title: Lobarstin enhances chemosensitivity in human glioblastoma T98G cells.
abstract: OBJECTIVE
  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.
  
  
  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, O(6)-methylguanine-DNA methyltransferase, poly(ADP-ribose) polymerase 1 and ligase 3 were reduced in lobarstin-treated cells.
  
  
  CONCLUSIONS
  Enhanced sensitivity to temozolomide by lobarstin co-treatment may be attributed to reduced DNA repair.
authors: Department of Pathology, College of Medicine, Hanyang University, 222 Wangsimni-ro, Seondong-gu, Seoul, 133-791, Republic of Korea. hc2n@hanyang.ac.kr.
authors: Sojin
authors: S
authors: Kim
authors: Sungsin
authors: S
authors: Jo
authors: Hongki
authors: H
authors: Lee
authors: Tae Ue
authors: TU
authors: Kim
authors: Il-Chan
authors: IC
authors: Kim
authors: Joung Han
authors: JH
authors: Yim
authors: Heekyoung
authors: H
authors: Chung
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001483:Base Sequence; D001572:Benzofurans / Q000494:pharmacology*; D001932:Brain Neoplasms / Q000201:enzymology / Q000473:pathology*; D045744:Cell Line, Tumor; D020552:Comet Assay; D004249:DNA Damage; D017931:DNA Primers; D004260:DNA Repair / Q000235:genetics; D003606:Dacarbazine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004357:Drug Synergism; D005909:Glioblastoma / Q000201:enzymology / Q000473:pathology*; D006801:Humans; D062385:Hydroxybenzoates / Q000494:pharmacology*; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077204:Temozolomide
chemical_list: D000970:Antineoplastic Agents; D001572:Benzofurans; D017931:DNA Primers; D062385:Hydroxybenzoates; C586544:lobarstin; D003606:Dacarbazine; D019853:O(6)-Methylguanine-DNA Methyltransferase; D000077204:Temozolomide
keywords: DNA repair; Lobarstin; chemosensitivity; glioblastoma; temozolomide