Barzilai A, Goldberg I, Yulash M, Pavlotsky F, Zuckerman A, Trau H, Azizi E, Kopolovic J
Department of Dermatology, Sheba Medical Center, Tel-Hashomer, Sacker Faculty of Medicine, Tel-Aviv University, Israel.
Am J Dermatopathol. 1998 Oct;20(5):473-7. doi: 10.1097/00000372-199810000-00008.
The nucleolar organizer regions (NORs) are chromosomal loops of DNA and proteins involved in ribosomal synthesis. By silver staining, they can be identified as black dots (AgNORs) in the nuclei. Their size and number reflect cell and nuclear activity. Therefore, AgNOR count may correlate with the proliferative activity of tumors. In malignant melanoma, correlation between AgNOR count and the growth phase was found. However, the value of AgNORs in determining prognosis is disputable. Our purpose was to evaluate the role of AgNORs in predicting the biological behavior of melanoma. Paraffin-embedded sections of 30 cases of primary melanoma, 0.4-5 mm thick (mean, 1.6 mm) were stained with silver. Follow-up of all patients was at least 5 years. For each tumor, at least 50 cells were randomly selected for AgNOR count at a final magnification of 500, and the mean of AgNOR content was calculated. Sample parameters corresponded well to the epidemiology and the natural history of melanoma. AgNOR counts (0.78-4.26; mean, 1.42+/-0.72) correlated with tumor thickness (p = 0.01); thus, most superficial tumors had low AgNOR counts, whereas most deep tumors (> or = 1.5 mm) showed high counts. Patients who had tumors with AgNOR counts lower than the median had longer disease-free interval (DFI) than did patients who had tumors with higher counts (p = 0.02). Furthermore, in a multivariate Cox analysis, AgNOR count was independent of tumor thickness in determining DFI (p = 0.05). Therefore, AgNORs may serve as a parameter to predict more accurately the progression of melanomas (mainly thin ones). Larger studies are needed in order to consolidate these preliminary results and to characterize AgNOR value further as a prognostic factor in melanoma.
核仁组织区（NORs）是参与核糖体合成的DNA和蛋白质的染色体环。通过银染，它们在细胞核中可被识别为黑点（AgNORs）。其大小和数量反映细胞和核活性。因此，AgNOR计数可能与肿瘤的增殖活性相关。在恶性黑色素瘤中，发现了AgNOR计数与生长阶段之间的相关性。然而，AgNORs在判断预后方面的价值存在争议。我们的目的是评估AgNORs在预测黑色素瘤生物学行为中的作用。对30例原发性黑色素瘤石蜡包埋切片（厚度0.4 - 5毫米，平均1.6毫米）进行银染。所有患者的随访时间至少为5年。对于每个肿瘤，在最终放大倍数为500时随机选择至少50个细胞进行AgNOR计数，并计算AgNOR含量的平均值。样本参数与黑色素瘤的流行病学和自然史相符。AgNOR计数（0.78 - 4.26；平均1.42±0.72）与肿瘤厚度相关（p = 0.01）；因此，大多数浅表肿瘤的AgNOR计数较低，而大多数深部肿瘤（≥1.5毫米）的计数较高。AgNOR计数低于中位数的肿瘤患者的无病生存期（DFI）比计数较高的患者更长（p = 0.02）。此外，在多变量Cox分析中，AgNOR计数在确定DFI时独立于肿瘤厚度（p = 0.05）。因此，AgNORs可作为一个参数，更准确地预测黑色素瘤（主要是薄型黑色素瘤）的进展。需要进行更大规模的研究以巩固这些初步结果，并进一步将AgNOR值表征为黑色素瘤的预后因素。
