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Liang J, Yun D, Jin W, Fan J, Wang X, Wang X, Li Y, Yu S, Zhang C, Li T, Yang X. NCAPH serves as a prognostic factor and promotes the tumor progression in glioma through PI3K/AKT signaling pathway. Mol Cell Biochem 2024:10.1007/s11010-024-04976-4. [PMID: 38587786 DOI: 10.1007/s11010-024-04976-4] [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: 09/26/2023] [Accepted: 02/24/2024] [Indexed: 04/09/2024]
Abstract
Non-SMC (Structural Maintenance of Chromosomes) condensin I complex subunit H (NCAPH) has been shown to facilitate progression and predict adverse prognostic outcome in many cancer types. However, the function of NCAPH in gliomas is still unclear. Series of experiments were taken to uncover the function of NCAPH in glioma. The expression of NCAPH and potential mechanism regulating progression of glioma was verified by bioinformatics analysis. Lentiviral transfection was used for establishment of loss-of-function and gain-of-function cell lines. CCK-8 assay and Colony-formation assay were used to evaluate proliferation. Transwell assay and Cell wound healing assay were used to assess migration and invasion. Cell cycle and apoptosis were measured by flow cytometry. Protein and RNA were quantified by WB and RT-PCR, respectively. The nude mice model of glioma was used to evaluate the effect of NCAPH in vivo. The expression of NCAPH increased significantly in glioma tissues and correlated with WHO grade, IDH wild-type and non-1p/19q codeletion. Glioma patients with high expression of NCAPH had an undesirable prognosis. Functionally, upregulated NCAPH promotes the malignant hallmarks of glioma cells in vivo and in vitro. NCAPH correlated with DNA damage repair ability of glioma cells and facilitated the proliferation, invasion, and migration of glioma cells by promoting the PI3K/AKT signaling pathway. This study identifies the important pro-tumor role of NCAPH in glioma and suggests that NCAPH is a potential therapeutic target.
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Affiliation(s)
- Jianshen Liang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Debo Yun
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
- Department of Neurosurgery, Nanchong Central Hospital, Nanchong, 637000, Sichuan, China
| | - Wenzhe Jin
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
- Department of Neurosurgery, Affiliated Hospital of Hebei University, Baoding, 071000, Hebei, China
| | - Jikang Fan
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Xuya Wang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Xisen Wang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Yiming Li
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Shengping Yu
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Chen Zhang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China
| | - Tao Li
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China.
| | - Xuejun Yang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, 300000, China.
- Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Tianjin, 300000, China.
- Department of Neurosurgery, Tsinghua University Beijing Tsinghua Changgung Hospital, Beijing, 102218, China.
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2
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Sun X, Zhang B, Luo L, Yang Y, He B, Zhang Q, Wang L, Xu S, Zheng P, Zhu W. Design, synthesis and pharmacological evaluation of 2-arylurea-1,3,5-triazine derivative (XIN-9): A novel potent dual PI3K/mTOR inhibitor for cancer therapy. Bioorg Chem 2022; 129:106157. [PMID: 36209563 DOI: 10.1016/j.bioorg.2022.106157] [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: 07/10/2022] [Revised: 08/25/2022] [Accepted: 09/12/2022] [Indexed: 01/03/2023]
Abstract
Blocking the PI3K/AKT/mTOR pathway has been widely recognized as an attractive cancer therapeutic strategy because of its crucial role in cell growth and survival. In this study, a novel series of 2-arylurea-1,3,5-triazine derivatives had been synthesized and evaluated as highly potent PI3K and mTOR inhibitors. The new compounds exhibited cytotoxic activities against MCF-7, Hela and A549 cancer cell lines (IC50 = 0.03-36.54 μM). The most promising compound XIN-9 exhibited potent inhibition against PI3K and mTOR kinase (IC50 = 23.8 and 10.9 nM). Mechanistic study using real-time PCR revealed the ability of XIN-9 to inhibit PI3K and mTOR. In addition, compound XIN-9 arrested the cell cycle of MCF-7 cells at the G0/G1 phase. XIN-9 also caused a significant dose-dependent increase of early and late apoptotic events. Molecular docking analysis revealed a high binding affinity for XIN-9 toward PI3K and mTOR. Following in vitro studies, XIN-9 was further evaluated in MCF-7 xenograft models to show significant in vivo anticancer efficacies with tumor growth inhibitions of 41.67% (po, 75 mg/kg). Overall, this work indicated that compound XIN-9 represents a potential anticancer targeting PI3K/AKT/mTOR pathway.
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Affiliation(s)
- Xin Sun
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China
| | - Binliang Zhang
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China; School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510000, China
| | - Leixuan Luo
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China
| | - Yang Yang
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China
| | - Bin He
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China
| | - Qian Zhang
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China; School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510000, China
| | - Linxiao Wang
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China
| | - Shan Xu
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China.
| | - Pengwu Zheng
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China.
| | - Wufu Zhu
- Jiangxi Provincial Key Laboratory of Drug Design and Evaluation, School of Pharmacy, Jiangxi Science & Technology Normal University, 605 Fenglin Road, Nanchang, Jiangxi 330013, China.
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3
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Yoon TW, Kim YI, Cho H, Brand DD, Rosloniec EF, Myers LK, Postlethwaite AE, Hasty KA, Stuart JM, Yi AK. Ameliorating effects of Gö6976, a pharmacological agent that inhibits protein kinase D, on collagen-induced arthritis. PLoS One 2019; 14:e0226145. [PMID: 31809526 PMCID: PMC6897462 DOI: 10.1371/journal.pone.0226145] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/20/2019] [Indexed: 12/16/2022] Open
Abstract
Toll-like receptor (TLR) signaling can contribute to the pathogenesis of arthritis. Disruption of TLR signaling at early stages of arthritis might thereby provide an opportunity to halt the disease progression and ameliorate outcomes. We previously found that Gö6976 inhibits TLR-mediated cytokine production in human and mouse macrophages by inhibiting TLR-dependent activation of protein kinase D1 (PKD1), and that PKD1 is essential for proinflammatory responses mediated by MyD88-dependent TLRs. In this study, we investigated whether PKD1 contributes to TLR-mediated proinflammatory responses in human synovial cells, and whether Gö6976 treatment can suppress the development and progression of type II collagen (CII)-induced arthritis (CIA) in mouse. We found that TLR/IL-1R ligands induced activation of PKD1 in human fibroblast-like synoviocytes (HFLS). TLR/IL-1R-induced expression of cytokines/chemokines was substantially inhibited in Gö6976-treated HFLS and PKD1-knockdown HFLS. In addition, serum levels of anti-CII IgG antibodies, and the incidence and severity of arthritis after CII immunization were significantly reduced in mice treated daily with Gö6976. Synergistic effects of T-cell receptor and TLR, as well as TLR alone, on spleen cell proliferation and cytokine production were significantly inhibited in the presence of Gö6976. Our results suggest a possibility that ameliorating effects of Gö6976 on CIA may be due to its ability to inhibit TLR/IL-1R-activated PKD1, which might play an important role in proinflammatory responses in arthritis, and that PKD1 could be a therapeutic target for inflammatory arthritis.
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Affiliation(s)
- Tae Won Yoon
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Young-In Kim
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Hongsik Cho
- Department of Orthopedic Surgery and Biomedical Engineering, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - David D. Brand
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Veterans Affairs Medical Center-Memphis, Memphis, Tennessee, United States of America
| | - Edward F. Rosloniec
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Veterans Affairs Medical Center-Memphis, Memphis, Tennessee, United States of America
| | - Linda K. Myers
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Arnold E. Postlethwaite
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Veterans Affairs Medical Center-Memphis, Memphis, Tennessee, United States of America
| | - Karen A. Hasty
- Department of Orthopedic Surgery and Biomedical Engineering, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Veterans Affairs Medical Center-Memphis, Memphis, Tennessee, United States of America
| | - John M. Stuart
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- Veterans Affairs Medical Center-Memphis, Memphis, Tennessee, United States of America
| | - Ae-Kyung Yi
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
- * E-mail:
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4
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Chen J, Chen Z, Huang Z, Yu H, Li Y, Huang W. Formiminotransferase Cyclodeaminase Suppresses Hepatocellular Carcinoma by Modulating Cell Apoptosis, DNA Damage, and Phosphatidylinositol 3-Kinases (PI3K)/Akt Signaling Pathway. Med Sci Monit 2019; 25:4474-4484. [PMID: 31203308 PMCID: PMC6592141 DOI: 10.12659/msm.916202] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background Formiminotransferase cyclodeaminase (FTCD) is a candidate tumor suppressor gene in hepatocellular carcinoma (HCC). However, the mechanism for reduced expression of FTCD and its functional role in HCC remains unclear. In this study, we explored the biological functions of FTCD in HCC. Material/Methods The expression and clinical correlation of FTCD in HCC tissue were analyzed using TCGA (The Cancer Genome Atlas) and a cohort of 60 HCC patients. The MEXPRESS platform was accessed to identify the methylation level in promoter region FTCD. CCK-8 assay and flow cytometry analysis were used to explore the proliferation, cell apoptosis proportion, and DNA damage in HCC cells with FTCD overexpression. Western blot analysis was performed to identify the downstream target of FTCD. Results FTCD is significantly downregulated in HCC tissues and cell lines. Low FTCD expression is correlated with a poor prognosis (P<0.001) and an aggressive tumor phenotype, including AFP levels (P=0.009), tumor size (P=0.013), vascular invasion (P=0.001), BCLC stage (P=0.024), and pTNM stage (P<0.001). Bioinformatics analysis indicated promoter hypermethylation can result in decreased expression of FTCD. FTCD overexpression suppressed cell proliferation by promoting DNA damage and inducing cell apoptosis in HCC cells. FTCD overexpression resulted in increased level of PTEN protein, but a decrease in PI3K, total Akt, and phosphorylated Akt protein in HCC cells, suggesting involvement of the PI3K/Akt pathway. Conclusions FTCD acts as a tumor suppressor gene in HCC pathogenesis and progression and is a candidate prognostic marker and a possible therapeutic target for this disease.
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Affiliation(s)
- Jiajia Chen
- National Key Discipline of Human Anatomy, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China (mainland).,Department of General Surgery, Affiliated Chaozhou Central Hospital, Southern Medical University, Chaozhou, Guangdong, China (mainland).,Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China (mainland)
| | - Zemian Chen
- Department of Medical Oncology, Affiliated Chaozhou Central Hospital, Southern Medical University, Chaozhou, Guangdong, China (mainland)
| | - Zhentian Huang
- Department of General Surgery, Affiliated Chaozhou Central Hospital, Southern Medical University, Chaozhou, Guangdong, China (mainland)
| | - Hongrong Yu
- Department of Human Anatomy, School of Preclinical Medicine, Guangxi Medical University, Nanning, Guangxi, China (mainland)
| | - Yanbing Li
- National Key Discipline of Human Anatomy, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China (mainland)
| | - Wenhua Huang
- National Key Discipline of Human Anatomy, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China (mainland).,Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China (mainland)
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5
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Deng S, Nie ZG, Peng PJ, Liu Y, Xing S, Long LS, Peng H. Decrease of GSK3β Ser-9 Phosphorylation Induced Osteoblast Apoptosis in Rat Osteoarthritis Model. Curr Med Sci 2019; 39:75-80. [DOI: 10.1007/s11596-019-2002-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 11/30/2018] [Indexed: 12/16/2022]
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6
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Karantanos T, Moliterno AR. The roles of JAK2 in DNA damage and repair in the myeloproliferative neoplasms: Opportunities for targeted therapy. Blood Rev 2018; 32:426-432. [PMID: 29627078 DOI: 10.1016/j.blre.2018.03.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 03/03/2018] [Accepted: 03/27/2018] [Indexed: 02/09/2023]
Abstract
The JAK2V617F-positive myeloproliferative neoplasms (MPN) serve as an excellent model for the study of genomic instability accumulation during cancer progression. Recent studies highlight the implication of JAK2 activating mutations in the development of DNA damage via reactive oxygen species (ROS) production, replication stress induction and the accumulation of genomic instability via the increased degradation of p53 and acquisition of a "mutagenic" phenotype. The accumulation of genomic instability and acquisition of mutations in critical DNA damage repair (DDR) mediators appears to be implicated in the progression of JAK2V617F-positive MPN. On the other hand, JAK2 signaling normally induces DDR through activation of repair mediators such as Chk1, RAD51 and RECQL5. These opposing effects on DNA integrity in the setting of JAK2V617F have significant clinical implications and have led to the introduction of novel combinational therapies for these diseases. The inhibition of MDM2 with Nutlin-3 improves the efficacy of IFN-α via decreased p53 degradation, the combination of hydroxyurea with Ruxolitinib, and their combination with PARP inhibitors have significant anti-tumor effects. A better understanding of the implication of JAK2 in the development and repair of DNA damage can improve our understanding of the biology of these neoplasms, meliorate the risk stratification of our patients and enrich our therapeutic armamentarium.
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Affiliation(s)
| | - Alison R Moliterno
- Division of Hematology, Department of Medicine, The Johns Hopkins University School of Medicine, USA.
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7
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Umezawa Y, Kurosu T, Akiyama H, Wu N, Nogami A, Nagao T, Miura O. Down regulation of Chk1 by p53 plays a role in synergistic induction of apoptosis by chemotherapeutics and inhibitors for Jak2 or BCR/ABL in hematopoietic cells. Oncotarget 2018; 7:44448-44461. [PMID: 27286446 PMCID: PMC5190110 DOI: 10.18632/oncotarget.9844] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 05/20/2016] [Indexed: 01/17/2023] Open
Abstract
DNA-damaging chemotherapeutic agents activate apoptotic pathways in cancer cells. However, they also activate checkpoint mechanisms mainly involving Chk1 and p53 to arrest cell cycle progression, thus abbreviating their cytotoxic effects. We previously found that aberrant tyrosine kinases involved in leukemogenesis, such as BCR/ABL and Jak2-V617F, as well as Jak2 activated by hematopoietic cytokines enhance Chk1-mediated G2/M arrest through the PI3K/Akt/GSK3 pathway to confer resistance to chemotherapeutic agents, which was prevented by inhibition of these kinases or the downstream PI3K/Akt pathway. However, the possible involvement of p53 in regulation of Chk1-mediated G2/M checkpoint has remained to be elucidated. We demonstrate here that a dominant negative mutant of p53, p53-DD, increases Chk1-mediated G2/M checkpoint activation induced by chemotherapeutics and protects it from down regulation by inhibition of Jak2, BCR/ABL, or the PI3K/Akt pathway in hematopoietic model cell lines 32D and BaF3 or their transformants by BCR/ABL. Consistent with this, the p53 activator nutlin-3 synergistically induced apoptosis with chemotherapeutics by inhibiting Chk1-mediated G2/M arrest in these cells, including cells transformed by the T315I mutant of BCR/ABL resistant to various kinase inhibitors in clinical use. Further studies suggest that p53 may inhibit the Chk1 pathway by its transcription-dependent function and through mechanisms involving the proteasomal system, but not the PI3K/Akt/GSK3 pathway. The present study may shed a new light on molecular mechanisms for the therapy resistance of p53-mutated hematological malignancies and would provide valuable information for the development of novel therapeutic strategies against these diseases with dismal prognosis.
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Affiliation(s)
- Yoshihiro Umezawa
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuya Kurosu
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Hiroki Akiyama
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Nang Wu
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Ayako Nogami
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Toshikage Nagao
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
| | - Osamu Miura
- Department of Hematology, Graduate School of Medical and Dental Sciences, and Graduate School of Biomedical Science, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
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8
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Jadali A, Ying YLM, Kwan KY. Activation of CHK1 in Supporting Cells Indirectly Promotes Hair Cell Survival. Front Cell Neurosci 2017; 11:137. [PMID: 28572758 PMCID: PMC5435747 DOI: 10.3389/fncel.2017.00137] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 04/21/2017] [Indexed: 12/15/2022] Open
Abstract
The sensory hair cells of the inner ear are exquisitely sensitive to ototoxic insults. Loss of hair cells after exposure to ototoxic agents causes hearing loss. Chemotherapeutic agents such as cisplatin causes hair cell loss. Cisplatin forms DNA mono-adducts as well as intra- and inter-strand DNA crosslinks. DNA cisplatin adducts are repaired through the DNA damage response. The decision between cell survival and cell death following DNA damage rests on factors that are involved in determining damage tolerance, cell survival and apoptosis. Cisplatin damage on hair cells has been the main focus of many ototoxic studies, yet the effect of cisplatin on supporting cells has been largely ignored. In this study, the effects of DNA damage response in cochlear supporting cells were interrogated. Supporting cells play a major role in the development, maintenance and oto-protection of hair cells. Loss of supporting cells may indirectly affect hair cell survival or maintenance. Activation of the Phosphoinositide 3-Kinase (PI3K) signaling was previously shown to promote hair cell survival. To test whether activating PI3K signaling promotes supporting cell survival after cisplatin damage, cochlear explants from the neural subset (NS) Cre Pten conditional knockout mice were employed. Deletion of Phosphatase and Tensin Homolog (PTEN) activates PI3K signaling in multiple cell types within the cochlea. Supporting cells lacking PTEN showed increased cell survival after cisplatin damage. Supporting cells lacking PTEN also showed increased phosphorylation of Checkpoint Kinase 1 (CHK1) levels after cisplatin damage. Nearest neighbor analysis showed increased numbers of supporting cells with activated PI3K signaling in close proximity to surviving hair cells in cisplatin damaged cochleae. We propose that increased PI3K signaling promotes supporting cell survival through phosphorylation of CHK1 and increased survival of supporting cells indirectly increases hair cell survival after cisplatin damage.
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Affiliation(s)
- Azadeh Jadali
- Department of Cell Biology and Neuroscience, Rutgers UniversityPiscataway, NJ, USA.,Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers UniversityPiscataway, NJ, USA.,3D BiotekBridgewater, NJ, USA
| | - Yu-Lan M Ying
- Department of Otolaryngology-Head and Neck Surgery, Rutgers New Jersey Medical SchoolNewark, NJ, USA
| | - Kelvin Y Kwan
- Department of Cell Biology and Neuroscience, Rutgers UniversityPiscataway, NJ, USA.,Stem Cell Research Center and Keck Center for Collaborative Neuroscience, Rutgers UniversityPiscataway, NJ, USA
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9
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Lee KI, Su CC, Yang CY, Hung DZ, Lin CT, Lu TH, Liu SH, Huang CF. Etoposide induces pancreatic β-cells cytotoxicity via the JNK/ERK/GSK-3 signaling-mediated mitochondria-dependent apoptosis pathway. Toxicol In Vitro 2016; 36:142-152. [PMID: 27473919 DOI: 10.1016/j.tiv.2016.07.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 04/18/2016] [Accepted: 07/25/2016] [Indexed: 01/10/2023]
Abstract
Etoposide is widely used in the treatment of the different types of tumors such as pancreatic cancer. However, etoposide also causes several unwanted side-effects in normal viable cells, including pancreatic β-cells, which are vulnerable to chemical-induced injuries, and the molecular mechanisms underlying etoposide-induced apoptosis are still unclear. Here, the results showed that in RIN-m5F cells (a β-cell-derived cell line), the number of viable cells was significantly decreased after 24h of etoposide treatment and underwent mitochondria-dependent apoptotic signals accompanied by mitochondrial dysfunction, and increases in the population of sub-G1 hypodiploid cells and apoptotic cells, caspase-3 activity, and the activation of caspase cascades. Etoposide also increased the phosphorylation levels of glycogen synthase kinase (GSK)-3α/β in treated RIN-m5F cells. Pretreatment with LiCl, a GSK-3 inhibitor, prevented etoposide-induced mitochondria-dependent apoptosis and GSK-3 protein phosphorylation in RIN-m5F cells. Furthermore, exposure of the cells to etoposide induced the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-related kinase (ERK)1/2 but not p38-MAPK, which was suppressed by the specific JNK inhibitor (SP600125) and ERK1/2 inhibitor (PD98059), respectively. Additionally, pretreatment with both SP600125 and PD98059 effectively suppressed etoposide-induced β-cell cytotoxicity, apoptosis, and GSK-3 protein phosphorylation; however, LiCl did not reverse JNK and ERK1/2 phosphorylation. Taken together, these results suggest that etoposide is capable of causing cytotoxicity on pancreatic β-cells by inducing apoptosis through the JNK/ERK-mediated GSK-3 downstream-triggered mitochondria-dependent signaling pathway.
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Affiliation(s)
- Kuan-I Lee
- Department of Emergency, Taichung Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Taichung 427, Taiwan
| | - Chin-Chuan Su
- Graduate Institute of Basic Medical Science, College of Medicine, China Medical University, Taichung 404, Taiwan; Department of Otorhinolaryngology, Head and Neck Surgery, Changhua Christian Hospital, Changhua County 500, Taiwan
| | - Ching-Yao Yang
- Department of Surgery, National Taiwan University Hospital, Taipei 100, Taiwan; Department of Surgery, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Dong-Zong Hung
- Division of Toxicology, Trauma & Emergency Center, China Medical University Hospital, Taichung 404, Taiwan
| | - Ching-Ting Lin
- School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan
| | - Tien-Hui Lu
- Department of Physiology, and Graduate Institute of Basic Medical Science, College of Medicine, China Medical University, Taichung 404, Taiwan
| | - Shing-Hwa Liu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan.
| | - Chun-Fa Huang
- School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung 404, Taiwan; Department of Nursing, College of Medical and Health Science, Asia University, Taichung 413, Taiwan.
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10
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Zhang D, Piao HL, Li YH, Qiu Q, Li DJ, Du MR, Tsang BK. Inhibition of AKT sensitizes chemoresistant ovarian cancer cells to cisplatin by abrogating S and G2/M arrest. Exp Mol Pathol 2016; 100:506-13. [PMID: 27163202 DOI: 10.1016/j.yexmp.2016.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 04/15/2016] [Accepted: 05/02/2016] [Indexed: 10/21/2022]
Abstract
The phosphatidylinositol 3-kinase (PI3K)/Akt pathway is frequently altered in human malignancies and Akt over-expression and/or activation induces malignant transformation and chemoresistance. However, the role of Akt in the mechanisms of chemoresistance remains elusive. Here we reported that cisplatin treatment of chemosensitive, but not resistant, ovarian cancer cells (OVCAs) markedly increased the cell proportion in sub-G1 phase. Cisplatin however caused a significant accumulation of the resistant cells in S and G2/M phases, which was associated with a rapid and sustained checkpoint kinase 1 (Chk1) activation. In contrast, while cisplatin also elicited a rapid activation of Chk1 in sensitive cells, it markedly decreased total ChK1 and phospho-Chk1 contents over 12 h. Over-expression of dominant negative (DN)-AKT alone increased phospho-Chk1 content, and induced G2/M arrest and apoptosis. However, it inhibited Chk1 activation and G2/M arrest with combination of cisplatin treatment, resulting in p53-independent apoptosis. Furthermore, the responses of the chemoresistant cells to cisplatin were attenuated with forced expression of constitutive active AKT2. Chk1 knock-down also facilitated cisplatin-induced apoptosis in chemoresistant cells. Our studies implicate that, in addition to its cell survival and anti-apoptotic actions, Akt might also play an important role in the regulation of G2-M transition, possibly via up-regulation of Chk1 activity and stability. These data provide strong support for the concept that Akt is important in cell cycle regulation in the control of chemosensitivity in OVCAs and offers an alternate regulatory pathway for the development of rationale therapy for cisplatin-resistant ovarian cancer.
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Affiliation(s)
- Di Zhang
- Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical College, Shanghai, 200011, China; Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, 200011, China
| | - Hai-Lan Piao
- Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical College, Shanghai, 200011, China; Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, 200011, China
| | - Yan-Hong Li
- Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical College, Shanghai, 200011, China; Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, 200011, China
| | - Qing Qiu
- Department of Obstetrics and Gynecology, and Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Canada; Department of Cellular and Molecular Medicine, and Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Da-Jin Li
- Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical College, Shanghai, 200011, China; Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, 200011, China
| | - Mei-Rong Du
- Laboratory for Reproductive Immunology, Hospital and Institute of Obstetrics and Gynecology, Fudan University Shanghai Medical College, Shanghai, 200011, China; Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases, Shanghai, 200011, China; Department of Obstetrics and Gynecology, and Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Canada.
| | - Benjamin K Tsang
- State Key Laboratory of Quality Research in Chinese Medicine and the Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Macau; Department of Obstetrics and Gynecology, and Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Canada; Department of Cellular and Molecular Medicine, and Interdisciplinary School of Health Sciences, University of Ottawa, Ottawa, Canada; Chronic Disease Program, Ottawa Hospital Research Institute, Ottawa, Canada.
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11
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Zhou X, Ma X, Wang Z, Sun C, Wang Y, He Y, Zhang H. Radiation-induced hyperproliferation of intestinal crypts results in elevated genome instability with inactive p53-related genomic surveillance. Life Sci 2015; 143:80-8. [PMID: 26514305 DOI: 10.1016/j.lfs.2015.10.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Revised: 10/20/2015] [Accepted: 10/23/2015] [Indexed: 12/12/2022]
Abstract
AIMS Radiation-induced hyperproliferation of intestinal crypts is well documented, but its potential tumorigenic effects remain elusive. Here we aim to determine the genomic surveillance process during crypt hyperproliferation, and its consequential outcome after ionizing radiation. MAIN METHODS Crypt regeneration in the intestine was induced by a single dose of 12Gy abdominal irradiation. γ-H2AX, 53BP1 and DNA-PKcs were used as DNA repair surrogates to investigate the inherent ability of intestinal crypt cells to recognize and repair double-strand breaks. Ki67 staining and the 5-bromo-2'-deoxyuridine incorporation assay were used to study patterns of cell proliferation in regenerating crypts. Staining for ATM, p53, Chk1 and Chk2 was performed to study checkpoint activation and release. Apoptosis was evaluated through H&E staining and terminal deoxynucleotidyl transferase (dUTP) nick-end labeling. KEY FINDINGS The ATM-p53 pathway was immediately activated after irradiation. A second wave of DSBs in crypt cells was observed in regenerating crypts, accompanied with significantly increased chromosomal bridges. The p53-related genomic surveillance pathway was not active during the regeneration phase despite DSBs and chromosomal bridges in the cells of regenerating crypts. Non-homologous end joining (NHEJ) DSBs repair was involved in the DSBs repair process, as indicated by p-DNA-PKcs staining. SIGNIFICANCE Intestinal crypt cells retained hyperproliferation with inactive p53-related genomic surveillance system. NHEJ was involved in the resultant genomic instability during hyperproliferation.
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Affiliation(s)
- Xin Zhou
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, PR China
| | - Xiaofei Ma
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; The School of Nuclear Science and Technology, Lanzhou University, Lanzhou 730000, PR China; Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, PR China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 10049, PR China; The National Laboratory for the Heavy Ion Research Facility in Lanzhou, Lanzhou 730000, PR China
| | - Zhenhua Wang
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, PR China
| | - Chao Sun
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, PR China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 10049, PR China
| | - Yupei Wang
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 10049, PR China; The National Laboratory for the Heavy Ion Research Facility in Lanzhou, Lanzhou 730000, PR China
| | - Yang He
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 10049, PR China; The National Laboratory for the Heavy Ion Research Facility in Lanzhou, Lanzhou 730000, PR China
| | - Hong Zhang
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China; Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, PR China; The National Laboratory for the Heavy Ion Research Facility in Lanzhou, Lanzhou 730000, PR China.
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12
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Wang X, Wang S, Liu Y, Huang D, Zheng K, Zhang Y, Wang X, Liu Q, Yang D, Wang Y. Comparative effects of SNX-7081 and SNX-2112 on cell cycle, apoptosis and Hsp90 client proteins in human cancer cells. Oncol Rep 2014; 33:230-8. [PMID: 25334086 DOI: 10.3892/or.2014.3552] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 08/01/2014] [Indexed: 11/06/2022] Open
Abstract
SNX-2112, a novel 2-aminobenzamide inhibitor of Hsp90, previously showed a broad spectrum of anticancer activity. However, subsequent development has been discontinued due to ocular toxicity as identified in a phase I study. SNX-7081, another closely related Hsp90 inhibitor with a side chain of indole instead of indazole, has recently attracted attention. The aim of the present study was to investigate the anticancer effects of SNX-7081 in eleven cell lines, as well as the mechanisms involved, with SNX-2112 serving as a reference. The cytotoxic effects were determined using an MTT assay and apoptosis was measured using flow cytometry. The results showed that SNX-7081 exerted better inhibitory effects than SNX-2112 in six eighths of the human cancer cell lines, with an average IC50 of 1 µM. The two inhibitors exerted low cytotoxicity in L-02, HDF and MRC5 normal human cells (IC50 >50 µM), and arrested cancer cells at the G2/M phase in a similar manner to normal cells. Compared with SNX-2112, SNX-7081 exhibited more potent effects on cell apoptosis in four sixths of the human cancer cell lines, and was more active in the downregulation of Hsp90 client proteins. In addition, SNX-7081 exhibited a stronger binding affinity to Hsp90 than SNX-2112 in molecular docking experiments. Considering the superior effects against Hsp90 affinity, cell growth, apoptosis, and Hsp90 client proteins in a majority of human cancer cells, the novel SNX-7081 may be a promising alternative to SNX-2112, which merits further evaluation.
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Affiliation(s)
- Xiao Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Shaoxiang Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Yuting Liu
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Dane Huang
- Guangdong Province Engineering Technology Research Institute of Traditional Chinese Medicine, Guangzhou, Guangdong 510095, P.R. China
| | - Kai Zheng
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Yi Zhang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Xiaoyan Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Qiuying Liu
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
| | - Depo Yang
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Yifei Wang
- Guangzhou Jinan Biomedicine Research and Development Center, National Engineering Research Center of Genetic Medicine, Jinan University, Guangzhou, Guangdong 510632, P.R. China
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13
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Godwin J. The promise of perfect adult tissue repair and regeneration in mammals: Learning from regenerative amphibians and fish. Bioessays 2014; 36:861-71. [DOI: 10.1002/bies.201300144] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- James Godwin
- The Australian Regenerative Medicine Institute (ARMI); Monash University; Clayton Victoria Australia
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14
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Kurosu T, Nagao T, Wu N, Oshikawa G, Miura O. Inhibition of the PI3K/Akt/GSK3 pathway downstream of BCR/ABL, Jak2-V617F, or FLT3-ITD downregulates DNA damage-induced Chk1 activation as well as G2/M arrest and prominently enhances induction of apoptosis. PLoS One 2013; 8:e79478. [PMID: 24260231 PMCID: PMC3832535 DOI: 10.1371/journal.pone.0079478] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 10/01/2013] [Indexed: 11/24/2022] Open
Abstract
Constitutively-activated tyrosine kinase mutants, such as BCR/ABL, FLT3-ITD, and Jak2-V617F, play important roles in pathogenesis of hematopoietic malignancies and in acquisition of therapy resistance. We previously found that hematopoietic cytokines enhance activation of the checkpoint kinase Chk1 in DNA-damaged hematopoietic cells by inactivating GSK3 through the PI3K/Akt signaling pathway to inhibit apoptosis. Here we examine the possibility that the kinase mutants may also protect DNA-damaged cells by enhancing Chk1 activation. In cells expressing BCR/ABL, FLT3-ITD, or Jak2-V617F, etoposide induced a sustained activation of Chk1, thus leading to the G2/M arrest of cells. Inhibition of these kinases by their inhibitors, imatinib, sorafenib, or JakI-1, significantly abbreviated Chk1 activation, and drastically enhanced apoptosis induced by etoposide. The PI3K inhibitor GD-0941 or the Akt inhibitor MK-2206 showed similar effects with imatinib on etoposide-treated BCR/ABL-expressing cells, including those expressing the imatinib-resistant T315I mutant, while expression of the constitutively activated Akt1-myr mutant conferred resistance to the combined treatment of etoposide and imatinib. GSK3 inhibitors, including LiCl and SB216763, restored the sustained Chk1 activation and mitigated apoptosis in cells treated with etoposide and the inhibitors for aberrant kinases, PI3K, or Akt. These observations raise a possilibity that the aberrant kinases BCR/ABL, FLT3-ITD, and Jak2-V617F may prevent apoptosis induced by DNA-damaging chemotherapeutics, at least partly through enhancement of the Chk1-mediated G2/M checkpoint activation, by inactivating GSK3 through the PI3K/Akt signaling pathway. These results shed light on the molecular mechanisms for chemoresistance of hematological malignancies and provide a rationale for the combined treatment with chemotherapy and the tyrosine kinase or PI3K/Akt pathway inhibitors against these diseases.
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Affiliation(s)
- Tetsuya Kurosu
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Toshikage Nagao
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Nan Wu
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Gaku Oshikawa
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Osamu Miura
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- * E-mail:
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15
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Qiu Y, Jiang L, Wang C, Wang Y, Li T, Xing B, Zhou M, Kong T, Dong W. Scorpion venom peptide SPVII promotes irradiated cells proliferation and increases the expression of the IL-3 receptor. Cell Biosci 2013; 3:28. [PMID: 23835458 PMCID: PMC3708784 DOI: 10.1186/2045-3701-3-28] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 06/06/2013] [Indexed: 11/23/2022] Open
Abstract
Background The previous investigation demonstrated the radioprotective efficacy of peptides isolated from the venom of Buthus Martti Karsch. In this study, the effect of isolated scorpion venom peptide II (SVPII) on irradiated M-NFS-60 cells and mouse bone marrow mononuclear cells (BM-MNCs) was observed. The AlamarBlue cell viability assay, a colony-forming unit (CFU) assay, flow cytometry (FCM), immunofluorescence, and Western blotting were used to evaluate cell proliferation, cell cycle progression, and the expression of the IL-3 receptor (IL-3R) protein in non-irradiated and irradiated cells. Results Proliferation of irradiated M-NFS-60 cells was significantly accelerated by SPVII, and this effect was further enhanced by co-application of IL-3. Similarly, SPVII increased the number of BM-MNC CFUs and this proliferative effect was greater in the presence of SVPII plus IL-3. In addition, SPVII significantly altered cell cycle progression; SVPII enhanced the fraction of unirradiated M-NFS-60 cells in S phase and the fraction of irradiated M-NFS-60 cells arrested in G2/M. The expression of IL-3R protein by unirradiated M-NFS-60 cells was enhanced significantly by SVPII, and SVPII-induced IL-3R overexpression was 10-fold greater in irradiated M-NFS-60 cells. Conclusions These results indicated the hematopoietic growth factor (HGF)-like effects of SVPII on irradiated cells, possibly mediated by upregulation of IL-3R.
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Affiliation(s)
- Yifang Qiu
- Department of Pathophysiology, Guangzhou Medical College, Guangzhou 510182, Guangdong, China.
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16
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Chen B, Duan L, Yin G, Tan J, Jiang X. Simultaneously expressed miR-424 and miR-381 synergistically suppress the proliferation and survival of renal cancer cells---Cdc2 activity is up-regulated by targeting WEE1. Clinics (Sao Paulo) 2013; 68:825-33. [PMID: 23778472 PMCID: PMC3674285 DOI: 10.6061/clinics/2013(06)17] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Accepted: 02/26/2013] [Indexed: 01/05/2023] Open
Abstract
OBJECTIVES MiRNAs are intrinsic RNAs that interfere with protein translation. Few studies on the synergistic effects of miRNAs have been reported. Both miR-424 and miR-381 have been individually reported to be involved in carcinogenesis. They share a common putative target, WEE1, which is described as an inhibitor of G2/M progression. Here, we studied the synergistic effects of miR-424 and miR-381 on renal cancer cells. METHODS The viability of 786-O cells was analyzed after transfection with either a combination of miR-424 and miR-381 or each miRNA alone. We investigated cell cycle progression and apoptosis with flow cytometry. To confirm apoptosis and the abrogation of G2/M arrest, we determined the level of pHH3, which is an indicator of mitosis, and caspase-3/7 activity. The expression levels of WEE1, Cdc25, γH2AX, and Cdc2 were manipulated to investigate the roles of these proteins in the miRNA-induced anti-tumor effects. To verify that WEE1 was a direct target of both miR-424 and miR-381, we performed a dual luciferase reporter assay. RESULTS We showed that the combination of these miRNAs synergistically inhibited proliferation, abrogated G2/M arrest, and induced apoptosis. This combination led to Cdc2 activation through WEE1 inhibition. This regulation was more effective when cells were treated with both miRNAs than with either miRNA alone, indicating synergy between these miRNAs. WEE1 was verified to be a direct target of each miRNA according to the luciferase reporter assay. CONCLUSIONS These data clearly demonstrate that these two miRNAs might synergistically act as novel modulators of tumorigenesis by down-regulating WEE1 expression in renal cell cancer cells.
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Affiliation(s)
- Binghai Chen
- Third Xiang-Ya Hospital of Central South University, Department of Urology, Changsha, Hunan/China
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17
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Kolb RH, Greer PM, Cao PT, Cowan KH, Yan Y. ERK1/2 signaling plays an important role in topoisomerase II poison-induced G2/M checkpoint activation. PLoS One 2012; 7:e50281. [PMID: 23166842 PMCID: PMC3500378 DOI: 10.1371/journal.pone.0050281] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Accepted: 10/23/2012] [Indexed: 11/29/2022] Open
Abstract
Topo II poisons, which target topoisomerase II (topo II) to generate enzyme mediated DNA damage, have been commonly used for anti-cancer treatment. While clinical evidence demonstrate a capability of topo II poisons in inducing apoptosis in cancer cells, accumulating evidence also show that topo II poison treatment frequently results in cell cycle arrest in cancer cells, which was associated with subsequent resistance to these treatments. Results in this report indicate that treatment of MCF-7 and T47D breast cancer cells with topo II poisons resulted in an increased phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and an subsequent induction of G2/M cell cycle arrest. Furthermore, inhibition of ERK1/2 activation using specific inhibitors markedly attenuated the topo II poison-induced G2/M arrest and diminished the topo II poison-induced activation of ATR and Chk1 kinases. Moreover, decreased expression of ATR by specific shRNA diminished topo II poison-induced G2/M arrest but had no effect on topo II poison-induced ERK1/2 activation. In contrast, inhibition of ERK1/2 signaling had little, if any, effect on topo II poison-induced ATM activation. In addition, ATM inhibition by either incubation of cells with ATM specific inhibitor or transfection of cells with ATM specific siRNA did not block topo II poison-induced G2/M arrest. Ultimately, inhibition of ERK1/2 signaling greatly enhanced topo II poison-induced apoptosis. These results implicate a critical role for ERK1/2 signaling in the activation of G2/M checkpoint response following topo II poison treatment, which protects cells from topo II poison-induced apoptosis.
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Affiliation(s)
- Ryan H. Kolb
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Patrick M. Greer
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Phu T. Cao
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Kenneth H. Cowan
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
| | - Ying Yan
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska, United States of America
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Nagao T, Oshikawa G, Wu N, Kurosu T, Miura O. DNA damage stress and inhibition of Jak2-V617F cause its degradation and synergistically induce apoptosis through activation of GSK3β. PLoS One 2011; 6:e27397. [PMID: 22087308 PMCID: PMC3210803 DOI: 10.1371/journal.pone.0027397] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 10/16/2011] [Indexed: 11/19/2022] Open
Abstract
The cytoplasmic tyrosine kinase Jak2 plays a crucial role in cytokine receptor signaling in hematopoietic cells. The activated Jak2-V617F mutant is present in most cases of BCR/ABL-negative myeloproliferative neoplasms and constitutively activates downstream signals from homodimeric cytokine receptors, such as the erythropoietin receptor (EpoR). Here we examine the effects of DNA damage stress on Jak2 or Jak2-V617F and on induction of apoptosis in hematopoietic cells. Etoposide or doxorubicin dose-dependently decreased the expression level of Jak2 in UT7 or 32D cells expressing EpoR in the absence of Epo and that of exogenously expressed Jak2-V617F in UT7 cells when cotreated with the Jak2 inhibitor JakI-1 or AG490. Studies with pharmacological inhibitors and genetic manipulations further showed that downregulation of the PI3K/Akt pathway leading to the activation of GSK3β may be involved in downregulation of Jak2 or Jak2-V617F as well as in synergistic induction of Bax activation and apoptosis. The downregulation of Jak2 was inhibited by the proteasome inhibitor MG132 or by expression of both of loss-of-function mutants of c-Cbl and Cbl-b, E3 ubiquitin ligases which facilitated ubiquitination of Jak2-V617F when co-expressed in 293T cells. The pan-caspase inhibitor Boc-d-fmk also inhibited the Jak2 downregulation as well as appearance of a 100-kDa fragment that contained the N-terminal portion of Jak2 in response to DNA damage. Together, these data suggest that DNA damage stress with simultaneous inhibition of the kinase activity causes degradation of Jak2 or Jak2-V617F by caspase cleavage and proteasomal degradation through GSK3β activation, which is closely involved in synergistic induction of apoptosis in hematopoietic cells.
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Affiliation(s)
- Toshikage Nagao
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Gaku Oshikawa
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Nan Wu
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuya Kurosu
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Osamu Miura
- Department of Hematology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- * E-mail:
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Cancer-associated adipocytes promotes breast tumor radioresistance. Biochem Biophys Res Commun 2011; 411:102-6. [PMID: 21712027 DOI: 10.1016/j.bbrc.2011.06.101] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Accepted: 06/11/2011] [Indexed: 12/29/2022]
Abstract
Mature adipocytes are excellent candidates to influence tumor behavior through heterotypic signaling processes since these cells produce hormones, growth factors, cytokines and other molecules, a heterogeneous group of molecules named adipokines. Using a 2D coculture system, we demonstrate that breast tumor cells previously co-cultivated with mature adipocytes exhibit radioresistance and an earlier and higher increase in the effector kinase Chk1, a phenotype that was associated with decreased cell death as compared to tumor cells grown alone. Interestingly, the adipocytes-induced tumor changes taking place during the coculture time preceding the exposure to IR were sufficient to confer the radioresistant effect. Notorious among the changes brought by adipocytes was the significant increase of IL-6 expression in tumor cells, whose activity may well account for the observed tumor cell protection from IR toxicity. Indeed, our data confirmed the protective role of this cytokine as tumor cells incubated after irradiation with recombinant IL-6 exhibit an increased in Chk1 phosphorylation and a radioresistant phenotype, thus far recapitulating the effects observed in the presence of adipocytes. Our current study sheds light on a new role of tumor-surrounding adipocytes in fostering a radioresistant phenotype in breast tumors, a finding that might have important clinical implications in obese patients that frequently exhibit aggressive diseases.
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Sakaue-Sawano A, Kobayashi T, Ohtawa K, Miyawaki A. Drug-induced cell cycle modulation leading to cell-cycle arrest, nuclear mis-segregation, or endoreplication. BMC Cell Biol 2011; 12:2. [PMID: 21226962 PMCID: PMC3277280 DOI: 10.1186/1471-2121-12-2] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2010] [Accepted: 01/13/2011] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Cancer cell responses to chemotherapeutic agents vary, and this may reflect different defects in DNA repair, cell-cycle checkpoints, and apoptosis control. Cytometry analysis only quantifies dye-incorporation to examine DNA content and does not reflect the biological complexity of the cell cycle in drug discovery screens. RESULTS Using population and time-lapse imaging analyses of cultured immortalized cells expressing a new version of the fluorescent cell-cycle indicator, Fucci (Fluorescent Ubiquitination-based Cell Cycle Indicator), we found great diversity in the cell-cycle alterations induced by two anticancer drugs. When treated with etoposide, an inhibitor of DNA topoisomerase II, HeLa and NMuMG cells halted at the G2/M checkpoint. HeLa cells remained there, but NMuMG cells then overrode the checkpoint and underwent nuclear mis-segregation or avoided the checkpoint and entered the endoreplication cycle in a drug concentration dependent manner. In contrast, an inhibitor of Cdk4 led to G1 arrest or endoreplication in NMuMG cells depending upon the initial cell-cycle phase of drug exposure. CONCLUSIONS Drug-induced cell cycle modulation varied not only between different cell types or following treatment with different drugs, but also between cells treated with different concentrations of the same drug or following drug addition during different phases of the cell cycle. By combining cytometry analysis with the Fucci probe, we have developed a novel assay that fully integrates the complexity of cell cycle regulation into drug discovery screens. This assay system will represent a powerful drug-discovery tool for the development of the next generation of anti-cancer therapies.
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Affiliation(s)
- Asako Sakaue-Sawano
- Life Function and Dynamics, ERATO, JST, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
- Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
| | - Tamiyo Kobayashi
- MIS Division, Olympus Corp., 2-3 Kuboyama-cho, Hachioji, Tokyo 192-8512, Japan
| | - Kenji Ohtawa
- Brain Science Research Division, Brain Science and Life Technology, Research Foundation, 1-28-12 Narimasu, Itabashi, Tokyo 175-0094, Japan
| | - Atsushi Miyawaki
- Life Function and Dynamics, ERATO, JST, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
- Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
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Wang M, Gao M, Miller KD, Sledge GW, Hutchins GD, Zheng QH. The first synthesis of [(11)C]SB-216763, a new potential PET agent for imaging of glycogen synthase kinase-3 (GSK-3). Bioorg Med Chem Lett 2010; 21:245-9. [PMID: 21115250 DOI: 10.1016/j.bmcl.2010.11.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Accepted: 11/03/2010] [Indexed: 11/19/2022]
Abstract
SB-216763 is a novel, potent and selective glycogen synthase kinase-3 (GSK-3) inhibitor with an IC(50) value of 34 nM. [(11)C]SB-216763 (3-(2,4-dichlorophenyl)-4-(1-[(11)C]methyl-1H-indol-3-yl)-1H-pyrrole-2,5-dione), a new potential PET agent for imaging of GSK-3, was first designed and synthesized in 20-30% decay corrected radiochemical yield and 370-555 GBq/μmol specific activity at end of bombardment (EOB). The synthetic strategy was to prepare a carbon-11-labeled maleic anhydride intermediate followed by the conversion to maleimide.
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Affiliation(s)
- Min Wang
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16th Street, Room 202, Indianapolis, IN 46202, USA
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22
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The protein phosphatase 1 regulator PNUTS is a new component of the DNA damage response. EMBO Rep 2010; 11:868-75. [PMID: 20890310 DOI: 10.1038/embor.2010.134] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 08/09/2010] [Accepted: 08/11/2010] [Indexed: 12/17/2022] Open
Abstract
The function of protein phosphatase 1 nuclear-targeting subunit (PNUTS)--one of the most abundant nuclear-targeting subunits of protein phosphatase 1 (PP1c)--remains largely uncharacterized. We show that PNUTS depletion by small interfering RNA activates a G2 checkpoint in unperturbed cells and prolongs G2 checkpoint and Chk1 activation after ionizing-radiation-induced DNA damage. Overexpression of PNUTS-enhanced green fluorescent protein (EGFP)--which is rapidly and transiently recruited at DNA damage sites--inhibits G2 arrest. Finally, γH2AX, p53-binding protein 1, replication protein A and Rad51 foci are present for a prolonged period and clonogenic survival is decreased in PNUTS-depleted cells after ionizing radiation treatment. We identify the PP1c regulatory subunit PNUTS as a new and integral component of the DNA damage response involved in DNA repair.
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Xia S, Yu S, Fu Q, Liu F, Zheng W, Fu X, Zhao Y. Inhibiting PI3K/Akt pathway increases DNA damage of cervical carcinoma HeLa cells by drug radiosensitization. ACTA ACUST UNITED AC 2010; 30:360-4. [PMID: 20556582 DOI: 10.1007/s11596-010-0357-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Indexed: 01/14/2023]
Abstract
This study examined the role of PI3K/Akt pathway in radiosensitization of DNA damage of cervical carcinoma cells. The 50% inhibition concentration (IC50) of cisplatin and docetaxel in HeLa cells was detected by Mono-nuclear cell direct cytotoxicity assay (MTT) in vitro. HeLa cells were treated by cisplatin/docetaxel of 10 percent of IC20 alone or combined with LY294002 for 24 h, and then radiated by different doses of X-ray. The cell survival ratio was obtained by means of clone formation. One-hit multi-target model was fitted to the cell survival curve to calculate dose quasithreshold (Dq), mean lethal dose (D0), 2Gy survival fraction (SF2) and sensitization enhancement ratio (SER). The pAkt and total Akt expression was detected by Western blotting and DNA damage by neutro-comet electrophoresis. The HeLa cells were randomly divided into 7 groups in terms of different treatments: Control; radiation treatment (RT) group; LY294002+RT group; cisplatin+RT group; docetaxel+RT group; LY294002+cisplatin+RT group; LY294002+docetaxel+RT group. The apoptosis ratio of each group was measured by flow cytometry. The results showed that docetaxel and cisplatin significantly enhanced the phosphorylation of Akt in radiation-treated HeLa cells. The Dq, D0 and SF2 in LY294002-contained groups were lower than those in docetaxel or cisplatin+RT group. The SER in the LY294002+docetaxel+RT group was 1.35 times that of the docetaxel+RT group, and that in the LY294002+cisplatin+RT group 1.26 times that of the cisplatin+RT group. The Comet electrophoresis showed that tail distance in the LY294002+cisplatin+RT group or LY294002+docetaxel+ RT group was longer than in the cisplatin+RT group or docetaxel+RT group. The apoptosis ratio in the LY294002+cisplatin+RT group or LY294002+docetaxel +RT group was higher than in the cisplatin+RT group or docetaxel+RT group. It was concluded that inhibiting PI3K/Akt pathway can increase the effect of docetaxel and cisplatin on the radiosensitivity of HeLa cells and DNA damage resulted from radiation.
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Affiliation(s)
- Shu Xia
- Department of Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Soule BP, Simone NL, DeGraff WG, Choudhuri R, Cook JA, Mitchell JB. Loratadine dysregulates cell cycle progression and enhances the effect of radiation in human tumor cell lines. Radiat Oncol 2010; 5:8. [PMID: 20128919 PMCID: PMC2829588 DOI: 10.1186/1748-717x-5-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Accepted: 02/03/2010] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND The histamine receptor-1 (H1)-antagonist, loratadine has been shown to inhibit growth of human colon cancer xenografts in part due to cell cycle arrest in G2/M. Since this is a radiation sensitive phase of the cell cycle, we sought to determine if loratadine modifies radiosensitivity in several human tumor cell lines with emphasis on human colon carcinoma (HT29). METHODS Cells were treated with several doses of loratadine at several time points before and after exposure to radiation. Radiation dose modifying factors (DMF) were determined using full radiation dose response survival curves. Cell cycle phase was determined by flow cytometry and the expression of the cell cycle-associated proteins Chk1, pChk1(ser345), and Cyclin B was analyzed by western blot. RESULTS Loratadine pre-treatment of exponentially growing cells (75 microM, 24 hours) increased radiation-induced cytotoxicity yielding a radiation DMF of 1.95. However, treatment of plateau phase cells also yielded a DMF of 1.3 suggesting that mechanisms other than cell cycle arrest also contribute to loratadine-mediated radiation modification. Like irradiation, loratadine initially induced G2/M arrest and activation of the cell-cycle associated protein Chk1 to pChk1(ser345), however a subsequent decrease in expression of total Chk1 and Cyclin B correlated with abrogation of the G2/M checkpoint. Analysis of DNA repair enzyme expression and DNA fragmentation revealed a distinct pattern of DNA damage in loratadine-treated cells in addition to enhanced radiation-induced damage. Taken together, these data suggest that the observed effects of loratadine are multifactorial in that loratadine 1) directly damages DNA, 2) activates Chk1 thereby promoting G2/M arrest making cells more susceptible to radiation-induced DNA damage and, 3) downregulates total Chk1 and Cyclin B abrogating the radiation-induced G2/M checkpoint and allowing cells to re-enter the cell cycle despite the persistence of damaged DNA. CONCLUSIONS Given this unique possible mechanism of action, loratadine has potential as a chemotherapeutic agent and as a modifier of radiation responsiveness in the treatment of cancer and, as such, may warrant further clinical evaluation.
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Affiliation(s)
- Benjamin P Soule
- Radiation Biology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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25
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Merry C, Fu K, Wang J, Yeh IJ, Zhang Y. Targeting the checkpoint kinase Chk1 in cancer therapy. Cell Cycle 2010; 9:279-83. [PMID: 20023404 DOI: 10.4161/cc.9.2.10445] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
A paramount objective of the eukaryotic cell division cycle is to overcome numerous internal and external insults to faithfully duplicate the genetic information once per every cycle. This is carried out by elaborate networks of genome surveillance signaling pathways, termed replication checkpoints. Central to replication checkpoints are two protein kinases, the upstream kinase ATR, and its downstream target kinase, Chk1. When the DNA replication process is interrupted, the ATR-Chk1 pathway transmits signals to delay cell cycle progression, and to maintain fork viability so that DNA duplication can resume after the initial damage is corrected. Previous studies showed that replicative stress not only activated Chk1, but also triggered the ubiquitin-dependent destruction of Chk1 in cultured human cells. In a recent study, we identified the F-box protein, Fbx6, as the mediator that regulates Chk1 ubiquitination and degradation in both normally cycling cells and during replication stress. We further showed that expression levels of Chk1 and Fbx6 exhibited an overall inverse correlation in both cultured cancer cell lines and in breast tumor tissues, and that defects in Chk1 degradation, for instance, due to reduced expression of Fbx6, rendered tumor cells resistant to anticancer treatment. Here we highlight those findings and their implications in the replication checkpoint and cellular sensitivity to cancer therapies.
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Affiliation(s)
- Callie Merry
- Department of Pharmacology, Case Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
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26
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Lei H, Quelle FW. FOXO transcription factors enforce cell cycle checkpoints and promote survival of hematopoietic cells after DNA damage. Mol Cancer Res 2009; 7:1294-303. [PMID: 19671690 DOI: 10.1158/1541-7786.mcr-08-0531] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The PI3K/AKT signaling pathway contributes to cell cycle progression of cytokine-dependent hematopoietic cells under normal conditions, and it is absolutely required to override DNA damage-induced cell cycle arrest checkpoints in these cells. Phosphatidylinositol-3-kinase (PI3K)/AKT activity also correlates with Cdk2 activity in hematopoietic cells, suggesting that Cdk2 activation may be a relevant end point for this signaling pathway. However, mediators downstream of AKT in this pathway have not been defined. The forkhead transcription factor O (FOXO) family are negatively regulated by AKT-dependent phosphorylation and are known regulators of genes affecting cell cycle progression. We show that enhanced FOXO activity replicates the effect of PI3K inhibitors in enforcing G(1) and G(2) phase arrest after DNA damage. Conversely, knockdown of endogenous FOXO proteins increased Cdk2 activity and overrode DNA damage checkpoints in cells lacking PI3K activity. Moreover, loss of FOXO activity caused an increase in sensitivity to cisplatin-induced cell death, which was associated with failure to arrest cell cycle progression in the face of DNA damage caused by this chemotherapeutic agent. These cell cycle arrests were dependent on p27 expression when mediated by FOXO3a alone, but also involve p27-independent mechanisms when promoted by endogenous FOXO proteins. Together, these observations show that FOXO proteins enforce DNA damage-induced cell cycle arrest in hematopoietic cells. Inhibition of FOXO activity by cytokine-induced PI3K/AKT signaling is sufficient to override these DNA damage-induced cell cycle checkpoints, but may negatively impact hematopoietic cell viability.
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Affiliation(s)
- Hong Lei
- Department of Pharmacology, The University of Iowa, Carver College of Medicine, Iowa City, IA 52242, USA
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27
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Glycogen synthase kinase-3β regulates etoposide-induced apoptosis via Bcl-2 mediated caspase-3 activation in C3H10T1/2 cells. Apoptosis 2009; 14:771-7. [DOI: 10.1007/s10495-009-0348-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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28
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Yun SI, Yoon HY, Jeong SY, Chung YS. Glucocorticoid induces apoptosis of osteoblast cells through the activation of glycogen synthase kinase 3beta. J Bone Miner Metab 2009; 27:140-8. [PMID: 19066717 DOI: 10.1007/s00774-008-0019-5] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Accepted: 05/18/2008] [Indexed: 12/31/2022]
Abstract
Glucocorticoids (GCs), which play an important role in the normal regulation of bone remodeling, are widely used as anti-inflammatory and chemotherapeutic agents. However, continued exposure to GCs results in osteoporosis, which is partially due to apoptosis of osteoblasts and osteocytes. To understand the mechanism of how GCs induce cell death in osteoblasts, we examined apoptotic effects of dexamethasone (Dex), GC, on MC3T3-E1 osteoblast cells. Results revealed that Dex-induced apoptosis was inhibited by a GC receptor antagonist, mifepristone, and a general caspase inhibitor, Z-VAD-fmk, indicating that Dex induces apoptosis of MC3T3-E1 cells through the pathways involved in GC receptor and caspase. Glycogen synthase kinase 3beta (GSK3beta) is known to participate in apoptosis signaling in MC3T3-E1 cells. Dex activated both GSK3beta and p38-mitogen-activated protein kinase (MAPK). The inhibition of GSK3beta by inhibitor (LiCl) or small interference RNA (siRNA) decreased apoptosis. In contrast, the inhibition of p38-MAPK by inhibitor (SB203580) or siRNA did not decrease, but increase apoptosis. These results suggest that Dex-mediated apoptosis of osteoblasts is facilitated by GSK3beta, but prevented by p38-MAPK.
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Affiliation(s)
- Sun-Il Yun
- Department of Endocrinology and Metabolism, Ajou University School of Medicine, San 5 Wonchon-Dong Yeongtong-Gu, Suwon City, Gyeonggi Province 443-721, South Korea
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29
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Jamil S, Mojtabavi S, Hojabrpour P, Cheah S, Duronio V. An essential role for MCL-1 in ATR-mediated CHK1 phosphorylation. Mol Biol Cell 2008; 19:3212-20. [PMID: 18495871 DOI: 10.1091/mbc.e07-11-1171] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Here we report a novel role for myeloid cell leukemia 1 (Mcl-1), a Bcl-2 family member, in regulating phosphorylation and activation of DNA damage checkpoint kinase, Chk1. Increased expression of nuclear Mcl-1 and/or a previously reported short nuclear form of Mcl-1, snMcl-1, was observed in response to treatment with low concentrations of etoposide or low doses of UV irradiation. We showed that after etoposide treatment, Mcl-1 could coimmunoprecipitate with the regulatory kinase, Chk1. Chk1 is a known regulator of DNA damage response, and its phosphorylation is associated with activation of the kinase. Transient transfection with Mcl-1 resulted in an increase in the expression of phospho-Ser345 Chk1, in the absence of any evidence of DNA damage, and accumulation of cells in G2. Importantly, knockdown of Mcl-1 expression abolished Chk1 phosphorylation in response to DNA damage. Mcl-1 could induce Chk1 phosphorylation in ATM-negative (ataxia telangectasia mutated) cells, but this response was lost in ATR (AT mutated and Rad3 related)-defective cells. Low levels of UV treatment also caused transient increases in Mcl-1 levels and an ATR-dependent phosphorylation of Chk1. Together, our results strongly support an essential regulatory role for Mcl-1, perhaps acting as an adaptor protein, in controlling the ATR-mediated regulation of Chk1 phosphorylation.
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Affiliation(s)
- Sarwat Jamil
- Department of Medicine, University of British Columbia and Vancouver Coastal Health Research Institute, Vancouver, BC, V6H 3Z6 Canada
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30
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Wang Q, Zhou Y, Wang X, Evers BM. p27 Kip1 nuclear localization and cyclin-dependent kinase inhibitory activity are regulated by glycogen synthase kinase-3 in human colon cancer cells. Cell Death Differ 2008; 15:908-19. [PMID: 18408738 DOI: 10.1038/cdd.2008.2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The cellular mechanisms regulating intestinal differentiation are poorly understood. Sodium butyrate (NaBT), a short-chain fatty acid, increases p27 Kip1 expression and induces cell cycle arrest associated with intestinal cell differentiation. Here, we show that treatment of intestinal-derived cells with NaBT induced G0/G1 arrest and intestinal alkaline phosphatase, a marker of differentiation, activity and mRNA expression; this induction was attenuated by inhibition of glycogen synthase kinase-3 (GSK-3). Moreover, treatment with NaBT increased the nuclear, but not the cytosolic, expression and activity of GSK-3beta. NaBT decreased cyclin-dependent kinase CDK2 activity and induced p27 Kip1 expression; inhibition of GSK-3 rescued NaBT-inhibited CDK2 activity and blocked NaBT-induced p27 Kip1 expression in the nucleus but not in the cytoplasm. In addition, we demonstrate that NaBT decreased the expression of S-phase kinase-associated protein 2 (Skp2), and this decrease was attenuated by GSK-3 inhibition. Furthermore, NaBT increased p27 Kip1 binding to CDK2, which was completely abolished by GSK-3 inhibition. Overexpression of an active form of GSK-3beta reduced Skp2 expression, increased p27 Kip1 in the nucleus and increased p27 Kip1 binding to CDK2. Our results suggest that GSK-3 not only regulates nuclear p27 Kip1 expression through the downregulation of nuclear Skp2 expression but also functions to regulate p27 Kip1 assembly with CDK2, thereby playing a critical role in the G0/G1 arrest associated with intestinal cell differentiation.
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Affiliation(s)
- Q Wang
- Department of Surgery, The University of Texas Medical Branch, Galveston, TX 77555-0536, USA
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31
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Li Z, Thiele CJ. Targeting Akt to increase the sensitivity of neuroblastoma to chemotherapy: lessons learned from the brain-derived neurotrophic factor/TrkB signal transduction pathway. Expert Opin Ther Targets 2008; 11:1611-21. [PMID: 18020981 DOI: 10.1517/14728222.11.12.1611] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neuroblastoma (NB) is a neural crest precursor cell-derived extracranial solid tumor in children. Patients with a poor prognosis are often resistant to chemotherapy and have tumors that express the neuronal growth/survival factor brain-derived neurotrophic factor and its tyrosine kinase receptor, TrkB. In this article, the authors discuss a growth/survival factor-stimulated mechanism leading to chemoresistance in NB that is mediated by the PI3K/Akt signaling pathway. Besides brain-derived neurotrophic factor/TrkB, other growth/survival factors and their receptors also activate the PI3K/Akt pathway and have the potential to mediate chemoresistance in NB. These findings raise the possibility of a new therapeutic approach in NB that would target Akt, the common downstream mediator of multiple growth/survival factor signaling pathways, to enhance the efficacy of chemotherapeutics. Several classes of Akt inhibitors, including phosphatidylinositol ether lipid analogs, alkylphospholipid analogs, allosteric Akt kinase inhibitors, HSP90 inhibitor and HIV protease inhibitors are discussed.
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Affiliation(s)
- Zhijie Li
- Cell & Molecular Biology Section, Paediatric Oncology Branch National Cancer Institute, National Institutes of Health, 10 Center Drive, Building 10/CRC, Room 1-5816, Bethesda, MD 20892, USA
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32
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Konstantinova IM, Tsimokha AS, Mittenberg AG. Role of proteasomes in cellular regulation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2008; 267:59-124. [PMID: 18544497 DOI: 10.1016/s1937-6448(08)00602-3] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The 26S proteasome is the key enzyme of the ubiquitin-dependent pathway of protein degradation. This energy-dependent nanomachine is composed of a 20S catalytic core and associated regulatory complexes. The eukaryotic 20S proteasomes demonstrate besides several kinds of peptidase activities, the endoribonuclease, protein-chaperone and DNA-helicase activities. Ubiquitin-proteasome pathway controls the levels of the key regulatory proteins in the cell and thus is essential for life and is involved in regulation of crucial cellular processes. Proteasome population in the cell is structurally and functionally heterogeneous. These complexes are subjected to tightly organized regulation, particularly, to a variety of posttranslational modifications. In this review we will summarize the current state of knowledge regarding proteasome participation in the control of cell cycle, apoptosis, differentiation, modulation of immune responses, reprogramming of these particles during these processes, their heterogeneity and involvement in the main levels of gene expression.
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33
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Wang X, Sun H, Li C. Nitric oxide induces promyelocytic cell growth arrest and apoptosis through deactivation of Akt pathway. Leuk Res 2006; 31:653-60. [PMID: 16950511 DOI: 10.1016/j.leukres.2006.07.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2006] [Revised: 07/29/2006] [Accepted: 07/30/2006] [Indexed: 11/20/2022]
Abstract
It is NO that mediates the inhibitory effect of IFN-gamma, MIP-1alpha and TNFalpha on hematopoiesis. However, the mechanism for NO effect on the hematopoietic system is likely to not clear. In the current work, we demonstrates that NO can directly suppress the colony formation of granulocyte/macrophage in vitro. Using a granulocyte/macrophage progenitor (GMP) model, HL-60 cell line, we show that NO inhibits the proliferation of HL-60 cells by inducing G0/G1 arrest and apoptosis in a dose- and time-dependent manner. Exposure of HL-60 cells to 1mM SNP for 2-48h results in marked decrease in Akt activation and Bad phosphorylation. Constitutively active Akt overexpression reduces NO-induced apoptosis and cell cycle arrest in HL-60 cells. A further investigation on apoptosis related protein shows that NO induces Bid cleavage and Bax expression but down-regulates the expression of Bcl-2 and Bcl-xL. We also demonstrate here that G0/G1 arrest is resulted from NO-induced disruption of cell cycle balance, which is mediated by up-regulation of p21(waf/cip1), p27(kip1) and down-regulation of cyclin D1, cyclin E. In brief, NO-induced apoptosis and G0/G1 arrest is mediated through regulation of apoptosis and cell cycle related protein, which may depend on Akt deactivation by NO, ultimately led to its inhibitory effect on hematopoiesis.
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Affiliation(s)
- Xiaojian Wang
- Institute of Immunology, Tsinghua University School of Medicine, Beijing 100084, PR China.
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34
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Beurel E, Jope RS. The paradoxical pro- and anti-apoptotic actions of GSK3 in the intrinsic and extrinsic apoptosis signaling pathways. Prog Neurobiol 2006; 79:173-89. [PMID: 16935409 PMCID: PMC1618798 DOI: 10.1016/j.pneurobio.2006.07.006] [Citation(s) in RCA: 444] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Revised: 07/14/2006] [Accepted: 07/17/2006] [Indexed: 12/21/2022]
Abstract
Few things can be considered to be more important to a cell than its threshold for apoptotic cell death, which can be modulated up or down, but rarely in both directions, by a single enzyme. Therefore, it came as quite a surprise to find that one enzyme, glycogen synthase kinase-3 (GSK3), has the perplexing capacity to either increase or decrease the apoptotic threshold. These apparently paradoxical effects now are known to be due to GSK3 oppositely regulating the two major apoptotic signaling pathways. GSK3 promotes cell death caused by the mitochondrial intrinsic apoptotic pathway, but inhibits the death receptor-mediated extrinsic apoptotic signaling pathway. Intrinsic apoptotic signaling, activated by cell damage, is promoted by GSK3 by facilitation of signals that cause disruption of mitochondria and by regulation of transcription factors that control the expression of anti- or pro-apoptotic proteins. The extrinsic apoptotic pathway entails extracellular ligands stimulating cell-surface death receptors that initiate apoptosis by activating caspase-8, and this early step in extrinsic apoptotic signaling is inhibited by GSK3. Thus, GSK3 modulates key steps in each of the two major pathways of apoptosis, but in opposite directions. Consequently, inhibitors of GSK3 provide protection from intrinsic apoptosis signaling but potentiate extrinsic apoptosis signaling. Studies of this eccentric ability of GSK3 to oppositely influence two types of apoptotic signaling have shed light on important regulatory mechanisms in apoptosis and provide the foundation for designing the rational use of GSK3 inhibitors for therapeutic interventions.
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Affiliation(s)
- Eléonore Beurel
- Department of Psychiatry and Behavioral Neurobiology, Sparks Center 1057, University of Alabama at Birmingham, Birmingham, AL 35294-0017, USA
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35
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Chen JS, Lin SY, Tso WL, Yeh GC, Lee WS, Tseng H, Chen LC, Ho YS. Checkpoint kinase 1-mediated phosphorylation of Cdc25C and bad proteins are involved in antitumor effects of loratadine-induced G2/M phase cell-cycle arrest and apoptosis. Mol Carcinog 2006; 45:461-78. [PMID: 16649252 DOI: 10.1002/mc.20165] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
In this study, we first demonstrated that loratadine (LOR), a promising world widely used oral anti-histamine, effectively inhibits growth of tumors derived from human colon cancer cells (COLO 205) in an in vivo setting. In vitro study demonstrated that the anti-tumor effects of LOR in COLO 205 cells were mediated by causing G(2)/M phase cell growth cycle arrest and caspase 9-mediated apoptosis. Cell-cycle arrest induced by LOR (75 microM, 24 h) was associated with a significant decrease in protein levels of cyclin B1, cell division cycle (Cdc) 25B, and Cdc25C, leading to accumulation of Tyr-15-phosphorylated Cdc2 (inactive form). Interestingly, LOR (75 microM, for 4 h) treatment also resulted in a rapid and sustained phosphorylation of Cdc25C at Ser-216, leading to its translocation from the nucleus to the cytoplasm because of increased binding with 14-3-3. We further demonstrated that the LOR-induced Cdc25C (Ser-216) phosphorylation was blocked in the presence of checkpoint kinase 1 (Chk1) specific inhibitor (SB-218078). The cells treated with LOR in the presence of Chk1 specific inhibitor (SB-218078) were then released from G(2)/M arrest into apoptosis. These results implied that Chk1-mediated phosphorylation of Cdc25C plays a major role in response to LOR-mediated G(2)/M arrest. Although the Chk1-mediated cell growth arrest in response to DNA damage is well documented, our results presented in this study was the first report to describe the Chk1-mediated G(2)/M cell-cycle arrest by the histamine H1 antagonist, LOR.
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Affiliation(s)
- Jinn-Shiun Chen
- Department of Surgery, Division of Colon and Rectal Surgery, Chang Gung Memorial Hospital, Linkou, Taiwan
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36
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Kurosu T, Takahashi Y, Fukuda T, Koyama T, Miki T, Miura O. p38 MAP kinase plays a role in G2 checkpoint activation and inhibits apoptosis of human B cell lymphoma cells treated with etoposide. Apoptosis 2006; 10:1111-20. [PMID: 16151644 DOI: 10.1007/s10495-005-3372-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
p38 MAPK is mainly activated by stress stimuli and mediates signals that regulate various cellular responses, including cell-cycle progression and apoptosis, depending on cell types and stimuli. Here we examine the role of p38 in regulation of apoptosis and cell cycle checkpoint in Daudi B-cell lymphoma cells treated with the topoisomerase II inhibitor etoposide. Etoposide activated p38, inhibited the G2/M transition with the persistent inhibitory phosphorylation of Cdc2 on Tyr15, and caused apoptosis of Daudi cells. Inducible expression of a dominant negative p38alpha mutant in Daudi cells reduced the inhibition of Cdc2 as well as G2/M arrest and augmented apoptosis induced by etoposide. SB203580, a specific inhibitor of p38alpha and p38beta, similarly reduced the inhibitory phosphorylation of Cdc2 as well as G2/M arrest and augmented apoptosis of Daudi cells treated with etoposide. These results suggest that p38 plays a role in G2/M checkpoint activation through induction of the persistent inhibitory phosphorylation of Cdc2 and, thereby, inhibits apoptosis of Daudi cells treated with etoposide. The present study, thus, raises the possibility that p38 may represent a new target for sensitization of lymphoma cells to DNA-damaging chemotherapeutic agents.
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Affiliation(s)
- T Kurosu
- Department of Hematology, Tokyo Medical and Dental University, 1-5-45 Yushima, Tokyo 113-8519, Bunkyoku, Japan
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Hemström TH, Sandström M, Zhivotovsky B. Inhibitors of the PI3-kinase/Akt pathway induce mitotic catastrophe in non-small cell lung cancer cells. Int J Cancer 2006; 119:1028-38. [PMID: 16570272 DOI: 10.1002/ijc.21927] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Non-small cell lung cancer cells (NSCLC) are more resistant to anticancer treatment as compared with other types of cancer cells. Recently (Hemström et al., Exp Cell Res 2005;305:200-13) we showed that apoptosis of U1810 NSCLC cells induced by the staurosporine analog PKC 412 correlated with inhibition of Akt and ERK1/2, suggesting the involvement of these kinases in cell survival. Here we investigated the contribution of the PI3-kinase/Akt and MEK/ERK pathways to survival of NSCLC cells. The two signaling pathways were studied by using different combinations of the PI3-kinase inhibitors LY-294002 and wortmannin, the Akt activator Ro 31-8220, the MEK inhibitor PD 98059 and PKC 412. PI3-kinase inhibitors induced apoptosis-like death in U1810 cells. H157 cells in general were relatively resistant to PI3 kinase/Akt inhibitors yet these compounds sensitized cells to the DNA-damaging drug VP-16, while Ro 31-8220 could not. PD 98059 only had a sensitizing effect on H157 cells when combined with PI3-kinase inhibition and VP-16. Morphological data indicated that LY-294002 and PKC 412 induced cell death at anaphase and metaphase, respectively, suggesting death by mitotic catastrophe. Analyzes of cells blocked in G2/M-phase by nocodazol revealed that LY-294002 increased, while PKC 412 decreased histone H3 phosphorylation, suggesting that LY-294002 allowed, while PKC 412 inhibited cells to leave M-phase. Flow cytometric analysis of cell cycle distribution demonstrated that LY-294002 allowed cells to leave G2/M phase, while PKC 412 inhibited cytokinesis, resulting in formation of multinucleated cells. These results indicate that sensitization of NSCLC cells by PI3-kinase inhibition involves interplay between cell cycle regulation, mitotic catastrophe and apoptosis.
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Affiliation(s)
- Therese H Hemström
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
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