Zhao Feng, Pan Shengli, Gu Yan, Guo Shanyu, Dai Qiancheng, Yu Yingyan, Zhang Wei
Department of Surgery, The Ninth People's Hospital of Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
Department of Surgery, Shanghai Ruijin Hospital of Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
PLoS One. 2014 Jan 28;9(1):e86486. doi: 10.1371/journal.pone.0086486. eCollection 2014.
HIC-1 is a gene that is hypermethylated in cancer, and commonly downregulated in human breast cancer. However, the precise mechanisms and molecular pathways regulated by HIC-1 remain unclear. We assessed HIC-1 expression on a tissue microarray containing 80 cases of breast cancer. We also analyzed its biological function by restoring HIC-1 expression using 5-aza-2' deoxycytidine (5-CdR) and small-activating RNAs for the reversal of HIC-1 tumor suppressive effects on MCF-7 and MDA-MB-231 cell lines. An Agilent Q44h global expressing microarray was probed after restoring the expression of HIC-1. Data demonstrated that HIC-1 expression was reduced significantly in breast cancer tissues. HIC-1 immunohistochemistry resulted in mean staining scores in cancer tissue and normal ductal epithelia of 3.54 and 8.2, respectively (p<0.01). 5-CdR partially reversed HIC-1 expression, and modulated cell growth and apoptosis. dsHIC1-2998, an saRNA, showed activating efficacy in breast cancer cells. A group of differentially expressed genes were characterized by cDNA microarray. Upon saRNA treatment, genes upregulated included those involved in immune activation, cell cycle interference, the induction of apoptosis, anti-metastasis, and cell differentiation. Downregulated genes included oncogenes and those that play roles in cell invasion, cell growth, and cell division. Our findings may provide valuable resources not only for gene functional studies, but also for potential clinical applications to develop novel drug targets.
HIC-1是一种在癌症中发生高甲基化且在人类乳腺癌中通常下调的基因。然而，HIC-1所调控的精确机制和分子途径仍不清楚。我们在包含80例乳腺癌病例的组织微阵列上评估了HIC-1的表达。我们还通过使用5-氮杂-2'-脱氧胞苷（5-CdR）恢复HIC-1表达以及使用小激活RNA来逆转HIC-1对MCF-7和MDA-MB-231细胞系的肿瘤抑制作用，分析了其生物学功能。在恢复HIC-1表达后，用安捷伦Q44h全球表达微阵列进行检测。数据表明，乳腺癌组织中HIC-1表达显著降低。HIC-1免疫组化在癌组织和正常导管上皮中的平均染色评分分别为3.54和8.2（p<0.01）。5-CdR部分逆转了HIC-1表达，并调节细胞生长和凋亡。dsHIC1-2998，一种小激活RNA，在乳腺癌细胞中显示出激活效果。通过cDNA微阵列对一组差异表达基因进行了表征。在小激活RNA处理后，上调的基因包括参与免疫激活、细胞周期干扰、凋亡诱导、抗转移和细胞分化的基因。下调的基因包括癌基因以及在细胞侵袭、细胞生长和细胞分裂中起作用的基因。我们的发现不仅可能为基因功能研究提供有价值的资源，也可能为开发新型药物靶点的潜在临床应用提供资源。
