Kraemer K H, Herlyn M, Yuspa S H, Clark W H, Townsend G K, Neises G R, Hearing V J
Laboratory of Molecular Carcinogenesis, National Cancer Institute, Bethesda, Maryland 20892.
Arch Dermatol. 1989 Feb;125(2):263-8.
Patients with xeroderma pigmentosum (XP) have more than a 1000-fold increased risk of cutaneous melanoma. To determine if the XP DNA repair defect is present in cutaneous pigmentary cells, nevus cells and melanocytes from four large, pigmented nevi were cultured from a 12-year-old girl with XP. Cultured melanocytes showed dendritic morphologic features, contained mature melanosomes, and reacted with monoclonal antibody to tyrosinase. Nevus cells were spindle shaped and expressed nevus cell-associated antigens. Melanocytes, nevus cells, and dermal fibroblasts from the patient with XP all had a similar reduction in DNA repair: unscheduled DNA synthesis was 30% to 50% of that in normal fibroblasts following a 30 J/m2 ultraviolet dose. After a 6 J/m2 ultraviolet dose, the proliferative ability of XP nevus cells and fibroblasts was reduced to 10% of that of normal fibroblasts. This study indicates that cultured melanocytes and nevus cells express the characteristic XP DNA repair defect.
着色性干皮病（XP）患者患皮肤黑素瘤的风险增加1000多倍。为了确定XP的DNA修复缺陷是否存在于皮肤色素细胞中，从一名12岁患有XP的女孩身上培养了来自四个大的色素痣的痣细胞和黑素细胞。培养的黑素细胞呈现树突状形态特征，含有成熟的黑素小体，并与抗酪氨酸酶单克隆抗体发生反应。痣细胞呈纺锤形，表达与痣细胞相关的抗原。XP患者的黑素细胞、痣细胞和真皮成纤维细胞在DNA修复方面都有类似程度的降低：在30 J/m2紫外线剂量照射后，非预定DNA合成是正常成纤维细胞的30%至50%。在6 J/m2紫外线剂量照射后，XP痣细胞和成纤维细胞的增殖能力降至正常成纤维细胞的10%。这项研究表明，培养的黑素细胞和痣细胞表现出典型的XP DNA修复缺陷。
