Liao Yun, He Xiaoying, Qiu Haifeng, Che Qi, Wang Fangyuan, Lu Wen, Chen Zheng, Qiu Meiting, Wang Jingyun, Wang Huihui, Wan Xiaoping
Department of Obstetrics and Gynecology, Shanghai First Maternity and Infant Hospital Affiliated to Tong Ji University, No, 536, Changle Road, Shanghai 200080, China.
BMC Cancer. 2014 Jul 5;14:487. doi: 10.1186/1471-2407-14-487.
Mechanisms governing the metastasis of endometrial cancer (EC) are poorly defined. Recent data support a role for Enhancer-of-split and hairy-related protein 1 (SHARP1), a basic helix-loop-helix transcription repressor, in regulating invasiveness and angiogenesis of several human cancers. However, the role of SHARP1 in metastasis of EC remains unclear.
Human EC cell lines (Ishikawa and HEC-1B) were used. SHARP1 was upregulated by lentivirus transduction, while intracellular domain of NOTCH1 (ICN) were upregulated by transient transfection with plasmids. Effects of SHARP1 on cell migration and invasion were evaluated by wound healing assay and transwell invasion assay. Experimental metastasis assay were performed in nude mice. Effects of SHAPR1 on protein levels of target genes were detected by western blotting. Furthermore, the association between SHARP1 and the NOTCH1/EMT pathway was further verified in EC tissue specimens by immunohistochemical analysis.
Overexpression of SHARP1 in EC cells inhibited cell migration, invasion, and metastasis. Exogenous SHARP1 overexpression affected the proteins levels of genes involved in EMT process and NOTCH1 signaling pathway. Upregulation of ICN in SHARP1-overexpressing Ishikawa cells induced cell migration and an EMT phenotype. Additionally, immunohistochemical analysis demonstrated that SHARP1 protein levels were lower in metastatic EC than in primary tumors, and statistical analysis revealed correlations between levels of SHARP1 and markers of EMT and NOTCH1 signaling pathway in human EC tissue specimen.
This work supports a role for SHARP1 in suppressing EMT and metastasis in EC by attenuating NOTCH1 signaling. Therefore, SHARP1 may be a novel marker for lymphatic metastasis in EC patients.
子宫内膜癌（EC）转移的调控机制尚不清楚。最近的数据支持分裂增强子和毛相关蛋白1（SHARP1）（一种碱性螺旋-环-螺旋转录抑制因子）在调节几种人类癌症的侵袭性和血管生成中发挥作用。然而，SHARP1在EC转移中的作用仍不清楚。
使用人EC细胞系（Ishikawa和HEC-1B）。通过慢病毒转导上调SHARP1，而通过质粒瞬时转染上调NOTCH1的细胞内结构域（ICN）。通过伤口愈合试验和Transwell侵袭试验评估SHARP1对细胞迁移和侵袭的影响。在裸鼠中进行实验性转移试验。通过蛋白质印迹检测SHAPR1对靶基因蛋白质水平的影响。此外，通过免疫组织化学分析在EC组织标本中进一步验证SHARP1与NOTCH1/EMT途径之间的关联。
EC细胞中SHARP1的过表达抑制细胞迁移、侵袭和转移。外源性SHARP1过表达影响参与EMT过程和NOTCH1信号通路的基因的蛋白质水平。在过表达SHARP1的Ishikawa细胞中上调ICN可诱导细胞迁移和EMT表型。此外，免疫组织化学分析表明，转移性EC中SHARP1蛋白水平低于原发性肿瘤，统计分析显示人EC组织标本中SHARP1水平与EMT和NOTCH1信号通路标志物之间存在相关性。
这项工作支持SHARP1通过减弱NOTCH1信号通路在抑制EC的EMT和转移中发挥作用。因此，SHARP1可能是EC患者淋巴转移的新标志物。
