Radiofrequency ablation(RFA)is the most common approach to thermal ablation for cancer therapy.Unfortunately,its efficacy is limited by incomplete ablation,and further optimization of RFA is required.Here,we demonstra...Radiofrequency ablation(RFA)is the most common approach to thermal ablation for cancer therapy.Unfortunately,its efficacy is limited by incomplete ablation,and further optimization of RFA is required.Here,we demonstrate that incubation at 65°C triggers more EG7 tumor cell death by necrosis than treatment at 45°C,and the 65°C-treated cells are more effective at inducing antigen-specific CD8^(+)cytotoxic T lymphocyte(CTL)responses after injection in mice than the 45°C-treated ones.Dendritic cells(DCs)that phagocytose 65°C-treated EG7 cells become mature with upregulated MHCII and CD80 expression and are capable of efficiently inducing effector CTLs in mouse tumor models.RFA(65°C)therapy of EG7 tumors induces large areas of tumor necrosis and stimulates CTL responses.This leads to complete regression of small(~100 mm^(3))tumors but fails to suppress the growth of larger(~350 mm^(3))tumors.The administration of the Toll-like receptor-9(TLR9)agonist unmethylated cytosine-phosphorothioate-guanine oligonucleotide(CpG)to DCs phagocytosing 65°C-treated EG7 cells enhances the expression of MHCII and CD40 on DCs as well as DC-induced stimulation of CTL responses.Importantly,the intratumoral administration of CpG following RFA also increases the frequencies of tumor-associated immunogenic CD11b−CD11c^(+)CD103^(+)DC2 and CD11b+F4/80+MHCII+M1 macrophages and increases CD4^(+)and CD8^(+)T-cell tumor infiltration,leading to enhanced CD4^(+)T cell-dependent CTL responses and potent inhibition of primary RFA-treated or distant untreated tumor growth as well as tumor lung metastasis in mice bearing larger tumors.Overall,our data indicate that CpG administration,which enhances RFA-induced CTL responses and ultimately potentiates the inhibition of primary tumor growth and lung metastasis,is a promising strategy for improving RFA treatment,which may assist in optimizing this important cancer therapy.展开更多
Objective:Cancer stem cell is one of the important causes of tumorigenesis as well as a drug target in the treatment of malignant tumor.However,at present,there is no immune vaccine targeting these cells.Octamer-bindi...Objective:Cancer stem cell is one of the important causes of tumorigenesis as well as a drug target in the treatment of malignant tumor.However,at present,there is no immune vaccine targeting these cells.Octamer-binding transcription factor 4(OCT4),a marker of embryonic stem cells and germ cells,often highly expresses in the early stages of tumorigenesis and is therefore a good candidate for cancer vaccine development.Methods:To identify the optimal carrier and adjuvant combination,we chemically synthesized and linked three different OCT4 epitope antigens to a carrier protein,keyhole limpet hemocyanin(KLH),combined with Toll-like receptor 9 agonist(TLR9).Results:Immunization with OCT4-3+TLR9 produced the strongest immune response in mice.In prevention assays,significant tumor growth inhibition was achieved in BABL/c mice treated with OCT4-3+TLR9(P<0.01).Importantly,the results showed that cytotoxic T lymphocyte activity and the inhibition of tumor growth were enhanced in mice immunized with OCT4-3 combined with TLR9.Meanwhile,multiple cytokines[such as interferon(IFN)-γ(P<0.05),interleukin(IL)-12(P<0.05),IL-2(P<0.01),and IL-6(P<0.05)]promoting cellular immune responses were shown to be greatly enhanced in mice immunized with OCT4-3+TLR9.Moreover,we considered safety considerations in terms of the composition of the vaccines to help facilitate the development of effective next-generation vaccines.Conclusions:Collectively,these experiments demonstrated that combination therapy with TLR9 agonist induced a tumor-specific adaptive immune response,leading to the suppression of primary tumor growth in testis embryonic carcinoma.展开更多
基金supported by grants from CoMRAD(#417578)College of Medicine,University of Saskatchewan,Prostate Cancer Fight Foundation(#417782)+1 种基金Royal University Hospital Research Foundation(#417450)Saskatchewan Health Research Foundation(#418672).
文摘Radiofrequency ablation(RFA)is the most common approach to thermal ablation for cancer therapy.Unfortunately,its efficacy is limited by incomplete ablation,and further optimization of RFA is required.Here,we demonstrate that incubation at 65°C triggers more EG7 tumor cell death by necrosis than treatment at 45°C,and the 65°C-treated cells are more effective at inducing antigen-specific CD8^(+)cytotoxic T lymphocyte(CTL)responses after injection in mice than the 45°C-treated ones.Dendritic cells(DCs)that phagocytose 65°C-treated EG7 cells become mature with upregulated MHCII and CD80 expression and are capable of efficiently inducing effector CTLs in mouse tumor models.RFA(65°C)therapy of EG7 tumors induces large areas of tumor necrosis and stimulates CTL responses.This leads to complete regression of small(~100 mm^(3))tumors but fails to suppress the growth of larger(~350 mm^(3))tumors.The administration of the Toll-like receptor-9(TLR9)agonist unmethylated cytosine-phosphorothioate-guanine oligonucleotide(CpG)to DCs phagocytosing 65°C-treated EG7 cells enhances the expression of MHCII and CD40 on DCs as well as DC-induced stimulation of CTL responses.Importantly,the intratumoral administration of CpG following RFA also increases the frequencies of tumor-associated immunogenic CD11b−CD11c^(+)CD103^(+)DC2 and CD11b+F4/80+MHCII+M1 macrophages and increases CD4^(+)and CD8^(+)T-cell tumor infiltration,leading to enhanced CD4^(+)T cell-dependent CTL responses and potent inhibition of primary RFA-treated or distant untreated tumor growth as well as tumor lung metastasis in mice bearing larger tumors.Overall,our data indicate that CpG administration,which enhances RFA-induced CTL responses and ultimately potentiates the inhibition of primary tumor growth and lung metastasis,is a promising strategy for improving RFA treatment,which may assist in optimizing this important cancer therapy.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.81803081,81703050,and 21677102)Shenzhen Basic Research Project(Grant Nos.JCYJ20170303160906960,JCYJ20170307100703967,and JCYJ20160331114230843)+2 种基金the Shenzhen International Cooperation Research Project(Grant No.GJHZ20170313111237888)the Subject Layout Project of Shenzhen Science and Technology Creation Commission(Grant Nos.JCYJ20170818092553608 and JCYJ20160331114230843)the China Shenzhen Peacock Innovation Team Project(Grant No.KQTD20140630100658078)。
文摘Objective:Cancer stem cell is one of the important causes of tumorigenesis as well as a drug target in the treatment of malignant tumor.However,at present,there is no immune vaccine targeting these cells.Octamer-binding transcription factor 4(OCT4),a marker of embryonic stem cells and germ cells,often highly expresses in the early stages of tumorigenesis and is therefore a good candidate for cancer vaccine development.Methods:To identify the optimal carrier and adjuvant combination,we chemically synthesized and linked three different OCT4 epitope antigens to a carrier protein,keyhole limpet hemocyanin(KLH),combined with Toll-like receptor 9 agonist(TLR9).Results:Immunization with OCT4-3+TLR9 produced the strongest immune response in mice.In prevention assays,significant tumor growth inhibition was achieved in BABL/c mice treated with OCT4-3+TLR9(P<0.01).Importantly,the results showed that cytotoxic T lymphocyte activity and the inhibition of tumor growth were enhanced in mice immunized with OCT4-3 combined with TLR9.Meanwhile,multiple cytokines[such as interferon(IFN)-γ(P<0.05),interleukin(IL)-12(P<0.05),IL-2(P<0.01),and IL-6(P<0.05)]promoting cellular immune responses were shown to be greatly enhanced in mice immunized with OCT4-3+TLR9.Moreover,we considered safety considerations in terms of the composition of the vaccines to help facilitate the development of effective next-generation vaccines.Conclusions:Collectively,these experiments demonstrated that combination therapy with TLR9 agonist induced a tumor-specific adaptive immune response,leading to the suppression of primary tumor growth in testis embryonic carcinoma.