Study on the molecular diagnosis of metastasis and recurrence and molecular targeted therapy for intractable hepato-pancreatic cancer

根据对肝细胞癌临床标本的DNA微阵列分析，极光激酶B被确定为唯一独立的致死性复发预测因子。临床前试验表明，极光激酶B的特异性抑制剂是治疗侵袭性肝癌的有前景的药物，其独特的基因表达特征与肝细胞癌的形态进展密切相关。特别是，干细胞标记物EpCAM可能在融合型多结节型肝癌的侵袭性中起关键作用。在核微环境中转运系统的变化中，我们利用肝细胞癌组织的微阵列分析了Importin家族。研究表明：(1)肿瘤特异性高甲基化介导的miR-124和miR-203沉默是原发性肝癌中较为常见的分子事件；(Ii)miR-124和miR-203通过下调其潜在靶点的表达抑制细胞生长，导致细胞周期分别停滞于G1、S检查点和细胞凋亡。我们发现非癌肝组织中细胞色素P1A2表达下调是早期肝癌复发的预测因素。采用前瞻性多中心队列的验证性研究证实了非癌性CYP1A2的重要性。GSEA显示，CYP1A2与肝组织中的氧化应激途径密切相关。我们使用蛋白酶体活性水平的荧光标记系统来鉴定具有肿瘤干细胞(CSCs)特征的胰腺癌细胞。我们筛选并鉴定了一种对胰腺干细胞有特殊毒性的化合物。

According to the DNA microarray analysis using clinical samples of hepatocellular carcinoma(HCC), aurora kinase B was identified as the only independent predictor of the lethal recurrence. Preclinical tests revealed the specific inhibitor of aurora kinase B was the promising agent to treat the aggressive HCC.The distinct signature of gene expression closely related to the morphological progression in HCC. Especially, a stem cell marker EpCAM might play a critical role in the aggressiveness of confluent multinodular type of HCC.Among the alterations of transport system in the nuclear microenvironment, we focused on the importin family using microarray analysis of HCC tissues. Importin alpha1 was identified as a molecule activated functionally in HCC cells, and its significance was also validated clinicopathologically.The study showed that(i) tumor-specific hypermethylation-mediated silencing of miR-124 and miR-203 was a relatively frequent molecular event in primary HCCs and(ii) miR-124 and miR-203 exert cell growth-inhibitory effect with the downregulation of their potential targets, resulting in cell cycle arrest at the G1 S checkpoint and apoptosis, respectively.We identified the downregulation of CYP1A2 in non-cancerous liver tissue as a predictive factor for recurrence of early-stage HCC. The significance of non-cancerous CYP1A2 was confirmed by validation study using the prospective multi-center cohort. GSEA revealed that close association of CYP1A2 was implicated with the oxidative stress pathways in liver tissue.We used a fluorescence marker system for level of proteasome activity to identify pancreatic cancer cells with features of cancer stem cells(CSCs). We screened and identified a compound that is specifically toxic to the pancreatic CSCs.