Curcumin suppresses growth and chemoresistance of human glioblastoma cells via AP-1 and NFkappaB transcription factors.
Malignant gliomas are a debilitating class of brain tumors that are resistant to radiation and chemotherapeutic drugs, contributing to the poor prognosis associated with these tumors. Over-expression of transcription factors such as NFkappaB and AP-1 contribute to the enhanced glioma survival, radioresistance, and chemoresistance. Curcumin, which may inhibit these pathways, was therefore investigated for a potential therapeutic role in glioma. The effect of curcumin on glioma survival was investigated in human (T98G, U87MG, and T67) and rat (C6) glioma cell lines. The ability of curcumin to overcome glioma cell radioresistance and chemoresistance was also explored. Curcumin reduced cell survival in a p53- and caspase-independent manner, an effect correlated with the inhibition of AP-1 and NFkappaB signaling pathways via prevention of constitutive JNK and Akt activation. Curcumin-sensitized glioma cells to several clinically utilized chemotherapeutic agents (cisplatin, etoposide, camptothecin, and doxorubicin) and radiation, effects correlated with reduced expression of bcl-2 and IAP family members as well as DNA repair enzymes (MGMT, DNA-PK, Ku70, Ku80, and ERCC-1). These findings support a role for curcumin as an adjunct to traditional chemotherapy and radiation in the treatment of brain cancer.
Dhandapani
Krishnan M
KM
Department of Neurosurgery, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, Georgia 30912, USA. kdhandapani@mcg.edu
Mahesh
Virendra B
VB
Brann
Darrell W
DW
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D003474:Curcumin / Q000494:pharmacology* / Q000627:therapeutic use; D004260:DNA Repair / Q000187:drug effects / Q000502:physiology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects* / Q000502:physiology; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000502:physiology; D005909:Glioblastoma / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism; D016328:NF-kappa B / Q000187:drug effects / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D018808:Transcription Factor AP-1 / Q000187:drug effects / Q000378:metabolism; D015533:Transcriptional Activation / Q000187:drug effects / Q000502:physiology; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000378:metabolism
D000970:Antineoplastic Agents; D016328:NF-kappa B; D018808:Transcription Factor AP-1; D016159:Tumor Suppressor Protein p53; D051057:Proto-Oncogene Proteins c-akt; D048031:JNK Mitogen-Activated Protein Kinases; D020169:Caspases; D003474:Curcumin