Objective: To study the vaccine potency of gene-modified tumor cells, we have constructed IL-12, H7-1 and GM-CSF express vector using retrovirus. Methods: It was transfected into EL-4 thymic lylmphoma cells respectively and the effect of gene transduction on anti-tumor immunity were investigated. Results: The tumorigenicity of EL-4/IL-12 transfectant in C57BI/6 syn- ergistical mice was decreased significantly after implanted with EL-4/IL-12 transfectant compaired with EL-4/Wt or EL-4/Neo groups (P

In order to study the vaccine potency of gene-modified tumor cells, IL-12 express vector was constructed by using retrovirus. The vector was transfected into EL-4 thymic lymphoma cells and the effect of transfectant on anti-tumor immunity was investigated. The tumorigenicity of EL-4/IL-12 transfectant in syngeneic C57BL/6 mice was decreased significantly after implanted with EL-4/IL-12 transfectant compared with EL-4/Wt or EL-4/Neo groups (P < 0.001). The systemic protective immunity was induced against the challenge with EL-4/Wt (in 8/10 mice) after the rejection of EL-4/IL-12 in vivo experiment, a stronger CTL activity against EL-4/Wt cells and a weak killer activity against syngeneic Lewis lung carcinoma (LLC) cells were obtained in (51)Cr release assay. In vivo depletion analysis suggested that the decreased tumorigenicity mainly depended on CD4(+), CD8(+) and NK cells. Therapeutic vaccines with EL-4/IL-12 cells could retard the growth of established EL-4/Wt tumors significantly compared with those of EL-4/Neo (P < 0.005). These studies suggested that immunotherapy and gene therapy using IL-12 is effective in hematopoietic malignancy and IL-12 has prospects of application in human cancer treatment in the near future.

Tumor lysis syndrome (TLS) is a metabolic disorder that is caused by acute lysis of massive tumor cells. We report a case with opioids-related severe respiratory depression induced by TLS. A 39-year-old man received chemotherapy for mycosis fungoides. Two hours after administration of chemotherapeutic agents, his renal function worsened, and he was diagnosed with TLS by laboratory and clinical findings. Moreover, he showed severe respiratory depression and pinpoint pupils, and become drowsy. These symptoms were attributed to oxycodone that had been administered to treat his tumor-related cutaneous pain, and were improved by injection of anti-opioids agent naloxone. In this case, we consider that the clearance of oxycodone was disrupted by renal dysfunction caused by TLS, leading to enhancement of the effects of oxycodone.