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Wu T, Yao Y, Sun R, Wang H, Zhang J, Yin X, Zhou Q, Huangfu C. Arterial instillation of rapamycin in treatment of rabbit hepatic xenograft tumors and its effects on VEGF, iNOS, HIF-1α, Bcl-2, Bax expression and microvessel density. Sci Prog 2021; 104:368504211026417. [PMID: 34392719 PMCID: PMC10364938 DOI: 10.1177/00368504211026417] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hepatocellular carcinoma is one of the leading causes of malignant tumor related death word wide with poor prognosis. Chemotherapy and TACE are main treatment methods for advanced stage cases. Rapamycin, a macrolide compound that initially used to coat coronary stents, can inhibit the growth of a variety of cancer cells especially hepatocellular carcinoma. Twenty-four healthy adult New Zealand white rabbits underwent CT-guided puncture to prepare a model of VX2 liver xenograft tumor. The rabbits were randomly divided into four groups with six in each group and received the following treatments: APR-TACE1: arterial perfusion of high-dose rapamycin combined with TACE; APR-TACE2: arterial perfusion of low-dose rapamycin combined with TACE; TACE: TACE alone; and IVR-TACE: intravenous injection of rapamycin combined with TACE. Two weeks after TACE treatment, the rabbits received CT scan and DSA angiography examination, and then killed by air embolism. The non-necrotic region and surrounding tissues were obtained from the peripheral tumor for iNOS, HIF-1α, VEGF, Bcl-2, and Bax protein expression analysis. Protein expression of iNOS, HIF-1α, VEGF, and Bcl-2 in APR-TACE1 were significantly lower than those in groups APR-TACE2, TACE, and IVR-TACE (p < 0.05). iNOS, HIF-1α, and VEGF in APR-TACE2 were lower than those in TACE (p < 0.05). iNOS and VEGF in APR-TACE2 were significantly lower than those in IVR-TACE (p < 0.05). iNOS in IVR-TACE was significantly lower than that in TACE (p < 0.05). The expression levels of Bcl-2 and Bax were statistically significant between APR-TACE2 and TACE (p < 0.05). The MVD of the tumor tissue in APR-TACE1 was lower than that of groups APR-TACE2, TACE, IVR-TACE with statistical difference (p < 0.05). However, MVD of APR-TACE2 was lower than that of groups TACE, IVR-TACE with significant statistical difference (p < 0.05). Arterial instillation of rapamycin+TACE in treatment of rabbit hepatic xenograft tumors can reduce tumor neovascularization and inhibit iNOS, HIF-1α, VEGF, Bcl-2, and Bax protein expression.
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Affiliation(s)
- Tao Wu
- Department of Radiology Intervention, The First affiliated Hospital of Henan University of Traditional Chinese Medicine (TMC), Zhengzhou, Henan, P.R. China
- Department of Radiology Intervention, The First Affiliated Hospital of Henan University, Kaifeng, Henan, P.R. China
| | - Yihui Yao
- Department of Radiology Intervention, The First Affiliated Hospital of Henan University, Kaifeng, Henan, P.R. China
| | - Ruimin Sun
- Department of Radiology Intervention, The First affiliated Hospital of Henan University of Traditional Chinese Medicine (TMC), Zhengzhou, Henan, P.R. China
| | - Huili Wang
- Department of Radiology Intervention, The First affiliated Hospital of Henan University of Traditional Chinese Medicine (TMC), Zhengzhou, Henan, P.R. China
| | - Junna Zhang
- Department of Pathology, The First Affiliated Hospital of Henan University, Kaifeng, Henan, P.R. China
| | - Xiaoxiang Yin
- Department of Radiology Intervention, The First Affiliated Hospital of Henan University, Kaifeng, Henan, P.R. China
| | - Qing Zhou
- Department of Radiology Intervention, The First Affiliated Hospital of Henan University, Kaifeng, Henan, P.R. China
| | - Chaoshen Huangfu
- College of Basic Medicine, Henan University, Kaifeng, Henan, P.R. China
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Feng H, Yang Z, Bai X, Yang M, Fang Y, Zhang X, Guo Q, Ning H. Therapeutic potential of a dual mTORC1/2 inhibitor for the prevention of posterior capsule opacification: An in vitro study. Int J Mol Med 2018; 41:2099-2107. [PMID: 29344639 PMCID: PMC5810205 DOI: 10.3892/ijmm.2018.3398] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 01/10/2018] [Indexed: 12/14/2022] Open
Abstract
Mammalian target of rapamycin (mTOR) serves a central role in regulating cell growth and survival, and has been demonstrated to be involved in the pathological progression of posterior capsule opacification (PCO). In the present study, the potency of PP242, a novel dual inhibitor of mTOR complex 1/2 (mTORC1/2), in the suppression of the growth of human lens epithelial cells (HLECs) was investigated. Using a Cell Counting Kit‑8 and a wound healing assay, it was demonstrated that PP242 inhibited the proliferation and migration of HLECs. In addition, western blot analysis indicated that PP242 completely inhibited mTORC1 and mTORC2 downstream signaling activities, whereas rapamycin only partially inhibited mTORC1 activity within LECs. Furthermore, PP242 treatment led to an upregulation of the expression levels of p53 and B cell lymphoma‑2 (Bcl‑2)‑associated X and downregulation of Bcl‑2. In addition, flow cytometric analysis demonstrated that PP242 induced the cell cycle arrest at the G0/G1 phase, which may have caused apoptosis and induced autophagy within the LECs. The results of the present study suggested that administration of PP242 may potentially offer a novel therapeutic approach for the prevention of PCO.
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Affiliation(s)
- Hao Feng
- Department of Ophthalmology, The First Hospital of China Medical University
| | - Zhibo Yang
- Department of Ophthalmology, The Fourth People’s Hospital of Shenyang
| | - Xue Bai
- Department of Ophthalmology, The First Hospital of China Medical University
| | - Meirong Yang
- Department of Ophthalmology, The First Hospital of China Medical University
| | - Yuan Fang
- Department of Ophthalmology, The First Hospital of China Medical University
| | - Xiaonan Zhang
- Department of Ophthalmology, The First Hospital of China Medical University
| | - Qiqiang Guo
- Key Laboratory of Medical Cell Biology, College of Translational Medicine, China Medical University, Shenyang, Liaoning 110001, P.R. China
| | - Hong Ning
- Department of Ophthalmology, The First Hospital of China Medical University
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Reed DE, Shokat KM. INPP4B and PTEN Loss Leads to PI-3,4-P2 Accumulation and Inhibition of PI3K in TNBC. Mol Cancer Res 2017; 15:765-775. [PMID: 28196852 DOI: 10.1158/1541-7786.mcr-16-0183] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 07/07/2016] [Accepted: 01/17/2017] [Indexed: 01/06/2023]
Abstract
Triple-negative breast cancer [TNBC, lacks expression of estrogen receptor (ER), progesterone receptor (PR), and amplification of HER2/Neu] remains one of the most aggressive subtypes, affects the youngest patients, and still lacks an effective targeted therapy. Both phosphatidylinositol-3-kinase (PI3K)-α and -β contribute to oncogenesis of solid tumors, including the development of breast cancer. Inositol polyphosphate-4-phosphatase type II (INPP4B) catalyzes the removal of the 4'-phosphate of phosphatidylinositol-(3, 4)-bisphosphate (PI-3,4-P2), creating phosphatidylinositol-3-phosphate. There is debate concerning whether PI-3,4-P2 contributes to Akt and downstream effector activation with the known canonical signaling second messenger, phosphatidylinositol-(3, 4, 5)-trisphosphate (PIP3). If PI-3,4-P2 is a positive effector, INPP4B would be a negative regulator of PI3K signaling, and there is some evidence to support this. Utilizing phosphatase and tensin homolog deleted on chromosome ten (PTEN)-null triple-negative breast tumor cell lines, it was unexpectedly found that silencing INPP4B decreased basal phospho-Akt (pAkt) and cellular proliferation, and in most cases sensitized cells to PI3K-α and PI3K-β isoform-specific inhibitors. Conversely, overexpression of INPP4B desensitized cells to PI3K inhibitors in a phosphatase activity-dependent manner. In summary, the current investigation of INPP4B in PTEN-null TNBC suggests new mechanistic insight and the potential for targeted therapy for this aggressive subset of breast cancer.Implications: These data support a model where PI-3,4-P2 is inhibitory toward PI3K, revealing a novel feedback mechanism under conditions of excessive signaling, and potentially an indication for PI3K-β isoform-specific inhibitors in PTEN-null TNBC that have lost INPP4B expression. Mol Cancer Res; 15(6); 765-75. ©2017 AACR.
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Affiliation(s)
- Darien E Reed
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California.,Howard Hughes Medical Institute, University of California, San Francisco, California
| | - Kevan M Shokat
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California. .,Howard Hughes Medical Institute, University of California, San Francisco, California
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Lu M, Zessin AS, Glover W, Hsu DS. Activation of the mTOR Pathway by Oxaliplatin in the Treatment of Colorectal Cancer Liver Metastasis. PLoS One 2017; 12:e0169439. [PMID: 28060954 PMCID: PMC5218497 DOI: 10.1371/journal.pone.0169439] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 12/16/2016] [Indexed: 11/18/2022] Open
Abstract
Background Standard of care treatment for colorectal cancer liver metastasis consists of a cytotoxic chemotherapy in combination with a targeted agent. Clinical trials have guided the use of these combinatory therapies, but it remains unclear what the optimal combinations of cytotoxic chemotherapy with a targeted agent are. Methods Using a genomic based approach, gene expression profiling was obtained from tumor samples of patient with colorectal cancer liver metastasis who received an oxaliplatin based therapy. Early passaged colorectal cancer liver metastasis cell lines and patient derived xenografts of colorectal cancer liver metastasis were then treated with oxaliplatin and a mTOR inhibitor. Results Gene set enrichment analysis revealed that the mTOR pathway was activated in patients receiving oxaliplatin based therapy. Treatment of early passaged colorectal cancer lines and patient derived xenografts with oxaliplatin resulted in activation of the mTOR pathway. Combination therapy with oxaliplatin and a mTOR inhibitor resulted in a synergistic effect both in vitro and in vivo. Conclusion Our findings suggest a genomic based approach can be used to identify optimal combinations of cytotoxic chemotherapy with a targeted agent and that these observations can be validated both in vitro and in vivo using patient derived colorectal cancer cell lines and patient derived xenografts prior to clinical use.
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Affiliation(s)
- Min Lu
- Department of Medical Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
- Center for Genomics and Computational Biology, Duke University, Durham, North Carolina, United States of America
| | - Amelia S. Zessin
- Department of Medical Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Wayne Glover
- Department of Medical Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
- Center for Genomics and Computational Biology, Duke University, Durham, North Carolina, United States of America
| | - David S. Hsu
- Department of Medical Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
- Center for Genomics and Computational Biology, Duke University, Durham, North Carolina, United States of America
- * E-mail:
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Zhang J, Jiang W, Liu W, Wu JJ, Song L, Cheng JX, Yao M, Yang LP, Yao DF. Effective targeting of colorectal cancer cells using TORC1/2 kinase inhibitors in vitro and in vivo. Future Oncol 2016; 12:515-24. [PMID: 26776341 DOI: 10.2217/fon.15.248] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Aim: We investigated the effects of TORC1/2 kinase inhibitors on colorectal cancer (CRC) cell lines. Materials & methods: Using selective TORC1/2 inhibitors, rapamycin and PP242, we assessed their effect on the growth of CRC cells in vitro and tumor growth in vivo. Results: Rapamycin and PP242 inhibit proliferation and induce apoptosis of CRC cells. They also enhance proapoptotic effect of conventional chemo drug doxorubicin in CRC cells in vitro. When combined with doxorubicin, rapamycin and PP242 almost completely inhibit tumor growth in vivo. Rapamycin and PP242 inhibit phosphorylation of Akt, ribosomal S6 kinase, 4EBP1 and mTOR. Conclusion: Our study suggests rapamycin and PP242 may be a useful therapeutic agent and inhibiting mTOR signaling pathway represents a new targeted therapy for CRC.
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Affiliation(s)
- Jie Zhang
- The Affiliated Hospital of Nantong University, Nantong 226001, China
- School of Medicine, Nantong University, Nantong 226019, China
| | - Wen Jiang
- Department of Internal Medicine, The Third People's Hospital of Nantong, Nantong 226001, China
| | - Wei Liu
- Department of Orthopedics, The Second Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Juan-Juan Wu
- School of Medicine, Nantong University, Nantong 226019, China
| | - Lei Song
- Department of Paediatrics, The Second Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Ji-Xian Cheng
- Department of Oncological Surgery, The Third Affiliated Hospital of Wenzhou Medical University, Wenzhou 325001, China
| | - Ming Yao
- The Affiliated Hospital of Nantong University, Nantong 226001, China
| | - Li-Ping Yang
- School of Medicine, Nantong University, Nantong 226019, China
| | - Deng-Fu Yao
- The Affiliated Hospital of Nantong University, Nantong 226001, China
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Maletzki C, Huehns M, Knapp P, Waukosin N, Klar E, Prall F, Linnebacher M. Functional Characterization and Drug Response of Freshly Established Patient-Derived Tumor Models with CpG Island Methylator Phenotype. PLoS One 2015; 10:e0143194. [PMID: 26618628 PMCID: PMC4664421 DOI: 10.1371/journal.pone.0143194] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 11/02/2015] [Indexed: 12/16/2022] Open
Abstract
Patient-individual tumor models constitute a powerful platform for basic and translational analyses both in vitro and in vivo. However, due to the labor-intensive and highly time-consuming process, only few well-characterized patient-derived cell lines and/or corresponding xenografts exist. In this study, we describe successful generation and functional analysis of novel tumor models from patients with sporadic primary colorectal carcinomas (CRC) showing CpG island methylator phenotype (CIMP). Initial DNA fingerprint analysis confirmed identity with the patient in all four cases. These freshly established cells showed characteristic features associated with the CIMP-phenotype (HROC40: APCwt, TP53 mut, KRAS mut; 3/8 marker methylated; HROC43: APC mut, TP53 mut, KRAS mut; 4/8 marker methylated; HROC60: APCwt, TP53 mut, KRASwt; 4/8 marker methylated; HROC183: APC mut, TP53 mut, KRAS mut; 6/8 marker methylated). Cell lines were of epithelial origin (EpCAM+) with distinct morphology and growth kinetics. Response to chemotherapeutics was quite individual between cells, with stage I-derived cell line HROC60 being most susceptible towards standard clinically approved chemotherapeutics (e.g. 5-FU, Irinotecan). Of note, most cell lines were sensitive towards "non-classical" CRC standard drugs (sensitivity: Gemcitabin > Rapamycin > Nilotinib). This comprehensive analysis of tumor biology, genetic alterations and assessment of chemosensitivity towards a broad range of (chemo-) therapeutics helps bringing forward the concept of personalized tumor therapy.
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Affiliation(s)
- Claudia Maletzki
- Molecular Oncology and Immunotherapy, University of Rostock, Rostock, Germany
| | - Maja Huehns
- Institute of Pathology, University of Rostock, Rostock, Germany
| | - Patrick Knapp
- Molecular Oncology and Immunotherapy, University of Rostock, Rostock, Germany
| | - Nancy Waukosin
- Molecular Oncology and Immunotherapy, University of Rostock, Rostock, Germany
| | - Ernst Klar
- Department of General Surgery, University of Rostock, Rostock, Germany
| | - Friedrich Prall
- Institute of Pathology, University of Rostock, Rostock, Germany
| | - Michael Linnebacher
- Molecular Oncology and Immunotherapy, University of Rostock, Rostock, Germany
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Yang D, Qu J, Qu X, Cao Y, Xu L, Hou K, Feng W, Liu Y. Gossypol sensitizes the antitumor activity of 5-FU through down-regulation of thymidylate synthase in human colon carcinoma cells. Cancer Chemother Pharmacol 2015. [PMID: 26208739 DOI: 10.1007/s00280-015-2749-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE 5-Fluorouracil (5-FU) is the basic chemotherapeutic agent used to treat colon cancer. However, the sensitivity of colon cancer cells to 5-FU is limited. Gossypol is a polyphenolic extract of cottonseeds. The purpose of this study was to investigate the activities and related mechanism of gossypol alone or in combination with 5-FU against human colon carcinoma cells. METHODS The IC50 of gossypol or/and 5-FU in vitro was tested by 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, and the drug interaction was analyzed using the CalcuSyn method. Cell apoptosis was determined using presidium iodide staining and flow cytometric analysis. Western blotting was used to determine the expression of proteins. Transient transfection method was used to silence protein. RESULTS The IC₅₀ at 48 h of gossypol in colon cancer cells was 26.11 ± 1.04 μmol/L in HT-29 cells, 14.11 ± 1.08 μmol/L in HCT116 cells, and 21.83 ± 1.05 μmol/L in RKO cells. When gossypol was combined with 5-FU, a synergistic cytotoxic effect was observed in HT-29 cells, HCT116 cells, and RKO cells compared with treatment with gossypol or 5-FU alone. The Western blotting results indicated that gossypol down-regulated thymidylate synthase (TS) rather than thymidine phosphorylase protein expression. Furthermore, the mTOR/p70S6K1 signaling pathway was inhibited in gossypol-treated colon cancer cells, and consequently, cyclin D1 expression was decreased, suggesting an additional mechanism of the observed antiproliferative synergistic interactions. All the observation was confirmed by silencing TS and inactivating the mTOR/p70S6K1 signaling pathway by rapamycin, both of which increased the chemo-sensitizing efficacy of 5-FU. CONCLUSIONS These findings suggest that gossypol-mediated down-regulation of TS, cyclin D1, and the mTOR/p70S6K1 signaling pathways enhances the anti-tumor effect of 5-FU. Ultimately, our data exposed a new action for gossypol as an enhancer of 5-FU-induced cell growth suppression.
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Affiliation(s)
- Dan Yang
- Department of Pharmacology, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang City, 110122, People's Republic of China
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Maletzki C, Gock M, Randow M, Klar E, Huehns M, Prall F, Linnebacher M. Establishment and characterization of cell lines from chromosomal instable colorectal cancer. World J Gastroenterol 2015; 21:164-176. [PMID: 25574089 PMCID: PMC4284332 DOI: 10.3748/wjg.v21.i1.164] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/26/2014] [Accepted: 07/24/2014] [Indexed: 02/06/2023] Open
Abstract
AIM To generate novel tumor models for preclinical validation of biomarkers that allow drug response prediction and individual therapeutic decisions. METHODS Cell line establishment was conducted by both direct in vitro culturing and in vivo xenografting followed by in vitro culturing procedure. A comprehensive characterization was subsequently performed. This included quality control, consisting of the confirmation of human and colorectal cancer (CRC) origin by DNA fingerprint and epithelial cell adhesion molecule (EpCAM) staining, as well as mycoplasma and human virus testing. Phenotypic analysis was done by light microscopy and multicolor flow cytometry. Histopathological examination (β-catenin and cytokeratin staining) was conducted in direct comparison to parental tumor tissues. Extensive molecular-pathological profiling included mutation analysis for CRC-associated driver mutations, assessment of chromosomal and microsatellite instability, and the grade of CpG island methylation. Additionally, an array-based comparative genomic hybridization analysis was performed. Drug responsiveness was assessed for a panel of classical and novel substances in clinical use for the treatment of solid cancers. Finally, tumorigenicity of the cell lines was tested by xenografting into immunocompromised nude mice. RESULTS Herein we describe the establishment of three ultra-low passage cell lines from two individual patients suffering from sporadic CRC. One cell line was derived directly from an early stage case (HROC18), whereas two cell lines could be established both direct from patient material and after xenografting from a late stage tumor (HROC32). All cell lines were free of contaminating mycoplasma and viruses. Molecular-pathological analysis allowed all cell lines to be classified as chromosomal instable (CIN(+)). They were aneuploid, with CpG island promoter methylation and microsatellite instability being absent. The following mutational profile was observed both in the cell lines and the parental tumor tissue: HROC18: APC(mut), p53(mut), K-ras(wt); HROC32: APC(wt), p53(mut), K-ras(mut). All cell lines were characterized as epithelial (EpCAM(+)) cells, showing distinct morphology and migration speed, but comparable growth kinetics. The cell lines showed different patterns of response towards clinically approved and novel drugs, with HROC18 being more resistant than HROC32 cells. Finally, in vivo tumorigenicity was demonstrated. CONCLUSION We successfully established and characterized novel ultra-low passage patient-derived CRC models as useful instruments for analyzing biological characteristics associated with the CIN(+) phenotype.
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Chiarini F, Evangelisti C, McCubrey JA, Martelli AM. Current treatment strategies for inhibiting mTOR in cancer. Trends Pharmacol Sci 2014; 36:124-35. [PMID: 25497227 DOI: 10.1016/j.tips.2014.11.004] [Citation(s) in RCA: 213] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 11/07/2014] [Accepted: 11/12/2014] [Indexed: 02/07/2023]
Abstract
Mammalian target of rapamycin (mTOR) is a Ser/Thr kinase that regulates a wide range of functions, including cell growth, proliferation, survival, autophagy, metabolism, and cytoskeletal organization. mTOR activity is dysregulated in several human disorders, including cancer. The crucial role of mTOR in cancer cell biology has stimulated interest in mTOR inhibitors, placing mTOR on the radar of the pharmaceutical industry. Several mTOR inhibitors have already undergone clinical trials for treating tumors, without great success, although mTOR inhibitors are approved for the treatment of some types of cancer, including advanced renal cell carcinoma. However, the role of mTOR inhibitors in cancer treatment continues to evolve as new compounds are continuously being disclosed. Here we review the three classes of mTOR inhibitors currently available for treating cancer patients. Moreover, we highlight efforts to identify markers of resistance and sensitivity to mTOR inhibition that could prove useful in the emerging field of personalized medicine.
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Affiliation(s)
- Francesca Chiarini
- Institute of Molecular Genetics, National Research Council, Bologna, Italy; Rizzoli Orthopedic Institute, Bologna, Italy
| | - Camilla Evangelisti
- Institute of Molecular Genetics, National Research Council, Bologna, Italy; Rizzoli Orthopedic Institute, Bologna, Italy
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Alberto M Martelli
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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Wang XW, Zhang YJ. Targeting mTOR network in colorectal cancer therapy. World J Gastroenterol 2014; 20:4178-88. [PMID: 24764656 PMCID: PMC3989954 DOI: 10.3748/wjg.v20.i15.4178] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/28/2013] [Accepted: 01/20/2014] [Indexed: 02/06/2023] Open
Abstract
The mechanistic target of rapamycin (mTOR) integrates growth factor signals with cellular nutrient and energy levels and coordinates cell growth, proliferation and survival. A regulatory network with multiple feedback loops has evolved to ensure the exquisite regulation of cell growth and division. Colorectal cancer is the most intensively studied cancer because of its high incidence and mortality rate. Multiple genetic alterations are involved in colorectal carcinogenesis, including oncogenic Ras activation, phosphatidylinositol 3-kinase pathway hyperactivation, p53 mutation, and dysregulation of wnt pathway. Many oncogenic pathways activate the mTOR pathway. mTOR has emerged as an effective target for colorectal cancer therapy. In vitro and preclinical studies targeting the mTOR pathway for colorectal cancer chemotherapy have provided promising perspectives. However, the overall objective response rates in major solid tumors achieved with single-agent rapalog therapy have been modest, especially in advanced metastatic colorectal cancer. Combination regimens of mTOR inhibitor with agents such as cytotoxic chemotherapy, inhibitors of vascular endothelial growth factor, epidermal growth factor receptor and Mitogen-activated protein kinase kinase (MEK) inhibitors are being intensively studied and appear to be promising. Further understanding of the molecular mechanism in mTOR signaling network is needed to develop optimized therapeutic regimens. In this paper, oncogenic gene alterations in colorectal cancer, as well as their interaction with the mTOR pathway, are systematically summarized. The most recent preclinical and clinical anticancer therapeutic endeavors are reviewed. New players in mTOR signaling pathway, such as non-steroidal anti-inflammatory drug and metformin with therapeutic potentials are also discussed here.
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Abstract
mTOR [mammalian (or mechanistic) target of rapamycin] is a protein kinase that, as part of mTORC1 (mTOR complex 1), acts as a critical molecular link between growth signals and the processes underlying cell growth. Although there has been intense interest in the upstream mechanisms regulating mTORC1, the full repertoire of downstream molecular events through which mTORC1 signalling promotes cell growth is only recently coming to light. It is now recognized that mTORC1 promotes cell growth and proliferation in large part through the activation of key anabolic processes. Through a variety of downstream targets, mTORC1 alters cellular metabolism to drive the biosynthesis of building blocks and macromolecules fundamentally essential for cell growth, including proteins, lipids and nucleic acids. In the present review, we focus on the metabolic functions of mTORC1 as they relate to the control of cell growth and proliferation. As mTORC1 is aberrantly activated in a number of tumour syndromes and up to 80% of human cancers, we also discuss the importance of this mTORC1-driven biosynthetic programme in tumour growth and progression.
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Cai Z, Ke J, He X, Yuan R, Chen Y, Wu X, Wang L, Wang J, Lan P, Wu X. Significance of mTOR signaling and its inhibitor against cancer stem-like cells in colorectal cancer. Ann Surg Oncol 2013; 21:179-88. [PMID: 23907312 DOI: 10.1245/s10434-013-3146-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Indexed: 12/15/2022]
Abstract
PURPOSE To determine the role of the mammalian target of rapamycin (mTOR) signaling in sustaining cancer stem-like cells and its clinical values in colorectal cancer (CRC). METHODS mTOR expression in CRC patients was analyzed by immunohistochemistry and survival analysis was used to confirm the clinical value of mTOR. Colorectal cell lines were treated by mTOR inhibitors rapamycin and PP242, and sphere formation assay and aldehyde dehydrogenase (ALDH) assay were utilized to determine the impact of mTOR inhibition in CRC stem-like cells, combined or not combined with chemotherapeutic drug (fluorouracil and oxaliplatin). RESULTS mTOR expression was associated with outcomes of CRC patients and predicted poor prognosis in stage II CRC patients. mTOR signaling was activated in stem-like colorectal cancer cells, and mTOR inhibitors (rapamycin and PP242) decreased the capacity of sphere formation as well as ALDH activity. Furthermore, mTOR inhibitors also were demonstrated to suppress the stimulation of stem-like cells by chemotherapy. CONCLUSIONS mTOR shared predictive significance in stage II CRC patients' outcomes and played a vital role in the maintenance of colorectal cancer stem-like cells. mTOR inhibitors might hold the potential to become a therapeutic target against CRC stem cells.
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Affiliation(s)
- Zerong Cai
- Department of Colorectal Surgery, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, People's Republic of China
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Ducker GS, Atreya CE, Simko JP, Hom YK, Matli MR, Benes CH, Hann B, Nakakura EK, Bergsland EK, Donner DB, Settleman J, Shokat KM, Warren RS. Incomplete inhibition of phosphorylation of 4E-BP1 as a mechanism of primary resistance to ATP-competitive mTOR inhibitors. Oncogene 2013; 33:1590-600. [PMID: 23542178 PMCID: PMC3982880 DOI: 10.1038/onc.2013.92] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 12/19/2012] [Accepted: 01/25/2013] [Indexed: 12/12/2022]
Abstract
The mammalian target of rapamycin (mTOR) regulates cell growth by integrating nutrient and growth factor signaling and is strongly implicated in cancer. But mTOR is not an oncogene, and which tumors will be resistant or sensitive to new ATP-competitive mTOR inhibitors now in clinical trials remains unknown. We screened a panel of over 600 human cancer cell lines to identify markers of resistance and sensitivity to the mTOR inhibitor PP242. RAS and PIK3CA mutations were the most significant genetic markers for resistance and sensitivity to PP242, respectively; colon origin was the most significant marker for resistance based on tissue type. Among colon cancer cell lines, those with KRAS mutations were most resistant to PP242, while those without KRAS mutations most sensitive. Surprisingly, cell lines with co-mutation of PIK3CA and KRAS had intermediate sensitivity. Immunoblot analysis of the signaling targets downstream of mTOR revealed that the degree of cellular growth inhibition induced by PP242 was correlated with inhibition of phosphorylation of the translational repressor 4E-BP1, but not ribosomal protein S6. In a tumor growth inhibition trial of PP242 in patient-derived colon cancer xenografts, resistance to PP242 induced inhibition of 4E-BP1 phosphorylation and xenograft growth was again observed in KRAS mutant tumors without PIK3CA co-mutation, compared to KRAS WT controls. We show that, in the absence of PIK3CA co-mutation, KRAS mutations are associated with resistance to PP242 and that this is specifically linked to changes in the level of phosphorylation of 4E-BP1.
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Affiliation(s)
- G S Ducker
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA
| | - C E Atreya
- Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - J P Simko
- Department of Pathology, University of California, San Francisco, San Francisco, CA, USA
| | - Y K Hom
- 1] Preclinical Therapeutics Core, University of California, San Francisco, San Francisco, CA, USA [2] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - M R Matli
- 1] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA [2] Section of Surgical Oncology, Department of Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - C H Benes
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA
| | - B Hann
- 1] Preclinical Therapeutics Core, University of California, San Francisco, San Francisco, CA, USA [2] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - E K Nakakura
- 1] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA [2] Section of Surgical Oncology, Department of Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - E K Bergsland
- Department of Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - D B Donner
- 1] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA [2] Section of Surgical Oncology, Department of Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - J Settleman
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA
| | - K M Shokat
- 1] Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA [2] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA [3] Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
| | - R S Warren
- 1] Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA [2] Section of Surgical Oncology, Department of Surgery, University of California, San Francisco, San Francisco, CA, USA
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