Objective: Cancer immunotherapy has made remarkable advances in recent years, but its effectiveness in treating gastric cancer is often limited by the complexity of the tumor microenvironment and the lack of effective...Objective: Cancer immunotherapy has made remarkable advances in recent years, but its effectiveness in treating gastric cancer is often limited by the complexity of the tumor microenvironment and the lack of effective biomarkers. This study aimed to identify effective biomarkers for immunotherapy treatment by characterizing the tumor microenvironment.Methods: We retrieved the RNA-seq data from gastric cancer patients treated with the programmed death 1(PD-1) blockade pembrolizumab. Differentially expressed genes associated with clinical outcomes were identified and further analyzed using gene ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis. Gene signature scores were calculated by single sample Gene Set Enrichment Analysis(ssGSEA). The infiltration levels of immune cells were quantified using the xCell website. Cell type enrichment analysis was performed to compare treatment response and non-response groups, and regression analysis was used to investigate the relationship between interferon gamma(IFNγ) immune response and immune cell infiltration. Biomarkers were identified using least absolute shrinkage and selection operator(LASSO) analysis.Results: Compared to normal tissues, cytokine activity and interleukin-6 production were highly activated in gastric tumors. Responders to pembrolizumab showed significantly up-regulated expression of IFNγ responserelated genes. Cell type enrichment analysis revealed that Th1 cells were significantly enriched in the tumor microenvironment of responders. Regression analysis indicated that Th1 cells induced IFNγ response more efficiently than other cell types. Using signatures of Th1 cells, stromal cells and IFNγ response, a set of eight genes were identified that effectively predicted the efficacy of immunotherapy treatment and patient prognosis.Conclusions: Th1 cells promote therapeutic efficacy of PD-1 blockade by promoting IFNγ immune response in gastric cancer. The identified biomarkers have the potential to improve the effectiveness of immunotherapy treatment for gastric cancer patients.展开更多
目的 :克隆小鼠内皮抑素 (m Endostatin)编码区 c DNA序列并构建含 Egr- 1启动子的 IFNγ和 m Endo-statin双基因表达载体。方法 :利用逆转录多聚酶链反应法 (RT- PCR) ,以小鼠肝细胞 m RNA为模板 ,扩增获得全长 m Endostatin,与 p MD1...目的 :克隆小鼠内皮抑素 (m Endostatin)编码区 c DNA序列并构建含 Egr- 1启动子的 IFNγ和 m Endo-statin双基因表达载体。方法 :利用逆转录多聚酶链反应法 (RT- PCR) ,以小鼠肝细胞 m RNA为模板 ,扩增获得全长 m Endostatin,与 p MD1 8T载体连接作全自动测序 ,并利用基因重组技术构建含 Egr- 1启动子的 IFNγ和m Endostatin双基因表达质粒。结果 :经测序证实获得的 m Endostatin序列与文献报道完全一致 ,并构建了含 Egr-1启动子的 IFNγ和 m Endostatin双基因表达质粒 p Egr- IFNγ- m Endostatin。结论 :利用 RT- PCR法成功克隆了m Endostatin的 c DNA序列 ,构建了 p Egr- IFNγ- m Endostatin重组双基因表达质粒。展开更多
为提高工程菌-毕赤酵母X4诱导表达HBscFv-IFNγ(抗乙肝病毒表面抗原单链抗体-γ干扰素,single-chain Fv against HBVsurface antigen-γ-interferon)的量,本实验通过单因素和正交实验来优化发酵工艺,确定了X4表达HBscFv-IFNγ的最优工...为提高工程菌-毕赤酵母X4诱导表达HBscFv-IFNγ(抗乙肝病毒表面抗原单链抗体-γ干扰素,single-chain Fv against HBVsurface antigen-γ-interferon)的量,本实验通过单因素和正交实验来优化发酵工艺,确定了X4表达HBscFv-IFNγ的最优工艺条件:150mL摇瓶培养84h,甲醇添加量2.2%(v/v),接种后的OD600=6.5,装液量20mL。使HBscFv-IFNγ的产量由起始的15mg/L提高到21.14mg/L,提高达40.9%。这为进一步对HBscFv-IFNγ的纯化、药效研究和高密度培养奠定了基础。展开更多
基金financially supported by the National Natural Science Foundation of China (No. 82030079, 82341005, 81972656 and 82173035)the National Science and Technology Major Project of China (No. 2022YFC3400 901)Sino-Russian Math Center in PKU。
文摘Objective: Cancer immunotherapy has made remarkable advances in recent years, but its effectiveness in treating gastric cancer is often limited by the complexity of the tumor microenvironment and the lack of effective biomarkers. This study aimed to identify effective biomarkers for immunotherapy treatment by characterizing the tumor microenvironment.Methods: We retrieved the RNA-seq data from gastric cancer patients treated with the programmed death 1(PD-1) blockade pembrolizumab. Differentially expressed genes associated with clinical outcomes were identified and further analyzed using gene ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis. Gene signature scores were calculated by single sample Gene Set Enrichment Analysis(ssGSEA). The infiltration levels of immune cells were quantified using the xCell website. Cell type enrichment analysis was performed to compare treatment response and non-response groups, and regression analysis was used to investigate the relationship between interferon gamma(IFNγ) immune response and immune cell infiltration. Biomarkers were identified using least absolute shrinkage and selection operator(LASSO) analysis.Results: Compared to normal tissues, cytokine activity and interleukin-6 production were highly activated in gastric tumors. Responders to pembrolizumab showed significantly up-regulated expression of IFNγ responserelated genes. Cell type enrichment analysis revealed that Th1 cells were significantly enriched in the tumor microenvironment of responders. Regression analysis indicated that Th1 cells induced IFNγ response more efficiently than other cell types. Using signatures of Th1 cells, stromal cells and IFNγ response, a set of eight genes were identified that effectively predicted the efficacy of immunotherapy treatment and patient prognosis.Conclusions: Th1 cells promote therapeutic efficacy of PD-1 blockade by promoting IFNγ immune response in gastric cancer. The identified biomarkers have the potential to improve the effectiveness of immunotherapy treatment for gastric cancer patients.
文摘目的 :克隆小鼠内皮抑素 (m Endostatin)编码区 c DNA序列并构建含 Egr- 1启动子的 IFNγ和 m Endo-statin双基因表达载体。方法 :利用逆转录多聚酶链反应法 (RT- PCR) ,以小鼠肝细胞 m RNA为模板 ,扩增获得全长 m Endostatin,与 p MD1 8T载体连接作全自动测序 ,并利用基因重组技术构建含 Egr- 1启动子的 IFNγ和m Endostatin双基因表达质粒。结果 :经测序证实获得的 m Endostatin序列与文献报道完全一致 ,并构建了含 Egr-1启动子的 IFNγ和 m Endostatin双基因表达质粒 p Egr- IFNγ- m Endostatin。结论 :利用 RT- PCR法成功克隆了m Endostatin的 c DNA序列 ,构建了 p Egr- IFNγ- m Endostatin重组双基因表达质粒。
文摘为提高工程菌-毕赤酵母X4诱导表达HBscFv-IFNγ(抗乙肝病毒表面抗原单链抗体-γ干扰素,single-chain Fv against HBVsurface antigen-γ-interferon)的量,本实验通过单因素和正交实验来优化发酵工艺,确定了X4表达HBscFv-IFNγ的最优工艺条件:150mL摇瓶培养84h,甲醇添加量2.2%(v/v),接种后的OD600=6.5,装液量20mL。使HBscFv-IFNγ的产量由起始的15mg/L提高到21.14mg/L,提高达40.9%。这为进一步对HBscFv-IFNγ的纯化、药效研究和高密度培养奠定了基础。
