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Smith LB, Walker WH. The regulation of spermatogenesis by androgens. Semin Cell Dev Biol 2014; 30:2-13. [PMID: 24598768 DOI: 10.1016/j.semcdb.2014.02.012] [Citation(s) in RCA: 485] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 02/20/2014] [Accepted: 02/24/2014] [Indexed: 11/16/2022]
Abstract
Testosterone is essential for maintaining spermatogenesis and male fertility. However, the molecular mechanisms by which testosterone acts have not begun to be revealed until recently. With the advances obtained from the use of transgenic mice lacking or overexpressing the androgen receptor, the cell specific targets of testosterone action as well as the genes and signaling pathways that are regulated by testosterone are being identified. In this review, the critical steps of spermatogenesis that are regulated by testosterone are discussed as well as the intracellular signaling pathways by which testosterone acts. We also review the functional information that has been obtained from the knock out of the androgen receptor from specific cell types in the testis and the genes found to be regulated after altering testosterone levels or androgen receptor expression.
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Affiliation(s)
- Lee B Smith
- MRC Centre for Reproductive Health, University of Edinburgh, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK.
| | - William H Walker
- Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh School of Medicine, 204 Craft Avenue, Pittsburgh, PA 15261, USA.
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Androgens regulate ovarian follicular development by increasing follicle stimulating hormone receptor and microRNA-125b expression. Proc Natl Acad Sci U S A 2014; 111:3008-13. [PMID: 24516121 DOI: 10.1073/pnas.1318978111] [Citation(s) in RCA: 208] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Although androgen excess is considered detrimental to women's health and fertility, global and ovarian granulosa cell-specific androgen-receptor (AR) knockout mouse models have been used to show that androgen actions through ARs are actually necessary for normal ovarian function and female fertility. Here we describe two AR-mediated pathways in granulosa cells that regulate ovarian follicular development and therefore female fertility. First, we show that androgens attenuate follicular atresia through nuclear and extranuclear signaling pathways by enhancing expression of the microRNA (miR) miR-125b, which in turn suppresses proapoptotic protein expression. Second, we demonstrate that, independent of transcription, androgens enhance follicle-stimulating hormone (FSH) receptor expression, which then augments FSH-mediated follicle growth and development. Interestingly, we find that the scaffold molecule paxillin regulates both processes, making it a critical regulator of AR actions in the ovary. Finally, we report that low doses of exogenous androgens enhance gonadotropin-induced ovulation in mice, further demonstrating the critical role that androgens play in follicular development and fertility. These data may explain reported positive effects of androgens on ovulation rates in women with diminished ovarian reserve. Furthermore, this study demonstrates mechanisms that might contribute to the unregulated follicle growth seen in diseases of excess androgens such as polycystic ovary syndrome.
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Abstract
Paxillin is a well-characterized cytoplasmic adaptor protein that is known to play important roles in cytoskeletal rearrangement, cell adhesion, and cell motility. In addition to its structural functions, paxillin has more recently been shown to function as a regulator of cell division-mediating steroid-triggered meiosis in oocytes as well as steroid- and growth factor-induced proliferation in prostate and breast cancer. Paxillin mediates these processes through a conserved pathway that involves both extranuclear (nongenomic) and nuclear (genomic) steroid signaling, as well as both cytoplasmic and nuclear kinase signaling. In fact, paxillin appears to serve as a critical liaison between extranuclear and nuclear signaling in response to multiple stimuli, making it a fascinating molecule to study when trying to determine how growth signals from the membrane lead to important proliferative changes in the nucleus. This chapter outlines recent advances in understanding how paxillin regulates both steroid and growth factor signaling, focusing on the conserved nature of its actions from a frog germ cell to a human cancer cell.
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Affiliation(s)
- Stephen R Hammes
- Division of Endocrinology and Metabolism, Department of Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave., 693, Rochester, NY, 14642, USA,
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Chen DL, Wang ZQ, Ren C, Zeng ZL, Wang DS, Luo HY, Wang F, Qiu MZ, Bai L, Zhang DS, Wang FH, Li YH, Xu RH. Abnormal expression of paxillin correlates with tumor progression and poor survival in patients with gastric cancer. J Transl Med 2013; 11:277. [PMID: 24180516 PMCID: PMC4228400 DOI: 10.1186/1479-5876-11-277] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 10/30/2013] [Indexed: 02/07/2023] Open
Abstract
Background Paxillin (PXN) has been found to be aberrantly regulated in various malignancies and involved in tumor growth and invasion. The clinicopathological and prognostic significance of PXN in gastric cancer is still unclear. Methods The expression of PXN was determined in paired gastric cancer tissues and adjacent normal tissues by Western blotting and real-time PCR. Immunohistochemistry was performed to detect the expression of PXN in 239 gastric cancer patients. Statistical analysis was applied to investigate the correlation between PXN expression and clinicopathological characteristics and prognosis in patients. Additionally, the effects of PXN on gastric cancer cell proliferation and migration were also evaluated. Results PXN was up-regulated in gastric cancer tissues and cell lines as compared with adjacent normal tissues and normal gastric epithelial cell line GES-1. Overexpression of PXN was correlated with distant metastasis (P = 0.001) and advanced tumor stage (P = 0.021) in gastric cancer patients. Patients with high PXN expression tended to have poor prognosis compared with patients with low PXN expression (P < 0.001). Multivariate analysis demonstrated that PXN expression was an independent prognostic factor (P = 0.020). Moreover, ectopic expression of PXN promotes cell proliferation and migration in AGS cells whereas knockdown of PXN inhibits cell proliferation and migration in SGC7901 cells. Conclusions PXN plays an important role in tumor progression and may be used as a potential prognostic indicator in gastric cancer.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Rui-hua Xu
- State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Dong Feng East Road, 510060 Guangzhou, P,R, China.
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Phosphorylation of paxillin confers cisplatin resistance in non-small cell lung cancer via activating ERK-mediated Bcl-2 expression. Oncogene 2013; 33:4385-95. [DOI: 10.1038/onc.2013.389] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 07/05/2013] [Accepted: 08/02/2013] [Indexed: 12/21/2022]
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Yamaguchi S, Komiya S, Matsunuma E, Yamahira S, Kihara T, Miyake J, Nagamune T. Transfer printing of transfected cell microarrays from poly(ethylene glycol)-oleyl surfaces onto biological hydrogels. Biotechnol Bioeng 2013; 110:3269-74. [DOI: 10.1002/bit.25010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 07/13/2013] [Accepted: 07/15/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Satoshi Yamaguchi
- Department of Chemistry and Biotechnology; Graduate School of Engineering; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-8656 Japan
| | - Senori Komiya
- Department of Bioengineering; Graduate School of Engineering; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-8656 Japan
| | - Erika Matsunuma
- Department of Chemistry and Biotechnology; Graduate School of Engineering; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-8656 Japan
| | - Shinya Yamahira
- Department of Bioengineering; Graduate School of Engineering; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-8656 Japan
| | - Takanori Kihara
- Department of Mechanical Science and Bioengineering; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka Japan
| | - Jun Miyake
- Department of Mechanical Science and Bioengineering; Graduate School of Engineering Science; Osaka University; Toyonaka Osaka Japan
| | - Teruyuki Nagamune
- Department of Chemistry and Biotechnology; Graduate School of Engineering; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-8656 Japan
- Department of Bioengineering; Graduate School of Engineering; The University of Tokyo; 7-3-1, Hongo Bunkyo-ku Tokyo 113-8656 Japan
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Shafi AA, Yen AE, Weigel NL. Androgen receptors in hormone-dependent and castration-resistant prostate cancer. Pharmacol Ther 2013; 140:223-38. [PMID: 23859952 DOI: 10.1016/j.pharmthera.2013.07.003] [Citation(s) in RCA: 252] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 06/24/2013] [Indexed: 01/18/2023]
Abstract
In the United States, prostate cancer (PCa) is the most commonly diagnosed non-cutaneous cancer in males and the second leading cause of cancer-related death for men. The prostate is an androgen-dependent organ and PCa is an androgen-dependent disease. Androgen action is mediated by the androgen receptor (AR), a hormone activated transcription factor. The primary treatment for metastatic PCa is androgen deprivation therapy (ADT). For the most part, tumors respond to ADT, but most become resistant to therapy within two years. There is persuasive evidence that castration resistant (also termed castration recurrent) PCa (CRPC) remains AR dependent. Recent studies have shown that there are numerous factors that contribute to AR reactivation despite castrate serum levels of androgens. These include changes in AR expression and structure through gene amplification, mutation, and alternative splicing. Changes in steroid metabolism, cell signaling, and coregulator proteins are also important contributors to AR reactivation in CRPC. Most AR targeted therapies have been directed at the hormone binding domain. The finding that constitutively active AR splice variants that lack the hormone binding domain are frequently expressed in CRPC highlights the need to develop therapies that target other portions of AR. In this review, the role of AR in normal prostate, in PCa, and particularly the mechanisms for its reactivation subsequent to ADT are summarized. In addition, recent clinical trials and novel approaches to target AR are discussed.
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Affiliation(s)
- Ayesha A Shafi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, M515, One Baylor Plaza, Houston, TX 77030, USA
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Lang F, Alevizopoulos K, Stournaras C. Targeting membrane androgen receptors in tumors. Expert Opin Ther Targets 2013; 17:951-63. [PMID: 23746222 DOI: 10.1517/14728222.2013.806491] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION In the last decade androgen actions that are originated from non-genomic, rapid signaling have been described in a large number of cell models and tissues. These effects are initiated through the stimulation of membrane androgen-binding sites or receptors (mAR). Although the molecular identity of mARs remains elusive, their activation is known to trigger multiple non-genomic signaling cascades and to regulate numerous cell responses. In recent years specific interest is being paid to the role of mARs in tumors. Specifically, it was demonstrated that mAR activation by non-permeable testosterone conjugates induced potent anti-tumorigenic responses in prostate, breast, colon and glial tumors. In addition, in vivo animal studies further emphasized the potential clinical importance of these receptors. AREAS COVERED This review will summarize the current knowledge on the mAR-induced non-genomic, rapid androgen actions. It will focus on the molecular signaling pathways governed by mAR activation, discuss latest attempts to elucidate the molecular identity of mAR, address the plethora of cell responses initiated by mAR and evaluate the potential role of mAR and mAR-specific signaling as possible therapeutic targets in tumors. EXPERT OPINION mAR and mAR-induced specific signaling may represent novel therapeutic targets in tumors through the development of specific testosterone analogs.
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Affiliation(s)
- Florian Lang
- University of Tübingen, Department of Physiology, Gmelin Str. 5, Tübingen, 72076, Germany
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59
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Chen DL, Wang DS, Wu WJ, Zeng ZL, Luo HY, Qiu MZ, Ren C, Zhang DS, Wang ZQ, Wang FH, Li YH, Kang TB, Xu RH. Overexpression of paxillin induced by miR-137 suppression promotes tumor progression and metastasis in colorectal cancer. Carcinogenesis 2012; 34:803-11. [PMID: 23275153 PMCID: PMC3616669 DOI: 10.1093/carcin/bgs400] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The deregulation of paxillin (PXN) has been involved in the progression and metastasis of different malignancies including colorectal cancer (CRC). miR-137 is frequently suppressed in CRC. PXN is predicted to be a direct target of miR-137 in CRC cells. On this basis, we hypothesized that overexpression of PXN induced by suppression of miR-137 may promote tumor progression and metastasis and predicts poor prognosis. We detected the expression of PXN and miR-137 in clinical tumor tissues by immunohistochemical analysis and real-time PCR, positive PXN staining was observed in 198 of the 247 (80.1%) cases, whereas no or weak PXN staining was observed in the adjacent non-cancerous area. Higher level of PXN messenger RNA (mRNA) and lower level of miR-137 was observed in cancer tissues than adjacent non-cancerous tissues. High expression of PXN and low expression of miR-137 was associated with aggressive tumor phenotype and adverse prognosis. Moreover, the expression of PXN was negatively correlated with miR-137 expression. A dual-luciferase reporter gene assay validated that PXN was a direct target of miR-137. The use of miR-137 mimics or inhibitor could decrease or increase PXN mRNA and protein levels in CRC cell lines. Knockdown of PXN or ectopic expression of miR-137 could markedly inhibit cell proliferation, migration and invasion in vitro and repress tumor growth and metastasis in vivo. Taken together, these results demonstrated that overexpression of PXN induced by suppression of miR-137 promotes tumor progression and metastasis and could serve as an independent prognostic indicator in CRC patients.
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Tu C, Li J, Bu Y, Hangauer D, Qu J. An ion-current-based, comprehensive and reproducible proteomic strategy for comparative characterization of the cellular responses to novel anti-cancer agents in a prostate cell model. J Proteomics 2012; 77:187-201. [PMID: 22982362 DOI: 10.1016/j.jprot.2012.08.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 08/18/2012] [Accepted: 08/31/2012] [Indexed: 11/18/2022]
Abstract
Proteome-level investigation of the molecular targets in anticancer action of promising pharmaceutical candidates is highly desirable but remains challenging due to the insufficient proteome coverage, limited capacity for biological replicates, and largely unregulated false positive biomarker discovery of current methods. This study described a practical platform strategy to address these challenges, using comparison of drug response proteomic signatures by two promising anti-cancer agents (KX01/KX02) as the model system for method development/optimization. Drug-treated samples were efficiently extracted followed by precipitation/on-pellet-digestion procedure that provides high, reproducible peptide recovery. High-resolution separations were performed on a 75-cm-long, heated nano-LC column with a 7-h gradient, with a highly reproducible nano-LC/nanospray configuration. An LTQ Orbitrap hybrid mass spectrometer with a charge overfilling approach to enhance sensitivity was used for detection. Analytical procedures were optimized and well-controlled to achieve high run-to-run reproducibility that permits numerous replicates in one set, and an ion-current-based approach was utilized for quantification. The false positives of biomarker discovery arising from technical variability was controlled based on FBDR measurement by comparing biomarker numbers in each drug-treated group vs. "sham samples", which were analyzed in an order randomly interleaved with the analysis drug-treated samples. More than 1500 unique protein groups were quantified under stringent criteria, and of which about 30% displayed differential expression with FBDR of 0.3-2.1% across groups. Comparison of drug-response proteomic signatures and the subsequent immunoassay revealed that the action mechanisms of KX01/KX02 are similar but significantly different from vinblastine, which correlates well with clinical and pre-clinical observations. Furthermore, the results strongly supported the hypothesis that KX01/KX02 are dual-action agents (through inhibition of tubulin and Src). Moreover, informative insights into the drug-actions on cell cycle, growth/proliferation, and apoptosis were obtained. This platform technology provides extensive evaluation of drug candidates and facilitates in-depth mechanism studies.
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Affiliation(s)
- Chengjian Tu
- Department of Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14260 USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, 701 Ellicott Street, Buffalo, NY 14203 USA
| | - Jun Li
- Department of Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14260 USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, 701 Ellicott Street, Buffalo, NY 14203 USA
| | - Yahao Bu
- Kinex Pharmaceuticals LLC, New York State Center of Excellence in Bioinformatics and Life Sciences, 701 Ellicott Street, Buffalo, NY 14203 USA
| | - David Hangauer
- Kinex Pharmaceuticals LLC, New York State Center of Excellence in Bioinformatics and Life Sciences, 701 Ellicott Street, Buffalo, NY 14203 USA
| | - Jun Qu
- Department of Pharmaceutical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14260 USA
- New York State Center of Excellence in Bioinformatics and Life Sciences, 701 Ellicott Street, Buffalo, NY 14203 USA
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Yoo SM, Antonyak MA, Cerione RA. The adaptor protein and Arf GTPase-activating protein Cat-1/Git-1 is required for cellular transformation. J Biol Chem 2012; 287:31462-70. [PMID: 22807447 DOI: 10.1074/jbc.m112.353615] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Cat-1/Git-1 is a multifunctional protein that acts as a GTPase-activating protein (GAP) for Arf GTPases, as well as serves as a scaffold for a number of different signaling proteins. Cat-1 is best known for its role in regulating cell shape and promoting cell migration. However, whether Cat-1 might also contribute to cellular transformation is currently unknown. Here we show that ∼95% of cervical tumor samples examined overexpress Cat-1, suggesting that the up-regulation of Cat-1 expression is a frequent occurrence in this type of cancer. We demonstrate further that knocking down Cat-1 from NIH3T3 fibroblasts expressing an activated form of Cdc42 (Cdc42 F28L), or from the human cervical carcinoma (HeLa) cell line, inhibits the ability of these cells to form colonies in soft agar, an in vitro measure of tumorgenicity. The requirement for Cat-1 when assaying the anchorage-independent growth of transformed fibroblasts and HeLa cells is dependent on its ability to bind paxillin, while being negatively impacted by its Arf-GAP activity. Moreover, the co-expression of Cat-1 and an activated form of Arf6 in fibroblasts was sufficient to induce their transformation. These findings highlight novel roles for Cat-1 and its interactions with the Arf GTPases and paxillin in oncogenic transformation.
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Affiliation(s)
- Sungsoo M Yoo
- Department of Molecular Medicine, Cornell University, Ithaca, New York 14853, USA
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Sen A, De Castro I, Defranco DB, Deng FM, Melamed J, Kapur P, Raj GV, Rossi R, Hammes SR. Paxillin mediates extranuclear and intranuclear signaling in prostate cancer proliferation. J Clin Invest 2012; 122:2469-81. [PMID: 22684108 DOI: 10.1172/jci62044] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 05/02/2012] [Indexed: 01/26/2023] Open
Abstract
In prostate cancer, the signals that drive cell proliferation change as tumors progress from castration-sensitive (androgen-dominant) to castration-resistant states. While the mechanisms underlying this change remain uncertain, characterization of common signaling components that regulate both stages of prostate cancer proliferation is important for developing effective treatment strategies. Here, we demonstrate that paxillin, a known cytoplasmic adaptor protein, regulates both androgen- and EGF-induced nuclear signaling. We show that androgen and EGF promoted MAPK-dependent phosphorylation of paxillin, resulting in nuclear translocation of paxillin. We found nuclear paxillin could then associate with androgen-stimulated androgen receptor (AR). This complex bound AR-sensitive promoters, retaining AR within the nucleus and regulating AR-mediated transcription. Nuclear paxillin also complexed with ERK and ELK1, mediating c-FOS and cyclin D1 expression; this was followed by proliferation. Thus, paxillin is a liaison between extranuclear MAPK signaling and nuclear transcription in response to androgens and growth factors, making it a potential regulator of both castration-sensitive and castration-resistant prostate cancer. Accordingly, paxillin was required for normal growth of human prostate cancer cell xenografts, and its expression was elevated in human prostate cancer tissue microarrays. Paxillin is therefore a potential biomarker for prostate cancer proliferation and a possible therapeutic target for prostate cancer treatment.
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Affiliation(s)
- Aritro Sen
- Division of Endocrinology and Metabolism, University of Rochester Medical Center, Rochester, NY, USA
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63
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Lee SH, Hollingsworth R, Kwon HY, Lee N, Chung CY. β-arrestin 2-dependent activation of ERK1/2 is required for ADP-induced paxillin phosphorylation at Ser(83) and microglia chemotaxis. Glia 2012; 60:1366-77. [PMID: 22638989 DOI: 10.1002/glia.22355] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Accepted: 04/25/2012] [Indexed: 12/24/2022]
Abstract
Microglia play crucial roles in increased inflammation in the central nervous system upon brain injuries and diseases. Extracellular ADP has been reported to induce microglia chemotaxis and membrane ruffle formation through P2Y(12) receptor. In this study, we examined the role of ERK1/2 activation in ADP-induced microglia chemotaxis. ADP stimulation increases the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and paxillin phosphorylation at Tyr(31) and Ser(83) . Inhibition of ERK1/2 significantly inhibited paxillin phosphorylation at Ser(83) and the retraction of membrane ruffles, causing inefficient chemotaxis. Close examination of dynamics of focal adhesion (FA) formation with green fluorescent protein-paxillin revealed that the disassembly of FAs in U0126-treated cells was significantly impaired. Depletion of β-Arrestin 2 (β-Arr2) with short hairpin RNA markedly reduced the phosphorylation of ERK1/2 and Pax/Ser(83) , indicating that β-Arr2 is required for ERK1/2 activation upon ADP stimulation. A large fraction of phosphorylated ERK1/2 and β-Arr2 were translocated and co-localized at focal contacts in the newly forming lamellipodia. Examination of kinetics and rate constant of paxillin formation and disassembly revealed that the phosphorylation of paxillin at Tyr(31) by c-Src appears to be involved in adhesion formation upon ADP stimulation while Ser(83) required for adhesion disassembly.
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Affiliation(s)
- Sang-Hyun Lee
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232-6600, USA
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Autocrine CCL2 promotes cell migration and invasion via PKC activation and tyrosine phosphorylation of paxillin in bladder cancer cells. Cytokine 2012; 59:423-32. [PMID: 22617682 DOI: 10.1016/j.cyto.2012.04.017] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 03/27/2012] [Accepted: 04/11/2012] [Indexed: 12/20/2022]
Abstract
The amount of monocyte chemoattractant protein-1 (MCP-1/CCL2) produced by a transitional cell carcinoma is directly correlated with high recurrence and poor prognosis in bladder cancer. However, the mechanisms underlying the effects of CCL2 on tumor progression remain unexplored. To investigate the role played by CCL2, we examined cell migration in various bladder cancer cell lines. We found that high-grade cancer cells expressing high levels of CCL2 showed more migration activity than low-grade bladder cancer cells expressing low levels of the chemokine. Although the activation of CCL2/CCR2 signals did not appreciably affect cell growth, it mediated cell migration and invasion via the activation of protein kinase C and phosphorylation of tyrosine in paxillin. Blocking CCL2 and CCR2 with small hairpin RNA (shCCL2) or a specific inhibitor reduced CCL2/CCR2-mediated cell migration. The antagonist of CCR2 promoted the survival of mice bearing MBT2 bladder cancer cells, and CCL2-depleted cells showed low tumorigenicity compared with shGFP cells. In addition to observing high-levels of CCL2 in high-grade human bladder cancer cells, we showed that the CCL2/CCR2 signaling pathway mediated migratory and invasive activity, whereas blocking the pathway decreased migration and invasion. In conclusion, high levels of CCL2 expressed in bladder cancer mediates tumor invasion and is involved with advanced tumorigenesis. Our findings suggest that this CCL2/CCR2 pathway is a potential candidate for the attenuation of bladder cancer metastases.
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Chakraborty SK, Basu NK, Jana S, Basu M, Raychoudhuri A, Owens IS. Protein kinase Cα and Src kinase support human prostate-distributed dihydrotestosterone-metabolizing UDP-glucuronosyltransferase 2B15 activity. J Biol Chem 2012; 287:24387-96. [PMID: 22532564 DOI: 10.1074/jbc.m111.335067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Because human prostate-distributed UDP-glucuronosyltransferase (UGT) 2B15 metabolizes 5α-dihydrotestosterone (DHT) and 3α-androstane-5α,17β-diol metabolite, we sought to determine whether 2B15 requires regulated phosphorylation similar to UGTs already analyzed. Reversible down-regulation of 2B15-transfected COS-1 cells following curcumin treatment and irreversible inhibition by calphostin C, bisindolylmaleimide, or röttlerin treatment versus activation by phorbol 12-myristate 13-acetate indicated that 2B15 undergoes PKC phosphorylation. Mutation of three predicted PKC and two tyrosine kinase sites in 2B15 caused 70-100 and 80-90% inactivation, respectively. Anti-UGT-1168 antibody trapped 2B15-His-containing co-immunoprecipitates of PKCα in 130-140- and >150-kDa complexes by gradient SDS-PAGE analysis. Complexes bound to WT 2B15-His remained intact during electrophoresis, whereas 2B15-His mutants at phosphorylation sites differentially dissociated. PKCα siRNA treatment inactivated >50% of COS-1 cell-expressed 2B15. In contrast, treatment of 2B15-transfected COS-1 cells with the Src-specific activator 1,25-dihydroxyvitamin D(3) enhanced activity; treatment with the Src-specific PP2 inhibitor or Src siRNA inhibited >50% of the activity. Solubilized 2B15-His-transfected Src-free fibroblasts subjected to in vitro [γ-(33)P]ATP-dependent phosphorylation by PKCα and/or Src, affinity purification, and SDS gel analysis revealed 2-fold more radiolabeling of 55-58-kDa 2B15-His by PKCα than by Src; labeling was additive for combined kinases. Collectively, the evidence indicates that 2B15 requires regulated phosphorylation by both PKCα and Src, which is consistent with the complexity of synthesis and metabolism of its major substrate, DHT. Whether basal cells import or synthesize testosterone for transport to luminal cells for reduction to DHT by 5α-steroid reductase 2, comparatively low-activity luminal cell 2B15 undergoes a complex pattern of regulated phosphorylation necessary to maintain homeostatic DHT levels to support occupation of the androgen receptor for prostate-specific functions.
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Affiliation(s)
- Sunit K Chakraborty
- Section on Genetic Disorders of Drug Metabolism, Program on Developmental Endocrinology and Genetics, NICHD, National Institutes of Health, Bethesda, Maryland 20892-1830, USA
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Vetterkind S, Saphirstein RJ, Morgan KG. Stimulus-specific activation and actin dependency of distinct, spatially separated ERK1/2 fractions in A7r5 smooth muscle cells. PLoS One 2012; 7:e30409. [PMID: 22363435 PMCID: PMC3283592 DOI: 10.1371/journal.pone.0030409] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 12/15/2011] [Indexed: 12/16/2022] Open
Abstract
A proliferative response of smooth muscle cells to activation of extracellular signal regulated kinases 1 and 2 (ERK1/2) has been linked to cardiovascular disease. In fully differentiated smooth muscle, however, ERK1/2 activation can also regulate contraction. Here, we use A7r5 smooth muscle cells, stimulated with 12-deoxyphorbol 13-isobutylate 20-acetate (DPBA) to induce cytoskeletal remodeling or fetal calf serum (FCS) to induce proliferation, to identify factors that determine the outcomes of ERK1/2 activation in smooth muscle. Knock down experiments, immunoprecipitation and proximity ligation assays show that the ERK1/2 scaffold caveolin-1 mediates ERK1/2 activation in response to DPBA, but not FCS, and that ERK1/2 is released from caveolin-1 upon DPBA, but not FCS, stimulation. Conversely, ERK1/2 associated with the actin cytoskeleton is significantly reduced after FCS, but not DPBA stimulation, as determined by Triton X fractionation. Furthermore, cytochalasin treatment inhibits DPBA, but not FCS-induced ERK1/2 phosphorylation, indicating that the actin cytoskeleton is not only a target but also is required for ERK1/2 activation. Our results show that (1) at least two ERK1/2 fractions are regulated separately by specific stimuli, and that (2) the association of ERK1/2 with the actin cytoskeleton regulates the outcome of ERK1/2 signaling.
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Affiliation(s)
- Susanne Vetterkind
- Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America.
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67
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Freeman MR, Yang W, Di Vizio D. Caveolin-1 and prostate cancer progression. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 729:95-110. [PMID: 22411316 DOI: 10.1007/978-1-4614-1222-9_7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
Caveolin-1 was identified in the 1990s as a marker of aggressive prostate cancer. The caveolin-1 protein localizes to vesicular structures called caveolae and has been shown to bind and regulate many signaling proteins involved in oncogenesis. Caveolin-1 also has lipid binding properties and mediates aspects of cholesterol and fatty acid metabolism and can elicit biological responses in a paracrine manner when secreted. Caveolin-1 is also present in the serum of prostate cancer patients and circulating levels correlate with extent of disease. Current evidence indicates that increased expression of caveolin-1 in prostate adenocarcinoma cells and commensurate downregulation of the protein in prostate stroma, mediate progression to the castration-resistant phase of prostate cancer through diverse pathways. This chapter summarizes the current state of our understanding of the cellular and physiologic mechanisms in which caveolin-1 participates in the evolution of prostate cancer cell phenotypes.
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68
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Abstract
The participation of extranuclear steroid receptor signaling in organ physiology and the impact for pathobiology has increasingly been demonstrated. Important functions of membrane estrogen receptors in the cardiovascular system demonstrate new mechanisms of rapid steroid signaling to gene regulation, preventing cardiovascular disease and maintaining healthy arterial function. In cancer cells, kinase signaling initiated by extranuclear estrogen, progesterone, and androgen receptors modulates transcriptional events in the nucleus, which in turn regulate proliferation, migration, and invasion. Important mediators of cross talk between cytoplasmic and nuclear steroid receptor signaling are the proline-, glutamic acid-, and leucine-rich protein-1 and paxillin proteins, both of which modulate membrane and nuclear receptor pool signaling to promote a variety of cell biological functions.
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Affiliation(s)
- Stephen R Hammes
- Department of Medicine, University of Rochester, Rochester, New York 14642, USA.
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69
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Kim JW, Moon DG. Diagnosis and treatment of sexual dysfunctions in late-onset hypogonadism. Korean J Urol 2011; 52:725-35. [PMID: 22195260 PMCID: PMC3242984 DOI: 10.4111/kju.2011.52.11.725] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 09/28/2011] [Indexed: 12/30/2022] Open
Abstract
Testosterone is the principal androgen in the human male. The decline of testosterone with aging was recognized to be associated with a number of symptoms and signs that reduce the quality of life and that may even have severe, debilitating consequences. Clinically, late-onset hypogonadism (LOH) is diagnosed by use of biochemical and clinical measures. Despite published guidelines and recommendations, however, uncertainty surrounds the profile of clinical symptoms as well as the biochemical threshold of diagnosis. Clinicians should be aware of these shortcomings while adhering to the guidelines. Current treatment methods are centered on restoring testosterone to mid to lower levels of young men with natural testosterone replacements. Although recent studies have highlighted possible additional benefits involving improvement of systemic disorders, the goal of treatment is to improve sexual function, while observing for adverse effects in the prostate. Overall, the problem of LOH in debilitating the quality of life and well-being is real, and by following proper guidelines with attentiveness to the results of treatment trials, testosterone replacement therapy presents a safe and effective treatment option.
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Affiliation(s)
- Jin Wook Kim
- Department of Urology, Korea University College of Medicine, Korea University Institute for Regenerative Medicine, Seoul, Korea
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70
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Obinata D, Takayama KI, Urano T, Murata T, Ikeda K, Horie-Inoue K, Ouchi Y, Takahashi S, Inoue S. ARFGAP3, an androgen target gene, promotes prostate cancer cell proliferation and migration. Int J Cancer 2011; 130:2240-8. [PMID: 21647875 DOI: 10.1002/ijc.26224] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2011] [Accepted: 05/23/2011] [Indexed: 01/04/2023]
Abstract
ADP ribosylation factor GTPase-activating protein 3 (ARFGAP3) is a GTPase-activating protein that associates with the Golgi apparatus and regulates the vesicular trafficking pathway. In the present study, we examined the contribution of ARFGAP3 to prostate cancer cell biology. We showed that ARFGAP3 expression was induced by 100 nM of dihydrotestosterone (DHT) at both the mRNA and protein levels in androgen-sensitive LNCaP cells. We generated stable transfectants of LNCaP cells with FLAG-tagged ARFGAP3 or a control empty vector and showed that ARFGAP3 overexpression promoted cell proliferation and migration compared with control cells. We found that ARFGAP3 interacted with paxillin, a focal adhesion adaptor protein that is important for cell mobility and migration. Small interfering RNA (siRNA)-mediated knockdown of ARFGAP3 showed that ARFGAP3 siRNA markedly reduced LNCaP cell growth. Androgen receptor (AR)-dependent transactivation activity on prostate-specific antigen (PSA) enhancer was synergistically promoted by exogenous ARFGAP3 and paxillin expression, as shown by luciferase assay in LNCaP cells. Thus, our results suggest that ARFGAP3 is a novel androgen-regulated gene that can promote prostate cancer cell proliferation and migration in collaboration with paxillin.
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Affiliation(s)
- Daisuke Obinata
- Department of Anti-Aging Medicine, The University of Tokyo, Tokyo, Japan
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71
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Sen A, Prizant H, Hammes SR. Understanding extranuclear (nongenomic) androgen signaling: what a frog oocyte can tell us about human biology. Steroids 2011; 76:822-8. [PMID: 21354434 PMCID: PMC4972037 DOI: 10.1016/j.steroids.2011.02.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 01/13/2011] [Accepted: 02/16/2011] [Indexed: 12/13/2022]
Abstract
Steroids are key factors in a myriad of mammalian biological systems, including the brain, kidney, heart, bones, and gonads. While alternative potential steroid receptors have been described, the majority of biologically relevant steroid responses appear to be mediated by classical steroid receptors that are located in all parts of the cell, from the plasma membrane to the nucleus. Interestingly, these classical steroid receptors modulate different signals depending upon their location. For example, receptors in the plasma membrane interact with membrane signaling molecules, including G proteins and kinases. In contrast, receptors in the nucleus interact with nuclear signaling molecules, including transcriptional co-regulators. These extranuclear and intranuclear signals function together in an integrated fashion to regulate important biological functions. While most studies on extranuclear steroid signaling have focused on estrogens, recent work has demonstrated that nongenomic androgen signaling is equally important and that these two steroids modulate similar signaling pathways. In fact, by taking advantage of a simple model system whereby a physiologically relevant androgen-mediated process is regulated completely independent of transcription (Xenopus laevis oocyte maturation), many novel and conserved concepts in nongenomic steroid signaling have been uncovered and characterized.
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Affiliation(s)
| | | | - Stephen R Hammes
- Corresponding author: Stephen R Hammes, M.D., Ph.D., Division of Endocrinology and Metabolism, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave. Rochester, NY 14642. Phone: 585-275-2901; Fax: 585-273-1288;
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72
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Wang X, Stewart PA, Cao Q, Sang QXA, Chung LWK, Emmett MR, Marshall AG. Characterization of the phosphoproteome in androgen-repressed human prostate cancer cells by Fourier transform ion cyclotron resonance mass spectrometry. J Proteome Res 2011; 10:3920-8. [PMID: 21786837 DOI: 10.1021/pr2000144] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Androgen-repressed human prostate cancer, ARCaP, grows and is highly metastatic to bone and soft tissues in castrated mice. The molecular mechanisms underlying the aberrant responses to androgen are not fully understood. Here, we apply state-of-the-art mass spectrometry methods to investigate the phosphoproteome profiles in ARCaP cells. Because protein biological phosphorylation is always substoichiometric and the ionization efficiency of phosphopeptides is low, selective enrichment of phosphorylated proteins/peptides is required for mass spectrometric analysis of phosphorylation from complex biological samples. Therefore, we compare the sensitivity, efficiency, and specificity for three established enrichment strategies: calcium phosphate precipitation (CPP), immobilized metal ion affinity chromatography (IMAC), and TiO(2)-modified metal oxide chromatography. Calcium phosphate precipitation coupled with the TiO(2) approach offers the best strategy to characterize phosphorylation in ARCaP cells. We analyzed phosphopeptides from ARCaP cells by LC-MS/MS with a hybrid LTQ/FT-ICR mass spectrometer. After database search and stringent filtering, we identified 385 phosphoproteins with an average peptide mass error of 0.32 ± 0.6 ppm. Key identified oncogenic pathways include the mammalian target of rapamycin (mTOR) pathway and the E2F signaling pathway. Androgen-induced proliferation inhibitor (APRIN) was detected in its phosphorylated form, implicating a molecular mechanism underlying the ARCaP phenotype.
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Affiliation(s)
- Xu Wang
- Department of Chemistry and Biochemistry, 95 Chieftain Way, Florida State University, Tallahassee, Florida 32306, United States
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73
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Carbajal L, Biswas A, Niswander LM, Prizant H, Hammes SR. GPCR/EGFR cross talk is conserved in gonadal and adrenal steroidogenesis but is uniquely regulated by matrix metalloproteinases 2 and 9 in the ovary. Mol Endocrinol 2011; 25:1055-65. [PMID: 21454403 DOI: 10.1210/me.2010-0410] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Previous work has demonstrated that cross talk between G protein-coupled LH receptors and epidermal growth factor receptors (EGFR) is essential for LH-induced steroid production in ovarian follicles and testicular Leydig cells. Here we demonstrate that G protein-coupled receptor (GPCR)/EGFR cross talk is also required for ACTH-induced steroidogenesis in Y1 adrenal cells. Moreover, we confirm that the signaling pathway from GPCR to Erk activation is conserved in all three steroidogenic tissues. ACTH or LH induces Gα(s), resulting in elevated cAMP and protein kinase A activation. cAMP/protein kinase A then triggers EGFR trans-activation, which promotes Erk signaling and subsequent steroidogenesis. Interestingly, although EGFR trans-activation is conserved in all three tissues, the specific mechanisms regulating this receptor cross talk differ. ACTH and LH trigger matrix metalloproteinase (MMP)-mediated release of EGFR ligands in adrenal and gonadal cells, respectively. However, this extracellular, ligand-dependent EGFR transactivation is required only for LH-induced steroidogenesis in ovarian follicles, reflecting the unique requirement of cell-cell cross talk for ovarian steroid production. Furthermore, MMP2 and MMP9 appear to regulate LH-induced steroidogenesis in mouse ovarian follicles, because a specific MMP2/9 inhibitor as well as the MMP2/9 inhibitor doxycycline suppress LH-induced follicular steroid production in vitro. Notably, although EGFR or MMP inhibition minimally affects estrous cycling in female mice, they attenuate ovarian steroidogenesis in response to LHR overstimulation in vivo. These results may have implications with regard to EGFR inhibitor use in various cancers as well as in polycystic ovarian syndrome, where excess LH-driven ovarian androgen production might be controlled by MMP2/9 inhibition.
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Affiliation(s)
- Liliana Carbajal
- Division of Endocrinology and Metabolism, Department of Medicine, University of Rochester Medical Center, Rochester, New York 14642, USA
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74
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Desiniotis A, Kyprianou N. Significance of talin in cancer progression and metastasis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2011; 289:117-47. [PMID: 21749900 DOI: 10.1016/b978-0-12-386039-2.00004-3] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Upon detachment from the extracellular matrix, tumor epithelial cells and tumor-associated endothelial cells are capable of overcoming anoikis, gain survival benefits, and hence contribute to the process of metastasis. The focal-adhesion complex formation recruits the association of key adaptor proteins such as FAK (focal-adhesion kinase). Vimentin, paxillin, and talin are responsible for mediating the interaction between the actin cytoskeleton and integrins. Talin is an early-recruited focal-adhesion player that is of structural and functional significance in mediating interactions with integrin cytoplasmic tails leading to destabilization of the transmembrane complex and resulting in rearrangements in the extracellular integrin compartments that mediate integrin activation. Talin-mediated integrin activation plays a definitive role in integrin-mediated signaling and induction of downstream survival pathways leading to protection from anoikis and consequently resulting in cancer progression to metastasis. We recently reported that talin expression is significantly increased in prostate cancer compared with benign and normal prostate tissue and that this overexpression correlates with progression to metastatic disease implicating a prognostic value for talin during tumor progression. At the molecular level, talin is functionally associated with enhanced survival and proliferation pathways and confers anoikis resistance and metastatic spread of primary tumor cells via activation of the Akt survival pathway. In this review, we discuss the growing evidence surrounding the value of talin as a prognostic marker of cancer progression to metastasis and as therapeutic target in advanced prostate cancer, as well as the current understanding of mechanisms regulating its signaling activity in cancer.
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Affiliation(s)
- Andreas Desiniotis
- Department of Surgery/Urology, and Department of Molecular and Cellular Biochemistry, University of Kentucky College of Medicine, Lexington, USA
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75
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Levin ER. Minireview: Extranuclear steroid receptors: roles in modulation of cell functions. Mol Endocrinol 2010; 25:377-84. [PMID: 20861220 DOI: 10.1210/me.2010-0284] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Steroid receptors existing outside the nucleus are increasingly being recognized in many organs and cell types, impacting the biology of bone, the heart and blood vessels, and the central nervous system. Some controversy exists as to the nature of the receptors at the plasma membrane. However, compelling evidence has been advanced that at least some classical steroid receptors mediate steroid ligand actions originating as signaling from the cell surface. Here I review the recent findings in this evolving field emphasizing the in vivo impact of these receptor pools with a focus on estrogen receptors.
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Affiliation(s)
- Ellis R Levin
- Division of Endocrinology, Department of Veterans Affairs Medical Center, Long Beach, California 90822, USA.
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