Aberrant androgen receptor (AR) activity plays a critical role in the development and progression of both early-staged organ-confined and late-staged metastatic human prostate cancer. Recent large-scale genomic sequencing studies showed that ~50% of organ-confined prostate cancer patients have genetic rearrangements that placed the ETS transcription factors (e.g. ERG, ETV1) under the control of androgen-regulated gene promoters such as TMPRSS2. This results in the upregulation of the ETS transcription factors’ expressions in the presence of androgens. The aberrant overexpression of the ETS transcription factors are shown to induce the expression of genes that promote the cellular motility and invasive potential of prostate-tumor cells. Moreover, the improved therapeutic outcome of the second-generation anti-androgen therapies (e.g. abiraterone and enzalutamide) are encouraging, and prove that aberrant AR activity still drives the progression of metastatic prostate cancer. Although these treatments are initially effective, these cancer cells eventually develop resistance to these AR-targeted therapies termed castration-resistant prostate cancer (CRPC). Since the molecular steps involved in AR activation is still not clearly defined, it is critical to define the interactions required for AR activation prostate cancer cells, which will provide a framework for establishing more effective treatments to inhibit aberrant AR activity in human prostate cancer cells. Here, I developed a cellular system to isolate ligand-dependent interactions of AR in prostate-tumor cells. A siRNA luciferase screen was also developed and identified novel modulators of AR-mediated transcription selected from the proteomic dataset. Further biochemical studies showed that AR is associated with the Golgi membrane in a ligand-sensitive manner. And that the nuclear localization of ARA160, an AR coactivator, is regulated by the COPI retrograde trafficking machinery. Collectively, these results support the use of this cellular system to decipher the known AR-interacting proteins and novel components involved in AR signaling in prostate-tumor cells. I next investigated the androgen-sensitive AR transcriptional complexes and androgen-sensitive microsomes isolated from LNCaP prostate-tumor cells. Both studies yielded results that would further strengthen the diverse AR actions mediated within the cell. These results further support the notion that there is significant crosstalk amongst different cell surface receptor signaling pathways with AR. An extension of the androgen-sensitive microsome findings also led us to study the androgen-sensitive G-protein coupled receptor, CXCR7. I showed that androgens regulate the expressions of CXCR7 and CXCR4 and in turn modulated CXCL12-mediated motility in prostate tumor cells. Lastly, biochemical strategies were developed to detect differences in glycoprotein expression of frozen prostate cancer tissues isolated from human patients. I showed that the workflow successfully solubilized and isolated N- and O-linked glycoproteins from the frozen tissue samples and can be analyzed by quantitative mass spectrometry. This workflow would thus facilitate future biomarker studies. In summary, these data demonstrate the utility of developing methods for the comprehensive mapping of AR-mediated signaling in prostate cancer cells, and thus provide novel target candidates for the therapeutic treatment of metastatic or CRPC.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21995号 / 医博第4509号 / 新制||医||1037(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 戸井 雅和, 教授 万代 昌紀, 教授 武藤 学 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

We report a de novo dup(X)(q23→q26) in a 3-year-old girl with growth retardation, developmental delay, and minor anomalies. X-inactivation in lymphocytes by BRDU labeling showed the abnormal X was late replicating. The androgen receptor assay (HAR) demonstrated a skewed methylation (88.8%) of the paternal allele and a 11.2% methylation of the maternal allele. These data, which suggest the duplication was paternally inherited, are the first parental-origin identification of a duplication Xq. The mild phenotype of the patient may be related to the size and region of the duplication, the low percentage of a dup(X) active detected by the HAR assay, or a combination of these mechanisms. .

Androgen receptor (AR) gene CAG polymorphisms may be associated with body shape, and are associated with certain breast and prostate cancers. In addition, body shape is associated with risk for a variety of diseases, including heart disease, diabetes, and certain forms of cancer. The CAG repeat in exon l of the AR gene was quantified using Perkin Elmer Applied Biosystems GeneScan analysis software in 96 and 59 healthy Caucasian men and women, respectively, who were over the age of 50 years. All participants had body measurements taken and donated a blood sample. Waist measurements included circumferences at the 1) umbilicus (wstumb), 2) top of the iliac crest (wstili), and 3) midpoint between the lowest rib and the iliac crest (wstwst). Waist-hip ratio (Wl-IR) was calculated using each corresponding waist measurement, respectively (WHRUMB, WHRILI, WHRWST). Mean repeat length was significantly different (p < 0.01) between men (22 ± 0.3 repeats) and women (23 ± 0.3 repeats). There was a significant relationship (p < 0.05) between mean individual CAG repeat number and tertile of WHRUMB in women based on the mean number of CAG repeats for each woman. Waist measurements in women were significantly different for all pairwise comparisons (p < 0.05). In addition, the three measurements of WHR in women, WHRUMB, WHRILI, and WHRWST, were significantly different from each other (p < 0.05). Thus, lesser numbers of CAG repeats may indicate a more androgenic phenotype in women.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19545号 / 理博第4205号 / 新制||理||1603(附属図書館) / 32581 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 村山 美穂, 教授 幸島 司郎, 教授 伊谷 原一 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

No description available.

We describe an 11 year old girl with a de novo unbalanced t(X;10) that resulted in a deletion of Xq26→Xqter and a trisomy of 10q21→10qter. Her clinical features were of distal trisomy 10q, but she lacked the cardiovascular and renal malformations observed in duplications of 10q24→10qter and had only moderate mental retardation. X inactivation was assessed on peripheral blood lymphocytes by late replication with BrdU (LR) and the human androgen receptor assay (HAR). By LR the der(X) was inactive without spreading to 10q21→10qter in all cells. The HAR assay showed skewed methylation of the paternal allele (90%). The correlation of HAR and LR suggests that the der(X) was paternally inherited and is consistent with data from other de novo balanced and unbalanced X;autosome translocations detected in females. This is the first report of parental origin of a de novo trisomy 10q.

No description available.

Prostate cancer is the most commonly diagnosed non-skin cancer in men and the second leading cause of cancer death in the United States. Prostate cancer, like many cancers, is a disease that generally requires a long period of time to develop and grow before it becomes detectable. This long period of latency makes prostate cancer a candidate for dietary chemoprevention. Soy and selenium (Se), are associated with a decreased risk of prostate cancer. We previously showed that high dietary intake of selenium (Se) and soy isoflavones decreased the expression of the androgen receptor (AR) and AR-regulated genes in the prostates of healthy rats. In this study we hypothesized that the downregulation of AR and AR-regulated genes would inhibit tumorigenesis in the transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse. Mice were fed one of two stock diets with or without a supplement of Se in a 2 X 2 factorial design. The stock diets provided high or low dietary isoflavones. Mice were exposed to the diets from conception and sacrificed at 18 or 24 weeks of age. Prostate histopathology, urogenital tract (UGT) weight, serum IGF-1 levels, and the expression of AR and AR-regulated genes in the dorsolateral prostate was examined using quantitative PCR and Western blotting. Urogenital tract (UGT) weight was reduced compared to control in all dietary groups containing high Se, isoflavones, or both at 24 weeks (p<0.005). Dietary isoflavones delayed tumor progression and downregulated protein levels of AR, AR-regulated genes, and upregulated the protective FOXO1 and FOXO3a transcription factors. High dietary isoflavones also decreased the phosphorylation of the IGF-1R. The only main effect of Se was the upregulation of AKR1C14 the enzyme that deactivates 5&aplha;-DHT.This study identifies a previously unknown effect of isoflavones in the upregulation of FOXO expression and confirms previous studies of isoflavones' anticancer effects. Further research is needed to find a protective dose or form of Se and to elucidate the mechanism of isoflavones.

Prostate cancer is the second most commonly occurring cancer in men in the United States. Generally, an extended period of time is needed for a mutation to develop into a full scale tumor. Because of this long latency period, lifestyle and environmental factors, such as diet, may play an important role in the development and progression of the disease. Diet is one factor that has been implicated in the risk for developing prostate cancer. We previously showed that diets high in soy isoflavones and selenium (Se) decreased androgen receptor expression and expression of androgen regulated genes in healthy rat prostates. The purpose of this study was to determine whether treatment of soy isoflavones and/or supplemental Se provide chemopreventive effects in the Transgenic Adenocarcinoma of Mouse Prostate (TRAMP) model of prostate cancer, and whether the timing of the introduction of these nutrients determines protective effects. Male hemizygous C57/BL6 x FVB TRAMP mice were exposed to a diet high in isoflavones, a 4 mg/kg daily bolus of supplemental Se as methylselenocysteine (MSC), or the combination of high isoflavones and MSC starting at one of two time points: conception or 6 weeks of age, and were killed and dissected for prostate tissue, liver, and serum at either 4 weeks or 12 weeks of age (n per dietary treatment = 20: total mice = 240). Treatment with MSC resulted in decreased urogenital tract weight at 4 and 12 weeks. Treatment with MSC and isoflavones, both individually and as a combination, resulted in decreased androgen receptor expression, 5 alpha-reductase levels, and aromatase levels. The combination of MSC and a basal diet high in isoflavones resulted in decreased serum IGF-1 levels in 12 week TRAMP mice. Treatment from conception resulted in greater decreases in urogenital tract weight, 5 alpha-reductase expression, and aromatase expression than treatment from 6 weeks. This study demonstrated that in 12 week TRAMP mice, reductions in risk factors for prostate cancer by treatments of high isoflavones and supplemental Se are maximized by introduction to treatments at conception.