Identification of the methylation related genes in gastric cancer

胃癌甲基化相关基因的鉴定

基本信息

批准号：
18590333
负责人：
YOSHIKAWA Yasuji
金额：
$ 2.39万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

项目摘要

In order to identify bradn-new methylation associated molecules, we performed pharmacological unmasking microarray assay subsequent to the addition of inhibitory agents for deacetylation as well as the demethylating agent. Simultaneously, we performed Laser Microdissection assay to identify cancer cell specific repressed genes in comparison to the corresponding norIn order to identify bradn-new methylation associated molecules, we performed pharmacological unmasking microarray assay subsequent to the addition of inhibitory agents for deacetylation as well as the demethylating agent. Simultaneously, we performed Laser Microdissection assay to identify cancer cell specific repressed genes in comparison to the corresponding normal counter part. The microarray analysis (Agilent Technology, 12,814 genes) was performed with gastricd cancer cells extracted specifically by LMD. Therefore, we obtained overlapped gene expression profiles between methylated genes and cancer cell respressed genes. … More Then, this combined method enabled us to uncover 34 genes those might be occult cancer suppressor genes.Among identified 34 genes, we focused on Fhll gene. By real time quantitative RTPCR assay and immunohistochemical analysis, Fhll expression was significantly downregulated in gastric cancer cells. This result was consistent with the previous reports that Fhll expression was suppressed in various types of malignancies. Concerning regulation mechanism of Fhll expression, Shen Y., et. al. identified Fhll gene as downstream of Crk-associated substrate (Cas) signaling network. According to their reports, Fhll expression appears to be down regulation by phosphorylated Cas in this network. Additionally, many studies have indicated that Cas signaling network promotes cancer development. Among them, Brabek J., et. al. demonstrated that activation of Cas network drove cancer cells to increase their capacity of invasiveness by in vivo assay. Taken together with the evidence that Fhll gene acts cancer suppressor effects by maintaining intercellular junction, it is suggested that Cas signaling network blocks Fhll to achieve its role, resulting in the collapse of intercellular junction. Loss of cell-to-cell communication is the first step for tumor progression. In fact, our survival curves plotted by Kaplan-Meier method demonstrated that patients with all lower expression tumor showed shorter survive, due to deeper tumor invasion or more frequent distant metastasis: Reduced expression of Fhll may be a molecular trigger to aecelerate tumor invasion and migration through Cas signaling network.The most intriguing aspect of this study is positive correlation between Fhll lower expression and the incidence of distant metastasis. It is indeed that multivariate analysis demonstrated that Fhll lower expression was not an independent indicator for distant metastasis. However, loss of Fhll expression was more closely correlated with distant metastasis. As a matter of fact, there are several reports concerning inverse relationshio between Fhl1 expression and distant metastasis. For instance, La Tulippe E., et. al. reported that the result of gene expression profiling comparing primary prostate cancers with metastatic prostate cancers using microarray analysis demonstrated that Fhl1 was under expressed in metastatic cancers. Additionally, it was reported that Fhl1 expression in metastatic site was down-regulated compared with that in the matched normal mucosa regarding breast cancer and malanoma. Taken these above reports into consideration, it is suggested that loss of Fhl1 expression in cancer cells play a crucial role in acquisition of metastatic propensitesOur serial study revealed the evidence that of Fhl1 expression in primary site of gastric cancer, not metastatic site, may be more reliable indicator for distant metastatis than venous permeation. Because the incidence of distant metastasis is the most influential factor for clinical outcome, it is important for the manaferment of gastric cancer patients to detect the presence of distant metastasis with accuracy. However, it is difficult to estimate increased ability of distant metastasis from pathologically venous permeation evaluated on sections routinely stained with hematoxylin-eosin, and Fhl1 lower expression in primary site may be a powerful diagnostic modality to predict metastatic propensity of gastric cancer cells more easily and accurately.In conclusion, this current study revealed that clinicopathologic significances of Fhl1 expression in gastric cancer. Fhl1 expression was down-regulated in gastric cancer, ant the patients with Fhl1 lower expression tumor showed survive due to inverse relationship between Ghl1 expression and poor prognostic factor such as deeper tumor invasion and more frequent distant metastasis. Although Fhl1 lower expression was not an independent indicator for distant metastasis by multivariate analysis, it was more significantly correlated with distant metastasis than venous permission. Loss of expression Fhl1 expression may be a potencial indicator for distant metastasis in gastric cancer. Less

为了鉴定Bradn新甲基化相关的分子，我们对添加抑制剂进行脱乙酰基化以及脱甲基化剂后进行了药理学揭露微阵列测定。同时，我们进行了激光显微解剖测定法，与相应的Norin顺序相比，鉴定癌细胞特异性代表的基因，以鉴定Bradn-New甲基化相关分子，我们对抑制性抑制剂的脱乙酰化剂和脱甲基剂的抑制剂进行了药理学识别微阵列测定。同时，我们进行了激光显微解剖测定法，以鉴定癌细胞特异性抑制基因与相应的正常计数器相比。微阵列分析（Agilent Technology，12,814个基因）是用特异性LMD提取的胃癌细胞进行的。因此，我们获得了甲基化基因和癌细胞抑制基因之间的重叠基因表达谱。 …更多然后，这种合并的方法使我们能够发现34个基因可能是神秘的抑制癌基因。在鉴定出34个基因，我们专注于FHLL基因。通过实时定量RTPCR分析和免疫组织化学分析，FHLL表达在胃癌细胞中显着下调。该结果与以前的报道一致，即在各种类型的恶性肿瘤中抑制了FHLL表达。关于FHLL表达的调节机制，Shen Y.等。 al。将FHLL基因识别为与CRK相关底物（CAS）信号网络的下游。根据他们的报道，FHLL表达似乎是通过该网络中磷酸化的CAS的调节。此外，许多研究表明，CAS信号网络促进了癌症的发展。其中，Brabek J.，ET。 al。证明CAS网络的激活推动了癌细胞通过体内测定增加其侵入性的能力。与证据表明，FHLL基因通过维持细胞间交界处作用抑制癌症抑制剂的作用，建议CAS信号网络阻断FHLL以实现其作用，从而导致细胞间连接的崩溃。细胞到细胞通信的丧失是肿瘤进展的第一步。实际上，我们由卡普兰 - 梅尔方法绘制的我们的生存曲线表明，由于较深的肿瘤入侵或更频繁的远处转移，表现出所有较低表达肿瘤的患者生存较短：FHLL的表达降低可能是通过CASENTIRE CASSIGNT网络的AECELEMEREME肿瘤入侵和迁移的分子触发。转移。确实，多元分析表明，FHLL较低的表达但是，FHLL表达的丧失与远处转移更加紧密相关。事实上，有几份有关FHL1表达与远处转移之间关系反比关系的报告。例如，La Tulippe E.等。 al。报道说，使用微阵列分析的基因表达分析比较初级前列腺癌与转移性前列腺癌的结果表明，FHL1在转移性癌症中表达。此外，据报道，与在乳腺癌和肾瘤中匹配的正常粘膜中相比，转移性位点中的FHL1表达下调。考虑到这些上述报告，建议在癌细胞中FHL1表达的丧失在获取转移性Promentesour序列研究中起着至关重要的作用，表明证据表明，胃癌原发性部位而不是转移性部位的FHL1表达，而不是转移性部位，可能更可靠地指示转移的指标。由于独特的转移的事件是临床结果的最具影响力因素，因此对于胃癌患者的强迫症的强化很重要。然而，很难估计在常规上用苏木精 - 烯烃染色的切片评估的病理静脉渗透的能力提高能力，而初级部位中FHL1较低的表达可能是一种有力的诊断方式，可以预测胃癌细胞的转移性更容易，准确地进行癌症。在胃癌中，FHL1表达下调，ANT患有FHL1较低表达肿瘤的患者与GHL1表达和预后不良因子之间的反相关关系存活，尽管FHL1较低的表达不是通过多变量分析区分转移的独立指标，而是与疏远的转移相关，而不是与VENOS的持久性相关。表达FHL1表达的丧失可能是区分胃癌转移的潜在指标。较少的