Summary
Temozolomide (TMZ) has remained the chemotherapy of choice in patients with glioblastoma multiforme (GBM) primarily due to the lack of more effective drugs. Tumors, however, quickly develop resistance to this line of treatment creating a critical need for alternative approaches and strategies to resensitize the cells. Withaferin A (WA), a steroidal lactone derived from several genera of the Solanaceae plant family has previously demonstrated potent anti-cancer activity in multiple tumor models. Here, we examine the effects of WA against TMZ-resistant GBM cells as a monotherapy and in combination with TMZ. WA prevented GBM cell proliferation by dose-dependent G2/M cell cycle arrest and cell death through both intrinsic and extrinsic apoptotic pathways. This effect correlated with depletion of principle proteins of the Akt/mTOR and MAPK survival and proliferation pathways with diminished phosphorylation of Akt, mTOR, and p70 S6K but compensatory activation of ERK1/2. Depletion of tyrosine kinase cell surface receptors c-Met, EGFR, and Her2 was also observed. WA demonstrated induction of N-acetyl-L-cysteine-repressible oxidative stress as measured directly and through a subsequent heat shock response with HSP32 and HSP70 upregulation and decreased HSF1. Finally, pretreatment of TMZ-resistant GBM cells with WA was associated with O6-methylguanine-DNA methyltransferase (MGMT) depletion which potentiated TMZ-mediated MGMT degradation. Combination treatment with both WA and TMZ resulted in resensitization of MGMT-mediated TMZ-resistance but not resistance through mismatch repair mutations. These studies suggest great clinical potential for the utilization of WA in TMZ-resistant GBM as both a monotherapy and a resensitizer in combination with the standard chemotherapeutic agent TMZ.
Similar content being viewed by others
References
ACS (2013) Cancer facts and figures 2013. American Cancer Society, Atlanta [cited 2013 November 20]
Gillingham FJ, Yamashita J (1975) The effect of radiotherapy for glioblastoma: a review of 516 cases (author’s transl). No Shinkei Geka 3(4):329–336
Onoyama Y et al (1976) Radiation therapy in the treatment of glioblastoma. AJR Am J Roentgenol 126(3):481–492
Sheline GE (1977) Radiation therapy of brain tumors. Cancer 39(2 Suppl):873–881
Stupp R et al (2005) Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma. N Engl J Med 352(10):987–996
Stupp R et al (2002) Promising survival for patients with newly diagnosed glioblastoma multiforme treated with concomitant radiation plus temozolomide followed by adjuvant temozolomide. J Clin Oncol 20(5):1375–1382
DeAngelis LM (2005) Chemotherapy for brain tumors–a new beginning. N Engl J Med 352(10):1036–1038
Taphoorn MJ et al (2005) Health-related quality of life in patients with glioblastoma: a randomised controlled trial. Lancet Oncol 6(12):937–944
Chamberlain MC et al (2007) Early necrosis following concurrent Temodar and radiotherapy in patients with glioblastoma. J Neurooncol 82(1):81–83
Paz MF et al (2004) CpG island hypermethylation of the DNA repair enzyme methyltransferase predicts response to temozolomide in primary gliomas. Clin Cancer Res 10(15):4933–4938
Hegi ME et al (2005) MGMT gene silencing and benefit from temozolomide in glioblastoma. N Engl J Med 352(10):997–1003
Hansen RJ et al (2007) Role of O6-methylguanine-DNA methyltransferase in protecting from alkylating agent-induced toxicity and mutations in mice. Carcinogenesis 28(5):1111–1116
Kitange GJ et al (2009) Induction of MGMT expression is associated with temozolomide resistance in glioblastoma xenografts. Neuro Oncol 11(3):281–291
Quick A et al (2010) Current therapeutic paradigms in glioblastoma. Rev Recent Clin Trials 5(1):14–27
Chamberlain MC (2010) Temozolomide: therapeutic limitations in the treatment of adult high-grade gliomas. Expert Rev Neurother 10(10):1537–1544
Zhang J, Stevens MF, Bradshaw TD (2012) Temozolomide: mechanisms of action, repair and resistance. Curr Mol Pharmacol 5(1):102–114
Wen PY, Kesari S (2008) Malignant gliomas in adults. N Engl J Med 359(5):492–507
Zhang H et al (2013) Antiproliferative withanolides from Datura wrightii. J Nat Prod 76(3):445–449
Santagata S et al (2012) Using the heat-shock response to discover anticancer compounds that target protein homeostasis. ACS Chem Biol 7(2):340–349
Hahm ER et al (2011) Withaferin A-induced apoptosis in human breast cancer cells is mediated by reactive oxygen species. Plos One 6(8):e23354
Mayola E et al (2011) Withaferin A induces apoptosis in human melanoma cells through generation of reactive oxygen species and down-regulation of Bcl-2. Apoptosis 16(10):1014–1027
Widodo N et al (2010) Selective killing of cancer cells by Ashwagandha leaf extract and its component Withanone involves ROS signaling. PLoS ONE 5(10):e13536
Malik F et al (2007) Reactive oxygen species generation and mitochondrial dysfunction in the apoptotic cell death of human myeloid leukemia HL-60 cells by a dietary compound withaferin A with concomitant protection by N-acetyl cysteine. Apoptosis 12(11):2115–2133
Oh JH, Kwon TK (2009) Withaferin A inhibits tumor necrosis factor-alpha-induced expression of cell adhesion molecules by inactivation of Akt and NF-kappaB in human pulmonary epithelial cells. Int Immunopharmacol 9(5):614–619
Koduru S et al (2010) Notch-1 inhibition by Withaferin-A: a therapeutic target against colon carcinogenesis. Mol Cancer Ther 9(1):202–210
Yu Y et al (2010) Withaferin A targets heat shock protein 90 in pancreatic cancer cells. Biochem Pharmacol 79(4):542–551
Stan SD, Zeng Y, Singh SV (2008) Ayurvedic medicine constituent withaferin a causes G2 and M phase cell cycle arrest in human breast cancer cells. Nutr Cancer 60(Suppl 1):51–60
Oh JH et al (2008) Induction of apoptosis by withaferin A in human leukemia U937 cells through down-regulation of Akt phosphorylation. Apoptosis 13(12):1494–1504
Mandal C et al (2008) Withaferin A induces apoptosis by activating p38 mitogen-activated protein kinase signaling cascade in leukemic cells of lymphoid and myeloid origin through mitochondrial death cascade. Apoptosis 13(12):1450–1464
Mohan R et al (2004) Withaferin A is a potent inhibitor of angiogenesis. Angiogenesis 7(2):115–122
Singh D et al (2007) Withania somnifera inhibits NF-kappaB and AP-1 transcription factors in human peripheral blood and synovial fluid mononuclear cells. Phytother Res 21(10):905–913
Samadi AK et al (2010) A novel RET inhibitor with potent efficacy against medullary thyroid cancer in vivo. Surgery 148(6):1228–1236, discussion 1236
Shah N et al (2009) Effect of the alcoholic extract of Ashwagandha leaves and its components on proliferation, migration, and differentiation of glioblastoma cells: combinational approach for enhanced differentiation. Cancer Sci 100(9):1740–1747
Grogan PT et al (2013) Cytotoxicity of withaferin A in glioblastomas involves induction of an oxidative stress-mediated heat shock response while altering Akt/mTOR and MAPK signaling pathways. Invest New Drugs 31(3):545–557
Yang HJ, Shi GQ, Dou QP (2007) The tumor proteasome is a primary target for the natural anticancer compound withaferin a isolated from “Indian Winter Cherry”. Mol Pharmacol 71(2):426–437
Stan SD et al (2008) Withaferin A causes FOXO3a- and Bim-dependent apoptosis and inhibits growth of human breast cancer cells in vivo. Cancer Res 68(18):7661–7669
Devi PU, Kamath R, Rao BS (2000) Radiosensitization of a mouse melanoma by withaferin A: in vivo studies. Indian J Exp Biol 38(5):432–437
Samadi AK et al (2012) Natural withanolide withaferin A induces apoptosis in uveal melanoma cells by suppression of Akt and c-MET activation. Tumor Biol 33(4):1179–1189
Fong MY et al (2012) Withaferin A synergizes the therapeutic effect of doxorubicin through ROS-mediated autophagy in ovarian cancer. PLoS One 7(7):e42265
Munagala R et al (2011) Withaferin A induces p53-dependent apoptosis by repression of HPV oncogenes and upregulation of tumor suppressor proteins in human cervical cancer cells. Carcinogenesis 32(11):1697–1705
Nadkarni A et al (2012) ATM inhibitor KU-55933 increases the TMZ responsiveness of only inherently TMZ sensitive GBM cells. J Neurooncol 110(3):349–357
Samadi AK et al (2010) Withaferin A, a cytotoxic steroid from Vassobia breviflora, induces apoptosis in human head and neck squamous cell carcinoma. J Nat Prod 73(9):1476–1481
Samadi AK et al (2011) A novel C-terminal HSP90 inhibitor KU135 induces apoptosis and cell cycle arrest in melanoma cells. Cancer Lett 312(2):158–167
Ryu CH et al (2012) Valproic acid downregulates the expression of MGMT and sensitizes temozolomide-resistant glioma cells. J Biomed Biotechnol 2012:987495
Puputti M et al (2006) Amplification of KIT, PDGFRA, VEGFR2, and EGFR in gliomas. Mol Cancer Res 4(12):927–934
Wullich B et al (1993) Amplified met gene linked to double minutes in human glioblastoma. Eur J Cancer 29A(14):1991–1995
Berezowska S, Schlegel J (2011) Targeting ErbB receptors in high-grade glioma. Curr Pharm Des 17(23):2468–2487
Potti A et al (2004) Determination of HER-2/neu overexpression and clinical predictors of survival in a cohort of 347 patients with primary malignant brain tumors. Cancer Invest 22(4):537–544
Guessous F et al (2010) An orally bioavailable c-Met kinase inhibitor potently inhibits brain tumor malignancy and growth. Anticancer Agents Med Chem 10(1):28–35
Zhang WB et al (2010) Activation of AMP-activated protein kinase by temozolomide contributes to apoptosis in glioblastoma cells via p53 activation and mTORC1 inhibition. J Biol Chem 285(52):40461–40471
Ansari N, Khodagholi F, Amini M (2011) 2-Ethoxy-4,5-diphenyl-1,3-oxazine-6-one activates the Nrf2/HO-1 axis and protects against oxidative stress-induced neuronal death. Eur J Pharmacol 658(2–3):84–90
Qiao S et al (2012) Thiostrepton is an inducer of oxidative and proteotoxic stress that impairs viability of human melanoma cells but not primary melanocytes. Biochem Pharmacol 83(9):12
Khan S, Rammeloo AW, Heikkila JJ (2012) Withaferin A induces proteasome inhibition, endoplasmic reticulum stress, the heat shock response and acquisition of thermotolerance. PLoS One 7(11):e50547
D’Atri S et al (2000) Attenuation of O(6)-methylguanine-DNA methyltransferase activity and mRNA levels by cisplatin and temozolomide in jurkat cells. J Pharmacol Exp Ther 294(2):664–671
Hirose Y et al (2003) Delayed repletion of O6-methylguanine-DNA methyltransferase resulting in failure to protect the human glioblastoma cell line SF767 from temozolomide-induced cytotoxicity. J Neurosurg 98(3):591–598
Weller M et al (2011) Prolonged survival with valproic acid use in the EORTC/NCIC temozolomide trial for glioblastoma. Neurology 77(12):1156–1164
Sztajnkrycer MD (2002) Valproic acid toxicity: overview and management. J Toxicol Clin Toxicol 40(6):789–801
Baer JC et al (1993) Depletion of O6-alkylguanine-DNA alkyltransferase correlates with potentiation of temozolomide and CCNU toxicity in human tumour cells. Br J Cancer 67(6):1299–1302
Kaina B, Margison GP, Christmann M (2010) Targeting O(6)-methylguanine-DNA methyltransferase with specific inhibitors as a strategy in cancer therapy. Cell Mol Life Sci 67(21):3663–3681
Zheng M et al (2008) Interleukin-24 overcomes temozolomide resistance and enhances cell death by down-regulation of O6-methylguanine-DNA methyltransferase in human melanoma cells. Mol Cancer Ther 7(12):3842–3851
Citti L et al (1996) Targeting of O6-methylguanine-DNA methyltransferase (MGMT) activity by antimessenger oligonucleotide sensitizes CHO/Mex+ transfected cells to mitozolomide. Carcinogenesis 17(1):25–29
Kreth S et al (2013) In human glioblastomas transcript elongation by alternative polyadenylation and miRNA targeting is a potent mechanism of MGMT silencing. Acta Neuropathol 125(5):671–681
Xie SM et al (2011) Silencing of MGMT with small interference RNA reversed resistance in human BCUN-resistant glioma cell lines. Chin Med J (Engl) 124(17):2605–2610
Strik HM et al (2012) Temozolomide dosing regimens for glioma patients. Curr Neurol Neurosci Rep 12(3):286–293
Rogakou EP et al (2000) Initiation of DNA fragmentation during apoptosis induces phosphorylation of H2AX histone at serine 139. J Biol Chem 275(13):9390–9395
Grover A et al (2011) Hsp90/Cdc37 chaperone/co-chaperone complex, a novel junction anticancer target elucidated by the mode of action of herbal drug Withaferin A. BMC Bioinforma 12(Suppl 1):S30
Fu J et al (2010) Autophagy induced by valproic acid is associated with oxidative stress in glioma cell lines. Neuro-Oncology 12(4):328–340
Laurent A et al (2005) Controlling tumor growth by modulating endogenous production of reactive oxygen species. Cancer Res 65(3):948–956
Cabello CM, Bair WB 3rd, Wondrak GT (2007) Experimental therapeutics: targeting the redox Achilles heel of cancer. Curr Opin Investig Drugs 8(12):1022–1037
Lee JJ et al (2011) PTEN status switches cell fate between premature senescence and apoptosis in glioma exposed to ionizing radiation. Cell Death Differ 18(4):666–677
Koul D (2008) PTEN signaling pathways in glioblastoma. Cancer Biology & Therapy 7(9):1321–1325
Lino MM, Merlo A (2011) PI3Kinase signaling in glioblastoma. J Neurooncol 103(3):417–427
Wu J et al (2011) Vitamin K3-2,3-epoxide induction of apoptosis with activation of ROS-dependent ERK and JNK protein phosphorylation in human glioma cells. Chem Biol Interact 193(1):3–11
Acknowledgments
We would like to recognize Huaping Zhang (University of Kansas) for his preparation of WA. We would also like to thank the KUMC flow core facility for utilization of its resources established by a generous endowment from the Hall Foundation and by NIH Grant Number P20 RR016443 from the COBRE program of the National Center for Research Resources. We are thankful for research support provided by the Departments of Surgery at the University of Kansas Medical Center and University of Michigan as well as the University of Michigan Comprehensive Cancer Center.
Conflict of interest
None related to this work.
Role of funding sources
This work was made possible by support from the National Institutes of Health (NIH-COBRE P20 RR015563 P.I. B. Timmermann), the Institute for Advancing Medical Innovation (PI: MS Cohen), a University of Kansas Cancer Center Summer Student Training Program grant (PT Grogan), the Departments of Surgery at the University of Kansas Medical Center and University of Michigan (MS Cohen), and a University of Michigan Comprehensive Cancer Center CCSG Development award (PI: MS Cohen).
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Online Resource 1
WA treatment resulted in depletion of total protein levels in both AMPKα and TSC2 at 24-48h in both U251TMZ and U87TMZ cells. U87TMZ cells also demonstrated reduced phosphorylation of AMPKα in contrast to previous findings in U87 parental cells. U251TMZ cells display dose-dependent activating phosphorylation of AMPKα and downstream TSC2. (PPT 402 kb)
Online Resource 2
(a) 24h WA pretreatment did not prevent TMZ efficacy in TMZ-sensitive U251 and U87 parental cells as assessed by a normalized MTS assay, suggesting a lack of inhibition of functional MMR. In U251 cells, WA mildly sensitized cells to TMZ, but no sensitization was observed in U87 cells. (b) Given a described oxidative component of TMZ therapy through activation of AMPKα, markers of oxidation were assessed during combination therapy of WA and TMZ in TMZ-resistant cells. HSP32 and HSP70, known to be upregulated in response to oxidative stress, increased with WA treatment to a maximal level but were not further modulated by the presence of TMZ. Treatment with TMZ only resulted in elevated p-AMPKα in only U138 cells, but WA failed to further increase this phosphorylation in combination with TMZ. This was confirmed downstream by failure to further inhibit mTOR activation with combination therapy, suggesting efficacy of such treatment was not due to potentiated or synergized elevation in oxidation status. **p < 0.01 (PPT 791 kb)
Rights and permissions
About this article
Cite this article
Grogan, P.T., Sarkaria, J.N., Timmermann, B.N. et al. Oxidative cytotoxic agent withaferin A resensitizes temozolomide-resistant glioblastomas via MGMT depletion and induces apoptosis through Akt/mTOR pathway inhibitory modulation. Invest New Drugs 32, 604–617 (2014). https://doi.org/10.1007/s10637-014-0084-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10637-014-0084-7