Celastrus orbiculatus extract triggers apoptosis and autophagy via PI3K/Akt/mTOR inhibition in human colorectal cancer cells

Yang,Lin; Liu,Yanqing; Wang,Mei; Qian,Yayun; Dai,Xiaojun; Zhu,Yaodong; Chen,Jue; Guo,Shiyu; Hisamitsu,Tadashi

doi:10.3892/ol.2016.5213

Celastrus orbiculatus extract triggers apoptosis and autophagy via PI3K/Akt/mTOR inhibition in human colorectal cancer cells

Authors:
- Lin Yang
- Yanqing Liu
- Mei Wang
- Yayun Qian
- Xiaojun Dai
- Yaodong Zhu
- Jue Chen
- Shiyu Guo
- Tadashi Hisamitsu
View Affiliations

Affiliations: Institute of Traditional Chinese Medicine and Western Medicine, School of Medicine, Yangzhou University, Yangzhou, Jiangsu 225009, P.R. China, Department of Physiology, School of Medicine, Showa University, Tokyo 142‑8555, Japan
Published online on: September 29, 2016 https://doi.org/10.3892/ol.2016.5213
Pages: 3771-3778
Copyright: © Yang et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

Metrics: Total Views: 0 (Spandidos Publications: | PMC Statistics: )

Metrics: Total PDF Downloads: 0 (Spandidos Publications: | PMC Statistics: )

Cited By (CrossRef): 0 citations Loading Articles...

Abstract

Celastrus orbiculatus is used as a folk medicine in China for the treatment of numerous diseases. The ethyl acetate extract of Celastrus orbiculatus (COE) also displays a wide range of anti‑cancer activities in the laboratory. However, the effectiveness of COE‑induced autophagy and its mechanism of action in colorectal cancer cells have not been investigated thus far. The present study analyzed the effect of COE on HT‑29 cell viability, apoptosis and autophagy using MTT assay, flow cytometry, transmission electron microscopy and western blotting. Additionally, the autophagy inhibitor 3‑methyladenine and the autophagy inducer rapamycin were used to further explore the effects of COE‑induced autophagy in HT‑29 cells. The present study also examined whether the phosphatidylinositol‑4,5‑bisphosphate 3‑kinase (PI3K)/Akt/mechanistic target of rapamycin (mTOR)/p70 ribosomal protein S6 kinase (p70S6K) signaling pathway was involved in the regulation of COE‑induced autophagy. The results revealed that COE inhibited HT‑29 cell proliferation and decreased cell survival in a time‑ and dose‑dependent manner, and that COE possessed the ability to induce both apoptosis and autophagy in HT‑29 cells. Furthermore, autophagy and apoptosis induced by COE synergized to inhibit colorectal cancer growth. In addition, COE treatment decreased the phosphorylation of Akt and its downstream effectors mTOR and p70S6K. Taken together, these results demonstrate that both autophagy and apoptosis were activated during COE treatment of HT‑29 cells, and that COE‑induced autophagy decreases the viability of HT‑29 cells via a mechanism that may depend on the PI3K/Akt/mTOR/p70S6K signaling pathway. Furthermore, compounds that induce autophagy administered in combination with COE may be an attractive strategy for enhancing the anti‑tumor potency of COE in colorectal cancer.

View Figures

View References

1	Guo YQ, Li X, Xu J, Li N, Meng DL and Wang JH: Sesquiterpene esters from the fruits of Celastrus orbiculatus. Chem Pharm Bull (Tokyo). 52:1134–1136. 2004. View Article : Google Scholar : PubMed/NCBI
2	Jin HZ, Hwang BY, Kim HS, Lee JH, Kim YH and Lee JJ: Antiinflammatory constituents of Celastrus orbiculatus inhibit the NF-kappa B activation and NO production. J Nat Prod. 65:89–91. 2002. View Article : Google Scholar : PubMed/NCBI
3	Li GQ, Liu D, Zhang Y, Qian Y, Zhang H, Guo S, Sunagawa M, Hisamitsu T and Liu Y: Celastrol inhibits lipopolysaccharide-stimulated rheumatoid fibroblast-like synoviocyte invasion through suppression of TLR4/NF-κB-mediated matrix metalloproteinase-9 expression. PloS One. 8:e689052013. View Article : Google Scholar : PubMed/NCBI
4	Li GQ, Liu D, Zhang Y, Qian YY, Zhu YD, Guo SY, Sunagawa M, Hisamitsu T and Liu YQ: Anti-invasive effects of celastrol in hypoxia-induced fibroblast-like synoviocyte through suppressing of HIF-1α/CXCR4 signaling pathway. Int Immunopharmacol. 17:1028–1036. 2013. View Article : Google Scholar : PubMed/NCBI
5	Spivey AC, Weston M and Woodhead S: Celastraceae sesquiterpenoids: Biological activity and synthesis. Chem Soc Rev. 31:43–59. 2002. View Article : Google Scholar : PubMed/NCBI
6	Kim SE, Kim YH, Lee JJ and Kim YC: A new sesquiterpene ester from Celastrus orbiculatus reversing multidrug resistance in cancer cells. J Nat Prod. 61:108–111. 1998. View Article : Google Scholar : PubMed/NCBI
7	Westerheide SD, Bosman JD, Mbadugha BN, Kawahara TL, Matsumoto G, Kim S, Gu W, Devlin JP, Silverman RB and Morimoto RI: Celastrols as inducers of the heat shock response and cytoprotection. J Biol Chem. 279:56053–56060. 2004. View Article : Google Scholar : PubMed/NCBI
8	Nam NH: Naturally occurring NF-kappaB inhibitors. Mini Rev Med Chem. 6:945–951. 2006. View Article : Google Scholar : PubMed/NCBI
9	Zhang H, Qian Y, Liu Y, Li G, Cui P, Zhu Y, Ma H, Ji X, Guo S and Tadashi H: Celastrus orbiculatus extract induces mitochondrial-mediated apoptosis in human hepatocellular carcinoma cells. J Tradit Chin Med. 32:621–626. 2012. View Article : Google Scholar : PubMed/NCBI
10	Qian YY, Zhang H, Hou Y, Yuan L, Li GQ, Guo SY, Hisamits T and Liu YQ: Celastrus orbiculatus extract inhibits tumor angiogenesis by targeting vascular endothelial growth factor signaling pathway and shows potent antitumor activity in hepatocarcinomas in vitro and in vivo. Chin J Integr Med. 18:752–760. 2012. View Article : Google Scholar : PubMed/NCBI
11	Zhu YD, Liu YQ, Qian YY, Zhang H, Li GQ and Yang L: Extracts of Celastrus orbiculatus exhibit anti-proliferative and anti-invasive effects on human gastric adenocarcinoma cells. Chin J Integr Med. 2014.(Epub ahead of print). View Article : Google Scholar
12	Zhu Y, Liu Y, Qian Y, Dai X, Yang L, Chen J, Guo S and Hisamitsu T: Antimetastatic effects of Celastrus orbiculatus on human gastric adenocarcinoma by inhibiting epithelial-mesenchymal transition and NF-κB/snail signaling pathway. Integr Cancer Ther. 14:271–281. 2015. View Article : Google Scholar : PubMed/NCBI
13	Lefranc F, Facchini V and Kiss R: Proautophagic drugs: A novel means to combat apoptosis-resistant cancers, with a special emphasis on glioblastomas. Oncologist. 12:1395–1403. 2007. View Article : Google Scholar : PubMed/NCBI
14	Levine B and Klionsky DJ: Development by self-digestion: Molecular mechanisms and biological functions of autophagy. Dev Cell. 6:463–477. 2004. View Article : Google Scholar : PubMed/NCBI
15	Levine B and Kroemer G: Autophagy in the pathogenesis of disease. Cell. 132:27–42. 2008. View Article : Google Scholar : PubMed/NCBI
16	Mizushima N, Levine B, Cuervo AM and Klionsky DJ: Autophagy fights disease through cellular self-digestion. Nature. 451:1069–1075. 2008. View Article : Google Scholar : PubMed/NCBI
17	Li J, Hou N, Faried A, Tsutsumi S and Kuwano H: Inhibition of autophagy augments 5-fluorouracil chemotherapy in human colon cancer in vitro and in vivo model. Eur J Cancer. 46:1900–1909. 2010. View Article : Google Scholar : PubMed/NCBI
18	Sharma N, Thomas S, Golden EB, Hofman FM, Chen TC, Petasis NA, Schönthal AH and Louie SG: Inhibition of autophagy and induction of breast cancer cell death by mefloquine, an antimalarial agent. Cancer Lett. 326:143–154. 2012. View Article : Google Scholar : PubMed/NCBI
19	Xi G, Hu X, Wu B, Jiang H, Young CY, Pang Y and Yuan H: Autophagy inhibition promotes paclitaxel-induced apoptosis in cancer cells. Cancer Lett. 307:141–148. 2011. View Article : Google Scholar : PubMed/NCBI
20	Pan X, Zhang X, Sun H, Zhang J, Yan M and Zhang H: Autophagy inhibition promotes 5-fluorouraci-induced apoptosis by stimulating ROS formation in human non-small cell lung cancer A549 cells. PloS One. 8:e566792013. View Article : Google Scholar : PubMed/NCBI
21	Ravikumar B, Vacher C, Berger Z, Davies JE, Luo S, Oroz LG, Scaravilli F, Easton DF, Duden R, O'Kane CJ and Rubinsztein DC: Inhibition of mTOR induces autophagy and reduces toxicity of polyglutamine expansions in fly and mouse models of Huntington disease. Nat Genet. 36:585–595. 2004. View Article : Google Scholar : PubMed/NCBI
22	Cui Q, Tashiro S, Onodera S, Minami M and Ikejima T: Autophagy preceded apoptosis in oridonin-treated human breast cancer MCF-7 cells. Biol Pharm Bull. 30:859–864. 2007. View Article : Google Scholar : PubMed/NCBI
23	Iwamaru A, Kondo Y, Iwado E, Aoki H, Fujiwara K, Yokoyama T, Mills GB and Kondo S: Silencing mammalian target of rapamycin signaling by small interfering RNA enhances rapamycin-induced autophagy in malignant glioma cells. Oncogene. 26:1840–1851. 2007. View Article : Google Scholar : PubMed/NCBI
24	Maiuri MC, Le Toumelin G, Criollo A, Rain JC, Gautier F, Juin P, Tasdemir E, Pierron G, Troulinaki K, Tavernarakis N, et al: Functional and physical interaction between Bcl-X(L) and a BH3-like domain in Beclin-1. EMBO J. 26:2527–2539. 2007. View Article : Google Scholar : PubMed/NCBI
25	Shintani T and Klionsky DJ: Autophagy in health and disease: A double-edged sword. Science. 306:990–995. 2004. View Article : Google Scholar : PubMed/NCBI
26	Levine B and Yuan J: Autophagy in cell death: An innocent convict? J Clin Invest. 115:2679–2688. 2005. View Article : Google Scholar : PubMed/NCBI
27	Kenific CM, Thorburn A and Debnath J: Autophagy and metastasis: Another double-edged sword. Curr Opin Cell Biol. 22:241–245. 2010. View Article : Google Scholar : PubMed/NCBI
28	Lock R and Debnath J: Extracellular matrix regulation of autophagy. Curr Opin Cell Biol. 20:583–588. 2008. View Article : Google Scholar : PubMed/NCBI
29	Li JJ, Yang J, Lu F, et al: Chemical constituents from the stems of Celastrus Orbiculatus. Chin J Nat Med. 10:279–283. 2012. View Article : Google Scholar
30	Zan K, Chen X-Q, Wang Q, et al: Chemical constituents in stem of Celastrus orbiculatus. Chin Trad Herbal Drugs. 38:14552007.
31	Livak KJ and Schmittgen TD: Analysis of relative gene expression data using real-time quantitative PCR and the 2(−Delta Delta C(T)) method. Methods. 25:402–408. 2001. View Article : Google Scholar : PubMed/NCBI
32	Tait SW, Ichim G and Green DR: Die another way-non-apoptotic mechanisms of cell death. J Cell Sci. 127:2135–2144. 2014. View Article : Google Scholar : PubMed/NCBI
33	Levine B, Sinha S and Kroemer G: Bcl-2 family members: Dual regulators of apoptosis and autophagy. Autophagy. 4:600–606. 2008. View Article : Google Scholar : PubMed/NCBI
34	Ferlay J, Autier P, Boniol M, Heanue M, Colombet M and Boyle P: Estimates of the cancer incidence and mortality in Europe in 2006. Ann Oncol. 18:581–592. 2007. View Article : Google Scholar : PubMed/NCBI
35	Ramakrishnan S, Nguyen TM, Subramanian IV and Kelekar A: Autophagy and angiogenesis inhibition. Autophagy. 3:512–515. 2007. View Article : Google Scholar : PubMed/NCBI
36	Thomas S, Quinn BA, Das SK, Dash R, Emdad L, Dasgupta S, Wang XY, Dent P, Reed JC, Pellecchia M, et al: Targeting the Bcl-2 family for cancer therapy. Expert Opin Ther Targets. 17:61–75. 2013. View Article : Google Scholar : PubMed/NCBI
37	Jung CH, Ro SH, Cao J, Otto NM and Kim DH: mTOR regulation of autophagy. FEBS Lett. 584:1287–1295. 2010. View Article : Google Scholar : PubMed/NCBI
38	Maiso P, Liu Y, Morgan B, Azab AK, Ren P, Martin MB, Zhang Y, Liu Y, Sacco A, Ngo H, et al: Defining the role of TORC1/2 in multiple myeloma. Blood. 118:6860–6870. 2011. View Article : Google Scholar : PubMed/NCBI
39	Corradetti MN and Guan KL: Upstream of the mammalian target of rapamycin: Do all roads pass through mTOR? Oncogene. 25:6347–6360. 2006. View Article : Google Scholar : PubMed/NCBI