TY - JOUR T1 - Lobarstin Enhances Chemosensitivity in Human Glioblastoma T98G Cells JF - Anticancer Research JO - Anticancer Res SP - 5445 LP - 5451 VL - 33 IS - 12 AU - SOJIN KIM AU - SUNGSIN JO AU - HONGKI LEE AU - TAE UE KIM AU - IL-CHAN KIM AU - JOUNG HAN YIM AU - HEEKYOUNG CHUNG Y1 - 2013/12/01 UR - http://ar.iiarjournals.org/content/33/12/5445.abstract N2 - Background/Aim: Lobarstin is a metabolite occurring from the Antarctic lichen Stereocaulon alpnum. Human glioblastoma is highly resistant to chemotherapy with temozolomide. Lobarstin was examined for its effect on glioblastoma. Materials and Methods: Temozolomide-resistant T98G cells were subjected to toxicity test with temozolomide and/or lobarstin. DNA damage and recovery was assessed by the alkaline comet assay and expression of DNA repair genes was examined by RT-PCR and western blot analysis. Results: Lobarstin alone at 40 μM was toxic against T98G, but had no effect in primary human fibroblasts. Co-treatment of lobarstin with temozolomide yielded enhanced toxicity. Temozolomide-alone or with lobarstin co-treatment gave similar extent of DNA damage. However, the recovery was reduced in co-treated cells. Expression of DNA repair genes, O6-methylguanine-DNA methyltransferase, poly(ADP-ribose) polymerase 1 and ligase 3 were reduced in lobarstin-treated cells. Conclusion: Enhanced sensitivity to temozolomide by lobarstin co-treatment may be attributed to reduced DNA repair. ER -