目的研究Notch4受体激活后对慢性髓系白血病细胞株K562增殖的影响及可能的作用机制。方法用脂质体分别将携带Notch4胞内段(ICN4)的质粒pc DNA 3.1-ICN4及空载体质粒pc DNA 3.1转染入K562细胞,用G418筛选出稳定表达ICN4的细胞株。观察K56...目的研究Notch4受体激活后对慢性髓系白血病细胞株K562增殖的影响及可能的作用机制。方法用脂质体分别将携带Notch4胞内段(ICN4)的质粒pc DNA 3.1-ICN4及空载体质粒pc DNA 3.1转染入K562细胞,用G418筛选出稳定表达ICN4的细胞株。观察K562细胞ICN4转染后的形态变化,MTT法分析细胞增殖水平,RT-PCR法和Western blot法检测Notch4受体、Hes1、Hey1下游靶基因mRNA及蛋白的表达,流式细胞仪检测细胞周期分布。结果筛选出稳定表达ICN4的细胞株K562/ICN4细胞,与对照组及空载体组比较,ICN4转染组K562细胞数量减少,胞膜透亮度减小,核染色质固缩,核浆比例减低;ICN4转染后K562细胞生长受抑(P<0.05),且随时间延长而明显;Notch4受体及Hes1下游靶基因mRNA及蛋白表达水平相似,均较对照组及空载体组表达增强,但Hey1下游靶基因mRNA及蛋白表达水平未见明显变化;细胞周期检测结果示,转染48 h后细胞阻滞于G1期(P<0.05),S期细胞减少(P<0.05)。结论 Notch4受体激活可抑制K562细胞增殖,其机制可能是通过激活下游靶基因Hes1表达,而调控细胞于G1期而实现的。展开更多
BACKGROUND: Notch signaling is critical to physiologic angiogenesis and has been implicated in tumor angiogenesis and metastasis. Notch signaling was reported to exert either oncogenic or tumor-suppressive function in...BACKGROUND: Notch signaling is critical to physiologic angiogenesis and has been implicated in tumor angiogenesis and metastasis. Notch signaling was reported to exert either oncogenic or tumor-suppressive function in hepatocellular carcinoma (HCC) tumorigenesis. However, the prognostic significance of Notch receptors in HCC remains uncertain. In this study, we investigated the roles of Notch receptors in the prognosis of HCC. METHODS: We investigated the expressions of Notch receptors in tumor tissue microarrays of 288 patients with primary HCC who had undergone curative resection using immunohistochemistry. Additionally, prognostic factors of HCC were examined by univariate and multivariate analyses. The median follow-up period was 97.1 months. Tumor recurrence was detected in 189 patients (65.6%), and 99 (34.4%) died of HCC. RESULTS: Cytoplasmic expression of Notch1, cytoplasmic expression of Notch3, coexistent nuclear expression of Notch3, and cytoplasmic Notch4 overexpression were observed in 145 (50.3%), 60 (20.8%), 17 (5.9%), and 172 (59.7%) of the 288 HCCs, respectively. Multivariate analyses revealed that Notch1 expression (P=0.029), Edmondson grade Ⅲ (P=0.038), and higher BCLC stage (P【0.001) were independent predictors of shorter disease-free survival. Cytoplasmic Notch3 expression tended to be an independent predictor of shorter disease-free survival (P=0.055). Notch1 expression (P=0.039), Notch4 overexpression (P=0.012), and higher BCLC stage (P【0.001) were independent predictors of shorter disease-specific survival. On univariate analysis, Notch1 expression tended to show an unfavorable influence on disease-specific survival (P=0.063) and Notch4 overexpression did not show an unfavorable influence on disease-specific survival (P=0.103). CONCLUSIONS: Notch1 expression might be an independent predictor of both shorter disease-free survival and shorter disease-specific survival in HCC patients after curative resection. Notch4 overexpression might be an independent predictor of shorter disease-specific survival. Notch1 could be used as an immunohistochemical biomarker to detect patients with a high-risk of recurrence. Notch1 and Notch4 could be used as immunohistochemical biomarkers to detect patients with a shorter disease-specific survival.展开更多
文摘目的研究Notch4受体激活后对慢性髓系白血病细胞株K562增殖的影响及可能的作用机制。方法用脂质体分别将携带Notch4胞内段(ICN4)的质粒pc DNA 3.1-ICN4及空载体质粒pc DNA 3.1转染入K562细胞,用G418筛选出稳定表达ICN4的细胞株。观察K562细胞ICN4转染后的形态变化,MTT法分析细胞增殖水平,RT-PCR法和Western blot法检测Notch4受体、Hes1、Hey1下游靶基因mRNA及蛋白的表达,流式细胞仪检测细胞周期分布。结果筛选出稳定表达ICN4的细胞株K562/ICN4细胞,与对照组及空载体组比较,ICN4转染组K562细胞数量减少,胞膜透亮度减小,核染色质固缩,核浆比例减低;ICN4转染后K562细胞生长受抑(P<0.05),且随时间延长而明显;Notch4受体及Hes1下游靶基因mRNA及蛋白表达水平相似,均较对照组及空载体组表达增强,但Hey1下游靶基因mRNA及蛋白表达水平未见明显变化;细胞周期检测结果示,转染48 h后细胞阻滞于G1期(P<0.05),S期细胞减少(P<0.05)。结论 Notch4受体激活可抑制K562细胞增殖,其机制可能是通过激活下游靶基因Hes1表达,而调控细胞于G1期而实现的。
文摘BACKGROUND: Notch signaling is critical to physiologic angiogenesis and has been implicated in tumor angiogenesis and metastasis. Notch signaling was reported to exert either oncogenic or tumor-suppressive function in hepatocellular carcinoma (HCC) tumorigenesis. However, the prognostic significance of Notch receptors in HCC remains uncertain. In this study, we investigated the roles of Notch receptors in the prognosis of HCC. METHODS: We investigated the expressions of Notch receptors in tumor tissue microarrays of 288 patients with primary HCC who had undergone curative resection using immunohistochemistry. Additionally, prognostic factors of HCC were examined by univariate and multivariate analyses. The median follow-up period was 97.1 months. Tumor recurrence was detected in 189 patients (65.6%), and 99 (34.4%) died of HCC. RESULTS: Cytoplasmic expression of Notch1, cytoplasmic expression of Notch3, coexistent nuclear expression of Notch3, and cytoplasmic Notch4 overexpression were observed in 145 (50.3%), 60 (20.8%), 17 (5.9%), and 172 (59.7%) of the 288 HCCs, respectively. Multivariate analyses revealed that Notch1 expression (P=0.029), Edmondson grade Ⅲ (P=0.038), and higher BCLC stage (P【0.001) were independent predictors of shorter disease-free survival. Cytoplasmic Notch3 expression tended to be an independent predictor of shorter disease-free survival (P=0.055). Notch1 expression (P=0.039), Notch4 overexpression (P=0.012), and higher BCLC stage (P【0.001) were independent predictors of shorter disease-specific survival. On univariate analysis, Notch1 expression tended to show an unfavorable influence on disease-specific survival (P=0.063) and Notch4 overexpression did not show an unfavorable influence on disease-specific survival (P=0.103). CONCLUSIONS: Notch1 expression might be an independent predictor of both shorter disease-free survival and shorter disease-specific survival in HCC patients after curative resection. Notch4 overexpression might be an independent predictor of shorter disease-specific survival. Notch1 could be used as an immunohistochemical biomarker to detect patients with a high-risk of recurrence. Notch1 and Notch4 could be used as immunohistochemical biomarkers to detect patients with a shorter disease-specific survival.
