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Ruiz-Cantos M, Hutchison CE, Shoulders CC. Musings from the Tribbles Research and Innovation Network. Cancers (Basel) 2021; 13:cancers13184517. [PMID: 34572744 PMCID: PMC8467127 DOI: 10.3390/cancers13184517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 09/02/2021] [Accepted: 09/04/2021] [Indexed: 11/16/2022] Open
Abstract
This commentary integrates historical and modern findings that underpin our understanding of the cell-specific functions of the Tribbles (TRIB) proteins that bear on tumorigenesis. We touch on the initial discovery of roles played by mammalian TRIB proteins in a diverse range of cell-types and pathologies, for example, TRIB1 in regulatory T-cells, TRIB2 in acute myeloid leukaemia and TRIB3 in gliomas; the origins and diversity of TRIB1 transcripts; microRNA-mediated (miRNA) regulation of TRIB1 transcript decay and translation; the substantial conformational changes that ensue on binding of TRIB1 to the transcription factor C/EBPα; and the unique pocket formed by TRIB1 to sequester its C-terminal motif bearing a binding site for the E3 ubiquitin ligase COP1. Unashamedly, the narrative is relayed through the perspective of the Tribbles Research and Innovation Network, and its establishment, progress and future ambitions: the growth of TRIB and COP1 research to hasten discovery of their cell-specific contributions to health and obesity-related cancers.
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Lorenzo GD, Zappavigna S, Crocetto F, Giuliano M, Ribera D, Morra R, Scafuri L, Verde A, Bruzzese D, Iaccarino S, Costabile F, Onofrio L, Viggiani M, Palmieri A, De Placido P, Marretta AL, Pietroluongo E, Luce A, Abate M, Navaeiseddighi Z, Caputo VF, Celentano G, Longo N, Ferro M, Morelli F, Facchini G, Caraglia M, De Placido S, Buonerba C. Assessment of Total, PTEN -, and AR-V7 + Circulating Tumor Cell Count by Flow Cytometry in Patients with Metastatic Castration-Resistant Prostate Cancer Receiving Enzalutamide. Clin Genitourin Cancer 2021; 19:e286-e298. [PMID: 33958297 DOI: 10.1016/j.clgc.2021.03.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 03/22/2021] [Accepted: 03/27/2021] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Metastatic castration-resistant prostate cancer (mCRPC) is a deadly disease. Enzalutamide is an oral second-generation anti-androgen that is active in mCRPC. Circulating tumor cells (CTC) count correlates with overall survival (OS) in mCRPC, whereas detection of the androgen-receptor splice variant 7 (AR-V7) in CTC predicts poor response to oral second-generation anti-androgens. Also, loss of PTEN (phosphatase and tensin homolog) in CTC is a biomarker of poor prognosis in mCRPC. PATIENTS AND METHODS In this translational study, we employed flow cytometry to assess total, PTEN-, and AR-V7+ CTC count per 7.5 mL of whole blood in a prospective cohort of patients with mCRPC receiving enzalutamide. RESULTS CTCs were assessed in a total of 45 men with mCRPC at baseline and at 12 weeks. Overall, CTC, PTEN- CTC, and AR-V7+ CTC detection rate was high, at baseline, with 84.4%, 71.1%, and 51.1% of samples showing at least 1 cell/7.5-mL blood, respectively, and after 3 months, with 93.3%, 64.4%, and 77.7% of samples showing at least 1 cell/7.5-mL blood, respectively. Median radiographic progression-free survival (rPFS) and OS were 6 (95% confidence interval [CI], 5.6-9) and 14.3 (95% CI, 12.8-20.3) months, respectively. Median (interquartile range) total CTC count at baseline was 5 (3; 8), whereas median (interquartile range) PTEN- CTC count was 2 (0; 4) and median (interquartile range) AR-V7+ CTC count was 1 (0; 3). At baseline, ≥ 5 versus < 5 total CTC count was associated with worse rPFS (hazard ratio [HR], 2.35; 95% CI, 1.14-4.84; P= .021) and OS (HR, 3.08; 95% CI, 1.45-6.54; P = .003), whereas ≥ 2 versus < 2 PTEN- CTC count was associated with worse rPFS (HR, 3.96; 95% CI, 1.8-8.72; P= .001) and OS (HR, 2.36; 95% CI, 1.12-5; P= .025). Finally, ≥ 1 versus < 1 AR-V7+ CTC count was also associated with worse rPFS (HR, 5.05; 95% CI, 2.4-10.64; P< .001) and OS (HR, 2.25; 95% CI, 1.1-4.58; P= .026). CONCLUSIONS Despite multiple limitations, including the small sample size, our preliminary study suggests that assessment of CTC via flow cytometry may provide potentially useful prognostic and predictive information in advanced prostate cancer. Further studies are warranted. Micro-Abstract: In this study, men with metastatic castration-resistant prostate cancer, scheduled to start enzalutamide, were assessed for circulating tumor cell count and molecular characterization (total, PTEN-, and AR-V7+ circulating tumor cell count) by the use of flow cytometry. We found that flow cytometry could be used to enumerate circulating tumor cells, but also to assess molecular biomarkers on their surface.
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Affiliation(s)
- Giuseppe Di Lorenzo
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy; Department of Medicine and Health Sciences "Vincenzo Tiberio," University of Molise, Campobasso, Italy; Department of Oncology, Hospital "Andrea Tortora," ASL Salerno, Pagani, Italy; Department of Oncology and Hematology, AOU Federico II of Naples, Naples, Italy
| | - Silvia Zappavigna
- Department of Precision Medicine, University of Campania "L. Vanvitelli," Naples, Italy
| | - Felice Crocetto
- Department of Neurosciences, Human Reproduction and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Mario Giuliano
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy; Regional Reference Center for Rare Tumors, Department of Oncology and Hematology, AOU Federico II of Naples, Naples, Italy
| | - Dario Ribera
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Rocco Morra
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Luca Scafuri
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Antonio Verde
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Dario Bruzzese
- Department of Public Health, University of Naples "Federico II," Naples, Italy
| | - Simona Iaccarino
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Ferdinando Costabile
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Livia Onofrio
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Martina Viggiani
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Alessandro Palmieri
- Department of Neurosciences, Human Reproduction and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Pietro De Placido
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | | | - Erica Pietroluongo
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy
| | - Amalia Luce
- Department of Precision Medicine, University of Campania "L. Vanvitelli," Naples, Italy
| | - Marianna Abate
- Department of Precision Medicine, University of Campania "L. Vanvitelli," Naples, Italy
| | | | - Vincenzo Francesco Caputo
- Department of Neurosciences, Human Reproduction and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Giuseppe Celentano
- Department of Neurosciences, Human Reproduction and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Nicola Longo
- Department of Neurosciences, Human Reproduction and Odontostomatology, University of Naples Federico II, Naples, Italy
| | - Matteo Ferro
- Division of Urology, European Institute of Oncology-IRCCS, Milan, Italy
| | - Franco Morelli
- Medical Oncology Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| | - Gaetano Facchini
- Departmental Unit of Experimental Uro-Andrological Clinical Oncology, Department of Uro-Gynaecological Oncology, National Cancer Institute-IRCCS-G. Pascale Foundation, Naples, Italy
| | - Michele Caraglia
- Department of Precision Medicine, University of Campania "L. Vanvitelli," Naples, Italy; Biogem Scarl, Institute of Genetic Research, Laboratory of Precision Medicine and Molecular Oncology, Ariano Irpino, Italy
| | - Sabino De Placido
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy; Regional Reference Center for Rare Tumors, Department of Oncology and Hematology, AOU Federico II of Naples, Naples, Italy
| | - Carlo Buonerba
- Department of Clinical Medicine and Surgery, University Federico II of Naples, Naples, Italy; Regional Reference Center for Rare Tumors, Department of Oncology and Hematology, AOU Federico II of Naples, Naples, Italy.
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ROR2 suppresses metastasis of prostate cancer via regulation of miR-199a-5p-PIAS3-AKT2 signaling axis. Cell Death Dis 2020; 11:376. [PMID: 32415173 PMCID: PMC7228945 DOI: 10.1038/s41419-020-2587-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 04/01/2020] [Accepted: 04/01/2020] [Indexed: 12/18/2022]
Abstract
Bones are the most common metastatic sites for prostate cancer (PCa). Receptor tyrosine kinase-like orphan receptor 2 (ROR2), a noncanonical Wnt receptor, plays crucial roles in skeletal morphogenesis, osteoblast differentiation, and bone formation. The role of ROR2 in PCa metastasis is unclear. We analyzed online datasets from Oncomine as well as using IHC staining on tissue array to determine the relationship between ROR2 expression level and disease outcome of PCa. To investigate how ROR2 regulates migration and invasion of PCa cells, we performed transwell assay and orthotopic xenograft model in nude mice. We then applied the Micro-Western Array (MWA), a high-throughput western blotting platform to analyze the downstream signaling pathways being regulated by ROR2. Compared with nonmalignant PZ-HPV-7 and RWPE-1 cells, PCa cell lines express lower level of ROR2 protein. Constitutive expression of ROR2 in PC-3, DU-145, or C4-2B PCa cells significantly suppressed the cell migration, invasion, and epithelial-mesenchymal transition (EMT) proteins. MWA, western blotting, and microRNA analysis showed that elevation of ROR2 suppressed the expression of miR-199a-5p, which in turn increased the expression of PIAS3. The upregulation of PIAS3 then decreased AKT2 and the phosphorylation of AKT, resulting in the inhibition of migration and invasion of PCa cells both in vitro and in orthotopic xenograft mice model. IHC staining of tissue array and Oncomine datasets analysis indicated that the gene and protein level of ROR2 is much lower in metastatic prostate tumors as compared with primary tumors or adjacent normal prostate tissues. Low level of ROR2 correlated to poor survival and high recurrent frequency in PCa patients. In conclusion, we discovered that ROR2 suppresses PCa metastasis via regulation of PIAS3-PI3K-AKT2 signaling axis.
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Hsu JL, Leu WJ, Hsu LC, Liu SP, Zhong NS, Guh JH. Para-Toluenesulfonamide Induces Anti-tumor Activity Through Akt-Dependent and -Independent mTOR/p70S6K Pathway: Roles of Lipid Raft and Cholesterol Contents. Front Pharmacol 2018; 9:1223. [PMID: 30555320 PMCID: PMC6282052 DOI: 10.3389/fphar.2018.01223] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 10/08/2018] [Indexed: 12/12/2022] Open
Abstract
Castration-resistant prostate cancer (CRPC) cells can resist many cellular stresses to ensure survival. There is an unmet medical need to fight against the multiple adaptive mechanisms in cells to achieve optimal treatment in patients. Para-toluenesulfonamide (PTS) is a small molecule that inhibited cell proliferation of PC-3 and DU-145, two CRPC cell lines, through p21- and p27-independent G1 arrest of cell cycle in which cyclin D1 was down-regulated and Rb phosphorylation was inhibited. PTS also induced a significant loss of mitochondrial membrane potential that was attributed to up-regulation of both Bak and PUMA, two pro-apoptotic Bcl-2 family members, leading to apoptosis. PTS inhibited the phosphorylation of m-TOR, 4E-BP1, and p70S6K in both cell lines. Overexpression of constitutively active Akt rescued the inhibition of mTOR/p70S6K signaling in PC-3 cells indicating an Akt-dependent pathway. In contrast, Akt-independent effect was observed in DU-145 cells. Lipid rafts serve as functional platforms for multiple cellular signaling and trafficking processes. Both cell lines expressed raft-associated Akt, mTOR, and p70S6K. PTS induced decreases of expressions in both raft-associated total and phosphorylated forms of these kinases. PTS-induced inhibitory effects were rescued by supplement of cholesterol, an essential constituent in lipid raft, indicating a key role of cholesterol contents. Moreover, the tumor xenograft model showed that PTS inhibited tumor growth with a T/C (treatment/control) of 0.44 and a 56% inhibition of growth rate indicating the in vivo efficacy. In conclusion, the data suggest that PTS is an effective anti-tumor agent with in vitro and in vivo efficacies through inhibition of both Akt-dependent and -independent mTOR/p70S6K pathways. Moreover, disturbance of lipid raft and cholesterol contents may at least partly explain PTS-mediated anti-tumor mechanism.
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Affiliation(s)
- Jui-Ling Hsu
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Wohn-Jenn Leu
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Lih-Ching Hsu
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shih-Ping Liu
- Department of Urology, College of Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Nan-Shan Zhong
- State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute for Respiratory Health, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Jih-Hwa Guh
- School of Pharmacy, College of Medicine, National Taiwan University, Taipei, Taiwan
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Tran LNK, Kichenadasse G, Sykes PJ. Combination Therapies Using Metformin and/or Valproic Acid in Prostate Cancer: Possible Mechanistic Interactions. Curr Cancer Drug Targets 2018; 19:368-381. [PMID: 30039761 DOI: 10.2174/1568009618666180724111604] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 05/25/2018] [Accepted: 07/10/2018] [Indexed: 12/22/2022]
Abstract
Prostate cancer (PCa) is the most frequent cancer in men. The evolution from local PCa to castration-resistant PCa, an end-stage of disease, is often associated with changes in genes such as p53, androgen receptor, PTEN, and ETS gene fusion products. Evidence is accumulating that repurposing of metformin (MET) and valproic acid (VPA) either when used alone, or in combination, with another therapy, could potentially play a role in slowing down PCa progression. This review provides an overview of the application of MET and VPA, both alone and in combination with other drugs for PCa treatment, correlates the responses to these drugs with common molecular changes in PCa, and then describes the potential for combined MET and VPA as a systemic therapy for prostate cancer, based on potential interacting mechanisms.
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Affiliation(s)
- Linh N K Tran
- Flinders Centre for Innovation in Cancer, Flinders University and Medical Centre, Bedford Park, Adelaide, Australia.,University of Medicine and Pharmacy at Ho Chi Minh City, Vietnam
| | - Ganessan Kichenadasse
- Flinders Centre for Innovation in Cancer, Flinders University and Medical Centre, Bedford Park, Adelaide, Australia
| | - Pamela J Sykes
- Flinders Centre for Innovation in Cancer, Flinders University and Medical Centre, Bedford Park, Adelaide, Australia
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Jäntti MH, Talman V, Räsänen K, Tarvainen I, Koistinen H, Tuominen RK. Anticancer activity of the protein kinase C modulator HMI-1a3 in 2D and 3D cell culture models of androgen-responsive and androgen-unresponsive prostate cancer. FEBS Open Bio 2018; 8:817-828. [PMID: 29744295 PMCID: PMC5929934 DOI: 10.1002/2211-5463.12419] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 03/08/2018] [Accepted: 03/13/2018] [Indexed: 01/19/2023] Open
Abstract
Prostate cancer is one of the most common cancers in men. Although it has a relatively high 5‐year survival rate, development of resistance to standard androgen‐deprivation therapy is a significant clinical problem. Therefore, novel therapeutic strategies are urgently needed. The protein kinase C (PKC) family is a putative prostate cancer drug target, but so far no PKC‐targeting drugs are available for clinical use. By contrast to the standard approach of developing PKC inhibitors, we have developed isophthalate derivatives as PKC agonists. In this study, we have characterized the effects of the most potent isophthalate, 5‐(hydroxymethyl)isophthalate 1a3 (HMI‐1a3), on three prostate cancer cell lines (LNCaP, DU145, and PC3) using both 2D and 3D cell culture models. In 2D cell culture, HMI‐1a3 reduced cell viability or proliferation in all cell lines as determined by the metabolic activity of the cells (3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐tetrazolium bromide assay) and thymidine incorporation. However, the mechanism of action in LNCaP cells was different to that in DU145 or PC3 cells. In LNCaP cells, HMI‐1a3 induced a PKC‐dependent activation of caspase 3/7, indicating an apoptotic response, whereas in DU145 and PC3 cells, it induced senescence, which was independent of PKC. This was observed as typical senescent morphology, increased β‐galactosidase activity, and upregulation of the senescence marker p21 and downregulation of E2F transcription factor 1. Using a multicellular spheroid model, we further showed that HMI‐1a3 affects the growth of LNCaP and DU145 cells in a 3D culture, emphasizing its potential as a lead compound for cancer drug development.
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Affiliation(s)
- Maria H Jäntti
- Department of Pharmacology and Pharmacotherapy University of Helsinki Finland
| | - Virpi Talman
- Department of Pharmacology and Pharmacotherapy University of Helsinki Finland
| | - Kati Räsänen
- Department of Clinical Chemistry Medicum University of Helsinki and Helsinki University Hospital Finland
| | - Ilari Tarvainen
- Department of Pharmacology and Pharmacotherapy University of Helsinki Finland
| | - Hannu Koistinen
- Department of Clinical Chemistry Medicum University of Helsinki and Helsinki University Hospital Finland
| | - Raimo K Tuominen
- Department of Pharmacology and Pharmacotherapy University of Helsinki Finland
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Schecher S, Walter B, Falkenstein M, Macher-Goeppinger S, Stenzel P, Krümpelmann K, Hadaschik B, Perner S, Kristiansen G, Duensing S, Roth W, Tagscherer KE. Cyclin K dependent regulation of Aurora B affects apoptosis and proliferation by induction of mitotic catastrophe in prostate cancer. Int J Cancer 2017; 141:1643-1653. [PMID: 28670704 DOI: 10.1002/ijc.30864] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/30/2017] [Accepted: 06/12/2017] [Indexed: 12/11/2022]
Abstract
Cyclin K plays a critical role in transcriptional regulation as well as cell development. However, the role of Cyclin K in prostate cancer is unknown. Here, we describe the impact of Cyclin K on prostate cancer cells and examine the clinical relevance of Cyclin K as a biomarker for patients with prostate cancer. We show that Cyclin K depletion in prostate cancer cells induces apoptosis and inhibits proliferation accompanied by an accumulation of cells in the G2/M phase. Moreover, knockdown of Cyclin K causes mitotic catastrophe displayed by multinucleation and spindle multipolarity. Furthermore, we demonstrate a Cyclin K dependent regulation of the mitotic kinase Aurora B and provide evidence for an Aurora B dependent induction of mitotic catastrophe. In addition, we show that Cyclin K expression is associated with poor biochemical recurrence-free survival in patients with prostate cancer treated with an adjuvant therapy. In conclusion, targeting Cyclin K represents a novel, promising anti-cancer strategy to induce cell cycle arrest and apoptotic cell death through induction of mitotic catastrophe in prostate cancer cells. Moreover, our results indicate that Cyclin K is a putative predictive biomarker for clinical outcome and therapy response for patients with prostate cancer.
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Affiliation(s)
- Sabrina Schecher
- Molecular Tumor-Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute of Pathology, University of Heidelberg, Heidelberg, Germany.,Institute of Pathology, University Medical Center Mainz, Mainz, Germany
| | - Britta Walter
- Institute of Pathology, University of Heidelberg, Heidelberg, Germany
| | - Michael Falkenstein
- Molecular Urooncology, Department of Urology, University of Heidelberg, Heidelberg, Germany
| | - Stephan Macher-Goeppinger
- Molecular Tumor-Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute of Pathology, University of Heidelberg, Heidelberg, Germany.,Institute of Pathology, University Medical Center Mainz, Mainz, Germany
| | - Philipp Stenzel
- Institute of Pathology, University Medical Center Mainz, Mainz, Germany
| | | | - Boris Hadaschik
- Department of Urology, Essen University Hospital, Essen, Germany.,Department of Urology, University of Heidelberg, Heidelberg, Germany
| | - Sven Perner
- Pathology of the University Medical Center Schleswig-Holstein, Campus Luebeck and the Research Center Borstel, Leibniz Center for Medicine and Biosciences, 23538 Luebeck and 23845 Borstel, Germany
| | | | - Stefan Duensing
- Molecular Urooncology, Department of Urology, University of Heidelberg, Heidelberg, Germany
| | - Wilfried Roth
- Molecular Tumor-Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute of Pathology, University of Heidelberg, Heidelberg, Germany.,Institute of Pathology, University Medical Center Mainz, Mainz, Germany
| | - Katrin E Tagscherer
- Molecular Tumor-Pathology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute of Pathology, University of Heidelberg, Heidelberg, Germany.,Institute of Pathology, University Medical Center Mainz, Mainz, Germany
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KIF7 attenuates prostate tumor growth through LKB1-mediated AKT inhibition. Oncotarget 2017; 8:54558-54571. [PMID: 28903364 PMCID: PMC5589603 DOI: 10.18632/oncotarget.17421] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 01/10/2017] [Indexed: 12/26/2022] Open
Abstract
This study investigated kinesin family member 7 (KIF7) expression and function in prostate cancer (PCa). Our results showed that KIF7 was significantly downregulated in PCa, compared with normal, benign prostatic hyperplasia and prostate intraepithelial neoplasia tissues, partially through promoter hypermethylation. We further investigated the effects of KIF7 coiled coil (CC) domain and motor domain (MD) on PCa development in vitro and in vivo. Our results showed that KIF7-CC but not KIF7-MD significantly attenuated proliferation and colony formation, impeded migration and invasion, induced apoptosis and sensitized PCa cells to paclitaxel. Further analysis revealed that KIF7-CC enhanced LKB1 expression and phosphorylation at Ser428, which induced PTEN phosphorylation at Ser380/Thr382/383 and consequently blocked AKT phosphorylation at Ser473. Downregulation of LKB1 significantly attenuated the suppressive effects of KIF7-CC on cell proliferation, colony formation and AKT phosphorylation. Furthermore, our in vivo studies showed that KIF7-CC reduced prostate tumorigenesis in cell-derived xenografts. Downregulation of LKB1 abrogated the anti-tumor effects of KIF7-CC in these xenografts. Taken together, these findings provide the first evidence to support the role of KIF7 as a negative regulator that inhibits PCa development partially through LKB1-mediated AKT inhibition.
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Ci X, Xing C, Zhang B, Zhang Z, Ni JJ, Zhou W, Dong JT. KLF5 inhibits angiogenesis in PTEN-deficient prostate cancer by attenuating AKT activation and subsequent HIF1α accumulation. Mol Cancer 2015; 14:91. [PMID: 25896712 PMCID: PMC4417294 DOI: 10.1186/s12943-015-0365-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 04/10/2015] [Indexed: 12/20/2022] Open
Abstract
Background KLF5 is a basic transcriptional factor that regulates multiple physiopathological processes. Our recent study showed that deletion of Klf5 in mouse prostate promotes tumorigenesis initiated by the deletion of Pten. While molecular characterization of Klf5-null tumors suggested that angiogenesis was partially responsible for tumor promotion, the precise function and mechanism of KLF5 deletion in prostate tumor angiogenesis remain unclear. Results Applying histological staining to Pten-null mouse prostates, we observed that deletion of Klf5 significantly increased the number of microvessels, accompanied by the upregulation of multiple angiogenesis-related genes based on microarray analysis with MetaCore software. In human umbilical vein endothelial cells (HuVECs), tube formation and migration, both of which are indicators of angiogenic activities, were decreased by conditioned media from PC-3 and DU 145 human prostate cancer cells with KLF5 overexpression, but increased by media from cells with KLF5 knockdown. HIF1α, a key angiogenesis inducer, was upregulated by KLF5 loss at the protein but not the mRNA level in both mouse tissues and human cell lines, as determined by immunohistochemical staining, real-time RT-PCR and Western blotting. Consistently, KLF5 loss also upregulated VEGF and PDGF, two pro-angiogenic mediators of HIF1α function, as analyzed by immunohistochemical staining in mouse tissues and ELISA in conditioned media. Mechanistically, AKT activity, which caused the accumulation of HIF1α, was increased by KLF5 knockout or knockdown but decreased by KLF5 overexpression. PI3K/AKT inhibitors consistently abolished the effects of KLF5 knockdown on angiogenic activity, HIF1α accumulation, and VEGF and PDGF expression. Conclusion KLF5 loss enhances tumor angiogenesis by attenuating PI3K/AKT signaling and subsequent accumulation of HIF1α in PTEN deficient prostate tumors. Electronic supplementary material The online version of this article (doi:10.1186/s12943-015-0365-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xinpei Ci
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin, 300071, China. .,Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
| | - Changsheng Xing
- Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
| | - Baotong Zhang
- Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
| | - Zhiqian Zhang
- Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
| | - Jenny Jianping Ni
- Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
| | - Wei Zhou
- Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
| | - Jin-Tang Dong
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, 94 Weijin Road, Tianjin, 300071, China. .,Department of Hematology and Medical Oncology, Emory Winship Cancer Institute, Emory University School of Medicine, 1365-C Clifton Road, Atlanta, GA, 30322, USA.
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10
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Xing C, Ci X, Sun X, Fu X, Zhang Z, Dong EN, Hao ZZ, Dong JT. Klf5 deletion promotes Pten deletion-initiated luminal-type mouse prostate tumors through multiple oncogenic signaling pathways. Neoplasia 2014; 16:883-99. [PMID: 25425963 PMCID: PMC4240924 DOI: 10.1016/j.neo.2014.09.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/13/2014] [Accepted: 09/22/2014] [Indexed: 01/18/2023] Open
Abstract
Krüppel-like factor 5 (KLF5) regulates multiple biologic processes. Its function in tumorigenesis appears contradictory though, showing both tumor suppressor and tumor promoting activities. In this study, we examined whether and how Klf5 functions in prostatic tumorigenesis using mice with prostate-specific deletion of Klf5 and phosphatase and tensin homolog (Pten), both of which are frequently inactivated in human prostate cancer. Histologic analysis demonstrated that when one Pten allele was deleted, which causes mouse prostatic intraepithelial neoplasia (mPIN), Klf5 deletion accelerated the emergence and progression of mPIN. When both Pten alleles were deleted, which causes prostate cancer, Klf5 deletion promoted tumor growth, increased cell proliferation, and caused more severe morphologic and molecular alterations. Homozygous deletion of Klf5 was more effective than hemizygous deletion. Unexpectedly, while Pten deletion alone expanded basal cell population in a tumor as reported, Klf5 deletion in the Pten-null background clearly reduced basal cell population while expanding luminal cell population. Global gene expression profiling, pathway analysis, and experimental validation indicate that multiple mechanisms could mediate the tumor-promoting effect of Klf5 deletion, including the up-regulation of epidermal growth factor and its downstream signaling molecules AKT and ERK and the inactivation of the p15 cell cycle inhibitor. KLF5 also appears to cooperate with several transcription factors, including CREB1, Sp1, Myc, ER and AR, to regulate gene expression. These findings validate the tumor suppressor function of KLF5. They also yield a mouse model that shares two common genetic alterations with human prostate cancer—mutation/deletion of Pten and deletion of Klf5.
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Affiliation(s)
- Changsheng Xing
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, China ; Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
| | - Xinpei Ci
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, China ; Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
| | - Xiaodong Sun
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
| | - Xiaoying Fu
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA ; Department of Pathology, Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Zhiqian Zhang
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
| | - Eric N Dong
- Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
| | - Zhao-Zhe Hao
- Department of Biology, University of Oklahoma, Norman, OK, USA
| | - Jin-Tang Dong
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, China ; Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
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11
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Mahdian R, Nodouzi V, Asgari M, Rezaie M, Alizadeh J, Yousefi B, Shahrokh H, Abolhasani M, Nowroozi M. Expression profile of MAGI2 gene as a novel biomarker in combination with major deregulated genes in prostate cancer. Mol Biol Rep 2014; 41:6125-31. [PMID: 24985972 DOI: 10.1007/s11033-014-3491-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 06/17/2014] [Indexed: 12/11/2022]
Abstract
Complex molecular changes that occur during prostate cancer (PCa) progression have been described recently. Whole genome sequencing of primary PCa samples has identified recurrent gene deletions and rearrangements in PCa. Specifically, these molecular events disrupt the gene loci of phosphatase and tensin homolog (PTEN) and membrane-associated guanylate kinase inverted-2 (MAGI2). In the present study, we analyzed the expression profile of MAGI2 gene in a cohort of clinical PCa (n = 45) and benign prostatic hyperplasia (BPH) samples (n = 36) as well as three PCa cell lines. We also studied the expression of PCa-related genes, including PTEN, NKX3.1, SPINK1, DD3, AMACR, ERG, and TMPRSS2-ERG fusion in the same samples. The expression of MAGI2 mRNA was significantly down-regulated in PC3, LNCaP and DU-145 PCa cell lines (p = 0.000), and also in clinical tumor samples (Relative expression = 0.307, p = 0.002, [95 % CI 0.002-12.08]). The expression of PTEN, NKX3.1, SPINK1, DD3, and AMACR genes was significantly deregulated in prostate tumor samples (p range 0.000-0.044). A significant correlation was observed between MAGI2 and NKX3.1 expression in tumor samples (p = 0.006). Furthermore, the inclusion of MAGI2 in the gene panel improved the accuracy for discrimination between PCa and BPH samples with the sensitivity and specificity of 0.88 [CI 0.76-0.95] and 0.83 [CI 0.68-0.92], respectively. The data presented here suggest that MAGI2 gene can be considered as a novel component of gene signatures for the detection of PCa.
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Affiliation(s)
- Reza Mahdian
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, 1316943551, Iran,
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12
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Li Q, Fu GB, Zheng JT, He J, Niu XB, Chen QD, Yin Y, Qian X, Xu Q, Wang M, Sun AF, Shu Y, Rui H, Liu LZ, Jiang BH. NADPH oxidase subunit p22(phox)-mediated reactive oxygen species contribute to angiogenesis and tumor growth through AKT and ERK1/2 signaling pathways in prostate cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:3375-3385. [PMID: 24113386 DOI: 10.1016/j.bbamcr.2013.09.018] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 09/24/2013] [Accepted: 09/25/2013] [Indexed: 12/27/2022]
Abstract
Excessive generation of reactive oxygen species (ROS) in cancer cells is associated with cancer development, but the underlying mechanisms and therapeutic significance remain elusive. In this study, we reported that levels of ROS and p22(phox) expression are greatly increased in human prostate cancer tissues, and knockdown of p22(phox) by specific small interfering RNA (siRNA) decreased ROS levels in prostate cancer cells. We also showed that stable downregulation of p22(phox) in prostate cancer cells inhibited cell proliferation and colony formation, which was mediated by AKT and extracellular signal-regulated kinase (ERK)1/2 signaling pathways and their downstream molecules hypoxia-inducible factor 1α (HIF-1α) and vascular endothelial growth factor (VEGF). The NADPH oxidase subunit NOX1 was also elevated in prostate cancer cells, and was involved in activation of AKT/ERK/HIF-1/VEGF pathway and regulation of cell proliferation. Knockdown of p22(phox) resulted in inhibition of tumor angiogenesis and tumor growth in nude mice. These findings reveal a new function of p22(phox) in tumor angiogenesis and tumor growth, and suggest that p22(phox) is a potential novel target for prostate cancer treatment.
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Affiliation(s)
- Qi Li
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China
| | - Guang-Bo Fu
- Department of Urology and Pathology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an 223300, China
| | - Ji-Tai Zheng
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China
| | - Jun He
- Department of Pathology, Anatomy and Cell Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Xiao-Bing Niu
- Department of Urology and Pathology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an 223300, China
| | - Qiu-Dan Chen
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China
| | - Yu Yin
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China; Department of Pathology, Anhui Medical University, Hefei 230032, China
| | - Xu Qian
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China
| | - Qing Xu
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China
| | - Min Wang
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China
| | - An-Fang Sun
- Department of Urology and Pathology, Huai'an First People's Hospital, Nanjing Medical University, Huai'an 223300, China
| | - Yongqian Shu
- Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Hallgeir Rui
- Department of Pathology, Anatomy and Cell Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Ling-Zhi Liu
- Department of Pathology, Anatomy and Cell Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Bing-Hua Jiang
- State Key Lab of Reproductive Medicine, and Department of Pathology, Cancer Center, Nanjing Medical, Nanjing 210029, China; Department of Pathology, Anatomy and Cell Biology, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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13
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α-Mannosidase 2C1 attenuates PTEN function in prostate cancer cells. Nat Commun 2011; 2:307. [PMID: 21556061 DOI: 10.1038/ncomms1309] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 04/13/2011] [Indexed: 12/29/2022] Open
Abstract
PTEN dephosphorylates the 3-position phosphate of phosphatidylinositol 3,4,5 triphosphate (PIP(3)), thereby inhibiting AKT activation. Although attenuation of PTEN function has a major role in tumourigenesis, the underlying mechanisms remain unclear. Here we show that α-mannosidase 2C1 (MAN2C1) inhibits PTEN function in prostate cancer (PC) cells and is associated with a reduction in PTEN function in primary PC. MAN2C1 activates AKT and promotes the formation of PTEN-positive DU145 cell-derived xenograft tumours by imparing endogenous PTEN function. In 659 PC patients who were examined, ~60% of tumours were PTEN positive with elevated AKT activation. Of these, 80% display MAN2C1 overexpression that co-localizes with PTEN. Increases in MAN2C1 were detected only in PTEN-positive prostatic intraepithelial neoplasia and carcinomas, and showed a significant association with PC recurrence only in patients with PTEN-positive PCs. Mechanistically, MAN2C1 binds PTEN thereby inhibiting its PIP(3) phosphatase activity. These findings show that MAN2C1 function as a PTEN-negative regulator in PC cells.
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14
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Dizeyi N, Hedlund P, Bjartell A, Tinzl M, Austild-Taskén K, Abrahamsson PA. Serotonin activates MAP kinase and PI3K/Akt signaling pathways in prostate cancer cell lines. Urol Oncol 2011; 29:436-45. [PMID: 19926313 DOI: 10.1016/j.urolonc.2009.09.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 09/18/2009] [Accepted: 09/22/2009] [Indexed: 12/28/2022]
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15
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Chetram MA, Odero-Marah V, Hinton CV. Loss of PTEN permits CXCR4-mediated tumorigenesis through ERK1/2 in prostate cancer cells. Mol Cancer Res 2010; 9:90-102. [PMID: 21076047 DOI: 10.1158/1541-7786.mcr-10-0235] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Loss of PTEN is frequently observed in androgen-independent prostate cancer, resulting in the deregulation of metastatic events. SDF1α activation of CXCR4 induces signaling pathways that have been implicated in prostate metastasis and progression to an advanced disease. The pathways of CXCR4 and PTEN converge, leading to the promotion and regulation of tumorigenesis, respectively. However, loss of PTEN may permit CXCR4 to progress prostate cancer to an advanced disease. In the present study, we investigated the involvement of PTEN in CXCR4-mediated tumorigenesis. When screening advanced metastatic prostate cancer cell lines for PTEN, we observed a loss of expression in PC3 and LNCaP cells whereas Du145 expressed wild-type PTEN. All three cell lines were positive for surface expression of CXCR4. Reconsitution of PTEN induced a mesenchymal to epithelial like morphologic change and inhibited CXCR4-mediated migration and proliferation in PC3 cells. Downregulation of PTEN by siRNA enhanced the CXCR4-mediated migratory behavior of Du145 cells. By Western blot analysis, we observed that PTEN inhibited basal AKT phosphorylation but not ERK1/2 phosphorylation in PTEN-expressing cells. Upon CXCR4 stimulation, PTEN inhibited ERK1/2 phosphorylation but not phosphorylation of AKT. The CXCR4-mediated migration of PC3 cells was through the ERK1/2 pathway, as confirmed by chemical inhibitors. On the basis of these studies, we suggest that loss of PTEN permits CXCR4-mediated functions in prostate cancer cells through the ERK1/2 pathway. Antagonizing CXCR4 and downstream signaling cascades may provide an efficient approach for treating patients with advanced prostate cancer when hormone therapy fails to the stop the growth and containment of tumors.
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Affiliation(s)
- Mahandranauth A Chetram
- Clark Atlanta University, Center for Cancer Research and Therapeutic Development, 223 James P. Brawley Drive, SW, Atlanta, GA 30314, USA
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16
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He L, Ingram A, Rybak AP, Tang D. Shank-interacting protein-like 1 promotes tumorigenesis via PTEN inhibition in human tumor cells. J Clin Invest 2010; 120:2094-108. [PMID: 20458142 DOI: 10.1172/jci40778] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 03/17/2010] [Indexed: 01/26/2023] Open
Abstract
Inactivation of phosphatase and tensin homolog (PTEN) is a critical step during tumorigenesis, and PTEN inactivation by genetic and epigenetic means has been well studied. There is also evidence suggesting that PTEN negative regulators (PTEN-NRs) have a role in PTEN inactivation during tumorigenesis, but their identity has remained elusive. Here we have identified shank-interacting protein-like 1 (SIPL1) as a PTEN-NR in human tumor cell lines and human primary cervical cancer cells. Ectopic SIPL1 expression protected human U87 glioma cells from PTEN-mediated growth inhibition and promoted the formation of HeLa cell-derived xenograft tumors in immunocompromised mice. Conversely, siRNA-mediated knockdown of SIPL1 expression inhibited the growth of both HeLa cells and DU145 human prostate carcinoma cells in vitro and in vivo in a xenograft tumor model. These inhibitions were reversed by concomitant knockdown of PTEN, demonstrating that SIPL1 affects tumorigenesis via inhibition of PTEN function. Mechanistically, SIPL1 was found to interact with PTEN through its ubiquitin-like domain (UBL), inhibiting the phosphatidylinositol 3,4,5-trisphosphate (PIP3) phosphatase activity of PTEN. Furthermore, SIPL1 expression correlated with loss of PTEN function in PTEN-positive human primary cervical cancer tissue. Taken together, these observations indicate that SIPL1 is a PTEN-NR and that it facilitates tumorigenesis, at least in part, through its PTEN inhibitory function.
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Affiliation(s)
- Lizhi He
- Division of Nephrology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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17
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Zhang KX, Moussavi M, Kim C, Chow E, Chen IS, Fazli L, Jia W, Rennie PS. Lentiviruses with trastuzumab bound to their envelopes can target and kill prostate cancer cells. Cancer Gene Ther 2009; 16:820-31. [PMID: 19373278 DOI: 10.1038/cgt.2009.28] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In this study, we took advantage of the overexpression of human epidermal growth factor receptor 2 (HER-2) in prostate cancers to design lentiviruses with modified envelope proteins that bind antibodies to specific cell-surface antigens. When bound to trastuzumab (Herceptin, Genentech, CA), lentiviruses were able to selectively infect androgen-sensitive LNCaP and castration-resistant C4-2 human prostate cancer cell lines, both of which express high levels of HER-2. To test for a therapeutic effect, we engineered our antibody-binding lentiviruses to express thymidine kinase, which can convert the non-toxic pro-drug ganciclovir (GCV) into a cytotoxic form. LNCaP and C4-2 cells infected by these viruses were sensitive to GCV killing. In vivo, C4-2 xenograft tumors treated either intratumorally or i.v. with trastuzumab-bound lentivirus expressed luciferase, although the latter route was less tumor specific. When a prostate-specific promoter for governing luciferase expression was combined with trastuzumab-mediated delivery, there was a further enrichment in targeting viral gene expression in prostate tumors. In conclusion, we found that although prostate cancers that express high levels of HER-2 are resistant to the killing effects of trastuzumab, they can be targeted for selective gene expression and destruction by viruses with envelope proteins engineered to bind this antibody.
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Affiliation(s)
- K-x Zhang
- Prostate Centre at Vancouver General Hospital, Vancouver, British Columbia, Canada V6H 3Z6
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18
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Unterluggauer H, Hütter E, Viertler HP, Jansen-Dürr P. Insulin-like growth factor-induced signals activate mitochondrial respiration. Biotechnol J 2008; 3:813-6. [PMID: 18383021 DOI: 10.1002/biot.200700254] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
From experiments with lower eukaryotes it is known that the metabolic rate and also the rate of aging are tightly controlled by the insulin-like growth factor (IGF)/insulin signal transduction pathway. The mitochondrial theory of aging implies that an increased metabolic rate leads to increased mitochondrial activity; increased production of reactive oxygen species due to these alterations would speed up the aging process. To address the question if mitochondrial activity is influenced by insulin/IGF signaling, we have established an experimental system to determine the influence of IGF-I-dependent signaling on mitochondrial function. We used DU145 prostate cancer cells, known for the intact IGF signal transduction pathway, to address the influence of IGF receptor activation on mitochondrial function by high-resolution respirometry. These experiments revealed that indeed mitochondrial function is regulated by IGF signaling, and up-regulation of respiration seems to require phosphoinositide 3-kinase/AKT signaling, but is independent of IGF effects on cell cycle progression. Collectively these data establish a regulatory cross-talk between insulin/IGF signal transduction and mitochondrial function, two major pathways implicated in controlling the rate of aging.
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Affiliation(s)
- Hermann Unterluggauer
- Institute for Biomedical Aging Research, Austrian Academy of Sciences, Innsbruck, Austria
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19
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Li Z, Wang L, Zhang W, Fu Y, Zhao H, Hu Y, Prins BP, Zha X. Restoring E-cadherin-mediated cell–cell adhesion increases PTEN protein level and stability in human breast carcinoma cells. Biochem Biophys Res Commun 2007; 363:165-70. [PMID: 17845801 DOI: 10.1016/j.bbrc.2007.08.154] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 08/22/2007] [Indexed: 11/28/2022]
Abstract
The phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a well-characterized tumor suppressor that negatively regulates cell growth and survival. Despite the critical role of PTEN in cell signaling, the mechanisms of its regulation are still under investigation. We reported here that PTEN expression could be controlled by overexpression or knock-down of E-cadherin in several mammary carcinoma cell lines. Furthermore, we showed that the accumulation of PTEN protein in E-cadherin overexpressing cells was due to increased PTEN protein stability rather than the regulation of its transcription. The proteasome-dependent PTEN degradation pathway was impaired after restoring E-cadherin expression. Moreover, maintenance of E-cadherin mediated cell-cell adhesion was necessary for its regulating PTEN. Altogether, our results suggested that E-cadherin mediated cell-cell adhesion was essential for preventing the proteasome degradation of PTEN, which might explain how breast carcinoma cells which lost cell-cell contact proliferate rapidly and are prone to metastasis.
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Affiliation(s)
- Zengxia Li
- Key Laboratory of Glycoconjugate Research, Ministry of Health, Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, 138 Yi Xue Yuan Road, Shanghai 200032, China
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20
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Zhang M, Fang X, Liu H, Guo R, Wu X, Li B, Zhu F, Ling Y, Griffith BN, Wang S, Yang D. Bioinformatics-based discovery and characterization of an AKT-selective inhibitor 9-chloro-2-methylellipticinium acetate (CMEP) in breast cancer cells. Cancer Lett 2007; 252:244-58. [PMID: 17293030 DOI: 10.1016/j.canlet.2006.12.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2006] [Accepted: 12/27/2006] [Indexed: 01/07/2023]
Abstract
AKT is a promising target for anticancer drug development. In this work, a bioinformatics approach was applied to search for AKT inhibitors based on the correlation analysis between phospho-Ser473 AKT expression level and the antiproliferative data of NCI small molecule compounds against NCI 60 cancer cell lines, the candidate compounds were then subject to AKT kinase assay. The possible effects of potent compound on PI3K/AKT, PDK1, and MAPK, its antiproliferative and apoptosis-inducing effects on breast cancer cells which have high-levels of AKT activation were assessed by Western blot analysis, cell viability assay, and apoptosis assay. One compound, CMEP (NSC632855, 9-chloro-2-methylellipticinium acetate) was identified with all three correlation algorithm, Pearson's, Sperman's, and Kendall's, showing a high-ranked correlation coefficient. CMEP inhibits only AKT, but does not inhibit PI3K, PDK1, or MAPK. CMEP also inhibits heregulin-induced AKT activation, does not inhibit heregulin-induced MAPK activation in MCF-7 breast cancer cells. Increased concentrations of ATP reverse the AKT inhibitory effect of CMEP. CMEP inhibits growth and induces apoptosis in breast cancer cells which have high-levels of AKT activation and lack functional PTEN; however, CMEP only shows a minimal activity in NIH3T3 cells which do not have AKT activation. In conclusion, a lead compound CMEP, as an AKT selective inhibitor has been identified started with a bioinformatics-based approach. CMEP inhibits growth and induces apoptosis in cancer cells which have high-levels of AKT activation and lack PTEN or harbor PTEN mutation.
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Affiliation(s)
- Manchao Zhang
- Department of Biochemistry and Molecular Pharmacology, West Virginia University, 1 Medical Center Drive, Morgantown, WV 26506-9142, USA.
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21
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Sainaghi PP, Castello L, Bergamasco L, Galletti M, Bellosta P, Avanzi GC. Gas6 induces proliferation in prostate carcinoma cell lines expressing the Axl receptor. J Cell Physiol 2005; 204:36-44. [PMID: 15605394 DOI: 10.1002/jcp.20265] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Axl is a tyrosine kinase receptor and although it is expressed in malignancy such as leukemia, colon cancer, melanoma, endometrial, prostate and thyroid cancers, its role has not been completely elucidated yet and appears to be complex. The ligand of Axl, Gas6, is a 75 KDa multimodular protein with an N-terminal gamma-carboxy-glutamic acid that is essential for binding. Gas6 has a mitogenic effect on several normal cell lines. The receptor Axl is expressed in primary prostate carcinoma and in prostate cancer cell lines as such as PC-3 and DU 145. We demonstrated a mitogenic activity determined by Gas6/Axl interaction in these undifferentiated metastatic human prostatic cancer cell lines. This effect is proportional to Axl expression, not due to inhibition of apoptosis, and induces AKT and MAPK phosphorylation. However, only MEK phosphorylation seems to be essential for growth signaling. Our results suggest that Axl overexpression and activation by Gas6 could be involved in progression of prostate neoplastic disease.
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Affiliation(s)
- Pier Paolo Sainaghi
- Department of Medical Sciences, Università del Piemonte Orientale "A. Avogadro," Novara, Italy
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22
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Selvan SR, Cornforth AN, Rao NP, Reid YA, Schiltz PM, Liao RP, Price DT, Heinemann FS, Dillman RO. Establishment and characterization of a human primary prostate carcinoma cell line, HH870. Prostate 2005; 63:91-103. [PMID: 15468172 DOI: 10.1002/pros.20162] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Development of new therapeutic modalities for human prostate carcinoma has been impeded by a lack of adequate in vitro and in vivo models. Most in vitro studies have been carried out using a limited number of human prostate cancer cell lines that are mostly derived from metastatic tumors sites or are immortalized. METHODS Characterization of the prostate cancer cell line, HH870, included description of morphology, determination of doubling time, response to androgens, immunocytochemistry, and immunoblotting of proteins known to be associated with prostate carcinoma, karyotyping, fluorescence in situ hybridization (FISH), DNA profiling, and growth as xenograft in athymic rodents. RESULTS HH870 expresses various epithelial marker antigens that correlate with known basic immunostaining profiles of prostate adenocarcinoma, although the cell line does not express PSA, PSMA, or PAP. HH870 exhibits complex chromosomal abnormalities and harbors no immortalizing HPV, BKV, JCV, and SV40 DNA. CONCLUSIONS We report the successful establishment and characterization of a new long-term primary human prostate tumor cell line HH870.
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Affiliation(s)
- Senthamil R Selvan
- Patty and George Hoag Cancer Center, Newport Beach, California 92663, USA.
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23
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Wu L, Birle DC, Tannock IF. Effects of the Mammalian Target of Rapamycin Inhibitor CCI-779 Used Alone or with Chemotherapy on Human Prostate Cancer Cells and Xenografts. Cancer Res 2005; 65:2825-31. [PMID: 15805283 DOI: 10.1158/0008-5472.can-04-3137] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Selective inhibition of repopulation of surviving tumor cells between courses of chemotherapy might improve the outcome of treatment. A potential target for inhibiting repopulation is the mammalian target of rapamycin pathway; PTEN-negative tumor cells are particularly sensitive to inhibition of this pathway. Here we study the rapamycin analogue CCI-779, alone or with chemotherapy, as an inhibitor of proliferation of the human prostate cancer cell lines PC-3 and DU145. The PTEN and phospho-Akt/PKB status and the effect of CCI-779 on phosphorylation of ribosomal protein S6 were evaluated by immunostaining and/or Western blotting. Expression of phospho-Akt/PKB in PTEN mutant PC-3 cells and xenografts was higher than in PTEN wild-type DU145 cells. Phosphorylation of S6 was inhibited by CCI-779 in both cell lines. Cultured cells were treated weekly with mitoxantrone or docetaxel for two cycles, and CCI-779 or vehicle was given between courses. Growth and clonogenic survival of both cell lines were inhibited in a dose-dependent manner by CCI-779, but there were minimal effects when CCI-779 was given between courses of chemotherapy. CCI-779 inhibited the growth of xenografts derived from both cell lines with greater effects against PC-3 than DU145 tumors. CCI-779 caused mild myelosuppression. The activity of mitoxantrone or docetaxel was limited, but CCI-779 given between courses of chemotherapy increased growth delay of PC-3 xenografts. Our results suggest that repopulation of PTEN-negative cancer cells between courses of chemotherapy might be inhibited by CCI-779.
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Affiliation(s)
- Licun Wu
- Department of Medical Oncology and Hematology and Division of Experimental Therapeutics, Princess Margaret Hospital and University of Toronto, Toronto, Ontario, Canada
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24
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Subauste MC, Nalbant P, Adamson ED, Hahn KM. Vinculin Controls PTEN Protein Level by Maintaining the Interaction of the Adherens Junction Protein β-Catenin with the Scaffolding Protein MAGI-2. J Biol Chem 2005; 280:5676-81. [PMID: 15579911 DOI: 10.1074/jbc.m405561200] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PTEN is a frequently mutated tumor suppressor in malignancies. Interestingly, some malignancies exhibit undetectable PTEN protein without mutations or loss of PTEN mRNA. The cause(s) for this reduction in PTEN is unknown. Cancer cells frequently exhibit loss of cadherin, beta-catenin, alpha-catenin and/or vinculin, key elements of adherens junctions. Here we show that F9 vinculin-null (vin(-/-)) cells lack PTEN protein despite normal PTEN mRNA levels. Their PTEN protein expression was restored by transfection with vinculin or by inhibition of PTEN degradation. F9 vin(-/-) cells express PTEN protein upon transfection with a vinculin fragment (amino acids 243-1066) that is capable of interacting with alpha-catenin but unable to target into focal adhesions. On the other hand, disruption of adherens junctions with an E-cadherin blocking antibody reduced PTEN protein to undetectable levels in wild-type F9 cells. PTEN protein levels were restored in F9 vin(-/-) cells upon transfection with an E-cadherin-alpha-catenin fusion protein, which targets into adherens junctions and interacts with beta-catenin in F9 vin(-/-) cells. beta-Catenin is known to interact with MAGI-2. MAGI-2 interaction with PTEN in the cell membrane is known to prevent PTEN protein degradation. Thus, MAGI-2 overexpression in F9 vin(-/-) cells restored PTEN protein levels. Moreover, expression of vinculin mutants that reinstated the disrupted interactions of beta-catenin with MAGI-2 in F9 vin(-/-) cells also restored PTEN protein levels. These studies indicate that PTEN protein levels are dependent on the maintenance of beta-catenin-MAGI-2 interaction, in which vinculin plays a critical role.
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Affiliation(s)
- M Cecilia Subauste
- Department of Cell Biology, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, USA.
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Seo JH, Ahn Y, Lee SR, Yeol Yeo C, Chung Hur K. The major target of the endogenously generated reactive oxygen species in response to insulin stimulation is phosphatase and tensin homolog and not phosphoinositide-3 kinase (PI-3 kinase) in the PI-3 kinase/Akt pathway. Mol Biol Cell 2005; 16:348-57. [PMID: 15537704 PMCID: PMC539178 DOI: 10.1091/mbc.e04-05-0369] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2004] [Revised: 10/22/2004] [Accepted: 10/27/2004] [Indexed: 12/22/2022] Open
Abstract
Phosphoinositide-3 kinase (PI-3 kinase) and its downstream signaling molecules PDK-1 and Akt were analyzed in SK-N-SH and SK-N-BE(2) human neuroblastoma cell lines. When cells were stimulated with insulin, PI-3 kinase was activated in both cell lines, whereas the translocation of PDK-1 to the membrane fraction and phosphorylated Akt were observed only in SK-N-SH cells. Analyses of the insulin-mediated reactive oxygen species (ROS) generation and Phosphatase and Tensin homolog (PTEN) oxidation indicate that PTEN oxidation occurred in SK-N-SH cells, which can produce ROS, but not in SK-N-BE(2) cells, which cannot increase ROS in response to insulin stimulation. When SK-N-SH cells were pretreated with the NADPH oxidase inhibitor diphenyleneiodonium chloride before insulin stimulation, insulin-mediated translocation of PDK-1 to the membrane fraction and phosphorylation of Akt were remarkably reduced, whereas PI-3 kinase activity was not changed significantly. These results indicate that not only PI-3 kinase activation but also inhibition of PTEN by ROS is needed to increase cellular level of phosphatidylinositol 3,4,5-trisphosphate for recruiting downstream signaling molecules such as PDK-1 and Akt in insulin-mediated signaling. Moreover, the ROS generated by insulin stimulation mainly contributes to the inactivation of PTEN and not to the activation of PI-3 kinase in the PI-3 kinase/Akt pathway.
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Affiliation(s)
- Ji Hae Seo
- Department of Biology, Ewha Women's University, Seoul 120-750, Korea
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26
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Abstract
Programmed cell death, or apoptosis, is a series of morphologically and biochemically related processes. The extrinsic (death receptor mediated) and intrinsic (mitochondrial-mediated) apoptotic pathways can be triggered by physiological and pharmacological substances. However, other molecular events influence the sensitivity of prostate cancer cells to apoptotic stimuli, leading to marked variations in the responsiveness of prostate cancer cell lines to individual stimuli. Modulation of apoptotic responses by over expression of anti-apoptotic proteins (NF-kappaB, IAPs and Bcl-2), or attenuation of pro-apoptotic proteins (PTEN and Bax) may be responsible for the variations in sensitivity of these cell lines to hormone and chemotherapy. The expression of anti- and pro-apoptotic proteins in some of the widely used in vitro models of prostate cancer is reviewed.
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Affiliation(s)
- E C Y Lee
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46656, USA
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Gao Y, Dickerson JB, Guo F, Zheng J, Zheng Y. Rational design and characterization of a Rac GTPase-specific small molecule inhibitor. Proc Natl Acad Sci U S A 2004; 101:7618-23. [PMID: 15128949 PMCID: PMC419655 DOI: 10.1073/pnas.0307512101] [Citation(s) in RCA: 919] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2003] [Accepted: 03/30/2004] [Indexed: 01/03/2023] Open
Abstract
The signaling pathways mediated by Rho family GTPases have been implicated in many aspects of cell biology. The specificity of the pathways is achieved in part by the selective interaction between Dbl family guanine nucleotide exchange factors (GEFs) and their Rho GTPase substrates. Here, we report a first-generation small-molecule inhibitor of Rac GTPase targeting Rac activation by GEF. The chemical compound NSC23766 was identified by a structure-based virtual screening of compounds that fit into a surface groove of Rac1 known to be critical for GEF specification. In vitro it could effectively inhibit Rac1 binding and activation by the Rac-specific GEF Trio or Tiam1 in a dose-dependent manner without interfering with the closely related Cdc42 or RhoA binding or activation by their respective GEFs or with Rac1 interaction with BcrGAP or effector PAK1. In cells, it potently blocked serum or platelet-derived growth factor-induced Rac1 activation and lamellipodia formation without affecting the activity of endogenous Cdc42 or RhoA. Moreover, this compound reduced Trio or Tiam1 but not Vav, Lbc, Intersectin, or a constitutively active Rac1 mutant-stimulated cell growth and suppressed Trio, Tiam1, or Ras-induced cell transformation. When applied to human prostate cancer PC-3 cells, it was able to inhibit the proliferation, anchorage-independent growth and invasion phenotypes that require the endogenous Rac1 activity. Thus, NSC23766 constitutes a Rac-specific small-molecule inhibitor that could be useful to study the role of Rac in various cellular functions and to reverse tumor cell phenotypes associated with Rac deregulation.
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Affiliation(s)
- Yuan Gao
- Division of Experimental Hematology, Children's Hospital Research Foundation, Cincinnati, OH 45229, USA
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28
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Niv MY, Rubin H, Cohen J, Tsirulnikov L, Licht T, Peretzman-Shemer A, Cna'an E, Tartakovsky A, Stein I, Albeck S, Weinstein I, Goldenberg-Furmanov M, Tobi D, Cohen E, Laster M, Ben-Sasson SA, Reuveni H. Sequence-based Design of Kinase Inhibitors Applicable for Therapeutics and Target Identification. J Biol Chem 2004; 279:1242-55. [PMID: 14570903 DOI: 10.1074/jbc.m306723200] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
A platform for specifically modulating kinase-dependent signaling using peptides derived from the catalytic domain of the kinase is presented. This technology, termed KinAce, utilizes the canonical structure of protein kinases. The targeted regions (subdomain V and subdomains IX and X) are analyzed and their sequence, three-dimensional structure, and involvement in protein-protein interaction are highlighted. Short myristoylated peptides were derived from the target regions of the tyrosine kinases c-Kit and Lyn and the serine/threonine kinases 3-phosphoinositide-dependent kinase-1 (PDK1) and Akt/protein kinase B (PKB). For each kinase an active designer peptide is shown to selectively inhibit the signaling of the kinase from which it is derived, and to inhibit cancer cell proliferation in the micromolar range. This technology emerges as an applicable tool for deriving sequence-based selective inhibitors for a broad range of protein kinases as hits that may be further developed into drugs. Moreover, it enables identification of novel kinase targets for selected therapeutic indications as demonstrated in the KinScreen application.
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Affiliation(s)
- Masha Y Niv
- Keryx Biopharmaceuticals, 15 Yad-Haruzim St., Jerusalem 93420, Israel
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Lu Y, Yu Q, Liu JH, Zhang J, Wang H, Koul D, McMurray JS, Fang X, Yung WKA, Siminovitch KA, Mills GB. Src family protein-tyrosine kinases alter the function of PTEN to regulate phosphatidylinositol 3-kinase/AKT cascades. J Biol Chem 2003; 278:40057-66. [PMID: 12869565 DOI: 10.1074/jbc.m303621200] [Citation(s) in RCA: 199] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Src family protein-tyrosine kinases, which play an important role in signal integration, have been implicated in tumorigenesis in multiple lineages, including breast cancer. We demonstrate, herein, that Src kinases regulate the phosphatidylinositol 3-kinase (PI3K) signaling cascade via altering the function of the PTEN tumor suppressor. Overexpression of activated Src protein-tyrosine kinases in PTEN-deficient breast cancer cells does not alter AKT phosphorylation, an indicator of signal transduction through the PI3K pathway. However, in the presence of functional PTEN, Src reverses the activity of PTEN, resulting in an increase in AKT phosphorylation. Activated Src reduces the ability of PTEN to dephosphorylate phosphatidylinositols in micelles and promotes AKT translocation to cellular plasma membranes but does not alter PTEN activity toward water-soluble phosphatidylinositols. Thus, Src may alter the capacity of the PTEN C2 domain to bind cellular membranes rather than directly interfering with PTEN enzymatic activity. Tyrosine phosphorylation of PTEN is increased in breast cancer cells treated with pervanadate, suggesting that PTEN contains sites for tyrosine phosphorylation. Src kinase inhibitors markedly decreased pervanadate-mediated tyrosine phosphorylation of PTEN. Further, expression of activated Src results in marked tyrosine phosphorylation of PTEN. SHP-1, a SH2 domain-containing protein-tyrosine phosphatase, selectively binds and dephosphorylates PTEN in Src transfected cells. Both Src inhibitors and SHP-1 overexpression reverse Src-induced loss of PTEN function. Coexpression of PTEN with activated Src reduces the stability of PTEN. Taken together, the data indicate that activated Src inhibits PTEN function leading to alterations in signaling through the PI3K/AKT pathway.
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Affiliation(s)
- Yiling Lu
- Department of Molecular Therapeutics, Division of Cancer Medicine, M. D. Anderson Cancer Center, Houston, Texas 77030, USA
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