Department of Pediatric Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, People's Republic of China.
Onco Targets Ther. 2013 Dec 2;6:1751-60. doi: 10.2147/OTT.S52643. eCollection 2013.
Neuroblastoma (NB) is the most common solid extracranial tumor in children. However, the molecular mechanism and progression of NB is largely unknown, and unfortunately, the prognosis is poor. Src-associated in mitosis with a molecular weight of 68 kDa (Sam68) is associated with carcinogenesis and neurogenesis. The present study aimed to investigate the clinical and prognostic significance of Sam68 in NB.
The expression of Sam68 in immortalized normal epithelial cells, NB cell lines, and in four cases of paired NB tissue and adjacent normal tissue from the same patient was examined using Western blotting, reverse transcription-polymerase chain reaction (PCR) and real-time reverse transcription-PCR. The proliferation of NB cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, Sam68 protein expression was analyzed in 90 NB cases characterized as clinicopathological using immunohistochemistry. Statistical analyses were applied to evaluate the diagnostic value and associations of Sam68 with clinical parameters.
Western blotting and reverse transcription-PCR showed that the expression level of Sam68 was markedly higher in NB cell lines than in the immortalized normal epithelial cells at both messenger RNA and protein levels. The MTT assay revealed that Sam68 expression supported proliferation of NB cells. Sam68 expression levels were significantly up-regulated in tumor tissues in comparison to the matched adjacent normal tissues from the same patient. Sam68 protein level was positively correlated with clinical stage (P<0.001), tumor histology (P<0.001), and distant metastasis (P=0.029). Patients with higher Sam68 expression had shorter overall survival time, whereas those with lower tumor Sam68 expression had longer survival time.
Our results suggest that Sam68 expression is associated with neuroblastoma progression and may represent a novel and valuable predictor for prognostic evaluation of neuroblastoma patients.
神经母细胞瘤（NB）是儿童中最常见的颅外实体瘤。然而，NB 的分子机制和进展在很大程度上尚不清楚，且预后不良。与有丝分裂相关的Src 同源物 68kDa（Sam68）与致癌作用和神经发生有关。本研究旨在探讨 Sam68 在 NB 中的临床和预后意义。
采用 Western blot、逆转录-聚合酶链反应（RT-PCR）和实时 RT-PCR 检测永生化正常上皮细胞、NB 细胞系以及来自同一患者的 4 例配对 NB 组织和相邻正常组织中 Sam68 的表达。通过 3-(4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐（MTT）测定 NB 细胞的增殖。此外，采用免疫组织化学法分析 90 例 NB 病例的 Sam68 蛋白表达，这些病例的临床病理特征均已明确。统计分析用于评估 Sam68 的诊断价值及其与临床参数的相关性。
Western blot 和 RT-PCR 显示，Sam68 在 NB 细胞系中的表达水平在信使 RNA 和蛋白水平上均明显高于永生化正常上皮细胞。MTT 测定显示 Sam68 表达支持 NB 细胞的增殖。与同一患者的配对相邻正常组织相比，Sam68 表达水平在肿瘤组织中显著上调。Sam68 蛋白水平与临床分期（P<0.001）、肿瘤组织学（P<0.001）和远处转移（P=0.029）呈正相关。Sam68 表达较高的患者总生存时间较短，而 Sam68 表达较低的患者生存时间较长。
我们的结果表明，Sam68 表达与神经母细胞瘤的进展相关，可能代表一种新的、有价值的神经母细胞瘤患者预后评估预测因子。
