Social interactions can have profound effects on the behavior, physiology, and overall fitness of an individual. An example of this in Lythrypnus dalli is the removal of a male from a social group resulting in a dominant female fish changing sex. The dominant female's transformation involves a suite of changes including brain, behavior, morphology, and physiology. Following the social trigger (male removal), sex-changing individuals' morphology, steroid levels, and changes in the behavior were quantified in the field and compared to results found previously in the laboratory. There were lower rates of aggressive and courtship behavior in the field, but the change in behavior over time had a similar pattern and there were parallels in morphology and steroid levels between lab and field sex changers. The brains of dominant females also responded to social change. Aromatase, an enzyme that converts testosterone into estrogen, and oxytocin, a neuropeptide found in mammals, have been associated with vertebrate social and reproductive behavior. The fish homologue of oxytocin, isotocin, and aromatase are both found in L. dalli. Upon removal of a male from the social group, L. dalli dominant females experienced a decrease in the number of preoptic area isotocin-immunoreactive cells over the course of sex change (7-10 days) and a decrease in brain aromatase activity (bAA) levels within hours, but not minutes, of male removal, while gonadal aromatase activity (gAA) decreased at a much slower time scale (beyond a week). Hours, but not minutes, after male removal, the sex-changing individual's bAA correlated with aggressive behavior increases and not the amount of time following male removal. Males that had just changed from female had different gonadal allocation and higher bAA levels than established males. Subordinate females had high gAA, but their bAA was between that of males and sex changers. In conclusion, dramatic changes in anatomy and neuroendocrine function can occur in response to social cues, individuals with similar reproductive behavior and external morphology can have large neuroendocrine and internal morphologic variation, and social interactions can affect steroid metabolism locally on a short time scale independent of gonadal modulation of steroids.

Introduction: Sexual hormone-binding globulin (SHBG) is a protein that binds to androgens and oestrogens, especially testosterone. The fraction of testosterone that is not bound to SHBG is the biologically active fraction which makes its determination more relevant than determining the total amount of circulating testosterone. It is difficult to measure the plasma concentration of free testosterone; therefore calculations using the concentrations of testosterone and SHBG are used to estimate the amount of free testosterone. A few calculations include the concentration of albumin because testosterone also binds to albumin. The main aims of this study were to verify a method for the determination of SHBG and to calculate a reference interval for free androgen index (FAI, testosterone/SHBG) in women. Other calculations for determination of the free testosterone fraction were compared. Methods: Testosterone, SHBG and albumin were measured in serum from 20 men and 100 women. Testosterone and SHBG was measured using immunoassays on a Roche Modular E instrument (ECLIA). Albumin was measured with a c8000 Architect instrument. Four calculations, two with only testosterone and SHBG and two with testosterone, SHBG and albumin were compared.  Results/Conclusion: The verification of the SHBG method was successful which means that the method can be taken into routine use. A reference interval for FAI was constructed. It was difficult to show if other estimation of free testosterone would work better than FAI in clinical practice. This is discussed.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 24-28).

Androgens and the androgen receptor (AR) play important roles in virilization, spermatogenesis, and sexual behavior in vertebrates. An understanding of the distribution and levels of expression of the ARs on the cellular and tissue level demonstrates the pattern of responsiveness to the androgenic hormones in a given organism. In this study, a fragment of the AR gene was cloned and sequenced from the bonnethead shark, Sphyrna tiburo, an elasmobranch species with a well-defined annual reproductive cycle. Acquiring this gene sequence facilitated the construction of species-specific AR polymerase chain reaction (PCR) primers and species-specific AR mRNA probes that were used to screen reproductive tissues for evidence of AR gene expression using reverse transcription (RT)-PCR and in situ hybridization (ISH), respectively. The RT-PCR screens demonstrated AR gene expression in the testes, epididymides, seminal vesicles, and claspers of male sharks. The use of relative PCR revealed that these organs have variable levels of AR gene expression that significantly differ with the stage of the shark's seasonal reproductive cycle. ISH results localized the AR RNA in the interstitial cells, Sertoli cells, and developing sperm of the testes, and mature spermatozoa within the seminal vesicles and the epididymides. Immunocytochemical methods used to detect the AR protein using a rabbit polyclonal antibody, PG-21, produced comparable results in the shark testes but did not yield positive results in the seminal vesicles or the epididymides. However, the Leydig gland, whose secretions contribute to the seminal fluid, demonstrated consistent AR immunoreactivity. Results of ICC in male and female embryos of S. tiburo revealed AR protein in the developing kidney but not in the embryonic reproductive structures. By characterizing AR distribution in the reproductive tract of male S. tiburo, this study provides the basis for future research on the direct and indirect effects of androgenic hormones in this species.

Prostate cancer is frequently diagnosed in elderly men and, despite the largely unproven survival benefits of treatment, the majority receive treatment. Treatment options include surgery, radiation, and/or androgen deprivation therapy (ADT). Risks associated with treatment include hip fracture. Current understanding suggests that hip fracture is a frequent cause of morbidity and mortality in the elderly, and both radiation treatment and ADT can increase the risk of hip fracture. It is important to understand these risks so they can be minimized and the morbidity of treatment reduced. The objectives of this study were to estimate the risk of hip fracture as a major adverse outcome of treatment for prostate cancer among elderly men. The specific objectives include estimating: 1) the risk of hip fracture and the dose-risk relationship among patients receiving curative radiation treatment, and 2) the risk of hip fracture associated with palliative ADT and relapsed ADT compared to curative ADT. The cancer diagnosis and treatment records of 32,673 men were linked to their hospital discharge abstracts. The risk of hip fracture was estimated using Cox regression and the estimates were adjusted for age, comorbidity, income, and year of diagnosis. The risk of hip fracture was 59% higher among men who received curative radiation when compared to men who received curative surgery. The risk of hip fracture fell by 6% with each one Gy increase in radiation dose between 55 and 81 Gy Biological Equivalent Dose to the hip-bone. The risk of hip fracture for subjects in the palliative ADT and relapsed ADT categories was 5.98 and 5.77 times the risk in comparison to men who received curative ADT treatment. Curative radiation treatment is associated with an increased risk of hip fracture when compared to curative surgery. The risk of hip fracture is greater with ADT for palliation and relapsed cancer than with curative treatment. Current treatments for prostate cancer contain significant risk of hip fracture for elderly men and these risks should be considered as part of the treatment decision.

Advanced prostate cancer (PCa) patients are offered androgen deprivation therapy (ADT) to control their cancer’s growth. ADT impairs sexual function and the sleep patterns of ADT patients. Since ADT deprives patients of estrogen, and supplemental estrogen reduces such problems in menopausal women, I studied whether administering estrogen reduces these problems for castrated male rats as a model for PCa patients on ADT. First, I tested how early versus late estradiol treatment after castration influenced rats’ sexual behaviour. Estradiol increases mounting behaviour to comparable levels regardless of when the treatment was started after castration, suggesting that estrogen’s ability to restore male sexual interest is insensitive to a delay since castration. Secondly, to understand the biological basis of these behavioural effects, I examined brain and muscle tissues from the same animals. Specifically, I compared changes in 1) estrogen receptors (ERs) and c-Fos protein (a neuronal activation marker) levels in brain areas controlling sex behavior; 2) ERs levels in pelvic floor muscles, important for erection; and 3) ERs levels in the hippocampus and prefrontal cortex. Prolonged castration increases ER? levels in the preoptic area (POA), a key brain area that regulates mating behaviour, and estradiol treatment reduced these effects. In the POA, mating-induced c-Fos expression was not affected by estradiol regardless of when the treatment began post-castration. Estrogen may upregulate ERs in pelvic floor muscles, and downregulate ERs in the hippocampus and prefrontal cortex, depending on administration time after castration. These findings suggest that mating activates POA neurons, and this activation induces mounting only in the presence of estrogen. Additionally, the duration after castration influences ER autoregulation in the pelvic floor muscles, hippocampus, and prefrontal cortex in response to estradiol. Lastly, I studied how estrogen modulates the sleep-wake behaviour of orchiectomized rats. Estradiol promotes baseline wakefulness during the dark period and prevents castration-induced impairment in sleep recovery after sleep deprivation. These findings suggest that estradiol may positively influence the sleep-wake behaviour of castrated males. Collectively, I demonstrate that estrogen administered to castrated rats improves sexual and sleep functions. It may similarly improve the quality of life of PCa patients on ADT.

Cancer is the second leading cause of death in the United States (more than half a million people each year), and even with billions of dollars in medical effort patients are rarely cured. This dissertation research is devoted to meeting this medical need by providing new cancer therapeutics that are more potent and safer than current chemotherapies. This is achieved by using two state of the art anticancer “warheads”: 1) gold nanoparticle (AuNP) technology and 2) a new class of epigenetic anticancer small molecules, histone deacetylase inhibitors (HDACi). These warheads are then selectively delivered to cancer cells via “homing devices” targeted to receptors that are overexpressed in the cancers. This work primarily focuses on the androgen receptor (AR) to target prostate cancer. The 1st chapter sets the stage, providing scientific rationale and background for the central hypothesis: small molecules that engage the AR can, upon conjugation to a therapeutic agent, enable selective delivery of that agent to prostate cancer cells. Chapter 2 delves into the structural molecular biology of the androgen receptor. There is a survey of the crystallographic data for all nuclear receptors, providing structural information which is used to build AR homology models for antagonist and inverse agonist modes of ligand binding. These models are used to design AR targeting ligands (Chapters 3, 5, 6 and 7). The application of the targeting technology is illustrated by attaching them to AuNPs for selective delivery to prostate cancer cells (Chapter 3). Next, in order to appreciate the importance of using targeting agents in HDACi cancer therapeutics, we reviewed this recently emerged field in Chapter 4. In this chapter we argue that the failure of HDACi in solid tumors, despite more than 500 clinical trials in the last decade, is primarily due to an inability of these small molecules to accumulate at effective concentrations in the cancer. We provide an analysis of the paradigms being pursued to overcome this barrier, including HDAC isoform selectivity, localized administration, and targeting cap groups to achieve selective tissue and cell type distribution. In Chapter 5, this last approach (targeting cap groups, or a “homing device”) is illustrated with HDACi targeted to prostate cancer via antiandrogens that bind the AR. The second generation of improved “homing devices” is disclosed in Chapter 6 (for both AuNPs and HDACi), in addition to preliminary ADMET data and safety studies in mice. Excitingly, our three dimensional understanding of binding to the AR allowed design and structure-activity-relationship studies that lead to the first reported examples of AR inverse agonists (Chapter 7) Several points of significance: • AuNP targeted to AR ∙ have the strongest binding affinity ever reported (IC50 ~14 picomolar) ∙ are actively recruited to prostate cancer cells ∙ overcome treatment resistance in advanced prostate cancer cells ∙ exhibit nanomolar anticancer potency ∙ resolved the identity of the “membrane AR” as the GPRC6A • HDACi targeted to AR ∙ have HDACi activity and AR binding affinity superior to their clinical precursors ∙ exhibit potent AR antagonist activity ∙ induce AR translocation to the nucleus in a HDACi dependent fashion ∙ selectively and potently kill prostate cancer cells that express AR ∙ are safer than Tylenol®, as tested in small animals • Pure AR binding ligand studies ∙ resulted in the discovery of the first examples of AR inverse agonists, which are vastly more potent that clinically available antiandrogens for prostate cancer ∙ work via a never-before-seen mechanism of action, by localizing to the nucleus and recruiting corepressors to actively shut off AR genes

Prostate cancer is the most frequently diagnosed non-skin cancer and the third leading cause of cancer mortality among men in the US. Androgens are functionally required for the normal growth of the prostate gland and play a critical role in prostate tumor development and progression. Epithelial-mesenchymal-transition (EMT) is an important process during normal development, and cancer cell metastasis. This study examined the ability of androgens to influence EMT of prostate cancer epithelial cells and evaluate the effect of taxol chemotherapy on androgen signaling in prostate cancer cells in prostate cancer. The EMT pattern was evaluated on the basis of expression of the epithelial markers as well as cytoskeleton reorganization in respond to DHT (1nM) and/or TGFβ (5ng/ml). Overexpressing and silencing approaches to regulate androgen receptor (AR) expression were conducted to determine the involvement of AR in EMT in the presence or absence of an AR antagonist. The AR transcriptional activity was determined on the basis of prostate specific antigen (PSA) mRNA expression and the androgen-response element (ARE) luciferase reporter assay. The interaction of AR and tubulin was investigated using immunoprecipitation, immunofluorescence as well as introduction of a truncated AR in human prostate cancer cells. Our results demonstrate that androgens induce the EMT pattern in prostate tumor epithelial cell with Snail activation and led to significant changes in prostate cancer cell migration and invasion potential. Expression levels of AR inversely correlated with androgen-mediated EMT in prostate tumor epithelial cells, pointing to a low AR content required for the EMT phenotype. Our study also reveals that treatment of prostate cancer cells with Paclitaxel or Nocodaxol inhibits androgen-dependent, as well as androgen-independent AR nuclear translocation and activation potentially via targeting the interaction of AR and microtubule cytoskeletal structures. Our findings on multiple aspects of AR function in prostate cancer development and progression may enhance the understanding of AR targeting therapy being a double-sided sword in the context of tumor microenvironment. These studies provide new insights into the mechanism of action of chemotherapy agents and the development of therapeutic resistance within tubulin/microtubule repertoire in prostate cancer cells.

The purpose of this study was to determine whether androgen promotes AT1aR expression on smooth muscle to confer high prevalence of AngII-induced AAAs in hyperlipidemic mice. In addition, we also investigate the role of androgen in the progression of established AngII-induced AAAs. First, we sought to examine the role of endogenous androgen in the growth of established AngII-induced AAAs. By castrating male mice, we demonstrated that removal of endogenous androgen significantly decreased the progressive lumen dilation of established AngII-induced AAAs in male ApoE-/- mice, but had no effect on external AAA diameters. These results suggest that androgen contributes to the progression of established AAAs through distinct mechanisms that differentially influence aortic lumen and wall diameters. We also investigate whether androgen regulates aortic AT1aR expression to promote AngII-induced AAA formation. Our data demonstrated that in male and female mice, both endogenous and exogenous androgen stimulate AT1aR level particularly in abdominal aortas. This androgen-dependent enhanced expression of abdominal aortic AT1aR was correlated with increased AngIIinduced AAA formation in male and female mice. Smooth muscle AT1aR deficiency significantly reduced luminal and external diameters of abdominal aortas as well as the incidence of AngII-induced AAAs in adult female mice administered exogenous androgen. Collectively, these results indicate that in adult mice androgen stimulate smooth muscle AT1aR expression to promote AngII-induced AAA formation. To determine the role of androgen during development on AT1aR expression on SMC and AngII-induced vascular pathologies, we exposed neonatal female mice to one single dose of testosterone. Our data demonstrated that neonatal testosterone administration dramatically increased AngII-induced AAA, atherosclerosis and ascending aortic aneurysms in adult female mice. In addition, smooth muscle AT1aR deficiency reduced effects of neonatal testosterone to promote AAAs, but had no effect on the other two AngII-induced vascular pathologies. In summary, our findings demonstrated that androgen, both in adult life and during development, stimulate smooth muscle AT1aR expression and promote AngII-induced AAA in female hyperlipidemic mice.

Androgens are the main regulators of human hair growth stimulating larger, terminal hair development e.g. beard and causing scalp balding, androgenetic alopecia. Hair disorders cause psychological distress but are poorly controlled. Androgens probably act by altering regulatory paracrine factors produced by the mesenchyme-derived dermal papilla. This study aimed to investigate paracrine factors involved in androgen-regulated alopecia, particularly hepatocyte growth factor (HGF) family members, by investigating their in vivo status. Balding and non-balding scalp hair follicles and their component tissues were isolated and analysed by molecular biological methods (reverse transcriptase-polymerase chain reaction (RT-PCR), quantitative PCR and DNA microarray analysis), cell culture and immunohistochemistry. Scalp follicles expressed a range of paracrine messenger genes. The dermal papilla, cultured dermal papilla cells and dermal sheath expressed several HGF family genes, while matrix cells only produced the receptor RON suggesting autocrine roles for HGF and MSP, but a paracrine route only for MSP. Comparing balding and non-balding follicles from the same individuals revealed the expected reduction in several keratin and keratin-related protein genes supporting this approach's validity. There were also significant differences in paracrine factors previously implicated in androgen action by in vitro studies. Several factors believed to increase during androgen stimulation of larger, darker follicles, e.g. IGF-I and SCF, were lowered in balding follicles, while putative inhibitory factors, e.g. TGFß-1, were increased. HGF and MSP and their receptors, c-Met and RON, were significantly reduced. These results increase our understanding of androgen action in human hair follicles; this could lead to better treatments for hair disorders.