Androgen Receptor Protein Expression Research Articles

Adolescent exposure to bisphenol-a antagonizes androgen regulation of social behavior in male mice

Social behavior is sexually dimorphic, which is regulated by gonadal hormones in the brain. Our recent study found that exposure to low doses of bisphenol-A (BPA) during adolescence, permanently alters social behavior in adult male mice, but the underlying mechanisms remain unclear. Using adolescent gonadectomy (GDX) male mice with testosterone propionate (TP, 0.5 mg/kg) supplement (TP-GDX), this study showed that BPA antagonized promoting effects of TP on social interaction, sexual behavior, and aggression in GDX mice. BPA eliminated the reversal effects of TP on GDX-induced decrease in the number of immunoreactive to arginine vasopressin (AVP-ir) neurons in the medial amygdala (MeA) and the levels of AVP receptor 1a (V1aR) in the MeA and the nucleus accumbens (NAc). In addition, BPA removed down-regulation in the levels of dopamine (DA) transporter (DAT) and DA receptor 1 (DR1) in the NAc of TP-GDX mice. BPA exposure reduced testosterone (T) levels in the brain and serum and the expression of androgen receptor (AR) protein in the amygdala and striatum of sham-operated and TP-GDX males. These results suggest that adolescent exposure to BPA inhibits regulation of androgen in AVP and DA systems of the brain regions associated with social behavior, and thus alters social behaviors of adult male mice.

The influence of ghrelin agonist ipamorelin acetate on the hypothalamic-pituitary-testicular axis in a cichlid fish, Oreochromis mossambicus

Ghrelin, a peptide found in the brain and gut, is predicted to play a significant role in the control of various physiological systems in fish. The objective of this study was to examine the impact of ipamorelin acetate (IPA), a ghrelin agonist, on the reproductive axis of the tilapia Oreochromis mossambicus. The administration of either 5 or 30 µg of IPA for 21 days led to a significant and dose-dependent rise in food intake concomitant with a significant increase in the numbers of primary spermatocytes, secondary spermatocytes, and early spermatids compared to the control group. There was a significant rise in the number of late spermatids, as well as the areas of the lobule and lumen, in fish treated with 30 µg of IPA, compared to the control group. Moreover, there was no significant difference in the percentage of gonadotropin-releasing hormone (GnRH)-immunoreactive fibres in the hypothalamus and anterior pituitary gland across different groups. However, a significant elevation in the expression of androgen receptor protein was observed in fish treated with 30 µg of IPA. Furthermore, the concentrations of luteinizing hormone (LH) and 11-ketotestosterone (11-KT) in the serum of fish treated with either 5 or 30 µg of IPA were significantly elevated in comparison to the control group. Collectively, these findings suggest that the administration of ghrelin enhances the development of germ cells during the meiosis-I phase and that this effect might be mediated via the stimulation of 11-KT and androgen receptors at the testicular level and LH at the pituitary level in the tilapia.

Targeting androgen receptor signaling in glioblastoma: A novel biomarker and therapeutic approach.

e14016 Background: Glioblastoma is a lethal brain cancer. Clinical patterns of disease suggest that androgens influence glioblastoma risk and prognosis, and androgen receptor (AR) transcript levels and protein expression are upregulated in glioblastoma compared to normal brain. Thus, potent brain-penetrant anti-androgen therapies may be an effective treatment strategy in glioblastoma. Methods: Clinical samples and patient-derived glioma xenografts (PDXs) were assessed for AR expression by immunohistochemistry. Glioblastoma cell lines and patient-derived models maintained under stem cell conditions were tested in vitro for their response to anti-androgen therapies (abiraterone, enzalutamide and seviteronel). Change in plasticity marker ZEB1 was measured using immunofluorescence. Stem cell function was assessed using a tumoursphere assay. In an intracranial AR positive glioblastoma PDX model (RN1) in an immunocompromised mouse, the most effective drug in vitro, seviteronel, was tested alone and in combination with temozolomide or radiation. Tumor growth was monitored with weekly bioluminescent imaging, with survival as the primary endpoint. Results: Cytoplasmic AR staining was present in ~55% of glioblastoma samples using immunohistochemistry; this biomarker has shown to be predictive in triple-negative breast cancer. AR positive model RN1 was inhibited by low concentrations of anti-androgen agents, with seviteronel having the lowest half maximal inhibitory concentration (IC50) after 96 h (enzalutamide 52 µM, abiraterone 12 µM, seviteronel 7 µM). AR negative model WK1 was inhibited though with higher IC50 values after 96 h (enzalutamide 63 µM, seviteronel 21 µM). Cell lines U87 and U251 were also inhibited by anti-androgen monotherapy. Immunofluorescence analysis showed downregulation of plasticity marker ZEB1 with anti-androgens (normalized mean fluorescent intensity: abiraterone 0.84, enzalutamide 0.91, seviteronel 0.74). Tumoursphere assays demonstrated that anti-androgens inhibit the tumor-forming ability of cells, with seviteronel and abiraterone showing more inhibition than enzalutamide. In mice intracranially implanted with RN1 cells, seviteronel improved overall survival compared to vehicle alone (36 vs 27.5 days, p=0.03). There was no observed benefit when seviteronel was added to radiotherapy (33 vs 39 days, p=0.19). Adding seviteronel to temozolomide limited tumor growth by IVIS but did not significantly improve overall survival compared to temozolomide alone (63.5 vs 56.5 days, p=0.37). Conclusions: Targeting AR with brain penetrant anti-androgen drugs may be a promising biomarker-directed therapeutic strategy for glioblastoma. To address the limitations of our study, further experiments to optimize translational treatment protocols, address the role of biological sex and examine the role of the immune microenvironment are underway.

AR loss in prostate cancer stroma mediated by NF-κB and p38-MAPK signaling disrupts stromal morphogen production.

Androgen Receptor (AR) activity in prostate stroma is required to maintain prostate homeostasis. This is mediated through androgen-dependent induction and secretion of morphogenic factors that drive epithelial cell differentiation. However, stromal AR expression is lost in aggressive prostate cancer. The mechanisms leading to stromal AR loss and morphogen production are unknown. We identified TGFβ1 and TNFα as tumor-secreted factors capable of suppressing AR mRNA and protein expression in prostate stromal fibroblasts. Pharmacological and RNAi approaches identified NF-κB as the major signaling pathway involved in suppressing AR expression by TNFα. In addition, p38α- and p38δ-MAPK were identified as suppressors of AR expression independent of TNFα. Two regions of the AR promoter were responsible for AR suppression through TNFα. FGF10 and Wnt16 were identified as androgen-induced morphogens, whose expression was lost upon TNFα treatment and enhanced upon p38-MAPK inhibition. Wnt16, through non-canonical Jnk signaling, was required for prostate basal epithelial cell survival. These findings indicate that stromal AR loss is mediated by secreted factors within the TME. We identified TNFα/TGFβ as two possible factors, with TNFα mediating its effects through NF-κB or p38-MAPK to suppress AR mRNA transcription. This leads to loss of androgen-regulated stromal morphogens necessary to maintain normal epithelial homeostasis.

Lifespan Effects of Muscle-specific Androgen Receptor Overexpression on Body Composition of Male and Female Rats

Androgenic actions of gonadal testosterone are thought to be a major mechanism promoting sex differences in body composition across the lifespan. However, this inference is based largely on studies of androgen receptor (AR) function in late adolescent or emerging adult rodents. Here we assess body composition and quantify AR expression in skeletal muscle of rats at defined ages, comparing wild-type (WT) to transgenic HSAAR rats which overexpress AR in skeletal muscle. Male and female HSAAR and WT Sprague Dawley rats (N=288) underwent DEXA scanning and tissue collection at post-natal day (PND) 1, 10, 21, 42, 70, 183, 243, and 365. As expected, sex differences in body composition and muscle mass largely onset with puberty (PND-21), with no associated changes to skeletal muscle AR protein. In adulthood, HSAAR increased tibialis anterior (TA) and EDL mass in males, and reduced the expected gain in gonadal fat mass in both sexes. In WT rats, AR protein was reduced in soleus, but not TA, throughout life. Nonetheless, soleus AR protein expression was greater in males than females at all ages of sexual development, yet only at PND-70 in TA. Overall, despite muscle AR overexpression effects, results are inconsistent with major sex differences in body composition during sexual development being driven by changes in muscle AR, but rather suggest that changes in ligand promote sexual differentiation of body composition during pubertal timing. Nonetheless, increased skeletal muscle AR in adulthood can be suffcient to increase muscle mass in males, and reduce adipose in both sexes. This work was supported by an NSERC Grant awarded to D.A.M. (RGPIN 312458). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Abstract 5343: Depletion of gut microbiota with broad spectrum antibiotics drives Pten-null prostate cancer growth in mice

Abstract Gut microbes have the potential to be either promoters or inhibitors of cancer. Use of antibiotics during cancer therapy can lead to dysbiosis, which may affect treatment outcomes. Here, we examine the effects of broad-spectrum antibiotics on cancer progression in mice with Pten-null castration resistant prostate cancer (CRPC). After five or eight weeks, orchiectomized conditional Pten-null knockout (KO) mice aged 50 and 90 weeks were given two biweekly cycles of a broad-spectrum antibody cocktail (BSAbx), respectively. The effects of BSAbx on tumor burden were compared, and molecular and immunological responses were analyzed by quantitative IHC (qIHC) and qRt-PCR at week four after antibiotic treatment. BSAbx treatment resulted in tumor burdens of 1.2 and 2.4-fold higher than in control mice in mice aged 50 and 90 weeks, respectively. qIHC analysis of KI67 showed increased proliferation in stromal and cancer cells. Additionally, androgen receptor (AR) protein and gene expression levels of Ar and Ar target genes (Fkbp5, Tmprss2, and Timp4) were elevated in tumors of BSAbx-treated mice. Restoring gut microbiota by fecal microbiota transplantation (FMT) from KO mice CRPC after BSAbx restored AR transcriptional activity to basal levels and lessened tumor growth. FMT from non-castrated KO with castration-naïve prostate cancer or heathy wildtype mice further reduced AR Transcriptional activity. Moreover, altering the gut microbiota of CRPC mice with FMT from heathy mice resulted in a tendency for lower tumor burden, 21% reduction versus control mice. Immunologically, BSAbx treatment resulted in decreased CD11b+/GR1+ cells in tumors and were associated with decreased interferon-gamma (IFN-gamma), dendritic cell functions and T cell-mediated cytotoxicity gene signatures. Mice that received FMT form health mice showed enhanced T cell mediated immunity as demonstrated by higher IFN-gamma signatures and tumor abundances of CD8+ T cells expression IFN-gamma, TNF-alpha and the cytotoxic granule granzyme B. Our study shows that broad spectrum antibiotics caused dysbiosis and promoted prostate cancer growth in mice with Pten-null prostate cancer. The effects were partly mediated through the upregulation of AR signaling and the impairment of neutrophil and T cell-mediated immune responses in tumors. Citation Format: Marco A. De Velasco, Yurie Kura, Kazuko Sakai, Mitsuhisa Nishimoto, Yasunori Mori, Kazuhiro Yoshimura, Kazutoshi Fujita, Kazuto Nishio, Hirotsugu Uemura. Depletion of gut microbiota with broad spectrum antibiotics drives Pten-null prostate cancer growth in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5343.

Lifespan Effects of Muscle-Specific Androgen Receptor Overexpression on Body Composition of Male and Female Rats.

Androgenic actions of gonadal testosterone are thought to be a major mechanism promoting sex differences in body composition across the lifespan. However, this inference is based on studies of androgen receptor (AR) function in late adolescent or emerging adult rodents. Here we assess body composition and AR expression in skeletal muscle of rats at defined ages, comparing wild-type (WT) to transgenic human skeletal actin-driven AR overexpression (HSAAR) rats which overexpress AR in skeletal muscle. Male and female HSAAR and WT Sprague Dawley rats (N = 288) underwent dual-energy x-ray absorptiometry (DXA) scanning and tissue collection at postnatal day (PND) 1, 10, 21, 42, 70, 183, 243, and 365. Expected sex differences in body composition and muscle mass largely onset with puberty (PND-21), with no associated changes to skeletal muscle AR protein. In adulthood, HSAAR increased tibialis anterior (TA) and extensor digitorum longus mass in males, and reduced the expected gain in gonadal fat mass in both sexes. In WT rats, AR protein was reduced in soleus, but not TA, throughout life. Nonetheless, soleus AR protein expression was greater in male rats than female rats at all ages of sexual development, yet only at PND-70 in TA. Overall, despite muscle AR overexpression effects, results are inconsistent with major sex differences in body composition during sexual development being driven by changes in muscle AR, rather suggesting that changes in ligand promote sexual differentiation of body composition during pubertal timing. Nonetheless, increased skeletal muscle AR in adulthood can be sufficient to increase muscle mass in males, and reduce adipose in both sexes.

Design, synthesis, and biological evaluation of 2-(naphthalen-1-yloxy)-N-phenylacetamide derivatives as TRPM4 inhibitors for the treatment of prostate cancer

Transient receptor potential melastatin 4 (TRPM4) is considered to be a potential target for cancer and other human diseases. Herein, a series of 2-(naphthalen-1-yloxy)-N-phenylacetamide derivatives were designed and synthesized as new TRPM4 inhibitors, aiming to improve cellular potency. One of the most promising compounds, 7d (ZX08903), displayed promising antiproliferative activity against prostate cancer cell lines. 7d also suppressed colony formation and the expression of androgen receptor (AR) protein in prostate cancer cells. Furthermore, 7d can concentration-dependently induce cell apoptosis in prostate cancer cells. Collectively, these findings indicated that compound 7d may serve as a promising lead compound for further anticancer drug development.

STEM-03. TARGETING ANDROGEN SIGNALING IN GLIOBLASTOMA

Abstract BACKGROUND Glioblastoma is a lethal brain cancer. Androgen receptor (AR) transcript levels and protein expression are upregulated in glioblastoma compared to normal brain. AR signaling has a role in cancer stem cell function in various cancers. Stem cell activity and cancer cell plasticity represent a key resistance mechanism in glioblastoma. Thus, potent brain-penetrant anti-androgen therapies have the potential to improve treatment outcomes in glioblastoma. METHODS Clinical samples and patient derived xenografts were assessed for AR expression by immunohistochemistry. Cytoplasmic AR+ and AR- glioblastoma patient-derived xenografts maintained under stem cell conditions were tested in vitro for their response to anti-androgen therapies (abiraterone, enzalutamide and seviteronel). Stem cell function was assessed using a tumoursphere assay. Changes in plasticity markers, including ZEB1, were measured with immunofluorescence. RESULTS ~55% of people with glioblastoma have detectable cytoplasmic AR based on immunohistochemistry. AR-positive patient-derived glioma stem cell line RN1 was inhibited by low concentrations of anti-androgen agents, with seviteronel having the lowest half maximal inhibitory concentration (IC50) (at 96 hours: enzalutamide 52µM, abiraterone 12µM, seviteronel 7µM). AR-negative line WK1 was also inhibited though with higher IC50s (at 96 hours: enzalutamide 63µM, seviteronel 21µM). Conventional cell lines U87 and U251 were also inhibited by anti-androgen monotherapy. Tumoursphere assays demonstrated that anti-androgen agents inhibit the tumour-forming ability of cells, with seviteronel and abiraterone showing more inhibition than enzalutamide. Immunofluorescence analysis showed downregulation of plasticity marker ZEB1 with anti-androgen treatment (normalised mean fluorescent intensity: abiraterone 0.84, enzalutamide 0.91, seviteronel 0.74). CONCLUSIONS Glioblastoma is a devastating disease, lacking effective or targeted treatments. Targeting AR with repurposed anti-androgen drugs may be a promising therapeutic strategy, with the potential to abrogate treatment resistance. We are now evaluating these anti-androgen regimens in animal experiments, which will provide a more replicative microenvironment and confirm blood-brain barrier penetrance.

THU573 Paxillin Regulates Androgen Receptor In Granulosa Cells

Abstract Disclosure: A. Weidner: None. A. Roy: None. K. Vann: None. O. Astapova: None. Paxillin is a ubiquitously-expressed adaptor protein that is integral in focal adhesions and plays an active role in the regulation of cell motility and apoptosis. Recently, paxillin was shown to mediate pro-tumorigenic androgen signaling in prostate cancer cells, where it is necessary for rapid cytoplasmic kinase signaling triggered by activation of membrane-bound androgen receptor. We sought to investigate the relationship between paxillin and androgen receptor (AR) in granulosa cells, where androgen actions, apoptosis and focal adhesions are of known importance, but the role of paxillin is understudied. When paxillin expression was silenced using siRNA in human granulosa-derived KGN cells, AR protein expression was significantly reduced, while its RNA expression was unaffected. Similarly, in granulosa cell-specific paxillin knockout mice, AR protein expression in granulosa cells was reduced. Further, we found that AR and paxillin co-localize in focal adhesions in mouse primary granulosa cells and in KGN cells, and their interaction requires the activity of focal adhesion kinase. Disruption of focal adhesion with a focal adhesion kinase inhibitor also leads to reduced AR protein levels. To further explore the mechanisms by which paxillin regulates AR expression, we created paxillin-null KGN cell lines using CRISPR-Cas9 gene editing. While paxillin loss resulted in reduced AR protein expression early (days) in the gene-editing process, this effect disappeared after weeks of clonal expansion from selected single cells. Expanded paxillin-null KGN clones showed normal AR protein expression, but increased AR mRNA expression, suggesting an adaptive increase in AR gene transcription to compensate for reduced AR protein levels in cells that survived paxillin deletion. Studies of AR protein degradation using cycloheximide to block protein synthesis showed that the half-life of AR was reduced from 6.7 to 4.5 hours (approximately 33%) by paxillin deletion, indicating accelerated AR protein degradation in cells lacking paxillin. Based on our results, we hypothesize that paxillin brings AR into focal adhesions in granulosa cells, thereby sequestering it from proteasomal degradation in the cytoplasm. Thus, paxillin may be a novel target in the management of androgen-related disorders in women, such as polycystic ovary syndrome. Presentation Date: Thursday, June 15, 2023

SAT381 Effect of Obesity on Androgen-induced Splenic Dysregulation in Polycystic Ovary Syndrome

Abstract Disclosure: S. Rezq: None. J. Basnet: None. A.M. Huffman: None. L.L. Yanes Cardozo: None. D.G. Romero: None. Background: Polycystic ovary syndrome (PCOS) is characterized by ovarian dysfunction and hyperandrogenism. Women with PCOS exhibit low-grade systemic inflammation, obesity, and immune dysregulation. The spleen plays an important role in immune function and physiological inflammation regulation. Androgens and obesity negatively impact splenic structure and function. However, the effect of androgens on spleen architecture and function and its modulation by obesogenic diet is unknown in PCOS. Using a well-established PCOS model of hyperandrogenemia we aim to test the hypothesis that androgens cause splenic dysregulations that are exacerbated by obesity. Methods: Three-week-old female mice were treated with the androgen dihydrotestosterone (DHT, 8 mg, s.c) or vehicle. Animals were fed a high-fat diet (HFD; 60% kcal fat) or a low-fat diet (LFD; 10% kcal fat) for 90 days (n=6-8/group). Body composition (EchoMRI) and spleen weight were assessed. Splenic mRNA or protein expression of multiple immune cells/regulatory markers such as chemokines ligands Cxcl12 and Lymphotoxin B (Ltb), and their corresponding receptors C-X-C chemokine receptor type 4 (CXCR4) and Ltb receptor (LTBR), as well as the chemokine monocyte chemoattractant protein-1 (MCP-1), proliferation markers Csf1, Csf2, and Csf3, the adhesion molecule Vcam1, and extracellular matrix (ECM) remodeling marker Coch were assessed by RT-qPCR or Western blot. Additionally, splenic androgen receptor (AR) protein expression was measured by Western blot, while the inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor (TNF-α) were detected by ELISA. Results: DHT significantly (p<0.05) increased fat mass (6.2 ± 0.5 vs. 3.4 ± 0.3 g) and spleen weight (11.9 ± 1.6 vs. 4.9 ± 0.22 g) in LFD-fed mice, which was exacerbated by HFD. DHT-mediated splenomegaly was associated with a significant (p<0.05) decrease in the expression of AR (90%), the chemokine Cxcl12 (70-80%), the proliferation markers Csf1 and Csf2 (65-66%), and the ECM marker Coch (70%) in mice that were fed on both diets. PCOS mice had significantly (p<0.05) higher CXCR4 (4.4-4.7-fold) and LTBR (5.7-7.6-fold) expression, independent of diet. Interestingly, only the HFD-fed PCOS mice had significantly (p<0.05) lower splenic Vcam1 (76%), IL-6 (25%), and TNF-α (4.6 ± 0.2 vs. 5.6 ± 0.2 pg/μg protein) levels, while they also had higher MCP-1 protein levels (2-fold, p<0.05). Conclusion and significance: Our data show that androgens cause splenic structural and molecular alterations that are modulated by obesity. These findings could explain PCOS-associated immune dysregulation that is more predominant in obese women with PCOS. The study highlights the spleen as a novel key target organ of androgen-mediated pathology in PCOS. Furthermore, our study suggests that weight loss could potentially attenuate androgen-associated splenic derangements in PCOS. Presentation Date: Saturday, June 17, 2023

OR35-02 Novel Androgen Receptor PROTAC Degrader ARV-110 Ameliorates Androgen Mediated Renal Injury in a Mouse Model of Polycystic Ovary Syndrome

Abstract Disclosure: J. Basnet: None. S. Rezq: None. A.M. Huffman: None. T.E. Asala: None. L.L. Yanes Cardozo: None. D.G. Romero: None. Background: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in reproductive-age women. PCOS women often have increased central adiposity, insulin resistance, and renal injury. Hyperandrogenism is prevalent in PCOS women and is associated with renal injury and dysfunction. Androgens bind to the androgen receptor (AR) to impart downstream transcriptional activity. Targeting the AR may alleviate PCOS complications; however, the use of AR blockers is limited by their severe adverse effects in females; thus, safer alternative approaches are highly needed. The novel AR Proteolysis Targeting Chimera (PROTAC) degrader ARV-110 has shown high efficacy to prevent AR signaling in prostate cancer; however, its efficacy in PCOS is unknown. Using a well-established hyperandrogenemic mouse model of PCOS, we aim to test the hypothesis that decreasing AR protein levels with ARV-110 ameliorates androgen-mediated derangements in PCOS. Methods: Three-week old female mice (C57BL/6N) were implanted with Silastic tubes filled with the androgen dihydrotestosterone (DHT, 8mg, s.c., 90 days) or vehicle (n=6/grp). Four weeks post-DHT administration, mice were treated with ARV-110 (1 mg/kg/day, s.c.) for an additional 8 weeks. Body composition (EchoMRI) and oral glucose tolerance test (OGTT) were assessed. Kidney weight was measured by gravimetry. AR, extracellular matrix (ECM) remodeling marker MMP9, pro-fibrotic marker TGF-β, renal injury markers (urinary albumin to creatinine ration (UACR), KIM1, and NGAL) were assessed by Western-blot or ELISA. Results: DHT mice showed significant (p<0.05) increases in body weight (27.3±0.6 vs 23.9±0.26 g), fat mass (4.2±0.6 vs 2.1±0.1 g), lean mass (21.6±0.2 vs 19.8±0.2 g), as well as kidney weight (491.3±7.69 vs 303.1±5.5 mg) compared to controls. DHT increased fasting glucose (183.2±25.2 vs 141.5±9.9 mg/dL, p<0.05) and impaired OGTT (AUC:34557±6255 vs 23459±1896 mg.min/dL, p<0.05). ARV-110 treatment ameliorated all aforementioned DHT-mediated changes. At the molecular level, DHT-treated mice had higher renal AR (2.5-fold) and MMP9 (1.5-fold) protein expression. DHT upregulated renal TGF-β levels (2-fold, p<0.05), UACR (966.8±160.9 vs 381.5±41.2 ng albumin/mg creatinine), and urinary KIM1 (3.5-fold) and NGAL (6-fold). ARV-110 successfully decreased renal AR protein levels by 70% in DHT mice compared to vehicle-treated DHT. Excitingly, while ARV-110 did not modulate renal TGF-β levels, it completely abolished DHT-mediated increase in renal MMP9 while significantly lowering the levels of urinary renal injury markers UACR, KIM1 and NGAL. Conclusion and significance: Our findings suggest that DHT-mediated kidney hypertrophy, associated ECM remodeling and injury are ameliorated by ARV-110 in DHT-treated mice. AR PROTACs could be a novel therapeutic approach to treat renal dysfunction in PCOS. Supported by NIH P20GM121334. Presentation Date: Sunday, June 18, 2023

Luteolin inhibits A549 cells proliferation and migration by down-regulating androgen receptors

BackgroundYi Fei Qing Hua Granules (YQG) is a traditional Chinese herbal medicine with the effects of inhibiting the proliferation of lung cancer cells. Luteolin is one of the active compounds of YQG. Luteolin is a common flavonoid extracted from natural herbs and it can promote cancer cells apoptosis has been reported. However, the underlying molecular mechanism and effects of luteolin on human lung cancer needs to be validated.MethodsMolecular docking, network pharmacology methods and quantitative structure–activity relationship (QSAR) model were used to identify the active components of YQG and their possible mechanisms of action. Western blot analysis was used to measure AR expression in A549 cells. Cell migration assays were used to detect A549 cells proliferation transfected by AR plasmid and AR mutation plasmid, respectively.ResultsTCMSP search results revealed that there are 182 active compounds in YQG, which correspond to 232 target genes. Sixty-one genes were overlapping genes in the 2 datasets of TCMSP and GeneCards. Through bioinformatics tagging of these overlapping genes, a total of 1,951 GO functional tagging analysis and 133 KEGG pathways were obtained. Through molecular docking technology and QSAR model verification, the multi-target active compound luteolin was screened out as one of the active components of YQG for in vitro verification. Androgen receptor (AR) was the hub protein with the highest docking score of luteolin. Western blot showed that luteolin could inhibit AR protein expression in lung cancer cell line A549. After the phosphorylation site of AR protein 877 was inactivated, the ability of luteolin to inhibit the proliferation of lung cancer cells was weakened. Luteolin significantly inhibited the growth of A549 xenogeneic tumors at day 25 and 28 and inhibited the expression of AR.ConclusionIn this study, we have explored luteolin as one of the active components of YQG, and may inhibit the proliferation and migration of A549 cells by decreasing the expression of AR and the regulation of phosphorylation at AR-binding sites.

Effects of Xihuang Pills on proliferation and apoptosis of prostate cancer LNCaP cells based on AR/m TOR signaling pathway

Based on the androgen receptor(AR)/mammalian target of rapamycin(mTOR)signaling pathway, the effects of Xihuang Pills-medicated serum on the proliferation and apoptosis of prostate cancer LNCaP cells were investigated. The drug-containing serum of SD rats was prepared by intragastric administration of Xihuang Pills suspension. The effects of low-, medium-, and high-dose Xihuang Pills-containing serum on the in vitro proliferation of LNCaP cells were detected by cell counting kit-8(CCK-8). Flow cytometry was used to detect the apoptosis level of LNCaP cells after intervention with different concentrations of Xihuang Pills. Protein expression of cleaved cysteinyl aspartate-specific proteinase caspase-3(cleaved caspase-3), B-cell lymphoma-2(Bcl-2), and AR as well as the phosphorylation level of mTOR protein were detected by Western blot. The results showed that compared with the blank serum, the drug-medicated serum could blunt the activity of LNCaP cells. Low-, medium-, and high-dose Xihuang Pills-containing serum could significantly increase the cell apoptosis rate, increase the expression of cleaved caspase-3 protein, decrease the expression of Bcl-2 protein, reduce the expression of AR protein, and down-regulate the level of phosphorylated mTOR(p-mTOR). To study the effect of Xihuang Pills on the growth of LNCaP cells in vivo, different doses of Xihuang Pills were used to intervene in the subcutaneous graft model in nude mice inoculated with LNCaP cells. The expression levels of AR, mTOR, p-mTOR, Bcl-2, and cleaved caspase-3 were detected by Western blot. The results showed that the volumes of subcutaneous graft tumor in the low-dose, medium-dose, and high-dose Xihuang Pills groups significantly decreased compared with that in the model group. The weight of subcutaneous transplanted tumor in each group with drug intervention was significantly lower than that in the model group. Compared with the model group, the low-dose, medium-dose, and high-dose Xihuang Pills groups showed increased cleaved caspase-3 protein expression, decreased Bcl-2 and AR protein expression, and reduced p-mTOR protein expression. Further experiments showed that AR agonist R1881 could block the anti-proliferation and pro-apoptotic effects of Xihuang Pills. The mechanism of Xihuang Pills against prostate cancer is related to the inhibition of the AR/mTOR signaling pathway, inhibition of LNCaP cell proliferation, and induction of apoptosis in cancer cells.

Triple-negative Breast Carcinoma With Apocrine and Histiocytoid features: A Clinicopathologic and Molecular Study of 18 Cases.

Triple-negative breast cancer (TNBC) is a heterogenous group of tumors. Most TNBCs are high-grade aggressive tumors, but a minority of TNBCs are not high grade, with relatively indolent behavior and specific morphologic and molecular features. We performed a clinicopathologic and molecular assessment of 18 non-high-grade TNBCs with apocrine and/or histiocytoid features. All were grade I or II with low Ki-67 (≤20%). Thirteen (72%) showed apocrine features, and 5 (28%) showed histiocytoid and lobular features. In all, 17/18 expressed the androgen receptor, and 13/13 expressed gross cystic disease fluid protein 15. Four (22.2%) patients were treated with neoadjuvant chemotherapy, but none achieved a pathologic complete response. In all, 2/18 patients (11%) had lymph node metastasis at the time of surgery. None of the cases had a recurrence or disease-specific death, with an average follow-up time of 38 months. Thirteen cases were profiled by targeted capture-based next-generation DNA sequencing. Genomic alterations (GAs) were most significant for PI3K-PKB/Akt pathway (69%) genes, including PIK3R1 (23%), PIK3CA (38%), and PTEN (23%), and RTK-RAS pathway (62%) including FGFR4 (46%) and ERBB2 (15%). TP53 GA was seen in only 31% of patients. Our findings support those on high-grade TNBCs with apocrine and/or histiocytoid features as a clinicopathologic and genetically distinct subgroup of TNBC. They can be defined by features including tubule formation, rare mitosis, low Ki-67 (≤20%), triple-negative status, expression of androgen receptor and/or gross cystic disease fluid protein 15, and GA in the PI3K-PKB/Akt and/or RTK-RAS pathway. These tumors are not sensitive to chemotherapy but have favorable clinical behavior. Tumor subtype definitions are the first step to implementing future trial designs to select these patients.

Abstract B008: Tumor-stromal 3D co-cultures to study the role of cancer-associated fibroblasts in the acquisition of androgen-deprivation therapy resistance in prostate cancer

Abstract Introduction and Objective Several studies have shown that cancer-associated fibroblasts (CAFs), the most abundant component in prostate cancer (PCa) microenvironment, promote resistance to androgen deprivation therapies, and metastatic development. The aim of this study is to elucidate the mechanisms of CAF-induced therapy resistance through the establishment of in vitro 3D co-cultures. Methods In this study, the androgen-dependent PNPCa patient-derived xenograft (PDX) model (derived from soft tissue metastasis), and the androgen-independent LAPC9 PDX model (bone metastasis) are used. Epithelial and stromal cells (human and mouse origin, respectively) are separated through magnetic-associated cell sorting to generate PDX-derived organoids and fibroblasts. Fibroblast RNA and protein expression is assessed through RT-qPCR, Western Blot, and Immunofluorescence. Direct 3D co-cultures are obtained by combining fluorescently labelled organoids and fibroblasts in ultra-low attachment plates in defined media. In indirect co-cultures, organoids are cultured in Spherical Plates (Kugelmeiers) with fibroblasts on transwell inserts. Organoid viability is measured after 9 days by CellTiter-Glo 3D Assay. Results PDX-derived fibroblasts express typical CAF genes (e.g. α-smooth muscle actin and Tenascin C), and androgen receptor (AR), both at RNA and protein level. AR protein expression (as well as RNA expression of the AR target gene Fkbp5) is increased in CAFs upon treatment with dyhydrotestosterone (DHT) 10nM, while co-treatment with the AR inhibitor Enzalutamide 10mM abrogates this effect, suggestive of functional AR signaling. These CAFs can organize into tumor/CAF organoid 3D structures upon combination with PDX-derived tumor epithelial cells, providing an in vitro functional model to study tumor-stromal interactions. In indirect (transwell) co-cultures, CAFs increase the viability of the androgen dependent PNPCa organoids, but not that of androgen independent LAPC9. This growth-promoting effect is observed even upon culturing of PNPCa organoids in non-optimal growth conditions, at low DHT concentrations (DHT 0.5nM and 0.25nM versus the standard DHT 1nM). The factors mediating this process will be identified by gene expression profiling of CAFs and organoids in transwell co-cultures and/or monoculture. Conclusions Our data indicate that PCa metastatic cells modify the properties of neighbor stromal cells to support tumorigenesis, since PDX-derived fibroblasts, originally part of the mouse dermal stroma, display CAF features and active AR signaling. 3D co-cultures represent a useful tool to study the tumor-stromal interactions. Our transwell co-culture experiments suggest that CAFs play an important role in supporting the viability and growth of early metastatic androgen dependent PCa cells (PNPCa) by secreting pro-tumorigenic factors. The possibility that CAFs exert different effects depending on the tumor stage setting (early vs advanced) will be subsequently investigated. Citation Format: Francesco Bonollo, Natalie Sampson, George Thalmann, Sofia Karkampouna, Marianna Kruithof-de Julio. Tumor-stromal 3D co-cultures to study the role of cancer-associated fibroblasts in the acquisition of androgen-deprivation therapy resistance in prostate cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Prostate Cancer Research; 2023 Mar 15-18; Denver, Colorado. Philadelphia (PA): AACR; Cancer Res 2023;83(11 Suppl):Abstract nr B008.

X-linked SBMA model mice display relevant non-neurological phenotypes and their expression of mutant androgen receptor protein in motor neurons is not required for neuromuscular disease

X-linked spinal and bulbar muscular atrophy (SBMA; Kennedy's disease) is a rare neuromuscular disorder characterized by adult-onset proximal muscle weakness and lower motor neuron degeneration. SBMA was the first human disease found to be caused by a repeat expansion mutation, as affected patients possess an expanded tract of CAG repeats, encoding polyglutamine, in the androgen receptor (AR) gene. We previously developed a conditional BAC fxAR121 transgenic mouse model of SBMA and used it to define a primary role for skeletal muscle expression of polyglutamine-expanded AR in causing the motor neuron degeneration. Here we sought to extend our understanding of SBMA disease pathophysiology and cellular basis by detailed examination and directed experimentation with the BAC fxAR121 mice. First, we evaluated BAC fxAR121 mice for non-neurological disease phenotypes recently described in human SBMA patients, and documented prominent non-alcoholic fatty liver disease, cardiomegaly, and ventricular heart wall thinning in aged male BAC fxAR121 mice. Our discovery of significant hepatic and cardiac abnormalities in SBMA mice underscores the need to evaluate human SBMA patients for signs of liver and heart disease. To directly examine the contribution of motor neuron-expressed polyQ-AR protein to SBMA neurodegeneration, we crossed BAC fxAR121 mice with two different lines of transgenic mice expressing Cre recombinase in motor neurons, and after updating characterization of SBMA phenotypes in our current BAC fxAR121 colony, we found that excision of mutant AR from motor neurons did not rescue neuromuscular or systemic disease. These findings further validate a primary role for skeletal muscle as the driver of SBMA motor neuronopathy and indicate that therapies being developed to treat patients should be delivered peripherally.

Abstract A073: Human prostate-on-chip models to define stromal and epithelial interactions in normal and cancerous prostate

Abstract Background: The secretion of morphogenic factors from the stroma, whose production is dependent on stromal androgen receptor (AR) action, is crucial for maintaining glandular structure and homeostatic function of the prostate gland. However, the precise nature of the factors involved, their regulation, and how they impact homeostasis in the human prostate is not clear. We hypothesize that loss of stromal AR function as seen in prostate cancer progression and during androgen-deprivation therapy likely contribute to tumor progression through disruption of this homeostasis. It is important to understand these interactions in the human context to better aid in improving patient outcomes. Approach: Microfluidic-based technology was used to develop the first human Prostate-on-Chip (PoC) where human prostate fibroblasts are co-cultured with human prostate basal epithelial cells under flow. Addition of androgen to the stromal cells is sufficient to induce luminal cell differentiation on top of the neighboring basal cells – recapitulating the cellular architecture of the human gland. To study prostate cancer in this context, we replaced the normal epithelial cells with tumor cells to interrogate the tumor-stromal interactions; thus, generating a human Prostate Cancer-on-Chip model (PCoC). Cytokine arrays and RT-qPCR was used to identify androgen-induced stromal morphogens and tumor cytokines involved in tumor/stromal interactions. Molecular biology approaches were used to identify the mechanisms involved. Results: Within the PCoC model, tumor cells invaded into the stroma and conversely stromal cells invaded into the tumors. This was accompanied by localized CAF conversion of the stroma. Invasion of tumor cells into the stroma could be blocked with an integrin-α6 binding peptide. Strikingly, the level of AR expression in the stroma was also reduced, recapitulating the loss of stromal AR expression seen in patients. A cytokine array identified TNFα and TGFβ as tumor secreted factors responsible for suppressing stromal AR protein and mRNA expression. TNFα suppressed stromal AR expression in the absence of CAF conversion via NF-κB binding to the AR promoter. On the other hand, p38-MAPK signaling suppressed AR expression independent of TNFα. FGF10 and Wnt16, but not KGF, were identified as androgen-induced stromal secreted morphogens. Loss of stromal AR expression, led to suppression of FGF10 and Wnt16, but not KGF expression. Thus, stromal AR inhibition by tumor secreted TNFα or p38-MAPK signaling suppresses the stromal morphogens required to maintain normal prostate homeostasis. Conclusions: We have developed the first human Prostate-on-Chip and Prostate Cancer-on-Chip models which recapitulate the biology of both the normal human prostate as well as prostate cancer stromal interactions. These models can be used to address a range of clinical problems in cancer development, drug response, and biomarker identification in the context of the tumor microenvironment. This model can easily be adapted for personalized medicine approaches. Citation Format: Shekha K. Tahsin, Linan Jiang, Neha Sane, Kailie Szewczyk, Hunain Khawaja, Yitshak Zohar, Cindy K. Miranti. Human prostate-on-chip models to define stromal and epithelial interactions in normal and cancerous prostate [abstract]. In: Proceedings of the AACR Special Conference: Advances in Prostate Cancer Research; 2023 Mar 15-18; Denver, Colorado. Philadelphia (PA): AACR; Cancer Res 2023;83(11 Suppl):Abstract nr A073.

Deep multi-omic analyses to identify targetable pathways in desmoplastic small round cell tumor (DSRCT) with opportunities for clinical intervention.

e22006 Background: DSRCT is an extremely rare and highly aggressive soft-tissue sarcoma affecting adolescents and young adults with male predominance. The 5-year overall survival is < 25% despite intensive multi-modality treatment including aggressive surgical resection, radiotherapy, chemotherapy, and targeted therapy. Therefore, more effective and innovative therapeutic options are urgently needed. Recent advances in genomic, epigenomic, proteomic, and immune profiling have uncovered a large number of therapeutic targets that are transforming the field of cancer medicine. This study aimed to identify novel targetable pathways in DSRCT using a deep multi-omics-based platform. Methods: Three patients with biopsy proven metastatic DSRCT were enrolled under an IRB-approved observational study within the “Serial Measurements of Molecular and Architectural Responses to Therapy” (SMMART) program at OHSU. Biopsies taken at enrollment were analyzed with targeted DNA sequencing, whole transcriptome sequencing, immunohistochemistry (IHC), NanoString GeoMx digital spatial profiling (DSP) multiplexed proteomics, single cell cyclic immunofluorescence (Cyc-IF), and reverse phase protein array (RPPA). Results: Multiple clinically relevant targets were identified, including HER2, androgen receptor (AR), elevated DNA damage response, and MAPK and mTOR signaling pathways. All three DSRCTs expressed HER2: clinical IHC identified HER2 low (1+) to HER2 equivocal (2+) expression; DSP analysis showed high HER2 and phospho-HER2 expression; and HER2 RNA expression was elevated compared to the TCGA sarcoma cohort. Two of the three patients displayed high AR protein expression, assessed by clinical IHC (90-100% positive cells) and DSP (top quartile compared to a 20 mixed-subtype breast cancer cohort). Strong evidence of DNA damage response was demonstrated at both RNA and protein levels, and RPPA revealed high PARP1, PAR, p-ATM, p-RPA32, and RAD51. Within cell signaling pathways, one DSRCT exhibited high total and phospho-ERK1/2 protein across all clinical and exploratory assays, while another patient displayed evidence of elevated mTOR pathway signaling by RPPA. Conclusions: Overall, this multi-omic analysis provided new insights into possible therapeutic targets for this rare and difficult to treat sarcoma subtype. Results from this study will be further validated in vivo using patient-derived xenograft (PDX) models, providing support for development of multiple early phase trials.

Impacts of androgen pathway manipulation on patients with lung cancer.

e21010 Background: Sex hormone may play a role in lung cancer pathophysiology. We aimed to evaluate if androgen pathway manipulation (APM) is associated with better survival in patients with lung cancer, and how finasteride, a 5-alpha reductase inhibitor, impacts androgen receptor (AR) activation and growth of lung cancer cells. Methods: In this retrospective hospital-based cohort study, we screened all men with lung cancer diagnosed during the period from January 2006 to December 2021. APM exposure was defined as using antiandrogens, 5-alpha reductase inhibitors, or gonadotropin-releasing hormone agonists for > 30 days after lung cancer diagnosis. The in vitro study was conducted on A549 lung cancer cells; while the tumor xenograft model was conducted on BALB/c nude mice. Results: Among 4744 men with lung cancer, 98 (2.1%) were identified as having APM exposure. The majority of patients (73.5%) received 5-alpha reductase inhibitors. The patients with APM exposure were older (71.5 vs. 67.0, p < 0.001), had a higher proportion of having prostate cancer (27.6% vs. 1.4%, p < 0.001), and had a smaller proportion of having metastatic lung cancer (41.8% vs. 54.0%, p = 0.003), compared to those without APM exposure. In multivariable Cox proportional hazards analysis, patients with APM exposure experienced better OS compared to those without exposure (Hazard ratio 0.57; 95% CI, 0.44–0.73, p < 0.001). In in vitro study, we illustrated that AR protein stimulated the cell proliferation of A549 cells. Finasteride reduced the AR protein expression and inhibited A549 cell growth. Finasteride promoted ubiquitination and degradation of AR protein and therefore interfered the stability of AR protein. Furthermore, finasteride inhibited cell cycle progression and promoted apoptosis of A549 cells. The in vivo results also supported the inhibition effect of finasteride on lung cancer growth. Conclusions: APM was associated with better OS in male patients with lung cancer. Finasteride interfered with the stability of AR and inhibited A549 lung cancer cell growth. Our findings indicated an oncogenic role of AR on lung cancer which may provide potential therapeutic and targets for lung cancer. The inhibition effect of finasteride on lung cancer might be of benefit for future treatment strategies, prevention and control.[Table: see text]