Li Hua, Xu Xin, Liu Yang, Li Shunle, Zhang Di, Meng Xiaofen, Lu Le, Li Yiming
Department of General Surgery, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China.
Anticancer Agents Med Chem. 2018;18(14):2010-2016. doi: 10.2174/1871520619666181203111329.
Gastric adenocarcinoma is one of the most common and lethal cancer types and is known as the second leading cause of cancer-related death of Asian adults, early diagnosis based on either pathology or molecular biology could be one of the most efficient ways to improve the outcomes of gastric adenocarcinoma patients.
Quantitative Real-Time PCR and Western-blot were used in detection of mRNA and protein expression. Lentivirus infection was used to overexpression or knock down target gene. Alarma blue assay was used to monitor cells proliferation. Flow cytometry analysis was performed to test protein expression and apoptosis level. Immunohistochemistry was used to identify protein expression in tissue. Statistical differences between two groups are evaluated by two-tailed t-tests. The comparison among multiple groups is performed by one-way Analysis of Variance (ANOVA) followed by Dunnett's posttest. The statistical significance of the Kaplan-Meier survival plot is determined by log-rank analysis.
MMP7 as one of the most up-regulated genes in T-DM1 resistant NCI-N87 gastric adenocarcinoma cells compared to matched naïve cell lines. T-DM1 resistant NCI-N87 cell lines by exposed to T-DM1 in vitro. Exogenous overexpression of MMP7 promotes T-DM1 resistance and tumor growth in NCI-N87 cell lines while MMP7 knockdown enhanced sensitivity to T-DM1 in T-DM1 resistant NCI-N87 cell lines established previously. MMP7 was enriched in high WHO grade GC samples and implies poor outcomes for these patients. DKK1 as one of the most correlated genes to MMP7 in gastric adenocarcinoma and knock-down of DKK1 or inhibition of Wnt/β-catenin pathway led to a decreased expression of MMP7 and resistance to T-DM1.
DKK1 and Wnt/β-catenin-dependent activation of MMP7 induces T-DM1 resistance and leads to the poor prognosis of gastric adenocarcinoma, which might be a novel potential therapeutical target for T-DM1 resistant gastric adenocarcinoma.
胃腺癌是最常见且致命的癌症类型之一，是亚洲成年人癌症相关死亡的第二大主要原因，基于病理学或分子生物学的早期诊断可能是改善胃腺癌患者治疗效果的最有效方法之一。
采用定量实时聚合酶链反应（qRT-PCR）和蛋白质免疫印迹法检测mRNA和蛋白质表达。利用慢病毒感染过表达或敲低靶基因。采用阿尔玛蓝检测法监测细胞增殖。进行流式细胞术分析以检测蛋白质表达和细胞凋亡水平。采用免疫组织化学法鉴定组织中的蛋白质表达。两组间的统计学差异采用双侧t检验进行评估。多组间的比较采用单因素方差分析（ANOVA），随后进行Dunnett事后检验。Kaplan-Meier生存曲线的统计学显著性通过对数秩分析确定。
与匹配的未处理细胞系相比，MMP7是曲妥珠单抗-美坦新偶联物（T-DM1）耐药的NCI-N87胃腺癌细胞中上调最明显的基因之一。通过体外暴露于T-DM1建立T-DM1耐药的NCI-N87细胞系。MMP7的外源性过表达促进NCI-N87细胞系对T-DM1的耐药性和肿瘤生长，而在先前建立的T-DM1耐药的NCI-N87细胞系中敲低MMP7可增强对T-DM1的敏感性。MMP7在世界卫生组织（WHO）高分级胃癌样本中富集，提示这些患者预后不良。DKK1是胃腺癌中与MMP7相关性最强的基因之一，敲低DKK1或抑制Wnt/β-连环蛋白信号通路可导致MMP7表达降低及对T-DM1耐药性下降。
DKK1和Wnt/β-连环蛋白依赖性激活MMP7诱导T-DM1耐药并导致胃腺癌预后不良，这可能是T-DM1耐药胃腺癌的一个新的潜在治疗靶点。
