AIM: To investigate whether the transactivator of the proglucagon gene (Gcg), Cdx-2, synergizes with other transcription factors in stimulating Gcg expression and the trans-differentiation of Gcg-expressing cells. MET...AIM: To investigate whether the transactivator of the proglucagon gene (Gcg), Cdx-2, synergizes with other transcription factors in stimulating Gcg expression and the trans-differentiation of Gcg-expressing cells. METHODS: We conducted affinity chromatography to identify proteins that interact with Cdx-2, using GST-tagged Cdx-2 against cell lysates from pancreatic InR1-G9 and intestinal GLUTag cell lines. This was followed by a mass-spectrometry analysis. From a potential Cdx-2 interaction protein identified, we examined its expression in pancreatic and gut endocrine cells, confirmed its interaction with Cdx-2 by GST-pull down and determined its effect in provoking Gcg expression in cell lines that do not express endogenous Gcg.RESULTS: We identified 18 potential Cdx-2 interacting proteins. One of them is Nkx6.2. This homeodomain (HD) protein is expressed in pancreatic α and intestinal endocrine L cells but not in insulin producing cell lines, inclu ding In111. Nkx6.2, but not Nkx6.1, was shown to intera ct with Cdx-2, detected by GST-pull down. Furthermore, Nkx6.2 was found to synergize with Cdx-2 in provoking Gcg expression when they were ectopically expressed in the In111 cell line. Finally, when Cdx-2 and Nkx6.2 were co-transfected into the undifferentiated rat intestinal IEC-6 cell line, it produced detectable amount of Gcg mRNA. CONCLUSION: Cdx-2 recruits Nkx6.2 in exerting its ef fect in stimulating Gcg expression. Our observations fur ther support the notion that multiple HD proteins, including Cdx-2 and Nkx6.2, are involved in the regulation of Gcg expression and the genesis of Gcg-producing cells.展开更多
目的:探讨CDX-2、NKD1、GDF11在大肠癌中的表达及其与预后的相关性分析。方法:选取2016年1月~2019年6月的大肠癌患者284例作为研究对象,采用免疫组织化学法(SP)检测大肠癌组织及其癌旁正常组织中的CDX-2、NKD1、GDF11表达,分析其在大肠...目的:探讨CDX-2、NKD1、GDF11在大肠癌中的表达及其与预后的相关性分析。方法:选取2016年1月~2019年6月的大肠癌患者284例作为研究对象,采用免疫组织化学法(SP)检测大肠癌组织及其癌旁正常组织中的CDX-2、NKD1、GDF11表达,分析其在大肠癌患者的临床病理特征及预后的相关性。结果:大肠癌组织的GDF11阳性表达率显著高于癌旁正常组织,CDX-2和NKD1阳性表达率显著低于癌旁正常组织;CDX-2、NKD1和GDF11阳性表达与肿瘤阶段、淋巴结受累、同步转移、组织学分级、CEA水平有关;CDX-2阳性表达患者3年生存率显著高于其阴性表达患者(80.23% vs 53.03%),NKD1阳性表达患者3年生存率显著高于其阴性表达患者(78.95% vs 54.81%),GDF11阳性表达患者3年生存率显著低于其阴性表达患者(57.33% vs 76.27%);CDX-2的表达和NKD1表达相关较强,GDF11与CDX-2、NKD1的表达率相关性较弱。结论:CDX-2和NKD1可能协同参与了降低肿瘤细胞的入侵和迁移、抑制癌组织的增殖过程,GDF11作为生长调节因子可调节癌细胞增殖和分化,均可作为预后的重要指示。展开更多
基金Supported by the Grants from the Canadian Institute of Health Research (CIHR, MOP36398)Canadian Diabetes Association (1198) to Tianru Jin
文摘AIM: To investigate whether the transactivator of the proglucagon gene (Gcg), Cdx-2, synergizes with other transcription factors in stimulating Gcg expression and the trans-differentiation of Gcg-expressing cells. METHODS: We conducted affinity chromatography to identify proteins that interact with Cdx-2, using GST-tagged Cdx-2 against cell lysates from pancreatic InR1-G9 and intestinal GLUTag cell lines. This was followed by a mass-spectrometry analysis. From a potential Cdx-2 interaction protein identified, we examined its expression in pancreatic and gut endocrine cells, confirmed its interaction with Cdx-2 by GST-pull down and determined its effect in provoking Gcg expression in cell lines that do not express endogenous Gcg.RESULTS: We identified 18 potential Cdx-2 interacting proteins. One of them is Nkx6.2. This homeodomain (HD) protein is expressed in pancreatic α and intestinal endocrine L cells but not in insulin producing cell lines, inclu ding In111. Nkx6.2, but not Nkx6.1, was shown to intera ct with Cdx-2, detected by GST-pull down. Furthermore, Nkx6.2 was found to synergize with Cdx-2 in provoking Gcg expression when they were ectopically expressed in the In111 cell line. Finally, when Cdx-2 and Nkx6.2 were co-transfected into the undifferentiated rat intestinal IEC-6 cell line, it produced detectable amount of Gcg mRNA. CONCLUSION: Cdx-2 recruits Nkx6.2 in exerting its ef fect in stimulating Gcg expression. Our observations fur ther support the notion that multiple HD proteins, including Cdx-2 and Nkx6.2, are involved in the regulation of Gcg expression and the genesis of Gcg-producing cells.
文摘目的:探讨CDX-2、NKD1、GDF11在大肠癌中的表达及其与预后的相关性分析。方法:选取2016年1月~2019年6月的大肠癌患者284例作为研究对象,采用免疫组织化学法(SP)检测大肠癌组织及其癌旁正常组织中的CDX-2、NKD1、GDF11表达,分析其在大肠癌患者的临床病理特征及预后的相关性。结果:大肠癌组织的GDF11阳性表达率显著高于癌旁正常组织,CDX-2和NKD1阳性表达率显著低于癌旁正常组织;CDX-2、NKD1和GDF11阳性表达与肿瘤阶段、淋巴结受累、同步转移、组织学分级、CEA水平有关;CDX-2阳性表达患者3年生存率显著高于其阴性表达患者(80.23% vs 53.03%),NKD1阳性表达患者3年生存率显著高于其阴性表达患者(78.95% vs 54.81%),GDF11阳性表达患者3年生存率显著低于其阴性表达患者(57.33% vs 76.27%);CDX-2的表达和NKD1表达相关较强,GDF11与CDX-2、NKD1的表达率相关性较弱。结论:CDX-2和NKD1可能协同参与了降低肿瘤细胞的入侵和迁移、抑制癌组织的增殖过程,GDF11作为生长调节因子可调节癌细胞增殖和分化,均可作为预后的重要指示。
