肝细胞癌是严重危害人类健康的恶性肿瘤之一，早期诊断能有效降低其死亡率。甲胎蛋白是应用最广泛的肝细胞癌血清蛋白标志物，但其检测灵敏度和特异性一直备受争议。本课题组前期研究发现分泌蛋白Dickkopf-1（DKK1）在肝细胞癌患者癌组织和血液中高表达，并通过大规模临床多中心Ⅱ期试验研究，发现血清蛋白DKK1可有效诊断肝细胞癌，尤其是早期肝细胞癌和甲胎蛋白阴性肝细胞癌。基于前期结果，本项目设计了肿瘤标志物临床Ⅲ期纵向回顾性研究，即从一随访16年（1996-2012）的队列中，收集已患肝癌患者自纳入队列至患癌之间每年的血样，以及自治疗至肝细胞癌复发或死亡之间每年的血样，检测血清DKK1蛋白浓度，评估其是否能早于现有诊断手段提示患癌风险，及其对肝细胞癌的预后价值。为使该基础研究成果转化为临床应用，本项目同时拟研发具有自主知识产权的DKK1蛋白酶联免疫检测试剂盒，为肝细胞癌诊断和预后提供新的有效工具。

Hepatocellular carcinoma (HCC) is one of the malignant cancers which threaten the human health. Early diagnosis is an effective approach to decrease the death rate. Alpha-fetoprotein (AFP) is the most widely used serum protein marker for HCC. However, its sensitivity and specificity are unsatisfied so far. We previously found a secreted protein, Dickkopf-1 (DKK1), was overexpressed in the cancerous tissues and sera of the patients with HCC. Using a large-scale multicenter phase Ⅱ study, we found that serum DKK1 had the capability to diagnose HCC, especially early-stage HCC and HCC with negative AFP (≤20 ng/mL). Based on our previous results, we design a phase Ⅲ retrospective longitudinal repository study to further evaluate the significance of DKK1 for the diagnosis and prognosis of HCC. In a cohort which the participants were followed up from 1996 to 2012 (16 years), blood samples of the HCC patients were collected from the year of enrollment to the year of tumor detection, and from the year of therapy to the year of tumor recurrence or death. Serum DKK1 concentrations will be measured by ELISA, in order to assess whether DKK1 can diagnose HCC before the clinical diagnosis and predict HCC recurrence and survival. Furthermore, for translating our basic research to clinical application, we also plan to develop an ELISA kit for DKK1 protein detection with our own intellectual property and it may provide a useful tool for the diagnosis and prognosis of HCC.

肝细胞癌是严重危害人类健康的恶性肿瘤之一，早期诊断能有效降低其死亡率。甲胎蛋白是应用最广泛的肝细胞癌血清蛋白标志物，但其检测灵敏度和特异性一直备受争议。本研究中，我们首先检测了DKK1在肝细胞系、肝癌细胞系以及具有不同转移潜能的肝癌患者中的表达情况，结果显示DKK1在转移性肝癌中高表达，其表达升高对肝癌复发和转移具有提示作用。我们还在包含390人的队列中（其中包括89例肝癌，36例肝硬化，65例慢性肝炎，及200例健康人血清）分析了DKK1与AFP，OPN三种标志物联合使用对肝癌的诊断价值。结果发现三种标志物联合使用可以显著提高对肝癌的早期诊断价值。此外，我们还首次运用自主研发的磁微粒化学发光免疫分析法验证了血清DKK1在肝细胞癌诊断中的价值，尤其对AFP阴性的HCC患者有较高的检出率，DKK1联合AFP检测可显著提高HCC诊断的敏感性及准确度。综上，血清DKK1检测可为肝细胞癌诊断和预后提供新的有效工具。