ABSTRACT
AIM: To investigate the activity of interleukin-1? converting enzyme in transplanted intracerebral rat gliomas under angiotensin II-induced hypertension chemotherapy. METHODS: The brain tumor model was produced in Wistar rats by stereotaxic inoculation of C6 glioma cells (1?10 12 /L). Tumor-bearing rats were treated with carmustine, teniposide and lisplatin (chemotherapy) during angiotensin II-induced hypertension. Then, the survival time of tumor-bearing rats, tumor blood flow, the concentration of drug, volume of gliomas and the activity of interleukin-1? converting enzyme in glioma were examined.RESULTS: The survival time of tumor-bearing rats was significantly longer in chemotherapy with angiotensin II-induced hypertension group than that of chemotherapy alone. In addition, regional tumor blood flow, the concentration of chemotherapeutic drug and the activity of interleukin-1? converting enzyme in transplanted rat gliomas were increased, while the volume of gliomas was decreased in hypertention chemotherapy group compared with chemotherapy alone. CONCLUSION: Chemotherapy with angiotensin II-induced hypertension has a enhancing effect on chemotherapy for improving the drug delivery to tumor tissue by a increased tumor blood flow and enhancing activity of interleukin-1? converting enzyme.
ABSTRACT
Objective To investigate whether interleukin 18 (IL 18) and IL 1? converting enzyme (ICE, caspase 1) is expressed in islet ? cells and the mechanism of their expression control. Methods Rat insulinoma (RIN) cells, FACS purified rat ? cells, isolated rat islets, and islets isolated from interferon regulatory factor 1 (IRF 1) gene knockout mice were incubated with or without cytokines. Reverse transcription polymerase chain reaction (RT PCR) was used to quantitate IL 18 and caspase 1 mRNA expression. IL 18 protein expression was detected by using Western blot. Results (1)Interferon ? (IFN ?) increased IL 18 mRNA expression in RIN cells, purified rat ? cells, and intact rat islets, and the effect was unchanged in IRF 1 knockout mouse islets. (2) IFN ? highly up regulated caspase 1 mRNA expression in RIN cells and intact rat islets, but the expression was abolished in IRF 1 knockout mouse islets. (3) IL 18 protein was undetectable in lysates and supernatants of RIN cells. Conclusion IFN ? up regulates IL 18 and caspase 1 expression in islet ? cells. IL 18 expression is not dependent on a transcription factor IRF 1, while caspase 1 expression is in an IRF 1 dependent way.