Department of Gastroenterology, Huai'an No.1 Hospital, Affiliated to Nanjing Medical University, Huai'an, Jiangsu, 223300, China.
Pathol Oncol Res. 2012 Apr;18(2):471-7. doi: 10.1007/s12253-011-9470-z. Epub 2011 Nov 19.
Raf kinase inhibitory protein (RKIP, also PEBP1) is involved in regulation of multiple cellular signaling processes and suppressing metastasis in animal models. Downregulation of RKIP expression has been shown to promote tumor progression in a variety of human cancers. However, its role and clinical significance in resectable esophageal squamous cell carcinoma (ESCC) is still scanty. The purpose of this study was to investigate the prognostic significance of RKIP expression by immunohistochemistry in a group of patients with ESCC treated with surgical resection. RKIP expression in 233 surgically resected ESCC specimens and 49 cases of adjacent normal tissues was detected by using immunohistochemical staining. The clinical and prognostic significance of RKIP expression was statistically analyzed. Kaplan-Meier analysis was used to compare the postoperative survival between groups. Significant downregulation was noted for RKIP protein in ESCCs, compared to adjacent normal tissues (p < 0.001). A lower disease-free survival and overall survival of ESCC was found in patients whose tissues had low RKIP expression (both P < 0.001). In addition, RKIP expression could stratify the patient survival (disease-free survival/overall survival) in stage II (P = 0.01 and 0.02, repectively). The Cox proportionate hazard regression model also established that low expression of RKIP was significantly correlated with increased risk (RR = 3.572) of recurrence compared with high RKIP expression (P < 0.001). Furthermore, the results of multivariate analysis suggested that RKIP expression (P < 0.001) was an independent factor that affected overall survival. These findings suggest that the low expression of RKIP be associated with poor survival in resectable ESCC patients.
Raf 激酶抑制蛋白（RKIP，也称为 PEBP1）参与调节多种细胞信号转导过程，并在动物模型中抑制转移。RKIP 表达下调已被证明可促进多种人类癌症的肿瘤进展。然而，其在可切除食管鳞状细胞癌（ESCC）中的作用和临床意义仍然很少。本研究旨在通过免疫组织化学检测一组接受手术切除的 ESCC 患者中 RKIP 的表达，探讨其预后意义。采用免疫组织化学染色法检测 233 例手术切除的 ESCC 标本和 49 例相邻正常组织中 RKIP 的表达。统计分析 RKIP 表达的临床和预后意义。Kaplan-Meier 分析用于比较组间术后生存。与相邻正常组织相比，ESCC 中 RKIP 蛋白表达明显下调（p<0.001）。RKIP 表达较低的 ESCC 患者无病生存率和总生存率较低（均 P<0.001）。此外，RKIP 表达可分层患者生存（无病生存率/总生存率）在 II 期（P=0.01 和 0.02）。Cox 比例风险回归模型还确定，与高 RKIP 表达相比，低表达 RKIP 与复发风险增加显著相关（RR=3.572，P<0.001）。此外，多因素分析结果表明，RKIP 表达（P<0.001）是影响总生存率的独立因素。这些发现表明，在可切除的 ESCC 患者中，RKIP 表达降低与生存不良相关。
