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Jiang Y, Yuan Y, Qiao G, Deng Z, Liu Z, Zhang Y, Yu L, Lin H, Ma L, Zhang J. Paradoxical action of PP2A inhibition and its potential for therapeutic sensitization. J Cell Physiol 2024:e31413. [PMID: 39150149 DOI: 10.1002/jcp.31413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 07/19/2024] [Accepted: 08/07/2024] [Indexed: 08/17/2024]
Abstract
The protein phosphatase 2A (PP2A), a serine/threonine phosphatase, is recognized as a tumor suppressor involved in diverse cellular processes and essential for maintaining cell viability in vivo. However, endogenous inhibitors of PP2A such as cancerous inhibitor of PP2A (CIP2A) and endogenous nuclear protein inhibitor 2 of PP2A (SET) counteract the anticancer function of PP2A, promoting tumorigenesis, development, and drug resistance in tumors. Surprisingly though, contrary to conventional understanding, inhibition of the tumor suppressor gene PP2A with exogenous small molecule compounds can enhance the efficacy of cancer treatment and achieve superior tumor inhibition. Moreover, exogenous PP2A inhibitors resensitize cancers to treatment and provide novel therapeutic strategies for drug-resistant tumors, which warrant further investigation.
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Affiliation(s)
- Yue Jiang
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ying Yuan
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Guanglei Qiao
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Zhoufeng Deng
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Zimei Liu
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yan Zhang
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Liping Yu
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Hongjian Lin
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Lijun Ma
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jianjun Zhang
- Department of Oncology, Shanghai Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
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Chiou JT, Wu YY, Lee YC, Chang LS. BCL2L1 inhibitor A-1331852 inhibits MCL1 transcription and triggers apoptosis in acute myeloid leukemia cells. Biochem Pharmacol 2023; 215:115738. [PMID: 37562509 DOI: 10.1016/j.bcp.2023.115738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 08/04/2023] [Accepted: 08/07/2023] [Indexed: 08/12/2023]
Abstract
BH3 mimetics exert anticancer activity by inhibiting anti-apoptotic BCL2 proteins. However, accumulating evidence indicates that the off-target effects of these drugs tightly modulates their anticancer activities. In this study, we investigated whether the BCL2L1 inhibitor A-1331852 induced the death of U937 acute myeloid leukemia (AML) cells through a non-BCL2L1-targeted effect. A-1331852-induced apoptosis in U937 cells was characterized by increased ROS production, downregulation of MCL1, and loss of mitochondrial membrane potential. Ectopic expression of MCL1 alleviated A-1331852-induced mitochondrial depolarization and cytotoxicity in U937 cells. A-1331852-induced ROS production increased p38 MAPK phosphorylation and inhibited MCL1 transcription. Inhibition of p38 MAPK activation restored MCL1 expression in A-1331852-treated cells. A-1331852 triggered p38 MAPK-mediated Cullin 3 downregulation, which in turn increased PP2Acα expression, thereby reducing CREB phosphorylation. A-1331852 reduced the binding of CREB to the MCL1 promoter, leading to the inhibition of CREB-mediated MCL1 transcription. Furthermore, A-1331852 acted synergistically with the BCL2 inhibitor ABT-199 to induce U937 and ABT-199-resistant U937 cell death by inhibiting MCL1 expression. A similar phenomenon caused A-1331852-induced MCL1 downregulation and cytotoxicity in AML HL-60 cells. Collectively, our data suggest that A-1331852 shows an off-target effect of inhibiting MCL1 transcription, ultimately leading to U937 and HL-60 cell death.
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Affiliation(s)
- Jing-Ting Chiou
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Yu-Ying Wu
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Yuan-Chin Lee
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Long-Sen Chang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan; Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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3
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Ursolic Acid Ameliorates Myocardial Ischaemia/Reperfusion Injury by Improving Mitochondrial Function via Immunoproteasome-PP2A-AMPK Signalling. Nutrients 2023; 15:nu15041049. [PMID: 36839407 PMCID: PMC9967761 DOI: 10.3390/nu15041049] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 02/16/2023] [Accepted: 02/18/2023] [Indexed: 02/22/2023] Open
Abstract
Cardiac ischaemia/reperfusion (I/R) injury causes cardiomyocyte apoptosis and mitochondrial dysfunction. Ursolic acid (UA), as a pentacyclic triterpenoid carboxylic acid, exerts several bioactivities in animal models of different diseases, but the preventive role of UA in I/R-induced myocardial dysfunction remains largely unknown. Male wild-type mice were pre-administered with UA at a dosage of 80 mg/kg i.p. and then subjected to cardiac I/R injury for 24 h. Cardiac function and pathological changes were examined by echocardiography and histological staining. The protein and mRNA levels of the genes were determined using qPCR and immunoblotting analysis. Our results revealed that UA administration in mice significantly attenuated the I/R-induced decline in cardiac function, infarct size, myocyte apoptosis, and oxidative stress. Mechanistically, UA increased three immunoproteasome catalytic subunit expressions and activities, which promoted ubiquitinated PP2A degradation and activated AMPK-PGC1α signalling, leading to improved mitochondrial biosynthesis and dynamic balance. In vitro experiments confirmed that UA treatment prevented hypoxia/reperfusion (H/R)-induced cardiomyocyte apoptosis and mitochondrial dysfunction through activation of AMPK signalling. In summary, our findings identify UA as a new activator of the immunoproteasome that exerts a protective role in I/R-induced myocardial dysfunction and suggest that UA supplementation could be beneficial for the prevention of cardiac ischaemic disease.
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Pimentel JM, Zhou JY, Wu GS. Regulation of programmed death ligand 1 (PD-L1) expression by TNF-related apoptosis-inducing ligand (TRAIL) in triple-negative breast cancer cells. Mol Carcinog 2023; 62:135-144. [PMID: 36239572 PMCID: PMC10015553 DOI: 10.1002/mc.23471] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/27/2022] [Accepted: 09/28/2022] [Indexed: 01/21/2023]
Abstract
Triple-negative breast cancer (TNBC) is an aggressive form of breast cancer that lacks targeted therapies. Previous studies have shown that TNBC cells are highly sensitive to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), making it a promising agent for treating TNBC. However, the development of TRAIL resistance limits its further clinical development, and the underlying mechanisms are not fully understood. In this study, we report the role of PD-L1 in TRAIL resistance. Specifically, we found that TRAIL treatment increases PD-L1 expression in TRAIL-sensitive cells and that basal PD-L1 expression is increased in acquired TRAIL-resistant cells. Mechanistically, we found that increased PD-L1 expression was accompanied by increased extracellular signal-regulated kinase (ERK) activation. Using both genetic and pharmacological approaches, we showed that knockdown of ERK by siRNA or inhibition of ERK activation by the mitogen-activated protein kinase kinase inhibitor U0126 decreased PD-L1 expression and increased TRAIL-induced cell death. Furthermore, we found that knockout or knockdown of PD-L1 enhances TRAIL-induced apoptosis, suggesting that PD-L1-mediated TRAIL resistance is independent of its ability to evade immune suppression. Therefore, this study identifies a noncanonical mechanism by which PD-L1 promotes TRAIL resistance, which can be potentially exploited for immune checkpoint therapy.
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Affiliation(s)
- Julio M. Pimentel
- Molecular Therapeutics Program, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan 48201
- Cancer Biology Program, Wayne State University School of Medicine, Detroit, Michigan 48201
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Jun-Ying Zhou
- Molecular Therapeutics Program, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan 48201
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Gen Sheng Wu
- Molecular Therapeutics Program, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan 48201
- Cancer Biology Program, Wayne State University School of Medicine, Detroit, Michigan 48201
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan 48201
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5
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Wu J, Fang S, Lu KT, Kumar G, Reho JJ, Brozoski DT, Otanwa AJ, Hu C, Nair AR, Wackman KK, Agbor LN, Grobe JL, Sigmund CD. Endothelial Cullin3 Mutation Impairs Nitric Oxide-Mediated Vasodilation and Promotes Salt-Induced Hypertension. FUNCTION (OXFORD, ENGLAND) 2022; 3:zqac017. [PMID: 35493997 PMCID: PMC9045850 DOI: 10.1093/function/zqac017] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 01/13/2023]
Abstract
Human hypertension caused by in-frame deletion of CULLIN3 exon-9 (Cul3∆9) is driven by renal and vascular mechanisms. We bred conditionally activatable Cul3∆9 transgenic mice with tamoxifen-inducible Tie2-CREERT2 mice to test the importance of endothelial Cul3. The resultant mice (E-Cul3∆9) trended towards elevated nighttime blood pressure (BP) correlated with increased nighttime activity, but displayed no difference in daytime BP or activity. Male and female E-Cul3∆9 mice together exhibited a decline in endothelial-dependent relaxation in carotid artery. Male but not female E-Cul3∆9 mice displayed severe endothelial dysfunction in cerebral basilar artery. There was no impairment in mesenteric artery and no difference in smooth muscle function, suggesting the effects of Cul3∆9 are arterial bed-specific and sex-dependent. Expression of Cul3∆9 in primary mouse aortic endothelial cells decreased endogenous Cul3 protein, phosphorylated (S1177) endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) production. Protein phosphatase (PP) 2A, a known Cul3 substrate, dephosphorylates eNOS. Cul3∆9-induced impairment of eNOS activity was rescued by a selective PP2A inhibitor okadaic acid, but not by a PP1 inhibitor tautomycetin. Because NO deficiency contributes to salt-induced hypertension, we tested the salt-sensitivity of E-Cul3∆9 mice. While both male and female E-Cul3∆9 mice developed salt-induced hypertension and renal injury, the pressor effect of salt was greater in female mutants. The increased salt-sensitivity in female E-Cul3∆9 mice was associated with decreased renovascular relaxation and impaired natriuresis in response to a sodium load. Thus, CUL3 mutations in the endothelium may contribute to human hypertension in part through decreased endothelial NO bioavailability, renovascular dysfunction, and increased salt-sensitivity of BP.
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Affiliation(s)
- Jing Wu
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
| | - Shi Fang
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA,Department of Neuroscience and Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, 52242 Iowa, USA
| | - Ko-Ting Lu
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
| | - Gaurav Kumar
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
| | - John J Reho
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
| | - Daniel T Brozoski
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
| | - Adokole J Otanwa
- Department of Neuroscience and Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, 52242 Iowa, USA
| | - Chunyan Hu
- Department of Neuroscience and Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, 52242 Iowa, USA
| | - Anand R Nair
- Department of Neuroscience and Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, 52242 Iowa, USA
| | - Kelsey K Wackman
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
| | - Larry N Agbor
- Department of Neuroscience and Pharmacology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, 52242 Iowa, USA
| | - Justin L Grobe
- Deparment of Physiology, Cardiovascular Center, Medical College of Wisconsin, Milwaukee, 53226 Wisconsin, USA
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Potassium Effects on NCC Are Attenuated during Inhibition of Cullin E3-Ubiquitin Ligases. Cells 2021; 11:cells11010095. [PMID: 35011657 PMCID: PMC8750104 DOI: 10.3390/cells11010095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/20/2021] [Accepted: 12/22/2021] [Indexed: 01/02/2023] Open
Abstract
The thiazide-sensitive sodium chloride cotransporter (NCC) plays a vital role in maintaining sodium (Na+) and potassium (K+) homeostasis. NCC activity is modulated by with-no-lysine kinases 1 and 4 (WNK1 and WNK4), the abundance of which is controlled by the RING-type E3 ligase Cullin 3 (Cul3) and its substrate adapter Kelch-like protein 3. Dietary K+ intake has an inverse correlation with NCC activity, but the mechanism underlying this phenomenon remains to be fully elucidated. Here, we investigated the involvement of other members of the cullin family in mediating K+ effects on NCC phosphorylation (active form) and abundance. In kidneys from mice fed diets varying in K+ content, there were negative correlations between NCC (phosphorylated and total) and active (neddylated) forms of cullins (Cul1, 3, 4, and 5). High dietary K+ effects on phosphorylated NCC were attenuated in Cul3 mutant mice (CUL3-Het/Δ9). Short-term (30 min) and long-term (24 h) alterations in the extracellular K+ concentration did not affect cullin neddylation levels in ex vivo renal tubules. In the short term, the ability of high extracellular K+ to decrease NCC phosphorylation was preserved in the presence of MLN4924 (pan-cullin inhibitor), but the response to low extracellular K+ was absent. In the long term, MLN4924 attenuated the effects of high extracellular K+ on NCC phosphorylation, and responses to low extracellular K+ were absent. Our data suggest that in addition to Cul3, other cullins are involved in mediating the effects of K+ on NCC phosphorylation and abundance.
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Uddin MH, Pimentel JM, Chatterjee M, Allen JE, Zhuang Z, Wu GS. Targeting PP2A inhibits the growth of triple-negative breast cancer cells. Cell Cycle 2020; 19:592-600. [PMID: 32011210 DOI: 10.1080/15384101.2020.1723195] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Triple-negative breast cancer (TNBC) does not respond to widely used targeted/endocrine therapies because of the absence of progesterone and estrogen receptors and HER2 amplification. It has been shown that the majority of TNBC cells are highly sensitive to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis, but the development of TRAIL resistance limits its efficacy. We previously found that protein phosphatase 2A (PP2A) plays an important role in TRAIL resistance. In this study, we evaluated the effects of PP2A inhibition on cell death in TRAIL-resistant TNBC cells. We found that the PP2A inhibitor LB-100 effectively inhibits the growth of a panel of TNBC cell lines including lines that are intrinsically resistant to TRAIL. Using two TRAIL-resistant cell lines generated from TRAIL-sensitive parental cells (MDA231 and SUM159), we found that both TRAIL-sensitive and -resistant cell lines are equally sensitive to LB-100. We also found that LB-100 sensitizes TNBC cells to clinically used chemotherapeutical agents, including paclitaxel and cisplatin. Importantly, we found that LB-100 effectively inhibits the growth of MDA468 tumors in mice in vivo without apparent toxicity. Collectively, these data suggest that pharmacological inhibition of PP2A activity could be a novel therapeutic strategy for treating patients with TNBC in a clinical setting.
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Affiliation(s)
- Mohammed Hafiz Uddin
- Department of Oncology and Pathology, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Julio M Pimentel
- Department of Oncology and Pathology, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA.,Cancer Biology Program, Wayne State University School of Medicine, Detroit, MI, USA
| | - Madhumita Chatterjee
- Department of Oncology and Pathology, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA
| | - Joshu E Allen
- Department of Research and Development, Oncoceutics, Inc, Philadelphia, PA, USA
| | - Zhengping Zhuang
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Gen Sheng Wu
- Department of Oncology and Pathology, Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI, USA.,Cancer Biology Program, Wayne State University School of Medicine, Detroit, MI, USA
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Arman T, Lynch KD, Montonye ML, Goedken M, Clarke JD. Sub-Chronic Microcystin-LR Liver Toxicity in Preexisting Diet-Induced Nonalcoholic Steatohepatitis in Rats. Toxins (Basel) 2019; 11:E398. [PMID: 31323923 PMCID: PMC6669744 DOI: 10.3390/toxins11070398] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/02/2019] [Accepted: 07/04/2019] [Indexed: 02/07/2023] Open
Abstract
Microcystin-LR (MCLR) is a hepatotoxic cyanotoxin reported to cause a phenotype similar to nonalcoholic steatohepatitis (NASH). NASH is a common progressive liver disease that advances in severity due to exogenous stressors such as poor diet and toxicant exposure. Our objective was to determine how sub-chronic MCLR toxicity affects preexisting diet-induced NASH. Sprague-Dawley rats were fed one of three diets for 10 weeks: control, methionine and choline deficient (MCD), or high fat/high cholesterol (HFHC). After six weeks of diet, animals received vehicle, 10 µg/kg, or 30 µg/kg MCLR via intraperitoneal injection every other day for the final 4 weeks. Incidence and severity scoring of histopathology endpoints suggested that MCLR toxicity drove NASH to a less fatty and more fibrotic state. In general, expression of genes involved in de novo lipogenesis and fatty acid esterification were altered in favor of decreased steatosis. The higher MCLR dose increased expression of genes involved in fibrosis and inflammation in the control and HFHC groups. These data suggest MCLR toxicity in the context of preexisting NASH may drive the liver to a more severe phenotype that resembles burnt-out NASH.
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Affiliation(s)
- Tarana Arman
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Katherine D Lynch
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Michelle L Montonye
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA
| | - Michael Goedken
- Department of Pharmacology and Toxicology, Rutgers University, Piscataway, NJ 08901, USA
| | - John D Clarke
- Department of Pharmaceutical Sciences, Washington State University, Spokane, WA 99202, USA.
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Brautigan DL, Shenolikar S. Protein Serine/Threonine Phosphatases: Keys to Unlocking Regulators and Substrates. Annu Rev Biochem 2019; 87:921-964. [PMID: 29925267 DOI: 10.1146/annurev-biochem-062917-012332] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Protein serine/threonine phosphatases (PPPs) are ancient enzymes, with distinct types conserved across eukaryotic evolution. PPPs are segregated into types primarily on the basis of the unique interactions of PPP catalytic subunits with regulatory proteins. The resulting holoenzymes dock substrates distal to the active site to enhance specificity. This review focuses on the subunit and substrate interactions for PPP that depend on short linear motifs. Insights about these motifs from structures of holoenzymes open new opportunities for computational biology approaches to elucidate PPP networks. There is an expanding knowledge base of posttranslational modifications of PPP catalytic and regulatory subunits, as well as of their substrates, including phosphorylation, acetylation, and ubiquitination. Cross talk between these posttranslational modifications creates PPP-based signaling. Knowledge of PPP complexes, signaling clusters, as well as how PPPs communicate with each other in response to cellular signals should unlock the doors to PPP networks and signaling "clouds" that orchestrate and coordinate different aspects of cell physiology.
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Affiliation(s)
- David L Brautigan
- Center for Cell Signaling and Department of Microbiology, Immunology and Cancer Biology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA;
| | - Shirish Shenolikar
- Signature Research Programs in Cardiovascular and Metabolic Disorders and Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore 169857
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Abstract
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF superfamily that can initiate the apoptosis pathway by binding to its associated death receptors DR4 and DR5. The activation of the TRAIL pathway in inducing tumor-selective apoptosis leads to the development of TRAIL-based cancer therapies, which include recombinant forms of TRAIL, TRAIL receptor agonists, and other therapeutic agents. Importantly, TRAIL, DR4, and DR5 can all be induced by synthetic and natural agents that activate the TRAIL apoptosis pathway in cancer cells. Thus, understanding the regulation of the TRAIL apoptosis pathway can aid in the development of TRAIL-based therapies for the treatment of human cancer.
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11
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Jang SM, Redon CE, Aladjem MI. Chromatin-Bound Cullin-Ring Ligases: Regulatory Roles in DNA Replication and Potential Targeting for Cancer Therapy. Front Mol Biosci 2018; 5:19. [PMID: 29594129 PMCID: PMC5859106 DOI: 10.3389/fmolb.2018.00019] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 02/12/2018] [Indexed: 12/14/2022] Open
Abstract
Cullin-RING (Really Interesting New Gene) E3 ubiquitin ligases (CRLs), the largest family of E3 ubiquitin ligases, are functional multi-subunit complexes including substrate receptors, adaptors, cullin scaffolds, and RING-box proteins. CRLs are responsible for ubiquitination of ~20% of cellular proteins and are involved in diverse biological processes including cell cycle progression, genome stability, and oncogenesis. Not surprisingly, cullins are deregulated in many diseases and instances of cancer. Recent studies have highlighted the importance of CRL-mediated ubiquitination in the regulation of DNA replication/repair, including specific roles in chromatin assembly and disassembly of the replication machinery. The development of novel therapeutics targeting the CRLs that regulate the replication machinery and chromatin in cancer is now an attractive therapeutic strategy. In this review, we summarize the structure and assembly of CRLs and outline their cellular functions and their diverse roles in cancer, emphasizing the regulatory functions of nuclear CRLs in modulating the DNA replication machinery. Finally, we discuss the current strategies for targeting CRLs against cancer in the clinic.
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Affiliation(s)
| | | | - Mirit I. Aladjem
- Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, United States
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12
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Nair PM, Starkey MR, Haw TJ, Liu G, Horvat JC, Morris JC, Verrills NM, Clark AR, Ammit AJ, Hansbro PM. Targeting PP2A and proteasome activity ameliorates features of allergic airway disease in mice. Allergy 2017; 72:1891-1903. [PMID: 28543283 DOI: 10.1111/all.13212] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/20/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Asthma is an allergic airway disease (AAD) caused by aberrant immune responses to allergens. Protein phosphatase-2A (PP2A) is an abundant serine/threonine phosphatase with anti-inflammatory activity. The ubiquitin proteasome system (UPS) controls many cellular processes, including the initiation of inflammatory responses by protein degradation. We assessed whether enhancing PP2A activity with fingolimod (FTY720) or 2-amino-4-(4-(heptyloxy) phenyl)-2-methylbutan-1-ol (AAL(S) ), or inhibiting proteasome activity with bortezomib (BORT), could suppress experimental AAD. METHODS Acute AAD was induced in C57BL/6 mice by intraperitoneal sensitization with ovalbumin (OVA) in combination with intranasal (i.n) exposure to OVA. Chronic AAD was induced in mice with prolonged i.n exposure to crude house dust mite (HDM) extract. Mice were treated with vehicle, FTY720, AAL(S) , BORT or AAL(S) +BORT and hallmark features of AAD assessed. RESULTS AAL(S) reduced the severity of acute AAD by suppressing tissue eosinophils and inflammation, mucus-secreting cell (MSC) numbers, type 2-associated cytokines (interleukin (IL)-33, thymic stromal lymphopoietin, IL-5 and IL-13), serum immunoglobulin (Ig)E and airway hyper-responsiveness (AHR). FTY720 only suppressed tissue inflammation and IgE. BORT reduced bronchoalveolar lavage fluid (BALF) and tissue eosinophils and inflammation, IL-5, IL-13 and AHR. Combined treatment with AAL(S) +BORT had complementary effects and suppressed BALF and tissue eosinophils and inflammation, MSC numbers, reduced the production of type 2 cytokines and AHR. AAL(S) , BORT and AAL(S) +BORT also reduced airway remodelling in chronic AAD. CONCLUSION These findings highlight the potential of combination therapies that enhance PP2A and inhibit proteasome activity as novel therapeutic strategies for asthma.
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Affiliation(s)
- P. M. Nair
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
| | - M. R. Starkey
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
| | - T. J. Haw
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
| | - G. Liu
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
| | - J. C. Horvat
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
| | - J. C. Morris
- School of Chemistry; University of New South Wales; Sydney NSW Australia
| | - N. M. Verrills
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
| | - A. R. Clark
- Institute of Inflammation and Ageing; College of Medical and Dental Sciences; University of Birmingham; Birmingham UK
| | - A. J. Ammit
- Woolcock Emphysema Centre; Woolcock Institute of Medical Research; University of Sydney; Sydney NSW Australia
- Faculty of Science; School of Life Sciences; University of Technology Sydney; Sydney NSW Australia
| | - P. M. Hansbro
- Priority Research Centres for Healthy Lungs; Grow up Well and Cancer Research, Innovation and Translation; University of Newcastle & Hunter Medical Research Institute; New Lambton Heights NSW Australia
- Faculty of Health and Medicine; School of Biomedical Sciences and Pharmacy; University of Newcastle; Callaghan NSW Australia
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13
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Zhao M, Howard EW, Parris AB, Guo Z, Zhao Q, Ma Z, Xing Y, Liu B, Edgerton SM, Thor AD, Yang X. Activation of cancerous inhibitor of PP2A (CIP2A) contributes to lapatinib resistance through induction of CIP2A-Akt feedback loop in ErbB2-positive breast cancer cells. Oncotarget 2017; 8:58847-58864. [PMID: 28938602 PMCID: PMC5601698 DOI: 10.18632/oncotarget.19375] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 07/11/2017] [Indexed: 11/25/2022] Open
Abstract
Lapatinib, a small molecule ErbB2/EGFR inhibitor, is FDA-approved for the treatment of metastatic ErbB2-overexpressing breast cancer; however, lapatinib resistance is an emerging clinical challenge. Understanding the molecular mechanisms of lapatinib-mediated anti-cancer activities and identifying relevant resistance factors are of pivotal significance. Cancerous inhibitor of protein phosphatase 2A (CIP2A) is a recently identified oncoprotein that is overexpressed in breast cancer. Our study investigated the role of CIP2A in the anti-cancer efficacy of lapatinib in ErbB2-overexpressing breast cancer cells. We found that lapatinib concurrently downregulated CIP2A and receptor tyrosine kinase signaling in ErbB2-overexpressing SKBR3 and 78617 cells; however, these effects were attenuated in lapatinib-resistant (LR) cells. CIP2A overexpression rendered SKBR3 and 78617 cells resistant to lapatinib-induced apoptosis and growth inhibition. Conversely, CIP2A knockdown via lentiviral shRNA enhanced cell sensitivity to lapatinib-induced growth inhibition and apoptosis. Results also suggested that lapatinib downregulated CIP2A through regulation of protein stability. We further demonstrated that lapatinib-induced CIP2A downregulation can be recapitulated by LY294002, suggesting that Akt mediates CIP2A upregulation. Importantly, lapatinib induced differential CIP2A downregulation between parental BT474 and BT474/LR cell lines. Moreover, CIP2A shRNA knockdown significantly sensitized the BT474/LR cells to lapatinib. Collectively, our results demonstrate that CIP2A is a molecular target and resistance factor of lapatinib with a critical role in lapatinib-induced cellular responses, including the inhibition of the CIP2A-Akt feedback loop. Further investigation of lapatinib-mediated CIP2A regulation will advance our understanding of lapatinib-associated anti-tumor activities and drug resistance.
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Affiliation(s)
- Ming Zhao
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA
| | - Erin W Howard
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA
| | - Amanda B Parris
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA
| | - Zhiying Guo
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA
| | - Qingxia Zhao
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA.,Basic Medical College of Zhengzhou University, Zhengzhou, Henan, P.R. China
| | - Zhikun Ma
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA
| | - Ying Xing
- Basic Medical College of Zhengzhou University, Zhengzhou, Henan, P.R. China
| | - Bolin Liu
- Department of Pathology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Susan M Edgerton
- Department of Pathology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Ann D Thor
- Department of Pathology, School of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Xiaohe Yang
- Julius L. Chambers Biomedical/Biotechnology Research Institute and Department of Biological and Biomedical Sciences, North Carolina Central University, Kannapolis, North Carolina, USA.,College of Medicine, Henan University of Sciences and Technology, Luoyang, Henan, P.R. China
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14
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Farooqi AA, Gadaleta CD, Ranieri G, Fayyaz S, Marech I. New Frontiers in Promoting TRAIL-Mediated Cell Death: Focus on Natural Sensitizers, miRNAs, and Nanotechnological Advancements. Cell Biochem Biophys 2016; 74:3-10. [PMID: 26972296 DOI: 10.1007/s12013-015-0712-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cancer is a multifaceted and genomically complex disease, and rapidly emerging scientific evidence is emphasizing on intra-tumor heterogeneity within subpopulations of tumor cells and rapidly developing resistance against different molecular therapeutics. There is an overwhelmingly increasing list of agents currently being tested for efficacy against cancer. In accordance with the concept that therapeutic agents must have fewer off target effects and considerable efficacy, TRAIL has emerged as one among the most deeply investigated proteins reportedly involved in differential killing of tumor cells. Considerable killing activity of TRAIL against different cancers advocated its entry into clinical trials. However, data obtained through preclinical and cell culture studies are deepening our understanding of wide-ranging mechanisms which induce resistance against TRAIL-based therapeutics. These include downregulation of death receptors, overexpression of oncogenes, inactivation of tumor suppressor genes, imbalance of pro- and anti-apoptotic proteins, and inactivation of intrinsic and extrinsic pathways. Substantial fraction of information has been added into existing pool of knowledge related to TRAIL biology and recently accumulating evidence is adding new layers to regulation of TRAIL-induced apoptosis. Certain hints have emerged underscoring miR135a-3p- and miR-143-mediated regulation of TRAIL-induced apoptosis, and natural agents have shown remarkable efficacy in improving TRAIL-based therapeutics by increasing expression of tumor suppressor miRNAs. In this review, we summarize most recent breakthroughs related to naturopathy and strategies to nanotechnologically deliver TRAIL to the target site in xenografted mice. We also set spotlight on positive and negative regulators of TRAIL-mediated signaling. Comprehensive knowledge of genetics and proteomics of TRAIL-based signaling network obtained from cancer patients of different populations will be helpful in getting a step closer to personalized medicine.
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Affiliation(s)
- Ammad Ahmad Farooqi
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan.
| | - Cosmo Damiano Gadaleta
- Interventional Radiology Unit with Integrated Section of Translational Medical Oncology, National Cancer Research Centre Istituto Tumori "Giovanni Paolo II", Bari, Italy
| | - Girolamo Ranieri
- Interventional Radiology Unit with Integrated Section of Translational Medical Oncology, National Cancer Research Centre Istituto Tumori "Giovanni Paolo II", Bari, Italy
| | - Sundas Fayyaz
- Laboratory for Translational Oncology and Personalized Medicine, Rashid Latif Medical College, Lahore, Pakistan
| | - Ilaria Marech
- Interventional Radiology Unit with Integrated Section of Translational Medical Oncology, National Cancer Research Centre Istituto Tumori "Giovanni Paolo II", Bari, Italy
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15
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Yang CC, Kuai XX, Gao WB, Yu JC, Wang Q, Li L, Zhang L. Morroniside-Induced PP2A Activation Antagonizes Tau Hyperphosphorylation in a Cellular Model of Neurodegeneration. J Alzheimers Dis 2016; 51:33-44. [PMID: 26836014 DOI: 10.3233/jad-150728] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Cui-cui Yang
- Department of Pharmacology, Xuanwu Hospital of Capital Medical University; Beijing Institute for Brain disorder; Beijing Engineering Research Center for Nerve System Drugs; Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
| | - Xue-xian Kuai
- Department of Pharmacology, Xuanwu Hospital of Capital Medical University; Beijing Institute for Brain disorder; Beijing Engineering Research Center for Nerve System Drugs; Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Wen-bin Gao
- Department of Pharmacology, Xuanwu Hospital of Capital Medical University; Beijing Institute for Brain disorder; Beijing Engineering Research Center for Nerve System Drugs; Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Jian-chun Yu
- First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Qi Wang
- Institute of Clinical Pharmacology, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Lin Li
- Department of Pharmacology, Xuanwu Hospital of Capital Medical University; Beijing Institute for Brain disorder; Beijing Engineering Research Center for Nerve System Drugs; Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
| | - Lan Zhang
- Department of Pharmacology, Xuanwu Hospital of Capital Medical University; Beijing Institute for Brain disorder; Beijing Engineering Research Center for Nerve System Drugs; Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
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16
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Rinaldi L, Sepe M, Donne RD, Feliciello A. A dynamic interface between ubiquitylation and cAMP signaling. Front Pharmacol 2015; 6:177. [PMID: 26388770 PMCID: PMC4559665 DOI: 10.3389/fphar.2015.00177] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/06/2015] [Indexed: 01/01/2023] Open
Abstract
Phosphorylation waves drive the propagation of signals generated in response to hormones and growth factors in target cells. cAMP is an ancient second messenger implicated in key biological functions. In mammals, most of the effects elicited by cAMP are mediated by protein kinase A (PKA). Activation of the kinase by cAMP results in the phosphorylation of a variety of cellular substrates, leading to differentiation, proliferation, survival, metabolism. The identification of scaffold proteins, namely A-Kinase Anchor proteins (AKAPs), that localize PKA in specific cellular districts, provided critical cues for our understanding of the role played by cAMP in cell biology. Multivalent complexes are assembled by AKAPs and include signaling enzymes, mRNAs, adapter molecules, receptors and ion channels. A novel development derived from the molecular analysis of these complexes nucleated by AKAPs is represented by the presence of components of the ubiquitin-proteasome system (UPS). More to it, the AKAP complex can be regulated by the UPS, eliciting relevant effects on downstream cAMP signals. This represents a novel, yet previously unpredicted interface between compartmentalized signaling and the UPS. We anticipate that impairment of these regulatory mechanisms could promote cell dysfunction and disease. Here, we will focus on the reciprocal regulation between cAMP signaling and UPS, and its relevance to human degenerative and proliferative disorders.
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Affiliation(s)
- Laura Rinaldi
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II , Naples, Italy
| | - Maria Sepe
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II , Naples, Italy
| | - Rossella Delle Donne
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II , Naples, Italy
| | - Antonio Feliciello
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II , Naples, Italy
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17
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Lin Y, Xu T, Teng H, Cui M. Anticancer activity of NOB1-targeted shRNA combination with TRAIL in epithelial ovarian cancer cells. INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY 2015; 8:10061-10071. [PMID: 26617713 PMCID: PMC4637528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/26/2015] [Indexed: 06/05/2023]
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) based strategy is a promising targeted therapeutic approach for the treatment of ovarian cancer. However, the effectiveness of the treatment remains limited due to the inherent or acquired resistance of tumor cells to TRAIL. Our previously study demonstrated that downregulation of NOB1 (NIN1/RPN12 binding protein 1 homolog) expression by a lentiviral short hairpin RNA (shRNA) delivery system (Lv/sh-NOB1) suppressed ovarian cancer growth. Here, Lv/sh-NOB1 and TRAIL were combined and tested the effects of this combination on ovarian cancer cells to identify more effective therapeutics against ovarian cancer by several in vitro experiments. Tumor growth ability in SKVO3 xenograft nude mice was also determined to define this combination treatment effect in tumorigenesis in vivo. In vitro assay showed that Lv/sh-NOB1 in combination with TRAIL treatment in ovarian cancer cell synergistically suppressed the proliferation and colony formation, as well as induced cell apoptosis and increased the activity of caspase-3, -8 and -9. In vivo assay showed that Lv/sh-NOB1 combination with TRAIL synergistically suppressed tumor growth of nude mice model. Importantly, we found that downregulation of NOB1 could upregulate DR5 expression and active MAPK pathway, which might contribute to increase sensitivity TRAIL to ovarian cancer cells. These findings suggested that Lv/sh-NOB1 combination with TRAIL treatment may be a potential treatment approach for ovarian cancer.
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Affiliation(s)
- Yang Lin
- Department of Obstetrics and Gynecology, The Second Hospital, Jilin University #218 Ziqiagn Street, Nanguan District, Changchun 130041, China
| | - Tianmin Xu
- Department of Obstetrics and Gynecology, The Second Hospital, Jilin University #218 Ziqiagn Street, Nanguan District, Changchun 130041, China
| | - Hong Teng
- Department of Obstetrics and Gynecology, The Second Hospital, Jilin University #218 Ziqiagn Street, Nanguan District, Changchun 130041, China
| | - Manhua Cui
- Department of Obstetrics and Gynecology, The Second Hospital, Jilin University #218 Ziqiagn Street, Nanguan District, Changchun 130041, China
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