We used retroviral-mediated gene transfer of the human interleukin (IL)-2 gene into murine neuroblastoma cells to investigate whether locally-secreted IL-2 is able to influence the generation of anti-tumor immune responses. Supernatant obtained from cultures of approximately 1 x 10(6) IL-2 gene-transduced, G-418 selected neuro-2a cells was assayed for human IL-2 production by ELISA kit. First, to estimate whether the local secretion of IL-2 from the genetically-modified tumor cells would affect their tumorigenicity in vivo, IL-2-secreting neuro-2a cells were s.c. injected into A/J mice and tumor growth was measured weekly. And to estimate whether IL-2 transfected neuroblastoma cells protect mice from tumor development after wild-type tumor cell challenge, IL-2-secreting neuro-2a cells were s.c. injected into A/J mice. Seven days after IL-2 gene-transfected neuroblastoma cell injection, unmodified neuro-2a cells were s.c. injected into the contralateral site of A/J mice and tumor growth was measured weekly. Finally, to estimate IL-2 effect on pre-established large tumor burdens, IL-2-secreting neuro-2a cells were s.c. injected into A/J mice with established tumor and its growth was measured weekly. The IL-2 gene-transduced neuro-2a clones secreted 120.25-177.3 IU of IL-2 per ml per 10(6) cells during 24 hr. None of the mice injected with IL-2-secreting neuro-2a cells developed tumors within 6 weeks, while all of the mice injected with wild-type neuro-2a cells developed tumors. Immunization of mice with IL-2 gene-transfected, irradiated neuro-2a cells protected these animals against a subsequent challenge with wild-type tumor cells. Finally, the size of large neuroblastomas decreased after IL-2-secreting neuro-2a cell injection into mice. Local secretion of IL-2 gene-transduced tumor cells abrogates their tumorigenicity and induces protective immunity and may inhibit the growth of neuroblastoma.
Animal ; Antibody Formation ; Gene Transfer Techniques* ; Human ; Immunization/methods ; Interleukin-2/therapeutic use ; Interleukin-2/genetics* ; Mice ; Neoplasm Transplantation ; Neuroblastoma/therapy ; Neuroblastoma/prevention & control ; Neuroblastoma/pathology ; Neuroblastoma/genetics* ; Retroviridae/genetics* ; Tumor Cells, Cultured

OBJECTIVESChunghyuldan (CHD), a combinatorial drug that has anti-hyperlipidemic and antiinflammatory activities, has been shown to reduce infarct volume in a focal ischemia-reperfusion rat model. To explore the molecular basis of CHD's neuroprotective effect, we examined whether CHD shows a cell-protective activity and has a regulatory effect on Bax and/or B-cell leukemia/lymphoma 2 (Bcl-2) expression in mouse neuroblastoma 2a (N2a) cells subjected to hypoxia-reoxygenation (H/R).

METHODSIn order to evaluate the effects of CHD on the cytotoxicity induced from hypoxia or H/R condition, lactate dehydrogenase (LDH) assay was performed. To explore whether the suppression of neural damage when pre-treated with CHD is associated with its anti-apoptotic effect, the CHD effect on the expression of Bcl-2 and Bax was analyzed by Western blotting analysis.

RESULTSCytotoxicity of N2a cell line was slightly increased in 42 h hypoxia condition and dramatically increased under the H/R condition. CHD treatment markedly decreased the cytotoxicity in both conditions (P<0.01, P<0.05). H/R markedly increased the expression of the pro-apoptotic protein, Bax, but slightly increased the expression of the anti-apoptotic protein, Bcl-2, compared with the normoxia or hypoxia group. CHD significantly decreased Bax expression (P<0.01) and slightly decreased Bcl-2 expression (P>0.05), resulted in a reduction of Bax/Bcl-2 ratio in N2a cells subjected to H/R.

CONCLUSIONCHD has neuroprotective effect in N2a cells subjected to H/R, which might be derived at least in part from its ability to decrease the expression of the pro-apoptotic protein, Bax.

Animals ; Cell Line, Tumor ; Drugs, Chinese Herbal ; pharmacology ; Hypoxia ; prevention & control ; Mice ; Neuroblastoma ; metabolism ; pathology ; Neuroprotective Agents ; pharmacology ; Reperfusion Injury ; prevention & control

The aim of this study was to investigate the diphtheria-tetanus-pertussis antibody titers after antineoplastic treatment and to suggest an appropriate vaccination approach for pediatric hemato-oncologic patients. A total of 146 children with either malignancy in remission after cessation of therapy or bone marrow failure were recruited. All children had received routine immunization including diphtheria-tetanus-acellular pertussis vaccination before diagnosis of cancer. The serologic immunity to diphtheria, tetanus and pertussis was classified as: completely protective, partially protective, or non-protective. Non-protective serum antibody titer for diphtheria, tetanus and pertussis was detected in 6.2%, 11.6%, and 62.3% of patients, respectively, and partial protective serum antibody titer for diphtheria, tetanus and pertussis was seen in 37%, 28.1%, and 8.9% of patients. There was no significant correlation between the severity of immune defect and age, gender or underlying disease. Revaccination after antineoplastic therapy showed significantly higher levels of antibody for each vaccine antigen. Our data indicates that a large proportion of children lacked protective serum concentrations of antibodies against diphtheria, tetanus, and pertussis. This suggests that reimmunization of these patients is necessary after completion of antineoplastic treatment. Also, prospective studies should be undertaken with the aim of devising a common strategy of revaccination.
Adolescent ; Age Factors ; Antibodies, Bacterial/blood/immunology ; Antineoplastic Agents/therapeutic use ; Child ; Child, Preschool ; Diphtheria/immunology/prevention & control ; Diphtheria-Tetanus-acellular Pertussis Vaccines/*immunology ; Female ; Hematologic Neoplasms/*diagnosis/drug therapy ; Humans ; Immunization, Secondary ; Lymphoma/diagnosis/drug therapy ; Male ; Neuroblastoma/diagnosis/drug therapy ; Sex Factors ; Tetanus/immunology/prevention & control ; Whooping Cough/immunology/prevention & control

OBJECTIVEThe aim of the paper was to improve the prognosis of neuroblastoma (NB) stage III and IV in children through the comprehensive therapy including chemotherapy, delayed tumor resection, autologous stem cell transplantation (ASCT) and inducing differentiation and to analyze the factors affecting the prognosis.

METHODSNewly diagnosed neuroblastoma patients seen from Oct.1998 to Dec.2003 were divided into high, medium and low risk groups depending on clinical stage and age. Comprehensive protocol included accurate staging, delayed and/or second tumor resection for stage III and IV patients, chemotherapy of different intensity mainly composed of cell cycle nonspecific drugs and 13-cis-retinoid for inducing cell differentiation. ASCT was given at the end of therapy for high risk group.

RESULTForty-five patients, 6 months to 11 years of age, 32 males and 13 females, were analyzed. Of them, 15 were found to have the tumor in adrenal gland, 12 had the tumor extended to the retro-peritoneal space, while in 15 cases the tumor was beside the spinal column in chest and in 3 the tumor was located in other places. Nine cases had stage I, 1 case had stage II, 8 cases had III, 26 cases had stage IV and 1 case had stage IVs of the tumor. Depending on the age and stage of the tumor, 26 cases were aligned into high risk protocol, 10 into medium risk and 9 into low risk groups. Thirty nine cases were treated as planned. Eleven of them received ASCT including 2 cases who received second ASCT. Of the thirty-nine patients, 31 achieved complete remission (CR) and 8 partial remission (PR) after surgery and/or chemotherapy. During up to 21 months median following up period (range 14 to 64 months), 24 cases (62%) kept CR (median 22 months) and 4 survived with stable disease. The survival rate (SR) was 72%. Eleven cases died of relapse and disease progression. No death occurred from treatment complication. Statistical analysis showed that the age older than 18 months, and stage III and IV of the tumor were the factors predicting poor prognosis (P = 0.04 and 0.003, respectively). Patients who had the tumor originated from the retroperitoneal space, who had incomplete tumor resection, and those who did not receive ASCT had poorer prognosis, but the differences were not significant (P = 0.092, 0.55 and 0.60, respectively).

CONCLUSIONThe comprehensive protocol seemed to be reasonable. Age older than 18 months, and stage III and IV were the factors suggesting poor prognosis. The origin of the tumor, completeness of tumor resection, and use of ASCT had no significant impact on the prognosis.

Age Factors ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Chemotherapy, Adjuvant ; Child ; Child, Preschool ; Female ; Follow-Up Studies ; Hematopoietic Stem Cell Transplantation ; methods ; Humans ; Infant ; Male ; Neoplasm Recurrence, Local ; prevention & control ; surgery ; therapy ; Neoplasm Staging ; Neuroblastoma ; diagnosis ; drug therapy ; mortality ; pathology ; surgery ; therapy ; Prognosis ; Remission Induction ; methods ; Retrospective Studies ; Severity of Illness Index ; Survival Rate ; Time Factors ; Transplantation, Autologous ; methods ; Treatment Outcome