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Current challenges and clinical investigations of epidermal growth factor receptor (EGFR)- and ErbB family-targeted agents in the treatment of head and neck squamous cell carcinoma (HNSCC). Cancer Treat Rev 2013; 40:567-77. [PMID: 24216225 DOI: 10.1016/j.ctrv.2013.10.002] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 10/06/2013] [Indexed: 12/23/2022]
Abstract
Overexpression of the epidermal growth factor receptor (EGFR) is a common characteristic of head and neck squamous cell carcinomas (HNSCC). Cetuximab is a chimeric anti-EGFR monoclonal antibody (mAb) with multiple approved indications in HNSCC, including with radiation therapy (RT) for locoregionally advanced disease, as monotherapy after platinum progression, and with platinum/5-fluorouracil for recurrent or metastatic disease. There remain, however, numerous unanswered questions regarding the optimal use of cetuximab in HNSCC, including patient selection, its mechanisms of action and resistance, the effect of human papillomavirus status on outcomes, its role when combined with induction chemotherapy or adjuvant radiation, and optimal management of skin toxicity and hypersensitivity reactions. In addition, a variety of other anti-EGFR agents (the multitargeted small molecule tyrosine kinase inhibitors [TKIs] lapatinib, dacomitinib, and afatinib and the anti-EGFR mAbs zalutumumab, nimotuzumab, and panitumumab) are currently under investigation in phase II and III clinical trials in different HNSCC therapeutic settings. The anti-EGFR TKI erlotinib is currently in phase III development for oral cancer prevention. Numerous other drugs are in earlier stages of development for HNSCC treatment, including novel anti-EGFR mAbs (MEHD7945A, necitumumab, and RO5083945), small-molecule TKIs (vandetanib, icotinib, and CUDC-101), EGFR antisense, various add-on therapies to radiation and chemotherapy (bevacizumab, interleukin-12, lenalidomide, alisertib, and VTX-2337), and drugs (temsirolimus, everolimus, OSI-906, dasatinib, and PX-866) intended to overcome resistance to anti-EGFR agents. Overall, a wealth of clinical trial data is expected in the coming years, with the potential to modify significantly the approach to anti-EGFR therapy for HNSCC.
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Bowles DW, Ma WW, Senzer N, Brahmer JR, Adjei AA, Davies M, Lazar AJ, Vo A, Peterson S, Walker L, Hausman D, Rudin CM, Jimeno A. A multicenter phase 1 study of PX-866 in combination with docetaxel in patients with advanced solid tumours. Br J Cancer 2013; 109:1085-92. [PMID: 23942080 PMCID: PMC3778312 DOI: 10.1038/bjc.2013.474] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/23/2013] [Accepted: 07/23/2013] [Indexed: 12/31/2022] Open
Abstract
Background: This phase I, dose-finding study determined the safety, maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), pharmacokinetics, and antitumour activity of PX-866, a phosphatidylinositol 3-kinase inhibitor, combined with docetaxel in patients with incurable solid tumours. Methods: PX-866 was administered at escalating doses (4–8 mg daily) with docetaxel 75 mg m−2 intravenously every 21 days. Archived tumour tissue was assessed for potential predictive biomarkers. Results: Forty-three patients were enrolled. Most adverse events (AEs) were grade 1 or 2. The most frequent study drug-related AE was diarrhoea (76.7%), with gastrointestinal disorders occurring in 79.1% (docetaxel-related) and 83.7% (PX-866-related). No dose-limiting toxicities were observed. The RP2D was 8 mg, the same as the single-agent MTD. Co-administration of PX-866 and docetaxel did not affect either drug's PKs. Best responses in 35 evaluable patients were: 2 partial responses (6%), 22 stable disease (63%), and 11 disease progression (31%). Eleven patients remained on study for >180 days, including 8 who maintained disease control on single-agent PX-866. Overall median progression-free survival (PFS) was 73.5 days (range: 1–569). A non-significant association between longer PFS for PIK3CA-MUT/KRAS-WT vs PIK3CA-WT/KRAS-WT was observed. Conclusion: Treatment with PX-866 and docetaxel was well tolerated, without evidence of overlapping/cumulative toxicity. Further investigation with this combination is justified.
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Affiliation(s)
- D W Bowles
- Division of Medical Oncology, School of Medicine, Universitiy of Colorado, 12801 E. 17th Avenue, MS 8117, Aurora, CO 80045, USA
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Saini KS, Loi S, de Azambuja E, Metzger-Filho O, Saini ML, Ignatiadis M, Dancey JE, Piccart-Gebhart MJ. Targeting the PI3K/AKT/mTOR and Raf/MEK/ERK pathways in the treatment of breast cancer. Cancer Treat Rev 2013; 39:935-46. [PMID: 23643661 DOI: 10.1016/j.ctrv.2013.03.009] [Citation(s) in RCA: 272] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 11/24/2022]
Abstract
Alterations of signal transduction pathways leading to uncontrolled cellular proliferation, survival, invasion, and metastases are hallmarks of the carcinogenic process. The phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) and the Raf/mitogen-activated and extracellular signal-regulated kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) signaling pathways are critical for normal human physiology, and also commonly dysregulated in several human cancers, including breast cancer (BC). In vitro and in vivo data suggest that the PI3K/AKT/mTOR and Raf/MEK/ERK cascades are interconnected with multiple points of convergence, cross-talk, and feedback loops. Raf/MEK/ERK and PI3K/AKT/mTOR pathway mutations may co-exist. Inhibition of one pathway can still result in the maintenance of signaling via the other (reciprocal) pathway. The existence of such "escape" mechanisms implies that dual targeting of these pathways may lead to superior efficacy and better clinical outcome in selected patients. Several clinical trials targeting one or both pathways are already underway in BC patients. The toxicity profile of this novel approach of dual pathway inhibition needs to be closely monitored, given the important physiological role of PI3K/AKT/mTOR and Raf/MEK/ERK signaling. In this article, we present a review of the current relevant pre-clinical and clinical data and discuss the rationale for dual inhibition of these pathways in the treatment of BC patients.
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Affiliation(s)
- Kamal S Saini
- Breast International Group, Brussels, Belgium; Institut Jules Bordet, Université Libre de Bruxelles, Brussels, Belgium
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Foster JG, Blunt MD, Carter E, Ward SG. Inhibition of PI3K signaling spurs new therapeutic opportunities in inflammatory/autoimmune diseases and hematological malignancies. Pharmacol Rev 2013; 64:1027-54. [PMID: 23023033 DOI: 10.1124/pr.110.004051] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The phosphoinositide 3-kinase/mammalian target of rapamycin/protein kinase B (PI3K/mTOR/Akt) signaling pathway is central to a plethora of cellular mechanisms in a wide variety of cells including leukocytes. Perturbation of this signaling cascade is implicated in inflammatory and autoimmune disorders as well as hematological malignancies. Proteins within the PI3K/mTOR/Akt pathway therefore represent attractive targets for therapeutic intervention. There has been a remarkable evolution of PI3K inhibitors in the past 20 years from the early chemical tool compounds to drugs that are showing promise as anticancer agents in clinical trials. The use of animal models and pharmacological tools has expanded our knowledge about the contribution of individual class I PI3K isoforms to immune cell function. In addition, class II and III PI3K isoforms are emerging as nonredundant regulators of immune cell signaling revealing potentially novel targets for disease treatment. Further complexity is added to the PI3K/mTOR/Akt pathway by a number of novel signaling inputs and feedback mechanisms. These can present either caveats or opportunities for novel drug targets. Here, we consider recent advances in 1) our understanding of the contribution of individual PI3K isoforms to immune cell function and their relevance to inflammatory/autoimmune diseases as well as lymphoma and 2) development of small molecules with which to inhibit the PI3K pathway. We also consider whether manipulating other proximal elements of the PI3K signaling cascade (such as class II and III PI3Ks or lipid phosphatases) are likely to be successful in fighting off different immune diseases.
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Affiliation(s)
- John G Foster
- Inflammatory Cell Biology Laboratory, Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath, UK.
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Development of PI3K/AKT/mTOR pathway inhibitors and their application in personalized therapy for non-small-cell lung cancer. J Thorac Oncol 2012; 7:1315-26. [PMID: 22648207 DOI: 10.1097/jto.0b013e31825493eb] [Citation(s) in RCA: 154] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Lung cancer is a common disease with more than 1.6 million new cases diagnosed worldwide in 2008. Treatments for patients with advanced disease are rarely curative, and responses to therapy are often followed by relapse, which highlights the large unmet need for novel therapies. Recent advances in cancer treatment have focused on personalized therapy, whereby patients are treated with agents that best target the molecular drivers of their disease. Thus, a better understanding of the pathways that drive cancer or drug resistance is of critical importance. One such example is the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway, which is activated in many lung cancer patients and represents a target for therapy. PI3K/AKT/mTOR pathway activation has also been observed in tumors resistant to agents targeting upstream receptor tyrosine kinases. Agents that target this pathway have the potential to shut down survival pathways, and are being explored both in the setting of pathway-activating mutations and for their ability to restore sensitivity to upstream signaling targeted agents. Here, we examine the frequency of mutations activating the PI3K/AKT/mTOR pathway, review the novel agents being explored to target this pathway, and explore the potential role of the inhibition of this pathway in the clinical development of these agents.
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Phosphatidykinosital 3-Kinase and Mammalian Target of Rapamycin Pathway in Non–Small-Cell Lung Cancer. J Thorac Oncol 2012; 7:S379-82. [DOI: 10.1097/jto.0b013e31826df0f0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Sarris EG, Saif MW, Syrigos KN. The Biological Role of PI3K Pathway in Lung Cancer. Pharmaceuticals (Basel) 2012; 5:1236-64. [PMID: 24281308 PMCID: PMC3816662 DOI: 10.3390/ph5111236] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 11/07/2012] [Accepted: 11/14/2012] [Indexed: 12/31/2022] Open
Abstract
Lung cancer is the primary cause of cancer-related mortality worldwide and although improvements in treatment have been achieved over the last few years, long-term survival rates for lung cancer patients remain poor. Therefore, there is an imperative need for molecularly targeted agents that will achieve long-term disease control. Numerous downstream molecular pathways, such as EGF/RAS/RAF/MEK/ERK and PI3K/AKT/mTOR are identified as having a key role in the pathogenesis of various forms of human cancer, including lung cancer. PI3K/AKT/mTOR signal pathway is an important intracellular signal transduction pathway with a significant role in cell proliferation, growth, survival, vesicle trafficking, glucose transport, and cytoskeletal organization. Aberrations in many primary and secondary messenger molecules of this pathway, including mutations and amplifications, are accounted for tumor cell proliferation, inhibition of apoptosis, angiogenesis, metastasis and resistance to chemotherapy-radiotherapy. In this review article, we investigate thoroughly the biological role of PI3K pathway in lung cancer and its contribution in the development of future therapeutic strategies.
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Affiliation(s)
- Evangelos G. Sarris
- Oncology Unit GPP, 3rd Dept of Medicine, Sotiria General Hospital, University of Athens, Athens 11527, Greece;
| | - Muhammad W. Saif
- Experimental Therapeutics Program, Division of Hematology/Oncology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA 02111, USA;
| | - Kostas N. Syrigos
- Oncology Unit GPP, 3rd Dept of Medicine, Sotiria General Hospital, University of Athens, Athens 11527, Greece;
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Hong DS, Bowles DW, Falchook GS, Messersmith WA, George GC, O'Bryant CL, Vo ACH, Klucher K, Herbst RS, Eckhardt SG, Peterson S, Hausman DF, Kurzrock R, Jimeno A. A multicenter phase I trial of PX-866, an oral irreversible phosphatidylinositol 3-kinase inhibitor, in patients with advanced solid tumors. Clin Cancer Res 2012; 18:4173-82. [PMID: 22693357 DOI: 10.1158/1078-0432.ccr-12-0714] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE The objectives of the study were to evaluate the maximum tolerated dose (MTD), safety, pharmacodynamics, pharmacokinetics, and antitumor activity of PX-866 in patients with incurable cancers. EXPERIMENTAL DESIGN This was a phase I, open-label, dose-escalation study. Drug was administered orally once per day either on an intermittent (arm 1; days 1-5 and 8-12 of a 28-day cycle) or continuous (arm 2; days 1-28 of a 28-day cycle) schedule. Additional patients were treated at the arm 2 MTD in a food effects substudy. RESULTS Eighty-four patients were treated in the arm 1 (n = 51), arm 2 (n = 20), and food effects (n = 13) cohorts. The most frequent study drug-related adverse events were gastrointestinal disorders (69.0%), with diarrhea being the most common (48.8%). The MTD was 12 and 8 mg for arm 1 and 2, respectively. The dose-limiting toxicities (DLT) consisted of grade III diarrhea (n = 3) and grade III elevated aspartate aminotransferase (AST; n = 1). The pharmacokinetics profile was dose proportional, with no evidence of drug accumulation. PX-866-associated inhibition of platelet pAKTSER473 was observed at the arm 2 MTD. The best response per Response Evaluation Criteria in Solid Tumors (RECIST) was stable disease in 22% of evaluable patients in arm 1, 53% in arm 2, and 11% in the food effects cohort. Eight patients were on study for 4 or more months. CONCLUSIONS This first-in-human study shows that PX-866, an irreversible small-molecule inhibitor of phosphatidylinositol 3-kinase (PI3K), was well tolerated and was associated with prolonged stable disease, particularly when using a continuous dosing schedule.
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Jeong EH, Choi HS, Lee TG, Kim HR, Kim CH. Dual Inhibition of PI3K/Akt/mTOR Pathway and Role of Autophagy in Non-Small Cell Lung Cancer Cells. Tuberc Respir Dis (Seoul) 2012; 72:343-51. [PMID: 23227075 PMCID: PMC3510285 DOI: 10.4046/trd.2012.72.4.343] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Revised: 01/30/2012] [Accepted: 03/05/2012] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling axis has emerged as a novel target for cancer therapy. Agents that inhibit this pathway are currently under development for lung cancer treatment. In the present study, we have tested whether dual inhibition of PI3K/Akt/mTOR signaling can lead to enahnced antitumor effects. We have also examined the role of autophagy during this process. METHODS We analyzed the combination effect of the mTOR inhibitor, temsirolimus, and the Akt inhibitor, GSK690693, on the survival of NCI-H460 and A549 non-small cell lung cancer cells. Cell proliferation was determined by MTT assay and apoptosis induction was evaluated by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Autophagy induction was also evaluated by acridine orange staining. Changes of apoptosis or autophagy-related proteins were evaluated by western blot analysis. RESULTS Combination treatment with temsirolimus and GSK690693 caused synergistically increased cell death in NCI-H460 and A549 cells. This was attributable to increased induction of apoptosis. Caspase 3 activation and poly(ADP-ribose) polymerase cleavage accompanied these findings. Autophagy also increased and inhibition of autophagy resulted in increased cell death, suggesting its cytoprotective role during this process. CONCLUSION Taken together, our results suggest that the combination of temsirolimus and GSK690693 could be a novel strategy for lung cancer therapy. Inhibition of autophagy could also be a promising method of enhancing the combination effect of these drugs.
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Affiliation(s)
- Eun-Hui Jeong
- Division of Pulmonology, Department of Internal Medicine, Korea Cancer Center Hospital, Seoul, Korea
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DNA-PK mediates AKT activation and apoptosis inhibition in clinically acquired platinum resistance. Neoplasia 2012; 13:1069-80. [PMID: 22131882 DOI: 10.1593/neo.111032] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 09/20/2011] [Accepted: 09/23/2011] [Indexed: 01/04/2023] Open
Abstract
Clinical resistance to chemotherapy is a frequent event in cancer treatment and is closely linked to poor outcome. High-grade serous (HGS) ovarian cancer is characterized by p53 mutation and high levels of genomic instability. Treatment includes platinum-based chemotherapy and initial response rates are high; however, resistance is frequently acquired, at which point treatment options are largely palliative. Recent data indicate that platinum-resistant clones exist within the sensitive primary tumor at presentation, implying resistant cell selection after treatment with platinum chemotherapy. The AKT pathway is central to cell survival and has been implicated in platinum resistance. Here, we show that platinum exposure induces an AKT-dependent, prosurvival, DNA damage response in clinically platinum-resistant but not platinum-sensitive cells. AKT relocates to the nucleus of resistant cells where it is phosphorylated specifically on S473 by DNA-dependent protein kinase (DNA-PK), and this activation inhibits cisplatin-mediated apoptosis. Inhibition of DNA-PK or AKT, but not mTORC2, restores platinum sensitivity in a panel of clinically resistant HGS ovarian cancer cell lines: we also demonstrate these effects in other tumor types. Resensitization is associated with prevention of AKT-mediated BAD phosphorylation. Strikingly, in patient-matched sensitive cells, we do not see enhanced apoptosis on combining cisplatin with AKT or DNA-PK inhibition. Insulin-mediated activation of AKT is unaffected by DNA-PK inhibitor treatment, suggesting that this effect is restricted to DNA damage-mediated activation of AKT and that, clinically, DNA-PK inhibition might prevent platinum-induced AKT activation without interfering with normal glucose homeostasis, an unwanted toxicity of direct AKT inhibitors.
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Present and Future of EGFR Inhibitors for Head and Neck Squamous Cell Cancer. JOURNAL OF ONCOLOGY 2012; 2012:986725. [PMID: 22545054 PMCID: PMC3321461 DOI: 10.1155/2012/986725] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 01/22/2012] [Indexed: 12/11/2022]
Abstract
Although EGFR is expressed at high levels in head and neck squamous cell carcinomas (HNSCCs) and mutations are extremely rare, monotherapy with EGFR inhibitors has shown limited success. The PI3kinase/Akt pathway is responsible for cellular survival, and inhibition of phosphatidylinositol (PI) synthesis has antiproliferative, anti-invasive, and antiangiogenesis effects on HNSCC. Molecular crosstalk has been observed between EGFR and IGF1R signaling through the PI3kinase/Akt pathway in HNSCC, as has molecular crosstalk between the NFκB and STAT3 signaling pathways. Therefore, the combination of an EGFR antagonist with an agent that inhibits the activation of both Akt and NFκB may overcome resistance to EGFR antagonists in HNSCC.
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Bliesath J, Huser N, Omori M, Bunag D, Proffitt C, Streiner N, Ho C, Siddiqui-Jain A, O'Brien SE, Lim JKC, Ryckman DM, Anderes K, Rice WG, Drygin D. Combined inhibition of EGFR and CK2 augments the attenuation of PI3K-Akt-mTOR signaling and the killing of cancer cells. Cancer Lett 2012; 322:113-8. [PMID: 22387988 DOI: 10.1016/j.canlet.2012.02.032] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Revised: 02/21/2012] [Accepted: 02/23/2012] [Indexed: 11/26/2022]
Abstract
Ser/Thr protein kinase CK2 regulates multiple processes that play important roles in the sensitivity of cancer to epidermal growth factor receptor targeting therapeutics, including PI3K-Akt-mTOR signaling, Hsp90 activity, and inhibition of apoptosis. We hypothesized that top-down inhibition of EGFR, combined with lateral suppression of multiple oncogenic pathways by targeting CK2, would create a pharmacologic synthetic lethal event and result in an improved cancer therapy compared to EGFR inhibition alone. This hypothesis was tested by combining CX-4945, a first-in-class clinical stage inhibitor of CK2, with the EGFR tyrosine kinase inhibitor, erlotinib, in vitro and in vivo in models of non-small cell lung carcinoma, NCI-H2170, and squamous cell carcinoma, A431. Our results demonstrate that combination of CX-4945 with erlotinib results in enhanced attenuation of the PI3K-Akt-mTOR pathway. We also observed an increase in apoptosis, synergistic killing of cancer cells in vitro, as well as improved antitumor efficacy in vivo. Taken together, these data position CK2 as a valid pharmacologic target for drug combinations and support further evaluation of CX-4945 in combination with EGFR targeting agents.
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Abstract
The development of personalized medicine with a focus on novel targeted therapies has supplanted the one-size-fits-all approach to the treatment of many cancers, including non-small cell lung cancer. Targeted therapies, if given to a patient subpopulation enriched by the presence of relevant molecular targets, can often abrogate cell signaling that perpetuates cancer progression. Critical targets activating procancer pathways include, but are not limited to, epidermal growth factor receptor (EGFR), hepatocyte growth factor receptor (MET), vascular endothelial growth factor (VEGF), VEGF receptor, GTPase KRAS (KRAS), receptor tyrosine protein kinase erbB-2 (HER2), echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha isoform (PIK3CA), serine/threonine-protein kinase B-raf (BRAF), and insulin-like growth factor 1 receptor (IGF-1R). Some target-directed therapies, such as epidermal growth factor receptor tyrosine kinase inhibitors and anti-VEGF monoclonal antibody, have already been approved for clinical use. Others, such as those targeted to MET, VEGFR, HER2, PIK3CA, and IGF-1R, are in clinical testing. This review describes molecular targets in non-small cell lung cancer that are in development or being clinically applied and their implications for developing novel anticancer therapies for this previously refractory malignancy.
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DNA-PK mediates AKT activation and apoptosis inhibition in clinically acquired platinum resistance. Neoplasia 2011. [PMID: 22131882 DOI: 10.1593/neo.111032] [] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Clinical resistance to chemotherapy is a frequent event in cancer treatment and is closely linked to poor outcome. High-grade serous (HGS) ovarian cancer is characterized by p53 mutation and high levels of genomic instability. Treatment includes platinum-based chemotherapy and initial response rates are high; however, resistance is frequently acquired, at which point treatment options are largely palliative. Recent data indicate that platinum-resistant clones exist within the sensitive primary tumor at presentation, implying resistant cell selection after treatment with platinum chemotherapy. The AKT pathway is central to cell survival and has been implicated in platinum resistance. Here, we show that platinum exposure induces an AKT-dependent, prosurvival, DNA damage response in clinically platinum-resistant but not platinum-sensitive cells. AKT relocates to the nucleus of resistant cells where it is phosphorylated specifically on S473 by DNA-dependent protein kinase (DNA-PK), and this activation inhibits cisplatin-mediated apoptosis. Inhibition of DNA-PK or AKT, but not mTORC2, restores platinum sensitivity in a panel of clinically resistant HGS ovarian cancer cell lines: we also demonstrate these effects in other tumor types. Resensitization is associated with prevention of AKT-mediated BAD phosphorylation. Strikingly, in patient-matched sensitive cells, we do not see enhanced apoptosis on combining cisplatin with AKT or DNA-PK inhibition. Insulin-mediated activation of AKT is unaffected by DNA-PK inhibitor treatment, suggesting that this effect is restricted to DNA damage-mediated activation of AKT and that, clinically, DNA-PK inhibition might prevent platinum-induced AKT activation without interfering with normal glucose homeostasis, an unwanted toxicity of direct AKT inhibitors.
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The role of the phosphatidylinositol 3-kinase (PI3K) pathway in the development and treatment of uterine cancer. Gynecol Oncol 2011; 123:411-20. [DOI: 10.1016/j.ygyno.2011.08.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 08/03/2011] [Accepted: 08/03/2011] [Indexed: 11/19/2022]
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Abstract
Peroxisome proliferator-activated receptor-gamma (PPARγ) exerts multiple functions in determination of cell fate, tissue metabolism, and host immunity. Two synthetic PPARγ ligands (rosiglitazone and pioglitazone) were approved for the therapy of type-2 diabetes mellitus and are expected to serve as novel cures for inflammatory diseases and cancer. However, PPARγ and its ligands exhibit a janus-face behaviour as tumor modulators in various systems, resulting in either tumor suppression or tumor promotion. This may be in part due to signaling crosstalk to the mitogen-activated protein kinase (MAPK) cascades. The genomic activity of PPARγ is modulated, in addition to ligand binding, by phosphorylation of a serine residue by MAPKs, such as extracellular signal-regulated protein kinases-1/2 (ERK-1/2), or by nucleocytoplasmic compartmentalization through the ERK activators MAPK kinases-1/2 (MEK-1/2). PPARγ ligands themselves activate the ERK cascade through nongenomic and often PPARγ-independent signaling. In the current review, we discuss the molecular mechanisms and physiological implications of the crosstalk of PPARγ with MEK-ERK signaling and its potential as a novel drug target for cancer therapy in patients.
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Bowles DW, Jimeno A. New phosphatidylinositol 3-kinase inhibitors for cancer. Expert Opin Investig Drugs 2011; 20:507-18. [PMID: 21395485 DOI: 10.1517/13543784.2011.562192] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
INTRODUCTION Cancer treatment is moving away from conventional cytotoxic drugs and towards agents that target specific proteins important to cancer development or survival. The PI3K signaling axis is an important pathway involved in myriad human malignancies. Inhibition of this axis is a promising therapeutic approach for several cancers. AREAS COVERED This article reviews current literature and recent conference proceedings to analyze the rationale for targeting PI3K and its downstream effectors in cancer. Preclinical and clinical results of several PI3K and PI3K--mammalian target of rapamycin (mTOR) inhibitors in early clinical trials, as single agents and in combination with other drugs, are discussed. Thus far, clinical results have been mixed. EXPERT OPINION The clinical utility of PI3K and PI3K--mTOR inhibitors will depend on appropriate selection of patients. Mutations in the PI3K pathway may predict sensitivity to PI3K inhibition but they are not reliable biomarkers at this point. Efforts to define predictive biomarkers will probably be the key to finding therapeutic uses for this novel class of anticancer agents.
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Affiliation(s)
- Daniel W Bowles
- University of Colorado Comprehensive Cancer Center, Aurora, CO 80045, USA
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Wu D, Tao J, Xu B, Qing W, Li P, Lu Q, Zhang W. Phosphatidylinositol 3-kinase inhibitor LY294002 suppresses proliferation and sensitizes doxorubicin chemotherapy in bladder cancer cells. Urol Int 2011; 87:105-13. [PMID: 21597260 DOI: 10.1159/000322849] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 11/14/2010] [Indexed: 12/22/2022]
Abstract
BACKGROUND Phosphatidylinositol 3-kinase (PI3K)-AKT signaling is a well-characterized pathway involved in the control of cell proliferation, apoptosis and oncogenesis. LY294002 is a commonly used pharmacologic inhibitor which acts at the ATP-binding site of the PI3K enzyme, thus selectively inhibiting the PI3K-AKT nexus. The purpose of the present study was to examine whether PI3K inhibited by LY294002 had an effect on human bladder cancer cells. METHODS After treatment with LY294002, MTT assay, chemosensitivity test, colony formation assay, apoptosis assay and Western blot analysis were conducted in EJ cells. RESULT EJ cells treated with LY294002 showed significant AKT phosphorylation suppression in a dose-response manner. Also, PI3K/AKT signaling inhibitor LY294002 suppressed cell proliferation and enhanced the chemosensitivity of doxorubicin in human bladder cancer EJ cells. Furthermore, LY294002 increased cell apoptosis to doxorubicin. CONCLUSION The augmentation of doxorubicin with PI3K inhibitor LY294002 may resolve the multidrug resistance of bladder cancer, and this may be a new strategy for achieving tolerance for chemotherapeutic agents in bladder cancer therapy.
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Affiliation(s)
- Deyao Wu
- Department of Urology, First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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Role of TAPP1 and TAPP2 adaptor binding to PtdIns(3,4)P2 in regulating insulin sensitivity defined by knock-in analysis. Biochem J 2011; 434:265-74. [PMID: 21204784 DOI: 10.1042/bj20102012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Insulin sensitivity is critically dependent on the activity of PI3K (phosphoinositide 3-kinase) and generation of the PtdIns(3,4,5)P(3) second messenger. PtdIns(3,4,5)P(3) can be broken down to PtdIns(3,4)P(2) through the action of the SHIPs (Src-homology-2-domain-containing inositol phosphatases). As PtdIns(3,4)P(2) levels peak after those of PtdIns(3,4,5)P(3), it has been proposed that PtdIns(3,4)P(2) controls a negative-feedback loop that down-regulates the insulin and PI3K network. Previously, we identified two related adaptor proteins termed TAPP [tandem PH (pleckstrin homology)-domain-containing protein] 1 and TAPP2 that specifically bind to PtdIns(3,4)P(2) through their C-terminal PH domain. To determine whether TAPP1 and TAPP2 play a role in regulating insulin sensitivity, we generated knock-in mice that express normal endogenous levels of mutant TAPP1 and TAPP2 that are incapable of binding PtdIns(3,4)P(2). These homozygous TAPP1(R211L/R211L) TAPP2(R218L/R218L) double knock-in mice are viable and exhibit significantly enhanced activation of Akt, a key downstream mediator of insulin signalling. Consistent with increased PI3K and Akt activity, the double knock-in mice display enhanced whole body insulin sensitivity and disposal of glucose uptake into muscle tissues. We also generated wild-type and double TAPP1(R211L/R211L) TAPP2(R218L/R218L) knock-in embryonic fibroblasts and found that insulin triggered enhanced production of PtdIns(3,4,5)P(3) and Akt activity in the double knock-in fibroblasts. These observations provide the first genetic evidence to support the notion that binding of TAPP1 and TAPP2 adap-tors to PtdIns(3,4)P(2) function as negative regulators of the insulin and PI3K signalling pathways.
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Gwak HS, Shingu T, Chumbalkar V, Hwang YH, DeJournett R, Latha K, Koul D, Alfred Yung WK, Powis G, Farrell NP, Bögler O. Combined action of the dinuclear platinum compound BBR3610 with the PI3-K inhibitor PX-866 in glioblastoma. Int J Cancer 2011; 128:787-96. [PMID: 20473884 DOI: 10.1002/ijc.25394] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Polynuclear platinum compounds are more effective at killing glioblastoma cells than cisplatin, work by a different mechanism, and typically do not induce high levels of apoptosis at early time points after exposure. Here, we tested the hypothesis that combining BBR3610, the most potent polynuclear platinum, with a phosphoinositide-3-kinase (PI3K) inhibitor would promote apoptosis and enhance the impact on glioblastoma cells. The PI3K pathway is commonly activated in glioblastoma and promotes tumor cell survival, suggesting that its inhibition would make cells more sensitive to cytotoxic agents. We chose PX-866 as a PI3K inhibitor as it is a clinically promising agent being evaluated for brain tumor therapy. Combining BBR3610 and PX-866 resulted in synergistic killing of cultured glioma cells and an extension of survival in an orthotopic xenograft animal model. Both agents alone induced autophagy, and this appeared to be saturated, because when they were combined no additional autophagy was observed. However, the combination of PX-866 and BBR3610 did induce statistically significant increases in the level of apoptosis, associated with a reduction in pAkt and pBad, as well as inhibition of transwell migration. We conclude that combining polynuclear platinums with PI3K inhibitors has translational potential and alters the cellular response to include early apoptosis.
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Affiliation(s)
- Ho-Shin Gwak
- Department of Neurosurgery, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Wu D, Tao J, Xu B, Qing W, Li P, Lu Q, Zhang W. Phosphatidylinositol 3-kinase inhibitor LY294002 suppresses proliferation and sensitizes doxorubicin chemotherapy in bladder cancer cells. Urol Int 2011; 86:346-54. [PMID: 21273759 DOI: 10.1159/000322986] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 11/14/2010] [Indexed: 12/19/2022]
Abstract
BACKGROUND Phosphatidylinositol 3-kinase (PI3K)-AKT signaling is a well-characterized pathway involved in control of cell proliferation, apoptosis and oncogenesis. LY294002 is a commonly used pharmacologic inhibitor which acts at the ATP-binding site of the PI3K enzyme, and thus selectively inhibits the PI3K-AKT nexus. The purpose of the study was to examine whether PI3K inhibited by LY294002 had effects in human bladder cancer cells. METHODS After treatment with LY294002, MTT assay, a chemosensitivity test, colony formation assay, apoptosis assay and Western blot analysis were conducted in EJ cells. RESULT EJ cells treated with LY294002 showed significant AKT phosphorylation suppressing in a dose-response manner. Additionally, the PI3K/AKT signaling inhibitor LY294002 suppressed cell proliferation and enhanced chemosensitivity to doxorubicin in human bladder cancer EJ cells. Furthermore, LY294002 increased cell apoptosis to doxorubicin. CONCLUSION The augmentation of doxorubicin with the PI3K inhibitor LY294002 may resolve the multidrug resistance of bladder cancer, and this may be a new strategy for achieving tolerance for chemotherapeutic agents in bladder cancer therapy.
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Affiliation(s)
- Deyao Wu
- Department of Urology, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, China
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73
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Freudlsperger C, Burnett JR, Friedman JA, Kannabiran VR, Chen Z, Van Waes C. EGFR-PI3K-AKT-mTOR signaling in head and neck squamous cell carcinomas: attractive targets for molecular-oriented therapy. Expert Opin Ther Targets 2010; 15:63-74. [PMID: 21110697 DOI: 10.1517/14728222.2011.541440] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
IMPORTANCE OF THE FIELD Recent advances in the understanding of the oncogenesis of head and neck squamous cell carcinomas (HNSCC) have revealed multiple dysregulated signaling pathways. One frequently altered axis is the EGFR-PI3K-Akt-mTOR pathway. This pathway plays a central role in numerous cellular processes including metabolism, cell growth, apoptosis, survival and differentiation, which ultimately contributes to HNSCC progression. AREAS COVERED IN THIS REVIEW Books, journals, databases and websites have been searched to provide a current review on the subject. WHAT THE READER WILL GAIN This article reviews the current understanding of EGFR-PI3K-Akt-mTOR signaling in HNSCC, including the impact of both genetic and epigenetic alterations. This review further highlights the potential of targeting this signaling cascade as a promising therapeutic approach in the treatment of HNSCC. TAKE HOME MESSAGE Genetic alterations of several nodes within this pathway, including both genetic and epigenetic changes, leading to either oncogene activation or inactivation of tumor suppressors have frequently been implicated in HNSCC. Consequently, drugs that target the central nodes of this pathway have become attractive for molecular oriented cancer therapies. Numerous preclinical and clinical studies are being performed in HNSCC; however, more studies are still needed to better understand the biology of this pathway.
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Affiliation(s)
- Christian Freudlsperger
- National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Head and Neck Surgery Branch, Bethesda, MD 20892, USA
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74
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Carvalho S, Schmitt F. Potential role of PI3K inhibitors in the treatment of breast cancer. Future Oncol 2010; 6:1251-63. [DOI: 10.2217/fon.10.97] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
In recent years, we have witnessed advances in the understanding of molecular events that lead to breast cancer. This knowledge allowed, among other things, the development of novel therapies that target critical pathways involved in this disease. One of these pathways is the PI3K pathway, whose signaling axis has implications on cancer cell growth, survival, motility and metabolism. In the present review, the potential role of PI3K inhibitors in the treatment of breast cancer is discussed. The fast pace of development of these drugs urges the discussion on the advantages and pitfalls of their application and impact in the future therapy of breast cancer.
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Affiliation(s)
- Sílvia Carvalho
- Institute of Molecular Pathology & Immunology of the University of Porto, Rua Dr Roberto Frias s/n, 4200–465, Porto, Portugal
- Medical Faculty of the University of Porto, Porto, Portugal
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Cleary JM, Shapiro GI. Development of phosphoinositide-3 kinase pathway inhibitors for advanced cancer. Curr Oncol Rep 2010; 12:87-94. [PMID: 20425592 DOI: 10.1007/s11912-010-0091-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The phosphoinositide-3 kinase (PI3K) pathway plays a critical role in cancer cell growth and survival. PI3K is activated in human cancers by elevated receptor tyrosine kinase activity, RAS mutation, as well as by mutation, amplification, and deletion of genes encoding components of the pathway. Additionally, PI3K pathway activation plays an important role in acquired resistance to both chemotherapy and targeted agents. The essential role of PI3K in human cancer has led to the development of PI3K pathway inhibitors that have shown promise in preclinical models and have entered phase 1 clinical trials. This article reviews preclinical and clinical data on members of this novel drug class, as well as data justifying the combination of PI3K inhibitors with other anticancer agents.
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Affiliation(s)
- James M Cleary
- Department of Medical Oncology, Early Drug Development Center, Dana-Farber Cancer Institute, 44 Binney Street, Boston, MA, 02115, USA
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Targeted therapy in non-small-cell lung cancer--is it becoming a reality? Nat Rev Clin Oncol 2010; 7:401-14. [PMID: 20551945 DOI: 10.1038/nrclinonc.2010.64] [Citation(s) in RCA: 208] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Treatment outcomes in advanced or metastatic non-small-cell lung cancer (NSCLC) remain unsatisfactory, with low long-term survival rates. Palliative chemotherapy offers a median survival not exceeding 1 year. To date, various combinations of cytotoxic drugs have not improved treatment results beyond what has been observed with platinum doublets. By contrast, molecular targeted drugs may block important pathways that drive cancer progression and achieve long-term disease control. Conflicting results have demonstrated marginal benefit with EGFR inhibitors, anti-EGFR monoclonal antibodies and antiangiogenic strategies in unselected populations of patients with advanced NSCLC. However, patients with an EGFR mutation are likely to respond to agents that target this gene. Novel targeted therapies that interfere with insulin-like growth factor 1 receptor, or the EML4-ALK fusion protein have shown promising activity. Aberrations in other key signaling pathways and molecules, such as RAS/RAF/MEK, PI3K/AKT/mTOR, or MET kinase, have been identified as crucial targets, especially in resistant patients. Novel drugs aimed at these abnormalities are already in the clinic. This Review outlines the current state-of-the-art research for targeted therapy in NSCLC.
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Koul D, Shen R, Kim YW, Kondo Y, Lu Y, Bankson J, Ronen SM, Kirkpatrick DL, Powis G, Yung WKA. Cellular and in vivo activity of a novel PI3K inhibitor, PX-866, against human glioblastoma. Neuro Oncol 2010; 12:559-69. [PMID: 20156803 PMCID: PMC2940638 DOI: 10.1093/neuonc/nop058] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Accepted: 09/28/2009] [Indexed: 01/28/2023] Open
Abstract
The phosphatidylinositol-3-kinase (PI3K)/Akt oncogenic pathway is critical in glioblastomas. Loss of PTEN, a negative regulator of the PI3K pathway or activated PI3K/Akt pathway that drive increased proliferation, survival, neovascularization, glycolysis, and invasion is found in 70%-80% of malignant gliomas. Thus, PI3K is an attractive therapeutic target for malignant glioma. We report that a new irreversible PI3K inhibitor, PX-866, shows potent inhibitory effects on the PI3K/Akt signaling pathway in glioblastoma. PX-866 did not induce any apoptosis in glioma cells; however, an increase in autophagy was observed. PX-866 inhibited the invasive and angiogenic capabilities of cultured glioblastoma cells. In vivo, PX-866 inhibited subcutaneous tumor growth and increased the median survival time of animals with intracranial tumors. We also assessed the potential of proton magnetic resonance spectroscopy (MRS) as a noninvasive method to monitor response to PX-866. Our findings show that PX-866 treatment causes a drop in the MRS-detectable choline-to-NAA, ratio and identify this partial normalization of the tumor metabolic profile as a biomarker of molecular drug action. Our studies affirm that the PI3K pathway is a highly specific molecular target for therapies for glioblastoma and other cancers with aberrant PI3K/PTEN expression.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - W. K. Alfred Yung
- Brain Tumor Center, Department of Neuro-Oncology (D.K., R.S., Y.-W.K., Y.K., W.K.A.Y.), Department of Systems Biology (Y.L.), Department of Imaging Physics (J.B.), Department of Experimental Diagnostic Imaging (S.M.R), and Department of Experimental Therapeutics (G.P.), The University of Texas M. D. Anderson Cancer Center, Houston, Texas; Oncothyreon Inc., Seattle, Washington (D.L.K.)
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Martelli AM, Evangelisti C, Chiarini F, Grimaldi C, Manzoli L, McCubrey JA. Targeting the PI3K/AKT/mTOR signaling network in acute myelogenous leukemia. Expert Opin Investig Drugs 2010; 18:1333-49. [PMID: 19678801 DOI: 10.1517/14728220903136775] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND The PI3K/Akt/mammalian target of rapamycin (mTOR) signaling pathway plays a central role in cell growth, proliferation and survival not only under physiological conditions but also in a variety of tumor cells. Therefore, the PI3K/Akt/mTOR axis may be a critical target for cancer therapy. OBJECTIVE This review discusses how PI3K/Akt/mTOR signaling network is constitutively active in acute myelogenous leukemia (AML), where it strongly influences proliferation, survival and drug-resistance of leukemic cells, and how effective targeting of this pathway with pharmacological inhibitors, used alone or in combination with existing drugs, may result in suppression of leukemic cell growth, including leukemic stem cells. METHODS We searched the literature for articles dealing with activation of this pathway in AML and highlighting the efficacy of small molecules directed against the PI3K/Akt/mTOR signaling cascade. CONCLUSIONS The limit of acceptable toxicity for standard chemotherapy has been reached in AML. Therefore, new therapeutic strategies are needed. Targeting the PI3K/Akt/mTOR signaling network with small molecule inhibitors, alone or in combinations with other drugs, may result in less toxic and more efficacious treatment of AML patients. Efforts to exploit selective inhibitors of the PI3K/Akt/mTOR pathway that show effectiveness and safety in the clinical setting are currently underway.
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Affiliation(s)
- Alberto M Martelli
- Università di Bologna, Dipartimento di Scienze Anatomiche Umane, 40126 Bologna, Italy.
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79
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Ihle NT, Powis G. Inhibitors of phosphatidylinositol-3-kinase in cancer therapy. Mol Aspects Med 2010; 31:135-44. [PMID: 20176047 DOI: 10.1016/j.mam.2010.02.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Accepted: 02/16/2010] [Indexed: 12/30/2022]
Abstract
The phosphatidylinositol-3-kinase (PI3K) signaling pathway is implicated in multiple aspects of tumorigenesis and tumor maintenance, and recent years have seen significant efforts towards developing agents to inhibit the pathway. However, the development of such agents raises issues such as what specific member or members in the PI3K family should be inhibited to achieve maximal therapeutic benefit, and can specific inhibitors be developed with the necessary pharmacologic properties to allow them to proceed to clinical trials? The number of PI3K inhibitors has gone from a handful of archetypal inhibitors which largely determined how the pathway was initially defined through their inhibition of PI3K, but also due to their off target properties, to a much larger number of inhibitors of not only PI3K but also other members of the PI3K family. The question remains to be answered whether greater therapeutic efficacy will be obtained through the use of inhibitors with increased specificity, or through inhibitors that target a spectrum of targets within the pathway. This review will cover the development of agents targeting the pathway, and will discuss current issues surrounding the development of such agents.
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Affiliation(s)
- Nathan T Ihle
- Anderson Cancer Center, FC-6.3044, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Courtney KD, Corcoran RB, Engelman JA. The PI3K pathway as drug target in human cancer. J Clin Oncol 2010; 28:1075-83. [PMID: 20085938 PMCID: PMC2834432 DOI: 10.1200/jco.2009.25.3641] [Citation(s) in RCA: 969] [Impact Index Per Article: 69.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Accepted: 11/18/2009] [Indexed: 12/13/2022] Open
Abstract
The phosphatidylinositol 3-kinase (PI3K) signaling axis impacts on cancer cell growth, survival, motility, and metabolism. This pathway is activated by several different mechanisms in cancers, including somatic mutation and amplification of genes encoding key components. In addition, PI3K signaling may serve integral functions for noncancerous cells in the tumor microenvironment. Consequently, therapeutics targeting the PI3K pathway are being developed at a rapid pace, and preclinical and early clinical studies are beginning to suggest specific strategies to effectively use them. However, the central role of PI3K signaling in a large array of diverse biologic processes raises concerns about its use in therapeutics and increases the need to develop sophisticated strategies for its use. In this review, we will discuss how PI3K signaling affects the growth and survival of tumor cells. From this vantage, we will consider how inhibitors of the PI3K signaling cascade, either alone or in combination with other therapeutics, can most effectively be used for the treatment of cancer.
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Affiliation(s)
- Kevin D. Courtney
- From the Department of Medicine, Harvard Medical School; Department of Medical Oncology, Dana-Farber Cancer Institute; Beth Israel Deaconess Medical Center Cancer Center; Massachusetts General Hospital Cancer Center, Boston, MA
| | - Ryan B. Corcoran
- From the Department of Medicine, Harvard Medical School; Department of Medical Oncology, Dana-Farber Cancer Institute; Beth Israel Deaconess Medical Center Cancer Center; Massachusetts General Hospital Cancer Center, Boston, MA
| | - Jeffrey A. Engelman
- From the Department of Medicine, Harvard Medical School; Department of Medical Oncology, Dana-Farber Cancer Institute; Beth Israel Deaconess Medical Center Cancer Center; Massachusetts General Hospital Cancer Center, Boston, MA
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81
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Maira SM, Finan P, Garcia-Echeverria C. From the bench to the bed side: PI3K pathway inhibitors in clinical development. Curr Top Microbiol Immunol 2010; 347:209-39. [PMID: 20582534 DOI: 10.1007/82_2010_60] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A number of intracellular kinase components of the PI3K/Akt/mTOR pathway have been targeted over the past few years, leading to a new generation of anticancer agents that effectively and specifically disrupt this pathway in tumor cells. Here, progress in the identification and clinical evaluation of compounds designed to modulate the enzymatic activity of PI3K, Akt, mTOR, and Hsp90 is reviewed.
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Affiliation(s)
- Saveur-Michel Maira
- Oncology Drug Discovery, Novartis Institutes for Biomedical Research, Vitry-sur-Seine Cedex, France
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82
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Le Cras TD, Korfhagen TR, Davidson C, Schmidt S, Fenchel M, Ikegami M, Whitsett JA, Hardie WD. Inhibition of PI3K by PX-866 prevents transforming growth factor-alpha-induced pulmonary fibrosis. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 176:679-86. [PMID: 20042669 DOI: 10.2353/ajpath.2010.090123] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Transforming growth factor-alpha (TGFalpha) is a ligand for the epidermal growth factor receptor (EGFR). EGFR activation is associated with fibroproliferative processes in human lung disease and animal models of pulmonary fibrosis. EGFR signaling activates several intracellular signaling pathways including phosphatidylinositol 3'-kinase (PI3K). We previously showed that induction of lung-specific TGFalpha expression in transgenic mice caused progressive pulmonary fibrosis over a 4-week period. The increase in levels of phosphorylated Akt, detected after 1 day of doxycycline-induced TGFalpha expression, was blocked by treatment with the PI3K inhibitor, PX-866. Daily administration of PX-866 during TGFalpha induction prevented increases in lung collagen and airway resistance as well as decreases in lung compliance. Treatment of mice with oral PX-866 4 weeks after the induction of TGFalpha prevented additional weight loss and further increases in total collagen, and attenuated changes in pulmonary mechanics. These data show that PI3K is activated in TGFalpha/EGFR-mediated pulmonary fibrosis and support further studies to determine the role of PI3K activation in human lung fibrotic disease, which could be amenable to targeted therapy.
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Affiliation(s)
- Timothy D Le Cras
- Divisions of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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Paz-Ares L, Blanco-Aparicio C, García-Carbonero R, Carnero A. Inhibiting PI3K as a therapeutic strategy against cancer. Clin Transl Oncol 2009; 11:572-9. [PMID: 19775996 DOI: 10.1007/s12094-009-0407-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Class I PI3K is composed of heterodimeric lipid kinases regulating essential cellular functions including proliferation, apoptosis and metabolism. Class I PI3K isoforms are commonly amplified in different cancer types and the PI3Kalpha catalytic subunit, PIK3CA, has been found mutated in a variable proportion of tumours of different origin. Furthermore, PI3K has been shown to mediate oncogenic signalling induced by several oncogenes such as HER2 or Ras. These facts suggest that PI3K might be a good target for anticancer drug discovery. Today, the rise of PI3K inhibitors and their first in vivo results have cleared much of the path for the development of PI3K inhibitors for anticancer therapy. Here we will review the PI3K pathway and the pharmacological results of PI3K inhibition.
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Affiliation(s)
- Luis Paz-Ares
- Medical Oncology, Hospital Universitario Virgen del Rocío, Sevilla, Spain
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84
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Faller BA, Burtness B. Treatment of pancreatic cancer with epidermal growth factor receptor-targeted therapy. Biologics 2009; 3:419-28. [PMID: 19774209 PMCID: PMC2747340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Pancreatic adenocarcinoma is a common malignancy that remains refractory to available therapies. Gemcitabine has long been the standard, first-line agent in advanced disease. The epidermal growth factor receptor (EGFR) is a commonly expressed target in pancreatic cancer that is involved in tumor proliferation, metastasis, and induction of angiogenesis. The addition of the EGFR inhibitor erlotinib to gemcitabine has recently been demonstrated to provide a small, yet statistically significant, survival benefit in advanced disease. This has prompted further research into the applications of EGFR-targeted therapy in pancreatic cancer, albeit with disappointing results. Resistance to these therapies seems highly prevalent and has been implicated in their limited efficacy. The development of rash is associated with treatment efficacy and suggests that predictive factors may one day be identified to guide appropriate patient selection for these agents. Preclinical research has shown promise that resistance to EGFR-targeted therapies can be overcome through a variety of approaches. Application of this research in clinical trials may ultimately yield an unquestioned role for EGFR-targeted therapy in the management of this disease.
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Affiliation(s)
- Bryan A Faller
- Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Barbara Burtness
- Department of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA, USA
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Crouthamel MC, Kahana JA, Korenchuk S, Zhang SY, Sundaresan G, Eberwein DJ, Brown KK, Kumar R. Mechanism and management of AKT inhibitor-induced hyperglycemia. Clin Cancer Res 2009; 15:217-25. [PMID: 19118049 DOI: 10.1158/1078-0432.ccr-08-1253] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
PURPOSE Insulin-like growth factor-I receptor and phosphoinositide 3-kinase/AKT/mammalian target of rapamycin pathways are among the most active areas of drug discovery in cancer research. However, due to their integral roles in insulin signaling, inhibitors targeting these pathways often lead to hyperglycemia and hyperinsulinemia. We investigated the mechanism of hyperglycemia induced by GSK690693, a pan-AKT kinase inhibitor in clinical development, as well as methods to ameliorate these side effects. EXPERIMENTAL DESIGN The effect of GSK690693 on blood glucose, insulin, and glucagon levels was characterized in mice. We then evaluated the effects of commonly prescribed antidiabetic agents on GSK690693-induced hyperglycemia. The mechanism of blood glucose increase was evaluated using fasting and tracer uptake studies and by measuring liver glycogen levels. Finally, approaches to manage AKT inhibitor-induced hyperglycemia were designed using fasting and low carbohydrate diet. RESULTS We report that treatment with antidiabetic agents does not significantly affect GSK690693-induced hyperglycemia in rodents. However, administration of GSK690693 in mice significantly reduces liver glycogen (approximately 90%), suggesting that GSK690693 may inhibit glycogen synthesis and/or activate glycogenolysis. Consistent with this observation, fasting before drug administration reduces baseline liver glycogen levels and attenuates hyperglycemia. Further, GSK690693 also inhibits peripheral glucose uptake and introduction of a low-carbohydrate (7%) or 0% carbohydrate diet after GSK690693 administration effectively reduces diet-induced hyperglycemia in mice. CONCLUSIONS The mechanism of GSK690693-induced hyperglycemia is related to peripheral insulin resistance, increased gluconeogenesis, and/or hepatic glycogenolysis. A combination of fasting and low carbohydrate diet can reduce the magnitude of hyperglycemia induced by an AKT inhibitor.
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87
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Resistance to EGF-R (erbB-1) and VEGF-R modulating agents. Eur J Cancer 2009; 45:1117-1128. [PMID: 19124237 DOI: 10.1016/j.ejca.2008.11.038] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Revised: 11/18/2008] [Accepted: 11/20/2008] [Indexed: 12/30/2022]
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Dent P, Curiel DT, Fisher PB, Grant S. Synergistic combinations of signaling pathway inhibitors: mechanisms for improved cancer therapy. Drug Resist Updat 2009; 12:65-73. [PMID: 19395305 DOI: 10.1016/j.drup.2009.03.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 03/12/2009] [Accepted: 03/13/2009] [Indexed: 10/20/2022]
Abstract
Cancer cells contain multiple signal transduction pathways whose activities are frequently elevated due to their transformation, and that are often activated following exposure to established cytotoxic therapies including ionizing radiation and chemical DNA damaging agents. Many pathways activated in response to transformation or toxic stresses promote cell growth and invasion and counteract the processes of cell death. As a result of these findings many drugs, predominantly protein and lipid kinase inhibitors, of varying specificities, have been developed to block signaling by cell survival pathways in the hope of killing tumor cells and sensitizing them to toxic therapies. Unfortunately, due to the plasticity of signaling processes within a tumor cell, inhibition of any one growth factor receptor or signaling pathway frequently has only modest long-term effects on cancer cell viability, tumor growth, and patient survival. As a result of this realization, a greater emphasis has begun to be placed on rational combinations of drugs that simultaneously inhibit multiple inter-linked signal transduction/survival pathways. This, it is hoped, will limit the ability of tumor cells to adapt and survive because the activity within multiple parallel survival signaling pathways has been reduced. This review will discuss some of the approaches that have been taken to combine signal transduction modulatory agents to achieve enhanced tumor cell killing.
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Affiliation(s)
- Paul Dent
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, School of Medicine, 401 College St., Richmond, VA 23298, USA.
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Gustin JP, Cosgrove DP, Park BH. The PIK3CA gene as a mutated target for cancer therapy. Curr Cancer Drug Targets 2009; 8:733-40. [PMID: 19075596 DOI: 10.2174/156800908786733504] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The development of targeted therapies with true specificity for cancer relies upon exploiting differences between cancerous and normal cells. Genetic and genomic alterations including somatic mutations, translocations, and amplifications have served as recent examples of how such differences can be exploited as effective drug targets. Small molecule inhibitors and monoclonal antibodies directed against the protein products of these genetic anomalies have led to cancer therapies with high specificity and relatively low toxicity. Recently, our group and others have demonstrated that somatic mutations in the PIK3CA gene occur at high frequency in breast and other cancers. Moreover, the majority of mutations occur at three hotspots, making these ideal targets for therapeutic development. Here we review the literature on PIK3CA mutations in cancer, as well as existing data on PIK3CA inhibitors and inhibitors of downstream effectors for potential use as targeted cancer therapeutics.
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Affiliation(s)
- John P Gustin
- Department of Oncology, The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University, Baltimore, MD 21231, USA
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90
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Ihle NT, Powis G. Take your PIK: phosphatidylinositol 3-kinase inhibitors race through the clinic and toward cancer therapy. Mol Cancer Ther 2009; 8:1-9. [PMID: 19139107 DOI: 10.1158/1535-7163.mct-08-0801] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway is currently one of the most exciting drug targets in oncology. However, only a short time ago, the paradigm existed that drugs targeted to the four PI3K class I isoforms would be too toxic for use in cancer therapy due to effects on physiologic signaling. Since that time, studies have delineated the roles of these four isoforms in nonpathologic signaling as well as their roles in cancer. An extensive effort has gone into developing agents that inhibit one or more PI3K isoforms, as well as closely related proteins implicated in cancer. These agents have proved to be tolerable and therapeutically beneficial in animal studies, and a number are in clinical testing. The agents, their properties, and their molecular targets are discussed in this review.
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Affiliation(s)
- Nathan T Ihle
- M. D. Anderson Cancer Center, FC-6.3044, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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91
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Ihle NT, Lemos R, Schwartz D, Oh J, Halter RJ, Wipf P, Kirkpatrick L, Powis G. Peroxisome proliferator-activated receptor gamma agonist pioglitazone prevents the hyperglycemia caused by phosphatidylinositol 3-kinase pathway inhibition by PX-866 without affecting antitumor activity. Mol Cancer Ther 2009; 8:94-100. [PMID: 19139117 DOI: 10.1158/1535-7163.mct-08-0714] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The phosphatidylinositol 3-kinase (PI3K)/Akt signaling cascade is an important component of the insulin signaling in normal tissues leading to glucose uptake and homeostasis and for cell survival signaling in cancer cells. Hyperglycemia is an on-target side effect of many inhibitors of PI3K/Akt signaling including the specific PI3K inhibitor PX-866. The peroxisome proliferator-activated receptor gamma agonist pioglitazone, used to treat type 2 diabetes, prevents a decrease in glucose tolerance caused by acute administration of PX-866. Our studies have shown that pioglitazone does not inhibit the antitumor activity of PX-866 in A-549 non-small cell lung cancer and HT-29 colon cancer xenografts. In vitro studies also showed that pioglitazone increases 2-[1-(14)C]deoxy-D-glucose uptake in L-6 muscle cells and prevents inhibition of 2-deoxyglucose uptake by PX-866. Neither pioglitazone nor PX-866 had an effect on 2-deoxyglucose uptake in A-549 lung cancer cells. In vivo imaging studies using [18F]2-deoxyglucose (FDG) positron emission tomography showed that pioglitazone increases FDG accumulation by normal tissue but does not significantly alter FDG uptake by A-549 xenografts. Thus, peroxisome proliferator-activated receptor gamma agonists may be useful in overcoming the increase in blood glucose caused by inhibitors of PI3K signaling by preventing the inhibition of normal tissue insulin-mediated glucose uptake without affecting antitumor activity.
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Affiliation(s)
- Nathan T Ihle
- The University of Texas M. D. Anderson Cancer Center, FC-6.3044, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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92
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Abstract
In contrast with cytotoxic agents that do not differentiate between normal proliferating and tumour cells, targeted therapies primarily exert their actions in cancer cells. Initiation and maintenance of tumours are due to genetic alterations in specific loci. The identification of the genes in which these alterations occur has opened new opportunities for cancer treatment. The PI3K (phosphoinositide 3-kinase) pathway is often overactive in human cancers, and various genetic alterations have been found to cause this. In all cases, PI3K inhibition is considered to be one of the most promising targeted therapies for cancer treatment. The present mini-review provides an update on new PI3K inhibitors currently in or entering clinical development. Recent discoveries, challenges and future prospects will be discussed.
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93
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Ihle N, Lemos R, Wipf P, Yacoub A, Mitchell C, Siwak D, Mills GB, Dent P, Kirkpatrick DL, Powis G. Mutations in the phosphatidylinositol-3-kinase pathway predict for antitumor activity of the inhibitor PX-866 whereas oncogenic Ras is a dominant predictor for resistance. Cancer Res 2009; 69:143-50. [PMID: 19117997 PMCID: PMC2613546 DOI: 10.1158/0008-5472.can-07-6656] [Citation(s) in RCA: 235] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The novel phosphatidylinositol-3-kinase (PI3K) inhibitor PX-866 was tested against 13 experimental human tumor xenografts derived from cell lines of various tissue origins. Mutant PI3K (PIK3CA) and loss of PTEN activity were sufficient, but not necessary, as predictors of sensitivity to the antitumor activity of the PI3K inhibitor PX-866 in the presence of wild-type Ras, whereas mutant oncogenic Ras was a dominant determinant of resistance, even in tumors with coexisting mutations in PIK3CA. The level of activation of PI3K signaling measured by tumor phosphorylated Ser(473)-Akt was insufficient to predict in vivo antitumor response to PX-866. Reverse-phase protein array revealed that the Ras-dependent downstream targets c-Myc and cyclin B were elevated in cell lines resistant to PX-866 in vivo. Studies using an H-Ras construct to constitutively and preferentially activate the three best-defined downstream targets of Ras, i.e., Raf, RalGDS, and PI3K, showed that mutant Ras mediates resistance through its ability to use multiple pathways for tumorigenesis. The identification of Ras and downstream signaling pathways driving resistance to PI3K inhibition might serve as an important guide for patient selection as inhibitors enter clinical trials and for the development of rational combinations with other molecularly targeted agents.
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Affiliation(s)
- NathanT. Ihle
- MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, 77030, U.S.A
| | - Robert Lemos
- MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, 77030, U.S.A
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA,15260, U.S.A
| | - Adly Yacoub
- Virginia Commonwealth University School of Medicine, Richmond, VA, 23298,USA
| | - Clint Mitchell
- Virginia Commonwealth University School of Medicine, Richmond, VA, 23298,USA
| | - Doris Siwak
- MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, 77030, U.S.A
| | - Gordon B. Mills
- MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, 77030, U.S.A
| | - Paul Dent
- Virginia Commonwealth University School of Medicine, Richmond, VA, 23298,USA
| | | | - Garth Powis
- MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX, 77030, U.S.A
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94
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Abstract
Epidermal growth factor receptor (EGFR) inhibitors have introduced the concept of targeted therapy to the treatment of non-small cell lung cancer (NSCLC). These agents appear most effective in patients with tumors that are highly dependent on EGFR signaling pathways, a population that disproportionately includes females, nonsmokers, individuals of East Asian origin, and patients with adenocarcinoma histology. Currently available EGFR-inhibiting drugs include the tyrosine kinase inhibitors (TKIs) erlotinib, gefitinib, and lapatinib, which are administered orally and interfere with the intracellular tyrosine kinase domain, and the monoclonal antibodies (mAbs) cetuximab and panitumumab, which are administered intravenously and interfere with extracellular ligand binding. While the use of EGFR TKIs as monotherapy prolongs survival in metastatic NSCLC, they have demonstrated no benefit when added to conventional, cytotoxic chemotherapy. In contrast, the anti-EGFR mAb cetuximab appears most effective when combined with chemotherapy or radiation. Despite dramatic initial responses to treatment in some cases, NSCLC eventually becomes resistant to EGFR inhibition. Possible mechanisms include secondary mutations that interfere with drug binding, oncogenic pathways driven by other receptor tyrosine kinases, and independent activity of downstream signaling molecules. Efforts to overcome such resistance include irreversibly binding EGFR TKIs, multi-targeted TKIs, and combinations with chemotherapy, radiation, and other targeted therapies.
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Affiliation(s)
- David E. Gerber
- Department of Internal Medicine, Division of Hematology-Oncology, University of Texas Southwestern Medical Center, Dallas, TX 75390-8852
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95
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Garcia-Echeverria C, Sellers WR. Drug discovery approaches targeting the PI3K/Akt pathway in cancer. Oncogene 2008; 27:5511-26. [PMID: 18794885 DOI: 10.1038/onc.2008.246] [Citation(s) in RCA: 355] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The abnormal activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway has been validated by epidemiological and experimental studies as an essential step toward the initiation and maintenance of human tumors. Notable in this regard are the prevalent somatic genetic alterations leading to the inactivation of the tumor suppressor gene PTEN and gain-of-function mutations targeting PIK3CA--the gene encoding the catalytic phosphosinositide-3 kinase subunit p110 alpha. A number of the intracellular components of this pathway have been targeted as anticancer drug discovery activities leading to the current panoply of clinical trials of inhibitors of PI3K, Akt and HSP90 in man. This review summarizes current preclinical knowledge of modulators of the PI3K/Akt pathway in which drug discovery and development activities have been advanced focusing on both the relevant clinical stage inhibitors and other disclosed tool compounds targeting PI3K, PDK1, Akt and HSP90.
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Affiliation(s)
- C Garcia-Echeverria
- Oncology Drug Discovery, Novartis Institutes for Biomedical Research, Basel, Switzerland.
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96
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Kong D, Yamori T. Phosphatidylinositol 3-kinase inhibitors: promising drug candidates for cancer therapy. Cancer Sci 2008; 99:1734-40. [PMID: 18616528 PMCID: PMC11160043 DOI: 10.1111/j.1349-7006.2008.00891.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Phosphatidylinositol 3-kinases (PI3K) are a group of lipid kinases that phosphorylate phosphoinositides at the 3-hydroxyl group of the inositol ring to generate phosphatidylinositol 3,4,5-trisphosphate, a second messenger with key roles in fundamental cellular responses such as cell proliferation and metabolism. Frequent mutations found in or amplification of the PIK3CA gene and loss of phosphatase and tensin homolog deleted on chromosome 10 function in human tumors suggest that PI3K is a potential target for cancer therapy. During the last 5 years, several specific PI3K inhibitors were developed that were directed against various diseases. Some of them revealed potent anticancer efficacy and are now undergoing clinical trials. Some PI3K inhibitors showed antiangiogenic effects. Combined use of PI3K inhibitors with other chemotherapeutic agents or with radiotherapy produced synergistic therapeutic efficacies in treating cancer and showed reduced side effects. The rapid progress made in developing novel PI3K inhibitors in recent years promises bright prospects for finding a PI3K-targeted anticancer drug in the near future.
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Affiliation(s)
- Dexin Kong
- Division of Molecular Pharmacology, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo 135-8550, Japan
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97
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Protein and lipid kinase inhibitors as targeted anticancer agents of the Ras/Raf/MEK and PI3K/PKB pathways. Purinergic Signal 2008; 5:117-25. [PMID: 18523868 PMCID: PMC2721773 DOI: 10.1007/s11302-008-9111-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2008] [Accepted: 04/28/2008] [Indexed: 11/03/2022] Open
Abstract
The identification and characterization of the components of individual signal transduction cascades, and advances in our understanding on how these biological signals are integrated in cancer initiation and progression, have provided new strategies for therapeutic intervention in solid tumors and hematological malignancies. To this end, pharmaceutical efforts have been directed to target different components of the Ras/Raf/MEK and PI3K/PKB pathways. This review article covers recent salient achievements in the identification and development of Raf, MEK, and PI3K inhibitors.
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98
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Sithanandam G, Anderson LM. The ERBB3 receptor in cancer and cancer gene therapy. Cancer Gene Ther 2008; 15:413-48. [PMID: 18404164 DOI: 10.1038/cgt.2008.15] [Citation(s) in RCA: 180] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
ERBB3, a member of the epidermal growth factor receptor (EGFR) family, is unique in that its tyrosine kinase domain is functionally defective. It is activated by neuregulins, by other ERBB and nonERBB receptors as well as by other kinases, and by novel mechanisms. Downstream it interacts prominently with the phosphoinositol 3-kinase/AKT survival/mitogenic pathway, but also with GRB, SHC, SRC, ABL, rasGAP, SYK and the transcription regulator EBP1. There are likely important but poorly understood roles for nuclear localization and for secreted isoforms. Studies of ERBB3 expression in primary cancers and of its mechanistic contributions in cultured cells have implicated it, with varying degrees of certainty, with causation or sustenance of cancers of the breast, ovary, prostate, certain brain cells, retina, melanocytes, colon, pancreas, stomach, oral cavity and lung. Recent results link high ERBB3 activity with escape from therapy targeting other ERBBs in lung and breast cancers. Thus a wide and centrally important role for ERBB3 in cancer is becoming increasingly apparent. Several approaches for targeting ERBB3 in cancers have been tested or proposed. Small inhibitory RNA (siRNA) to ERBB3 or AKT is showing promise as a therapeutic approach to treatment of lung adenocarcinoma.
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99
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LoPiccolo J, Blumenthal GM, Bernstein WB, Dennis PA. Targeting the PI3K/Akt/mTOR pathway: effective combinations and clinical considerations. Drug Resist Updat 2008; 11:32-50. [PMID: 18166498 PMCID: PMC2442829 DOI: 10.1016/j.drup.2007.11.003] [Citation(s) in RCA: 601] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 11/19/2007] [Accepted: 11/19/2007] [Indexed: 12/15/2022]
Abstract
The PI3K/Akt/mTOR pathway is a prototypic survival pathway that is constitutively activated in many types of cancer. Mechanisms for pathway activation include loss of tumor suppressor PTEN function, amplification or mutation of PI3K, amplification or mutation of Akt, activation of growth factor receptors, and exposure to carcinogens. Once activated, signaling through Akt can be propagated to a diverse array of substrates, including mTOR, a key regulator of protein translation. This pathway is an attractive therapeutic target in cancer because it serves as a convergence point for many growth stimuli, and through its downstream substrates, controls cellular processes that contribute to the initiation and maintenance of cancer. Moreover, activation of the Akt/mTOR pathway confers resistance to many types of cancer therapy, and is a poor prognostic factor for many types of cancers. This review will provide an update on the clinical progress of various agents that target the pathway, such as the Akt inhibitors perifosine and PX-866 and mTOR inhibitors (rapamycin, CCI-779, RAD-001) and discuss strategies to combine these pathway inhibitors with conventional chemotherapy, radiotherapy, as well as newer targeted agents. We will also discuss how the complex regulation of the PI3K/Akt/mTOR pathway poses practical issues concerning the design of clinical trials, potential toxicities and criteria for patient selection.
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Affiliation(s)
- Jaclyn LoPiccolo
- Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20889
| | - Gideon M. Blumenthal
- Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20889
| | - Wendy B. Bernstein
- Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20889
| | - Phillip A. Dennis
- Medical Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20889
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100
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Maira SM, Voliva C, Garcia-Echeverria C. Class IA phosphatidylinositol 3-kinase: from their biologic implication in human cancers to drug discovery. Expert Opin Ther Targets 2008; 12:223-38. [DOI: 10.1517/14728222.12.2.223] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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