Wang Y M, Huang Y S, Ma Z H, Bu D F, Wang Y, Tu P, Li H
Department of Dermatology, Peking University First Hospital, Beijing, China; Beijing Key Laboratory of Molecular Diagnosis on Dermatoses, Beijing, China.
Clin Exp Dermatol. 2014 Oct;39(7):829-34. doi: 10.1111/ced.12411. Epub 2014 Sep 5.
Basal cell carcinoma (BCC) is a prevalent form of nonmelanoma skin cancer. Although numerous studies in white populations suggest that mutations in the TP53 gene play an important role in the development of BCC, it is not clear whether this is also the case in East Asian populations such as in China.
To investigate the frequency and the features of TP53 mutation in sporadic BCC in a Chinese population.
In total, 30 patients with sporadic BCC, who had previously taken part in a study on PTCH1 mutations, were enrolled. BCC and control cells were obtained by laser-capture microdissection, and DNA was amplified and sequenced for analysis of TP53 mutations.
In the 30 BCC samples, 6 TP53 point mutations were found (frequency of 20%), and 4 of these 6 mutations had ultraviolet (UV)-specific alterations. Combining these results with those of the previous study on PTCH1 mutations, we found that two patients with had three types of genetic alterations (each had two PTCH1 mutations and one TP53 point mutation). A further two patients each had one PTCH1 mutation and one UV signature TP53 mutation. In addition, the total number of UV-specific mutations of PTCH1 and TP53 accounted for 20% of the total patient group.
The incidence of TP53 mutation in BCC in our Chinese subjects was lower than that reported for white populations. Many of the patients carried mutations of other genes in addition to of TP53. The majority of TP53 mutations were UV-induced specific alterations. However, the results of the two studies on TP53 and PTCH1 indicated that the incidence of UV-specific mutations is much lower in Chinese than in white populations.
基底细胞癌（BCC）是一种常见的非黑素瘤皮肤癌。尽管在白种人群中进行的大量研究表明，TP53基因突变在BCC的发生发展中起重要作用，但在中国等东亚人群中情况是否如此尚不清楚。
调查中国人群散发性BCC中TP53突变的频率及特征。
共纳入30例曾参与PTCH1突变研究的散发性BCC患者。通过激光捕获显微切割获取BCC及对照细胞，对DNA进行扩增和测序以分析TP53突变。
在30个BCC样本中，发现6个TP53点突变（频率为20%），其中6个突变中有4个具有紫外线（UV）特异性改变。将这些结果与先前关于PTCH1突变的研究结果相结合，我们发现2例患者有三种类型的基因改变（每人有2个PTCH1突变和1个TP53点突变）。另外2例患者每人有1个PTCH1突变和1个UV特征性TP53突变。此外，PTCH1和TP53的UV特异性突变总数占患者总数的20%。
我们中国受试者BCC中TP53突变的发生率低于白种人群的报道。许多患者除TP53外还携带其他基因突变。大多数TP53突变是紫外线诱导的特异性改变。然而，关于TP53和PTCH1的两项研究结果表明，中国人中紫外线特异性突变的发生率远低于白种人群。
