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Chuang YT, Yen CY, Tang JY, Chang FR, Tsai YH, Wu KC, Chien TM, Chang HW. Protein phosphatase 2A modulation and connection with miRNAs and natural products. ENVIRONMENTAL TOXICOLOGY 2024; 39:3612-3627. [PMID: 38491812 DOI: 10.1002/tox.24199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/28/2024] [Accepted: 02/10/2024] [Indexed: 03/18/2024]
Abstract
Protein phosphatase 2A (PP2A), a heterotrimeric holoenzyme (scaffolding, catalytic, and regulatory subunits), regulates dephosphorylation for more than half of serine/threonine phosphosites and exhibits diverse cellular functions. Although several studies on natural products and miRNAs have emphasized their impacts on PP2A regulation, their connections lack systemic organization. Moreover, only part of the PP2A family has been investigated. This review focuses on the PP2A-modulating effects of natural products and miRNAs' interactions with potential PP2A targets in cancer and non-cancer cells. PP2A-modulating natural products and miRNAs were retrieved through a literature search. Utilizing the miRDB database, potential PP2A targets of these PP2A-modulating miRNAs for the whole set (17 members) of the PP2A family were retrieved. Finally, PP2A-modulating natural products and miRNAs were linked via a literature search. This review provides systemic directions for assessing natural products and miRNAs relating to the PP2A-modulating functions in cancer and disease treatments.
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Affiliation(s)
- Ya-Ting Chuang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Sciences, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ching-Yu Yen
- School of Dentistry, Taipei Medical University, Taipei, Taiwan
- Department of Oral and Maxillofacial Surgery, Chi-Mei Medical Center, Tainan, Taiwan
| | - Jen-Yang Tang
- School of Post-Baccalaureate Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Radiation Oncology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Fang-Rong Chang
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yi-Hong Tsai
- Department of Pharmacy and Master Program, College of Pharmacy and Health Care, Tajen University, Pingtung, Taiwan
| | - Kuo-Chuan Wu
- Department of Computer Science and Information Engineering, National Pingtung University, Pingtung, Taiwan
| | - Tsu-Ming Chien
- Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Hsueh-Wei Chang
- Department of Biomedical Science and Environmental Biology, PhD Program in Life Sciences, College of Life Science, Kaohsiung Medical University, Kaohsiung, Taiwan
- Center for Cancer Research, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
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Fu Y, Jia X, Yuan J, Yang Y, Zhang T, Yu Q, Zhou J, Wang T. Fam72a functions as a cell-cycle-controlled gene during proliferation and antagonizes apoptosis through reprogramming PP2A substrates. Dev Cell 2023; 58:398-415.e7. [PMID: 36868233 DOI: 10.1016/j.devcel.2023.02.006] [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: 04/20/2022] [Revised: 06/28/2022] [Accepted: 02/09/2023] [Indexed: 03/05/2023]
Abstract
The cell cycle is key to life. After decades of research, it is unclear whether any parts of this process have yet to be identified. Fam72a is a poorly characterized gene and is evolutionarily conserved across multicellular organisms. Here, we have found that Fam72a is a cell-cycle-regulated gene that is transcriptionally and post-transcriptionally regulated by FoxM1 and APC/C, respectively. Functionally, Fam72a directly binds to tubulin and both the Aα and B56 subunits of PP2A-B56 to modulate tubulin and Mcl1 phosphorylation, which in turn affects the progression of the cell cycle and signaling of apoptosis. Moreover, Fam72a is involved in early responses to chemotherapy, and it efficiently antagonizes various anticancer compounds such as CDK and Bcl2 inhibitors. Thus, Fam72a switches the tumor-suppressive PP2A to be oncogenic by reprogramming its substrates. These findings identify a regulatory axis of PP2A and a protein member in the cell cycle and tumorigenesis regulatory network in human cells.
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Affiliation(s)
- Yuan Fu
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China; Department of Thoracic Oncology, Tianjin Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin Lung Cancer Center, Tianjin Medical University, Tianjin 300070, China.
| | - Xiaofan Jia
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Jinwei Yuan
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Yuting Yang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Teng Zhang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Qiujing Yu
- Department of Immunology and Key Laboratory of Immune Microenvironment and Disease, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China
| | - Jun Zhou
- Department of Genetics and Cell Biology, State Key Laboratory of Medicinal Chemical Biology, Haihe Laboratory of Cell Ecosystem, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Ting Wang
- Department of Pharmacology and Tianjin Key Laboratory of Inflammation Biology, The Province and Ministry Co-sponsored Collaborative Innovation Center for Medical Epigenetics, School of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, China; Department of Thoracic Oncology, Tianjin Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin Lung Cancer Center, Tianjin Medical University, Tianjin 300070, China.
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Pharmacological Inhibition of PP2A Overcomes Nab-Paclitaxel Resistance by Downregulating MCL1 in Esophageal Squamous Cell Carcinoma (ESCC). Cancers (Basel) 2021; 13:cancers13194766. [PMID: 34638252 PMCID: PMC8507542 DOI: 10.3390/cancers13194766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/13/2021] [Accepted: 09/18/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Paclitaxel-based chemotherapy has been introduced to treat esophageal squamous cell carcinoma. While its initial efficacy has been clinically established, the development of resistance is inevitable. To understand the paclitaxel resistance mechanism, we developed nanoparticle albumin-bound paclitaxel (nab-PTX)-resistant esophageal squamous cell lines from their sensitive counterparts. We found that resistant cells express higher levels of protein phosphatase 2A (PP2A), oxidative phosphorylation, and anti-apoptotic protein MCL1 than their counterparts. Therapeutically, the PP2A inhibitor LB-100 synergistically sensitized resistant esophageal squamous cells to nab-PTX both in vitro and in vivo. Therefore, our data suggest that LB-100 may potentially overcome nab-PTX resistance in a clinical setting. Abstract Paclitaxel-based chemotherapy is a treatment option for advanced esophageal squamous cell carcinoma (ESCC). However, the development of chemoresistance leads to treatment failure, and the underlying mechanism remains elusive. We investigated the mechanisms of nanoparticle albumin-bound paclitaxel (nab-PTX) resistance by establishing three nab-PTX resistant ESCC cell lines. Proteomics analysis revealed higher oxidative phosphorylation (OXPHOS) in resistant cell line DR150 than in its parental cell line KYSE150, which is likely caused by stabilized anti-apoptotic protein MCL1. Additionally, we discovered the elevated activity of protein phosphatase 2A (PP2A), the phosphatase that dephosphorylates and stabilizes MCL1, in nab-PTX resistant cell lines. Pharmacological inhibition of PP2A with small molecule compound LB-100 decreased MCL1 protein level, caused more apoptosis in nab-PTX resistant ESCC cell lines than in the parental cells in vitro, and significantly inhibited the tumor growth of nab-PTX resistant xenografts in vivo. Moreover, LB-100 pretreatment partially restored nab-PTX sensitivity in the resistant cell lines and synergistically inhibited the tumor growth of nab-PTX resistant xenografts with nab-PTX. In summary, our study identifies a novel mechanism whereby elevated PP2A activity stabilizes MCL1 protein, increases OXPHOS, and confers nab-PTX resistance, suggesting that targeting PP2A is a potential strategy for reversing nab-PTX resistance in patients with advanced ESCC.
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Wang H, Guo M, Wei H, Chen Y. Targeting MCL-1 in cancer: current status and perspectives. J Hematol Oncol 2021; 14:67. [PMID: 33883020 PMCID: PMC8061042 DOI: 10.1186/s13045-021-01079-1] [Citation(s) in RCA: 143] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/14/2021] [Indexed: 12/13/2022] Open
Abstract
Myeloid leukemia 1 (MCL-1) is an antiapoptotic protein of the BCL-2 family that prevents apoptosis by binding to the pro-apoptotic BCL-2 proteins. Overexpression of MCL-1 is frequently observed in many tumor types and is closely associated with tumorigenesis, poor prognosis and drug resistance. The central role of MCL-1 in regulating the mitochondrial apoptotic pathway makes it an attractive target for cancer therapy. Significant progress has been made with regard to MCL-1 inhibitors, some of which have entered clinical trials. Here, we discuss the mechanism by which MCL-1 regulates cancer cell apoptosis and review the progress related to MCL-1 small molecule inhibitors and their role in cancer therapy.
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Affiliation(s)
- Haolan Wang
- Department of Oncology, NHC Key Laboratory of Cancer Proteomics, Laboratory of Structural Biology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Ming Guo
- Department of Oncology, NHC Key Laboratory of Cancer Proteomics, Laboratory of Structural Biology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Hudie Wei
- Department of Oncology, NHC Key Laboratory of Cancer Proteomics, Laboratory of Structural Biology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
| | - Yongheng Chen
- Department of Oncology, NHC Key Laboratory of Cancer Proteomics, Laboratory of Structural Biology, National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China. .,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
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Phosphatase PP2A enhances MCL-1 protein half-life in multiple myeloma cells. Cell Death Dis 2021; 12:229. [PMID: 33658484 PMCID: PMC7930201 DOI: 10.1038/s41419-020-03351-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 01/31/2023]
Abstract
Multiple myeloma (MM), a treatable but incurable malignancy, is characterized by the growth of clonal plasma cells in protective niches in the bone marrow. MM cells depend on expression of BCL-2 family proteins, in particular MCL-1, for survival. The regulation of MCL-1 is complex and cell type-dependent. Unraveling the exact mechanism by which MCL-1 is overexpressed in MM may provide new therapeutic strategies for inhibition in malignant cells, preferably limiting side effects in healthy cells. In this study, we reveal that one cause of overexpression could be stabilization of the MCL-1 protein. We demonstrate this in a subset of MM and diffuse large B cell lymphoma (DLBCL) cell lines and MM patient samples. We applied a phosphatase siRNA screen to identify phosphatases responsible for MCL-1 stabilization in MM, and revealed PP2A as the MCL-1 stabilizing phosphatase. Using the PP2A inhibitor okadaic acid, we validated that PP2A dephosphorylates MCL-1 at Ser159 and/or Thr163, and thereby stabilizes MCL-1 in MM cells with long MCL-1 half-life, but not in DLBCL cells. Combined kinase and phosphatase inhibition experiments suggest that the MCL-1 half-life in MM is regulated by the counteracting functions of JNK and PP2A. These findings increase the understanding of the mechanisms by which MCL-1 is post-translationally regulated, which may provide novel strategies to inhibit MCL-1 in MM cells.
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Li Y, Zhou D, Xu S, Rao M, Zhang Z, Wu L, Zhang C, Lin N. DYRK1A suppression restrains Mcl-1 expression and sensitizes NSCLC cells to Bcl-2 inhibitors. Cancer Biol Med 2020; 17:387-400. [PMID: 32587776 PMCID: PMC7309455 DOI: 10.20892/j.issn.2095-3941.2019.0380] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 02/03/2020] [Indexed: 12/16/2022] Open
Abstract
Objective: Mcl-1 overexpression confers acquired resistance to Bcl-2 inhibitors in non-small cell lung cancer (NSCLC), but no direct Mcl-1 inhibitor is currently available for clinical use. Thus, novel therapeutic strategies are urgently needed to target Mcl-1 and sensitize the anti-NSCLC activity of Bcl-2 inhibitors. Methods: Cell proliferation was measured using sulforhodamine B and colony formation assays, and apoptosis was detected with Annexin V-FITC staining. Gene expression was manipulated using siRNAs and plasmids. Real-time PCR and Western blot were used to measure mRNA and protein levels. Immunoprecipitation and immunofluorescence were used to analyze co-localization of dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A) and Mcl-1. Results: Suppression of DYRK1A resulted in reduced Mcl-1 expression in NSCLC cells, whereas overexpression of DYRK1A significantly increased Mcl-1 expression. Suppression of DYRK1A did not alter Mcl-1 mRNA levels, but did result in an accelerated degradation of Mcl-1 protein in NSCLC cells. Furthermore, DYRK1A mediated proteasome-dependent degradation of Mcl-1 in NSCLC cells, and DYRK1A co-localized with Mcl-1 in NSCLC cells and was co-expressed with Mcl-1 in tumor samples from lung cancer patients, suggesting that Mcl-1 may be a novel DYRK1A substrate. We showed that combined therapy with harmine and Bcl-2 antagonists significantly inhibited cell proliferation and induced apoptosis in NSCLC cell lines as well as primary NSCLC cells. Conclusions: Mcl-1 is a novel DYRK1A substrate, and the role of DYRK1A in promoting Mcl-1 stability makes it an attractive target for decreasing Bcl-2 inhibitor resistance.
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Affiliation(s)
- Yangling Li
- Department of Clinical Pharmacology, Hangzhou First People’s Hospital, Nanjing Medical University, Hangzhou 310006, China
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China
| | - Dongmei Zhou
- Department of Clinical Pharmacology, Hangzhou First People’s Hospital, Nanjing Medical University, Hangzhou 310006, China
| | - Shuang Xu
- Department of Clinical Pharmacology, Hangzhou First People’s Hospital, Nanjing Medical University, Hangzhou 310006, China
| | - Mingjun Rao
- Institute of Pharmacology, College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 311402, China
| | - Zuoyan Zhang
- School of Medicine, Zhejiang University City College, Hangzhou 310015, China
| | - Linwen Wu
- School of Medicine, Zhejiang University City College, Hangzhou 310015, China
| | - Chong Zhang
- School of Medicine, Zhejiang University City College, Hangzhou 310015, China
| | - Nengming Lin
- Department of Clinical Pharmacology, Hangzhou First People’s Hospital, Nanjing Medical University, Hangzhou 310006, China
- Department of Clinical Pharmacology, Key Laboratory of Clinical Cancer Pharmacology and Toxicology Research of Zhejiang Province, Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China
- Institute of Pharmacology, College of Pharmaceutical Sciences, Zhejiang Chinese Medical University, Hangzhou 311402, China
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Liu L, Shi X, Zhao H, Yang M, Wang C, Liao M, Zhao J. Nicotine induces cell survival and chemoresistance by stimulating Mcl-1 phosphorylation and its interaction with Bak in lung cancer. J Cell Physiol 2019; 234:15934-15940. [PMID: 30741422 DOI: 10.1002/jcp.28251] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/10/2019] [Accepted: 01/16/2019] [Indexed: 01/24/2023]
Abstract
Nicotine is a major carcinogen in cigarettes, which can enhance cell proliferation and metastasis and increase the chemoresistance of cancer cells. Our previous data found that nicotine promotes cell survival in lung cancer by affecting the expression of antiapoptotic protein Mcl-1, suggesting that the Mcl-1 may be a therapeutic target for patients with lung cancer. In this study, we found that the effects of drug resistance on nicotine-induced lung cancer cell lines were shown to influence the phosphorylation of Mcl-1. Moreover, nicotine induces Mcl-1 phosphorylation exclusively at the T163 site, which results in enhancement of the antiapoptotic activity of Mcl-1 and increased cell survival. Meanwhile, nicotine can reduce the sensitivity of H1299 cells to CDDP via enhancement of the binding of Mcl-1 to Bak, which inhibits the proapoptotic effect of Bak and ultimately leads to increased survival and drug resistance of lung cancer cells. Thus, nicotine-induced cell survival and chemoresistance may occur in a mechanism by stimulating Mcl-1 phosphorylation and its interaction with Bak, which may contribute to improving the efficacy of chemotherapy in the treatment of human lung cancer.
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Affiliation(s)
- Ling Liu
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Xiaqing Shi
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Huandong Zhao
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Manyi Yang
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Chengzhi Wang
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China.,Department of Nephrology Blood Purification Center, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Mingmei Liao
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jinfeng Zhao
- Key Laboratory of Nanobiological Technology of Chinese Ministry of Health, Xiangya Hospital, Central South University, Changsha, Hunan, China
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Uchida A, Isobe Y, Asano J, Uemura Y, Hoshikawa M, Takagi M, Miura I. Targeting BCL2 with venetoclax is a promising therapeutic strategy for "double-proteinexpression" lymphoma with MYC and BCL2 rearrangements. Haematologica 2018; 104:1417-1421. [PMID: 30523053 PMCID: PMC6601100 DOI: 10.3324/haematol.2018.204958] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/23/2018] [Indexed: 12/12/2022] Open
Abstract
The so-called “double-hit” and “double-protein-expression” lymphoma with MYC and BCL2 rearrangements is a rare, mature B-cell neoplasm characterized by a germinal center B-cell phenotype, abundant protein expression of MYC and BCL2, rapid disease progression, and a poor prognosis. In this study, we showed the potential benefit of the BCL2 inhibitor venetoclax in the treatment of this disease. Immunohistochemical studies of the lymphoma tissues confirmed that overexpression of MYC and BCL2 was observed more frequently in this subtype than in other germinal center B-cell-like diffuse large B-cell lymphomas. In contrast, another pro-survival protein MCL1 was less expressed in this subtype, even when compared with its expression in the non-“double-hit” and “double-protein-expression” type. Furthermore, in vitro studies using two “double-hit” and “double-protein-expression” lymphoma-derived cell lines, Karpas231 and OCI-Ly8, clearly showed that a low concentration of venetoclax, but not the MCL1 inhibitor S63845, was sufficient to induce apoptosis in the two lines, compared with in other germinal center B-cell-derived cell lines, BJAB and SU-DHL10. These results indicate that the survival of this type of lymphoma depends predominantly on BCL2 rather than on MCL1. Unexpectedly, we found that venetoclax not only disrupts the interaction between BCL2 and the pro-apoptotic protein BIM, but also leads to dephosphorylation of BCL2 and further downregulates MCL1 protein expression, probably through modulation of the protein phosphatase 2A B56α activity in Karpas231 and OCI-Ly8. Indeed, a low concentration of venetoclax induced substantial apoptosis in the primary lymphoma cells, regardless of high protein expression of MCL1 associated with venetoclax resistance. Venetoclax clearly triggers the signal transduction related to BCL2 and MCL1 in “double-hit” and “double-protein-expression” lymphoma cells.
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Affiliation(s)
- Akiko Uchida
- Division of Hematology and Oncology, Department of Internal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa
| | - Yasushi Isobe
- Division of Hematology and Oncology, Department of Internal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa
| | - Junko Asano
- Division of Hematology and Oncology, Department of Internal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa
| | - Yu Uemura
- Division of Hematology and Oncology, Department of Internal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa
| | - Masahiro Hoshikawa
- Department of Pathology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa, Japan
| | - Masayuki Takagi
- Department of Pathology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa, Japan
| | - Ikuo Miura
- Division of Hematology and Oncology, Department of Internal Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa
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González R, Molina-Ruiz FJ, Bárcena JA, Padilla CA, Muntané J. Regulation of Cell Survival, Apoptosis, and Epithelial-to-Mesenchymal Transition by Nitric Oxide-Dependent Post-Translational Modifications. Antioxid Redox Signal 2018; 29:1312-1332. [PMID: 28795583 DOI: 10.1089/ars.2017.7072] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SIGNIFICANCE Nitric oxide (NO) is a physiopathological messenger generating different reactive nitrogen species (RNS) according to hypoxic, acidic and redox conditions. Recent Advances: RNS and reactive oxygen species (ROS) promote relevant post-translational modifications, such as nitrosation, nitration, and oxidation, in critical components of cell proliferation and death, epithelial-to-mesenchymal transition, and metastasis. CRITICAL ISSUES The pro- or antitumoral properties of NO are dependent on local concentration, redox state, cellular status, duration of exposure, and compartmentalization of NO generation. The increased expression of NO synthase has been associated with cancer progression. However, the experimental strategies leading to high intratumoral NO generation have been shown to exert antitumoral properties. The effect of NO and ROS on cell signaling is critically altered by factors modulating tumor progression such as oxygen content, metabolism, and inflammatory response. The review describes the alteration of key components involved in cell survival and death, metabolism, and metastasis induced by RNS- and ROS-related post-translational modifications. FUTURE DIRECTIONS The identification of the molecular targets affected by nitrosation, nitration, and oxidation, as well as their interactions with other post-translational modifications, will improve the understanding on the complex signaling and cell fate decision in cancer. The therapeutic NO-based strategies have to address the complex crosstalk among NO and ROS with regard to critical components affecting tumor cell survival, metabolism, and metastasis in the progression of cancer, as well as close interaction with ionizing radiation and chemotherapy.
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Affiliation(s)
- Raúl González
- 1 Institute of Biomedicine of Seville (IBiS), IBiS/"Virgen del Rocío" University Hospital/CSIC/University of Seville , Seville, Spain
| | - Francisco J Molina-Ruiz
- 1 Institute of Biomedicine of Seville (IBiS), IBiS/"Virgen del Rocío" University Hospital/CSIC/University of Seville , Seville, Spain
| | - J Antonio Bárcena
- 2 Department of Biochemistry and Molecular Biology, Maimonides Biomedical Research Institute of Córdoba (IMIBIC), University of Córdoba , Córdoba, Spain
| | - C Alicia Padilla
- 2 Department of Biochemistry and Molecular Biology, Maimonides Biomedical Research Institute of Córdoba (IMIBIC), University of Córdoba , Córdoba, Spain
| | - Jordi Muntané
- 3 Department of General Surgery, "Virgen del Rocío" University Hospital/IBiS/CSIC/University of Seville , Seville, Spain .,4 Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) , Madrid, Spain
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10
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Song KA, Hosono Y, Turner C, Jacob S, Lochmann TL, Murakami Y, Patel NU, Ham J, Hu B, Powell KM, Coon CM, Windle BE, Oya Y, Koblinski JE, Harada H, Leverson JD, Souers AJ, Hata AN, Boikos S, Yatabe Y, Ebi H, Faber AC. Increased Synthesis of MCL-1 Protein Underlies Initial Survival of EGFR-Mutant Lung Cancer to EGFR Inhibitors and Provides a Novel Drug Target. Clin Cancer Res 2018; 24:5658-5672. [PMID: 30087143 DOI: 10.1158/1078-0432.ccr-18-0304] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 06/29/2018] [Accepted: 08/01/2018] [Indexed: 11/16/2022]
Abstract
Purpose: EGFR inhibitors (EGFRi) are effective against EGFR-mutant lung cancers. The efficacy of these drugs, however, is mitigated by the outgrowth of resistant cells, most often driven by a secondary acquired mutation in EGFR, T790M We recently demonstrated that T790M can arise de novo during treatment; it follows that one potential therapeutic strategy to thwart resistance would be identifying and eliminating these cells [referred to as drug-tolerant cells (DTC)] prior to acquiring secondary mutations like T790M Experimental Design: We have developed DTCs to EGFRi in EGFR-mutant lung cancer cell lines. Subsequent analyses of DTCs included RNA-seq, high-content microscopy, and protein translational assays. Based on these results, we tested the ability of MCL-1 BH3 mimetics to combine with EGFR inhibitors to eliminate DTCs and shrink EGFR-mutant lung cancer tumors in vivo Results: We demonstrate surviving EGFR-mutant lung cancer cells upregulate the antiapoptotic protein MCL-1 in response to short-term EGFRi treatment. Mechanistically, DTCs undergo a protein biosynthesis enrichment resulting in increased mTORC1-mediated mRNA translation of MCL-1, revealing a novel mechanism in which lung cancer cells adapt to short-term pressures of apoptosis-inducing kinase inhibitors. Moreover, MCL-1 is a key molecule governing the emergence of early EGFR-mutant DTCs to EGFRi, and we demonstrate it can be effectively cotargeted with clinically emerging MCL-1 inhibitors both in vitro and in vivo Conclusions: Altogether, these data reveal that this novel therapeutic combination may delay the acquisition of secondary mutations, therefore prolonging therapy efficacy. Clin Cancer Res; 24(22); 5658-72. ©2018 AACR.
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Affiliation(s)
- Kyung-A Song
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Yasuyuki Hosono
- Division of Molecular Therapeutics, Aichi Cancer Center Research Institute, Nagoya, Japan
| | - Crystal Turner
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Sheeba Jacob
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Timothy L Lochmann
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Yoshiko Murakami
- Department of Pathology and Molecular Diagnostics, Aichi Cancer Center, Nagoya, Japan
| | - Neha U Patel
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Jungoh Ham
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Bin Hu
- Department of Pathology, VCU School of Medicine, Richmond, Virginia
| | - Krista M Powell
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Colin M Coon
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Brad E Windle
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | - Yuko Oya
- Division of Molecular Therapeutics, Aichi Cancer Center Research Institute, Nagoya, Japan
| | | | - Hisashi Harada
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia
| | | | | | - Aaron N Hata
- Massachusetts General Hospital Cancer Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Sosipatros Boikos
- Division of Hematology, Oncology and Palliative Care, Virginia Commonwealth University, Massey Cancer Center, Richmond, Virginia
| | - Yasushi Yatabe
- Department of Pathology and Molecular Diagnostics, Aichi Cancer Center, Nagoya, Japan.,Precision Medicine Center, Aichi Cancer Center, Nagoya, Japan
| | - Hiromichi Ebi
- Division of Molecular Therapeutics, Aichi Cancer Center Research Institute, Nagoya, Japan. .,Precision Medicine Center, Aichi Cancer Center, Nagoya, Japan
| | - Anthony C Faber
- Philips Institute for Oral Health Research, VCU School of Dentistry and Massey Cancer Center, Richmond, Virginia.
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11
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Narla G, Sangodkar J, Ryder CB. The impact of phosphatases on proliferative and survival signaling in cancer. Cell Mol Life Sci 2018; 75:2695-2718. [PMID: 29725697 PMCID: PMC6023766 DOI: 10.1007/s00018-018-2826-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 03/24/2018] [Accepted: 04/23/2018] [Indexed: 02/06/2023]
Abstract
The dynamic and stringent coordination of kinase and phosphatase activity controls a myriad of physiologic processes. Aberrations that disrupt the balance of this interplay represent the basis of numerous diseases. For a variety of reasons, early work in this area portrayed kinases as the dominant actors in these signaling events with phosphatases playing a secondary role. In oncology, these efforts led to breakthroughs that have dramatically altered the course of certain diseases and directed vast resources toward the development of additional kinase-targeted therapies. Yet, more recent scientific efforts have demonstrated a prominent and sometimes driving role for phosphatases across numerous malignancies. This maturation of the phosphatase field has brought with it the promise of further therapeutic advances in the field of oncology. In this review, we discuss the role of phosphatases in the regulation of cellular proliferation and survival signaling using the examples of the MAPK and PI3K/AKT pathways, c-Myc and the apoptosis machinery. Emphasis is placed on instances where these signaling networks are perturbed by dysregulation of specific phosphatases to favor growth and persistence of human cancer.
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Affiliation(s)
| | - Jaya Sangodkar
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
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12
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Zhang Y, Ishida CT, Ishida W, Lo SFL, Zhao J, Shu C, Bianchetti E, Kleiner G, Sanchez-Quintero MJ, Quinzii CM, Westhoff MA, Karpel-Massler G, Canoll P, Siegelin MD. Combined HDAC and Bromodomain Protein Inhibition Reprograms Tumor Cell Metabolism and Elicits Synthetic Lethality in Glioblastoma. Clin Cancer Res 2018; 24:3941-3954. [PMID: 29764852 DOI: 10.1158/1078-0432.ccr-18-0260] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 04/19/2018] [Accepted: 05/10/2018] [Indexed: 11/16/2022]
Abstract
Purpose: Glioblastoma remains a challenge in oncology, in part due to tumor heterogeneity.Experimental Design: Patient-derived xenograft and stem-like glioblastoma cells were used as the primary model systems.Results: Based on a transcriptome and subsequent gene set enrichment analysis (GSEA), we show by using clinically validated compounds that the combination of histone deacetylase (HDAC) inhibition and bromodomain protein (BRD) inhibition results in pronounced synergistic reduction in cellular viability in patient-derived xenograft and stem-like glioblastoma cells. Transcriptome-based GSEA analysis suggests that metabolic reprogramming is involved with synergistic reduction of oxidative and glycolytic pathways in the combination treatment. Extracellular flux analysis confirms that combined HDAC inhibition and BRD inhibition blunts oxidative and glycolytic metabolism of cancer cells, leading to a depletion of intracellular ATP production and total ATP levels. In turn, energy deprivation drives an integrated stress response, originating from the endoplasmic reticulum. This results in an increase in proapoptotic Noxa. Aside from Noxa, we encounter a compensatory increase of antiapoptotic Mcl-1 protein. Pharmacologic, utilizing the FDA-approved drug sorafenib, and genetic inhibition of Mcl-1 enhanced the effects of the combination therapy. Finally, we show in orthotopic patient-derived xenografts of GBM, that the combination treatment reduces tumor growth, and that triple therapy involving the clinically validated compounds panobinostat, OTX015, and sorafenib further enhances these effects, culminating in a significant regression of tumors in vivoConclusions: Overall, these results warrant clinical testing of this novel, efficacious combination therapy. Clin Cancer Res; 24(16); 3941-54. ©2018 AACR.
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Affiliation(s)
- Yiru Zhang
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
| | - Chiaki Tsuge Ishida
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
| | - Wataru Ishida
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Sheng-Fu L Lo
- Department of Neurosurgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Junfei Zhao
- Department of Biomedical Informatics, Columbia University, New York, New York
| | - Chang Shu
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
| | - Elena Bianchetti
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
| | - Giulio Kleiner
- Department of Neurology, H. Houston Merritt Neuromuscular Research Center, Columbia University Medical Center, New York, New York
| | - Maria J Sanchez-Quintero
- Department of Neurology, H. Houston Merritt Neuromuscular Research Center, Columbia University Medical Center, New York, New York
| | - Catarina M Quinzii
- Department of Neurology, H. Houston Merritt Neuromuscular Research Center, Columbia University Medical Center, New York, New York
| | - Mike-Andrew Westhoff
- Department of Pediatrics and Adolescent Medicine, Ulm University Medical Center, Ulm, Germany
| | | | - Peter Canoll
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York
| | - Markus D Siegelin
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, New York.
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13
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Drug-resistance in doxorubicin-resistant FL5.12 hematopoietic cells: elevated MDR1, drug efflux and side-population positive and decreased BCL2-family member expression. Oncotarget 2017; 8:113013-113033. [PMID: 29348885 PMCID: PMC5762570 DOI: 10.18632/oncotarget.22956] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/20/2017] [Indexed: 12/20/2022] Open
Abstract
Chemotherapeutic drug treatment can result in the emergence of drug-resistant cells. By culturing an interleukin-3 (IL-3)-dependent cell line, FL5.12 cells in the presence of the chemotherapeutic drug doxorubicin, we isolated FL/Doxo cells which are multi-drug resistant. Increased levels of drug efflux were detected in FL/Doxo cells which could be inhibited by the MDR1 inhibitor verapamil but not by the MRP1 inhibitor MK571. The effects of TP53 and MEK1 were examined by infection of FL/Doxo cells with retroviruses encoding either a dominant negative TP-53 gene (FL/Doxo+ TP53 (DN) or a constitutively-activated MEK-1 gene (FL/Doxo + MEK1 (CA). Elevated MDR1 but not MRP1 mRNA transcripts were detected by quantitative RT-PCR in the drug-resistant cells while transcripts encoding anti-apoptotic genes such as: BCL2, BCLXL and MCL1 were observed at higher levels in the drug-sensitive FL5.12 cells. The percentage of cells that were side-population positive was increased in the drug-resistant cells compared to the parental line. Drug-resistance and side-positive population cells have been associated with cancer stem cells (CSC). Our studies suggest mechanisms which could allow the targeting of these molecules to prevent drug-resistance.
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14
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Ma B, Yuan Z, Zhang L, Lv P, Yang T, Gao J, Pan N, Wu Q, Lou J, Han C, Zhang B. Long non-coding RNA AC023115.3 suppresses chemoresistance of glioblastoma by reducing autophagy. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2017; 1864:1393-1404. [PMID: 28499919 DOI: 10.1016/j.bbamcr.2017.05.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/05/2017] [Accepted: 05/08/2017] [Indexed: 12/13/2022]
Abstract
Malignant glioma is an aggressive brain cancer that responds poorly to chemotherapy. However, the molecular mechanism underlying the development of chemoresistance in glioma is not well-understood. In this study, we show that long non-coding RNA AC023115.3 is induced by cisplatin in human glioblastoma cells and that elevated AC023115.3 promotes cisplatin-induced apoptosis by inhibiting autophagy. Further mechanistic studies revealed that AC023115.3 acts as a competing endogenous RNA for miR-26a and attenuates the inhibitory effect of miR-26a on GSK3β, a proline-directed serine-threonine kinase that promotes the degradation of Mcl1, leading to an increase in GSK3β and a decrease in autophagy. Additionally, we discovered that AC023115.3 improves chemosensitivity of glioma cells to cisplatin by regulating the miR-26a-GSK3β-Mcl1 pathway. Thus, these data indicate that the AC023115.3-miR-26a-GSK3β signalling axis plays an important role in reducing the chemoresistance of glioma.
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Affiliation(s)
- Binbin Ma
- Department of Neurosurgery, Second Affiliated Hospital, Institute of Cancer Stem Cell, Dalian Medical University, Dalian 116027, China
| | - Zhongbo Yuan
- Department of Neurosurgery, Second Affiliated Hospital, Institute of Cancer Stem Cell, Dalian Medical University, Dalian 116027, China
| | - Li Zhang
- Laboratory of Pathogenic Biology, College of Basic Medical Science, Dalian Medical University, Dalian 116027, China
| | - Peng Lv
- Research Center, Second Affiliated Hospital, Dalian Medical University, Dalian 116027, China
| | - Ting Yang
- Department of Neurosurgery, Second Affiliated Hospital, Institute of Cancer Stem Cell, Dalian Medical University, Dalian 116027, China
| | - Jinxia Gao
- Department of Anaesthesiology, Second Affiliated Hospital, Dalian Medical University, 116027, China
| | - Ning Pan
- Department of Anaesthesiology, Second Affiliated Hospital, Dalian Medical University, 116027, China
| | - Qiong Wu
- Department of Neurology of Dalian Municipal Central Hospital Affiliated, Dalian Medical University, 116033, China
| | - Jiacheng Lou
- Department of Neurosurgery, Second Affiliated Hospital, Institute of Cancer Stem Cell, Dalian Medical University, Dalian 116027, China
| | - Chuanchun Han
- Department of Neurosurgery, Second Affiliated Hospital, Institute of Cancer Stem Cell, Dalian Medical University, Dalian 116027, China.
| | - Bo Zhang
- Department of Neurosurgery, Second Affiliated Hospital, Institute of Cancer Stem Cell, Dalian Medical University, Dalian 116027, China.
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15
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Targeting sphingosine kinase 1 induces MCL1-dependent cell death in acute myeloid leukemia. Blood 2016; 129:771-782. [PMID: 27956387 DOI: 10.1182/blood-2016-06-720433] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 11/30/2016] [Indexed: 12/21/2022] Open
Abstract
Acute myeloid leukemia (AML) is an aggressive malignancy where despite improvements in conventional chemotherapy and bone marrow transplantation, overall survival remains poor. Sphingosine kinase 1 (SPHK1) generates the bioactive lipid sphingosine 1-phosphate (S1P) and has established roles in tumor initiation, progression, and chemotherapy resistance in a wide range of cancers. The role and targeting of SPHK1 in primary AML, however, has not been previously investigated. Here we show that SPHK1 is overexpressed and constitutively activated in primary AML patient blasts but not in normal mononuclear cells. Subsequent targeting of SPHK1 induced caspase-dependent cell death in AML cell lines, primary AML patient blasts, and isolated AML patient leukemic progenitor/stem cells, with negligible effects on normal bone marrow CD34+ progenitors from healthy donors. Furthermore, administration of SPHK1 inhibitors to orthotopic AML patient-derived xenografts reduced tumor burden and prolonged overall survival without affecting murine hematopoiesis. SPHK1 inhibition was associated with reduced survival signaling from S1P receptor 2, resulting in selective downregulation of the prosurvival protein MCL1. Subsequent analysis showed that the combination of BH3 mimetics with either SPHK1 inhibition or S1P receptor 2 antagonism triggered synergistic AML cell death. These results support the notion that SPHK1 is a bona fide therapeutic target for the treatment of AML.
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16
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Ruiz-Medina BE, Ross JA, Kirken RA. Interleukin-2 Receptor β Thr-450 Phosphorylation Is a Positive Regulator for Receptor Complex Stability and Activation of Signaling Molecules. J Biol Chem 2015; 290:20972-20983. [PMID: 26152718 DOI: 10.1074/jbc.m115.660654] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Indexed: 02/02/2023] Open
Abstract
T, B, and natural killer cells are required for normal immune response and are regulated by cytokines such as IL-2. These cell signals are propagated following receptor-ligand engagement, controlling recruitment and activation of effector proteins. The IL-2 receptor β subunit (IL-2Rβ) serves in this capacity and is known to be phosphorylated. Tyrosine phosphorylation of the β chain has been studied extensively. However, the identification and putative regulatory roles for serine and threonine phosphorylation sites have yet to be fully characterized. Using LC-MS/MS and phosphospecific antibodies, a novel IL-2/IL-15 inducible IL-2Rβ phosphorylation site (Thr-450) was identified. IL-2 phosphokinetic analysis revealed that phosphorylation of IL-2Rβ Thr-450 is rapid (2.5 min), transient (peaks at 15 min), and protracted compared with receptor tyrosine phosphorylation and occurs in multiple cell types, including primary human lymphocytes. Pharmacological and siRNA-mediated inhibition of various serine/threonine kinases revealed ERK1/2 as a positive regulator, whereas purified protein phosphatase 1 (PP1), dephosphorylated Thr-450 in vitro. Reconstitution assays demonstrated that Thr-450 is important for regulating IL-2R complex formation, recruitment of JAK3, and activation of AKT and ERK1/2 and a transcriptionally active STAT5. These results provide the first evidence of the identification and functional characterization for threonine phosphorylation of an interleukin receptor.
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Affiliation(s)
- Blanca E Ruiz-Medina
- Department of Biological Sciences and Border Biomedical Research Center, The University of Texas at El Paso, El Paso, Texas 79968
| | - Jeremy A Ross
- Department of Biological Sciences and Border Biomedical Research Center, The University of Texas at El Paso, El Paso, Texas 79968
| | - Robert A Kirken
- Department of Biological Sciences and Border Biomedical Research Center, The University of Texas at El Paso, El Paso, Texas 79968.
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