ABSTRACT
Objective:To explore the antitumor effect of ADU-S100/doxorubicin in situ vaccine on diffuse large B-cell lymphoma (DLBCL) and its mechanism.Methods:The 6-week-old female BALB/c mice were selected, and the bilateral murine subcutaneous B-cell lymphoma model was established with murine B-cell lymphoma A20 cells. The subcutaneous tumor-bearing mice were randomly divided into untreated group (without treatment), ADU-S100 in situ vaccine treatment group (intratumoral injection of interferon gene stimulating factor agonist ADU-S100), doxorubicin in situ vaccine treatment group (intratumoral injection of doxorubicin), and ADU-S100/doxorubicin in situ vaccine treatment group (intratumoral injection of ADU-S100 and doxorubicin) by using random number table method, with 5 mice in each group. The right tumors of the bilateral subcutaneous tumor-bearing mice were defined as proximal tumors, and the left tumors of the bilateral subcutaneous tumor-bearing mice were defined as distal tumors. Only the proximal tumors were treated via the intratumoral route, and the distal tumors were not treated. On day 23 after tumor inoculation, the percentages of CD11c + dendritic cells (DC), CD8 + CD11c + DC and CD80 + CD11c + DC in the spleen of mice in each group were detected by flow cytometry. The splenocytes of mice in each group were stimulated with A20 tumor cell lysate in vitro, the percentages of 5'-ethynyl-2'-deoxyuridine-positive (EdU +) cells and tumor necrosis factor-α-positive (TNF-α +) cells in CD8 + T cells in each in situ vaccine treatment group were detected by flow cytometry, and the killing effect of cytotoxic T lymphocyte (CTL) in each group was measured by using the lactate dehydrogenase (LDH) cytotoxicity assay kit. The mice treated with ADU-S100/doxorubicin in situ vaccine were intraperitoneally injected with anti-mouse CD8α (clone 53-6.7) mAb or isotype control on days 7, 12 and 17 after tumor inoculation to eliminate CD8 + cells. On day 23 after tumor inoculation, the proximal and distal tumor volumes of mice in the ADU-S100/doxorubicin in situ vaccine combined with anti-mouse CD8α (clone 53-6.7) mAb or isotype control treatment group were measured, the percentages of CD8 + T cells and CD8 + CD11c + DC in the spleen of tumor-bearing mice in these two groups were detected by flow cytometry, and the infiltration of CD8 + T cells in the tumor tissues from these two groups was detected by immunohistochemistry (IHC) staining. Results:On days 11, 14, 17, 20 and 23 after tumor inoculation, the proximal and distal tumor volumes of mice in each treated group were lower than those in the untreated group (all P < 0.05). The proportions of CD11c + DC in the spleen of the untreated group, ADU-S100 in situ vaccine treatment group, doxorubicin in situ vaccine treatment group and ADU-S100/doxorubicin in situ vaccine treatment group were (4.92±0.63)%, (7.54±0.84)%, (7.45±0.86)% and (11.63±0.85)%, respectively, and the difference was statistically significant ( F = 72.30, P < 0.001); the proportions of CD8 + CD11c + DC were (1.36±0.34)%, (4.02±0.43)%, (4.22±0.61)% and (6.11±0.73)%, respectively, and the difference was statistically significant ( F = 76.09, P < 0.001); the proportions of CD80 + CD11c + DC were (0.51±0.24)%, (1.69±0.23)%, (1.82±0.25)% and (4.09±0.39)%, respectively, and the difference was statistically significant ( F = 167.40, P < 0.001). The CTL responses and the proportion of EdU + cells and TNF-α + cells in CD8 + T cells in each in situ vaccine treatment group were higher than those in the untreated group (all P < 0.05). Furthermore, the enhanced CTL responses and the increased proportion of EdU + cells and TNF-α + cells in CD8 + T cells were observed in the ADU-S100/doxorubicin in situ vaccine treatment group as compared to the ADU-S100 in situ vaccine treatment group and doxorubicin in situ vaccine treatment group (all P < 0.05). The proportions of CD8 + T cells and CD8 + CD11c + DC in the spleen of mice treated with ADU-S100/doxorubicin in situ vaccine and anti-mouse CD8α mAb were lower than those in ADU-S100/doxorubicin in situ vaccine and isotype control group (both P < 0.05) and both proximal and distal tumor volumes of mice treated with ADU-S100/doxorubicin in situ vaccine and anti-mouse CD8α mAb were larger than those in ADU-S100/doxorubicin in situ vaccine and isotype control group (both P < 0.05). Conclusions:ADU-S100/doxorubicin in situ vaccine can induce profound regression of proximal tumors in bilateral murine subcutaneous B-cell lymphoma model and generate systemic immune responses capable of partially inhibiting distant tumor growth, and the antitumor efficacy of ADU-S100/doxorubicin in situ vaccine may require CD8 + CD11c + DC-mediated CD8 + T cell immune responses.
ABSTRACT
Objective To investigate the expression of zinc finger protein 382(ZNF382)in diffuse large B-cell lymphoma(DLBCL)tissue and its relationship with clinical pathological characteristics and prognosis of DLBCL patients.Methods A total of 57 DLBCL patients admitted to the Department of Hematology,Luoyang Central Hospital from January 2014 to December 2018 were selected as the research subjects.The biopsy pathological specimens and clinical data of DLBCL patients were collected;another 20 patients of reactive proliferative lymph node tissue preserved in the Department of Pathology,Luoyang Central Hospital were taken as the control group.The expression of ZNF382 in DLBCL tissue and reactive proliferative lymph node tissue was detected by En vision two-step method.The difference of ZNF382 expression was compared between DLBCL tissue and reactive proliferative lymph node tissue.The correlations of ZNF382 expression with the clinical features such as age,gender,primary tumor site,Ann Arbor stage,international prognostic index(IPI)score,Hans typing,B-symptoms,bone marrow infiltration,giant masses,Eastern Cooperative Oncology Group(ECOG)score,β2-microglobulin(β2-MG),serum lactate dehydrogenase(LDH),Ki67,and chemotherapy regimen of DLBCL patients were analyzed by univariate analysis;the survival curve was drawed by Kaplan Meier method,and the univariate and multivariate survival analysis were performed by log-rank tests and Cox proportional risk regression models.Results The expression level of ZNF382 in DLBCL tissue was significantly lower than that in reactive proliferative lymph node tissue(Z=-5.056,P＜0.01).The expression level of ZNF382 was correlated with IPI score,Ann Arbor stage,Hans typing,B-symptoms,bone marrow infiltration and giant masses of DLBCL patients(P＜0.05);the expression level of ZNF382 was not associated to gender,age,primary site,ECOG score,β2-MG,serum LDH,Ki67,and whether the chemotherapy regimen combined with rituximab or not of DLBCL patients(P＞0.05).Among the 57 DLBCL patients,the treatment was effective in 36 patients(63.20％)and ineffective in 21 patients(36.80％);the expression level of ZNF382 in tumor tissue of DLBCL patients with effective treatment was significantly higher than that of DLBCL patients with ineffective treatment(Z=-2.895,P＜0.05).The 2-year event free survival rate of DLBCL patients in the ZNF382 high expression group was significantly higher than that in the ZNF382 low expression group(x2=17.955,P＜0.001).The results of univariate survival analysis showed that female,primary lymph nodes,B-symptoms,bone marrow infiltration,giant masses,IPI score≥3,elevated β2-MG,Ki67＞70％,non-germinal center B-cell-like lymphoma,Ann Arbor stageⅢ-Ⅳ and low expression of ZNF382 were risk factors for poor prognosis in DLBCL patients(P＜0.05).The results of multivariate analysis showed that primary lymph nodes,Ann Arbor stage Ⅲ-Ⅳ and low expression of ZNF382 were independent influencing factors for poor prognosis in DLBCL patients(P＜0.05).Conclusion ZNF382 protein is low expressed in the tumor tissues of DLBCL patients,which is closely related to the occurrence,development and prognosis of DLBCL;and it can be used as an indicator for evaluating the prognosis of DLBCL.