Hodak E, Hammel I, Feinmesser M, Zelinger A, Maron L, Sulkes J, David M
Department of Dermatology, Rabin Medical Center, Petah Tikva, Israel.
Am J Dermatopathol. 1999 Apr;21(2):138-45. doi: 10.1097/00000372-199904000-00005.
In many neoplasms, the finding p53 immunoreactivity correlates with striking cytologic atypia, a high tumor cell proliferation rate, and poor prognosis. The literature regarding p53 and Ki-67 (a nuclear proliferation-associated antigen) immunoreactivity in Kaposi's sarcoma is limited. We aimed to: (1) evaluate the role of p53 in the development of Kaposi's sarcoma; (2) determine whether there is a correlation between p53 and Ki-67 protein expression; and (3) determine possible differences between classical Kaposi's sarcoma, known usually to have a benign course, and iatrogenic Kaposi's sarcoma, the course of which is unpredictable, by studying the differential expression of p53 and Ki-67. Among 26 cases of classic KS and 19 of iatrogenic KS, 12 were classified histopathologically as early type and 33 as mixed or spindle-cell type. P53 and Ki-67 immunoreactivity correlated significantly with the histopathologic stage of KS (r=0.63, p=0.0001; r=0.42, p=0.0084, respectively). P53 was not detected in any of the cases in an early histopathologic stage but was present in 55% of the cases in a more advanced stage. The spindle cells increased in proportion with the histopathologic progression and were more often positive (p=0.019) and displayed more extensive staining than the endothelial cells (p=0.0001). There was a strong positive correlation between p53 and Ki-67 protein expression (r=0.43, p=0.0087). There was no correlation between the expression of either p53 or Ki-67 and the extent of the eruption. The expression of p53 and Ki-67 was significantly lower in iatrogenic cases than in the classic cases (p=0.009, p=0.0014, respectively), although no statistical difference was found between the histopathologic stages in the two clinical forms of KS. P53 immunoreactivity was detected in 79% of the cases of classic Kaposi's sarcoma in the mixed or spindle cell stage but in only 21.5% of the iatrogenic cases showing the same histopathologic stage (p=0.001), and the percentage of spindle cells as well as the endothelial cells expressing p53 was higher in the classic cases than in the iatrogenic cases (p=0.0032, p=0.0142, respectively). We conclude that p53 immunoexpression is a marker of tumor progression in classic Kaposi's sarcoma but not in most cases of iatrogenic Kaposi's sarcoma. The proliferative activity of the tumor cells in classic Kaposi's sarcoma is much higher than in iatrogenic Kaposi's sarcoma. Our work implies that the molecular steps involved in classic and iatrogenic Kaposi's sarcoma differ.
在许多肿瘤中，p53免疫反应性的发现与显著的细胞异型性、高肿瘤细胞增殖率及不良预后相关。关于卡波西肉瘤中p53和Ki-67（一种核增殖相关抗原）免疫反应性的文献有限。我们旨在：（1）评估p53在卡波西肉瘤发生发展中的作用；（2）确定p53与Ki-67蛋白表达之间是否存在相关性；（3）通过研究p53和Ki-67的差异表达，确定通常病程为良性的经典卡波西肉瘤与病程不可预测的医源性卡波西肉瘤之间可能存在的差异。在26例经典卡波西肉瘤和19例医源性卡波西肉瘤中，12例组织病理学分类为早期类型，33例为混合或梭形细胞类型。p53和Ki-67免疫反应性与卡波西肉瘤的组织病理学分期显著相关（分别为r = 0.63，p = 0.0001；r = 0.42，p = 0.0084）。在组织病理学早期阶段的任何病例中均未检测到p53，但在更晚期阶段的病例中有55%检测到。梭形细胞比例随组织病理学进展增加，且比内皮细胞更常呈阳性（p = 0.019），染色更广泛（p = 0.0001）。p53与Ki-67蛋白表达之间存在强正相关（r = 0.43，p = 0.0087）。p53或Ki-67的表达与皮疹范围之间无相关性。医源性病例中p53和Ki-67的表达显著低于经典病例（分别为p = 0.009，p = 0.0014），尽管在卡波西肉瘤的两种临床类型的组织病理学分期之间未发现统计学差异。在混合或梭形细胞阶段，79%的经典卡波西肉瘤病例检测到p53免疫反应性，但在显示相同组织病理学分期的医源性病例中仅21.5%检测到（p = 0.001），经典病例中表达p53的梭形细胞及内皮细胞百分比高于医源性病例（分别为p = 0.0032，p = 0.0142）。我们得出结论，p53免疫表达是经典卡波西肉瘤肿瘤进展的标志物，但在大多数医源性卡波西肉瘤病例中并非如此。经典卡波西肉瘤中肿瘤细胞的增殖活性远高于医源性卡波西肉瘤。我们的研究表明，经典和医源性卡波西肉瘤所涉及的分子步骤不同。
