The peptides mixture was prepared from tumor cells by freezing-thawing cells, precipitation by heating, followed by acidification of the solution. The activation and proliferation of mouse splenocytes by HSP70-peptide...The peptides mixture was prepared from tumor cells by freezing-thawing cells, precipitation by heating, followed by acidification of the solution. The activation and proliferation of mouse splenocytes by HSP70-peptide complex, formed by the binding of HSP70 and peptides in vitro, were observed, so was the specific cytotoxicity of the proliferative lymphocytes to tumor cells. The phenotypes of the proliferative lymphocytes were analyzed by a flow cytometer. BALB/c mice inoculated with H22 hepatocarcinoma cells in peritoneal cavity or hind thigh were immunized by injection with HSP70-peptides complex to observe the inhibitory effect of the immunization on tumor and lifetime of tumor-bearing mice. On the other hand, blood samples were collected from the immunized mice to check the functions of liver and kidney. The results showed that the peptides mixture from tumor cells contained tumor-specific antigen peptides which could be presented by HSP70 to activate lymphocytes in vitro, the proliferative lymphocytes were T cells which were specifically cytotoxic to tumor cells, the in vivo growth of both ascitic and solid carcinoma could be suppressed by immunization with HSP70-peptides and the lifetime of tumor-bearing mice was prolonged, the in vivo immunization with HSP70-H22-peptides had no impact on the function of mouse liver and kidney, suggesting that there was no occurrence of autoimmunity in vivo after immunization.展开更多
Regulatory T cells （Tregs） expressing forkhead/winged-helix transcription factor Foxp3 represent a distinct lineage of lymphocytes which play a central role in protecting the host from autoimmune diseases. However, ...Regulatory T cells （Tregs） expressing forkhead/winged-helix transcription factor Foxp3 represent a distinct lineage of lymphocytes which play a central role in protecting the host from autoimmune diseases. However, Tregs also pose a major problem to anti-tumor immunity. Growing body of evidence from both laboratory and clinical investigations has demonstrated that expansion and accumulation of these immunosuppressive cells correlates with advanced tumor growth and predicts poor disease prognosis. How tumor development subverts normal self-tolerance function of Tregs thereby thwarts host anti-tumor immunity remains elusive. This review will discuss our current knowledge in understanding the dynamics and plasticity of Foxp3~ Treg activation and induction in tumor bearing hosts and their interaction with various antigen presenting cells （APCs） in tumor microenvironment leading to the establishment of active local and systemic immune suppression. Cellular ＆ Molecular Immunology.展开更多
以程序性死亡配体1/程序性死亡受体1(programmed cell death ligand 1/programmed cell death protein 1,PD-L1/PD-1)免疫检查点阻断治疗为代表的肿瘤免疫疗法在临床上取得了令人鼓舞的治疗效果。小分子肿瘤免疫治疗药物与免疫检查点抗...以程序性死亡配体1/程序性死亡受体1(programmed cell death ligand 1/programmed cell death protein 1,PD-L1/PD-1)免疫检查点阻断治疗为代表的肿瘤免疫疗法在临床上取得了令人鼓舞的治疗效果。小分子肿瘤免疫治疗药物与免疫检查点抗体药物的联用,为肿瘤治疗提供了新策略。因此,研发能阻断PD-L1/PD-1免疫检查点相互作用的小分子药物是下一代肿瘤免疫疗法的新方向。本研究对丹酚酸B(salvianolic acid B,SAB)下调肿瘤细胞中PD-L1表达发挥抗肿瘤作用及机制进行了研究。利用Western blot、流式细胞术、PD-1/PD-L1相互作用分析SAB对结肠癌细胞RKO和前列腺癌细胞PC3细胞内和膜表面PD-L1蛋白表达水平的影响;荧光定量PCR检测SAB对PD-L1 mRNA的影响;细胞阻抗法和结晶紫法检测SAB对人类外周血单核细胞(peripheral blood mononuclear cell,PBMC)杀伤肿瘤细胞的效果;表面等离子共振技术分析SAB与泛素羧基末端水解酶2(ubiquitin carboxyl-terminal hydrolase 2,USP2)的直接相互作用;MC38荷瘤小鼠(所有动物实验均遵循中国医学科学院医药生物技术研究所伦理委员会的规定)检测SAB的体内抑瘤效果。结果表明,SAB能分别以浓度依赖性和时间依赖性方式下调RKO、PC3细胞中以及细胞膜表面PD-L1的水平,这与SAB抑制肿瘤细胞中去泛素化酶USP2的活性有关。机制研究发现,SAB可与USP2发生直接相互作用并抑制其去泛素化酶活性,从而促进PD-L1发生泛素-蛋白酶体途径降解。此外,SAB可促进共培养的PBMC对RKO细胞的杀伤作用。小鼠荷瘤实验证实,SAB可显著抑制C57BL/6小鼠中MC38移植瘤的生长。20 mg·kg^(-1) SAB处理荷瘤小鼠后,可使瘤体积减少63.2%。以上结果说明,SAB通过直接结合USP2并抑制其活性,促进PD-L1发生泛素-蛋白酶体途径降解,从而发挥抗肿瘤作用。本研究为将SAB研发成靶向USP2-PD-L1轴的小分子肿瘤免疫治疗药物奠定了基础。展开更多
BACKGROUND: Radiofrequency ablation (RFA) is a minimally invasive surgical procedure which has widespread popularity in the treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA stimulates...BACKGROUND: Radiofrequency ablation (RFA) is a minimally invasive surgical procedure which has widespread popularity in the treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA stimulates anti-tumor immunity, possibly through the induction heat shock protein 70 (HSP70) expression. HSP70 has the capacity to affect the immunogenicity of tumor cells, to chaperone antigenic peptides and deliver these into antigen presentation pathways within antigen-presenting cells, and to activate and regulate innate and adaptive immunity, which makes it useful in immunotherapeutic strategies for the treatment of cancers. DATA SOURCES: An English-language literature search was conducted using MEDLINE (1991-2010) on anti-tumor immunity, heat shock protein 70, radiofrequency ablation, hepatic cancer, pancreatic cancer, and other related subjects. RESULTS: RFA has an increasing application in the surgical treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA can induce the expression of HSP70 which possesses properties that enable it to influence a variety of immunological processes. Tumor-derived HSP70 is regarded as a potent adjuvant facilitating presentation of tumor antigens and induction of anti-tumor immunity. CONCLUSIONS: This review addresses the potential association of RFA, HSP70, and anti-tumor immunity in treatment of hepatic and pancreatic cancers. To establish direct evidence of a potential association of RFA, HSP70, and anti-tumor immunity in hepatic and pancreatic cancers, further investigations should be conducted.展开更多
In recent decades, accumulating evidence from both animal and clinical studies has suggested that a sufficiently activated immune system may strongly augment various types of cancer treatment, including photodynamic t...In recent decades, accumulating evidence from both animal and clinical studies has suggested that a sufficiently activated immune system may strongly augment various types of cancer treatment, including photodynamic therapy （PDT）. Through the generation of reactive oxygen species, PDT eradicates tumors by triggering localized tumor damage and inducing anti-tumor immunity. As the major component of anti-tumor immunity, the involvement of a cell-mediated immune response in PDT has been well investigated in the past decade, whereas the role of humoral immunity has remained relatively unexplored. In the present investigation, using the photosensitizer BAM-SiPc and the CT26 tumor-bearing BALB/c mouse model, it was demonstrated that both cell-mediated and humoral adaptive immune components could be involved in PDT. With a vascular PDT （VPDT） regimen, BAM-SiPc could eradicate the tumors of -70% of tumor-bearing mice and trigger an anti-tumor immune response that could last for more than 1 year. An elevation of Th2 cytokines was detected ex vivoafter VPDT, indicating the potential involvement of a humoral response. An analysis of serum from the VPDT-cured mice also revealed elevated levels of tumor-specific antibodies. Moreover, this serum could effectively hinder tumor growth and protect the mice against further re-challenge in a T-cell-dependent manner. Taken together, these results show that the humoral components induced after BAM-SiPc-VPDT could assist the development of anti-tumor immunity.展开更多
基金This work was supported by the National Natural Science Foundation of China (Grant No.39970322) Trans-Century Training Programme Foundation for Talent under the supervision of Ministry of Education of China.
文摘The peptides mixture was prepared from tumor cells by freezing-thawing cells, precipitation by heating, followed by acidification of the solution. The activation and proliferation of mouse splenocytes by HSP70-peptide complex, formed by the binding of HSP70 and peptides in vitro, were observed, so was the specific cytotoxicity of the proliferative lymphocytes to tumor cells. The phenotypes of the proliferative lymphocytes were analyzed by a flow cytometer. BALB/c mice inoculated with H22 hepatocarcinoma cells in peritoneal cavity or hind thigh were immunized by injection with HSP70-peptides complex to observe the inhibitory effect of the immunization on tumor and lifetime of tumor-bearing mice. On the other hand, blood samples were collected from the immunized mice to check the functions of liver and kidney. The results showed that the peptides mixture from tumor cells contained tumor-specific antigen peptides which could be presented by HSP70 to activate lymphocytes in vitro, the proliferative lymphocytes were T cells which were specifically cytotoxic to tumor cells, the in vivo growth of both ascitic and solid carcinoma could be suppressed by immunization with HSP70-peptides and the lifetime of tumor-bearing mice was prolonged, the in vivo immunization with HSP70-H22-peptides had no impact on the function of mouse liver and kidney, suggesting that there was no occurrence of autoimmunity in vivo after immunization.
基金This study was in part supported by cancer endowment fund of MDACC and grants from NIH.
文摘Regulatory T cells （Tregs） expressing forkhead/winged-helix transcription factor Foxp3 represent a distinct lineage of lymphocytes which play a central role in protecting the host from autoimmune diseases. However, Tregs also pose a major problem to anti-tumor immunity. Growing body of evidence from both laboratory and clinical investigations has demonstrated that expansion and accumulation of these immunosuppressive cells correlates with advanced tumor growth and predicts poor disease prognosis. How tumor development subverts normal self-tolerance function of Tregs thereby thwarts host anti-tumor immunity remains elusive. This review will discuss our current knowledge in understanding the dynamics and plasticity of Foxp3~ Treg activation and induction in tumor bearing hosts and their interaction with various antigen presenting cells （APCs） in tumor microenvironment leading to the establishment of active local and systemic immune suppression. Cellular ＆ Molecular Immunology.
基金supported by grants from the State Key Development Program for Basic Research of China (973 Program)(2009CB521704)the National High Technology Research and Development Program of China (863 Program) (2006AA02A245)
文摘BACKGROUND: Radiofrequency ablation (RFA) is a minimally invasive surgical procedure which has widespread popularity in the treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA stimulates anti-tumor immunity, possibly through the induction heat shock protein 70 (HSP70) expression. HSP70 has the capacity to affect the immunogenicity of tumor cells, to chaperone antigenic peptides and deliver these into antigen presentation pathways within antigen-presenting cells, and to activate and regulate innate and adaptive immunity, which makes it useful in immunotherapeutic strategies for the treatment of cancers. DATA SOURCES: An English-language literature search was conducted using MEDLINE (1991-2010) on anti-tumor immunity, heat shock protein 70, radiofrequency ablation, hepatic cancer, pancreatic cancer, and other related subjects. RESULTS: RFA has an increasing application in the surgical treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA can induce the expression of HSP70 which possesses properties that enable it to influence a variety of immunological processes. Tumor-derived HSP70 is regarded as a potent adjuvant facilitating presentation of tumor antigens and induction of anti-tumor immunity. CONCLUSIONS: This review addresses the potential association of RFA, HSP70, and anti-tumor immunity in treatment of hepatic and pancreatic cancers. To establish direct evidence of a potential association of RFA, HSP70, and anti-tumor immunity in hepatic and pancreatic cancers, further investigations should be conducted.
文摘In recent decades, accumulating evidence from both animal and clinical studies has suggested that a sufficiently activated immune system may strongly augment various types of cancer treatment, including photodynamic therapy （PDT）. Through the generation of reactive oxygen species, PDT eradicates tumors by triggering localized tumor damage and inducing anti-tumor immunity. As the major component of anti-tumor immunity, the involvement of a cell-mediated immune response in PDT has been well investigated in the past decade, whereas the role of humoral immunity has remained relatively unexplored. In the present investigation, using the photosensitizer BAM-SiPc and the CT26 tumor-bearing BALB/c mouse model, it was demonstrated that both cell-mediated and humoral adaptive immune components could be involved in PDT. With a vascular PDT （VPDT） regimen, BAM-SiPc could eradicate the tumors of -70% of tumor-bearing mice and trigger an anti-tumor immune response that could last for more than 1 year. An elevation of Th2 cytokines was detected ex vivoafter VPDT, indicating the potential involvement of a humoral response. An analysis of serum from the VPDT-cured mice also revealed elevated levels of tumor-specific antibodies. Moreover, this serum could effectively hinder tumor growth and protect the mice against further re-challenge in a T-cell-dependent manner. Taken together, these results show that the humoral components induced after BAM-SiPc-VPDT could assist the development of anti-tumor immunity.
