There are multiple types of inhibitory immune cells in tumor. Among these cells, Treg (regulatory T cell) plays an extremely important role in tumor development and progression. Treg exihibits potent inhibitory effects on effector cells by a variety of mechanisms, which might be the the key factor for tumor immune escape. These mechanisms include inhibiting the effector cell function by inhibitory cytokines, killing effector cells by granzyme and profrin, interfering effector cell metabolism, and affecting Treg differentiation and proliferation by regulating the function of dendrtic cells, etc. The research on Treg has provided new strategies for tumor immunotherapy. Tumor immunotherapies targeting Treg and related immunosuppressive factors, such as deleting Treg nonsepcificlly or sepcificlly controling the numbers and functions of Treg, might have a bright future in clinical application.keyword regulatory T cell(Treg); neoplasms; immune escape; immunotherapy

Lappaconitine hydrobromide can remove inflammation and swelling, lower temperature and relieve heat. It also can be used for local anesthesia. Clinically lappaconitine hydrobromide can be applied via i.v., i.m. or p.o. for analgesic treatment. Lappaconitine has better effect for moderate pain than for severe pain, which may be associated with the low dose. Future efforts should be made in increasing dosage, combining lappaconitine hydrobromide with other drugs and improving drug delivery technique.

The Renca-bearing mice were treated by combined fibroblast-mediated IL-2 and G-CSF gene therapy. The survival periods of Renca-bearing mice were prolonged markedly and 75% of Renca-bearing mice were cured. The spleens of Renca-bearing mice treated by fibroblast-mediated G-CSF gene therapy were larger than the spleens of other mice. Histologic analysis of tumor showed that there were a number of infiltrating eosinophils. The NK, LAK and CTL activity induced from the splenocytes of the tumor-bearing mice increased siginificantly when the mice were treated by fibroblast-mediated IL-2 gene therapy and the cytotoxicity of macrophages also increased. The results demonstrated that the and - tumor responses might be induced more significantly by combined fibroblast-mediated IL-2 and G-CSF gene therapy and better antitumor effect may be achieved.

The Ad-IL-2 and/or Ad-IL-3 were i. p. injected into experimental leukemic mice after high dose chemotherapy. When Ad - LacZ was i. p. injected into leukemic mice, there were leukemic cells in bone marrow, vessal, liver and spleen. After i. p. injection of Ad-IL-2 and/or Ad-IL-3, the leukemia - bearing mice showed significant inhibition of tumor growth. As i.p. injection of Ad-IL-2, the splenic NK, CTL activity increased; as i. p. injection of Ad - IL - 3, the number and cytotoxicity of peritoneal macrophages were significantly higher than that of the control groups. After i. p. injection of Ad - IL - 2 and Ad - IL - 3 at the same time, the anti - leukemia activity was the best. Though there were less leukemic cells in the bone marrow, there were no leukemic cells in the liver and spleen. Our results suggested that i. p. injection of Ad - IL - 2 and Ad - IL - 3 could significantly enhance the anti - leukemia activity of chemotherapy.

Dendritic cells (DC) are antigen presenting cells (APC) that play critical roles in the initiation of T cell response and development of T cell-dependent antibodies in vivo. CD34_+ hematopoietic progenitor cells of bone marrow and peripheral blood can differentiate into DC when cultured with GM-CSF and TNF-? in vitro. In the present study, we cultured monocytes isolated from human peripheral blood with 100ng/ml hGM-CSF and 500U/ml hIL-4 for one week, and then found that a large number of DC with high purity were gengerated. DC expressed MHC I , MHC II and costimuladng moleculers highly on cell surface and cound stimulate proliferation of allogeneic T lymphocytes. Self serum or fetal calf serum are best for generation of DC. When hGM-CSF was used alone, the monocytes differentiated into macrophages but not to DC. TNF-? could induce further maturation of DC when added in late period of the culture. Generation of DC from human peripheral blood may facilitate further studies on DC and their clinical applications.

After murine fetal liver cells (FLC) were transfected with granulocyte-macrophage colony-stimulating factor (GM-CSF) gene by recombinant adenovirus and intrasplenically transplanted into allogeneic mice, the effects of GM-CSF gene-transfected FLC on the recovery of immune response inhibited by chemotherapy were observed. The number of CD4 + cells and the ratio of CD4 + /CDS + cells from peripheral blood lymphocytes increased significantly. The cytotoxicity of the NK cells and the proliferation response of splenocytes to ConA, LPS elevated markedly, but the same results were not from bone marrow. These data demonstrated that intrasplenic transplantation of GM-CSF gene-transfected FLC could effectively accelerate the recovery of immune response after high-dose chemotherapy.

Radiotherapy is one of major cancer treatment methods.However,radiation resistance is an important reason to restrict the efficacy of radiotherapy and lead to treatment failure.In recent years,the relationship between the canonical Wnt signaling pathway and tumor radiation resistance has more and more attention of the scholars.This review summarized recent ten years findings concerning the canonical Wnt signaling pathway and tumor radiation resistance and tried to find some valuable rules or some internal relationships among different pathways by systemically analyzing.

OBJECTIVE:To study the anti-tumor effects of Vinblastine (VLB) hydrophilic group modified cationic liposomes in tumor-bearing mice. METHODS:Tumor-bearing model were induced by inoculating yellow ascites of S180 ascites tumor mice. Tumor-bearing mice were randomly divided into model group,VLB sulfate injection group,VLB liposomes group,VLB hydrophil-ic group modified liposomes group,VLB cationic liposomes group and VLB hydrophilic group modified cationic liposomes group, i.e. group A,B,C,D,E and F,with 18 mice in each group. Group A was given normal saline intravenously via mice tail,other groups were given VLB 1.5 mg/kg every 2 days for consecutive 5 times. The anti-tumor effects of different VLB preparations were compared,using living conditions,survival time,tumor volume and weight,and tissue pathological section as indexes. RE-SULTS:Compared with group A,B,C,D and E,the mice of group F were more active,and had longer survival time,smaller tumor volume and lighter tumor weight,with statistical significance(P<0.05). The tissue pathological section of mice in group F indicated that coagulation necrosis,disintegration,and dissolution of tumor cell nucleus. CONCLUSIONS:VLB hydrophilic group modified cationic liposomes have obvious anti-tumor effect,which are better than other VLB preparations.

Objective: To study the treatment of experimental lung metastasis by intratracheal injection of IL 18 gene recombinant adenovirus. Methods: (1)The mouse IL 18 mRNA was detected by RT PCR, the concentrations of IL 18, associated cytokines in lung lavage and blood were determined by ELISA at different times after intratracheal injection of IL 18 recombinant adenovirus. (2)The lung metastasis nodes, mouse survival period, survival rates were investigated in the treatment of experimental lung metastasis in C57BL/6 mouse model. The NK activity and CTL activity were determined by 51 Cr 4 h release method. Results: (1)The IL 18 mRNA could be detected in lung tissue 6 h after intratracheal use of IL 18 recombinant adenovirus, and the concentrations of IL 18 in lung lavage was higher than that of peripheral blood, and both IL 18 mRNA and IL 18 could not be detected in control groups. (2)Intratracheal use of IL 18 recombinant adenovirus had significant therapeutic effect on experimental lung metastasis with the results of increased CTL and NK activity, and with longer survival period and higher survival rates compared with the control groups. Conclusion: Intratracheal usage of adenovirus vector containing IL 18 gene has therapeutic effect on the lung metastasis, denoting that gene therapy of lung diseases can be done through airway directly with recombinant adenovirus.

Objective Evaluate the accuracy o f co-registration of PET and C T (PET-CT) images on line with phantom, and utilize it on patients to provide c l inical evidence for target delineation in radiotherapy. Methods A phantom with m arkers and different volume cylinders was infused with various concentrations of 18FDG, and scanned at 4?mm by PET and CT respectively. Aft er having been transmi tted into GE eNTEGRA and treatment planning system (TPS) workstations, the image s were fused and reconstructed. The distance between the markers and the errors were monitored in PET and CT images respectively. The volume of cylinder in PET and CT images were measured and compared by certain pixel value proportion deduc tion method. The same procedure was performed on the pulmonary tumor image in te n patients. Results eNTEGRA and TPS workstations had a good length linearity, b ut the fusion error of the latter was markedly greater than the former. Tumors i n different volume filled by varying concentrations of 18FDG required different pixel deduction proportion. The cylinder volume of PET and CT images were almost the same, so were the images of pulmonary tumor of ten patients. Conclusions T he accuracy of image co-registration of PET-CT on line may fulfill the clinica l demand. Pixel value proportion deduction method can be used for target delineati on on PET image.