Research progress of CAR-T immunotherapy in solid tumors combined with new strategies / 中国药科大学学报

@#In recent years, the chimeric antigen receptor T-cell (CAR-T) therapy has achieved breakthrough progress in the treatment of hematologic malignancies. However, when it comes to solid tumors, numerous challenges persist.These include limited CAR-T cell infiltration, susceptibility to T cell exhaustion, off-target effects, and more.Thus, novel therapeutic strategies are imperative to enhance the efficacy of CAR-T therapy for solid tumors. In comparison to standalone CAR-T approaches, the combination of CAR-T with other tumor treatment modalities has demonstrated remarkable effectiveness in both preclinical and clinical research.This review article summarizes the advancements in combining CAR-T with various solid tumor treatments: antibody drugs, oncolytic viruses, tumor vaccines, and nanomedicines.The objective is to furnish a theoretical foundation and novel perspectives for the development of innovative CAR-T combination strategies tailored for solid tumor therapy.

Frontier and Future of Immunotherapy for Pancreatic Cancer / 肿瘤防治研究

Pancreatic cancer remains as one of the most lethal malignancies. Resistance to conventional therapies has led to little improvement in the survival of pancreatic cancer patients over the past few decades. Immune-based treatment strategies for pancreatic cancer, such as immune-checkpoint inhibitors, therapeutic vaccines, and combination immunotherapies show promise. Many immunotherapies have been explored in clinical trials, but they have yet to show significant therapeutic effects. Nevertheless, immunotherapy is inevitably the future of pancreatic cancer cure. This article introduces the current research progress and bottlenecks of immunotherapy for pancreatic cancer and puts forward further optimization directions and solutions. We hope to provide a reference for the future use of immunotherapy for pancreatic cancer.

mRNA cancer vaccines: Advances, trends and challenges

Patients exhibit good tolerance to messenger ribonucleic acid (mRNA) vaccines, and the choice of encoded molecules is flexible and diverse. These vaccines can be engineered to express full-length antigens containing multiple epitopes without major histocompatibility complex (MHC) restriction, are relatively easy to control and can be rapidly mass produced. In 2021, the U.S. Food and Drug Administration (FDA) approved the first mRNA-based coronavirus disease 2019 (COVID-19) vaccine produced by Pfizer and BioNTech, which has generated enthusiasm for mRNA vaccine research and development. Based on the above characteristics and the development of mRNA vaccines, mRNA cancer vaccines have become a research hotspot and have undergone rapid development, especially in the last five years. This review analyzes the advances in mRNA cancer vaccines from various perspectives, including the selection and expression of antigens/targets, the application of vectors and adjuvants, different administration routes, and preclinical evaluation, to reflect the trends and challenges associated with these vaccines.

Genetically-engineered "all-in-one" vaccine platform for cancer immunotherapy

An essential step for cancer vaccination is to break the immunosuppression and elicit a tumor-specific immunity. A major hurdle against cancer therapeutic vaccination is the insufficient immune stimulation of the cancer vaccines and lack of a safe and efficient adjuvant for human use. We discovered a novel cancer immunostimulant, trichosanthin (TCS), that is a clinically used protein drug in China, and developed a well-adaptable protein-engineering method for making recombinant protein vaccines by fusion of an antigenic peptide, TCS, and a cell-penetrating peptide (CPP), termed an "all-in-one" vaccine, for transcutaneous cancer immunization. The TCS adjuvant effect on antigen presentation was investigated and the antitumor immunity of the vaccines was investigated using the different tumor models. The vaccines were prepared

Generated SecPen_NY-ESO-1_ubiquitin-pulsed dendritic cell cancer vaccine elicits stronger and specific T cell immune responses

Dendritic cell-based cancer vaccines (DC vaccines) have been proved efficient and safe in immunotherapy of various cancers, including melanoma, ovarian and prostate cancer. However, the clinical responses were not always satisfied. Here we proposed a novel strategy to prepare DC vaccines. In the present study, a fusion protein SNU containing a secretin-penetratin (SecPen) peptide, NY-ESO-1 and ubiquitin was designed and expressed. To establish the DC vaccine (DC-SNU), the mouse bone marrow-derived DCs (BMDCs) were isolated, pulsed with SNU and maturated with cytokine cocktail. Then peripheral blood mononuclear cells (PBMCs) from C57BL/6 mice inoculated intraperitoneally with DC-SNU were separated and cocultured with MC38/MC38

Ectopically Expressed Membrane-bound Form of IL-9 Exerts Immune-stimulatory Effect on CT26 Colon Carcinoma Cells

IL-9 is a known T cell growth factor with pleiotropic immunological functions, especially in parasite infection and colitis. However, its role in tumor growth is controversial. In this study, we generated tumor clones expressing the membrane-bound form of IL-9 (MB-IL-9) and investigated their influences on immune system. MB-IL-9 tumor clones showed reduced tumorigenicity but shortened survival accompanied with severe body weight loss in mice. MB-IL-9 expression on tumor cells had no effect on cell proliferation or major histocompatibility complex class I expression in vitro. MB-IL-9 tumor clones were effective in amplifying CD4⁺ and CD8⁺ T cells and increasing cytotoxic activity against CT26 cells in vivo. We also observed a prominent reduction in body weights and survival period of mice injected intraperitoneally with MB-IL-9 clones compared with control groups. Ratios of IL-17 to interferon (IFN)-γ in serum level and tumor mass were higher in mice implanted with MB-IL-9 tumor clones than those observed in mice implanted with control cells. These results indicate that the ectopic expression of the MB-IL-9 on tumor cells exerts an immune-stimulatory effect with toxicity. To exploit its benefits as a tumor vaccine, a strategy to control the toxicity of MB-IL-9 tumor clones should be developed.

Effect of the novel immunomodulator composed of muramyl dipeptide and anti-CD10monoclonal antibody on dendritic cells in children with acute leukemia / 中华实用儿科临床杂志

Objective To study the effect of a new immunomodulator composed of muramyl dipeptide(MDP) and anti-CD10monoclonal antibody(MDP-Ab)on the dendritic cells(DC)of children with acute leukemia. Methods DC was adopted to divide the children with acute lymphoblastic leukemia into 6 groups,including the control group,unconjugated anti-CD10alone,unconjugated MDP alone,MDP-Ab alone,lipopolysaccharide(LPS)alone and MDP-Ab + LPS.The immunophenotypes,the endocytosis interleukin-12(IL-12)were detected.The stimulation index of autologous lymphocytes was assayed by adopting 5-(and 6)-carboxyfluorescein diacetate,succinimidyl es-ter(CFSE)-staining method.The supernatants of DC and autologous lymphocytes were used to detect the level of in-terferon-γ(IFN-γ)by using enzyme-linked immunosorbent assay.Results (1)DC immunophenotype:The ex-pressions of human leukocyte antigen-DR(HLA-DR),mature molecule(CD83)and co-stimulatory molecules (CD80and CD86)were increased significantly upon DC triggered with MDP-Ab,compared with the control group,un-conjugated anti-CD10group,and unconjugated MDP group,but lower than those in LPS and combination of MDP-Ab with LPS(F=629.62,P=0.000).(2)The level of IL-12:a significant increase in IL-12 level was detected in MDP-Ab group,LPS group,and combination of MDP-Ab with LPS group,compared with the control group,uncon-jugated anti-CD10group,and unconjugated MDP group(F=857.87,P=0.000). There were significant differences among the first three groups.(3)Endocytosis assay:The uptake of DCs stimulated by unconjugated anti-CD10,un-conjugated MDP,MDP-Ab immunoconjugate,LPS or combination was lower than that of immature DC in the control group which was(81.3 ± 10.1)%.(4)Mixed lymphocyte reaction and IFN-γ level:DC,treated with MDP-Ab, LPS and combination,stimulated more CFSE positive cells and higher level of IFN-γ secretion than the control group and unconjugated anti-CD10group,unconjugated MDP group. The most significance was observed in combination of MDP-Ab with LPS(F=393.36,P=0.000;F=2 497.18,P=0.000).Conclusion It is concluded that MDP-Ab could promote the proliferation and maturation of DC derived from blood of children with acute leukemia.

Inductive effect of recombinant MUC1-MBP fusion protein combined with R848 on immune activity of T cells in mice / 吉林大学学报(医学版)

Objective:To study the inductive effect of recombinant MUC1-MBP fusion protein combined with R848 on the immune activity of T cells in the mice,and to provide experimental basis for searching the suitable adjuvants of recombinant MUC1-MBP fusion protein.Methods:A total of 21 C57BL/6 mice were randomly divided into control group(treat with normal saline),MUC1-MBP+R848 group (treated with MUC1-MBP+R848),and MUC1-MBP+baillus calmette guerin(BCG) group(treated with MUC1-MBP+BCG)(n=7).After immunized for 4-7 d,the spleen tissue was taken and the spleen indexes of the mice in various groups were measured;the stimmulus index(SI) of the mice was detected by lymphocyte proliferation response;the levels of tumor necrosis factor-γ(TNF-γ) and interleukin-4(IL-4) were detected by ELISA method;the proprotions of T lymphocyte subsets in spleen cells were analyzed by flow cytometry.Results:Compared with control group,the spleen indexes,SI,and TNF-γ levels of the mice in MUC1-MBP+ R848 and MUC1-MBP+BCG groups were significantly increased (P0.05).Compared with control group,the proprotions of CD3+T,CD4+T,and CD8+ T cells of the mice in MUC1-MBP+ R848 group and MUC1-MBP+BCG group were significantly increased(P<0.05 or P<0.01).Conclusion:Both MUC1-MBP fusion protein combined with R848 and BCG can induce the Th1 type of immune activity in the mice,and R848 is the potential candidate adjuvant for MUC1-MBP.

Supervivencia en pacientes con cáncer pulmonar de células no pequeñas vacunados con CIMAvax-EGF / Survival in patients with non-small cell lung cancer vaccinated with CIMAvax-EGF

Se realizó un estudio observacional, descriptivo y longitudinal en un primer momento, y analítico de cohorte en un segundo tiempo, de 95 pacientes con cáncer de pulmón de células no pequeñas en estadios avanzados, asistidos en el Hospital Provincial Docente Clinicoquirúrgico "Saturnino Lora Torres" y en 4 policlínicos de la ciudad de Santiago de Cuba, durante el período 2006-2013, a fin de estimar la supervivencia en ellos luego de la vacunación con CIMAvax-EGF e identificar los factores asociados a la mortalidad, para lo cual se empleó el método de Kaplan-Meier y el de regresión de Cox, respectivamente. La supervivencia global a los 2 años fue de 20,7 %, con una mediana de 13 meses, en tanto la supervivencia al año de aplicada la vacuna fue de 36,5 %. Por su parte, el estadio IIIB, la respuesta favorable a la primera línea de tratamiento, la combinación quimioterapia-radioterapia-vacuna y la inmunización en 4 o más ocasiones, posibilitaron una supervivencia significativamente mayor. La reacción desfavorable a la primera línea terapéutica constituyó un factor pronóstico del incremento del riesgo de muerte en la población de afectados.

An observational, descriptive and cross-sectional study in a first moment, and cohort analytic in a second time, of 95 patients with non-small cell lung cancer in advanced stages, assisted at "Saturnino Lora Torres" Teaching Clinical Surgical Provincial Hospital and in 4 polyclinics of Santiago de Cuba, was carried out during the period 2006-2013, in order to estimate the survival in them after the vaccination with CIMAvax-EGF and to identify the factors associated to the mortality, for which Kaplan-Meier method and Cox regression were used, respectively. The global survival in 2 years was 20.7%, with a median of 13 months, as long as the survival a year after applying the vaccine was 36.5%. On the other hand, in the stage IIIB, the favorable response to the first line treatment, the chemotherapy-radiotherapy-vaccine combination and the immunization in 4 or more occasions, facilitated a significantly higher survival. The unfavorable reaction to the first therapeutic line constituted a prediction factor of death risk increase in the population affected.

Immunotherapy and cell therapy for cancer / 中国药理学与毒理学杂志

Cancer immunotherapies are recently gaining attention as viable therapeutic options. There are two types of immunotherapy:passive and active. The passive immunotherapies include several treatments such as monoclonal antibodies,either alone or as antibody-drug conjugates. The active immunotherapies include cancer vaccines which utilize the patient′s own cells as antigen presenting cells and target specific cancer antigens,and chimeric antigen receptor T-cell(CAR-T)therapy which engineers a patient′s T-cells to recognize cancer antigens through chimeric antigen receptors. Recent successes include the US FDA approval of a number of cancer immunotherapies such as treatments utilizing monoclonal antibodies against immune checkpoint inhibitors,the Provenge cancer vaccine that targets prostrate cancer,and a CAR-T against relapsed/refractory acute lymphoblastic leukemia that was designated with breakthrough drug status,all of which has had drug companies investigating cancer immunotherapies with intense enthusiasm. In this review we discuss where the field of immune-oncology stands today,highlight the latest findings and hypothesize future directions.

Research on mechanism of GM-CSF secreting liver cancer vaccine on CTL killing activity of transplanted liver cancer mice / 中国生化药物杂志

Objective To study the effect of granulocyte-macrophage colony-stimulating factor ( GM-CSF) secreting liver cancer vaccine on killing activity of cytotoxic T lymphocytes ( CTL) of transplanted liver cancer mice and its mechanism.Methods There were three groups:liver cancer vaccine group (A group), liver cancer group (B group) and PBS group (C group).The transplanted liver cancer model was builded with injection of H 22 hepatoma cells, while the GM-CSF secreting liver cancer vaccine group and PBS group was builded.GM-CSF secreting liver cancer vaccine group and PBS group were establised.The levels of CD8 +T cell in peripheral blood were detected by flow cytometry.The killing activity of cytotoxic T lymphocytes ( CTL) of spleen cells was detected by MTT method.The expression levels of tumor necrosis factor-α( TNF-α) and interferon-γ(γ-INF) were detected by Western blot.Results The flow cytometry results showed that, compared with B group, the levels of CD8 +T cell of A group significantly increased (P<0.01).MTT results showed that, compared with B group, the killing activity of cytotoxic T lymphocytes (CTL) in A group significantly increased (P<0.01).Western blot results showed that, compared with B group, the expression levels of tumor necrosis factor-α(TNF-α) and interferon-γ(γ-INF) in A group significantly decreased (P<0.01).Conclusion GM-CSF secreting liver cancer vaccine can significantly inhibit the activity of H22 cell, and its possible mechanism of action may be to activated CD8 +T expression, improve cytotoxic activity of CTL of spleen cells, and reduce TNF-αand γ-INF protein expression.

Preparation of leukemia cell vaccine expressing Bacille Calmette-Guérin heat shock protein 70 and its anti-leukemia therapeutic effect / 中华实用儿科临床杂志

Objective To culture the acute leukemia cells in vitro,and to prepare cancer vaccine expressing heat shock protein 70 (HSP70) of Bacille Calemette-Geérin(BCG) onto the cell surface,so as to study its anti-tumor effect and mechanism.Methods Acute myeloid leukemia (AML) cells were cultured in a serum-free Stemspan(H) culture supplemented with cytokines [stem cell factor(SCF),flt-3 ligand (FL),interleukin (IL)-3 and IL-6] in vitro.And B-lineage acute lymphoblastic leukemia (B-ALL) cells were cultured in a Iscove modified medium(IMDM) culture supplemented with cytokines (SCF,FL,IL-3 and IL-7) in vitro.Cellular morphology was observed by the microscopy and immunophenotype determination was used to verify the biological characteristics of acute leukemia cells after culture.Lipofectamine 2000 was used to transfect the pDisplay-HSP70 plasmid into acute leukemia cells.The expression of HSP70 on the cell surface was detected by fluorescene microscope.Then the immunogenicity of the leukemia cells expressing HSP70 were detected.The experimental groups were divided into 3 subgroups:the wide-type acute leukemia cells (wt-LC group),the pDisplay-leukemia cells (pDisplay-LC group),and the pDisplay-HSP70-leukemia cells (HSP70-LC group),respectively.The leukemia cells in different groups were cultured with autologous peripheral blood T cells for 72 hours.The proliferation indices of T cells were assayed by carboxyfluorescein diacetate succinimidyl ester (CFSE)-staining method,and the contents of interferon-γ(IFN-γ) were tested by enzyme-linked immunosorbent assay (ELISA).The leukemia cells in different groups were cultured with autologous peripheral blood T cells,and after 6 days,the fresh acute leukemia cells were added [in the different ratios of cytotoxicity T lymphocyte (CTL):leukemia cells were 10 ∶ 1,20 ∶ 1,40 ∶ 1 and 80 ∶ 1] and continued to be cultured for another 12 hours.Cytotoxicity assay was measured by lactate dehydrogenase (LDH) release.Results After short term culture in vitro,the leukemia cells were in colony-like suspension and maintain the proliferation characteristics were maintained.The cell proliferation was rapidly cultured for about 10 days and then was gradually slowed down.But there was no difference between the day 10 and day 0 in the expressions of CD13 and CD33 in fifteen cases of AML cells (P ＞ 0.05).Equally,there was no difference between the day 10 and day 0 in the expressions of CD19,CD10 and CD22 in fifteen cases of B-ALL cells (P ＞ 0.05).After BCG HSP70 gene transfection,the yellow-green fluorescence on the leukemia cells surface was observed under the confocal microscope.Detection of the immunogenicity:(1) Autologous T cell proliferation:the most significant T cell proliferation was observed in the group of HSP70-transfected leukemia cells (t =17.89,19.58,all P ＜0.05).There was no difference between the wt-LC group and pDisplay-LC group (P ＞ 0.05).(2) The contents of cytokines:the IFN-γ level in the group of HSP70-transfected leukemia cells was higher than those of wide-type acute leukemia cells and the pDisplay-transfected ones (t =24.72,24.81,all P ＜ 0.05).(3) Cytotoicity of CTL:the killing rate in HSP70-transfected leukemia cells was significantly higher than those of wide-type acute leukemia cells and pDisplay——transfected ones(F =13.66,P ＜ 0.05).And with the increase of the ratio from 10 ∶ 1 to 80 ∶ 1,the inhibiting activity of CTL in the HSP70-LC group was raising(F =19.69,P ＜ 0.05).Conclusions Fresh acute leukemia cells can be successfully cultured in vitro.Short-term culture can significantly increase the number of leukemia cells,but has little effect on surface antigen expression.So,the biological characteristics of the leukemia cells can be maintained.The leukemia cells vaccine expressing BCG HSP70 onto its surface was successfully prepared,and gene transfection of BCG HSP70 can significantly enhance the immunogenicity of leukemia cells.

Live bacterial vaccine vectors: An overview

Genetically attenuated microorganisms, pathogens, and some commensal bacteria can be engineered to deliver recombinant heterologous antigens to stimulate the host immune system, while still offering good levels of safety. A key feature of these live vectors is their capacity to stimulate mucosal as well as humoral and/or cellular systemic immunity. This enables the use of different forms of vaccination to prevent pathogen colonization of mucosal tissues, the front door for many infectious agents. Furthermore, delivery of DNA vaccines and immune system stimulatory molecules, such as cytokines, can be achieved using these special carriers, whose adjuvant properties and, sometimes, invasive capacities enhance the immune response. More recently, the unique features and versatility of these vectors have also been exploited to develop anti-cancer vaccines, where tumor-associated antigens, cytokines, and DNA or RNA molecules are delivered. Different strategies and genetic tools are constantly being developed, increasing the antigenic potential of agents delivered by these systems, opening fresh perspectives for the deployment of vehicles for new purposes. Here we summarize the main characteristics of the different types of live bacterial vectors and discuss new applications of these delivery systems in the field of vaccinology.

Immunotherapy of liver cancer: open label phase II clinical study / Шинэ санаа Шинэ нээлт

Background: Hepatocellular carcinoma (HCC) is a global health problem and chronic hepatitis B and C infections account for majority of liver cancer cases. HCC is the most common malignancy in Mongolia with high fatality rate; highlighting the unmet need for better treatments. The increasing number of clinical studies is now devoted to development of various immunotherapies. Objective: To evaluate the clinical benefit of an oral immunomodulator derived from pooled blood of hepatitis B and C virus carriers - originally indicated for treatment of chronic hepatitis as a therapeutic vaccine. Patients: Nine female and twelve male patients between ages 51-71 (median 59.2) presented with advanced, inoperable HCC characterized by elevated serum levels of alpha-fetoprotein (AFP) biomarker. As no other treatment options were available, patients consented to receive one daily tablet of vaccine. Results: After average 2.2 months of treatment 19 out of 21 (90.5%) patients experienced six-fold decrease of AFP from median 122.5 to 19.2 IU/ml (P<0.002 by Wilcoxon matched-pairs test); of these eight (42.1%) had exhibited levels (median 4.4 IU/ml) below upper limit 10 IU/ml of normal range. The decrease in AFP was correlated with tumor clearance or regression on CT scan. Two patients who did not experienced decline in AFP had died, the remaining are alive after median follow-up of 11 months (range 1-57), which is 3.7-times longer than 3 months survival in historical controls with advanced HCC (P<0.0001). None of patients experienced adverse effects. Conclusion: The results suggest that our immunotherapy holds promise as safe, effective and fast-acting intervention for HCC. Further studies are required to confirm this preliminary observation.

Alpha-galactosylceramide loaded tumor cells in combination with TLR9 agonists induce potent anti-tumor responses in a murine model of colon cancer / 中华微生物学和免疫学杂志

Objective To design a new cancer vaccine by using alpha-galactosylceramide (α-Galcer,α-GC) loaded tumor cells in combination with TLR 9 ligand and to evaluate its therapeutic effects on colon canc-er in mice.Methods MC38 cells were transfected with lentivirus (GFP-CD1d) to prepare CD1d-MC38 cells. The expression of CD1d molecules in CD1d-MC38 cells was detected by fluorescence microscopy , RT-PCR and flow cytometry.The sorted CD1d-MC38 cells were loaded with α-Galcer to prepare CD1d-MC38/α-GC complex. Flow cytometry was performed to evaluate the efficiency of combination .A mouse model of colon cancer was es-tablished to investigate the therapeutic effects of α-Galcer loaded tumor cells in combination with TLR 9 ligand ( CD1d-MC38/α-GC+CpG1826) on colon cancer in mice by analyzing tumor growth and mice survival time .Im-munohistochemical staining was used to detect CD 4+T and CD8+T infiltrating lymphocytes in tumor tissues .Re-sults The MC38 cancer cells that expressed CD 1d and GFP were successfully constructed , among which 98.10%±2.53%were positive for CD1d.Moreover, the CD1d-MC38 cells could combine with α-Galcer effec-tively in a dose and time dependent manner .Compared with PBS treated group ,α-GC treated group and TLR9 ligand treated group , the experimental vaccine strategy was sufficient to inhibit the growth of established tumors and prolong survival of tumor-bearing mice (P<0.01).Immunohistochemistry analysis revealed that levels of CD4+T cells and CD8+T cells in experiment group were significantly higher than those in groups treated with PBS,α-GC and TLR9 ligand (P<0.01).Conclusion CD1d-MC38/α-GC in combination with CpG1826 could efficiently inhibit the growth of established tumors and prolong survival of tumor-bearing mice .Immunohisto-chemistry analysis revealed that CD 4+T cells and CD8+T cells played important roles in anti-tumor immunity.

Preparation of HL-60 cell vaccine expressing BCG-HSP70 and its anti-leukemia effect / 临床儿科杂志

Objectives To prepare the HL-60 cell vaccine expressing heat shock protein 70 (HSP70) of Bacille calmette-Guérin (BCG), so as to study its anti-tumor effect and mechanism. Methods The whole BCG HSP70 gene was amplified from BCG genome by polymerase chain reaction (PCR) and sub-cloned into the polyclone endonuclease sites in pDisplay. The recom-binant vector of pDisplay-HSP70 was verified by sequencing. Then the HL-60 cell vaccine expressing the protein onto the cell surface was prepared by lipofectamine transfection. To detect the immunogenicity of HL-60 cells expressing HSP70, the test groups were divided into three subgroups, HL60-wt, HL60-pDisplay, and HL60-HSP70 respectively. Each group was cultured with peripheral blood T cells for 72 h, then the proliferation indices of T cells were assayed by CFSE-staining method, and IFN-γwere tested by enzyme-linked immunosorbent assay (ELISA). The HL-60 cells of different groups were cultured with peripher-al blood T cells for 6d. The wild-type HL-60 cells were added and co-cultured for another 12h. Cytotoxicity assay was measured by LDH release. Results (1) The fragment of BCG HSP70 was consistent with the theoretical value. DNA sequencing showed that the recombinant vector of pDisplay-HSP70 was correctly constructed. (2) BCG HSP70 expressed onto the HL-60 cells sur-face. (3) Detection of the immunogenicity: ①The most significant T cell proliferation was observed in the group of HSP70-transfected HL-60 cells (P0.05).②The contents of IFN-γof the HSP70-HL60 group was the highest.③The inhibiting activity of CTLs on HL-60 cells in the group of HSP70-transfected HL-60 cells was more significant than that of wide-type and pDisplay--transfected HL-60 cells. And with the increase of the E:T ratio, the inhibiting activity of CTLs in the HSP70-HL60 group was rising. Conclusions The recombinant eukaryotic expression vector (pDisplay-HSP70) of BCG HSP70 was successfully constructed. And the HL-60 cell vaccine expressing BCG HSP70 onto its surface was successfully prepared. The results showed that gene transfection of BCG HSP70 could significantly enhance the immunogenicity of HL-60 cells.

Anti-tumor effect of tumor vaccine combined with metronomic chemotherapy on breast cancer in mice / 中国肿瘤临床

Objective:This study aimed to observe the synergistic effect of a new tumor vaccine combined with metronomic che-motherapy in vivo on breast cancer. This study was also conducted to investigate the mechanism of this combination. Methods:Balb/c mice inoculated with 4T1 mouse breast cancer cell were used as tumor models. High-mobility group nucleosome-binding protein 1 (HMGN1) gene was used to transfect 4T1 cell lines as cancer vaccines. After 4T1 cell was inoculated, the mice were randomized into four groups:normal saline (NS);metronomic gemcitabine (GEM) alone;cancer vaccine alone;and combination therapy group. Tumor growth and potential toxicities of these regimens were observed. The Foxp3 expression of regulatory T cells (Tregs) was detected by western blot and immunohistochemical staining. The microvessel density (MVD) of the tumor was also detected by immunohistochemi-cal staining. Results:The tumor volume of the mice was significantly lower in the combination group than in the MET group or cancer vaccine group (P<0.05). This result exhibited a higher significant difference than the tumor volume of the mice in the NS group (P<0.01). Foxp3 expression was significantly lower in the mice treated with GEM (combination or MET group). MVD was significantly lower in these two groups than in the cancer vaccine group or NS group (P<0.05). Furthermore, adverse reactions slightly occurred in each group. Conclusion: The combination of cancer vaccines and metronomic GEM is a very active and well-tolerated regimen for breast cancer in mice.

EHA 2013: progress in study of cancer vaccination and its application in hematological malignancies / 白血病·淋巴瘤

There are 5 literatures related to the clinical applications of cancer vaccination in hematologieal malignancies in the 18th annual meeting of the European Hematology Association (EHA).This article provides an overview of these literatures that helps to understand how cancer vaccination can be explored for future clinical interventions.

Enhanced anti-tumor effect of a gene gun-delivered DNA vaccine encoding the human papillomavirus type 16 oncoproteins genetically fused to the herpes simplex virus glycoprotein D

Anti-cancer DNA vaccines have attracted growing interest as a simple and non-invasive method for both the treatment and prevention of tumors induced by human papillomaviruses. Nonetheless, the low immunogenicity of parenterally administered vaccines, particularly regarding the activation of cytotoxic CD8+ T cell responses, suggests that further improvements in both vaccine composition and administration routes are still required. In the present study, we report the immune responses and anti-tumor effects of a DNA vaccine (pgD-E7E6E5) expressing three proteins (E7, E6, and E5) of the human papillomavirus type 16 genetically fused to the glycoprotein D of the human herpes simplex virus type 1, which was administered to mice by the intradermal (id) route using a gene gun. A single id dose of pgD-E7E6E5 (2 µg/dose) induced a strong activation of E7-specific interferon-γ (INF-γ)-producing CD8+ T cells and full prophylactic anti-tumor effects in the vaccinated mice. Three vaccine doses inhibited tumor growth in 70 percent of the mice with established tumors. In addition, a single vaccine dose consisting of the co-administration of pgD-E7E6E5 and the vector encoding interleukin-12 or granulocyte-macrophage colony-stimulating factor further enhanced the therapeutic anti-tumor effects and conferred protection to 60 and 50 percent of the vaccinated mice, respectively. In conclusion, id administration of pgD-E7E6E5 significantly enhanced the immunogenicity and anti-tumor effects of the DNA vaccine, representing a promising administration route for future clinical trials.

Efficacy of leukemia vaccine combined 1-MT immune treatment of tumor-bearing mice / 白血病·淋巴瘤

Objective To explore the active immunotherapeutic effects of whole-cell leukemia vaccine combined with 1-methyl-tryptophan (1-MT, inhibitor of idoleamine 2,3-dioxygenase, IDO) treatment on leukemia. Methods The tumor-bearing mice model was made by hypodermic injection of FBL-3 cells. Then these mice were divided into 5 groups, normal group, PBS control group, CTX chemotherapy group, vaccine treated group and vaccine combined with 1-MT treated group (1-MT group), respectively. The main outcome measures including general condition, response rate, tumor size, metastasis and survival time were investigated. Results The mice of PBS control group were slow to move and much heavier (including tumor nodules) than the other groups. No obvious difference was observed in activity, eating behavior and weight between normal group, vaccine treated group and 1-MT treated group. The mice of CTX chemotherapy group were observed epilation, arched body and worn, and those weights decreased significantly compared with other group. The treatment-related mortality of vaccine-treated group and 1-MT group was lower than that of CTX chemotherapy group significantly (0, 0 vs 40 %). There were no significant difference in complete remission rates between vaccine treated group and 1-MT group (61.1 % vs 70.0 %, χ2 = 0.221, P >0.05). But the recurrence rate of 1-MT group was lower than vaccine treated group (0 vs 36.36 %). The tumor nodules growth of recurrent mice could be inhibited by 1-MT. The mean survival time of vaccine treated group and 1-MT group were longer than that in CTX chemotherapy group and PBS control group (χ2 = 52.13, P <0.01). Conclusion Whole-cell leukemia vaccine can inhibit tumor growth and prolong tumor-bearing mice survival time with remarkable curative effects and few side effects. Vaccine combined with 1-MT treatment can significantly reduce tumor recurrence rate, and 1-MT was still effective in inhibiting recurrence of tumor nodules growth after vaccine treatment.