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Durinck K, Goossens S, Peirs S, Wallaert A, Van Loocke W, Matthijssens F, Pieters T, Milani G, Lammens T, Rondou P, Van Roy N, De Moerloose B, Benoit Y, Haigh J, Speleman F, Poppe B, Van Vlierberghe P. Novel biological insights in T-cell acute lymphoblastic leukemia. Exp Hematol 2015; 43:625-39. [PMID: 26123366 DOI: 10.1016/j.exphem.2015.05.017] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Accepted: 05/24/2015] [Indexed: 01/07/2023]
Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive type of blood cancer that accounts for about 15% of pediatric and 25% of adult acute lymphoblastic leukemia (ALL) cases. It is considered as a paradigm for the multistep nature of cancer initiation and progression. Genetic and epigenetic reprogramming events, which transform T-cell precursors into malignant T-ALL lymphoblasts, have been extensively characterized over the past decade. Despite our comprehensive understanding of the genomic landscape of human T-ALL, leukemia patients are still treated by high-dose multiagent chemotherapy, potentially followed by hematopoietic stem cell transplantation. Even with such aggressive treatment regimens, which are often associated with considerable acute and long-term side effects, about 15% of pediatric and 40% of adult T-ALL patients still relapse, owing to acquired therapy resistance, and present with very dismal survival perspectives. Unfortunately, the molecular mechanisms by which residual T-ALL tumor cells survive chemotherapy and act as a reservoir for leukemic progression and hematologic relapse remain poorly understood. Nevertheless, it is expected that enhanced molecular understanding of T-ALL disease biology will ultimately facilitate a targeted therapy driven approach that can reduce chemotherapy-associated toxicities and improve survival of refractory T-ALL patients through personalized salvage therapy. In this review, we summarize recent biological insights into the molecular pathogenesis of T-ALL and speculate how the genetic landscape of T-ALL could trigger the development of novel therapeutic strategies for the treatment of human T-ALL.
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Affiliation(s)
- Kaat Durinck
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Steven Goossens
- Department for Biomedical Molecular Biology, Ghent University, Ghent, Belgium; Unit for Molecular Oncology, VIB Inflammation Research Center, Ghent, Belgium; Mammalian Functional Genetics Laboratory, Division of Blood Cancers, Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia
| | - Sofie Peirs
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Annelynn Wallaert
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Wouter Van Loocke
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | | | - Tim Pieters
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium; Department for Biomedical Molecular Biology, Ghent University, Ghent, Belgium; Unit for Molecular Oncology, VIB Inflammation Research Center, Ghent, Belgium
| | - Gloria Milani
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Tim Lammens
- Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium
| | - Pieter Rondou
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Nadine Van Roy
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Barbara De Moerloose
- Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium
| | - Yves Benoit
- Department of Pediatric Hematology-Oncology and Stem Cell Transplantation, Ghent University Hospital, Ghent, Belgium
| | - Jody Haigh
- Mammalian Functional Genetics Laboratory, Division of Blood Cancers, Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia
| | - Frank Speleman
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
| | - Bruce Poppe
- Center for Medical Genetics, Department for Pediatrics, Ghent, Belgium
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Huang Z, Wu Y, Zhou X, Qian J, Zhu W, Shu Y, Liu P. Clinical efficacy of mTOR inhibitors in solid tumors: a systematic review. Future Oncol 2015; 11:1687-99. [PMID: 26043220 DOI: 10.2217/fon.15.70] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
ABSTRACT The common dysregulation of the mTOR signaling pathway in tumor cells makes it a key target in oncotherapy. To better understand the effects of mTOR inhibitors, we analyzed 32 published clinical trials on solid tumors other than renal cell cancer, neuroendocrine tumors and metastatic breast cancer, for mTOR inhibitors are already approved by the US FDA to treat the three cancers. A lack of therapeutic effects was observed when mTOR inhibitors were used as a single agent. When combined with other agents, mTOR inhibitors still lacked sufficient clinical activity or just had minimal activity. More studies are required to better understand the clinically effects of mTOR inhibitors and the development of novel mTOR inhibitors is absolutely necessary.
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Affiliation(s)
- Zebo Huang
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029, People's Republic of China
| | - Yinxia Wu
- Department of Oncology, Clinical Medical College of Yangzhou University, No 98 Nantong Western Road, Yangzhou 225001, People's Republic of China
| | - Xin Zhou
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029, People's Republic of China
| | - Jiaqi Qian
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029, People's Republic of China
| | - Wei Zhu
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029, People's Republic of China
| | - Yongqian Shu
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029, People's Republic of China
| | - Ping Liu
- Department of Oncology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing 210029, People's Republic of China
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103
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Fazolini NPB, Cruz ALS, Werneck MBF, Viola JPB, Maya-Monteiro CM, Bozza PT. Leptin activation of mTOR pathway in intestinal epithelial cell triggers lipid droplet formation, cytokine production and increased cell proliferation. Cell Cycle 2015; 14:2667-76. [PMID: 26017929 PMCID: PMC4614828 DOI: 10.1080/15384101.2015.1041684] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Accumulating evidence suggests that obesity and enhanced inflammatory reactions are predisposing conditions for developing colon cancer. Obesity is associated with high levels of circulating leptin. Leptin is an adipocytokine that is secreted by adipose tissue and modulates immune response and inflammation. Lipid droplets (LD) are organelles involved in lipid metabolism and production of inflammatory mediators, and increased numbers of LD were observed in human colon cancer. Leptin induces the formation of LD in macrophages in a PI3K/mTOR pathway-dependent manner. Moreover, the mTOR is a serine/threonine kinase that plays a key role in cellular growth and is frequently altered in tumors. We therefore investigated the role of leptin in the modulation of mTOR pathway and regulation of lipid metabolism and inflammatory phenotype in intestinal epithelial cells (IEC-6 cells). We show that leptin promotes a dose- and time-dependent enhancement of LD formation. The biogenesis of LD was accompanied by enhanced CXCL1/CINC-1, CCL2/MCP-1 and TGF-β production and increased COX-2 expression in these cells. We demonstrated that leptin-induced increased phosphorylation of STAT3 and AKT and a dose and time-dependent mTORC activation with enhanced phosphorilation of the downstream protein P70S6K protein. Pre-treatment with rapamycin significantly inhibited leptin effects in LD formation, COX-2 and TGF-β production in IEC-6 cells. Moreover, leptin was able to stimulate the proliferation of epithelial cells on a mTOR-dependent manner. We conclude that leptin regulates lipid metabolism, cytokine production and proliferation of intestinal cells through a mechanism largely dependent on activation of the mTOR pathway, thus suggesting that leptin-induced mTOR activation may contribute to the obesity-related enhanced susceptibility to colon carcinoma.
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Affiliation(s)
- Narayana P B Fazolini
- a Laboratory of Immunopharmacology; Oswaldo Cruz Institute; FIOCRUZ ; Rio de Janeiro , Brazil
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104
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Influence of Rictor and Raptor Expression of mTOR Signaling on Long-Term Outcomes of Patients with Hepatocellular Carcinoma. Dig Dis Sci 2015; 60:919-28. [PMID: 25371154 DOI: 10.1007/s10620-014-3417-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 10/27/2014] [Indexed: 12/11/2022]
Abstract
BACKGROUND Aberrant signaling mediated by the mammalian target of rapamycin (mTOR) occurs at high frequency in hepatocellular carcinoma (HCC), indicating that mTOR is a candidate for targeted therapy. mTOR forms two complexes called mTORC1 (mTOR complexed with raptor) and mTORC2 (mTOR complexed with rictor). There are minor studies of the expression kinetics of mTORC1 and mTORC2 in HCC. METHODS We studied 62 patients with HCC who underwent curative resection. We used univariate and multivariate analyses to identify factors that potentially influence disease and overall survival after hepatectomy. The mRNA and protein levels of mTOR, rictor and raptor in cancer and non-cancer tissues were analyzed using quantitative RT-PCR, immunohistochemistry and Western blotting. RESULTS/CONCLUSION High ratio of the levels of rictor and raptor mRNAs in tumors was identified as independent prognostic indicators for disease-free survival. Low and high levels of preoperative serum albumin and mTOR mRNA in the tumor, respectively, were identified as independent indicators of overall survival. HCC is likely to recur early after hepatic resection in patients with high levels of mTOR and rictor mRNAs and high rictor/raptor ratios in cancer tissues. We conclude that analysis of mTOR expression in cancer tissues represents an essential strategy to predict HCC recurrence after curative treatment.
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105
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Lin F, de Gooijer MC, Hanekamp D, Brandsma D, Beijnen JH, van Tellingen O. Targeting core (mutated) pathways of high-grade gliomas: challenges of intrinsic resistance and drug efflux. CNS Oncol 2015; 2:271-88. [PMID: 25054467 DOI: 10.2217/cns.13.15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
High-grade gliomas are the most common type of primary brain tumor and are among the most lethal types of human cancer. Most patients with a high-grade glioma have glioblastoma multiforme (GBM), the most malignant glioma subtype that is associated with a very aggressive disease course and short overall survival. Standard treatment of newly diagnosed GBM involves surgery followed by chemoradiation with temozolomide. However, despite this extensive treatment the mean overall survival is still only 14.6 months and more effective treatments are urgently needed. Although different types of GBMs are indistinguishable by histopathology, novel molecular pathological techniques allow discrimination between the four main GBM subtypes. Targeting the aberrations in the molecular pathways underlying these subtypes is a promising strategy to improve therapy. In this article, we will discuss the potential avenues and pitfalls of molecularly targeted therapies for the treatment of GBM.
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Affiliation(s)
- Fan Lin
- Department of Clinical Chemistry/Preclinical Pharmacology, The Netherlands Cancer Institute/Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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Tumor cells switch to mitochondrial oxidative phosphorylation under radiation via mTOR-mediated hexokinase II inhibition--a Warburg-reversing effect. PLoS One 2015; 10:e0121046. [PMID: 25807077 PMCID: PMC4373728 DOI: 10.1371/journal.pone.0121046] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 01/27/2015] [Indexed: 01/24/2023] Open
Abstract
A unique feature of cancer cells is to convert glucose into lactate to produce cellular energy, even under the presence of oxygen. Called aerobic glycolysis [The Warburg Effect] it has been extensively studied and the concept of aerobic glycolysis in tumor cells is generally accepted. However, it is not clear if aerobic glycolysis in tumor cells is fixed, or can be reversed, especially under therapeutic stress conditions. Here, we report that mTOR, a critical regulator in cell proliferation, can be relocated to mitochondria, and as a result, enhances oxidative phosphorylation and reduces glycolysis. Three tumor cell lines (breast cancer MCF-7, colon cancer HCT116 and glioblastoma U87) showed a quick relocation of mTOR to mitochondria after irradiation with a single dose 5 Gy, which was companied with decreased lactate production, increased mitochondrial ATP generation and oxygen consumption. Inhibition of mTOR by rapamycin blocked radiation-induced mTOR mitochondrial relocation and the shift of glycolysis to mitochondrial respiration, and reduced the clonogenic survival. In irradiated cells, mTOR formed a complex with Hexokinase II [HK II], a key mitochondrial protein in regulation of glycolysis, causing reduced HK II enzymatic activity. These results support a novel mechanism by which tumor cells can quickly adapt to genotoxic conditions via mTOR-mediated reprogramming of bioenergetics from predominantly aerobic glycolysis to mitochondrial oxidative phosphorylation. Such a “waking-up” pathway for mitochondrial bioenergetics demonstrates a flexible feature in the energy metabolism of cancer cells, and may be required for additional cellular energy consumption for damage repair and survival. Thus, the reversible cellular energy metabolisms should be considered in blocking tumor metabolism and may be targeted to sensitize them in anti-cancer therapy.
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107
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AZD-4547 exerts potent cytostatic and cytotoxic activities against fibroblast growth factor receptor (FGFR)-expressing colorectal cancer cells. Tumour Biol 2015; 36:5641-8. [PMID: 25691251 DOI: 10.1007/s13277-015-3237-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 02/06/2015] [Indexed: 01/02/2023] Open
Abstract
Colorectal cancer (CRC) causes significant mortalities worldwide. Fibroblast growth factor (FGF) receptor (FGFR) signaling is frequently dysregulated and/or constitutively activated in CRCs, contributing to cancer carcinogenesis and progression. Here, we studied the activity of AZD-4547, a novel and potent FGFR kinase inhibitor, on CRC cells. AZD-4547 inhibited CRC cell growth in vitro, and its activity correlated with the FGFR-1/2 expression level. AZD-4547 was cytotoxic and pro-apoptotic in FGFR-1/2-expressed CRC cell lines (NCI-H716 and HCT-116), but not in FGFR-1/2 null HT-29 cells. Further, AZD-4547 inhibited cell cycle progression and attenuated the activation of FGFR1-FGFR substrate 2 (FRS-2), ERK/mitogen-activated protein kinase (MAPK), and AKT/mammalian target of rapamycin (AKT/mTOR) signalings in NCI-H716 and HCT-116 cells. In vivo, AZD-4547 oral administration at effective doses inhibited NCI-H716 (high FGFR-1/2 expression) xenograft growth in nude mice. Phosphorylation of FGFR-1, AKT, and ERK1/2 in xenograft specimens was also inhibited by AZD-4547 administration. Thus, our preclinical studies strongly support possible clinical investigations of AZD-4547 for the treatment of CRCs harboring deregulated FGFR signalings.
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108
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Zheng R, Huang Y, Ma X. [Antiproliferative effect of silencing mTOR gene on MCL Jeko-1 cell line and its mechanism]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2015; 36:49-52. [PMID: 25641147 PMCID: PMC7343038 DOI: 10.3760/cma.j.issn.0253-2727.2015.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To investigate the effect of silencing mTOR gene by RNA interference on proliferation and apoptosis, and its mechanism on mantle cell lymphoma Jeko-1 cell Line. METHODS The hairpin-like oligonucleotide sequences targeting mTOR gene was designed and transfected into Jeko-1 cells by lipofectamine TM 2000. The mTOR mRNA and protein were detected by RQ-PCR and Western blot. Cell growth was determined by MTT. Cell apoptosis was analyzed by flow cytometry. The expressions of Bcl-2, Bax, procaspase-3, procaspase-9, P70S6K,and p-P70S6K were detected by Western blot. RESULTS mTOR mRNA was markedly suppressed by shRNA targeting mTOR. mTOR shRNA suppressed proliferation and induced cells apoptosis of Jeko-1 cells. The cell apoptotic rates were (36.62 ± 3.24)%, (2.58 ± 1.04)%, (1.24 ± 0.30)% respectively, in mTOR shRNA, Neg-shRNA and Blank with statistically significant difference among them (P<0.05). mTOR shRNA down-regulated the expressions of Bcl-2, proCaspase3, proCaspase9 and p-70S6K, up-regulated the expression of Bax. CONCLUSION Deplete of mTOR gene may be realized through inhibiting the Akt/mTOR signaling pathway to promote the cell apoptosis and inhibit cell growth in Jeko-1 cell line.
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Affiliation(s)
- Ruiji Zheng
- Department of Hematology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou 363000, Fujian Province, China
| | - Yiqun Huang
- Department of Hematology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou 363000, Fujian Province, China
| | - Xudong Ma
- Department of Hematology, Zhangzhou Affiliated Hospital of Fujian Medical University, Zhangzhou 363000, Fujian Province, China
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109
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Abstract
Using the immune system to control cancer has been investigated for over a century. Yet it is only over the last several years that therapeutic agents acting directly on the immune system have demonstrated improved overall survival for cancer patients in phase III clinical trials. Furthermore, it appears that some patients treated with such agents have been cured of metastatic cancer. This has led to increased interest and acceleration in the rate of progress in cancer immunotherapy. Most of the current immunotherapeutic success in cancer treatment is based on the use of immune-modulating antibodies targeting critical checkpoints (CTLA-4 and PD-1/PD-L1). Several other immune-modulating molecules targeting inhibitory or stimulatory pathways are being developed. The combined use of these medicines is the subject of intense investigation and holds important promise. Combination regimens include those that incorporate targeted therapies that act on growth signaling pathways, as well as standard chemotherapy and radiation therapy. In fact, these standard therapies have intrinsic immune-modulating properties that can support antitumor immunity. In the years ahead, adoptive T-cell therapy will also be an important part of treatment for some cancer patients. Other areas which are regaining interest are the use of oncolytic viruses that immunize patients against their own tumors and the use of vaccines against tumor antigens. Immunotherapy has demonstrated unprecedented durability in controlling multiple types of cancer and we expect its use to continue expanding rapidly.
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110
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Modulators of cellular senescence: mechanisms, promises, and challenges from in vitro studies with dietary bioactive compounds. Nutr Res 2014; 34:1017-35. [DOI: 10.1016/j.nutres.2014.02.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 02/24/2014] [Accepted: 02/26/2014] [Indexed: 12/11/2022]
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111
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112
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Teixeira C, Vale N, Pérez B, Gomes A, Gomes JRB, Gomes P. "Recycling" classical drugs for malaria. Chem Rev 2014; 114:11164-220. [PMID: 25329927 DOI: 10.1021/cr500123g] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Cátia Teixeira
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal.,CICECO, Departamento de Química, Universidade de Aveiro , P-3810-193 Aveiro, Portugal
| | - Nuno Vale
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
| | - Bianca Pérez
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
| | - Ana Gomes
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
| | - José R B Gomes
- CICECO, Departamento de Química, Universidade de Aveiro , P-3810-193 Aveiro, Portugal
| | - Paula Gomes
- Centro de Investigação em Química da Universidade do Porto, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , P-4169-007 Porto, Portugal
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113
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D’Angelo L, Piazzi G, Pacilli A, Prossomariti A, Fazio C, Montanaro L, Graziani G, Fogliano V, Munarini A, Bianchi F, Belluzzi A, Bazzoli F, Ricciardiello L. A combination of eicosapentaenoic acid-free fatty acid, epigallocatechin-3-gallate and proanthocyanidins has a strong effect on mTOR signaling in colorectal cancer cells. Carcinogenesis 2014; 35:2314-20. [DOI: 10.1093/carcin/bgu173] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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114
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Kira S, Tabata K, Shirahama-Noda K, Nozoe A, Yoshimori T, Noda T. Reciprocal conversion of Gtr1 and Gtr2 nucleotide-binding states by Npr2-Npr3 inactivates TORC1 and induces autophagy. Autophagy 2014; 10:1565-78. [PMID: 25046117 PMCID: PMC4206535 DOI: 10.4161/auto.29397] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Autophagy is an intracellular degradation process that delivers cytosolic material to
lysosomes and vacuoles. To investigate the mechanisms that regulate autophagy, we
performed a genome-wide screen using a yeast deletion-mutant collection, and found that
Npr2 and Npr3 mutants were defective in autophagy. Their mammalian homologs, NPRL2 and
NPRL3, were also involved in regulation of autophagy. Npr2-Npr3 function upstream of
Gtr1-Gtr2, homologs of the mammalian RRAG GTPase complex, which is crucial for TORC1
regulation. Both npr2∆ mutants and a GTP-bound Gtr1 mutant suppressed
autophagy and increased Tor1 vacuole localization. Furthermore, Gtr2 binds to the TORC1
subunit Kog1. A GDP-bound Gtr1 mutant induced autophagy even under nutrient-rich
conditions, and this effect was dependent on the direct binding of Gtr2 to Kog1. These
results revealed that 2 molecular mechanisms, Npr2-Npr3-dependent GTP hydrolysis of Gtr1
and direct binding of Gtr2 to Kog1, are involved in TORC1 inactivation and autophagic
induction.
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Affiliation(s)
- Shintaro Kira
- Center for Frontier Oral Science; Graduate School of Dentistry; Osaka University, Osaka, Japan; Graduate School of Frontier Bioscience; Osaka University; Osaka, Japan
| | - Keisuke Tabata
- Laboratory of Viral Infection; International Research Center for Infectious Diseases; Research Institute for Microbial Diseases; Osaka University; Osaka, Japan
| | - Kanae Shirahama-Noda
- Center for Frontier Oral Science; Graduate School of Dentistry; Osaka University, Osaka, Japan
| | - Akiko Nozoe
- Graduate School of Medicine, Osaka University; Osaka, Japan
| | - Tamotsu Yoshimori
- Graduate School of Frontier Bioscience; Osaka University; Osaka, Japan; Graduate School of Medicine, Osaka University; Osaka, Japan
| | - Takeshi Noda
- Center for Frontier Oral Science; Graduate School of Dentistry; Osaka University, Osaka, Japan; Graduate School of Frontier Bioscience; Osaka University; Osaka, Japan
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115
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Schenone S, Radi M, Musumeci F, Brullo C, Botta M. Biologically Driven Synthesis of Pyrazolo[3,4-d]pyrimidines As Protein Kinase Inhibitors: An Old Scaffold As a New Tool for Medicinal Chemistry and Chemical Biology Studies. Chem Rev 2014; 114:7189-238. [DOI: 10.1021/cr400270z] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Silvia Schenone
- Dipartimento
di Farmacia, Università degli Studi di Genova Viale Benedetto
XV, 3, 16132 Genova, Italy
| | - Marco Radi
- Dipartimento
di Farmacia, Università degli Studi di Parma Viale delle
Scienze, 27/A, 43124 Parma, Italy
| | - Francesca Musumeci
- Dipartimento
di Farmacia, Università degli Studi di Genova Viale Benedetto
XV, 3, 16132 Genova, Italy
| | - Chiara Brullo
- Dipartimento
di Farmacia, Università degli Studi di Genova Viale Benedetto
XV, 3, 16132 Genova, Italy
| | - Maurizio Botta
- Dipartimento
di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena Via Aldo Moro, 2, 53100 Siena, Italy
- Sbarro
Institute for Cancer Research and Molecular Medicine, Center for Biotechnology,
College of Science and Technology, Temple University, BioLife Science
Building, Suite 333, 1900 N 12th Street, Philadelphia, Pennsylvania 19122, United States
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116
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Tapia O, Riquelme I, Leal P, Sandoval A, Aedo S, Weber H, Letelier P, Bellolio E, Villaseca M, Garcia P, Roa JC. The PI3K/AKT/mTOR pathway is activated in gastric cancer with potential prognostic and predictive significance. Virchows Arch 2014; 465:25-33. [PMID: 24844205 DOI: 10.1007/s00428-014-1588-4] [Citation(s) in RCA: 147] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 03/31/2014] [Accepted: 04/28/2014] [Indexed: 12/13/2022]
Abstract
Signaling pathway alterations are important in the development of gastric cancer (GC). Deregulation of the PI3K/AKT/mTOR pathway plays a crucial role in the regulation of multiple cellular functions including cell growth, proliferation, metabolism, and angiogenesis. Our goal was to assess expression of proteins involved in the PI3K/AKT/mTOR pathway by immunohistochemistry (IHC) in tumor and nontumor gastric mucosa from patients with advanced GC. We evaluated 71 tumor and 71 nontumor gastric mucosa samples from advanced GC patients, selected from Hernán Henríquez Aravena Hospital (Temuco, Chile). The targets studied were PI3K, AKT, p-AKT, PTEN, mTOR, p-mTOR, P70S6K1, p-P70S6K1, 4E-BP1, p-4E-BP1, eIF4E, and p-eIF4E. Expression data were correlated with clinicomorphological data. Descriptive and analytical statistics were used (95 % confidence interval, p < 0.05). For survival analyses, the Kaplan-Meier method and the log-rank test were used. PI3K, AKT, p-AKT, p-mTOR, p-4E-BP1, P70S6K1, p-P70S6K1, eIF-4E, and p-eIF-4E proteins were significantly overexpressed in tumor tissue. Conversely, PTEN was underexpressed in tumor tissue, notably in pT3-pT4 tumors (p = 0.02) and tumors with lymph node metastases (p < 0.001). P70S6K1 expression was associated with pT3-pT4 tumors (p = 0.03). Moreover, PI3K (p = 0.004), AKT (p = 0.01), p-AKT (p = 0.01), P70S6K1 (p = 0.04), p-P70S6K1 (p = 0.001), and eIF-4E (p = 0.004) were overexpressed in tumors with lymph node metastases. Low expression of 4E-BP1 was associated with poor overall survival (p = 0.03). Our results suggest that the PI3K/AKT/mTOR pathway is activated in GC, with overexpression in tumor tissue of most of the studied proteins (total and phosphorylated). These might be considered as target for specific targeted therapy in GC.
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Affiliation(s)
- Oscar Tapia
- Department of Pathology, Universidad de La Frontera, CEGIN-BIOREN, Temuco, Chile
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117
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Eyre TA, Collins GP, Goldstone AH, Cwynarski K. Time now to TORC the TORC? New developments in mTOR pathway inhibition in lymphoid malignancies. Br J Haematol 2014; 166:336-51. [DOI: 10.1111/bjh.12945] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 04/07/2014] [Indexed: 02/03/2023]
Affiliation(s)
- Toby A. Eyre
- Department of Haematology; Oxford University Hospitals NHS Trust; Oxford UK
| | - Graham P. Collins
- Department of Haematology; Oxford University Hospitals NHS Trust; Oxford UK
| | | | - Kate Cwynarski
- Department of Haematology; Royal Free Hospital; London UK
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Benso A, Di Carlo S, Politano G, Savino A, Vasciaveo A. An extended gene protein/products Boolean network model including post-transcriptional regulation. Theor Biol Med Model 2014; 11 Suppl 1:S5. [PMID: 25080304 PMCID: PMC4108923 DOI: 10.1186/1742-4682-11-s1-s5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background Networks Biology allows the study of complex interactions between biological systems using formal, well structured, and computationally friendly models. Several different network models can be created, depending on the type of interactions that need to be investigated. Gene Regulatory Networks (GRN) are an effective model commonly used to study the complex regulatory mechanisms of a cell. Unfortunately, given their intrinsic complexity and non discrete nature, the computational study of realistic-sized complex GRNs requires some abstractions. Boolean Networks (BNs), for example, are a reliable model that can be used to represent networks where the possible state of a node is a boolean value (0 or 1). Despite this strong simplification, BNs have been used to study both structural and dynamic properties of real as well as randomly generated GRNs. Results In this paper we show how it is possible to include the post-transcriptional regulation mechanism (a key process mediated by small non-coding RNA molecules like the miRNAs) into the BN model of a GRN. The enhanced BN model is implemented in a software toolkit (EBNT) that allows to analyze boolean GRNs from both a structural and a dynamic point of view. The open-source toolkit is compatible with available visualization tools like Cytoscape and allows to run detailed analysis of the network topology as well as of its attractors, trajectories, and state-space. In the paper, a small GRN built around the mTOR gene is used to demonstrate the main capabilities of the toolkit. Conclusions The extended model proposed in this paper opens new opportunities in the study of gene regulation. Several of the successful researches done with the support of BN to understand high-level characteristics of regulatory networks, can now be improved to better understand the role of post-transcriptional regulation for example as a network-wide noise-reduction or stabilization mechanisms.
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Yee AJ, Hari P, Marcheselli R, Mahindra AK, Cirstea DD, Scullen TA, Burke JN, Rodig SJ, Hideshima T, Laubach JP, Ghobrial IM, Schlossman RL, Munshi NC, Anderson KC, Weller EA, Richardson PG, Raje NS. Outcomes in patients with relapsed or refractory multiple myeloma in a phase I study of everolimus in combination with lenalidomide. Br J Haematol 2014; 166:401-9. [PMID: 24761838 DOI: 10.1111/bjh.12909] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 03/17/2014] [Indexed: 11/30/2022]
Abstract
Everolimus, an oral mammalian target of rapamycin (mTOR) inhibitor, has been studied in multiple myeloma (MM) but lacks significant single agent activity. Based on preclinical studies showing synergistic activity of mTOR inhibitors with lenalidomide, we studied the combination of lenalidomide and everolimus in relapsed or refractory MM in a phase I clinical trial. We assessed patient samples using gene expression, Western blotting and immunohistochemistry to probe the mTOR pathway. Twenty-six patients were evaluable for toxicity. Dose-limiting toxicities included grade 4 neutropenia and thrombocytopenia. The maximum tolerated dose was lenalidomide 15 mg and everolimus 5 mg for 21 d with a 7 d rest period. Grade 3/4 adverse events included thrombocytopenia (35%) and neutropenia (42%). The overall response rate was 65% (1 complete response + 4 partial response + 10 minimal response). The median progression-free survival was 5·5 months and median overall survival was 29·5 months. Biomarker data demonstrated downregulation of phosphorylated p70S6K. Gene expression profiling suggested activation of mTOR in responders versus non-responders. The combination of lenalidomide and everolimus was well tolerated with predictable toxicities and showed responses in a heavily pretreated population. When confirmed with larger patient numbers, this analysis may guide patient selection for future clinical trials of mTOR inhibition in MM.
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Affiliation(s)
- Andrew J Yee
- Division of Hematology and Oncology, Massachusetts General Hospital Cancer Center, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
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Rapamycin inhibition of polyposis and progression to dysplasia in a mouse model. PLoS One 2014; 9:e96023. [PMID: 24763434 PMCID: PMC3999114 DOI: 10.1371/journal.pone.0096023] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 04/02/2014] [Indexed: 01/09/2023] Open
Abstract
Familial adenomatous polyposis (FAP) is often due to adenomatous polyposis coli (APC) gene germline mutations. Somatic APC defects are found in about 80% of colorectal cancers (CRCs) and adenomas. Rapamycin inhibits mammalian target of rapamycin (mTOR) protein, which is often expressed in human adenomas and CRCs. We sought to assess the effects of rapamycin in a mouse polyposis model in which both Apc alleles were conditionally inactivated in colon epithelium. Two days after inactivating Apc, mice were given rapamycin or vehicle in cycles of two weeks on and two weeks off. Polyps were scored endoscopically. Mice were euthanized at time points or when moribund, and tissue analyses were performed. In other studies, mice with demonstrable Apc-defective colon polyps were given rapamycin, followed by analysis of their colon tissues. The median survival of mice receiving rapamycin treatment cycles was 21.5 versus 6.5 weeks in control mice (p = 0.03), and rapamycin-treated mice had a significantly lower percentage of their colon covered with polyps (4.3+/− 2 vs 56.5+/− 10.8 percent, p = 0.001). Mice with Apc-deficient colon tissues that developed high grade dysplasia treated with rapamycin underwent treatment for significantly longer than mice treated with vehicle (15.8 vs 5.1 weeks, p = 0.003). In Apc-defective colon tissues, rapamycin treatment was linked to decreased levels of β-catenin and Sox9 at 7 weeks. Other effects of rapamycin in Apc-defectivecolon tissues included decreased proliferation and increased numbers of differentiated goblet cells at 7 weeks. Rapamycin did not affect β-catenin-regulated gene expression in cultured intestinal epithelial cells. Rapamycin has potent inhibitory effects in a mouse colon polyposis model, and mTOR inhibition is linked to decreased proliferation and increased expression of differentiation markers in Apc-mutant colon epithelium and delays development of dysplasia. Our findings highlight the possibility that mTOR inhibitors may have relevance for polyposis inhibition approaches in FAP patients.
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Zhang Z, Miao L, Wu X, Liu G, Peng Y, Xin X, Jiao B, Kong X. Carnosine Inhibits the Proliferation of Human Gastric Carcinoma Cells by Retarding Akt/mTOR/p70S6K Signaling. J Cancer 2014; 5:382-9. [PMID: 24799956 PMCID: PMC4007526 DOI: 10.7150/jca.8024] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 03/10/2014] [Indexed: 12/17/2022] Open
Abstract
Carnosine (β-alanyl-L-histidine), described as an enigmatic peptide for its antioxidant, anti-aging and especially antiproliferation properties, has been demonstrated to play an anti-tumorigenic role in certain types of cancer. However, its function in human gastric carcinoma remains unclear. In this study, the effect of carnosine on cell proliferation and its underlying mechanisms were investigated in the cultured human gastric carcinoma cells. The mTOR signaling axis molecules were analyzed in carnosine treated cells. The results showed that treatment with carnosine led to proliferation inhibition, cell cycle arrest in the G0/G1 phase, apoptosis increase, and inhibition of mTOR signaling activation by decreasing the phosphorylation of Akt, mTOR and p70S6K, suggesting that proliferation inhibition of carnosine in human gastric carcinoma was through the inhibition of Akt/mTOR/p70S6K pathway, and carnosine would be a mimic of rapamycin.
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Affiliation(s)
- Zhenwei Zhang
- 1. Key Laboratory of Liver Disease, Center of Infectious Diseases, Guangzhou 458 Hospital, Guangzhou, China ; 3. Department of Biochemistry and Molecular Biology, Second Military Medical University, Shanghai, China
| | - Lei Miao
- 2. Department of Pharmacology, School of Pharmacy and Institute of Biomedical Sciences, Fudan University, Shanghai, China
| | - Xin Wu
- 1. Key Laboratory of Liver Disease, Center of Infectious Diseases, Guangzhou 458 Hospital, Guangzhou, China ; 4. Institute of Life Science and Bio-pharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
| | - Guangze Liu
- 1. Key Laboratory of Liver Disease, Center of Infectious Diseases, Guangzhou 458 Hospital, Guangzhou, China
| | - Yuting Peng
- 1. Key Laboratory of Liver Disease, Center of Infectious Diseases, Guangzhou 458 Hospital, Guangzhou, China ; 4. Institute of Life Science and Bio-pharmaceutics, Shenyang Pharmaceutical University, Shenyang, China
| | - Xiaoming Xin
- 2. Department of Pharmacology, School of Pharmacy and Institute of Biomedical Sciences, Fudan University, Shanghai, China ; 5. Department of pharmacology, Taishan Medical University, Tai'an, China
| | - Binghua Jiao
- 3. Department of Biochemistry and Molecular Biology, Second Military Medical University, Shanghai, China
| | - Xiangping Kong
- 1. Key Laboratory of Liver Disease, Center of Infectious Diseases, Guangzhou 458 Hospital, Guangzhou, China
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122
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Rapamycin inhibits Toll-like receptor 4-induced pro-oncogenic function in head and neck squamous cell carcinoma. Oncol Rep 2014; 31:2804-10. [PMID: 24737049 DOI: 10.3892/or.2014.3134] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 03/22/2014] [Indexed: 11/05/2022] Open
Abstract
Toll-like receptor 4 (TLR4) is expressed in head and neck squamous cell carcinoma (HNSCC) cells and is associated with HNSCC cancer progression. Rapamycin has been proven to be efficient for the treatment of HNSCC in vivo, yet the mechanism is not understood and rapamycin demonstrates little effect in vitro. In the present study, the HNSCC cell lines CAL27 and SCC4 were pre-treated with rapamycin then stimulated with a TLR4 ligand lipopolysaccharide (LPS). Cell proliferation, migration, invasion, resistance to TRAIL-induced apoptosis, cytokine production, NF-κB and p65 activation were determined. The results indicated that LPS significantly stimulated HNSCC cell proliferation, cytokine production, migration, invasion and resistance to apoptosis induced by tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL). Pretreatment with rapamycin significantly attenuated LPS-induced pro-oncogenic effects by inhibiting the activation of NF-κB by LPS. siRNA knockdown of TLR4 in HNSCC cells demonstrated that rapamycin attenuated LPS-induced pro-oncogenic effects via TLR4. Hence, this study suggests rapamycin may be efficient for the treatment of HNSCC by attenuating TLR4-induced pro-oncogenic effects.
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123
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Wang Y, Jia H, Lin H, Tan X, Du Z, Chen H, Xu Y, Han X, Zhang J, Zhao S, Yu X, Lu Y. Metastasis-associated gene, mag-1 improves tumour microenvironmental adaptation and potentiates tumour metastasis. J Cell Mol Med 2014; 16:3037-51. [PMID: 22985252 PMCID: PMC4393732 DOI: 10.1111/j.1582-4934.2012.01633.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 09/03/2012] [Indexed: 12/24/2022] Open
Abstract
Metastasis is a major cause of death from malignant diseases, and the underlying mechanisms are still largely not known. A detailed probe into the factors which may regulate tumour invasion and metastasis contributes to novel anti-metastatic therapies. We previously identified a novel metastasis-associated gene 1 (mag-1) by means of metastatic phenotype cloning. Then we characterized the gene expression profile of mag-1 and showed that it promoted cell migration, adhesion and invasion in vitro. Importantly, the disruption of mag-1 via RNA interference not only inhibited cellular metastatic behaviours but also significantly reduced tumour weight and restrained mouse breast cancer cells to metastasize to lungs in spontaneous metastatic assay in vivo. Furthermore, we proved that mag-1 integrates dual regulating mechanisms through the stabilization of HIF-1α and the activation of mTOR signalling pathway. We also found that mag-1-induced metastatic promotion could be abrogated by mTOR specific inhibitor, rapamycin. Taken together, the findings identified a direct role that mag-1 played in metastasis and implicated its function in cellular adaptation to tumour microenvironment.
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Affiliation(s)
- Yan Wang
- Department of Advanced Interdisciplinary Studies, Institute of Basic Medical Sciences, Beijing, China.
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A novel strategy inducing autophagic cell death in Burkitt's lymphoma cells with anti-CD19-targeted liposomal rapamycin. Blood Cancer J 2014; 4:e180. [PMID: 24510029 PMCID: PMC3944660 DOI: 10.1038/bcj.2014.2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/20/2013] [Accepted: 12/31/2013] [Indexed: 11/18/2022] Open
Abstract
Relapsed or refractory Burkitt's lymphoma often has a poor prognosis in spite of intensive chemotherapy that induces apoptotic and/or necrotic death of lymphoma cells. Rapamycin (Rap) brings about autophagy, and could be another treatment. Further, anti-CD19-targeted liposomal delivery may enable Rap to kill lymphoma cells specifically. Rap was encapsulated by anionic liposome and conjugated with anti-CD19 antibody (CD19-GL-Rap) or anti-CD2 antibody (CD2-GL-Rap) as a control. A fluorescent probe Cy5.5 was also liposomized in the same way (CD19 or CD2-GL-Cy5.5) to examine the efficacy of anti-CD19-targeted liposomal delivery into CD19-positive Burkitt's lymphoma cell line, SKW6.4. CD19-GL-Cy5.5 was more effectively uptaken into SKW6.4 cells than CD2-GL-Cy5.5 in vitro. When the cells were inoculated subcutaneously into nonobese diabetic/severe combined immunodeficiency mice, intravenously administered CD19-GL-Cy5.5 made the subcutaneous tumor fluorescent, while CD2-GL-Cy5.5 did not. Further, CD19-GL-Rap had a greater cytocidal effect on not only SKW6.4 cells but also Burkitt's lymphoma cells derived from patients than CD2-GL-Rap in vitro. The specific toxicity of CD19-GL-Rap was cancelled by neutralizing anti-CD19 antibody. The survival period of mice treated with intravenous CD19-GL-Rap was significantly longer than that of mice treated with CD2-GL-Rap after intraperitoneal inoculation of SKW6.4 cells. Anti-CD19-targeted liposomal Rap could be a promising lymphoma cell-specific treatment inducing autophagic cell death.
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125
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Bertoldo F, Silvestris F, Ibrahim T, Cognetti F, Generali D, Ripamonti CI, Amadori D, Colleoni MA, Conte P, Del Mastro L, De Placido S, Ortega C, Santini D. Targeting bone metastatic cancer: Role of the mTOR pathway. Biochim Biophys Acta Rev Cancer 2014; 1845:248-54. [PMID: 24508774 DOI: 10.1016/j.bbcan.2014.01.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 01/22/2014] [Accepted: 01/28/2014] [Indexed: 12/14/2022]
Abstract
One of the great challenges of cancer medicine is to develop effective treatments for bone metastatic cancer. Most patients with advanced solid tumors will develop bone metastasis and will suffer from skeletal related events associated with this disease. Although some therapies are available to manage symptoms derived from bone metastases, an effective treatment has not been developed yet. The mammalian target of rapamycin (mTOR) pathway regulates cell growth and survival. Alterations in mTOR signaling have been associated with pathological malignancies, including bone metastatic cancer. Inhibition of mTOR signaling might therefore be a promising alternative for bone metastatic cancer management. This review summarizes the current knowledge on mTOR pathway signaling in bone tissue and provides an overview on the known effects of mTOR inhibition in bone cancer, both in in vitro and in vivo models.
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Affiliation(s)
| | - Franco Silvestris
- Department of Biomedical Sciences and Human Oncology, Section of Clinical Oncology, University of Bari 'A. Moro', Bari, Italy
| | - Toni Ibrahim
- Osteoncology and Rare Tumors Center, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Italy
| | | | - Daniele Generali
- UO Multidisciplinare di Patologia Mammaria, US Terapia Molecolare e Farmacogenomica, AZ. Istituti Ospitalieri di Cremona, Cremona, Italy
| | - Carla Ida Ripamonti
- Supportive Care in Cancer Unit, Department of Hematology and Pediatric Onco-Hematology, Fondazione IRCCS, Istituto Nazionale dei Tumori, Milan, Italy
| | - Dino Amadori
- Osteoncology and Rare Tumors Center, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Italy
| | | | - Pierfranco Conte
- Oncologia Medica 2, Istituto Oncologico Veneto IRCCS, Padova, Italy
| | - Lucia Del Mastro
- UO Sviluppo Terapie Innovative, IRCCS AOU San Martino, IST, National Institute for Cancer Research, Genoa, Italy
| | - Sabino De Placido
- Department of Endocrinology and Molecular and Clinical Oncology, University of Naples Federico II, Naples, Italy
| | | | - Daniele Santini
- Department of Medical Oncology, University Campus Bio-Medico, Rome, Italy.
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126
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Autophagy, a novel target for chemotherapeutic intervention of thyroid cancer. Cancer Chemother Pharmacol 2013; 73:439-49. [DOI: 10.1007/s00280-013-2363-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 11/16/2013] [Indexed: 01/07/2023]
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127
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Tiwari RV, Parajuli P, Sylvester PW. γ-Tocotrienol-induced autophagy in malignant mammary cancer cells. Exp Biol Med (Maywood) 2013; 239:33-44. [PMID: 24231340 DOI: 10.1177/1535370213511022] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
γ-Tocotrienol, a member of the vitamin E family of compounds, displays potent antiproliferative and cytotoxic effects in a variety of cancer cell types at treatment doses that have little or no effect on normal cell viability or growth. Autophagy is a tightly regulated lysosomal self-digested process that can either promote cell survival or programmed cell death, but the role of autophagy in mediating γ-tocotrienol-induced cytotoxicity in breast cancer is not presently completely understood. Mouse (+SA) and human (MCF-7 and MDA-MD-231) mammary tumor cells lines were exposed to 0-40 µmol/L γ-tocotrienol for a 24 h treatment period. γ-Tocotrienol treatment caused a relatively large increase in the accumulation of monodansylcadaverine (MDC)-labeled vacuoles, a marker of autophagosome formation, in all tumor cell lines. Results also showed that γ-tocotrienol treatment induced an increased conversion of microtubule-associated protein, 1A/1B-light chain 3, from its cytosolic form (LC3B-I) to its lipidated form (LC3B-II), increased Beclin-1 levels, and increased acridine orange staining as determined by flow cytometry analysis, providing further evidence of γ-tocotrienol-induced autophagy in these mammary cancer cell lines. In contrast, similar treatment with γ-tocotrienol was not found to increase autophagy marker expression in immortalized mouse (CL-S1) and human (MCF-10 A) normal mammary epithelial cell lines. Treatment with γ-tocotrienol also caused a reduction in PI3K/Akt/mTOR signaling and a corresponding increase in the Bax/Bcl-2 ratio, cleaved caspase-3, and cleaved poly (ADP-ribose) polymerase (PARP) levels in these cancer cell lines, suggesting that γ-tocotrienol-induced autophagy may be involved in the initiation of apoptosis. In summary, these findings demonstrate that the cytotoxic effects of γ-tocotrienol are associated with the induction of autophagy in a mouse and human mammary cancer cells.
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Affiliation(s)
- Roshan V Tiwari
- College of Pharmacy, University of Louisiana at Monroe, LA 71209, USA
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Grimaldi A, Balestrieri ML, D'Onofrio N, Di Domenico G, Nocera C, Lamberti M, Tonini G, Zoccoli A, Santini D, Caraglia M, Pantano F. The synergistic effect of everolimus and chloroquine on endothelial cell number reduction is paralleled by increased apoptosis and reduced autophagy occurrence. PLoS One 2013; 8:e79658. [PMID: 24244540 PMCID: PMC3823580 DOI: 10.1371/journal.pone.0079658] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 10/03/2013] [Indexed: 12/15/2022] Open
Abstract
Endothelial Progenitor Cells (EPCs), a minor subpopulation of the mononuclear cell fraction in peripheral blood, play a critical role in cancer development as they contribute to angiogenesis-mediated pathological neovascularization. In response to tumor cytokines, including VEGF, EPCs mobilize from the bone marrow into the peripheral circulation and move to the tumor bed where they incorporate into sprouting neovessels. In the present study, we evaluated the effects of everolimus (Afinitor, Novartis), a rapamycin analogue, alone or in combination with chloroquine, a 4-alkylamino substituted quinoline family member, one of the autophagy inhibitors, on EPCs biological functions. We found that either everolimus or chloroquine induce growth inhibition on EPCs in a dose-dependent manner after 72 h from the beginning of incubation. The combined administration of the two drugs to EPC was synergistic in inducing growth inhibition; in details, the maximal pharmacological synergism between everolimus and chloroquine in inducing growth inhibition on EPCs cells was recorded when chloroquine was administered 24 h before everolimus. Moreover, we have studied the mechanisms of cell death induced by the two agents alone or in combination on EPCs and we have found that the synergistic effect of combination on EPC growth inhibition was paralleled by increased apoptosis induction and reduced autophagy. These effects occurred together with biochemical features that are typical of reduced autophagic death such as increased co-immunoprecipitation between Beclin 1 and Bcl-2. Chloroquine antagonized the inhibition of the activity of Akt→4EBP1 axis mediated by everolimus and at the same time it blocked the feed-back activation of Erk-1/2 induced by RAD in EPCs. These data suggest a new strategy in order to block angiogenesis in tumours in which this process plays a key role in both the sustainment and spreading of cancer cells.
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Affiliation(s)
- Anna Grimaldi
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy
| | - Maria Luisa Balestrieri
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy
| | - Nunzia D'Onofrio
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy
| | - Gilda Di Domenico
- Blood Transfusion Center, “S. Giovanni Bosco” of Naples, Naples, Italy
| | - Cosimo Nocera
- Blood Transfusion Center, “S. Giovanni Bosco” of Naples, Naples, Italy
| | - Monica Lamberti
- Department of Experimental Medicine, Section of Igiene, Medicina del lavoro e Medicina Legale, Second University of Naples, Naples, Italy
| | - Giuseppe Tonini
- Campus Bio-Medico University, Translational Oncology PRABB, Rome, Italy
| | - Alice Zoccoli
- Campus Bio-Medico University, Translational Oncology PRABB, Rome, Italy
| | - Daniele Santini
- Campus Bio-Medico University, Translational Oncology PRABB, Rome, Italy
| | - Michele Caraglia
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy
- * E-mail:
| | - Francesco Pantano
- Campus Bio-Medico University, Translational Oncology PRABB, Rome, Italy
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Tumour hypoxia determines the potential of combining mTOR and autophagy inhibitors to treat mammary tumours. Br J Cancer 2013; 109:2597-606. [PMID: 24157830 PMCID: PMC3833227 DOI: 10.1038/bjc.2013.644] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 09/19/2013] [Accepted: 09/24/2013] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Hypoxia can activate autophagy, a self-digest adaptive process that maintains cell turnover. Mammalian target of rapamycin (mTOR) inhibitors are used to treat cancer but also stimulate autophagy. METHODS Human mammary cancer cells and derived xenografts were used to examine whether hypoxia could exacerbate autophagy-mediated resistance to the mTOR inhibitor rapamycin. RESULTS Rapamycin exerted potent antitumour effects in MCF-7 and MDA-MB-231 mammary tumours through a marked inhibition of angiogenesis, but the autophagy inhibitor chloroquine (CQ) failed to further sensitise tumours to mTOR inhibition. Rapamycin treatment actually led to tumour reoxygenation, thereby preventing the development of autophagy. Chloroquine alone, however, blocked the growth of MCF-7 tumours and in vitro blunted the hypoxia-induced component of autophagy in these cells. Finally, when initiating CQ treatment in large, hypoxic tumours, a robust antitumour effect could be observed, which also further increased the antiproliferative effects of rapamycin. CONCLUSION The mTOR inhibitor rapamycin significantly contributes to tumour growth inhibition and normalisation of the tumour vasculature through potent antiangiogenic effects. The resulting reduction in hypoxia accounts for a lack of sensitisation by the autophagy inhibitor CQ, except if the tumours are already at an advanced stage, and thus largely hypoxic at the initiation of the combination of rapamycin and CQ treatment.
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130
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Di Carlo S, Politano G, Savino A, Benso A. A systematic analysis of a mi-RNA inter-pathway regulatory motif. J Clin Bioinforma 2013; 3:20. [PMID: 24152805 PMCID: PMC3875894 DOI: 10.1186/2043-9113-3-20] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 10/16/2013] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND The continuing discovery of new types and functions of small non-coding RNAs is suggesting the presence of regulatory mechanisms far more complex than the ones currently used to study and design Gene Regulatory Networks. Just focusing on the roles of micro RNAs (miRNAs), they have been found to be part of several intra-pathway regulatory motifs. However, inter-pathway regulatory mechanisms have been often neglected and require further investigation. RESULTS In this paper we present the result of a systems biology study aimed at analyzing a high-level inter-pathway regulatory motif called Pathway Protection Loop, not previously described, in which miRNAs seem to play a crucial role in the successful behavior and activation of a pathway. Through the automatic analysis of a large set of public available databases, we found statistical evidence that this inter-pathway regulatory motif is very common in several classes of KEGG Homo Sapiens pathways and concurs in creating a complex regulatory network involving several pathways connected by this specific motif. The role of this motif seems also confirmed by a deeper review of other research activities on selected representative pathways. CONCLUSIONS Although previous studies suggested transcriptional regulation mechanism at the pathway level such as the Pathway Protection Loop, a high-level analysis like the one proposed in this paper is still missing. The understanding of higher-level regulatory motifs could, as instance, lead to new approaches in the identification of therapeutic targets because it could unveil new and "indirect" paths to activate or silence a target pathway. However, a lot of work still needs to be done to better uncover this high-level inter-pathway regulation including enlarging the analysis to other small non-coding RNA molecules.
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Affiliation(s)
- Stefano Di Carlo
- Department of Control and Computer Engineering, Politecnico di Torino, Torino, IT, Italy
| | - Gianfranco Politano
- Department of Control and Computer Engineering, Politecnico di Torino, Torino, IT, Italy
| | - Alessandro Savino
- Consorzio Interuniversitario Nazionale per l'Informatica, Verres (AO), IT, Italy
| | - Alfredo Benso
- Department of Control and Computer Engineering, Politecnico di Torino, Torino, IT, Italy.,Consorzio Interuniversitario Nazionale per l'Informatica, Verres (AO), IT, Italy
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Altered mRNA expression related to the apoptotic effect of three xanthones on human melanoma SK-MEL-28 cell line. BIOMED RESEARCH INTERNATIONAL 2013; 2013:715603. [PMID: 24175297 PMCID: PMC3794626 DOI: 10.1155/2013/715603] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 08/09/2013] [Accepted: 08/23/2013] [Indexed: 12/20/2022]
Abstract
We previously demonstrated that α-mangostin, γ-mangostin, and 8-deoxygartanin have significant cytotoxic effects on human melanoma SK-MEL-28 cell line. The current study revealed the underlying mechanisms. α-Mangostin (7.5 μg/mL) activated caspase activity, with a 3-fold and 4-fold increased caspase 8 and 9 activity, respectively. The molecular mechanisms were investigated by qRT-PCR for mRNA related to cell cycle arrest in G1 phase (p21WAF1 and cyclin D1), apoptosis (cytochrome C, Bcl-2, and Bax), and survival pathways (Akt1, NFκB, and IκBα). α-Mangostin significantly upregulated mRNA expression of cytochrome C and p21WAF1 and downregulated that of cyclin D1, Akt1, and NFκB. γ-Mangostin significantly downregulated mRNA expression of Akt1 and NFκB and upregulated p21WAF1 and IκBα. 8-Deoxygartanin significantly upregulated the mRNA expression of p21WAF1 and downregulated that of cyclin D1 and NFκB. The three xanthones significantly inhibited the mRNA expression of the BRAF V600E mutation. Moreover, α-mangostin and γ-mangostin significantly downregulated Akt phosphorylation at Ser473. In conclusion, the three xanthones induced an inhibitory effect on SK-MEL-28 cells by modulating the molecular targets involved in the apoptotic pathways.
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Multitargeted molecular docking study of plant-derived natural products on phosphoinositide-3 kinase pathway components. Med Chem Res 2013. [DOI: 10.1007/s00044-013-0774-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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133
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O Farrell F, Rusten TE, Stenmark H. Phosphoinositide 3-kinases as accelerators and brakes of autophagy. FEBS J 2013; 280:6322-37. [PMID: 23953235 DOI: 10.1111/febs.12486] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 08/06/2013] [Accepted: 08/07/2013] [Indexed: 12/27/2022]
Abstract
Degradation of cytoplasmic material by autophagy plays a key role in protein homeostasis and metabolic control, as well as in the removal of intracellular protein aggregates, pathogens and damaged organelles. The concept of up- or down-regulating this pathway pharmacologically in neurodegenerative diseases, infections, inflammation and cancer is therefore attractive. Among the key pharmacological targets in regulation of autophagy are the phosphoinositide 3-kinases (PI3Ks), which mediate the phosphorylation of phosphatidylinositol (PtdIns) or PtdIns 4,5-bisphosphate in the 3-position of the (phospho)inositol headgroup. The catalytic products, PtdIns 3-phosphate (PtdIns3P) and PtdIns 3,4,5-trisphosphate [PtdIns(3,4,5)P3 ], respectively, have opposing roles in autophagy. PtdIns3P, the product of class II and III PI3Ks, mediates the recruitment of specific autophagic effectors to the sites of origin of autophagic membranes and thereby plays an essential role in canonical autophagy. By contrast, PtdIns(3,4,5)P3 , the product of class I PI3Ks, triggers the target of rapamycin signalling pathway, which inhibits autophagy. In this review, we discuss the functions of class I, II and III PI3Ks in autophagy and describe the protein effectors of PtdIns3P and PtdIns(3,4,5)P3 that promote or inhibit autophagy, respectively. We also provide examples of how PI3K-mediated control of autophagy is relevant to an understanding of tumour suppression and progression.
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Affiliation(s)
- Fergal O Farrell
- Centre for Cancer Biomedicine, Faculty of Medicine, Oslo University Hospital, Montebello, Norway; Department of Biochemistry, Institute for Cancer Research, Oslo University Hospital, Montebello, Norway
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Liu E, Marincola P, Öberg K. Everolimus in the treatment of patients with advanced pancreatic neuroendocrine tumors: latest findings and interpretations. Therap Adv Gastroenterol 2013; 6:412-9. [PMID: 24003341 PMCID: PMC3756638 DOI: 10.1177/1756283x13496970] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Pancreatic neuroendocrine tumors (pNETs) are a heterogeneous group of neoplasms with various clinical presentations. More than half of patients present with so-called nonfunctioning tumors with no hormone-related symptoms, whereas other tumors produce symptoms like gastric problems, ulcers, hypoglycemia, skin rash and diarrhea related to hormone production. The traditional treatment for pNETs over the last three decades has been cytotoxic agents, mainly streptozotocin plus 5-fluorouracil or doxorubicin. Most recently two new compounds have been registered worldwide for the treatment of pNETs, the mammalian target of rapamycin (mTOR) inhibitor everolimus and the tyrosine kinase inhibitor sunitinib. This paper concentrates on the use of mTOR inhibitors and the mechanisms of action. The mTOR pathway is altered in a number of pNETs. Everolimus (RAD001) is an orally active rapamycin analog and mTOR inhibitor. It blocks activity of the mTOR pathway by binding with high affinity to the cytoplasmic protein FKBP-12. The efficacy of everolimus in pNETs has been demonstrated in two multicenter studies (RADIANT 1 and 3). The RADIANT 3 study was a randomized controlled study in pNETs of everolimus 10 mg/day versus placebo, showing an increased progression-free survival (11.7 months versus 4.6 months) and hazard ratio of 0.35 (p < 0.001). Current studies indicate that there is strong evidence to support the antitumor effect of rapalogs in pNETs. However, significant tumor reduction is very rarely obtained, usually in less than 10% of treated patients. Therefore, these drugs may be more effective in combination with other anticancer agents, including chemotherapy, targeted therapies as well as peptide receptor radiotherapy.
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Affiliation(s)
- Eric Liu
- Department of Surgery, Surgical Oncology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Paula Marincola
- Department of Surgery, Surgical Oncology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Kjell Öberg
- Department of Medical Sciences, Uppsala University, Entrance 40, 5th floor, SE-751 85 Uppsala, Sweden
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Jiang X, Wang G, Liu R, Wang Y, Wang Y, Qiu X, Gao X. RNase non-sensitive and endocytosis independent siRNA delivery system: delivery of siRNA into tumor cells and high efficiency induction of apoptosis. NANOSCALE 2013; 5:7256-7264. [PMID: 23812036 DOI: 10.1039/c3nr01183f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
To date, RNase degradation and endosome/lysosome trapping are still serious problems for siRNA-based molecular therapy, although different kinds of delivery formulations have been tried. In this report, a cell penetrating peptide (CPP, including a positively charged segment, a linear segment, and a hydrophobic segment) and a single wall carbon nanotube (SWCNT) are applied together by a simple method to act as a siRNA delivery system. The siRNAs first form a complex with the positively charged segment of CPP via electrostatic forces, and the siRNA-CPP further coats the surface of the SWCNT via hydrophobic interactions. This siRNA delivery system is non-sensitive to RNase and can avoid endosome/lysosome trapping in vitro. When this siRNA delivery system is studied in Hela cells, siRNA uptake was observed in 98% Hela cells, and over 70% mRNA of mammalian target of rapamycin (mTOR) is knocked down, triggering cell apoptosis on a significant scale. Our siRNA delivery system is easy to handle and benign to cultured cells, providing a very efficient approach for the delivery of siRNA into the cell cytosol and cleaving the target mRNA therein.
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Affiliation(s)
- Xinglu Jiang
- Department of Anatomy, Key Laboratory of Construction and Detection of Guangdong Province, Southern Medical University, Guangzhou 510515, PR China
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Kanematsu S, Tanimoto K, Suzuki Y, Sugano S. Screening for possible miRNA-mRNA associations in a colon cancer cell line. Gene 2013; 533:520-31. [PMID: 23939471 DOI: 10.1016/j.gene.2013.08.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 07/30/2013] [Accepted: 08/02/2013] [Indexed: 12/16/2022]
Abstract
MicroRNAs (miRNAs) are small non-coding RNAs mediating the regulation of gene expression in various biological contexts, including carcinogenesis. Here, we screened putative associations between 34, 45, and 103 miRNAs and 164, 391, and 81 mRNAs via Argonaute1 (Ago1) or Ago2 immunoprecipitation (IP) experiments in a colon cancer cell line. We used a combination of RIP Seq analysis. RNAs that were co-immunoprecipitated with Ago1 or Ago2 were used for massively parallel small RNA and mRNA sequencing. The detected miRNAs and mRNAs were further associated with one another based on in silico target predictions. Analysis of the putative associations indicated that, although Ago1 and Ago2 shared a similar repertory of miRNAs, the mRNAs possibly regulated by those miRNAs seemed different. The mRNAs detected with Ago1 IP were indicated to be frequently associated with genes having constitutive cellular functions, regulated by a smaller number of miRNAs, and appeared to receive more stringent translational regulation. In contrast, putative miRNA-mRNA associations detected with Ago2 IP appeared to be related to signal transduction genes, which had a larger number of possible miRNA binding sites. We then conducted a similar analysis using the colon cancer cells cultured under hypoxia and identified potential hypoxia-induced miRNA-mRNA associations, which included several well-characterized cancer-related genes as novel putative miRNA targets.
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Affiliation(s)
- Sotaro Kanematsu
- Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan
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Kim YJ, Baek E, Lee JS, Lee GM. Autophagy and its implication in Chinese hamster ovary cell culture. Biotechnol Lett 2013; 35:1753-63. [DOI: 10.1007/s10529-013-1276-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 06/07/2013] [Indexed: 12/18/2022]
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Bedford MR, Ford SJ, Horniblow RD, Iqbal TH, Tselepis C. Iron chelation in the treatment of cancer: a new role for deferasirox? J Clin Pharmacol 2013; 53:885-91. [PMID: 23740857 DOI: 10.1002/jcph.113] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 05/08/2013] [Indexed: 01/19/2023]
Abstract
Iron plays a crucial role in a number of metabolic pathways including oxygen transport, DNA synthesis, and ATP generation. Although insufficient systemic iron can result in physical impairment, excess iron has also been implicated in a number of diseases including ischemic heart disease, diabetes, and cancer. Iron chelators are agents which bind iron and facilitate its excretion. Experimental iron chelators have demonstrated potent anti-neoplastic properties in a number of cancers in vitro. These agents have yet to be translated into clinical practice, however, largely due to the significant side effects encountered in pre-clinical models. A number of licensed chelators, however, are currently in clinical use for the treatment of iron overload associated with certain non-neoplastic diseases. Deferasirox is one such agent and the drug has shown significant anti-tumor effects in a number of in vitro and in vivo studies. Deferasirox is orally administered and has demonstrated a good side effect profile in clinical practice to date. It represents an attractive agent to take forward into clinical trials of iron chelators as anti-cancer agents.
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Affiliation(s)
- Matthew R Bedford
- School of Cancer Studies, Department of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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Gao Q, Lei T, Ye F. Therapeutic targeting of EGFR-activated metabolic pathways in glioblastoma. Expert Opin Investig Drugs 2013; 22:1023-40. [PMID: 23731170 DOI: 10.1517/13543784.2013.806484] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION The highly divergent histological heterogeneities, aggressive invasion and extremely poor response to treatment make glioblastoma (GBM) one of the most lethal and difficult cancers in humans. Among key elements driving its behavior is epidermal growth factor receptor (EGFR), however, neither traditional therapy including neurosurgery, radiation, temozolomide, nor targeted EGFR therapeutics in clinic has generated promising results to date. Strategies are now focusing on blocking the downstream EGFR-activated metabolic pathways and the key phosphorylated kinases. AREAS COVERED Here, we review two major EGFR-activated downstream metabolic pathways including the PI3K/AKT/mTOR and RAS/RAF/MAPK pathways and their key phosphorylated kinase alterations in GBMs. This review also discusses potential pharmacological progress from bench work to clinical trials in order to evaluate specific inhibitors as well as therapeutics targeting PI3K and RAS signaling pathways. EXPERT OPINION Several factors impede clinical progress in targeting GBM, including the high rates of acquired resistance, heterogeneity within and across the tumors, complexity of signaling pathways and difficulty in traversing the blood-brain barrier (BBB). Substantial insight into genetic and molecular pathways and strategies to better tap the potential of these agents include rational combinatorial regimens and molecular phenotype-based patient enrichment, each of which will undoubtedly generate new therapeutic approaches to combat these devastating disabilities in the near future.
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Affiliation(s)
- Qinglei Gao
- Huazhong University of Science and Technology, Tongji Hospital, Tongji Medical College, Cancer Biology Research Center, wuhan, China
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140
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Le X, Pugach EK, Hettmer S, Storer NY, Liu J, Wills AA, DiBiase A, Chen EY, Ignatius MS, Poss KD, Wagers AJ, Langenau DM, Zon LI. A novel chemical screening strategy in zebrafish identifies common pathways in embryogenesis and rhabdomyosarcoma development. Development 2013; 140:2354-64. [PMID: 23615277 DOI: 10.1242/dev.088427] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The zebrafish is a powerful genetic model that has only recently been used to dissect developmental pathways involved in oncogenesis. We hypothesized that operative pathways during embryogenesis would also be used for oncogenesis. In an effort to define RAS target genes during embryogenesis, gene expression was evaluated in Tg(hsp70-HRAS(G12V)) zebrafish embryos subjected to heat shock. dusp6 was activated by RAS, and this was used as the basis for a chemical genetic screen to identify small molecules that interfere with RAS signaling during embryogenesis. A KRAS(G12D)-induced zebrafish embryonal rhabdomyosarcoma was then used to assess the therapeutic effects of the small molecules. Two of these inhibitors, PD98059 and TPCK, had anti-tumor activity as single agents in both zebrafish embryonal rhabdomyosarcoma and a human cell line of rhabdomyosarcoma that harbored activated mutations in NRAS. PD98059 inhibited MEK1 whereas TPCK suppressed S6K1 activity; however, the combined treatment completely suppressed eIF4B phosphorylation and decreased translation initiation. Our work demonstrates that the activated pathways in RAS induction during embryogenesis are also important in oncogenesis and that inhibition of these pathways suppresses tumor growth.
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Affiliation(s)
- Xiuning Le
- Stem Cell Program and Division of Hematology/Oncology, Children's Hospital and Dana Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 02115, USA
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Liu H, Du L, Wen Z, Yang Y, Li J, Dong Z, Zheng G, Wang L, Zhang X, Wang C. Sex determining region Y-box 2 inhibits the proliferation of colorectal adenocarcinoma cells through the mTOR signaling pathway. Int J Mol Med 2013; 32:59-66. [PMID: 23599173 DOI: 10.3892/ijmm.2013.1354] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 04/12/2013] [Indexed: 11/06/2022] Open
Abstract
Sex determining region Y-box 2 (SOX2), is a high mobility group box transcription factor involved in the maintenance of pluripotency and the self-renewal of embryonic and neuronal stem cells, which also plays differential roles in the cell proliferation of several tumors. However, its role in colorectal adenocarcinoma cell proliferation and the underlying mechanisms remain unclear. The mammalian target of rapamycin (mTOR) signaling pathway has recently emerged as an important regulator of cell proliferation in many types of cancer. In this study, we examined the effect of SOX2 on the proliferation of colorectal adenocarcinoma cells and evaluated the role of the mTOR pathway in this process. Our results indicated that the overexpression of SOX2 significantly inhibited the proliferation of colorectal adenocarcinoma cells. Of note, mechanistic investigations revealed that SOX2 inhibited the activation of the mTOR pathway in HT-29 cells. We then examined the effect of SOX2 on the cell cycle, and the results revealed that SOX2 downregulated cyclin D1 expression and induced G0/G1 arrest in the HT-29 cells. Moreover, we also analyzed the correlation between SOX2 expression and patient clinicopathological characteristics in colorectal adenocarcinoma tissues, as well as the level of phospho-S6 (S235/236), phospho-Akt (S473) and cyclin D1. The results revealed a significant negative correlation between SOX2 expression and tumor size and the levels of phospho-S6 (S235/236), phospho-Akt (S473) and cyclin D1. Taken together, to our knowledge, our findings suggest for the first time that SOX2 suppresses colorectal adenocarcinoma cell proliferation through the inhibition of the mTOR pathway.
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Affiliation(s)
- Hui Liu
- Department of Clinical Laboratory, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P.R. China
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Urva S, Bouillaud E, Delaney R, Jappe A, Cheung W. A Phase I Study Evaluating the Effect of Everolimus on the Pharmacokinetics of Midazolam in Healthy Subjects. J Clin Pharmacol 2013; 53:444-50. [DOI: 10.1002/jcph.7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Accepted: 06/24/2012] [Indexed: 01/12/2023]
Affiliation(s)
- Shweta Urva
- Novartis Pharmaceuticals Corporation; Florham Park, NJ; USA
| | | | | | | | - Wing Cheung
- Novartis Pharmaceuticals Corporation; Florham Park, NJ; USA
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143
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Chou AJ, Gupta R, Bell MD, Riewe KO, Meyers PA, Gorlick R. Inhaled lipid cisplatin (ILC) in the treatment of patients with relapsed/progressive osteosarcoma metastatic to the lung. Pediatr Blood Cancer 2013; 60:580-6. [PMID: 23255417 DOI: 10.1002/pbc.24438] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 11/13/2012] [Indexed: 01/19/2023]
Abstract
BACKGROUND Osteosarcoma treatment failure is most often from the inability to control metastatic disease in the lungs. Encapsulating cisplatin within lipid complexes and delivering the agent via inhalation targets lung metastases with minimal systemic exposure. An open-label, phase Ib/IIa study was performed to characterize the safety and efficacy of inhaled lipid cisplatin (ILC) in recurrent osteosarcoma patients who only had pulmonary metastases. PROCEDURE ILC was administered via nebulizer every 2 weeks (=1 cycle). Response was evaluated radiographically every 2 cycles. Cisplatin levels were measured in patients. When possible, metastasectomy was undertaken in patients after 2 cycles. RESULTS Nineteen patients were treated. No patients experienced hematologic toxicity, nephrotoxicity or ototoxicity. Nausea/vomiting (≥grade 3) was attributed to study drug in one patient. Respiratory symptoms were observed in 13/19 patients with only one patient experiencing a ≥grade 3 respiratory symptom (not related to study drug). Systemic cisplatin exposure was minimal. Eleven patients had bulky disease, and all progressed prior to cycle 7. Eight patients had all lesions ≤2 cm. One patient had a sustained partial response. An additional two patients had stable disease after 2 cycles, underwent metastasectomy, and remained free from pulmonary recurrence 1 year after initiation of therapy. CONCLUSIONS ILC is well tolerated in heavily treated osteosarcoma patients and did not appear to have the typical toxicities associated with intravenous cisplatin. Three of eight patients with less bulky disease had sustained benefit. Further study of ILC is warranted.
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Affiliation(s)
- Alexander J Chou
- Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
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144
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Li S, Liang Y, Wu M, Wang X, Fu H, Chen Y, Wang Z. The novel mTOR inhibitor CCI-779 (temsirolimus) induces antiproliferative effects through inhibition of mTOR in Bel-7402 liver cancer cells. Cancer Cell Int 2013; 13:30. [PMID: 23537100 PMCID: PMC3632488 DOI: 10.1186/1475-2867-13-30] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 03/20/2013] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Liver cancer is one of the most frequent cancers in the world. Targeted therapy of cancer with specific inhibitors is developing and has shown promising antitumor efficacy. CCI-779 (temsirolimus), a specific inhibitor of mTOR (mammalian target of rapamycin), can block the mTOR signaling pathway. Here, we systematically examined the expression of mTOR and its downstream targets in liver cancer cells and normal liver cells, then investigated inhibitory effects of CCI-779 on mTOR signaling pathway and its role in regulating liver cancer cell growth. METHODS The expression of mTOR and its downstream targets in Bel-7402 liver cancer cells and HL-7702 normal liver cells were examined by western blot. The mTOR specific inhibitor (CCI-779) was used to treat Bel-7402 cells to identify its effects on Bel-7402 cell growth and activity of mTOR signaling pathway in vitro. Cell viability tests were performed after the treatment of CCI-779. Western blot was applied to assess the changes of mTOR pathway and flow cytometry was used to analyze cell cycle of Bel-7402 cells after the treatment of CCI-779. RESULTS mTOR, p70S6K, S6, and 4EBP1 were overexpressed in Bel-7402 cells compared with HL-7702 cells. Bel-7402 cells were sensitive to CCI-779. The survival rate of the cells treated with CCI-779 over 0.312 μM was significantly different compared with that of control (P < 0.05). CCI-779 inhibited the phosphorylation of mTOR (Ser2448), p70S6K (Thr389), S6 (Ser240/244), and 4EBP1 (Thr37/46) in different grades and the expressions of p70S6K, S6, and 4EBP1. As a result, CCI-779 induced a dose-dependent decrease in cell proliferation, G1/S arrest and damage of cell shape. CONCLUSIONS Taken together, these data showed that CCI-779 can inhibit mTOR signaling and proliferation in Bel-7402 liver cancer cells in vitro. It offers a therapeutic intervention through inhibition of mTOR as a potential strategy for liver cancer.
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Affiliation(s)
- Shuyu Li
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
| | - Yan Liang
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
| | - Manlin Wu
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
| | - Xiaojing Wang
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
| | - Haixia Fu
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
| | - Yuhao Chen
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
| | - Zhigang Wang
- College of Life Science, Inner Mongolia University, 010021, Hohhot, P.R. China
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Merlot AM, Kalinowski DS, Richardson DR. Novel chelators for cancer treatment: where are we now? Antioxid Redox Signal 2013; 18:973-1006. [PMID: 22424293 DOI: 10.1089/ars.2012.4540] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
SIGNIFICANCE Under normal circumstances, cellular iron levels are tightly regulated due to the potential toxic effects of this metal ion. There is evidence that tumors possess altered iron homeostasis, which is mediated by the perturbed expression of iron-related proteins, for example, transferrin receptor 1, ferritin and ferroportin 1. The de-regulation of iron homeostasis in cancer cells reveals a particular vulnerability to iron-depletion using iron chelators. In this review, we examine the absorption of iron from the gut; its transport, metabolism, and homeostasis in mammals; and the molecular pathways involved. Additionally, evidence for alterations in iron processing in cancer are described along with the perturbations in other biologically important transition metal ions, for example, copper(II) and zinc(II). These changes can be therapeutically manipulated by the use of novel chelators that have recently been shown to be highly effective in terms of inhibiting tumor growth. RECENT ADVANCES Such chelators include those of the thiosemicarbazone class that were originally thought to target only ribonucleotide reductase, but are now known to have multiple effects, including the generation of cytotoxic radicals. CRITICAL ISSUES Several chelators have shown marked anti-tumor activity in vivo against a variety of solid tumors. An important aspect is the toxicology and the efficacy of these agents in clinical trials. FUTURE DIRECTIONS As part of the process of the clinical assessment of the new chelators, an extensive toxicological assessment in multiple animal models is essential for designing appropriate dosing protocols in humans.
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Affiliation(s)
- Angelica M Merlot
- Department of Pathology and Bosch Institute, University of Sydney, Sydney, Australia
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146
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Thiem S, Pierce TP, Palmieri M, Putoczki TL, Buchert M, Preaudet A, Farid RO, Love C, Catimel B, Lei Z, Rozen S, Gopalakrishnan V, Schaper F, Hallek M, Boussioutas A, Tan P, Jarnicki A, Ernst M. mTORC1 inhibition restricts inflammation-associated gastrointestinal tumorigenesis in mice. J Clin Invest 2013; 123:767-81. [PMID: 23321674 DOI: 10.1172/jci65086] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 11/27/2012] [Indexed: 12/13/2022] Open
Abstract
Gastrointestinal cancers are frequently associated with chronic inflammation and excessive secretion of IL-6 family cytokines, which promote tumorigenesis through persistent activation of the GP130/JAK/STAT3 pathway. Although tumor progression can be prevented by genetic ablation of Stat3 in mice, this transcription factor remains a challenging therapeutic target with a paucity of clinically approved inhibitors. Here, we uncovered parallel and excessive activation of mTOR complex 1 (mTORC1) alongside STAT3 in human intestinal-type gastric cancers (IGCs). Furthermore, in a preclinical mouse model of IGC, GP130 ligand administration simultaneously activated mTORC1/S6 kinase and STAT3 signaling. We therefore investigated whether mTORC1 activation was required for inflammation-associated gastrointestinal tumorigenesis. Strikingly, the mTORC1-specific inhibitor RAD001 potently suppressed initiation and progression of both murine IGC and colitis-associated colon cancer. The therapeutic effect of RAD001 was associated with reduced tumor vascularization and cell proliferation but occurred independently of STAT3 activity. We analyzed the mechanism of GP130-mediated mTORC1 activation in cells and mice and revealed a requirement for JAK and PI3K activity but not for GP130 tyrosine phosphorylation or STAT3. Our results suggest that GP130-dependent activation of the druggable PI3K/mTORC1 pathway is required for inflammation-associated gastrointestinal tumorigenesis. These findings advocate clinical application of PI3K/mTORC1 inhibitors for the treatment of corresponding human malignancies.
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Affiliation(s)
- Stefan Thiem
- Ludwig Institute for Cancer Research, Melbourne-Parkville Branch, Parkville, Victoria, Australia
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Zarogoulidis P, Darwiche K, Tsakiridis K, Teschler H, Yarmus L, Zarogoulidis K, Freitag L. Learning from the Cardiologists and Developing Eluting Stents Targeting the Mtor Pathway for Pulmonary Application; A Future Concept for Tracheal Stenosis. J Mol Genet Med 2013; 7:65. [PMID: 24454525 PMCID: PMC3896392 DOI: 10.4172/1747-0862.1000065] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Tracheal stenosis due to either benign or malignant disease is a situation that the pulmonary physicians and thoracic surgeons have to cope in their everyday clinical practice. In the case where tracheal stenosis is caused due to malignancy mini-interventional interventions with laser, apc, cryoprobe, balloon dilation or with combination of more than one equipment and technique can be used. On the other hand, in the case of a benign disease such as; tracheomalacia the clinician can immediately upon diagnosis proceed to the stent placement. In both situations however; it has been observed that the stents induce formation of granuloma tissue in both or one end of the stent. Therefore a frequent evaluation of the patient is necessary, taking also into account the nature of the primary disease. Evaluation methodologies identifying different types and extent of the trachea stenosis have been previously published. However; we still do not have an effective adjuvant therapy to prevent granuloma tissue formation or prolong already treated granuloma lesions. There have been proposed many mechanisms which induce the abnormal growth of the local tissue, such as; local pressure, local stress, inflammation and vascular endothelial growth factor overexpression. Immunomodulatory agents inhibiting the mTOR pathway are capable of inhibiting the inflammatory cascade locally. In the current mini-review we will try to present the current knowledge of drug eluting stents inhibiting the mTOR pathway and propose a future application of these stents as a local anti-proliferative treatment.
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Affiliation(s)
- Paul Zarogoulidis
- Pulmonary Department-Oncology Unit, "G. Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece ; Department of Interventional Pneumology, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany
| | - Kaid Darwiche
- Department of Interventional Pneumology, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany
| | - Kosmas Tsakiridis
- Cardiothoracic Surgery Department, "Saint Luke" Private Hospital of Health Excellence, Panorama, Thessaloniki, Greece
| | - Helmut Teschler
- Pulmonary Department, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany
| | - Lonny Yarmus
- Division of Pulmonary and Critical Care Medicine, Sheikh Zayed Cardiovascular & Critical Care Tower, Johns Hopkins University, Baltimore, USA
| | - Konstantinos Zarogoulidis
- Pulmonary Department-Oncology Unit, "G. Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Lutz Freitag
- Department of Interventional Pneumology, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany
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149
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Jung EJ, Lee KY, Lee BH. Proliferating effect of orotic acid through mTORC1 activation mediated by negative regulation of AMPK in SK-Hep1 hepatocellular carcinoma cells. J Toxicol Sci 2012; 37:813-21. [PMID: 22863860 DOI: 10.2131/jts.37.813] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Orotic acid (OA) is a tumor promoter of experimental liver carcinogenesis initiated by DNA reactive carcinogens, the molecular mechanisms of which have not been fully elucidated. OA increases cell proliferation and decreases apoptosis in serum-starved SK-Hep1 hepatocellular carcinoma cells, which may ascribe to the inhibition of AMP-activated protein kinase (AMPK) phosphorylation and thus activation of mammalian target of rapamycin complex 1 (mTORC1). The effects of OA on mTORC1 activation, cell proliferation, and cell-cycle progression to S and G2/M phases were completely reversed by rapamycin. Activation of AMPK by a constitutively active mutant or aminoimidazole carboxamide ribonucleotide (AICAR) rescued the effects of OA. In conclusion, OA increases the proliferation and decreases the starvation-induced apoptosis of SK-Hep1 cells via mTORC1 activation mediated by negative regulation of AMPK.
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Affiliation(s)
- Eun-Jeong Jung
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Korea
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150
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Izumi N, Yamashita A, Ohno S. Integrated regulation of PIKK-mediated stress responses by AAA+ proteins RUVBL1 and RUVBL2. Nucleus 2012; 3:29-43. [PMID: 22540023 PMCID: PMC3337166 DOI: 10.4161/nucl.18926] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Proteins of the phosphatidylinositol 3-kinase-related protein kinase (PIKK) family are activated by various cellular stresses, including DNA damage, premature termination codon and nutritional status, and induce appropriate cellular responses. The importance of PIKK functions in the maintenance of genome integrity, accurate gene expression and the proper control of cell growth/proliferation is established. Recently, ATPase associated diverse cellular activities (AAA+) proteins RUVBL1 and RUVBL2 (RUVBL1/2) have been shown to be common regulators of PIKKs. The RUVBL1/2 complex regulates PIKK-mediated stress responses through physical interactions with PIKKs and by controlling PIKK mRNA levels. In this review, the functions of PIKKs in stress responses are outlined and the physiological significance of the integrated regulation of PIKKs by the RUVBL1/2 complex is presented. We also discuss a putative "PIKK regulatory chaperone complex" including other PIKK regulators, Hsp90 and the Tel2 complex.
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Affiliation(s)
- Natsuko Izumi
- Department of Molecular Biology, Yokohama City University School of Medicine, Yokohama, Japan
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