Low Androgen Receptor Expression Research Articles

The prognostic significance of androgen receptor expression in gliomas

Androgen receptor (AR) overexpression has been identified in gliomas and its stem cells, suggesting that AR plays an important role in tumor carcinogenesis. The prognostic significance of AR overexpression in gliomas remains unknown. AR mRNA expression in gliomas and relevant clinical data were obtained from The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases. AR expression levels were compared across gliomas of different histopathologic grades and molecular subtypes. Kaplan–Meier analyses in patients with different AR expression levels were investigated for the potential prognostic values of AR. Compared with normal brain tissue, gliomas show significantly higher AR mRNA expression (p < 0.01). AR mRNA expression was more prominent in higher grade disease and in worse prognostic molecular subtypes (p < 0.01). AR protein is more abundant in glioblastoma than in lower grade gliomas (LGG) (grade 2/3) (p < 0.0001). This is corroborated by a linear association between AR mRNA and protein expression (r = 0.65). In LGG, both higher AR mRNA and protein expression was associated with significantly worse overall survival (OS). Five-year OS for LGG patients with high versus low AR expression were 59.1% and 73.3%, respectively (p < 0.0001). AR expression is not prognostic for OS within glioblastoma patients. Gender was not associated with AR expression or prognosis. Higher AR expression levels are associated with higher grade disease and histopathologic features predicting poorer prognosis in lower grade gliomas. Higher gene expression in LGG patients is correlated with poor prognosis but not in the glioblastoma cohort suggesting saturated expression/functions of AR in glioblastoma.

Prostate-Specific Membrane Antigen-Targeted Imaging and Its Correlation with HOXB13 Expression.

Homeobox 13 (HOXB13) is an oncogenic transcription factor that directly regulates expression of folate hydrolase 1, which encodes prostate-specific membrane antigen (PSMA). HOXB13 is expressed in primary and metastatic prostate cancers (PCs) and promotes androgen-independent PC growth. Since HOXB13 promotes resistance to androgen receptor (AR)-targeted therapies and regulates the expression of folate hydrolase 1, we investigated whether SUVs on PSMA PET would correlate with HOXB13 expression. Methods: We analyzed 2 independent PC patient cohorts who underwent PSMA PET/CT for initial staging or for biochemical recurrence. In the discovery cohort, we examined the relationship between HOXB13, PSMA, and AR messenger RNA (mRNA) expression in prostate biopsy specimens from 179 patients who underwent PSMA PET/CT with 18F-piflufolastat. In the validation cohort, we confirmed the relationship between HOXB13, PSMA, and AR by comparing protein expression in prostatectomy and lymph node (LN) sections from 19 patients enrolled in 18F-rhPSMA-7.3 PET clinical trials. Correlation and association analyses were also used to confirm the relationship between the markers, LN positivity, and PSMA PET SUVs. Results: We observed a significant correlation between PSMA and HOXB13 mRNA (P < 0.01). The association between HOXB13 and 18F-piflufolastat SUVs was also significant (SUVmax, P = 0.0005; SUVpeak, P = 0.0006). Likewise, the PSMA SUVmax was significantly associated with the expression of HOXB13 protein in the 18F-rhPSMA-7.3 PET cohort (P = 0.008). Treatment-naïve patients with LN metastases demonstrated elevated HOXB13 and PSMA levels in their tumors as well as higher PSMA tracer uptake and low AR expression. Conclusion: Our findings demonstrate that HOXB13 correlates with PSMA expression and PSMA PET SUVs at the mRNA and protein levels. Our study suggests that the PSMA PET findings may reflect oncogenic HOXB13 transcriptional activity in PC, thus potentially serving as an imaging biomarker for more aggressive disease.

Abstract 7344: Role of ubiquitin receptor ADRM1 (Rpn13) in prostate cancer

Abstract Adhesion-regulating molecule 1 (ADRM1)/Rpn13 is a component of the 19S regulatory subunit of the 26S proteasome [1]. ADRM1 plays a crucial role in the recognition of polyubiquitinated substrates of the proteasome and their subsequent deubiquitination and degradation [2]. ADRM1 transcript levels are commonly upregulated in diverse tumor types [3]. The androgen receptor (AR) plays a predominant role in prostate cancer (PCa) pathology. In this study, we investigated the expression of ADRM1/Rpn13 in different stages of prostate cancer and its association with AR expression. TCGA data from UALCAN was used for understanding ADRM1 expression on different stages of diseases and single-cell RNA-sequencing data of prostate cancer cell line was obtained from Prostate Cancer Atlas. TCGA (cell, 2015) data set was used for investigating the correlation between ADRM1 and AR by using R programming. Our study from the TCGA dataset reveals that ADRM1 expression increased significantly with the aggressiveness of prostate cancer (increase consistently with the Gleason score) from the TCGA dataset. We analyzed ADRM1 and AR expression in different prostate cancer cell lines and obtained that ADRM1 expressed significantly higher in prostate cancer cell lines which had lower AR expression. TCGA (cell, 2015) dataset indicated a negative correlation between ADRM1 and AR expression in prostate cancer. Our preliminary analysis indicated that ADRM1 inhibitor might be a potential therapeutic option for AR-independent prostate cancer. Citation Format: Shahjalal Chowdhury, Honghe Wang, Chitra Nayak, Balasubramanyam Karanam. Role of ubiquitin receptor ADRM1 (Rpn13) in prostate cancer [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 7344.

Transcriptomic Analysis to Uncover the Mechanism of Radiosensitization of AR-Positive Triple Negative Breast Cancers with AR Inhibition

The androgen receptor (AR) has been shown to drive tumor growth in triple negative breast cancers (TNBC), and previous work demonstrated AR inhibition as a strategy for radiosensitization in AR-positive (AR+) TNBC. Despite its role in radioresistance, the mechanistic role of AR in response to radiation therapy (RT) remains unknown, as does the benefit of 2nd generation anti-androgens in this context. We hypothesized that all 2nd generation anti-AR therapy would radiosensitize similarly and that canonical AR transcriptional function was responsible for radioresistance in these models. Radiosensitization was assessed using 2nd generation AR antagonists (apalutamide, enzalutamide, and darolutamide) using clonogenic survival assays in MDA-MB-453, SUM185, MFM-223, and MDA-MB-231 cells at 2-6Gy. Cellular fractionation experiments were performed and quantitated to determine the location of the AR protein in cells treated with AR agonists +/- RT. RNA Seq was performed and transcriptomic approaches were used (Advaita iPathway analysis) to investigate AR-mediated effects in response to RT. Inhibition with the 2nd generation anti-androgens enzalutamide and apalutamide is sufficient to radiosensitize AR+ TNBC models (rER: 1.34-1.41); while darolutamide had no effect on radiosensitivity (rER: 0.96-1.11). Additionally, TNBC cells with low AR expression were not radiosensitized by AR inhibition with any drug (rER: 0.96-1.03). While stimulation with the synthetic androgen methyltrienolone R1881 is sufficient to induce nuclear translocation of AR in AR+ TNBC cells, AR inhibition with enzalutamide, apalutamide, or darolutamide blocked AR nuclear translocation under growth conditions with charcoal stripped serum or fetal bovine serum. When cells are treated with R1881+RT, nuclear translocation of AR was induced at similar or greater levels compared to R1881 alone in AR+ TNBC cells. Combination treatment of RT with enzalutamide in the presence of hormones reduced nuclear localization of AR (32-39% reduction) compared to RT alone. RNA-sequencing after RT identified transcriptional changes potentially regulated by AR+RT, including changes in the NHEJ pathway genes. Additionally, pathway analyses in these models demonstrated changes in the MAPK/ERK signaling pathway, among others, that may regulate RT resistance in AR+ TNBC models. Most 2nd generation anti-androgens confer radiosensitization in AR+ TNBC models with cellular localization changes of AR noted after RT. The known structural differences amongst 2nd generation anti-androgens may account for differences in radiosensitization noted. Furthermore, AR-mediated radioresistance may be due, at least in part, to downstream MAPK/ERK signaling. This work builds on the mechanistic understanding of AR-mediated radioresistance in AR+ TNBC and may expose vulnerabilities to overcome resistance to combination treatment with AR inhibition and RT.

Predictive factors associated with differential pathologic response to neoadjuvant chemohormonal therapy in high-risk localized prostate cancer

To explore the clinical parameters and molecular biomarkers that can predict differential pathologic response to neoadjuvant chemohormonal therapy (NCHT) in prostate cancer (CaP).A total of 128 patients with primary high-risk localized CaP who had received NCHT followed by radical prostatectomy (RP) were included. Androgen receptor (AR), AR splice variant-7 (AR-V7) and Ki-67 staining were evaluated in prostate biopsy specimens by immunohistochemistry. The pathologic response to NCHT in whole mount RP specimens was measured based on the reduction degree of tumor volume and cellularity compared to the paired pretreatment needle biopsy, and divided into 5 tier grades (Grades 0-4). Patients with Grades 2 to 4 (the reduction degree more than 30%) were defined as having a favorable response. Logistic regression was performed to explore the predictive factors associated with a favorable pathologic response. The predictive accuracy was evaluated by receiver operating characteristic (ROC) curve and area under the ROC curve (AUC).Ninety-seven patients (75.78%) had a favorable response to NCHT. Logistic regression showed that the preoperative PSA level, low AR expression and high Ki-67 expression in biopsy specimens were associated with a favorable pathologic response (P < 0.05). Furthermore, the AUC of the preoperative PSA level, AR and Ki-67 were 0.625, 0.624 and 0.723, respectively. Subgroup analysis revealed that the rate of favorable pathologic response to NCHT was 88.5% in patients with ARlowKi-67high, which was higher than patients with ARlowKi-67low, ARhighKi-67low, and ARhighKi-67high (88.5% vs. 73.9%, 72.9%, and 70.9%, all P < 0.05).A lower preoperative PSA level was an independent predictive factor for a favorable pathologic response. Moreover, the expression status of AR and Ki-67 in biopsy specimens were associated with differential pathologic response to NCHT, and AR low/Ki-67 high was also associated with favorable response but warrants further evaluation in this patient subgroup and future trial clinical trial design.

Therapeutic blocking of VEGF binding to neuropilin-2 diminishes PD-L1 expression to activate antitumor immunity in prostate cancer.

Prostate cancers are largely unresponsive to immune checkpoint inhibitors (ICIs), and there is strong evidence that programmed death-ligand 1 (PD-L1) expression itself must be inhibited to activate antitumor immunity. Here, we report that neuropilin-2 (NRP2), which functions as a vascular endothelial growth factor (VEGF) receptor on tumor cells, is an attractive target to activate antitumor immunity in prostate cancer because VEGF-NRP2 signaling sustains PD-L1 expression. NRP2 depletion increased T cell activation in vitro. In a syngeneic model of prostate cancer that is resistant to ICI, inhibition of the binding of VEGF to NRP2 using a mouse-specific anti-NRP2 monoclonal antibody (mAb) resulted in necrosis and tumor regression compared with both an anti-PD-L1 mAb and control immunoglobulin G.This therapy also decreased tumor PD-L1 expression and increased immune cell infiltration. We observed that the NRP2, VEGFA, and VEGFC genes are amplified in metastatic castration-resistant and neuroendocrine prostate cancer. We also found that individuals with NRP2High PD-L1High metastatic tumors had lower androgen receptor expression and higher neuroendocrine prostate cancer scores than other individuals with prostate cancer. In organoids derived from patients with neuroendocrine prostate cancer, therapeutic inhibition of VEGF binding to NRP2 using a high-affinity humanized mAb suitable for clinical use also diminished PD-L1 expression and caused a substantial increase in immune-mediated tumor cell killing, consistent with the animal studies. These findings provide justification for the initiation of clinical trials using this function-blocking NRP2 mAb in prostate cancer, especially for patients with aggressive disease.

Abstract 5563: Androgen receptor (AR) is frequently found in human cancers and inversely linked to patient outcome in breast and renal cell carcinomas

Abstract Background: Androgen receptor (AR) is a nuclear transcription regulator which mediates the growths stimulating effect of androgens. Inhibition of AR signaling is the most important first line therapy in prostate cancer. Clinical trials are ongoing for molecularly defined subsets of breast cancers expressing AR. In surgical pathology, AR immunohistochemistry is used as a marker for prostate cancer. Design: To comprehensively determine AR expression in normal and neoplastic tissues, a tissue microarray containing 18,234 samples from 141 different tumor types and subtypes as well as 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry. Results: AR positivity was found in 116 of 141 tumor categories, and 66 of these tumor categories contained at least one case with strong AR staining. AR positivity was most seen in different categories of prostate cancer (87.8-100%), various subtypes of breast cancer (34.3-94.9%) and ovarian cancers (48.7-97.1%), in endometrial cancers (53-61.1%), salivary duct carcinomas (70%), teratomas (60%), renal cell carcinomas (41.8-62.7%), urinary bladder cancers (43.2-48.7%), granular cell tumors (40.7%), leiomyosarcomas (33.3%), gastrointestinal stroma tumors (31.1%) and urothelial carcinomas of the kidney pelvis (30.4%). Seventy-seven additional tumor types showed AR expression in up to 30% of the analyzed samples, but AR expression was typically only weak in these tumors. Among 1,430 evaluable invasive breast carcinomas of no special type (NST), absent or low AR immunostaining was significantly linked to high BRE grade (p&amp;lt;0.0001), advanced pT stage (p&amp;lt;0.0001), presence of nodal and distant metastasis (p&amp;lt;0.0001 each), HER2 overexpression (p=0.005), reduced estrogen and progesterone receptor expression (p&amp;lt;0.0001 each), triple negative status (p&amp;lt;0.0001) and shortened patient survival (p=0.0024). Among 1,149 clear cell renal cell cancers (RCC), low AR immunostaining was linked to high ISUP, Fuhrman and Thoenes grades (p&amp;lt;0.0001 each), high UICC and pT stage (p&amp;lt;0.0001 each), presence of distant metastases (p=0.0075), and reduced time to recurrence (p=0.0007), overall survival (p=0.0097) and tumor-specific survival (p=0.0129). In 297 papillary RCC, low AR staining was associated with high ISUP grade (p=0.0179), advanced pT stage (p=0.0055) and nodal metastasis (p=0.0044). Low AR expression was linked to invasive growth (p&amp;lt;0.0001) and nodal metastasis in urothelial carcinoma (p=0.0052). Conclusion: The results of our study demonstrate AR expression in a wide range of cancers. AR expression occurs most frequent in cancers of the prostate, breast, and ovary, but can be found in many types of non-prostate and non-gynecological neoplasms. The poor prognosis of breast and kidney cancers with reduced AR expression argues against a tumor promoting role of AR in these tumor types. Citation Format: Florian Viehweger, David Dum, Anne Menz, Ria Uhlig, Andrea Hinsch, Doris Höflmayer, Tim Mandelkow, Christoph Fraune, Christian Bernreuther, Patrick Lebok, Sören Weidemann, Guido Sauter, Maximilian Lennartz, Frank Jacobsen, Till S. Clauditz, Till Krech, Andreas H. Marx, Ronald Simon, Stefan Steurer, Eike Burandt, Sarah Minner. Androgen receptor (AR) is frequently found in human cancers and inversely linked to patient outcome in breast and renal cell carcinomas. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5563.

PD38-04 METABOLIC HETEROGENEITY OF HUMAN PROSTATE CANCER BASED ON 18 F-PSMA-1007 AND 18 F-FDG PET/CT AND ITS CLINICOPATHOLOGIC CHARACTERISTICS

You have accessJournal of UrologyCME1 Apr 2023PD38-04 METABOLIC HETEROGENEITY OF HUMAN PROSTATE CANCER BASED ON 18F-PSMA-1007 AND 18F-FDG PET/CT AND ITS CLINICOPATHOLOGIC CHARACTERISTICS Sungun Bang, Hyun Ho Han, Dongwoo Kim, Mijin Yun, and Seung Hwan Lee Sungun BangSungun Bang More articles by this author , Hyun Ho HanHyun Ho Han More articles by this author , Dongwoo KimDongwoo Kim More articles by this author , Mijin YunMijin Yun More articles by this author , and Seung Hwan LeeSeung Hwan Lee More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003336.04AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: 18F-FDG Positron emission tomography/computed tomography (PET/CT) is limited in evaluating prostate cancer (PCa) due to low glycolysis in the primary tumor. Recently, PET/CT targeting the prostate specific membrane antigen (PSMA) has been useful for the diagnosis of biochemical recurrence and subsequent radioligand therapy (RLT). So far, there are limited reports on the value of PSMA PET/CT in detecting primary tumors of the prostate gland. We conducted this study to evaluate the values of 18F-PSMA-1007 and 18F-FDG PET/CT in the primary tumor detection and understand metabolic heterogeneity and related clinicopathologic characteristics at initial presentation. METHODS: This prospective study included 73 tumor regions from 42 patients who underwent both 18F-PSMA-1007 and 18F -FDG PET/CT and subsequent radical prostatectomy. SUVmax of the primary tumors on 18F-PSMA-1007 PET/CT were compared with the histological subtype and Gleason score (GS) by Kruskal-Wallis test with Bonferroni correction and with tumor size, serum PSA, and pathological stage (pStage). GS 6 and 7 were considered low and 8 to 10 were high. pStage I and II were considered early and the rest was advanced. Immunohistochemistry (IHC) was done for glucose transporter, PSMA, and androgen receptor (AR) expression. RESULTS: 18F-PSMA-1007 PET/CT detected all primary tumors with a detection sensitivity of 100% (73/73) whereas 18F-FDG PET/CT detected only 16% (12/73). When tumors were classified into low-GS acinar, high-GS acinar, and high-GS ductal types, SUVmax of 18F-PSMA-1007 uptake was significantly different among the three groups (SUVmax 8.9 in low-GS acinar, 14.7 in high-GS ductal, and 33.9 in high-GS acinar, all p values<0.05). In addition, high 18F-PSMA-1007 uptake was correlated with high serum PSA level, and advanced pStage. There were 12 primary lesions with both 18F-PSMA and 18F-FDG uptake demonstrating a flip-flop phenomenon between the two radiotracer uptake; the foci of increased 18F-FDG uptake showed low 18F-PSMA-1007 uptake and vice versa. All were advanced in pStage with low AR expression on IHC and most of them (9/12) were large ductal tumors. CONCLUSIONS: 18F-PSMA-1007 PET/CT was excellent in detecting primary tumors of all GS in the prostate gland. Some primary tumors showed a reciprocal pattern of 18F-PSMA-1007 and 18F-FDG uptake which were mostly large ductal type with low AR expression. Further studies are needed to see whether tumors with 18F-FDG uptake may predict treatment resistance to androgen deprivation therapy and PSMA RLT. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e994 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sungun Bang More articles by this author Hyun Ho Han More articles by this author Dongwoo Kim More articles by this author Mijin Yun More articles by this author Seung Hwan Lee More articles by this author Expand All Advertisement PDF downloadLoading ...

Abstract C036: Correlation of Kaiso and androgen receptor expression in women of African ancestry with triple-negative breast cancer

Abstract Breast cancer (BCa) is the most frequently diagnosed female cancer and a leading cause of female deaths worldwide, regardless of increased awareness and improved therapies. Triple-negative breast cancer (TNBC) is one of the most challenging BCa subtypes as it is highly heterogeneous, metastatic in nature and has limited targeted therapies. TNBC is most prevalent in young women of African ancestry (WAA), who despite having lower BCa rates, have a disproportionately higher mortality rate compared to women of European ancestry (WEA). However, the cause for this racial disparity is currently unknown, thus highlighting the importance of unraveling the genetic and molecular factors that contribute to TNBC in WAA. Our lab previously showed that the transcription factor Kaiso may be linked to this disparity as it contributes to increased metastasis and mortality in WAA TNBC patients. Interestingly, multiple studies have indicated that WAA TNBC tissues also express less Androgen Receptor (AR) than WEA TNBC tissues, supporting the existence of a novel BCa subtype – quadruple-negative breast cancer (QNBC). Notably, in silico analysis revealed several Kaiso binding sites in the AR promoter region, and that high Kaiso and low AR expression correlated with poorer overall survival in BCa patients. Thus, we hypothesized that high Kaiso and low AR expression could be contributing to the increased mortality in WAA with TNBC. This study seeks to examine the relationship between Kaiso and AR, the clinical significance of this relationship and its role, if any, in TNBC racial disparities. Using tissue microarrays (TMAs) and immunohistochemistry (IHC), we found reduced and cytoplasmic AR expression in WAA compared to WEA. Moreover, preliminary findings from western blot analyses showed an increase in AR expression in response to Kaiso depletion in TNBC cells. These findings suggest that AR could be a bona fide Kaiso target gene and that there may be clinical relevance of high Kaiso, and low AR expression in BCa survival, especially in patients with an African heritage. Ongoing experiments are focused on determining if Kaiso directly associates with the endogenous AR promoter region and discerning the link between high Kaiso and low AR expression in TNBC racial disparities. A significant correlation between Kaiso and AR expression will help to validate the existence of QNBC in WAA and support Kaiso and AR as clinically relevant prognostic markers for TNBC, especially in WAA. Citation Format: Stephanie Ali Fairbairn, Robert Cowan, Juliet M. Daniel, Shawn M. Hercules. Correlation of Kaiso and androgen receptor expression in women of African ancestry with triple-negative breast cancer [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr C036.

H19 in Serum Extracellular Vesicles Reflects Resistance to AR Axis-targeted Therapy Among CRPC Patients.

We aimed to evaluate the changes of androgen receptor (AR) signaling-related long non-coding RNAs (lncRNAs) in serum extracellular vesicles (EVs) from prostate cancer (PC) patients, in order to identify novel biomarkers for AR axis-targeted therapy (ARAT)-resistance among castration-resistant PC (CRPC) patients. EVs were isolated from 2 patients before and after acquiring ARAT-resistance. RNA profiling of EVs was performed by RNA-sequencing. The expression levels of selected lncRNAs in EVs were analyzed by digital droplet PCR (ddPCR) in 58 localized and 14 metastatic PC patients at diagnosis, 7 ARAT-naïve and 6 ARAT-resistant CRPC patients. LncRNA H19 expression in PC tissue was examined using published data. In order to analyze the role of H19, the prognosis was analyzed in PC patients and proteomic analysis was performed in 22Rv1 PC cells. RNA-sequencing revealed that AR-regulated RNAs were most enriched in EVs after acquiring ARAT-resistance. Among them, up-regulation of AR signaling-related lncRNAs (PCAT1, H19, HOXA-11AS, ZEB1-AS1, ARLNC1, PART1, CTBP1-AS and PCA3) was confirmed by ddPCR. H19 contained in EVs (EV-H19) was significantly increased among ARAT-resistant patients compared to ARAT-naïve CRPC or metastatic PC patients. In PC tissue, H19 was negatively correlated with AR protein and AR-activity score and up-regulated in neuroendocrine CRPC tissue with low AR expression. Furthermore, EV-H19 expression was significantly associated with worse outcome to androgen-deprivation therapy. Proteomic analysis demonstrated that H19 knockdown enhanced PC-related protein expression. EV-H19 may negatively correlate with AR-signaling activity and could be a marker to diagnose ARAT-resistance among CRPC patients.

Suppression of androgen receptor signaling induces prostate cancer migration via activation of the CCL20-CCR6 axis.

The suppression of androgen receptor (AR) expression exacerbates the migration potential of prostate cancer. This study identified a previously unrecognized regulation of the AR-controlled pathway that promotes migration potential in prostate cancer cells. Prostate cancer cells that pass through a transwell membrane (mig cells) have a higher migration potential with a decreased AR expression than parental cells. In this study, we aimed to elucidate the mechanism of migration enhancement associated with the suppression of AR signaling. Expression of C-C motif ligand 20 (CCL20) is upregulated in mig cells, unlike in the parental cells. Knockdown of AR with small interfering RNA (siAR) in LNCaP and C4-2B cells increased CCL20 secretion and enhanced the migration of cancer cells. Mig cells, CCL20-treated cells, and siAR cells promoted cell migration with an enhancement of AKT phosphorylation and Snail expression, while the addition of a C-C chemokine receptor 6 (CCR6, the specific receptor of CCL20) inhibitor, anti-CCL20 antibody, and AKT inhibitor suppressed the activation of AKT and Snail. With 59 samples of prostate cancer tissue, CCL20 secretion was profuse in metastatic cases despite low AR expression levels. Snail expression was associated with the expression of CCL20 and CCR6. A xenograft study showed that the anti-CCL20 antibody significantly inhibited Snail expression, thereby suggesting a new therapeutic approach for castration-resistant prostate cancer with the inhibition of the axis between CCL20 and CCR6.

Correlation between Androgen Receptor Expression in Luminal B (HER-2 Negative) Breast Cancer and Disease Outcomes.

(1) Background: Hormone receptor positive breast cancer is a subtype of breast cancer with relatively good prognosis, but luminal B (HER-2 negative) breast cancer has a higher risk of recurrence and metastasis. Patients with endocrine therapy resistance and chemotherapy insensitivity have poor prognosis. Androgen receptor (AR) is widely expressed in breast cancer, but there is no clear conclusion about its function and correlation with prognosis in luminal B breast cancer. Further research is needed to reveal the role of AR in luminal B (HER-2 negative) breast cancer. (2) Methods: Retrospectively analyzed patients with early-stage luminal B breast cancer. The correlation between AR and its associated indexes with long-term survival was determined. (3) Results: A total of 985 patients were included with 143 treated by neoadjuvant therapy. Of these, 83.5% of the patients had AR expression ≥65%. High AR expression was associated with good disease-free survival (DFS) and overall survival (OS). In the neoadjuvant population, AR/estrogen receptor (ER) &gt; 1.06 and residual tumor Ki67 &gt; 23% had significantly worse DFS. (4) Conclusion: Low AR (&lt;65%) expression is associated with poor prognosis in luminal B (HER-2 negative) breast cancer patients. High AR/ER and residual tumor Ki67 were associated with poor DFS in neoadjuvant group with a cutoff value of AR/ER &gt; 1.06 and residual tumor Ki67 &gt; 23%.

Synergistic Prostate Cancer Targeted Radiosensitization by Gold Nanoparticles and Histone Deacetylase Inhibitor Romidepsin

<h3>Purpose/Objective(s)</h3> Histone deacetylase inhibitors (HDACi), such as Romidepsin (FK228) have been confirmed as effective anticancer agents for liquid cancers, but systemic toxicity hinders their application in solid tumors. Gold nanoparticles (GNPs) with tumor specific ligands can be actively accumulated in the targeted tumor, elevating HDACi delivery efficiency. Moreover, GNPs demonstrate their exceptional competence in improving radiosensitization through locally enhanced radiation scatter in the tumor. In this study, we examined the synergistic consequence of prostate cancer treatment with FK228 conjugated GNPs and investigate the molecular mechanism underlying radiosensitization. <h3>Materials/Methods</h3> GNPs were thiolated with N-succinimidyl 3-(2-pyridyldithio)-propionate (SPDP). FK228 and αPSMA antibody were reduced with tris(2-carboxyethyl)-phosphine and mixed with GNPs at a 10:1 ratio, respectively. Dynamic light scattering (DLS) and enzyme linked immunosorbent assay (ELISA) confirmed conjugation, and targeting efficiency was assessed with immunofluorescence (IF) staining of GNPs. PSMA-targeted GNPs (pGNP), and pGNP+FK228 (pfGNP) were treated to LNCaP cells at varying concentrations and monitored on a real time cell analysis (RTCA) system. Western blot (WB) was performed on HDACi pathways. Finally, 2Gy at 160kVp was delivered to cells. 1hr post irradiation, cells were fixed and stained with γH2AX antibodies. Foci count and size were quantified. <h3>Results</h3> DLS showed shift in GNP hydrodynamic size from 49nm to 52nm when conjugated to αPSMA antibody or antibody and FK228. Zeta potential changed from -8mv to -14mV and -20mV in pGNP and pfGNP, respectively. ELISA revealed successful conjugation of αPSMA antibodies with ∼4 antibodies per GNP. IF demonstrated that pfGNP have three-fold higher accumulation on LNCaP cells compared to untargeted GNPs. Based on RTCA, pGNP showed cell killing starting at 1mg/mL at 24hrs, while pfGNP started cell killing at 10µg/mL, but the initiation ranged from 72hrs to 24hrs in a dose dependent manner. At non-toxic concentrations of FK228 and pfGNP, WB revealed both treatments induced a lower expression of androgen receptor and increased expression of ATF3, while pGNP did not. γH2AX assay revealed an increased formation of foci with the treatment of pGNP (158%), FK228 (125%), and pfGNP (170%). There was no statistically significant increase in the foci count between pGNP and pfGNP. However, measurements of total surface area per foci revealed a statistically significant increase in foci size from FK228 and pfGNP compared to pGNP. <h3>Conclusion</h3> FK228 and PSMA-antibodies were successfully conjugated to GNPs using SPDP chemistry. Furthermore, pfGNP demonstrated increased prostate cancer affinity and induced similar cellular signaling as free FK228. Finally, conjugation of FK228 to GNPs synergistically improved prostate cancer radiosensitization through greater induction of double stranded DNA breaks in vitro.

Identification of LAT/ZAP70 characterized immune subtypes of prostate cancer.

While immunotherapy has shown potent efficacy in clinical practices, patient selection to receive checkpoint blockade is still challenging in prostate cancer (PCa). LAT and ZAP70 functions in lymphocyte activation and plays a critical role in T cell receptor (TCR) signal transduction. However, PCa genomic and clinical data regarding the role of LAT and ZAP70 are limited. We aim to identify and characterize LAT/ZAP70 defined subtypes of PCa. We elaborated the TCGA PCa data and metastatic castration-resistant prostate cancer (mCRPC) RNA-seq data bioinformatic analysis and systematically elucidated the role of intra-tumoral expressed LAT and ZAP70 in the progression-free survival and immunotherapeutic-related signals. LAT/ZAP70-associated immune infiltration was evaluated using bioinformatic tools. Immunohistochemical staining of serial sections was used to confirm the expression and distribution of LAT, ZAP70 and androgen receptor (AR) in PCa tissues. Specifically, LAT and ZAP70 revealed increased expressions in PCa when compared to normal tissues and positively associated with intra-tumoral immune cells infiltration. LAT/ZAP70 defined immune-high early-stage PCa revealed higher TP53 mutation frequency and poor prognosis. Transcriptome analysis indicated immune-related signals and CTLA4 expression were highly enhanced in immune-high PCa parallel with higher protein level of MYC and lower AR expression. In mCRPC, LAT/ZAP70 defined immune-high patients also revealed upregulated immune related signals, higher CTLA4 expression and DNA repair deficiency. LAT/ZAP70 defined immune-high PCa linked to immune infiltration and predicts poor prognosis. Immune-high PCa may receive effective response from immune checkpoint inhibitor parallel with systemic treatment.

Androgen receptor regulates eIF5A2 expression and promotes prostate cancer metastasis via EMT

Androgen receptor (AR) is an androgen-activated transcription factor of the nuclear receptor superfamily. AR plays a role in the development and progression of prostate cancer (PCa). However, the exact role of AR in PCa metastasis remains unclear. In the present study, we aimed to elucidate the function of AR in PCa. We found that eukaryotic translation initiation factor (EIF) 5A2, an elongation factor that induces epithelial-to-mesenchymal transition (EMT) in PCa cells, was significantly upregulated after 5α-dihydrotestosterone (DHT) stimulation and downregulated after anti‐androgen bicalutamide treatment in PCa cells with high AR expression, but not in cells with low AR expression. Moreover, eIF5A2 knockdown could eliminate DHT-induced invasion and migration of AR-positive PCa cells. DHT treatment decreased epithelial expression of E‐cadherin and β-catenin but increased the expression of the mesenchymal marker proteins Vimentin and N-cadherin. DHT therefore induced EMT, and knockdown of eIF5A2 inhibited DHT-induced EMT. Moreover, in vivo study, Luciferase signals from the lungs of the eIF5A2 plasmid group indicated higher metastasis ability, and the eIF5A2 siRNA group had lower metastasis ability. Our results suggest that AR positively regulates eIF5A2 expression in androgen-dependent cells, and stimulation of AR expression and signaling in prostate tumors promotes PCa metastasis by EMT induction and upregulation of eIF5A2.

Prostate cancer castrate resistant progression usage of non-canonical androgen receptor signaling and ketone body fuel

Prostate cancer (PCa) that progresses after androgen deprivation therapy (ADT) remains incurable. The underlying mechanisms that account for the ultimate emergence of resistance to ADT, progressing to castrate-resistant prostate cancer (CRPC), include those that reactivate androgen receptor (AR), or those that are entirely independent or cooperate with androgen signaling to underlie PCa progression. The intricacy of metabolic pathways associated with PCa progression spurred us to develop a metabolism-centric analysis to assess the metabolic shift occurring in PCa that progresses with low AR expression. We used PCa patient-derived xenografts (PDXs) to assess the metabolic changes after castration of tumor-bearing mice and subsequently confirmed main findings in human donor tumor that progressed after ADT. We found that relapsed tumors had a significant increase in fatty acids and ketone body (KB) content compared with baseline. We confirmed that critical ketolytic enzymes (ACAT1, OXCT1, BDH1) were dysregulated after castrate-resistant progression. Further, these enzymes are increased in the human donor tissue after progressing to ADT. In an in silico approach, increased ACAT1, OXCT1, BDH1 expression was also observed for a subset of PCa patients that relapsed with low AR and ERG (ETS-related gene) expression. Further, expression of these factors was also associated with decreased time to biochemical relapse and decreased progression-free survival. Our studies reveal the key metabolites fueling castration resistant progression in the context of a partial or complete loss of AR dependence.

Androgen receptor expression and prognosis in Hispanic/Latino women with triple negative breast cancer

Introduction and objectiveTriple-negative breast cancer (TNBC) is an aggressive subtype that has no available molecular targets. It occurs most often in premenopausal African-American and Hispanic/Latino women. In Colombia, its prevalence has been reported to be 20.6%. Androgen receptor (AR) belongs to the steroid nuclear receptor family and has been recently considered a potential biomarker for breast cancer. Considering the high prevalence of TNBC in Colombian women and the lack of knowledge of AR expression, our aim was to determine the frequency of AR expression and its association with pathological variables. Materials and methods149 women diagnosed with TNBC between 2011 and 2014 were included. Clinical and pathological data were obtained from medical and pathology reports. Information on hormone receptor status, Ki67 expression and HER2 was reevaluated by a pathologist. AR expression was considered positive when it exceeded 1% of nuclear staining in tumor cells. ResultsAR expression was detected in 41.6% of the samples. Although we did not find statistically significant differences in clinic-pathological variables according to AR expression, patients with AR expression over 50% were younger (53.92 years vs. 60.78 years, p=0.027) and presented higher Ki67 expression (64.06% vs. 47.32%, p=0.05), compared to patients with a low AR expression. The median overall survival in our sample of TNBC patients was 2.45 years. ConclusionsThe expression of AR in our sample was similar to the expression in populations of European descent. We found statistically significant differences in age at diagnosis and Ki67 expression according to AR expression.

Androgen downregulates desmocollin-2 in association with induction of mesenchymal transition of breast MDA-MB-453 cancer cells.

Desmosomes are cellular structures that are critical in cell-cell adhesion and in maintaining tissue architecture. Changes in the expression of desmocollin-2 (DSC2) have been noted during tumor progression into an invasive phenotype and as cells undergo epithelial-mesenchymal transition. We have previously reported that breast MDA-MB-453 cancer cells, a luminal androgen receptor (AR) model of triple-negative breast cancer, acquire mesenchymal features when treated with the AR agonist, dihydrotestosterone (DHT). We have therefore investigated androgen regulation of the expression and cellular localization of DSC2 in MDA-MB-453 cells. Treatment of the cells with DHT resulted in a dose-dependent reduction in DSC2 protein levels and dispersion of its membrane localization concomitant with AR- and β-catenin-mediated mesenchymal transition of cells. A significant correlation was revealed between decreased expression of AR and increased expression of DSC2 in patient samples. In addition, whereas lower expression of AR was associated with a reduced overall and recurrence-free survival of breast cancer patients, higher expression of DSC2 was found in invasive breast tumors than in normal breast cells and was correlated with lower patient survival. Upon knocking down DSC2, the cells became elongated, mesenchymal-like, and slightly, but insignificantly, more migratory. The addition of DHT further stimulated cell elongation and migration. DSC2 siRNA-transfected cells reverted to a normal epithelial morphology upon inhibition of β-catenin. These results highlight the role of DSC2 in maintaining the epithelial morphology of MDA-MB-453 cells and the negative regulation of the desmosomal protein by DHT during stimulation of the androgen-induced, β-catenin-mediated mesenchymal transition of the cells.

Implications of androgen receptor and FUS expression on tumor progression in urothelial carcinoma.

To examine the immunohistochemical expression of AR and FUS in urothelial carcinoma in relation to prognostic parameters and to extrapolate any possible link between the expression of both markers and tumor progression. Retrospective study using immunohistochemical staining for AR and FUS on (88) cases of urothelial carcinoma. AR shows statistically significant relations with late tumor stage, high tumor grade, and non-papillary tumor pattern. On the other hand, FUS expression correlates with early tumor stage, low tumor grade and papillary pattern. An inverse relation is found between AR and FUS expression (p=0.001). Cases with high AR IHC expression show statistically significant shorter OS, RFS and PFS compared to cases with low AR expression. Cases with high FUS IHC expression reveal statistically significant longer OS, RFS and PFS compared to cases with low FUS expression. FUS expression is associated with favorable prognostic parameters of UC. A possible interaction is suggested between FUS and AR pathways involved in urothelial cancer progression. Manipulating FUS levels and androgen deprivation therapy can provide new promising targets for treatment trials.

Inflammatory infiltration is associated with AR expression and poor prognosis in hormone naïve prostate cancer.

Tumor microenvironment inflammatory infiltration is proposed as a protumorigenic mechanism for prostate cancer with proinflammatory cytokines stimulating androgen receptor (AR) activity. However, association with patient prognosis remains unclear. This study derives an inflammatory gene signature associated with AR expression and investigates CD3+ and CD8+ T-lymphocyte infiltration association with AR and prognosis. Gene profiling of inflammatory related genes was performed on 71 prostate biopsies. Immunohistochemistry on 243 hormone-naïve prostate cancers was performed for CD3, CD8, AR, and phosphorylated AR tumor expression. Multiple proinflammatory genes were differentially expressed in association with high AR expression compared with low AR expression including PI3KCA and MAKP8 (adjusted P < .05). High CD3+ and high CD8+ infiltration associated with reduced cancer-specific survival (P = .018 and P = .020, respectively). High CD3+ infiltration correlated with high tumor cytoplasmic AR expression and if assessed together, they associated with reduced cancer-specific and 5-year survival from 90% to 56% (P = .000179). High CD8+ cytotoxic infiltration associated with high androgen-independent tumor nuclear AR serine 213 phosphorylation (correlation coefficient = 0.227; P = .003) and when assessed together associated with poor clinico-pathological features including perineural invasion (P = .001). Multiple genes involved in proinflammatory signaling pathways are upregulated in high AR expressing prostate samples. T-lymphocyte infiltration in hormone-naïve disease associates with androgen-independent driven disease and provides possible therapeutic targets to reduce transformation from hormone-naïve to castrate-resistant disease.