Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohisto...Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exon1. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2’-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the func-tional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony for-mation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colo-rectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.展开更多
基金Project (Nos. 30200333 and 30570840) supported by the NationalNatural Science Foundation of China
文摘Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exon1. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2’-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the func-tional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony for-mation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colo-rectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.
文摘急性肾损伤(acute kidney injury,AKI)是一种常见的术后并发症,尚无确切的生物标志物。金属蛋白酶2组织抑制剂(tissue inhibitor of metalloproteinases-2,TIMP-2)和胰岛素样生长因子结合蛋7(insulin-like growth factor-binding protein 7,IGFBP7)属于细胞周期阻滞生物标志物。近年众多临床研究发现尿液中TIMP-2联合IGFBP7的含量可较好地预测中重度AKI。2014年美国食品和药物管理局批准上市了"NephroCheck?"(尿[TIMP-2]×[IGFBP7]的检测)。本文将综述尿液中细胞周期阻滞生物标志物[TIMP-2]×[IGFBP7]的含量对手术后AKI风险预测的研究。
