1
|
Xia H, Zhan Y, Wang L, Wang X. Exploring the interplay between circadian rhythms and prostate cancer: insights into androgen receptor signaling and therapeutic opportunities. Front Cell Dev Biol 2024; 12:1421204. [PMID: 39011396 PMCID: PMC11246886 DOI: 10.3389/fcell.2024.1421204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 06/11/2024] [Indexed: 07/17/2024] Open
Abstract
Circadian rhythm disruption is closely related to increased incidence of prostate cancer. Incorporating circadian rhythms into the study of prostate cancer pathogenesis can provide a more comprehensive understanding of the causes of cancer and offer new options for precise treatment. Therefore, this article comprehensively summarizes the epidemiology of prostate cancer, expounds the contradictory relationship between circadian rhythm disorders and prostate cancer risk, and elucidates the relationship between circadian rhythm regulators and the incidence of prostate cancer. Importantly, this article also focuses on the correlation between circadian rhythms and androgen receptor signaling pathways, as well as the applicability of time therapy in prostate cancer. This may prove significant in enhancing the clinical treatment of prostate cancer.
Collapse
Affiliation(s)
- Hongyan Xia
- College of Basic Medical Sciences, Shanxi Medical University, Taiyuan, China
| | - Yang Zhan
- National Engineering Laboratory for AIDS Vaccine, College of Life Sciences, Jilin University, Changchun, China
| | - Li Wang
- Department of Pathology, Shanxi Medical University, Taiyuan, China
| | - Xiaohui Wang
- Department of Pathology, Shanxi Medical University, Taiyuan, China
| |
Collapse
|
2
|
Ibtisham F, Cham TC, Fayaz MA, Honaramooz A. Effects of Growth Factors on In Vitro Culture of Neonatal Piglet Testicular Tissue Fragments. Cells 2023; 12:2234. [PMID: 37759457 PMCID: PMC10526381 DOI: 10.3390/cells12182234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/25/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
In vitro spermatogenesis (IVS) has important applications including fertility preservation of prepubertal cancer patients; however, thus far, IVS has only been achieved using mouse models. To study the effects of growth factors on the maintenance of testicular tissue integrity, germ cell numbers, and potential induction of IVS using a porcine model, we cultured small testicular fragments (~2 mg) from 1-wk-old piglets under six different media conditions (DMEM + 10%KSR alone or supplemented with GDNF, bFGF, SCF, EGF, or a combination of all) for 8 weeks. Overall, tissues supplemented with GDNF and bFGF had the greatest seminiferous tubule integrity and least number of apoptotic cells. GDNF-supplemented tissues had the greatest number of gonocytes per tubule, followed by bFGF-supplemented tissues. There was evidence of gradual Sertoli cell maturation in all groups. Moreover, histological examination and the expression of c-KIT (a marker of differentiating spermatogonia and spermatocytes) and STRA8 (a marker of the pre/meiotic stage germ cells) confirmed the induction of IVS in all groups. However, GDNF- and bFGF-supplemented tissue cultures had greater numbers of seminiferous tubules with spermatocytes compared to other groups. In conclusion, overall, GDNF and bFGF supplementation better maintained the tissue integrity and gonocyte numbers and induced IVS in cultured testicular tissues.
Collapse
Affiliation(s)
| | | | | | - Ali Honaramooz
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada; (F.I.); (T.-C.C.); (M.A.F.)
| |
Collapse
|
3
|
The Effect of Testosterone on Cardiovascular Disease and Cardiovascular Risk Factors in Men: A Review of Clinical and Preclinical Data. CJC Open 2021; 3:1238-1248. [PMID: 34888506 PMCID: PMC8636244 DOI: 10.1016/j.cjco.2021.05.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 05/09/2021] [Indexed: 11/20/2022] Open
Abstract
Cardiovascular disease (CVD) is the leading cause of death worldwide. The effects of testosterone, the primary male sex hormone, on cardiovascular risk have been of special interest due to the increased risk of CVD in men. Although it is well established that testosterone levels decline and cardiovascular mortality increases with age, the association between testosterone and CVD remains unclear. Observational and randomized studies on the effects of endogenous and exogenous testosterone have produced conflicting data, and meta-analyses have been inconclusive, suggesting significant study heterogeneity. Despite a lack of adequately powered randomized controlled trials, large observational studies in the early 2010s led to advisories on the use of testosterone replacement therapy. Similar advisories have been mandated for certain types of androgen deprivation therapy. Additional research suggests that testosterone shortens the heart-rate-corrected QT interval, improves glycemic control, induces vasodilation, is prothrombotic, and has anti-obesity effects, whereas associations with atherosclerosis and inflammation are less clear. Despite inconclusive evidence on cardiovascular risk and inconsistencies among clinical practice guidelines, millions of men continue to use testosterone replacement and androgen deprivation therapy. In addition to summarizing clinical and preclinical data, this review provides insight on potential mechanisms of action of testosterone on CVD, applications of this knowledge to clinical settings, and avenues for future research.
Collapse
|
4
|
Annual reproductive cycle of males of the bat Molossus molossus: Seasonal bimodal polyestry, testicular regression, and some aspects of the hormonal control. Theriogenology 2020; 158:297-308. [DOI: 10.1016/j.theriogenology.2020.09.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/14/2020] [Accepted: 09/17/2020] [Indexed: 11/21/2022]
|
5
|
Akinola LK, Uzairu A, Shallangwa GA, Abechi SE. Theoretical study on endocrine disrupting effects of polychlorinated dibenzo‐
p
‐dioxins using molecular docking simulation. J Appl Toxicol 2020; 41:233-246. [DOI: 10.1002/jat.4039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/24/2020] [Accepted: 06/24/2020] [Indexed: 12/25/2022]
Affiliation(s)
- Lukman K. Akinola
- Department of Chemistry Ahmadu Bello University Zaria Nigeria
- Department of Chemistry Bauchi State University Gadau Nigeria
| | - Adamu Uzairu
- Department of Chemistry Ahmadu Bello University Zaria Nigeria
| | | | | |
Collapse
|
6
|
Lee HS, Jung DW, Han S, Kang HS, Suh JH, Oh HS, Hwang MS, Moon G, Park Y, Hong JH, Koo YE. Veterinary drug, 17β-trenbolone promotes the proliferation of human prostate cancer cell line through the Akt/AR signaling pathway. CHEMOSPHERE 2018; 198:364-369. [PMID: 29421751 DOI: 10.1016/j.chemosphere.2018.01.145] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 01/08/2018] [Accepted: 01/27/2018] [Indexed: 06/08/2023]
Abstract
Trenbolone acetate (TBA) is a synthetic anabolic steroidal growth factor that is used for rapid muscle development in cattle. The absorbed TBA is hydrolyzed to the active form, 17β-trenbolone (17 TB; 17β-hydroxy-estra-4,9,11-trien-3-one) in meat and milk products, which can cause adverse health effects in humans. Similar to 5α-dihydrotestosterone (DHT), 17 TB was reported to exhibit endocrine disrupting effects on animals and humans due to its androgenic effect via binding to the androgen receptor. The purpose of this study is to investigate the molecular mechanism of cell proliferation in prostate cancer (PCa) cells treated with 17 TB. We found that 17 TB induces AR-dependent cell proliferation in the human prostate cancer cell line, 22Rv1 in a concentration dependent manner. Treatment with 17 TB increased the expression of cell cycle regulatory proteins, cyclin D2/CDK-4 and cyclin E/CDK-2, whereas the expression of p27 was down-regulated. Furthermore, phosphorylation of Rb and activation of E2F were also induced, which suggests the activation of cyclin D2/CDK-4 and cyclin E/CDK-2 in the cells. When 22Rv1 cells were exposed to 30 pM of 17 TB, which is the effective concentration (EC50) value required to observe proliferative effects on 22Rv1 cells, the expression levels of the phosphorylated forms of Akt and GSK3β were increased. This study demonstrates that 17 TB induces AR-dependent proliferation through the modulation of cell cycle-related proteins in the Akt signaling pathway. The present study provides an effective methodology for identifying cell proliferation signaling of veterinary drugs that exert AR agonistic effects.
Collapse
Affiliation(s)
- Hee-Seok Lee
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea.
| | - Da-Woon Jung
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Songyi Han
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Hui-Seung Kang
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Jin-Hyang Suh
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Hyun-Suk Oh
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Myung-Sil Hwang
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Guiim Moon
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Yooheon Park
- Dongguk University Research Institute of Biotechnology & Medical Converged Science, Dongguk University, Gyeonggi 10325, Republic of Korea
| | - Jin-Hwan Hong
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea
| | - Yong Eui Koo
- National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 28159, Republic of Korea.
| |
Collapse
|
7
|
Jiang Z, Zhou B, Li X, Kirby GM, Zhang X. Echinacoside Increases Sperm Quantity in Rats by Targeting the Hypothalamic Androgen Receptor. Sci Rep 2018; 8:3839. [PMID: 29497114 PMCID: PMC5832853 DOI: 10.1038/s41598-018-22211-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 02/19/2018] [Indexed: 01/11/2023] Open
Abstract
Male infertility is a major health issue with an estimated prevalence of 4.2% of male infertility worldwide. Our early work demonstrated that Cistanche extracts protect against sperm damage in mice and that echinacoside (ECH) is one of the major active components. Here we report an essential role for ECH, a natural product that reverses or protects against oligoasthenospermia in rats. ECH was assayed by HPLC, the quantity and quality of sperm was evaluated and hormone levels were determined by radioimmunosorbent assay. ECH reduced levels of androgen receptor (AR) and key steroidogenic-related genes as determined by Western blot and qPCR analysis. The interaction between ECH and AR were evaluated by indirect ELISA and molecular docking. The results show that ECH combined with hypothalamic AR in the pocket of Met-894 and Val-713 to inhibit transfer of AR from the cytoplasm to nuclei in the hypothalamus. While negative feedback of sex hormone regulation was inhibited, positive feedback was stimulated to increase the secretion of luteinizing hormone and testosterone subsequently enhancing the quantity of sperm. Taken together, these data demonstrate that ECH blocks AR activity in the hypothalamus to increase the quantity of sperm and protect against oligoasthenospermia in rats.
Collapse
Affiliation(s)
- Zhihui Jiang
- Research Center of Modern Biotechnology, School of Biotechnology and Food Engineering, Anyang Institute of Technology, Anyang, Henan, 455000, China.,College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi, 712100, China
| | - Bo Zhou
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi, 712100, China
| | - Xinping Li
- College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi, 712100, China
| | - Gordon M Kirby
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
| | - Xiaoying Zhang
- Research Center of Modern Biotechnology, School of Biotechnology and Food Engineering, Anyang Institute of Technology, Anyang, Henan, 455000, China. .,College of Veterinary Medicine, Northwest A & F University, Yangling, Shaanxi, 712100, China.
| |
Collapse
|
8
|
Masoodi KZ, Eisermann K, Yang Z, Dar JA, Pascal LE, Nguyen M, O’Malley K, Parrinello E, Feturi FG, Kenefake AN, Nelson JB, Johnston PA, Wipf P, Wang Z. Inhibition of Androgen Receptor Function and Level in Castration-Resistant Prostate Cancer Cells by 2-[(isoxazol-4-ylmethyl)thio]-1-(4-phenylpiperazin-1-yl)ethanone. Endocrinology 2017; 158:3152-3161. [PMID: 28977599 PMCID: PMC5659684 DOI: 10.1210/en.2017-00408] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 07/17/2017] [Indexed: 02/08/2023]
Abstract
The androgen receptor (AR) plays a critical role in the development of castration-resistant prostate cancer (CRPC) as well as in the resistance to the second-generation AR antagonist enzalutamide and the selective inhibitor of cytochrome P450 17A1 (CYP17A1) abiraterone. Novel agents targeting AR may inhibit the growth of prostate cancer cells resistant to enzalutamide and/or abiraterone. Through a high-throughput/high-content screening of a 220,000-member small molecule library, we have previously identified 2-[(isoxazol-4-ylmethyl)thio]-1-(4-phenylpiperazin-1-yl)ethanone (IMTPPE) (SID 3712502) as a novel small molecule capable of inhibiting AR transcriptional activity and protein level in C4-2 prostate cancer cells. In this study, we show that IMTPPE inhibits AR-target gene expression using real-time polymerase chain reaction, Western blot, and luciferase assays. IMTPPE inhibited proliferation of AR-positive, but not AR-negative, prostate cancer cells in culture. IMTPPE inhibited the transcriptional activity of a mutant AR lacking the ligand-binding domain (LBD), indicating that IMTPPE inhibition of AR is independent of the LBD. Furthermore, animal studies showed that IMTPPE inhibited the growth of 22Rv1 xenograft tumor, a model for enzalutamide-resistant prostate cancer. These findings suggest that IMTPPE is a potential lead compound for developing clinical candidates for the treatment of CRPC, including those resistant to enzalutamide.
Collapse
Affiliation(s)
- Khalid Z. Masoodi
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Transcriptomics Laboratory, Division of Plant Biotechnology, SKUAST-Kashmir, Shalimar, Srinagar, Jammu and Kashmir 190025, India
| | - Kurtis Eisermann
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Department of Biological Sciences, Kent State University, Kent, Ohio 44242
| | - Zhenyu Yang
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Department of Urology, The Third Xiangya Hospital, Central South University, Changsha, 410013 Hunan, People’s Republic of China
| | - Javid A. Dar
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Central Laboratory College of Science, King Saud University, Riyadh KSA-11451, Saudi Arabia
| | - Laura E. Pascal
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Minh Nguyen
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Katherine O’Malley
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Erica Parrinello
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Firuz G. Feturi
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania 15232
| | - Alex N. Kenefake
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Joel B. Nelson
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Paul A. Johnston
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania 15232
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| | - Peter Wipf
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh, Pennsylvania 15232
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Zhou Wang
- Department of Urology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15232
| |
Collapse
|
9
|
Wang T, Qu X, Jiang J, Gao P, Zhao D, Lian X, Li X. Diagnostic significance of urinary long non-coding PCA3 RNA in prostate cancer. Oncotarget 2017; 8:58577-58586. [PMID: 28938580 PMCID: PMC5601676 DOI: 10.18632/oncotarget.17272] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 03/31/2017] [Indexed: 12/19/2022] Open
Abstract
Prostate cancer antigen 3(PCA3) is a long non-coding RNA, which was found increased expression in CaP patients than healthy individual. In this study, the individual nucleic acid of PCA3 and PSA was recombinant expressed as a reference reagent, and a quantitative RT-PCR with TaqMan assay was developed to examine the copies of PCA3 and PSA gene in urine. The results showed that the area under the receiver operating characteristic curve (AUROC) was 0.717, 0.444 and 0.916 for the number of PCA3 copy, PSA copy and for the score of PCA3/PSA RNA, respectively. Additionally, the AUROC for serum tPSA was 0.674 with a low specificity of 12.07%. Finally, the algorithm of PCA3 RNA versus PSA RNA was evaluated and corroborated as CaP biomarker by conducting a multicentric clinical trial. This study not only validated the developed technique of qRT-PCR with TaqMan assay for examination of urinary PCA3 and PSA RNA, it also demonstrated that the score of the PCA/PSA RNA was a reliable signature for CaP diagnosis.
Collapse
Affiliation(s)
- Tao Wang
- Key Laboratory of PreMed Precision Medicine, Soochow University, Suzhou, 215121, China.,Jiangsu Provincial Key Laboratory of Molecular Biology and Translational Medicine of Malignant Tumor, Suzhou, 215123, China
| | - Xiangyun Qu
- Key Laboratory of PreMed Precision Medicine, Soochow University, Suzhou, 215121, China
| | - Jiajia Jiang
- Affiliated AoYang Hospital of Jiangsu University, Zhangjiagang, Suzhou, 215600, China
| | - Peng Gao
- Key Laboratory of PreMed Precision Medicine, Soochow University, Suzhou, 215121, China
| | - Dingding Zhao
- Key Laboratory of PreMed Precision Medicine, Soochow University, Suzhou, 215121, China
| | - Xueqi Lian
- Affiliated AoYang Hospital of Jiangsu University, Zhangjiagang, Suzhou, 215600, China
| | - Xiaohua Li
- Affiliated AoYang Hospital of Jiangsu University, Zhangjiagang, Suzhou, 215600, China.,Nanjing Medical University, Nanjing, 211166, China
| |
Collapse
|
10
|
Chandrasekar T, Yang JC, Gao AC, Evans CP. Mechanisms of resistance in castration-resistant prostate cancer (CRPC). Transl Androl Urol 2016; 4:365-80. [PMID: 26814148 PMCID: PMC4708226 DOI: 10.3978/j.issn.2223-4683.2015.05.02] [Citation(s) in RCA: 217] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Despite advances in prostate cancer diagnosis and management, morbidity from prostate cancer remains high. Approximately 20% of men present with advanced or metastatic disease, while 29,000 men continue to die of prostate cancer each year. Androgen deprivation therapy (ADT) has been the standard of care for initial management of advanced or metastatic prostate cancer since Huggins and Hodges first introduced the concept of androgen-dependence in 1972, but progression to castration-resistant prostate cancer (CRPC) occurs within 2-3 years of initiation of ADT. CRPC, previously defined as hormone-refractory prostate cancer, is now understood to still be androgen dependent. Multiple mechanisms of resistance help contribute to the progression to castration resistant disease, and the androgen receptor (AR) remains an important driver in this progression. These mechanisms include AR amplification and hypersensitivity, AR mutations leading to promiscuity, mutations in coactivators/corepressors, androgen-independent AR activation, and intratumoral and alternative androgen production. More recently, identification of AR variants (ARVs) has been established as another mechanism of progression to CRPC. Docetaxel chemotherapy has historically been the first-line treatment for CRPC, but in recent years, newer agents have been introduced that target some of these mechanisms of resistance, thereby providing additional survival benefit. These include AR signaling inhibitors such as enzalutamide (Xtandi, ENZA, MDV-3100) and CYP17A1 inhibitors such as abiraterone acetate (Zytiga). Ultimately, these agents will also fail to suppress CRPC. While some of the mechanisms by which these agents fail are unique, many share similarities to the mechanisms contributing to CRPC progression. Understanding these mechanisms of resistance to ADT and currently approved CRPC treatments will help guide future research into targeted therapies.
Collapse
Affiliation(s)
| | - Joy C Yang
- Department of Urology, University of California, Davis, CA, USA
| | - Allen C Gao
- Department of Urology, University of California, Davis, CA, USA
| | | |
Collapse
|
11
|
Xu X, Chen X, Hu H, Dailey AB, Odedina FT. WITHDRAWN: Current opinion in the role of testosterone in the development of prostate cancer: A dynamic model. Med Hypotheses 2016. [DOI: 10.1016/j.mehy.2015.12.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
12
|
Xu X, Chen X, Hu H, Dailey AB, Taylor BD. Current opinion on the role of testosterone in the development of prostate cancer: a dynamic model. BMC Cancer 2015; 15:806. [PMID: 26502956 PMCID: PMC4623905 DOI: 10.1186/s12885-015-1833-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 10/19/2015] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Since the landmark study conducted by Huggins and Hodges in 1941, a failure to distinguish between the role of testosterone in prostate cancer development and progression has led to the prevailing opinion that high levels of testosterone increase the risk of prostate cancer. To date, this claim remains unproven. PRESENTATION OF THE HYPOTHESIS We present a novel dynamic mode of the relationship between testosterone and prostate cancer by hypothesizing that the magnitude of age-related declines in testosterone, rather than a static level of testosterone measured at a single point, may trigger and promote the development of prostate cancer. TESTING THE HYPOTHESIS Although not easily testable currently, prospective cohort studies with population-representative samples and repeated measurements of testosterone or retrospective cohorts with stored blood samples from different ages are warranted in future to test the hypothesis. IMPLICATIONS OF THE HYPOTHESIS Our dynamic model can satisfactorily explain the observed age patterns of prostate cancer incidence, the apparent conflicts in epidemiological findings on testosterone and risk of prostate cancer, racial disparities in prostate cancer incidence, risk factors associated with prostate cancer, and the role of testosterone in prostate cancer progression. Our dynamic model may also have implications for testosterone replacement therapy.
Collapse
Affiliation(s)
- Xiaohui Xu
- Department of Epidemiology & Biostatistics, School of Public Health, Texas A&M Health Science Center, 205A SRPH Administration Building | MS 1266, 212 Adriance Lab Road, College Station, TX, 77843-1266, USA.
| | - Xinguang Chen
- Department of Epidemiology, College of Public Health and Health Professions and College of Medicine, University of Florida, Gainesville, FL, USA.
| | - Hui Hu
- Department of Epidemiology, College of Public Health and Health Professions and College of Medicine, University of Florida, Gainesville, FL, USA.
| | - Amy B Dailey
- Health Sciences Department, Gettysburg College, Gettysburg, PA, USA.
| | - Brandie D Taylor
- Department of Epidemiology & Biostatistics, School of Public Health, Texas A&M Health Science Center, 205A SRPH Administration Building | MS 1266, 212 Adriance Lab Road, College Station, TX, 77843-1266, USA.
| |
Collapse
|
13
|
Chandrasekar T, Yang JC, Gao AC, Evans CP. Targeting molecular resistance in castration-resistant prostate cancer. BMC Med 2015; 13:206. [PMID: 26329698 PMCID: PMC4556222 DOI: 10.1186/s12916-015-0457-6] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 08/19/2015] [Indexed: 12/20/2022] Open
Abstract
Multiple mechanisms of resistance contribute to the inevitable progression of hormone-sensitive prostate cancer to castration-resistant prostate cancer (CRPC). Currently approved therapies for CRPC include systemic chemotherapy (docetaxel and cabazitaxel) and agents targeting the resistance pathways leading to CRPC, including enzalutamide and abiraterone. While there is significant survival benefit, primary and secondary resistance to these therapies develops rapidly. Up to one-third of patients have primary resistance to enzalutamide and abiraterone; the remaining patients eventually progress on treatment. Understanding the mechanisms of resistance resulting in progression as well as identifying new targetable pathways remains the focus of current prostate cancer research. We review current knowledge of mechanisms of resistance to the currently approved treatments, development of adjunctive therapies, and identification of new pathways being targeted for therapeutic purposes.
Collapse
Affiliation(s)
| | - Joy C Yang
- Department of Urology, University of California, Davis, USA.
| | - Allen C Gao
- Department of Urology, University of California, Davis, USA.
| | - Christopher P Evans
- Department of Urology, University of California, Davis, USA. .,, 4860 Y Street, Suite 3500, Sacramento, CA, 95817, USA.
| |
Collapse
|
14
|
Non-classical testosterone signaling is mediated by a G-protein-coupled receptor interacting with Gnα11. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:1172-81. [DOI: 10.1016/j.bbamcr.2014.03.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 02/28/2014] [Accepted: 03/01/2014] [Indexed: 01/26/2023]
|
15
|
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: 249] [Impact Index Per Article: 22.6] [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.
Collapse
Affiliation(s)
- Ayesha A Shafi
- Department of Molecular and Cellular Biology, Baylor College of Medicine, M515, One Baylor Plaza, Houston, TX 77030, USA
| | | | | |
Collapse
|
16
|
Alves MG, Rato L, Carvalho RA, Moreira PI, Socorro S, Oliveira PF. Hormonal control of Sertoli cell metabolism regulates spermatogenesis. Cell Mol Life Sci 2013; 70:777-93. [PMID: 23011766 PMCID: PMC11113727 DOI: 10.1007/s00018-012-1079-1] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 06/11/2012] [Accepted: 06/26/2012] [Indexed: 11/30/2022]
Abstract
Hormonal regulation is essential to spermatogenesis. Sertoli cells (SCs) have functions that reach far beyond the physical support of germ cells, as they are responsible for creating the adequate ionic and metabolic environment for germ cell development. Thus, much attention has been given to the metabolic functioning of SCs. During spermatogenesis, germ cells are provided with suitable metabolic substrates, in a set of events mediated by SCs. Multiple signaling cascades regulate SC function and several of these signaling pathways are hormone-dependent and cell-specific. Within the seminiferous tubules, only SCs possess receptors for some hormones rendering them major targets for the hormonal signaling that regulates spermatogenesis. Although the mechanisms by which SCs fulfill their own and germ cells metabolic needs are mostly studied in vitro, SC metabolism is unquestionably a regulation point for germ cell development and the hormonal control of these processes is required for a normal spermatogenesis.
Collapse
Affiliation(s)
- Marco G. Alves
- CICS-UBI, Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Luís Rato
- CICS-UBI, Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Rui A. Carvalho
- CNC-UC, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
- Department of Life Sciences, Faculty of Science and Technology (FCTUC), University of Coimbra, 3004-517 Coimbra, Portugal
| | - Paula I. Moreira
- CNC-UC, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
- Institute of Physiology, Faculty of Medicine, University of Coimbra, 3000-354 Coimbra, Portugal
| | - Sílvia Socorro
- CICS-UBI, Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| | - Pedro F. Oliveira
- CICS-UBI, Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal
| |
Collapse
|
17
|
Lorenzetti F, Pintarelli VL, Seraphim DCC, Dambros M. Low testosterone levels induce apoptosis via active 3-caspase dependent signaling in the bladder wall of male rats. Aging Male 2012; 15:216-9. [PMID: 22967305 DOI: 10.3109/13685538.2012.716876] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE The bladder can be considered a target organ for testosterone action, and low testosterone levels possibly cause damage to bladder cells. We set out to study whether hypoandrogenism influences bladder wall cell damage in castrated and senile male rats. METHODS Thirty male Wistar rats were divided into three groups of 10 animals each: group I (3 months old), sham animals; group II (27 months old), senile animals; group III (3 months old), subjected to bilateral orchiectomy, and sacrificed 8 weeks after the procedure. Bladders were excised, weighed and sent for analysis. Stereological assays on collagen fibers and immunohistochemical analysis with active 3-caspase were performed on bladder cells. RESULTS Bladder weights were greater in the senile group than in the others. Stereological collagen fiber analysis demonstrated higher density in group III than in groups I and II (p < 0.05). The absolute density was 4.15 mm(3) in group I, 22.3 mm(3) in group II and 19.3 mm(3) in group III. Semiquantitative active 3-caspase analysis showed greater percentages in the senile group II than in groups I and III. CONCLUSIONS We can state that low plasma testosterone levels are related to higher collagen fiber density and active 3-caspase percentages in the bladder walls of orchiectomized and senile rats, respectively.
Collapse
Affiliation(s)
- Fábio Lorenzetti
- Department of Geriatric Urology, Federal University of São Paulo, São Paulo, SP, Brazil
| | | | | | | |
Collapse
|
18
|
Tarulli GA, Stanton PG, Meachem SJ. Is the adult Sertoli cell terminally differentiated? Biol Reprod 2012; 87:13, 1-11. [PMID: 22492971 DOI: 10.1095/biolreprod.111.095091] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
New data have challenged the convention that the adult Sertoli cell population is fixed and unmodifiable. The Sertoli cell has two distinct functions: 1) formation of the seminiferous cords and 2) provision of nutritional and structural support to developing germ cells. For these to occur successfully, Sertoli cells must undergo many maturational changes between fetal and adult life, the main switches occurring around puberty, including the loss of proliferative activity and the formation of the blood-testis barrier. Follicle-stimulating hormone plays a key role in promoting Sertoli cell proliferation, while thyroid hormone inhibits proliferative activity in early postnatal life. Together these regulate the Sertoli-germ cell complement and sperm output in adulthood. By puberty, the Sertoli cell population is considered to be stable and unmodifiable by hormones. But there is mounting evidence that the size of the adult Sertoli cell population and its maturational status is modifiable by hormones and that Sertoli cells can gain proliferative ability in the spermatogenically disrupted hamster and human model. This new information demonstrates that the adult Sertoli cell population, at least in the settings of testicular regression in the hamster and impaired fertility in humans in vivo and from mice and men in vitro, is not a terminally differentiated population. Data from the hamster now show that the adult Sertoli cell population size is regulated by hormones. This creates exciting prospects for basic and clinical research in testis biology. The potential to replenish an adult Sertoli-germ cell complement to normal in a setting of infertility may now be realized.
Collapse
Affiliation(s)
- Gerard A Tarulli
- Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia
| | | | | |
Collapse
|
19
|
Abdelbaqi K, Lack N, Guns ET, Kotha L, Safe S, Sanderson JT. Antiandrogenic and growth inhibitory effects of ring-substituted analogs of 3,3'-diindolylmethane (ring-DIMs) in hormone-responsive LNCaP human prostate cancer cells. Prostate 2011; 71:1401-12. [PMID: 21321979 DOI: 10.1002/pros.21356] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 01/14/2011] [Indexed: 11/09/2022]
Abstract
BACKGROUND Cruciferous vegetables protect against prostate cancer. Indole-3-carbinol (I3C) and its major metabolite 3,3'-diindolylmethane (DIM), exhibit antitumor activities in vitro and in vivo. Several synthetic ring-substituted dihaloDIMs (ring-DIMs) appear to have increased anticancer activity. METHODS Inhibition of LNCaP prostate cancer cell growth was measured by a WST-1 cell viability assay. Cytoplasmic and nuclear proteins were analyzed by immunoblotting and immunofluorescence. Androgen receptor (AR) activation was assessed by measuring prostate-specific antigen (PSA) expression and using LNCaP cells containing human AR and an AR-dependent probasin promoter-green fluorescent protein (GFP) construct. RESULTS Like DIM, several ring-substituted dihaloDIM analogs, namely 4,4'-dibromo-, 4,4'-dichloro-, 7,7'-dibromo-, and 7,7'-dichloroDIM, significantly inhibited DHT-stimulated growth of LNCaP cells at concentrations ≥1 µM. We observed structure-dependent differences for the effects of the ring-DIMs on AR expression, nuclear AR accumulation and PSA levels in LNCaP cells after 24 hr. Both 4,4'- and 7,7'-dibromoDIM decreased AR protein and mRNA levels, whereas 4,4'- and 7,7'-dichloroDIM had minimal effect. All four dihaloDIMs (10 and 30 µM) significantly decreased PSA protein and mRNA levels. Immuofluorescence studies showed that only the dibromoDIMs increased nuclear localization of AR. All ring-DIMs caused a concentration-dependent decrease in fluorescence induced by the synthetic androgen R1881 in LNCaP cells transfected with wild-type human AR and an androgen-responsive probasin promoter-GFP gene construct, with potencies up to 10-fold greater than that of DIM. CONCLUSION The antiandrogenic effects of ring-DIMs suggest they may form the basis for the development of novel agents against hormone-sensitive prostate cancer, alone or in combination with other drugs.
Collapse
Affiliation(s)
- Khalil Abdelbaqi
- INRS-Institut Armand-Frappier, Université du Québec, Laval, QC, Canada
| | | | | | | | | | | |
Collapse
|
20
|
Yu JJ, Jiang YC. Association of testicular p63 expression and spermatogenesis in androgen receptor knockout (ARKO) mice. Aging Male 2011; 14:72-5. [PMID: 20670103 DOI: 10.3109/13685538.2010.487922] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To study changes of testicular p63 expression and its effect on spermatogenic function in seminiferous tubules in androgen receptor knockout (ARKO) mice. METHODS A total of 28 ARKO mice (ARKO group) screened by Cre-lox and 28 male Wistar mice without ARKO (controlled group) were enrolled in our study. Route pathology was performed and p63 examination was detected by immunohistochemistry in testes. Linear correlations were used to explore potential associations between p63 protein expression and spermatogenic function (TMS score). RESULTS In ARKO group, inner diameter of seminiferous tubules was decreased (62 +/- 1.3 microm vs. 91 +/- 1.2 microm), thickness of the basal membrane of the tubules (4 +/- 0.3 microm vs. 2.7 +/- 0.5 microm), cellular population within tubules was reduced (2 +/- 0.4 vs. 4 +/- 0.1 layers), degree of spermatogenesis within the tubules turned to disturbance (3 +/- 1.0 vs. 5 +/- 0.1), Testicular Makler score was lower than controlled group (7 +/- 0.2 vs.15 +/- 0.3), they had significant differences (p <0.01). P63 expressed significantly lower in ARKO group than that in Wistar group, and was limited at stages from spermatocyte to round spermatid. (Percentage of positive cells ? 68.1 +/- 3.7 vs. 81.7 +/- 5.1, p<0.001). The HSCORE yielded similar results (HSCORE 3.7 +/- 0.3 vs. 2.0 +/- 0.2, p<0.001). p63 protein expression was significantly positively correlated with spermatogenic function (r=0.87, p<0.01). CONCLUSIONS p63 developed important effect on spermatogenesis and the regulatory effect of p63 on spermatogenesis mainly occurred in the early stage of spermiogenesis in testis.
Collapse
Affiliation(s)
- Jian Jun Yu
- Shang Hai 6th People's Hospital, Shang Hai Jiaotong University, Shang Hai 200233, China.
| | | |
Collapse
|
21
|
Deep G, Gangar SC, Oberlies NH, Kroll DJ, Agarwal R. Isosilybin A induces apoptosis in human prostate cancer cells via targeting Akt, NF-κB, and androgen receptor signaling. Mol Carcinog 2010; 49:902-12. [PMID: 20721970 DOI: 10.1002/mc.20670] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Prostate cancer (PCA) is the second most malignancy in American men. Advanced stage PCA cells possess unlimited replication potential as well as resistance to apoptosis. Therefore, targeting survival mechanisms and activating apoptotic machinery in PCA cells using nontoxic phytochemicals is suggested as an attractive strategy against this deadly malignancy. In the present study, we assessed the effect of one such botanical agent, namely isosilybin A, on apoptotic machinery and key members of cell survival signaling [Akt, NF-κB, and androgen receptor (AR)] in different PCA cells. Results showed that isosilybin A (90-180 µM) treatment significantly induces apoptotic death by activating both extrinsic (increased level of DR5 and cleaved caspase 8) and intrinsic pathways (caspase 9 and 3 activation) of apoptosis in three different human PCA cell lines namely 22Rv1, LAPC4, and LNCaP. Further, isosilybin A treatment decreased the levels of phospho-Akt (serine-473), total Akt, and the nuclear levels of NF-κB constituents (p50 and p65). Isosilybin A treatment also decreased the AR and PSA level in 22Rv1, LAPC4, and LNCaP cells. Employing pan-caspase inhibitor (Z-VAD.fmk), we confirmed that isosilybin A-mediated decreased AR is independent of caspases activation. Temporal kinetics analysis showed that the primary effect of isosilybin A is on AR, as decrease in AR was evident much earlier (4 h) relative to caspase activation and apoptosis induction (12 h). Overall, our results demonstrated that isosilybin A activates apoptotic machinery in PCA cells via targeting Akt-NF-κB-AR axis; thereby, indicating a promising role for this phytochemical in the management of clinical PCA.
Collapse
Affiliation(s)
- Gagan Deep
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver, Aurora, Colorado, USA
| | | | | | | | | |
Collapse
|
22
|
Wang G, Pan Y, Ahmad KA, Ahmed K. Protein B23/nucleophosmin/numatrin nuclear dynamics in relation to protein kinase CK2 and apoptotic activity in prostate cells. Biochemistry 2010; 49:3842-52. [PMID: 20387789 DOI: 10.1021/bi9021928] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Protein B23/nucleophosmin/numatrin (B23) is a key nucleolar/nuclear matrix-associated protein required for cell growth-related functions, such as rRNA synthesis. Protein kinase CK2 (CK2) (formerly casein kinase 2, a protein Ser/Thr kinase signal that is involved in cell growth and cell death) mediates phosphorylation of B23, thereby influencing its functional activity. Here we have delineated the dynamics of B23 and its link to CK2 status in response to altered growth stimuli and induction of apoptosis in cultured prostate cells and in rat prostate cells in vivo. Our studies employing PC-3 and ALVA-41 prostate cancer cells demonstrated colocalization of CK2 and B23 in the nucleus. Further, CK2 and B23 underwent coordinate modulation in the nucleus related to their nucleocytoplasmic shuttling in response to induction of apoptotic activity in cells caused by downregulation of CK2 or by treatment with other apoptosis-inducing agents. These alterations in nuclear association of B23 occurred in the absence of a significant change in the level of cytoplasmic B23. Similar studies in the in vivo model of rat prostate epithelial cells subjected to androgen deprivation (that resulted in loss of nuclear CK2 and induction of apoptosis) demonstrated dynamic modulation of nuclear matrix-associated B23 without a significant change in its cytoplasmic level. These changes were reversed by androgen-mediated growth response in the prostate. Our results suggest that CK2-mediated phosphorylation of B23 is essential for its retention in the nucleus and that coordinated nuclear localization of B23 and CK2 is dynamically regulated in response to altered growth status in the cell.
Collapse
Affiliation(s)
- Guixia Wang
- Cellular and Molecular Biochemistry Research Laboratory (151), Minneapolis Veterans Affairs Medical Center, and Department of Laboratory Medicine and Pathology and Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55417, USA
| | | | | | | |
Collapse
|
23
|
Schulze JJ, Rane A, Ekström L. Genetic variation in androgen disposition: implications in clinical medicine including testosterone abuse. Expert Opin Drug Metab Toxicol 2010; 5:731-44. [PMID: 19442030 DOI: 10.1517/17425250902976862] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Testosterone replacement therapy in hypogonadal men has been used for > 60 years. The use of testosterone substitution is continuously growing and is given to aging men to improve the quality of life. Because testosterone use is associated with muscle strength enhancing effects, it has become a popular drug to abuse. Doping with anabolic steroids, such as testosterone, is a severe challenge to the vision, moral and ethics in sports and has also become a significant and increasing problem in society. OBJECTIVE The primary aim of this review is to summarize and discuss the contribution of genetic components to inter-individual variation in androgen disposition. CONCLUSION Genetic variation has a large impact on androgen disposition. This variation is of the utmost importance for the interpretation of doping test results and may modulate the effects of testosterone replacement therapy and testosterone doping.
Collapse
Affiliation(s)
- Jenny J Schulze
- Karolinska Institutet, Division of Clinical Pharmacology, Stockholm, Sweden
| | | | | |
Collapse
|
24
|
Terada N, Shimizu Y, Yoshida T, Maeno A, Kamba T, Inoue T, Nakamura E, Kamoto T, Ogawa O. Antiandrogen withdrawal syndrome and alternative antiandrogen therapy associated with the W741C mutant androgen receptor in a novel prostate cancer xenograft. Prostate 2010; 70:252-61. [PMID: 19790238 DOI: 10.1002/pros.21058] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND The mechanisms underlying antiandrogen withdrawal syndrome (AWS) and alternative antiandrogen therapy (AAT) effectiveness were assumed to be mutations in the androgen receptor (AR), which resulted in an altered response to antiandrogens. The aim of the present study was to test this assumption using the novel prostate cancer xenograft model KUCaP-1 harboring the W741C mutant AR (Yoshida et al., Cancer Res 2005; 65(21): 9611-9616). METHODS Mice bearing xenograft tumors were castrated, and the long-term sequential changes in tumor volume were observed. To determine whether AWS was observed in this model, bicalutamide (BCL) was orally administered to the castrated mice and then withdrawn. The effect of flutamide (FLT) on the W741C mutant AR was examined with transactivation assays in vitro and with the oral administration of FLT to non-castrated mice harboring KUCaP-1 in vivo. The AAT efficacy against KUCaP-1 was evaluated by changing BCL with FLT. RESULTS KUCaP-1 regressed significantly after castration and did not re-grow. KUCaP-1 treated with BCL continued to grow even after castration and started regressing 2 months after BCL withdrawal, replicating clinically recognized AWS. The antagonistic effect of FLT against the W741C mutant AR was revealed in vitro and in vivo. AAT with FLT suppressed tumor growth after BCL withdrawal. CONCLUSIONS KUCaP-1 was an entirely androgen-dependent xenograft and mimicked the clinical phenomena of AWS and AAT caused by the agonistic and antagonistic activity of BCL and FLT, respectively. KUCaP-1 could be an in vivo model for screening novel antiandrogens for the treatment of BCL resistant prostate cancer harboring the W741C mutation in the AR.
Collapse
Affiliation(s)
- Naoki Terada
- Department of Urology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
25
|
The Role of the Leydig Cell in Spermatogenic Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 636:255-69. [DOI: 10.1007/978-0-387-09597-4_14] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
26
|
Battista N, Rapino C, Di Tommaso M, Bari M, Pasquariello N, Maccarrone M. Regulation of male fertility by the endocannabinoid system. Mol Cell Endocrinol 2008; 286:S17-23. [PMID: 18328619 DOI: 10.1016/j.mce.2008.01.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 01/16/2008] [Accepted: 01/16/2008] [Indexed: 10/22/2022]
Abstract
Mammalian conception is a complex process regulated by both sexual behavior and reproductive performance. Alcohol, marijuana and tobacco are among the main factors which affect negatively fertility in women and men. Several studies have demonstrated that marijuana impairs the male copulatory activity, and that smokers of this illegal drug show reduced fertility due, for instance, to decrease in sperm concentration, defective sperm function or alteration of sperm morphology. The discovery of endocannabinoids and all components responsible for their metabolism has allowed to collect valuable information on the effects of these endogenous lipids, able to mimic the actions of delta-9-tetrahydrocannabinol (THC), in reproductive functions. The purpose of this review is to describe the actions of cannabinoids and endocannabinoids on the control of procreation and hormonal release during the fertilization process in males.
Collapse
Affiliation(s)
- Natalia Battista
- Department of Biomedical Sciences, University of Teramo, Teramo, Italy
| | | | | | | | | | | |
Collapse
|
27
|
Androgen receptor is expressed in both X- and Y-carrier human spermatozoa. Fertil Steril 2008; 91:193-200. [PMID: 18321498 DOI: 10.1016/j.fertnstert.2007.11.040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2007] [Revised: 11/14/2007] [Accepted: 11/14/2007] [Indexed: 01/25/2023]
Abstract
OBJECTIVE To quantify the amount of AR messenger RNA (mRNA) and to analyze the presence and functionality of the AR protein in X- and Y-carrier human spermatozoa. DESIGN A molecular and cellular research study. SETTING Academic research clinic and laboratories. PATIENT(S) Ten normozoospermic volunteers. INTERVENTION(S) Sperm were analyzed for expression of AR mRNA and protein. The functionality of AR protein was assessed after incubation with 1 nM of synthetic androgen. MAIN OUTCOME MEASURE(S) Reverse-transcription polymerase chain reaction (PCR), real-time PCR, Western immunoblotting, confocal immunofluorescence, and fluorescence in situ hybridization analysis were performed. RESULT(S) A significant amount of AR mRNA (around 30% of that found in the testis) was found in sperm. Androgen receptor protein was found in both X- and Y-carrier spermatozoa and translocates into the nucleus in the presence of synthetic androgen. CONCLUSION(S) A functional AR is expressed in human sperm. In view of the fact that AR protein is found in both X- and Y-carrier spermatozoa, it most probably is translated in earlier steps of spermatogenesis and moves to Y-carrier spermatids through the cytoplasmic bridges.
Collapse
|
28
|
Inoue T, Kobayashi T, Terada N, Shimizu Y, Kamoto T, Ogawa O, Nakamura E. Roles of androgen-dependent and -independent activation of signal transduction pathways for cell proliferation of prostate cancer cells. Expert Rev Endocrinol Metab 2007; 2:689-704. [PMID: 30736131 DOI: 10.1586/17446651.2.5.689] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Prostate cancer is one of the most frequently diagnosed cancers in the western world and this malignant neoplasm is the second-leading cause of cancer death among men in the USA. In the early 1940s, Huggins and Hodges demonstrated that growth and survival of prostate cancer depends on androgens. The mainstay of treatment for advanced prostate cancer is currently androgen ablation. Over the past few decades, several compounds, such as luteinizing hormone-releasing hormone analogues and anti-androgens, were developed and widely used in clinics. Then, the new treatment strategy, maximum androgen blockade (MAB) was introduced. In fact, MAB improved the prognosis of patients with advanced prostate cancer to some extent; however, most of those patients finally relapse after a period of initial response to this therapy, developing androgen-independent prostate cancer (AIPC). Once patients develop AIPC, effective therapeutic modalities are extremely limited and, therefore, the prognosis of this disease is very poor. It is strongly desirable to explore novel therapeutic concepts for AIPC, based on detailed molecular mechanisms for progression to androgen independency. As for the molecular mechanisms involved in the emergence of AIPC, mutations in the androgen receptor have been examined most extensively. These days, evidence is accumulating that demonstrates activation of signal transduction pathways, such as Src, PI3K and mTOR/S6K, are involved in the acquisition of the androgen-independent cell proliferation of prostate cancer cells. In addition, animal models using transgenic and gene-knockout techniques have confirmed these results. The development of therapies targeting against the signal transduction pathways is critical for the improvement of the prognosis of patients with AIPC. In this article, we review recent understandings on molecular mechanisms of androgen-dependent proliferation of prostate cancer cells, whose aberrant activation is proposed as a critical event for progression to AIPC.
Collapse
Affiliation(s)
- Takahiro Inoue
- a Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Takashi Kobayashi
- b Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Naoki Terada
- c Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Yosuke Shimizu
- d Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Toshiyuki Kamoto
- e Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Osamu Ogawa
- f Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Eijiro Nakamura
- g Department of Urology, University Graduate School of Medicine, Kyoto, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| |
Collapse
|
29
|
Jarzabek K, Philibert P, Koda M, Sulkowski S, Kotula-Balak M, Bilinska B, Kottler ML, Wolczynski S, Sultan C. Primary amenorrhea in a young Polish woman with complete androgen insensitivity syndrome and Sertoli-Leydig cell tumor: identification of a new androgen receptor gene mutation and evidence of aromatase hyperactivity and apoptosis dysregulation within the tumor. Gynecol Endocrinol 2007; 23:499-504. [PMID: 17852420 DOI: 10.1080/09513590701553852] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Primary amenorrhea in 46,XY females can be due to complete androgen insensitivity syndrome (CAIS), pure gonadal dysgenesis, 17-hydroxysteroid dehydrogenase deficiency, or mixed gonadal dysgenesis. The present paper describes a new de novo non-sense mutation in exon 1 (K141Z) of the androgen receptor gene (AR) and the expression in CAIS testis of aromatase, estrogen receptors, as well as proliferation- and apoptosis-associated proteins. CAIS is a rare disease characterized by absent virilization in 46,XY individuals and the development of a female phenotype despite normal or even elevated androgen levels. CAIS is usually caused by a mutation in AR, which leads to organ resistance to androgens. Testicular tumors such as Sertoli-Leydig cell tumor often develop in patients with CAIS. The immunohistochemical findings in the testes of our CAIS patient suggest that the high expression of aromatase and other molecular changes in the testis may be responsible for pubertal breast development and the increased risk of testicular tumor.
Collapse
Affiliation(s)
- Katarzyna Jarzabek
- Department of Reproduction and Gynaecological Endocrinology, Medical University of Bialystok, Bialystok, Poland
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Heterogeneous nuclear ribonucleoprotein A/B and G inhibits the transcription of gonadotropin-releasing-hormone 1. Mol Cell Neurosci 2007; 37:69-84. [PMID: 17920292 DOI: 10.1016/j.mcn.2007.08.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2006] [Revised: 08/14/2007] [Accepted: 08/21/2007] [Indexed: 12/16/2022] Open
Abstract
Gonadotropin-releasing hormone 1 (GnRH1) causes the release of gonadotropins from the pituitary to control reproduction. Here we report that two heterogeneous nuclear ribonucleoproteins (hnRNP-A/B and hnRNP-G) bind to the GnRH-I upstream promoter region in a cichlid fish Astatotilapia burtoni. We identified these binding proteins using a newly developed homology based method of mass spectrometric peptide mapping. We show that both hnRNP-A/B and hnRNP-G co-localize with GnRH1 in the pre-optic area of the hypothalamus in the brain. We also demonstrated that these ribonucleoproteins exhibit similar binding capacity in vivo, using immortalized mouse GT1-7 cells where overexpression of either hnRNP-A/B or hnRNP-G significantly down-regulates GnRH1 mRNA levels in GT1-7 cells, suggesting that both act as repressors in GnRH1 transcriptional regulation.
Collapse
|
31
|
Li C, Taneda S, Suzuki AK, Furuta C, Watanabe G, Taya K. Anti-androgenic activity of 3-methyl-4-nitrophenol in diesel exhaust particles. Eur J Pharmacol 2006; 543:194-9. [PMID: 16822498 DOI: 10.1016/j.ejphar.2006.06.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2006] [Revised: 05/21/2006] [Accepted: 06/06/2006] [Indexed: 10/24/2022]
Abstract
In our continuing studies on nitrophenol derivatives as vasodilators in diesel exhaust particles, we have reported that nitrophenols in diesel exhaust particles possess not only vasodilatory activity but also estrogenic activity in vitro and in vivo, as well as anti-androgenic activity in vitro. Our efforts here were focused on the in vitro and in vivo anti-androgenic activity of 3-methyl-4-nitrophenol (4-nitro-m-cresol; PNMC), known a degradation product of the insecticide fenitrothion, in diesel exhaust particles. We investigated its anti-androgenic activity using an in vitro recombinant yeast screen and in vivo Hershberger assays. Recombinant yeast screen assay showed that PNMC possesses anti-androgenic activity at low concentrations. Furthermore, castrated 28-day-old immature male rats each implanted with a 5-mm-long silastic tube containing crystalline testosterone and injected with PNMC subcutaneously at doses from as low as 0.01 and 0.1 mg/kg up to 1 mg/kg for 5 consecutive days showed significantly decreased weights of the seminal vesicles, ventral prostate, and glans penis. Plasma follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were significantly increased in the 0.1 mg/kg PNMC treatment group. Our results demonstrate that PNMC in diesel exhaust particles clearly has anti-androgenic activity both in vitro and in vivo and can therefore be considered as an endocrine-disrupting chemical.
Collapse
Affiliation(s)
- ChunMei Li
- Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu 501-1193, Japan
| | | | | | | | | | | |
Collapse
|
32
|
Zheng Z, Cai C, Omwancha J, Chen SY, Baslan T, Shemshedini L. SUMO-3 Enhances Androgen Receptor Transcriptional Activity through a Sumoylation-independent Mechanism in Prostate Cancer Cells. J Biol Chem 2006; 281:4002-12. [PMID: 16361251 DOI: 10.1074/jbc.m509260200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Androgens are important for male sexual development, which depend on the cognate receptor, the androgen receptor. The transcriptional activity of the androgen receptor, like other nuclear receptors, is regulated by accessory proteins that can have either positive or negative effects. Through a yeast functional screen, we have identified SUMO-3 as a regulator of androgen receptor activity in prostate cancer cells. SUMO-3 is one of three eukaryotic proteins that become post-translationally conjugated to their target proteins in a manner analogous to the attachment of ubiquitin. In primary prostate epithelial cells, PrEC, and the prostate cancer cells, PC-3, SUMO-3 has a weak negative effect on androgen receptor transcriptional activity. In contrast, SUMO-3 and it close relative SUMO-2 strongly enhance transactivation by endogenous androgen receptor in LNCaP cells. This positive effect is observed in both androgen-dependent and androgen-independent LNCaP cells. Interestingly, SUMO-1, unlike SUMO-3 and SUMO-2, can inhibit, but not stimulate, androgen receptor activity. Mutational analysis of the androgen receptor and SUMO-3 demonstrates that the SUMO-3-positive activity does not depend on either the sumoylation sites of the androgen receptor or the sumoylation function of SUMO-3. Stable overexpression of SUMO-3 in LNCaP cells significantly enhances the androgen-dependent proliferation of these cells. Additionally, siRNA-mediated repression of SUMO-2 significantly inhibits the growth of both androgen-dependent and -independent LNCaP cells. Collectively, these results suggest (i) a novel mechanism for elevating AR activity through the switch of SUMO-3 from a weak negative regulator in normal prostate cells to a strong positive regulator in prostate cancer cells and (ii) a proliferative role for SUMO-3 and SUMO-2 in the growth of prostate cancer cells that is independent of sumoylation of the androgen receptor.
Collapse
Affiliation(s)
- Zhe Zheng
- University of Toledo, Department of Biological Sciences, OH 43606, USA
| | | | | | | | | | | |
Collapse
|
33
|
Yoshida T, Kinoshita H, Segawa T, Nakamura E, Inoue T, Shimizu Y, Kamoto T, Ogawa O. Antiandrogen bicalutamide promotes tumor growth in a novel androgen-dependent prostate cancer xenograft model derived from a bicalutamide-treated patient. Cancer Res 2005; 65:9611-6. [PMID: 16266977 DOI: 10.1158/0008-5472.can-05-0817] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Androgen ablation therapies are effective in controlling prostate cancer. Although most cancers relapse and progress despite androgen ablation, some patients experience antiandrogen withdrawal syndrome, in which those treated with antiandrogen show clinical improvement when antiandrogen is discontinued. Although the androgen receptor (AR) is suggested to play an important role in prostate cancer progression even after the androgen ablation, limited tissue availability for molecular studies and small numbers of human prostate cancer cell lines have restricted prostate cancer research. Here, we describe KUCaP, a novel serially transplantable human prostate cancer xenograft model. We established KUCaP from liver metastatic tissue of a patient treated with antiandrogen bicalutamide. KUCaP expressed the AR with a point mutation at amino acid 741 (tryptophan to cysteine; W741C) in the ligand-binding domain. This mutation was also present in cancerous tissue used for generation of KUCaP. Although the growth of KUCaP in male mice was androgen dependent, bicalutamide aberrantly promoted the growth and prostate-specific antigen production of KUCaP. For the first time, we show the agonistic effect of bicalutamide to a xenograft with clinically induced AR mutation. This bicalutamide-responsive mutant AR will serve in the development of new therapies for androgen ablation-resistant prostate cancers.
Collapse
Affiliation(s)
- Toru Yoshida
- Department of Urology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Solakidi S, Psarra AMG, Nikolaropoulos S, Sekeris CE. Estrogen receptors alpha and beta (ERalpha and ERbeta) and androgen receptor (AR) in human sperm: localization of ERbeta and AR in mitochondria of the midpiece. Hum Reprod 2005; 20:3481-7. [PMID: 16123086 DOI: 10.1093/humrep/dei267] [Citation(s) in RCA: 150] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The central role of estrogens and androgens in the male reproductive system has focused attention on the presence and distribution of their cognate receptors [estrogen receptor (ER) alpha, ERbeta and androgen receptor (AR)] in male reproductive tissues and cells. Since the presence of steroid hormone receptors in mitochondria of mammalian cells has been well documented, we investigated the possibility of mitochondrial localization of sex steroid hormone receptors in sperm. METHODS AND RESULTS Applying immunofluorescence labelling and confocal laser scanning microscopy we show that the estrogen receptor beta and the AR of human sperm are specifically enriched in the midpiece, at the site of the mitochondria, which were visualized by labelling with the vital dye CMX. Nuclear and mitochondrial localization of AR was also detected in LnCap human prostate cancer cells. Differentially, most of the ERalpha immunostaining is in the form of a compact zone at a region corresponding to the equatorial segment of the upper post-acrosomal region of the sperm head. Immunoblotting experiments using sperm extracts revealed the presence of a 66 and a 45 kDa protein reacting with the ERalpha antibody, one 64 kDa protein reacting with the ERbeta antibody and a 110 and a 90 kDa protein reacting with the antibody against AR. CONCLUSIONS Our findings suggest that the differential localization of AR and ER isoforms in human sperm reveals distinct roles of these receptors in the physiology of sperm cells and, perhaps, also in the process of fertilization.
Collapse
Affiliation(s)
- S Solakidi
- National Hellenic Research Foundation, Institute of Biological Research and Biotechnology, Laboratory of Molecular Endocrinology, 48 Vas Constantinou Ave, 11635 Athens, Greece
| | | | | | | |
Collapse
|
35
|
Geserick C, Meyer HA, Haendler B. The role of DNA response elements as allosteric modulators of steroid receptor function. Mol Cell Endocrinol 2005; 236:1-7. [PMID: 15876478 DOI: 10.1016/j.mce.2005.03.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2005] [Accepted: 03/23/2005] [Indexed: 11/25/2022]
Abstract
Steroid receptors are ligand-activated transcription factors which control the expression of their target genes by binding to specific DNA elements. Consensus response elements have been delineated for the glucocorticoid, androgen, progesterone and mineralocorticoid receptors on one hand (steroid response element, SRE) and for the estrogen receptor on the other hand (estrogen response element, ERE). Small variations in these sequences not only affect the binding but may also have a dramatic impact on the transcriptional activity of steroid receptors. It has now become obvious that DNA response elements do not merely tether regulatory proteins to control regions of target genes but may additionally impart conformational changes onto the DNA-binding domain as well as to neighbouring domains of steroid receptors. This in turn will create unique platforms for selective recruitment of cofactors and possibly for induction of modifications in local chromatin architecture. An additional level of complexity is added by the frequent presence of multiple response elements in gene promoter regions. The allosteric effects of DNA response elements on steroid receptors may be essential for differential gene expression and this offers interesting perspectives for the identification of selective modulators.
Collapse
|
36
|
Church DR, Lee E, Thompson TA, Basu HS, Ripple MO, Ariazi EA, Wilding G. Induction of AP-1 activity by androgen activation of the androgen receptor in LNCaP human prostate carcinoma cells. Prostate 2005; 63:155-68. [PMID: 15486991 DOI: 10.1002/pros.20172] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND The androgen receptor and activator protein-1 (AP-1) transcription factors affect growth regulation in normal and cancerous prostate cells. Effects of androgen-activated androgen receptor on AP-1 activity were determined in the LNCaP human prostate carcinoma cell model. METHODS Cells were exposed to 1 nM androgen +/- antiandrogen bicalutamide. Cellular growth and cell cycle effects were determined by DNA, viability, and bromodeoxyuridine (BrdU) fluorescence activated cell sorter (FACS) assays. AP-1 effects were determined by an AP-1-luciferase enzyme reporter vector for transcriptional activity, electrophoretic mobility shift assay (EMSA)/antibody supershift for DNA-binding, quantitative RT-PCR for mRNA, and immunoblot for protein. RESULTS Androgen induced G(1) growth arrest. This growth arrest was abrogated by treatment with bicalutamide, demonstrating that growth arrest by androgen was due to androgen receptor activation. Concurrently, AP-1 DNA-binding and transcriptional activity was induced over 96 hr androgen exposure, which was also inhibited by bicalutamide. Interestingly, although no change in AP-1 transcriptional activity was observed 24 hr after androgen exposure, there was an increase in Fra-2 expression and AP-1 DNA-binding. Paradoxically, while Fra-2 mRNA and protein levels continued to increase, binding of Fra-2 to the AP-1 site decreased over 96 hr, with a concomitant increase in JunD AP-1-binding and a marked increase in expression of the 35 kDa form of JunD. Enhanced expression of this short form of JunD is a novel effect of androgen exposure that occurred during the 24-96 hr time period, as growth effects emerged. CONCLUSION Activation of androgen receptor by androgen induces changes in AP-1 activity and AP-1 factor DNA-binding that may contribute significantly to androgen-induced changes in prostate cancer cell growth.
Collapse
Affiliation(s)
- Dawn R Church
- University of Wisconsin Comprehensive Cancer Center, University of Wisconsin, Madison, USA
| | | | | | | | | | | | | |
Collapse
|
37
|
Sarfaraz S, Afaq F, Adhami VM, Mukhtar H. Cannabinoid Receptor as a Novel Target for the Treatment of Prostate Cancer. Cancer Res 2005; 65:1635-41. [PMID: 15753356 DOI: 10.1158/0008-5472.can-04-3410] [Citation(s) in RCA: 163] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cannabinoids, the active components of Cannabis sativa Linnaeus (marijuana) and their derivatives have received renewed interest in recent years due to their diverse pharmacologic activities such as cell growth inhibition, anti-inflammatory effects and tumor regression. Here we show that expression levels of both cannabinoid receptors, CB1 and CB2, are significantly higher in CA-human papillomavirus-10 (virally transformed cells derived from adenocarcinoma of human prostate tissue), and other human prostate cells LNCaP, DUI45, PC3, and CWR22Rnu1 than in human prostate epithelial and PZ-HPV-7 (virally transformed cells derived from normal human prostate tissue) cells. WIN-55,212-2 (mixed CB1/CB2 agonist) treatment with androgen-responsive LNCaP cells resulted in a dose- (1-10 micromol/L) and time-dependent (24-48 hours) inhibition of cell growth, blocking of CB1 and CB2 receptors by their antagonists SR141716 (CB1) and SR144528 (CB2) significantly prevented this effect. Extending this observation, we found that WIN-55,212-2 treatment with LNCaP resulted in a dose- (1-10 micromol/L) and time-dependent (24-72 hours) induction of apoptosis (a), decrease in protein and mRNA expression of androgen receptor (b), decrease in intracellular protein and mRNA expression of prostate-specific antigen (c), decrease in secreted prostate-specific antigen levels (d), and decrease in protein expression of proliferation cell nuclear antigen and vascular endothelial growth factor (e). Our results suggest that WIN-55,212-2 or other non-habit-forming cannabinoid receptor agonists could be developed as novel therapeutic agents for the treatment of prostate cancer.
Collapse
MESH Headings
- Adenocarcinoma/drug therapy
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Apoptosis/drug effects
- Benzoxazines
- Calcium Channel Blockers/pharmacology
- Cannabinoids/agonists
- Dose-Response Relationship, Drug
- Humans
- Male
- Morpholines/pharmacology
- Naphthalenes/pharmacology
- Neoplasms, Hormone-Dependent/metabolism
- Neoplasms, Hormone-Dependent/pathology
- Piperidines/pharmacology
- Proliferating Cell Nuclear Antigen/metabolism
- Prostate-Specific Antigen/genetics
- Prostate-Specific Antigen/metabolism
- Prostatic Neoplasms/drug therapy
- Prostatic Neoplasms/metabolism
- Prostatic Neoplasms/pathology
- Pyrazoles/pharmacology
- RNA, Messenger/metabolism
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/metabolism
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Rimonabant
- Time Factors
- Tumor Cells, Cultured
- Vascular Endothelial Growth Factor A
Collapse
Affiliation(s)
- Sami Sarfaraz
- Department of Dermatology, University of Wisconsin, Madison, Wisconsin 53706, USA
| | | | | | | |
Collapse
|
38
|
Abstract
Proper functioning of the mammalian testis is dependent upon an array of hormonal messengers acting through endocrine, paracrine, and autocrine pathways. Within the testis, the primary messengers are the gonadotrophins, follicle stimulating hormone and luteinizing hormone, and the androgens. Abundant evidence indicates that the role of the gonadotrophins is to maintain proper functioning of testicular somatic cells. It is the androgens, primarily testosterone, which act through the somatic cells to regulate germ cell differentiation. Despite extensive research in this area, little is known about the cell-specific requirements for androgens and even less is understood about the downstream effectors of androgen signalling. However, recent work using cell-specific ablation of androgen receptor function has demonstrated a clear requirement for androgen signalling at multiple, discrete time points during spermatogenesis. These models also provide useful tools for identifying the targets of androgen receptor activity. The purpose of this review is to provide a brief overview of recent advances in our understanding of hormonal regulation of spermatogenesis, with an emphasis on the role of testosterone within the testis, and to pose important questions for future research in this field.
Collapse
Affiliation(s)
- Robert W Holdcraft
- University of Washington, School of Medicine, Department of Genome Sciences, 1959 NE Pacific Street, Seattle, WA 98195-7730, USA
| | | |
Collapse
|
39
|
Kizu R, Otsuki N, Kishida Y, Toriba A, Mizokami A, Burnstein KL, Klinge CM, Hayakawai K. A new luciferase reporter gene assay for the detection of androgenic and antiandrogenic effects based on a human prostate specific antigen promoter and PC3/AR human prostate cancer cells. ANAL SCI 2004; 20:55-9. [PMID: 14753257 DOI: 10.2116/analsci.20.55] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
We developed a new mammalian cell-based luciferase reporter gene assay for androgenic and antiandrogenic activities of chemicals and environmental samples. Environmental samples usually have a complex matrix that may contain the constituents acting as androgen receptor (AR) agonists, AR antagonists or aryl hydrocarbon receptor (AhR) agonists. AhR agonists are known to elicit the antiandrogenic effect through cross-talk between AR and AhR signal transduction pathways. In this study, PC3/AR human prostate carcinoma cells were transiently transfected with a prostate-specific antigen (PSA) promoter-driven luciferase expression plasmid. The cells were treated with a test compound or an environmental sample for 24 h at 37 degrees C and then measured for luciferase activity. The luciferase activity was induced by dihydrotestosterone (DHT) in a concentration-dependent manner in a concentration range from 10 fM to 1 nM. R1881, a synthetic androgen receptor agonist, induced luciferase activity and its inductive effects was additive to that of DHT. The luciferase activity was not induced by cortisol, a glucocorticoid, progesterone, a progestin, and 17beta-estradiol, an estrogen in a concentration range of up to 1 microM. DHT-induced luciferase activity was reduced by bicalutamide and cyproterone acetate, AR antagonists, and also by benzo[a]pyrene, an aryl hydrocarbon receptor agonist, through AhR-mediated pathways. All of these findings indicate that the present assay system correctly responds to AR agonists, AR antagonists and AhR agonist and, therefore, it is a powerful tool for the sensitive and selective screening of chemicals and environmental samples for their androgenic and antiandrogenic activities. We developed the first assay system, in which the expression of luciferase was driven by the promoter of a prostate-specific antigen gene, a typical human androgen-regulated gene.
Collapse
Affiliation(s)
- Ryoichi Kizu
- Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa 920-0934, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Holdcraft RW, Braun RE. Androgen receptor function is required in Sertoli cells for the terminal differentiation of haploid spermatids. Development 2004; 131:459-67. [PMID: 14701682 DOI: 10.1242/dev.00957] [Citation(s) in RCA: 302] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Androgen receptor function is required for male embryonic sexual differentiation, pubertal development and the regulation of spermatogenesis in mammals. During spermatogenesis, this requirement is thought to be mediated by Sertoli cells and its genetic and pharmacological disruption is manifested in spermatocytes as meiotic arrest. Through studies of a hypomorphic and conditional allele of the androgen receptor (Ar) gene, we have uncovered a dual post-meiotic requirement for androgen receptor activity during male germ cell differentiation. Observations in Ar hypomorphic animals demonstrate that terminal differentiation of spermatids and their release from the seminiferous epithelium is AR dependent and maximally sensitive to AR depletion within the testis. Cell-specific disruption of Ar in Sertoli cells of hypomorphic animals further shows that progression of late-round spermatids to elongating steps is sensitive to loss of Sertoli cell AR function, but that progression through meiosis and early-round spermatid differentiation are surprisingly unaffected.
Collapse
Affiliation(s)
- Robert W Holdcraft
- University of Washington School of Medicine, Department of Genome Sciences, Seattle, WA 98195, USA
| | | |
Collapse
|
41
|
Cifuentes E, Mataraza JM, Yoshida BA, Menon M, Sacks DB, Barrack ER, Reddy GPV. Physical and functional interaction of androgen receptor with calmodulin in prostate cancer cells. Proc Natl Acad Sci U S A 2003; 101:464-9. [PMID: 14695896 PMCID: PMC327170 DOI: 10.1073/pnas.0307161101] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ca(2+) and calmodulin (CaM) play a critical role in proliferation and viability of a wide variety of cells, including prostate cancer cells. We examined two prostate cancer cell lines, androgen-sensitive LNCaP and androgen-independent PC-3. Proliferation of LNCaP cells was six to eight times more sensitive to the inhibitory effect of the CaM antagonist N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride (W-7) than were PC-3 cells. Because LNCaP cell proliferation is sensitive to stimulation by androgen, we assessed the physical and functional interaction between androgen receptor (AR) and CaM. We observed tight binding of AR to CaM when LNCaP cell extracts were subjected to CaM-affinity column chromatography. AR binding to CaM was Ca(2+)-dependent and was inhibited by pretreatment of the cell extracts with W-7. Using immunofluorescence staining and confocal microscopy, we demonstrated colocalization of AR and CaM in the nucleus of LNCaP cells. Furthermore, the functional relevance of AR-CaM interactions in intact cells was revealed by the observation that W-7 was as effective as Casodex, an antiandrogen, in blocking AR-regulated expression of prostate-specific antigen in LNCaP cells. AR seems to interact with CaM directly because purified human AR could bind to CaM-agarose, and CaM could be detected in AR-immunoprecipitate prepared from purified soluble proteins. These studies provide direct evidence for physical and functional interaction between AR and CaM and suggest the potential usefulness of CaM antagonists in blocking AR activity in prostate cancer.
Collapse
Affiliation(s)
- Eugenia Cifuentes
- Vattikuti Urology Institute, Henry Ford Health Sciences Center, Detroit, MI 48202, USA
| | | | | | | | | | | | | |
Collapse
|
42
|
Lee WJ, Thompson RW, McClung JM, Carson JA. Regulation of androgen receptor expression at the onset of functional overload in rat plantaris muscle. Am J Physiol Regul Integr Comp Physiol 2003; 285:R1076-85. [PMID: 14557238 DOI: 10.1152/ajpregu.00202.2003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Skeletal muscle androgen receptor (AR) expression at the onset of functional overload (OV) has not been well described. It is also not known if overload and/or anabolic steroid differentially regulate AR expression. The purpose of this study was to examine AR gene expression at the onset of functional OV in rat plantaris muscle with and without nandrolone decanoate (ND) administration. The functional significance of AR protein induction was examined using skeletal α-actin promoter activity in transiently transfected CV-1 fibroblast cells. Male Sprague-Dawley rats (∼125 g) were functionally overloaded for 1, 3, 7, or 21 days. A subset of animals was given an ND (6 mg/kg) injection at day 0 and then overloaded for 3 days. Control animals underwent sham surgeries. AR protein concentration increased 106 and 279% after 7 and 21 days of OV, respectively. AR mRNA increased 430% after 7 days of OV. AR protein expression in C2C12 murine myotubes subjected to 1% chronic radial stretch for 18 h was elevated 101% compared with control. ND treatment increased AR protein concentration 1,300% compared with controls, and there was no additional effect when ND and OV were combined. ND with 3 days of OV treatment increased AR mRNA expression 50% compared with control. AR overexpression in transiently transfected CV-1 fibroblast cells increased -424 bp skeletal α-actin promoter activity 80 to 1,800% in a dose-dependent fashion. Co-overexpression of either serum response factor (SRF) or active RhoA with AR overexpression induced a synergistic 36- and 28-fold induction of skeletal α-actin promoter. Cotransfection of AR, SRF, and active RhoA induced 180-fold increase in skeletal α-actin promoter activity. In conclusion, AR protein expression is increased after 7 days of functional OV, and this induction is regulated pretranslationally. AR induction in conjunction with SRF and RhoA signaling may be an important regulator of gene expression during overload-induced muscle growth.
Collapse
Affiliation(s)
- Won Jun Lee
- Univ. of South Carolina, Dept. of Exercise Science, 1300 Wheat St., Columbia SC 29208, USA
| | | | | | | |
Collapse
|
43
|
Le HT, Schaldach CM, Firestone GL, Bjeldanes LF. Plant-derived 3,3'-Diindolylmethane is a strong androgen antagonist in human prostate cancer cells. J Biol Chem 2003; 278:21136-45. [PMID: 12665522 DOI: 10.1074/jbc.m300588200] [Citation(s) in RCA: 135] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
3,3'-Diindolylmethane (DIM) is a major digestive product of indole-3-carbinol, a potential anticancer component of cruciferous vegetables. Our results indicate that DIM exhibits potent antiproliferative and antiandrogenic properties in androgen-dependent human prostate cancer cells. DIM suppresses cell proliferation of LNCaP cells and inhibits dihydrotestosterone (DHT) stimulation of DNA synthesis. These activities were not produced in androgen-independent PC-3 cells. Moreover, DIM inhibited endogenous PSA transcription and reduced intracellular and secreted PSA protein levels induced by DHT in LNCaP cells. Also, DIM inhibited, in a concentration-dependent manner, the DHT-induced expression of a prostate-specific antigen promoter-regulated reporter gene construct in transiently transfected LNCaP cells. Similar effects of DIM were observed in PC-3 cells only when these cells were co-transfected with a wild-type androgen receptor expression plasmid. Using fluorescence imaging with green fluorescent protein androgen receptor and Western blot analysis, we demonstrated that DIM inhibited androgen-induced androgen receptor (AR) translocation into the nucleus. Results of receptor binding assays indicated further that DIM is a strong competitive inhibitor of DHT binding to the AR. Results of structural modeling studies showed that DIM is remarkably similar in conformational geometry and surface charge distribution to an established synthetic AR antagonist, although the atomic compositions of the two substances are quite different. Taken together with our published reports of the estrogen agonist activities of DIM, the present results establish DIM as a unique bifunctional hormone disrupter. To our knowledge, DIM is the first example of a pure androgen receptor antagonist from plants.
Collapse
Affiliation(s)
- Hien T Le
- Department of Nutritional Sciences and Toxicology, The University of California, Berkeley, California 94720-3104, USA.
| | | | | | | |
Collapse
|
44
|
Kizu R, Okamura K, Toriba A, Kakishima H, Mizokami A, Burnstein KL, Hayakawa K. A role of aryl hydrocarbon receptor in the antiandrogenic effects of polycyclic aromatic hydrocarbons in LNCaP human prostate carcinoma cells. Arch Toxicol 2003; 77:335-43. [PMID: 12799773 DOI: 10.1007/s00204-003-0454-y] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2002] [Accepted: 01/30/2003] [Indexed: 10/20/2022]
Abstract
The role of aryl hydrocarbon receptor (AhR) on the antiandrogenic effects of polycyclic aromatic hydrocarbons (PAHs) was studied in LNCaP cells. The PAHs used in this study were chrysene (Chr), benzo[ k]fluoranthene (BkF), benzo[ a]pyrene (BaP), anthracene (Ant) and pyrene (Pyr). Chr, BkF and BaP acted as AhR agonists in LNCaP cells, while Ant and Pyr did not. The antiandrogenic effects of the PAHs were evaluated on the basis of regulation of prostate-specific antigen (PSA) mRNA and protein levels by 5alpha-dihydrotestosterone (DHT). Chr, BkF and BaP exhibited an antiandrogenic effect, but Ant and Pyr did not. alpha-Naphthoflavone (alpha-NF), an AhR antagonist, reversed the antiandrogen action of Chr, BkF and BaP, suggesting a requirement for activated AhR. The antiandrogenic PAHs did not significantly decrease androgen receptor (AR) levels or cellular DHT concentrations. Gel mobility shift assays revealed that Chr, BkF and BaP inhibited the binding of AR in nuclear extracts to oligonucleotide probes containing the AR-responsive element (ARE), whereas Ant and Pyr had no effect. The antiandrogenic PAHs elevated mRNA levels of c-fos and c-jun. Since activator protein-1 (AP-1), a heterodimer of c-jun and c-fos proteins, is known to inhibit binding of AR to ARE by protein-protein interaction with AR, the findings in the present study suggest a possible involvement of AP-1 in the antiandrogenic effects of PAHs acting as AhR agonists. These results suggest that AhR can stimulate AP-1 expression resulting in inhibition of the binding of AR to ARE in the transcription regulatory region of target genes such as PSA.
Collapse
Affiliation(s)
- Ryoichi Kizu
- Graduate School of Natural Science and Technology, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan.
| | | | | | | | | | | | | |
Collapse
|
45
|
Abstract
The androgen-androgen receptor (AR) signaling pathway plays a key role in proper development and function of male reproductive organs. Like other transcriptional regulators, AR may communicate with the general transcription machinery on the core promoter to exert its function as a transcriptional modulator. The molecular communication between AR and the general transcription machinery may be achieved either by the direct protein-protein interaction between AR and the general transcription machinery or by the indirect interaction mediated by coregulators. Analyses of AR-mediated transcription suggest that the orchestrated interaction of AR with the transcription factors IIF (TFIIF) and IIH (TFIIH), and positive transcription elongation factor b (P-TEFb), may increase efficiency of transcriptional elongation from the androgen target genes, such as prostate specific antigen (PSA). Based on studies so far, AR may regulate transcription not by enhanced assembly of preinitiation transcription complex but by regulating promoter clearance and elongation stage of transcription.
Collapse
Affiliation(s)
- Dong Kun Lee
- George Whipple Laboratory for Cancer Research, Department of Pathology, and the Cancer Center, 601 Elmwood Avenue, P.O. Box 626, Rochester 14642, NY, USA
| | | |
Collapse
|
46
|
Abstract
Prostate cancer (PCa) is the leading diagnosed malignancy in men in western countries. The relationship between androgens and the androgen receptor (AR) has been studied extensively in PCa. Plasma levels of androgens show variations between different populations, and in many cases this correlates with PCa susceptibility. Indeed, exposure of the fetus to higher androgen concentrations appears to be a risk factor for PCa. The AR is present in the majority of PCa, and its activation by androgens leads to different proliferative, apoptotic and angiogenic events. These events are in turn mediated by dysregulation of cyclin-dependent kinases, apoptotic factors and even mutations in the AR. Although androgen ablation has been the mainstay non-surgical treatment for this disease, most tumors will eventually become refractory to treatment. Different cellular mechanisms appear to be involved in the androgen-independent progression of PCa, including cytokine and growth factor-mediated activation of the AR as well as neuroendocrine differentiation. Thus, an understanding of the cellular mechanisms involved in androgen action may lead to better therapeutic targets for PCa.
Collapse
|
47
|
Lukyanenko Y, Chen JJ, Hutson JC. Testosterone regulates 25-hydroxycholesterol production in testicular macrophages. Biol Reprod 2002; 67:1435-8. [PMID: 12390873 DOI: 10.1095/biolreprod.102.007575] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Recently, we found that testicular macrophages produce 25-hydroxycholesterol (25-HC) and express 25-hydroxylase, the enzyme that converts cholesterol to 25-HC. In addition, 25-HC may be an important paracrine factor mediating the known interactions between macrophages and neighboring Leydig cells, because it is efficiently converted to testosterone by Leydig cells. The purpose of the present study was to determine if testosterone can regulate the production of 25-HC in rat testicular macrophages, representing a potential negative-feedback loop from Leydig cells. We found that expression of 25-hydroxylase mRNA and production of 25-HC by cultured testicular macrophages were significantly inhibited by testosterone at 10 micro g/ml. This dose of testosterone did not have an effect on cell viability and did not change the rate of mRNA degradation in the presence of actinomycin D. These studies indicate that production of 25-HC is negatively regulated by testosterone, which may be representative of a paracrine negative-feedback loop.
Collapse
Affiliation(s)
- Yevgeniya Lukyanenko
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, Lubbock, Texas 79430, USA
| | | | | |
Collapse
|
48
|
Abstract
Androgen receptor (AR) is a member of the steroid hormone receptor family of molecules. AR primarily is responsible for mediating the physiologic effects of androgens by binding to specific DNA sequences that influence transcription of androgen-responsive genes. The three-dimensional structure of the AR ligand-binding domain has shown it is similar to other steroid hormone receptors and that ligand binding alters the protein conformation to allow binding of coactivator molecules that amplify the hormone signal and mediate transcriptional initiation. However, AR also undergoes intramolecular interactions that regulate its interactions with coactivators and influence its activity. A large number of naturally occurring mutations of the human AR gene have provided important information about AR molecular structure and intermolecular interactions. AR is also a critical mediator of prostate cancer promotion, conferring growth signals to prostate cancer cells throughout the natural history of the disease. Late-stage prostate cancer, unresponsive to hormonal deprivation, sustains AR signaling through a diverse array of molecular strategies. Variations in the AR gene may also confer genetic predisposition to prostate cancer development and severity. Further understanding of AR action and new strategies to interfere with AR signaling hold promise for improving prostate cancer therapy.
Collapse
Affiliation(s)
- Edward P Gelmann
- Department of Oncology, Lombardi Cancer Center, Georgetown University School of Medicine, 3800 Reservoir Rd NW, Washington, DC 20007-2197, USA.
| |
Collapse
|
49
|
Pero R, Lembo F, Palmieri EA, Vitiello C, Fedele M, Fusco A, Bruni CB, Chiariotti L. PATZ attenuates the RNF4-mediated enhancement of androgen receptor-dependent transcription. J Biol Chem 2002; 277:3280-5. [PMID: 11719514 DOI: 10.1074/jbc.m109491200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PATZ is a transcriptional repressor affecting the basal activity of different promoters, whereas RNF4 is a transcriptional activator. The association of PATZ with RNF4 switches the activation to repression of selected basal promoters. Because RNF4 interacts also with the androgen receptor (AR) functioning as a coactivator and, in turn, RNF4 associates with PATZ, we investigated whether PATZ functions as an AR coregulator. We demonstrate that PATZ does not influence directly the AR response but acts as an AR corepressor in the presence of RNF4. Such repression is not dependent on histone deacetylases. A mutant RNF4 that does not bind PATZ but enhances AR-dependent transcription is not influenced by PATZ, demonstrating that the repression by PATZ occurs only upon binding to RNF4. We also demonstrate that RNF4, AR, and PATZ belong to the same complex in vivo also in the presence of androgen, suggesting that repression is not mediated by the displacement of RNF4 from AR. Finally, we show that the repression of endogenous PATZ expression by antisense expression plasmids in LNCaP cells results in a stronger androgen response. Our findings demonstrate that PATZ is a novel AR coregulator that acts by modulating the effect of a coactivator. This could represent a novel and more general mechanism to finely tune the androgen response.
Collapse
Affiliation(s)
- Raffaela Pero
- Centro di Endocrinologia ed Oncologia Sperimentale del CNR "G. Salvatore," Dipartimento di Biologia e Patologia Cellulare e Molecolare, "L. Califano" Università degli Studi di Napoli "Federico II," via S. Pansini, 5, 80131 Napoli, Italy
| | | | | | | | | | | | | | | |
Collapse
|
50
|
Rosen G, O'Bryant E, Matthews J, Zacharewski T, Wade J. Distribution of androgen receptor mRNA expression and immunoreactivity in the brain of the green anole lizard. J Neuroendocrinol 2002; 14:19-28. [PMID: 11903809 DOI: 10.1046/j.0007-1331.2001.00735.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Male courtship and copulation are androgen dependent in the green anole lizard, and female receptivity can be facilitated by testosterone. However, only a few, and relatively large, regions in the brain have been implicated in the control of these behaviours. In situ hybridization and immunohistochemistry were therefore used to determine in detail where androgens are likely to act in the brains of breeding males and females. A 697-bp fragment of the anole androgen receptor (AR) was cloned from total RNA isolated from the kidney, which contains the highly androgen-sensitive renal sex segment. The cloned fragment spanned part of the C, the entire D, and part of the E domains, and shared a high degree of similarity with the AR of various species. 35S-labelled antisense and sense probes were generated from the 697-bp fragment for use in in situ hybridization, and the AR antibody PG-21 was used for immunohistochemistry. Both sexes consistently had AR mRNA expression and immunoreactivity in areas associated with vertebrate reproductive behaviours and in motor areas of the brainstem. Interestingly, the PG-21 antibody produced labelling in both the nucleus and cytoplasm, including neuronal processes. The distribution of mRNA and immunoreactivity were comparable in males and females, and the amount of labelling was generally similar, although slightly greater in females. The expression pattern of AR in this species supports the idea that distribution is highly conserved among vertebrates, but that it probably does not dictate behavioural differences between the sexes in anoles.
Collapse
Affiliation(s)
- G Rosen
- Department of Psychology, Michigan State University, East Lansing, MI 48824, USA
| | | | | | | | | |
Collapse
|