Okudela K, Ito T, Kameda Y, Nakamura N, Kitamura H
Department of Pathology, Yokohama City University School of Medicine, Japan.
Histol Histopathol. 1999 Apr;14(2):479-85. doi: 10.14670/HH-14.479.
Small cell carcinoma is a rare neoplasm in the esophagus. To evaluate cell proliferation activity and its underlying mechanisms in this tumor, we examined immunohistochemically 5 cases of small cell carcinoma of the esophagus (SCCE) for expressions of tumor suppressor proteins, oncoproteins and cell proliferation markers including p53, p21WAF1/CIP1, retinoblastoma (Rb) protein, bcl-2, Ki-67 and PCNA, and compared the results with those of 5 cases of small cell carcinoma of the lung (SCCL) and 10 cases of squamous cell carcinoma of the esophagus (SQCE). The prevalence and labeling index of p53-immunoreactivity tended to be higher in SCCE (4/5; 56.6%) and SCCL (4/5; 79.9%) than in SQCE (6/10; 48.8%). Expression of p21WAF1/CIP1 was observed in 2 of 10 cases of SQCE. In contrast, its expression could not be detected in any cases of SCCE and SCCL examined. Expression of Rb protein was observed in 9 out of 10 cases of SQCE, but not in any cases of SCCE and SCCL. SCCE and SCCL showed more frequent and intense immunoreactivity for bcl-2 than SQCE. In expression of cell proliferation markers (Ki-67 and PCNA), no remarkable difference was observed among SCCE, SCCL and SQCE. These results suggest that SCCE and SCCL could share some genetic alternations including mutation of p53, loss of Rb gene and overexpression of bcl-2, and these may be related to the similar biological potentials between the two. Furthermore, SCCE was different from SQCE in expression of Rb protein and bcl-2, and these two types of esophageal carcinoma could arise through different molecular mechanisms.
小细胞癌是食管中一种罕见的肿瘤。为了评估该肿瘤中的细胞增殖活性及其潜在机制，我们对5例食管小细胞癌（SCCE）进行了免疫组织化学检查，以检测肿瘤抑制蛋白、癌蛋白和细胞增殖标志物（包括p53、p21WAF1/CIP1、视网膜母细胞瘤（Rb）蛋白、bcl-2、Ki-67和PCNA）的表达，并将结果与5例肺小细胞癌（SCCL）和10例食管鳞状细胞癌（SQCE）的结果进行比较。SCCE（4/5；56.6%）和SCCL（4/5；79.9%）中p53免疫反应性的发生率和标记指数往往高于SQCE（6/10；48.8%）。10例SQCE中有2例观察到p21WAF1/CIP1的表达。相比之下，在所检查的任何SCCE和SCCL病例中均未检测到其表达。10例SQCE中有9例观察到Rb蛋白的表达，但SCCE和SCCL的任何病例中均未观察到。SCCE和SCCL对bcl-2的免疫反应性比SQCE更频繁、更强。在细胞增殖标志物（Ki-67和PCNA）的表达方面，SCCE、SCCL和SQCE之间未观察到显著差异。这些结果表明，SCCE和SCCL可能共享一些基因改变，包括p53突变、Rb基因缺失和bcl-2过表达，这些可能与两者之间相似的生物学潜能有关。此外，SCCE在Rb蛋白和bcl-2的表达上与SQCE不同，这两种类型的食管癌可能通过不同的分子机制发生。
