Planta Med 2015; 81(14): 1223-1239
DOI: 10.1055/s-0035-1546251
Reviews
Georg Thieme Verlag KG Stuttgart · New York

Hsp90 Activity Modulation by Plant Secondary Metabolites

Fabrizio Dal Piaz
1   Dipartimento di Farmacia, Università di Salerno, Fisciano (SA), Italy
,
Stefania Terracciano
1   Dipartimento di Farmacia, Università di Salerno, Fisciano (SA), Italy
,
Nunziatina De Tommasi
1   Dipartimento di Farmacia, Università di Salerno, Fisciano (SA), Italy
,
Alessandra Braca
2   Dipartimento di Farmacia, Università di Pisa, Pisa, Italy
› Author Affiliations
Further Information

Publication History

received 30 December 2014
revised 13 May 2015

accepted 30 May 2015

Publication Date:
30 July 2015 (online)

Abstract

Hsp90 is an evolutionarily conserved adenosine triphosphate-dependent molecular chaperone and is one of the most abundant proteins in the cells (1–3 %). Hsp90 is induced when a cell undergoes various types of environmental stresses such as heat, cold, or oxygen deprivation. It is involved in the turnover, trafficking, and activity of client proteins, including apoptotic factors, protein kinases, transcription factors, signaling proteins, and a number of oncoproteins. Most of the Hsp90 client proteins are involved in cell growth, differentiation, and survival, and include kinases, nuclear hormone receptors, transcription factors, and other proteins associated with almost all the hallmarks of cancer. Consistent with these diverse activities, genetic and biochemical studies have demonstrated the implication of Hsp90 in a range of diseases, including cancer, making this chaperone an interesting target for drug research.

During the last few decades, plant secondary metabolites have been studied as a major source for lead compounds in drug discovery. Recently, several plant-derived small molecules have been discovered exhibiting inhibitory activity towards Hsp90, such as epigallocatechin gallate, gedunin, lentiginosine, celastrol, and deguelin. In this work, an overview of plant secondary metabolites interfering with Hsp90 activities is provided.

 
  • References

  • 1 Zhang H, Burrows F. Targeting multiple signal transduction pathways through inhibition of Hsp90. J Mol Med 2004; 82: 488-499
  • 2 Whitesell L, Lindquist SL. Hsp90 and the chaperoning of cancer. Nat Rev Cancer 2005; 5: 761-772
  • 3 Pearl LH, Prodromou C. Structure and in vivo function of Hsp90. Curr Opin Struct Biol 2000; 10: 46-51
  • 4 Patki JM, Pawar SS. Hsp90: chaperone-me-not. Pathol Oncol Res 2013; 19: 631-640
  • 5 Scheibel T, Buchner J. The Hsp90 complex-a super-chaperone machine as a novel drug target. Biochem Pharmacol 1998; 56: 675-682
  • 6 Solit DB, Rosen N. Hsp90: a novel target for cancer therapy. Curr Top Med Chem 2006; 6: 1205-1214
  • 7 Holzbeierlein JM, Windsperger A, Vielhauer G. Hsp90: a drug target?. Curr Oncol Rep 2010; 12: 95-101
  • 8 Jego G, Hazoume A, Seigneuric R, Garrido C. Targeting heat shock proteins in cancer. Cancer Lett 2013; 332: 275-285
  • 9 Neckers L, Workman P. Hsp90 molecular chaperone inhibitors: are we there yet?. Clin Cancer Res 2012; 18: 64-76
  • 10 Bhat R, Tummalapalli SR, Rotella DP. Progress in the discovery and development of heat shock protein 90 (Hsp90) inhibitors. J Med Chem 2014; 57: 8718-8728
  • 11 Carlson EE. Natural products as chemical probes. ACS Chem Biol 2010; 5: 639-653
  • 12 Neckers L. Chaperoning oncogenes: Hsp90 as a target of geldanamycin. Handb Exp Pharmacol 2006; 172: 259-277
  • 13 Jhaveri K, Ochiana SO, Dunphy MP, Gerecitano JF, Corben AD, Peter RI, Janjigian YY, Gomes-DaGama EM, Koren 3rd J, Modi S, Chiosis G. Heat shock protein 90 inhibitors in the treatment of cancer: current status and future directions. Expert Opin Investig Drugs 2014; 23: 611-628
  • 14 Patel D, Shukla S, Gupta S. Apigenin and cancer chemoprevention: progress, potential and promise (review). Int J Oncol 2007; 30: 233-245
  • 15 Shukla S, Gupta S. Apigenin: a promising molecule for cancer prevention. Pharm Res 2010; 27: 962-978
  • 16 Simons AL, Renouf M, Hendrich S, Murphy PA. Human gut microbial degradation of flavonoids: structure-function relationships. J Agric Food Chem 2005; 53: 4258-4263
  • 17 Tang D, Yu Y, Zheng X, Wu J, Li Y, Wu X, Du Q, Yin X. Comparative investigation of in vitro biotransformation of 14 components in Ginkgo biloba extract in normal, diabetes and diabetic nephropathy rat intestinal bacteria matrix. J Pharm Biomed Anal 2014; 100: 1-10
  • 18 Osada M, Imaoka S, Funae Y. Apigenin suppresses the expression of VEGF, an important factor for angiogenesis, in endothelial cells via degradation of HIF-1α protein. FEBS Lett 2004; 575: 59-63
  • 19 Zhao M, Ma J, Zhu HY, Zhang XH, Du ZY, Xu YJ, Yu XD. Apigenin inhibits proliferation and induces apoptosis in human multiple myeloma cells through targeting the trinity of CK2, Cdc37 and Hsp90. Mol Cancer 2011; 10: 104
  • 20 Miski M, Ulubelen A, Johansson C, Mabry TJ. Antibacterial activity studies of flavonoids from Salvia palaestina . J Nat Prod 1983; 46: 874-875
  • 21 Wolfman C, Viola H, Paladini A, Dajas F, Medina JH. Possible anxiolytic effects of chrysin, a central benzodiazepine receptor ligand isolated from Passiflora coerulea . Pharmacol Biochem Behav 1994; 47: 1-4
  • 22 Brown E, Hurd NS, McCall S, Ceremuga TE. Evaluation of the anxiolytic effects of chrysin, a Passiflora incarnata extract, in the laboratory rat. AANA J 2007; 75: 333-337
  • 23 Lapidot T, Walker MD, Kanner J. Antioxidant and prooxidant effects of phenolics on pancreatic β-cells in vitro . J Agric Food Chem 2002; 50: 7220-7250
  • 24 Cho H, Yun CW, Park WK, Kong JY, Kim KS, Park Y, Lee S, Kim BK. Modulation of the activity of pro-inflammatory enzymes, COX-2 and iNOS, by chrysin derivatives. Pharmacol Res 2004; 49: 37-43
  • 25 Fu B, Xue J, Li Z, Shi X, Jiang BH, Fang J. Chrysin inhibits expression of hypoxia-inducible factor-1α through reducing hypoxia-inducible factor-1α stability and inhibiting its protein synthesis. Mol Cancer Ther 2007; 6: 220-226
  • 26 Seo HJ, Surh YJ. Eupatilin, a pharmacologically active flavone derived from Artemisia plants, induces apoptosis in human promyelocytic leukemia cells. Mutat Res 2001; 496: 191-198
  • 27 Kim JM, Lee DH, Kim JS, Lee JY, Park HG, Kim YJ, Oh YK, Jung HC, Kim SI. 5,7-dihydroxy-3,4,6-trimethoxyflavone inhibits the inflammatory effects induced by Bacteroides fragilis enterotoxin via dissociating the complex of heat shock protein 90 and IkBα and IkB kinase-γ in intestinal epithelial cell culture. Clin Exp Immunol 2009; 155: 541-551
  • 28 Gábor M. Anti-inflammatory and anti-allergic properties of flavonoids. Prog Clin Biol Res 1986; 213: 471-480
  • 29 Seelinger G, Merfort I, Schempp CM. Antioxidant, anti-inflammatory and anti-allergic activities of luteolin. Planta Med 2008; 74: 1667-1677
  • 30 Seelinger G, Merfort I, Wölfle U, Schempp CM. Anti-carcinogenic effects of the flavonoid luteolin. Molecules 2008; 13: 2628-2651
  • 31 Serra A, Macià A, Romero MP, Reguant J, Ortega N, Motilva MJ. Metabolic pathways of the colonic metabolism of flavonoids (flavonols, flavones and flavanones) and phenolic acids. Food Chem 2012; 130: 383-393
  • 32 Chen C YC, Chen GW, Chen WYC. Molecular simulation of HER2/neu degradation by inhibiting Hsp90. J Chin Chem Soc 2008; 55: 297-302
  • 33 Fu J, Chen D, Zhao B, Zhao Z, Zhou J, Xu Y, Xin Y, Liu C, Luo L, Yin Z. Luteolin induces carcinoma cell apoptosis through binding Hsp90 to suppress constitutive activation of STAT3. PLoS One 2012; 7: e49194
  • 34 Hong Z, Cao X, Li N, Zhang Y, Lan L, Zhou Y, Pan X, Shen L, Yin Z, Luo L. Luteolin is effective in the non-small cell lung cancer model with L858R/T790 M EGF receptor mutation and erlotinib resistance. Br J Pharmacol 2014; 171: 2842-2853
  • 35 Chen D, Bi A, Dong X, Jiang Y, Rui B, Liu J, Yin Z, Luo L. Luteolin exhibits anti-inflammatory effects by blocking the activity of heat shock protein 90 in macrophages. Biochem Biophys Res Commun 2014; 443: 326-332
  • 36 Alfonso D, Kapetanidis I. Flavonoids from Iochroma gesnerioides . Pharm Acta Helv 1994; 68: 211-214
  • 37 Tamura M, Hirayama K, Itoh K. Role of intestinal flora on the metabolism, absorption, and biological activity of dietary flavonoids. Bioscience Microflora 2003; 22: 125-131
  • 38 Middleton jr. E, Kandaswami C. Effects of flavonoids on immune and inflammatory cell functions. Biochem Pharmacol 1992; 43: 1167-1179
  • 39 Wang HK. The therapeutic potential of flavonoids. Expert Opin Investig Drugs 2000; 9: 2103-2119
  • 40 Dechsupa S, Kothan S, Vergote J, Leger G, Martineau A, Beranger S, Kosanlavit R, Moretti JL, Mankhetkorn S. Quercetin, Siamois 1 and Siamois 2 induce apoptosis in human breast cancer MDA-MB-435 cells xenograft in vivo . Cancer Biol Ther 2007; 6: 56-61
  • 41 Davies SP, Reddy H, Caivano M, Cohen P. Specificity and mechanism of action of some commonly used protein kinase inhibitors. Biochem J 2000; 351: 95-105
  • 42 Harwood M, Danielewska-Nikiel B, Borzelleca JF, Flamm GW, Williams GM, Lines TC. A critical review of the data related to the safety of quercetin and lack of evidence of in vivo toxicity, including lack of genotoxic/carcinogenic properties. Food Chem Toxicol 2007; 45: 2179-2205
  • 43 Nagai N, Nakai A, Nagata K. Quercetin suppresses heat shock response by down regulation of HSF1. Biochem Biophys Res Commun 1995; 208: 1099-1105
  • 44 Aalinkeel R, Bindukumar B, Reynolds JL, Sykes DE, Mahajan SD, Chadha KC, Schwartz SA. The dietary bioflavonoid, quercetin, selectively induces apoptosis of prostate cancer cells by down-regulating the expression of heat shock protein 90. Prostate 2008; 68: 1773-1789
  • 45 Wang RE, Hunt CR, Chen J, Taylor JS. Biotinylated quercetin as an intrinsic photoaffinity proteomics probe for the identification of quercetin target proteins. Bioorg Med Chem 2011; 19: 4710-4720
  • 46 Jeong JH, An JY, Kwon YT, Li LY, Lee YJ. Quercetin-induced ubiquitination and down regulation of Her-2/neu. J Cell Biochem 2008; 105: 585-595
  • 47 East AJ, Ollis WD, Wheeler RE. Natural occurrence of 3-aryl-4-hydroxycoumarins. Part I. Phytochemical examination of Derris robusta (roxb) benth. J Chem Soc C 1969; 3: 365-373
  • 48 Hadden MK, Galam L, Gestwicki JE, Matts RL, Blagg BSJ. Derrubone, an inhibitor of the Hsp90 protein folding machinery. J Nat Prod 2007; 70: 2014-2018
  • 49 Li Y, Zhang T, Schwartz SJ, Sun D. New developments in Hsp90 inhibitors as anticancer therapeutics: mechanisms, clinical perspective and more potential. Drug Resist Updat 2009; 12: 17-27
  • 50 El Hamidieh A, Grammatikakis N, Patsavoudi E. Cell surface Cdc37 participates in extracellular Hsp90 mediated cancer cell invasion. PLoS One 2012; 7: 1-9
  • 51 Özgür A, Tutar Y. Heat shock protein 90 inhibitors in oncology. Curr Proteomics 2014; 11: 2-16
  • 52 Hastings JM, Hadden MK, Blagg BS. Synthesis and evaluation of derrubone and select analogues. J Org Chem 2008; 73: 369-373
  • 53 Mays JR, Hill SA, Moyers JT, Blagg BS. The synthesis and evaluation of flavone and isoflavone chimeras of novobiocin and derrubone. Bioorg Med Chem 2010; 18: 249-266
  • 54 Khalid S, Paul S. Identifying a C-terminal ATP binding sites-based novel Hsp90-inhibitor in silico: a plausible therapeutic approach in Alzheimerʼs disease. Med Hypotheses 2014; 83: 39-46
  • 55 Roux DG, Paulus E. Condensed tannins. 10. Isolation of (−)-butin and butein from wattle heartwoods. Biochem J 1961; 80: 62-63
  • 56 Wang Z, Lee Y, Eun JS, Bae EJ. Inhibition of adipocyte inflammation and macrophage chemotaxis by butein. Eur J Pharmacol 2014; 738: 40-48
  • 57 Lee SH, Seo GS, Sohn DH. Inhibition of lipopolysaccharide-induced expression of inducible nitricoxide synthase by butein in RAW264.7 cells. Biochem Biophys Res Commun 2004; 323: 125-132
  • 58 Lee SH, Nan JX, Zhao YZ, Woo SW, Park EJ, Kang TH, Seo GS, Kim YC, Sohn DH. Thechalcone butein from Rhus verniciflua shows anti-fibrogenic activity. Planta Med 2003; 69: 990-994
  • 59 Pandey MK, Sandur SK, Sung B, Sethi G, Kunnumakkara AB, Aggarwal BB. Butein, a tetrahydroxychalcone, inhibits nuclear factor (NF)-kappaB and NF-kappaB-regulated gene expression through direct inhibition of IkappaBalpha kinase beta on cysteine 179 residue. J Biol Chem 2007; 282: 17340-17350
  • 60 Chua AW, Hay HS, Rajendran P, Shanmugam MK, Li F, Bist P, Koay ES, Lim LH, Kumar AP, Sethi G. Butein downregulates chemokine receptor CXCR4 expression and function through suppression of NF-κB activation in breast and pancreatic tumor cells. Biochem Pharmacol 2010; 80: 1553-1562
  • 61 Lau GT, Huang H, Lin SM, Leung LK. Butein downregulates phorbol 12-myristate 13-acetate-induced COX-2 transcriptional activity in cancerous and non-cancerous breast cells. Eur J Pharmacol 2010; 648: 24-30
  • 62 Rajendran P, Ong TH, Chen L, Li F, Shanmugam MK, Vali S, Abbasi T, Kapoor S, Sharma A, Kumar AP, Hui KM, Sethi G. Suppression of signal transducer and activator of transcription 3 activation by butein inhibits growth of human hepatocellular carcinoma in vivo . Clin Cancer Res 2011; 17: 1425-1439
  • 63 Seo YH. Butein disrupts Hsp90′s molecular chaperoning function and exhibits anti-proliferative effects against drug-resistant cancer cells. Bull Korean Chem Soc 2013; 34: 3345-3349
  • 64 Seo YH, Jeong JH. Synthesis of butein analogues and their anti-proliferative activity against gefitinib-resistant non-small cell lung cancer (NSCLC) through Hsp90 inhibition. Bull Korean Chem Soc 2014; 35: 1294-1298
  • 65 Kuo YF, Su YZ, Tseng YH, Wang SY, Wang HM, Chueh PJ. Flavokawain B, a novel chalcone from Alpinia pricei Hayata with potent apoptotic activity: involvement of ROS and GADD153 upstream of mitochondria-dependent apoptosis in HCT116 cells. Free Radic Biol Med 2010; 49: 214-226
  • 66 Henderson BE, Kolonel LN, Dworsky R, Kerford D, Mori E, Singh K, Thevenot H. Cancer incidence in the islands of the Pacific. Natl Cancer Inst Monogr 1985; 69: 73-81
  • 67 Steiner GG. The correlation between cancer incidence and kava consumption. Hawaii Med J 2000; 59: 420-422
  • 68 Warmka JK, Solberg EL, Zeliadt NA, Srinivasan B, Charlson AT, Xing C, Wattenberg EV. Inhibition of mitogen activated protein kinases increases the sensitivity of A549 lung cancer cells to the cytotoxicity induced by a kava chalcone analog. Biochem Biophys Res Commun 2012; 424: 488-492
  • 69 Sakai T, Eskander RN, Guo Y, Kim KJ, Mefford J, Hopkins J, Bhatia NN, Zi X, Hoang BH. Flavokawain B, a kava chalcone, induces apoptosis in synovial sarcoma cell lines. J Orthop Res 2012; 30: 1045-1050
  • 70 Lin E, Lin WH, Wang SY, Chen CS, Liao JW, Chang HW, Chen SC, Lin KY, Wang L, Yang HL, Hseu YC. Flavokawain B inhibits growth of human squamous carcinoma cells: involvement of apoptosis and cell cycle dysregulation in vitro and in vivo . J Nutr Biochem 2012; 23: 368-378
  • 71 Li X, Liu Z, Xu X, Blair CA, Sun Z, Xie J, Lilly MB, Zi X. Kava components down-regulate expression of AR and AR splice variants and reduce growth in patient-derived prostate cancer xenografts in mice. PLoS One 2012; 7: e31213
  • 72 Ji T, Lin C, Krill LS, Eskander R, Guo Y, Zi X, Hoang BH. Flavokawain B, a kava chalcone, inhibits growth of human osteosarcoma cells through G2/M cell cycle arrest and apoptosis. Mol Cancer 2013; 12: 55
  • 73 Seo YH, Oh YJ. Synthesis of flavokawain B and its anti-proliferative activity against gefitinib-resistant non-small cell lung cancer (NSCLC). Bull Korean Chem Soc 2013; 34: 3782-3786
  • 74 Shibata S. A drug over the millennia: pharmacognosy, chemistry, and pharmacology of licorice. Yakugaku Zasshi 2000; 120: 849-862
  • 75 Hatano T, Kagawa H, Yasuhara T, Okuda T. Two new flavonoids and other constituents in licorice root: their relative astringency and radical scavenging effects. Chem Pharm Bull (Tokyo) 1988; 36: 2090-2097
  • 76 Fu Y, Hsieh TC, Guo J, Kunicki J, Lee MY, Darzynkiewicz Z, Wu JM. Licochalcone-A, a novel flavonoid isolated from licorice root (Glycyrrhiza glabra), causes G2 and late-G1 arrests in androgen-independent PC-3 prostate cancer cells. Biochem Biophys Res Commun 2004; 322: 263-270
  • 77 Xiao XY, Hao M, Yang XY, Ba Q, Li M, Ni S J, Wang LS, Du X. Licochalcone A inhibits growth of gastric cancer cells by arresting cell cycle progression and inducing apoptosis. Cancer Lett 2011; 1: 69-75
  • 78 Chu X, Ci X, Wei M, Yang X, Cao Q, Guan M, Li H, Deng Y, Feng H, Deng X. Licochalcone A inhibits lipopolysaccharide-induced inflammatory response in vitro and in vivo . J Agric Food Chem 2012; 60: 3947-3954
  • 79 Landis-Piwowar KR, Huo C, Chen D, Milacic V, Shi G, Chan TH, Dou QP. A novel prodrug of the green tea polyphenol (−)-epigallocatechin-3-gallate as a potential anticancer agent. Cancer Res 2007; 67: 4303-4310
  • 80 Palermo CM, Westlake CA, Gasiewicz TA. Epigallocatechin gallate inhibits aryl hydrocarbon receptor gene transcription through an indirect mechanism involving binding to a 90 KDa heat shock protein. Biochemistry 2005; 44: 5041-5052
  • 81 Yin Z, Henry EC, Gasiewicz TA. (−)-Epigallocatechin-3-gallate is a novel Hsp90 inhibitor. Biochemistry 2009; 48: 336-345
  • 82 Li Y, Zhang T, Jiang Y, Lee HF, Schwartz SJ, Sun D. (−)-Epigallocatechin-3-gallate inhibits Hsp90 function by impairing Hsp90 association with cochaperones in pancreatic cancer cell line Mia Paca-2. Mol Pharm 2009; 6: 1152-1159
  • 83 Tran PL, Kim SA, Choi HS, Yoon JH, Ahn SG. Epigallocatechin-3-gallate suppresses the expression of Hsp70 and Hsp90 and exhibits antitumor activity in vitro and in vivo . BMC Cancer 2010; 10: 276
  • 84 Khan N, Afaq F, Saleem M, Ahmad N, Mukhtar H. Targeting multiple signalling pathways by green tea polyphenol (−)-epigallocatechin-3-gallate. Cancer Res 2006; 66: 2500-2505
  • 85 Li M, He Z, Ermakova S, Zheng D, Tang F, Cho YY, Zhu F, Ma WY, Sham Y, Rogozin EA, Bode AM, Cao Y, Dong Z. Direct inhibition of insulin-like growth factor-I receptor kinase activity by (−)-epigallocatechin-3-gallate regulates cell transformation. Cancer Epidemiol Biomarkers Prev 2007; 16: 598-605
  • 86 Ramirez-Sanchez I, Aguilar U, Ceballos G, Villarreal F. (−)-Epicatechin-induced calcium independent eNOS activation: roles of Hsp90 and AKT. Mol Cell Biochem 2012; 370: 141-150
  • 87 Halder B, Das Gupta S, Gomes A. Black tea polyphenols induce human leukemic cell cycle arrest by inhibiting Akt signalling. Possible involvement of Hsp90, Wnt/β-catenin signalling and FOXO1. FEBS J 2012; 279: 2876-2891
  • 88 Malafronte N, Vassallo A, Dal Piaz F, Bader A, Braca A, De Tommasi N. Biflavonoids from Daphne linearifolia Hart. Phytochemistry Lett 2012; 5: 621-625
  • 89 Marcu MG, Chadli A, Bouhouche I, Catelli M, Neckers LM. The heat shock protein 90 antagonist novobiocin interacts with a previously unrecognized ATP-binding domain in the carboxyl terminus of the chaperone. J Biol Chem 2000; 275: 37181-37186
  • 90 Kimura S, Ito C, Jyoko N, Segawa H, Kuroda J, Okada M, Adachi S, Nakahata T, Yuasa T, Filho VC, Furukawa H, Maekawa T. Inhibition of leukemic cell growth by a novel anticancer drug (GUT-70) from Calophyllum brasiliense that acts by induction of apoptosis. Int J Cancer 2005; 113: 158-165
  • 91 Jin L, Tabe Y, Kimura S, Zhou Y, Kuroda J, Asou H, Inaba T, Konopleva M, Andreeff M, Miida T. Antiproliferative and proapoptotic activity of GUT-70 mediated through potent inhibition of Hsp90 in mantle cell lymphoma. British J Cancer 2011; 104: 91-100
  • 92 Lu Y. Anthraquinones. In Xu R, Ye Y, Zhao W, editors. Introduction to natural products chemistry. London: CRC Press; 2012: 189-203
  • 93 Huang PH, Huang CY, Chen MC, Lee YT, Yue CH, Wang HY, Lin H. Emodin and aloe-emodin suppress breast cancer cell proliferation through ER inhibition. Evid Based Complement Alternat Med 2013; 2013: 376123
  • 94 Yan YY, Zheng LS, Zhang X, Chen LK, Singh S, Wang F, Zhang JY, Liang YJ, Dai CL, Gu LQ, Zheng MS, Talele TT, Chen ZS, Fu LW. Blockade of Her2/neu binding to Hsp90 by emodin azide methyl anthraquinone derivative induces proteasomal degradation of Her2/neu. Mol Pharmaceut 2011; 8: 1687-1697
  • 95 Fernand VE, Losso JN, Truax RE, Villar EE, Bwambok DK, Fakayode SO, Lowry M, Warner IM. Rhein inhibits angiogenesis and the viability of hormone-dependent and -independent cancer cells under normoxic or hypoxic conditions in vitro . Chem Biol Interact 2011; 192: 220-232
  • 96 Vassallo A, Vaccaro MC, De Tommasi N, Dal Piaz F, Leone A. Identification of the plant compound geraniin as a novel Hsp90 inhibitor. PLoS One 2013; 8: e74266
  • 97 Li J, Wang S, Yin J, Pan L. Geraniin induces apoptotic cell death in human lung adenocarcinoma A549 cells in vitro and in vivo . Can J Physiol Pharm 2013; 91: 1016-1024
  • 98 Zhang X-C, Chen P, He B, Wang N, Shen Z-Q. Influence of geraniin on carbonic anhydrase type II (CA II) protein in osteoclasts. Shizhen Guoyi Guoyao 2013; 24: 804-807
  • 99 Zhang X-C, Guo Y, He B, Wang N, Chen P, Shen Z-Q. Effect of geraniin on expression of carbonic anhydrase II mRNA in cultured osteoclasts. Zhongyao Yaoli Yu Linchuang 2013; 29: 32-34
  • 100 Bing SJ, Ha D, Kim MJ, Park E, Ahn G, Kim DS, Ko RK, Park JW, Lee NH, Jee Y. Geraniin down regulates gamma radiation-induced apoptosis by suppressing DNA damage. Food Chem Toxicol 2013; 57: 147-153
  • 101 Yang Y, Zhang L, Fan X, Qin C, Liu J. Antiviral effect of geraniin on human enterovirus 71 in vitro and in vivo . Bioorg Med Chem Lett 2012; 22: 2209-2211
  • 102 Serrano J, Puupponen-Pimia R, Dauer A, Aura AM, Saura-Calixto F. Tannins: current knowledge of food sources, intake, bioavailability and biological effects. Mol Nutr Food Res 2009; 53: S310-S329
  • 103 Bhattacharjee B, Vijayasarathy S, Karunakar P, Chatterjee J. Comparative reverse screening approach to identify potential anti-neoplastic targets of saffron functional components and binding mode. Asian Pac J Cancer Prev 2012; 13: 5605-5611
  • 104 Dal Piaz F, Vassallo A, Temraz A, Cotugno R, Belisario MA, Bifulco G, Chini MG, Pisano C, De Tommasi N, Braca A. A chemical-biological study reveals C9-type iridoids as novel heat shock protein 90 (Hsp90) inhibitors. J Med Chem 2013; 56: 1583-1595
  • 105 Beauchamp JK, Keast RS, Morel D, Lin J, Pika J, Han Q, Lee CH, Smith AB, Breslin PA. Phytochemistry: ibuprofen-like activity in extra-virgin olive oil. Nature 2005; 437: 45-46
  • 106 Margarucci L, Monti MC, Cassiano C, Mozzicafreddo M, Angeletti M, Riccio R, Tosco A, Casapullo A. Chemical proteomics-driven discovery of oleocanthal as an Hsp90 inhibitor. Chem Commun 2013; 49: 5844-5846
  • 107 Zhao YS, Zhu TZ, Chen YW, Yao YQ, Wu CM, Wei ZQ, Wang W, Xu YH. β-elemene inhibits Hsp90/Raf-1 molecular complex inducing apoptosis of glioblastoma cells. J Neurooncol 2012; 107: 307-314
  • 108 Ohnishi K, Ohkura S, Nakahata E, Ishisaka A, Kawai Y, Terao J, Mori T, Ishii T, Nakayama T, Kioka N, Matsumoto S, Ikeda Y, Akiyama M, Irie K, Murakami A. Non-specific protein modifications by a phytochemical induce heat shock response for self-defense. PLoS One 2013; 83: e58641
  • 109 Chao WW, Lin BF. Isolation and identification of bioactive compounds in Andrographis paniculata (Chuanxinlian). Chin Med 2010; 5: 17
  • 110 Bao Z, Guan S, Cheng C, Wu S, Wong SH, Kemeny DM, Leung BP, Wong WS. A novel antiinflammatory role for andrographolide in asthma via inhibition of the nuclear factor-κB pathway. Am J Respir Crit Care Med 2009; 179: 657-665
  • 111 Lim JC, Chan TK, Ng DS, Sagineedu SR, Stanslas J, Wong WS. Andrographolide and its analogues: versatile bioactive molecules for combating inflammation and cancer. Clin Exp Pharmacol Physiol 2012; 39: 300-310
  • 112 Abu-Ghefreh AA, Canatan H, Ezeamuzie CI. In vitro and in vivo anti-inflammatory effects of andrographolide. Int Immunopharmacol 2009; 9: 313-318
  • 113 Liang FP, Lin CH, Kuo CD, Chao HP, Fu SL. Suppression of v-Src transformation by andrographolide via degradation of the v-Src protein and attenuation of the Erk signaling pathway. J Biol Chem 2008; 283: 5023-5033
  • 114 Liu SH, Lin CH, Liang FP, Chen PF, Kuo CD, Alam MM, Maiti B, Hung SK, Chi CW, Sun CM, Fu SL. Andrographolide downregulates the v-Src and Bcr-Abl oncoproteins and induces Hsp90 cleavage in the ROS-dependent suppression of cancer malignancy. Biochem Pharmacol 2014; 87: 229-242
  • 115 Druckova A, Mernaugh RL, Ham AJ, Marnett LJ. Identification of the protein targets of the reactive metabolite of Teucrin A in vivo in the rat. Chem Res Toxicol 2007; 20: 1393-1408
  • 116 Mohebati A, Guttenplan JB, Kochhar A, Zhao ZL, Kosinska W, Subbaramaiah K, Dannenberg AJ. Carnosol, a constituent of Zyflamend, inhibits aryl hydrocarbon receptor-mediated activation of CYP1A1 and CYP1B1 transcription and mutagenesis. Cancer Prev Res 2012; 5: 593-602
  • 117 Hughes D, Guttenplan JB, Marcus CB, Subbaramaiah K, Dannenberg AJ. Heat shock protein 90 inhibitors suppress aryl hydrocarbon receptor-mediated activation of CYP1A1 and CYP1B1 transcription and DNA adduct formation. Cancer Prev Res 2008; 1: 485-493
  • 118 Zhou ZW, Xie XL, Zhou SF, Li CG. Mechanism of reversal of high glucose-induced endothelial nitric oxide synthase uncoupling by tanshinone IIA in human endothelial cell line EA.hy926. Eur J Pharmacol 2012; 697: 97-105
  • 119 Lamb J, Crawford ED, Peck D, Modell JW, Blat IC, Wrobel MJ, Lerner J, Brunet J-P, Subramanian A, Ross KN, Reich M, Hieronymus H, Wei G, Armstrong SA, Haggarty SJ, Clemons PA, Wei R, Carr SA. The Connectivity Map: using gene-expression signatures to connect small molecules, genes, and disease. Science 2006; 313: 1929-1935
  • 120 Hieronymus H, Lamb J, Ross KN, Peng XP, Clement C, Rodina A, Nieto M, Du J, Stegmaier K, Raj SM, Maloney KN, Clardy J, Hahn WC, Chiosis G, Golub TR. Gene expression signature-based chemical genomic prediction identifies a novel class of Hsp90 pathway modulators. Cancer Cell 2006; 10: 321-330
  • 121 Brandt GEL, Schmidt MD, Prisinzano TE, Blagg BSJ. Gedunin, a novel Hsp90 inhibitor: semisynthesis of derivatives and preliminary structure-activity relationships. J Med Chem 2008; 51: 6495-6502
  • 122 Dal Piaz F, Malafronte N, Romano A, Gallotta D, Belisario MA, Bifulco G, Gualtieri MJ, Sanogo R, De Tommasi N, Pisano C. Structural characterization of tetranortriterpenes from Pseudrocedrela kotschyi and Trichilia emetica and study of their activity towards the chaperone Hsp90. Phytochemistry 2012; 75: 78-89
  • 123 Gualtieri MJ, Malafronte N, Vassallo A, Braca A, Cotugno R, Vasaturo M, De Tommasi N, Dal Piaz F. Bioactive limonoids from the leaves of Azaridachta indica (Neem). J Nat Prod 2014; 77: 596-602
  • 124 Morota T, Yang CX, Sasaki H, Qin WZ, Sugama K, Miao KL, Yoshino T, Xu LH, Maruno M, Yang BH. Triterpenes from Tripterygium wilfordii . Phytochemistry 1995; 39: 1153-1157
  • 125 Salminen A, Lethonen M, Paimela T, Kaarniranta K. Celastrol: Molecular targets of Thunder God Vine. Biochem Biophys Res Commun 2010; 394: 439-442
  • 126 Davenport A, Frezza M, Shen M, Ge Y, Huo C, Chan TH, Dou QP. Celastrol and an EGCG pro-drug exhibit potent chemosensitizing activity in human leukemia cells. Int J Mol Med 2010; 25: 465-470
  • 127 Deng YN, Shi J, Liu J, Qu QM. Celastrol protects human neuroblastoma SH-SY5Y cells from rotenone-induced injury through induction of autophagy. Neurochem Int 2013; 63: 1-9
  • 128 Petronelli A, Pannitteri G, Testa U. Triterpenoids as new anticancer drugs. Anticancer Drugs 2009; 20: 880-892
  • 129 Yang H, Chen D, Cui QC, Yuan X, Dou QP. Celastrol, a triterpene extracted from the Chinese “Thunder of God Vine”, is a potent proteasome inhibitor and suppresses human prostate cancer growth in nude mice. Cancer Res 2006; 66: 4758-4765
  • 130 Cheng G, Zhang X, Zhao M, Yan W, Chen X, Wang D, Xu Y, Du Z, Yu X. Celastrol targets mitochondrial respiratory chain complex I to induce reactive oxygen species-dependent cytotoxicity in tumor cells. BMC Cancer 2011; 11: 170
  • 131 Peng B, Xu L, Cao F, Wei T, Yan C, Uzan G, Zhang D. HSP90 inhibitor, celastrol, arrests human monocytic leukemia cell U937 at G0/G1 in thiol-containing agents reversible way. Mol Cancer 2010; 9: 79
  • 132 Kim K, Lee H, Han S, Lee Y, Choe J, Kim Y, Hahn J, Ro J, Jeoung D, Kim Y. Celastrol binds to ERK and inhibits FcεRI signaling to exert an anti-allergic effect. Eur J Pharmacol 2009; 612: 131-142
  • 133 Sha M, Ye J, Zhang LX, Luan ZY, Chen YB, Huang JX. Celastrol induces apoptosis of gastric cancer cells by miR-21 inhibiting PI3K/Akt-NF-κB signaling pathway. Pharmacology 2014; 93: 39-46
  • 134 Kannaiyan R, Manu KA, Chen L, Li F, Rajendran P, Subramaniam A, Lam P, Kumar AP, Sethi G. Celastrol inhibits tumor cell proliferation and promotes apoptosis through the activation of c-Jun N-terminal kinase and suppression of PI3 K/Akt signaling pathways. Apoptosis 2011; 16: 1028-1041
  • 135 Fan XX, Li N, Wu JL, Zhou YL, He JX, Liu L, Leung ELH. Celastrol induces apoptosis in gefitinib-resistant non-small cell lung cancer cells via caspases-dependent pathways and Hsp90 client protein degradation. Molecules 2014; 19: 3508-3522
  • 136 Feng L, Zhang D, Fan C, Ma C, Yang W, Meng Y, Wu W, Guan S, Jiang B, Yang M. ER stress-mediated apoptosis induced by celastrol in cancer cells and important role of glycogen synthase kinase-3β in the signal network. Cell Death Dis 2013; 4: e715
  • 137 Lu Z, Jin Y, Qiu L, Lai Y, Pan J. Celastrol, a novel HSP90 inhibitor, depletes Bcr-Abl and induces apoptosis in imatinib-resistant chronic myelogenous leukemia cells harboring T315I mutation. Cancer Lett 2010; 290: 182-191
  • 138 Zhang T, Hamza A, Cao X, Wang B, Yu S, Zhan CG, Sun D. A novel Hsp90 inhibitor to disrupt Hsp90/Cdc37 complex against pancreatic cancer cells. Mol Cancer Ther 2008; 7: 162-170
  • 139 Sreeramulu S, Gande SL, Göbel M, Schwalbe H. Molecular mechanism of inhibition of the human protein complex Hsp90-Cdc37, a kinone chaperone-cochaperone, by triterpene celastrol. Angew Chem Int Ed 2009; 48: 5853-5855
  • 140 Zhang T, Li Y, Yu Y, Zou P, Jiang Y, Sun D. Characterization of celastrol to inhibit Hsp90 and Cdc37 interaction. J Biol Chem 2009; 284: 35381-35389
  • 141 Chadli A, Felts SJ, Wang Q, Sullivan WP, Botuyan MV, Fauq A, Ramirez-Alvarado M, Mer G. Celastrol inhibits Hsp90 chaperoning of steroid receptors by inducing fibrillization of the co-chaperone p 23. J Biol Chem 2010; 285: 4224-4231
  • 142 Zhang D, Xu L, Cao F, Wei T, Yang C, Uzan G, Peng B. Celastrol regulates multiple nuclear transcription factors belonging to Hsp90′s clients in a dose- and cell type-dependent way. Cell Stress Chaperon 2010; 15: 939-946
  • 143 Zanphorlin LM, Alves FR, Ramos CH. The effect of celastrol, a triterpene with antitumorigenic activity, on conformational and functional aspects of the human 90 KDa heat shock protein Hsp90α, a chaperone implicated in the stabilization of the tumor phenotype. Biochim Biophys Acta 2014; 1840: 3145-3152
  • 144 Pyo JS, Roh SH, Kim DK, Lee JG, Lee YY, Hong SS, Kwon SW, Park JH. Anticancer effect of betulin on a human lung cancer cell line: a pharmacoproteomic approach using 2D SDS PAGE coupled with nano-HPLC tandem mass spectrometry. Planta Med 2009; 75: 127-131
  • 145 Ding L, Xu FC, Wang H, Ou QM. Studies on chemical constituents from Patrinia heterophylla Bunge and their cytotoxicity in vitro . J Northwest Normal University (Natural Science) 2007; 43: 62-65
  • 146 Wei DF, Wei YX, Cheng WD, Yan MF, Su G, Hu Y, Ma YQ, Han C, Lu Y, Cao HM, Bao YC. Proteomic analysis of the effect of triterpenes from Patrinia heterophylla on leukemia K562 cells. J Ethnopharmacol 2012; 144: 576-583
  • 147 Haginaka J, Kitabatake T, Hirose I, Matsunaga H, Moaddel R. Interaction of cepharanthine with immobilized heat shock protein 90α (Hsp90α) and screening of Hsp90α inhibitors. Anal Biochem 2013; 434: 202-206
  • 148 Rogosnitzky M, Danks R. Therapeutic potential of the biscoclaurine alkaloid, cepharanthine, for a range of clinical conditions. Pharmacol Rep 2011; 63: 337-347
  • 149 Tang J, Feng Y, Tsao S, Wang N, Curtain R, Wang Y. Berberine and Coptidis rhizome as novel antineoplastic agents: a review of traditional use and biomedical investigations. J Ethnopharmacol 2009; 126: 5-17
  • 150 Rahmatullah M, Jahan R, Bashar ABMA, Al-Nahain A, Majumder S, Islam T, Das PR. A review on berbamine – a potential anticancer drug. J Pharm Pharm Sci 2014; 3: 95-110
  • 151 Diogo CV, Machado NG, Barbosa IA, Serafim TL, Burgeiro A, Oliveira PJ. Berberine as a promising safe anticancer agent – is there a role for mitochondria?. Curr Drug Targets 2011; 12: 850-859
  • 152 Jabbarzadeh KP, Rahmat A, Ismail P, Ling KH. Targets and mechanisms of berberine, a natural drug with potential to treat cancer with special focus on breast cancer. Eur J Pharmacol 2014; 740: 584-595
  • 153 Sun JR, Zhang XH, He ZW, Gu Y, Yu YZ, Fang YM, Lu QH, Dong QH, Xu RZ. The mechanism of apoptosis of chronic myeloid leukemia cells induced by the novel p 210 bcr/abl inhibitor berbamine. Zhonghua Yi Xue Za Zhi 2006; 86: 2246-2251
  • 154 Dal Piaz F, Vassallo A, Chini MG, Cordero FM, Cardona F, Pisano C, Bifulco G, De Tommasi N, Brandi A. Natural iminosugar (+)-lentiginosine inhibits ATPase and chaperone activity of hsp90. PloS One 2012; 7: e43316
  • 155 Pastuszak I, Molyneux RJ, James LF, Elbein AD. Lentiginosine, a dihydroxyindolizidine alkaloid that inhibits amyloglucosidase. Biochemistry 1990; 29: 1886-1891
  • 156 Ren Y, Yuan C, Chai HB, Ding Y, Li XC, Ferreira D, Kinghorn AD. Absolute configuration of (−)-gambogic acid, an antitumor agent. J Nat Prod 2011; 74: 460-463
  • 157 Zhang L, Yi Y, Chen J, Sun Y, Guo Q, Zheng Z, Song S. Gambogic acid inhibits Hsp90 and deregulates TNF-α/NF-κB in HeLa cells. Biochem Biophys Res Commun 2010; 403: 282-287
  • 158 Davenport J, Manjarrez JR, Peterson L, Krumm B, Blagg BS, Matts RL. Gambogic acid, a natural product inhibitor of Hsp90. J Nat Prod 2011; 74: 1085-1092