Synthetic triterpenoids inhibit growth and induce apoptosis in human glioblastoma and neuroblastoma cells through inhibition of prosurvival Akt, NF-kappaB and Notch1 signaling

Xiaohua Gao, Dorrah Deeb, Hao Jiang, Yongbo Liu, Scott A Dulchavsky, Subhash C Gautam
Journal of Neuro-oncology 2007, 84 (2): 147-57
Glioblastomas are high-risk primary brain tumors that are generally unresponsive or only weakly responsive to the currently available antineoplastic agents. Thus novel therapeutic strategies and agents are urgently needed to treat these incurable cancers. Oleanolic acid and ursolic acid are naturally occurring triterpenoids that have been used in traditional Asian medicine as anti-inflammatory and anti-cancer agents. Recently, synthetic oleanolic acid triterpenoid 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO) and its C-28 methyl ester (CDDO-Me) and C-28 imidazole (CDDO-Im) derivatives have been shown to exhibit potent antitumor activity against diverse types of tumor cell lines, including leukemia, multiple myeloma, osteosarcoma, breast, lung, and pancreatic cancer cell lines; however, the anticancer activity of these agents for brain tumors has not been reported. In the present study, we investigated the apoptosis-inducing activity of CDDOs in glioblastoma (U87MG, U251MG) and neuroblastoma (SK-N-MC) cell lines. Cell growth/viability (MTS) and cytotoxicity (LDH release) assays demonstrated that glioblastoma cell lines are least sensitive to CDDO, but are highly sensitive to CDDO-Me and CDDO-Im at concentrations of 2.5-10 muM. CDDO-Im and CDDO-Me were equipotenent in their growth inhibitory activity. The primary mode of tumor cell destruction was apoptosis as demonstrated by significant increase in the number of hypo-diploid (sub-G0) cells and annexin V-FITC binding. Induction of apoptosis was associated with the activation of procaspases-3, -8, and -9, mitochondrial depolarization and the release of cytochrome c from mitochondria. Furthermore, CDDO-Me inhibited the levels of anti-apoptotic and prosurvival p-Akt, NF-kappaB (p65) and Notch1 signaling molecules. These studies provide rationale for clinical evaluation of these novel agents for the management of lethal brain neoplasms.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"