Wang Yuanyuan, Zang Wenqiao, Du Yuwen, Ma Yunyun, Li Min, Li Ping, Chen Xudong, Wang Tao, Dong Ziming, Zhao Guoqiang
College of Basic Medical Sciences, Zhengzhou University, No,100 Kexue Road, Zhengzhou, Henan 450001, China.
J Transl Med. 2013 Dec 6;11:301. doi: 10.1186/1479-5876-11-301.
MicroRNAs (miRNAs) can act as either oncogenes or tumor suppressor genes under different conditions and thus can play a significant role in cancer development. We investigated miR-655 expression in a cohort of esophageal squamous cell carcinoma (ESCC) to assess the impact of this miRNA on ESCC cell invasion and metastasis.
A qRT-PCR assay was used to quantify miR-655 expression levels in 34 paired ESCC samples and adjacent non-tumor tissues. Wound healing and transwell assays were used to evaluate the effects of miR-655 expression on the invasiveness of ESCC cells. Luciferase reporter and western blot assays were used to determine whether the mRNA encoding pituitary tumor-transforming gene-1 (PTTG1) is a major target of miR-655.
The expression level of miR-655 in ESCC tissues was found to be lower than in adjacent non-tumor tissues (P < 0.05). This relatively low expression level was significantly associated with the occurrence of lymph node metastases (P < 0.05). Migration rates were significantly lower for two ESCC-derived cell lines (EC9706 and KYSE150) transfected with miR-429 mimics (P < 0.05). Subsequent western blot and luciferase reporter assays demonstrated that miR-655 could bind to putative binding sites within the PTTG1 mRNA 3'-untranslated region (3'-UTR) and thus reduce the expression.
miR-655 is expressed at low levels in primary ESCC tissues, and up-regulation of miR-655 inhibits ESCC cell invasiveness by targeting PTTG1. Our findings suggest that PTTG1 may act as a major target of miR-655. This study improves our understanding of the mechanisms underlying ESCC pathogenesis and may promote the development of novel targeted therapies.
微小RNA（miRNA）在不同条件下可作为癌基因或肿瘤抑制基因，因此在癌症发展中发挥重要作用。我们研究了食管鳞状细胞癌（ESCC）队列中miR-655的表达，以评估该miRNA对ESCC细胞侵袭和转移的影响。
采用qRT-PCR检测34对ESCC样本及相邻非肿瘤组织中miR-655的表达水平。采用伤口愈合实验和Transwell实验评估miR-655表达对ESCC细胞侵袭性的影响。采用荧光素酶报告基因实验和蛋白质印迹实验确定垂体肿瘤转化基因1（PTTG1）的编码mRNA是否为miR-655的主要靶标。
发现ESCC组织中miR-655的表达水平低于相邻非肿瘤组织（P<0.05）。这种相对较低的表达水平与淋巴结转移的发生显著相关（P<0.05）。用miR-429模拟物转染的两种ESCC来源细胞系（EC9706和KYSE150）的迁移率显著降低（P<0.05）。随后的蛋白质印迹实验和荧光素酶报告基因实验表明，miR-655可与PTTG1 mRNA 3'-非翻译区（3'-UTR）内的假定结合位点结合，从而降低其表达。
miR-655在原发性ESCC组织中低表达，上调miR-655可通过靶向PTTG1抑制ESCC细胞的侵袭性。我们的研究结果表明，PTTG1可能是miR-655的主要靶标。本研究增进了我们对ESCC发病机制的理解，并可能促进新型靶向治疗的发展。
