Dual PI3K/mTOR inhibitor NVP-BEZ235-induced apoptosis of hepatocellular carcinoma cell lines is enhanced by inhibitors of autophagy

Chang,Zhexing; Shi,Guang; Jin,Jiqiang; Guo,Huatao; Guo,Xuefeng; Luo,Fangyue; Song,Yuguo; Jia,Xiaojing

doi:10.3892/ijmm.2013.1351

Dual PI3K/mTOR inhibitor NVP-BEZ235-induced apoptosis of hepatocellular carcinoma cell lines is enhanced by inhibitors of autophagy

Authors:
- Zhexing Chang
- Guang Shi
- Jiqiang Jin
- Huatao Guo
- Xuefeng Guo
- Fangyue Luo
- Yuguo Song
- Xiaojing Jia
View Affiliations

Affiliations: Department of Oncology, Beihua Affiliated Hospital, Jilin 132000, P.R. China, Department of Oncology, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China, The Second Group of Oncology, Jilin Central Hospital, Jilin 132000, P.R. China, Department of Cardiology, Beihua Affiliated Hospital, Jilin 132000, P.R. China, Department of Emergency, Beihua Affiliated Hospital, Jilin 132000, P.R. China, Department of Pediatrics, Beihua Affiliated Hospital, Jilin 132000, P.R. China, Department of Immunity, Beihua Affiliated Hospital, Jilin 132000, P.R. China, Department of Tumor Radiotherapy, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China
Published online on: April 16, 2013 https://doi.org/10.3892/ijmm.2013.1351
Pages: 1449-1456

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

Dysregulation of the phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling has been found in several types of human cancer, including hepatocellular carcinoma (HCC). NVP-BEZ235 is a novel, orally bioavailable dual PI3K/mTOR inhibitor that has exhibited promising activity against HCC in preclinical models. Autophagy is a cellular lysosomal degradation pathway essential for the regulation of cell survival and death to maintain homeostasis. This process is negatively regulated by mTOR signaling and often counteracts the efficacy of certain cancer therapeutic agents. In this study, we explored the role of autophagy in apoptosis induced by NVP-BEZ235 in two HCC cell lines, Hep3B and PLC/PRF/5, and identified the mechanism of combinatorial treatment. NVP-BEZ235 was effective in inhibiting the growth of the two HCC cell lines possibly though induction of apoptosis. NVP-BEZ235 also potently increased the expression of LC3-II and decreased the expression of p62, indicating induction of autophagy. When NVP-BEZ235 was used in combination with Atg5 siRNA or the autophagy inhibitor 3-methyladenine (3-MA), enhancement of the inhibitory effects on the growth of HCC cells was detected. In addition, enhanced induction of apoptosis was observed in cells exposed to the combination of NVP-BEZ235 and Atg5 siRNA or 3-MA. Thus, induction of autophagy by NVP-BEZ235 may be a survival mechanism that counteracts its anticancer effects. Based on these data, we suggest a strategy to enhance the anticancer efficacy of BEZ235 by blockade of autophagy. Thus, our study provides a rationale for the clinical development of combinations of NVP-BEZ235 and autophagy inhibitors for the treatment of HCC and other malignancies.

View Figures

View References

1	El-Serag HB and Rudolph KL: Hepatocellular carcinoma: epidemiology and molecular carcinogenesis. Gastroenterology. 132:2557–2576. 2007. View Article : Google Scholar : PubMed/NCBI
2	Siegel R, Naishadham D and Jemal A: Cancer statistics, 2012. CA Cancer J Clin. 62:10–29. 2012. View Article : Google Scholar
3	Verslype C, Van Cutsem E, Dicato M, et al: The management of hepatocellular carcinoma. Current expert opinion and recommendations derived from the 10th World Congress on Gastrointestinal Cancer, Barcelona, 2008. Ann Oncol. 20(Suppl 7): vii1–vii6. 2009. View Article : Google Scholar
4	Sia D and Villanueva A: Signaling pathways in hepatocellular carcinoma. Oncology. 81(Suppl 1): S18–S23. 2011. View Article : Google Scholar
5	Vivanco I and Sawyers CL: The phosphatidylinositol 3-Kinase AKT pathway in human cancer. Nat Rev Cancer. 2:489–501. 2002. View Article : Google Scholar : PubMed/NCBI
6	Luo J, Manning BD and Cantley LC: Targeting the PI3K-Akt pathway in human cancer: rationale and promise. Cancer Cell. 4:257–262. 2003. View Article : Google Scholar : PubMed/NCBI
7	Sabatini DM: mTOR and cancer: insights into a complex relationship. Nat Rev Cancer. 6:729–734. 2006. View Article : Google Scholar : PubMed/NCBI
8	Kong D and Yamori T: Advances in development of phosphatidylinositol 3-kinase inhibitors. Curr Med Chem. 16:2839–2854. 2009. View Article : Google Scholar : PubMed/NCBI
9	Pang RW and Poon RT: From molecular biology to targeted therapies for hepatocellular carcinoma: the future is now. Oncology. 72(Suppl 1): S30–S44. 2007. View Article : Google Scholar : PubMed/NCBI
10	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
11	Levine B and Kroemer G: Autophagy in the pathogenesis of disease. Cell. 132:27–42. 2008. View Article : Google Scholar : PubMed/NCBI
12	Rubinsztein DC, Gestwicki JE, Murphy LO and Klionsky DJ: Potential therapeutic applications of autophagy. Nat Rev Drug Discov. 6:304–312. 2007. View Article : Google Scholar : PubMed/NCBI
13	Masuda M, Shimomura M, Kobayashi K, et al: Growth inhibition by NVP-BEZ235, a dual PI3K/mTOR inhibitor, in hepatocellular carcinoma cell lines. Oncol Rep. 26:1273–1279. 2011.PubMed/NCBI
14	Thomas HE, Mercer CA, Carnevalli LS, et al: mTOR inhibitors synergize on regression, reversal of gene expression, and autophagy in hepatocellular carcinoma. Sci Transl Med. 4:139–184. 2012. View Article : Google Scholar : PubMed/NCBI
15	Herrera VA, Zeindl-Eberhart E, Jung A, et al: The dual PI3K/mTOR inhibitor BEZ235 is effective in lung cancer cell lines. Anticancer Res. 31:849–854. 2011.PubMed/NCBI
16	Shire AM and Roberts LR: Prevention of hepatocellular carcinoma: progress and challenges. Minerva Gastroenterol Dietol. 58:49–64. 2012.PubMed/NCBI
17	Sandhu DS, Tharayil VS, Lai JP and Roberts LR: Treatment options for hepatocellular carcinoma. Expert Rev Gastroenterol Hepatol. 2:81–92. 2008. View Article : Google Scholar
18	Roberts LR and Gores GJ: Emerging drugs for hepatocellular carcinoma. Expert Opin Emerg Drugs. 11:469–487. 2006. View Article : Google Scholar : PubMed/NCBI
19	Tokunaga E, Oki E, Egashira A, et al: Deregulation of the Akt pathway in human cancer. Curr Cancer Drug Targets. 8:27–36. 2008. View Article : Google Scholar : PubMed/NCBI
20	Zou CY, Smith KD, Zhu QS, et al: Dual targeting of AKT and mammalian target of rapamycin: a potential therapeutic approach for malignant peripheral nerve sheath tumor. Mol Cancer Ther. 8:1157–1168. 2009. View Article : Google Scholar : PubMed/NCBI
21	Xu CX, Zhao L, Yue P, et al: Augmentation of NVP-BEZ235’s anticancer activity against human lung cancer cells by blockage of autophagy. Cancer Biol Ther. 12:549–555. 2011.
22	Mirzoeva OK, Hann B, Hom YK, et al: Autophagy suppression promotes apoptotic cell death in response to inhibition of the PI3K-mTOR pathway in pancreatic adenocarcinoma. J Mol Med. 89:877–889. 2011. View Article : Google Scholar : PubMed/NCBI
23	Jung CH, Jun CB, Ro SH, et al: ULK-Atg13-FIP200 complexes mediate mTOR signaling to the autophagy machinery. Mol Biol Cell. 20:1992–2003. 2009. View Article : Google Scholar : PubMed/NCBI
24	Fujiwara K, Iwado E, Mills GB, et al: Akt inhibitor shows anticancer and radiosensitizing effects in malignant glioma cells by inducing autophagy. Int J Oncol. 31:753–760. 2007.PubMed/NCBI
25	Yang S, Xiao X, Meng X and Leslie KK: A mechanism for synergy with combined mTOR and PI3 kinase inhibitors. PLoS One. 6:e263432011. View Article : Google Scholar : PubMed/NCBI
26	Danial NN and Korsmeyer SJ: Cell death: critical control points. Cell. 116:205–219. 2004. View Article : Google Scholar : PubMed/NCBI
27	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
28	Mizushima N and Klionsky DJ: Protein turnover via autophagy: implications for metabolism. Annu Rev Nutr. 27:19–40. 2007. View Article : Google Scholar : PubMed/NCBI
29	Eisenberg-Lerner A, Bialik S, Simon HU and Kimchi A: Life and death partners: apoptosis, autophagy and the cross-talk between them. Cell Death Differ. 16:966–975. 2009. View Article : Google Scholar : PubMed/NCBI
30	Yang Y, Xing D, Zhou F and Chen Q: Mitochondrial autophagy protects against heat shock-induced apoptosis through reducing cytosolic cytochrome c release and downstream caspase-3 activation. Biochem Biophys Res Commun. 395:190–195. 2010. View Article : Google Scholar
31	Zhuang W, Qin Z and Liang Z: The role of autophagy in sensitizing malignant glioma cells to radiation therapy. Acta Biochim Biophys Sin. 41:341–351. 2009. View Article : Google Scholar : PubMed/NCBI
32	White E and DiPaola RS: The double-edged sword of autophagy modulation in cancer. Clin Cancer Res. 15:5308–5316. 2009. View Article : Google Scholar : PubMed/NCBI
33	Dikic I, Johansen T and Kirkin V: Selective autophagy in cancer development and therapy. Cancer Res. 70:3431–3434. 2010. View Article : Google Scholar : PubMed/NCBI
34	Nguyen TM, Subramanian IV, Xiao X, et al: Endostatin induces autophagy in endothelial cells by modulating Beclin 1 and beta-catenin levels. J Cell Mol Med. 13:3687–3698. 2009. View Article : Google Scholar : PubMed/NCBI
35	Nguyen TM, Subramanian IV, Kelekar A and Ramakrishnan S: Kringle 5 of human plasminogen, an angiogenesis inhibitor, induces both autophagy and apoptotic death in endothelial cells. Blood. 109:4793–4802. 2007. View Article : Google Scholar : PubMed/NCBI