeneity in larger tumors. p53 overexpression, which is indicative of p53 mutations, was not correlated to melanocyte colonization of BCC. Sequencing of exon 5-8 of the p53 gene in selected BCC cases revealed that colonization by melanocytes and BCC pigmentation is neither ablated by p53 mutations nor generally present in BCCs with wild-type p53.
基底细胞癌（BCC）是白种人最常见的肿瘤。只有一小部分BCC表现出色素沉着。有人认为，缺乏黑素细胞定植是由于BCC细胞中的p53失活突变干扰了p53-阿片促黑素皮质素原途径以及肿瘤中α黑素细胞刺激素的产生。为了对此进行评估，我们通过免疫组织化学方法测定了49个BCC组织中的肿瘤色素沉着以及Melan-A和p53的表达。正如预期的那样，我们观察到肿瘤色素沉着与肿瘤内Melan-A阳性黑素细胞之间呈正相关。在较大的肿瘤中，黑素细胞定植以及在较小程度上的p53过表达显示出个体内异质性。指示p53突变的p53过表达与BCC的黑素细胞定植无关。对选定BCC病例的p53基因第5-8外显子进行测序发现，黑素细胞定植和BCC色素沉着既不会因p53突变而消除，也不会普遍存在于具有野生型p53的BCC中。
