ABSTRACT
OBJECTIVE: The authors present two polymers as carriers of anti-neoplastic agents for intratumoral chemotherapy. We investigated in vitro tumor cytotoxicity againt C6 glioma cells with 20ul cis-platinum (CDDP)-polymer. METHODS: We firstly developed new two thermosensitive sol-gel reVersible polymer (poly-2 and poly-6) by random copolyerization from ethylene glycol and caprolactone polymer that is sol state over 50degrees C but changed gradually to gel less than 50degrees C We evaluated the time-related release profiles of 10mg cisplatin from CDDP-Poly 2 and CDDP-Poly 6 in 25ml of pH 7.4 phosphate buffer saline using UV spectrophotometer during 31days. We cultured C6 glioma cell line in 10cm round plates for 2 days and added 20microliter of CDDP-polymer containing 30uM of CDDP into the center of each plate. We counted C6 cell number every 12 hours for 72 hours at same 3 sites of each 6 well plates. RESULTS: UV spevtrophotometry showed total 12.6% of CDDP released from CDDP-poly 2 and total 56.9% of CDDP from CDDP-poly 6 on 31 days. Both carrier polymer showed total released amount of CDDP directly correlated with time without initial dumping effect. The CDDP released from 20microliter of CDDP-poly 2 and CDDP-poly 6 in 48 hours showed cytotoxicity to C6 glioma cells more than 50% in vitro cell culture system. CONCLUSION: This results suggest that less than 20microliter CDDP-polymer could be applied in vivo brain tumor model to show significant cytotoxicity.