Androgen Receptor Status Research Articles

Histone deacetylase inhibitor sodium butyrate regulates the activation of toll-like receptor 4/interferon regulatory factor-3 signaling pathways in prostate cancer cells.

The covalent acetylation and deacetylation of histone proteins by the histone deacetylase (HDAC) enzymes can be considered a novel therapeutic target in prostate cancer (PCa) cells. Sodium butyrate (NaBu) is a HDAC inhibitor (HDACi) which is a promising potential anticancer drug. Toll-like receptor 4 (TLR4) expression is increased in PCa cells and HDACi alter TLR-inducible gene expressions. We aimed to evaluate the effects of NaBu on TLR4 mediating signaling pathways in two different PCa cells (DU-145 and LNCaP) for the first time. The cytotoxic and apoptotic effects of NaBu were determined by the water-soluble tetrazolium salt (WST-1) and Annexin V-AO/PI assays, respectively. Subcellular localization of TLR4, interferon regulatory factor-3 (IRF3) and Nuclear factor kappa B proteins was evaluated by IF assay. All data were statistically analyzed by GraphPad Prism software (V60.1, CA). Obtained data were expressed in a mean ± standard deviation of the three repeated experiments. The differences between control and NaBu treated cells were compared by one-way-ANOVA. P < 0.05 value was considered statistically significant. Our results showed that NaBu significantly inhibited the viability of PCa cells and increased the percentage of apoptotic cells. However, DU-145 cells were more sensitive to NaBu than LNCaP cells. Furthermore, NaBu can induce the cytoplasmic TLR4 and IRF3 expression in particularly DU-145 cells without affecting nuclear translocation of NF-kB in PCa cells. NaBu induces apoptotic cell death and regulated the TLR4/IRF3 signaling pathways in DU-145 cells but not in LNCaP cells. Therefore, PCa cells differentially responded to NaBu treatment due to probably androgen receptor status.

Diagnostic Value of Hormonal Receptor Evaluation in Salivary Duct Adenocarcinoma

<h3>Purpose/Objective(s)</h3> Salivary duct carcinomas (SDC) are rare, aggressive, high-grade malignancies that histologically resembles mammary duct cancers. Even given the morphological similarity, as well as the shared embryologic origin of the two tissue types, historically the expression of hormone receptors in salivary duct carcinoma had not been well characterized in the literature, with the majority of immunohistochemical characterization being of Androgen Receptor (AR) and HER2 status. In addition, the role of hormone therapy targeting ER/PR is largely unknown because of the rarity of the tumor. The benefit of chemotherapy remained questionable. With all of this in mind we examined estrogen receptor (ER), progesterone receptor (PR) and HER-2 receptor expressions in salivary duct carcinoma (SDC), with the intent to explore targeted therapeutic options. <h3>Materials/Methods</h3> We reviewed single institution retrospective data of seven patients who were diagnosed with SDC from January 2016 to January 2019. Immunohistochemistry for ER, PR and HER-2 was performed. HER2 was scored as ‘overexpression' if stained 3+. ER/PR were positive if ≥1% of the tumor nuclei were stained at least 1+. The slides were score on the intensity of staining as: negative (0), weakly positive (+1), moderately positive (+2) and strongly positive (+3). <h3>Results</h3> Patients' demographic information, tumor characteristics, and treatment were summarized in the Table 1. Immunohistochemical findings for HER2 status showed one case was positive (3+), three cases were HER2 equivocal (2+), and three cases were HER2 negative (1+). FISH for HER-2 amplification (2–3+) was not performed. PR expression was detectable (1+) in all the seven patients. One of the three patients with metastatic disease was placed on letrozole and maintained disease free progression for 34 months. <h3>Conclusion</h3> Despite the small sample size in our case series, our results indicate salivary duct carcinoma with ER/PR expression. As ER/PR detection is affordable and widely used we recommend routine evaluation of hormonal receptor to explore potential beneficial effects of hormonal receptor blocking agents. Future studies are required to confirm the results as well as to explore the benefit from hormonal blocking agents in SDC.

Abstract OT2-17-01: Randomized, multicenter, international phase 3 ARTEST study to evaluate the efficacy and safety of enobosarm versus active control for the treatment of AR+ ER+ HER2- metastatic breast cancer in patients who progressed on a nonsteroidal aromatase inhibitor, fulvestrant and CDK 4/6 inhibitor

Abstract Targeting the androgen receptor (AR) may be the next important endocrine therapy for women with advanced breast cancer. AR is the most abundantly expressed steroid receptor in breast cancer and has been demonstrated to be a tumor suppressor when activated. Enobosarm is an oral selective nonsteroidal agonist that activates the AR in breast cancer. Enobosarm has an extensive clinical experience in 25 clinical trials and 1,450 dosed subjects including in breast cancer where three Phase 2 studies have been conducted two of which were in women (158 subjects) who had AR+/ER+/HER2- metastatic breast cancer (MBC).The larger Phase 2 clinical trial (G200802) evaluated 9mg and 18mg enobosarm daily oral dosing in 136 women with ER+/HER2- MBC who previously responded to endocrine treatment. Patients were heavily pretreated having progressed on an average of 3 endocrine treatments and 90% had prior chemotherapy. Enobosarm showed efficacy activity in the overall study with a clinical benefit rate at 6 months of 32% (95% CI: 19.5%,46.7%) for the 9 mg and 29% (95% CI: 17.1%,43.1%) for the 18 mg evaluable cohorts. Quality of life assessments showed significant improvement from baseline for both enobosarm cohorts (p=0.002). Enobosarm was well tolerated at both doses. In a post-hoc analysis in all patients (9mg and 18mg) with known AR status and measurable disease (n=84), AR expression in breast. cancer tissue (%AR nuclei staining) correlated with efficacy outcomes. When comparing AR nuclei staining ≥40% (n=47) compared to patients with an AR nuclei staining &amp;lt;40% (n=37): 1) Clinical benefit rate at 6 months was 52% for AR ≥40% and 14% for AR &amp;lt;40% (p&amp;lt;0.0004); 2) Overall response rate (ORR) was 34% for AR ≥40% and 2.7% for AR &amp;lt;40% (p&amp;lt;0.0003; 3) Radiographic was 5.47 months for AR ≥40% and 2.72 months for AR &amp;lt;40% (p&amp;lt;0.001). The ARTEST trial is a Phase 3 multicenter, international randomized, open-label, two treatment arm, efficacy and safety study. Approximately, 210 subjects with AR+ ER+ HER2- MBC and with AR nuclei staining ≥40% will be randomized 1:1 to either enobosarm 9mg oral daily dose or an active comparator (either exemestane ± everolimus or selective estrogen receptor modulator; physician’s choice). Subjects will be treated until disease progression is observed or an unacceptable adverse event is observed. The primary endpoint of the study is imaging based progression free survival as measured by RECIST 1.1. The secondary objectives/endpoints on this study include the ORR, duration of response, overall survival, and change from baseline in Short Physical Performance Battery (SPPB). The study is planned to begin enrollment in Q3 2021. Citation Format: Adam Brufsky, Hannah Linden, Hope Rugo, Charles Vogel, Joyce A O'Shaughnessy, Robert H Getzenberg, K. Gary Barnette, Domingo Rodriguez, Mitchell S Steiner, Erica Mayer. Randomized, multicenter, international phase 3 ARTEST study to evaluate the efficacy and safety of enobosarm versus active control for the treatment of AR+ ER+ HER2- metastatic breast cancer in patients who progressed on a nonsteroidal aromatase inhibitor, fulvestrant and CDK 4/6 inhibitor [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr OT2-17-01.

New Insights and Emerging Therapeutic Approaches in Prostate Cancer.

Prostate cancer is the second most frequently diagnosed cancer in men and several therapeutic approaches are currently available for patient’s care. Although the androgen receptor status represents a good predictor of response to androgen deprivation therapy, prostate cancer frequently becomes resistant to this approach and spreads. The molecular mechanisms that contribute to progression and drug-resistance of this cancer remain still debated. However, few therapeutic options are available for patient’s management, at this stage. Recent years have seen a great expansion of the studies concerning the role of stromal-epithelial interactions and tumor microenvironment in prostate cancer progression. The findings so far collected have provided new insights into diagnostic and clinical management of prostate cancer patients. Further, new fascinating aspects concerning the intersection of the androgen receptor with survival factors as well as calcium channels have been reported in cultured prostate cancer cells and mouse models. The results of these researches have opened the way for a better understanding of the basic mechanisms involved in prostate cancer invasion and drug-resistance. They have also significantly expanded the list of new biomarkers and druggable targets in prostate cancer. The primary aim of this manuscript is to provide an update of these issues, together with their translational aspects. Exploiting the power of novel promising therapeutics would increase the success rate in the diagnostic path and clinical management of patients with advanced disease.

Overactivation of the androgen receptor exacerbates gravid uterine ferroptosis via interaction with and suppression of the NRF2 defense signaling pathway.

The mechanisms through which the androgen-dependent activation of the androgen receptor (AR) regulates gravid uterine ferroptosis remain unknown. We show that while co-exposure of pregnant rats to the androgen 5α-dihydrotestosterone (DHT) and insulin (INS) triggered uterine ferroptotic signaling cascades, additional treatment with the anti-androgen flutamide increased expression of the key ferroptosis-inhibitory proteins SLC7A11, GSH, and GPX4; reduced iron content; normalized levels of ferroptosis-associated Tfrc, Fpn1, and Ho1 mRNAs; reduced levels of proteins modified by 4-HNE (a marker of ferroptosis); and restored protein levels of NRF2, a key transcription factor regulating antioxidant defense signaling, in the gravid uterus. Furthermore, exposure to DHT alone increased uterine ferroptosis, and NRF2 abundance was negatively correlated with AR status. Co-immunoprecipitation and Western blot assays revealed that the AR physically interacted with endogenous NRF2, and this interaction was increased by DHT exposure in vivo. Our results suggest that AR overactivation and NRF2 suppression cooperate in the regulation of NRF2-targets in uterine ferroptosis.

Sex Hormone-regulatedCMG2Is Involved in Breast and Prostate Cancer Progression

Capillary morphogenesis gene 2 (CMG2) is involved in prostate and breast cancer progression. This study aimed to investigate sex hormone receptor-mediated regulation of CMG2 in breast and prostate cancer, and its implication in disease progression. Expression of CMG2, oestrogen receptor (ER) and androgen receptor (AR) was determined in breast and prostate cancer cell lines, respectively, using real-time quantitative PCR (QPCR) and western blot. Association between CMG2 and sex hormone receptors was analysed in a number of transcriptome datasets. Immunochemical staining was performed in tissue microarrays of breast cancer (BR1505D) and prostate cancer (PR8011A). CMG2 expression was determined in 17β-oestradiol treated breast cancer cells and AR over-expressing prostate cancer cells. CMG2 was found to be inversely correlated with sex hormone receptors in breast and prostate cancer. Lower expression of CMG2 was associated with a poor prognosis in ER (+) breast cancer but not ER (-) tumours. Both ER (+) breast cancer cell lines and AR (+) prostate cancer cell lines presented lower expression of CMG2, which was increased following sex hormone deprivation. Exposure to 17-β-oestradiol and AR over-expression repressed CMG2 expression in breast cancer and prostate cancer cell lines, respectively. CMG2 is inversely correlated with ER and AR status in breast and prostate cancer, respectively. ER and AR mediate repression of CMG2 expression in corresponding cancerous cells.

Reprogramming landscape highlighted by dynamic transcriptomes in therapy-induced neuroendocrine differentiation

Metastatic and locally advanced prostate cancer is treated by pharmacological targeting of androgen synthesis and androgen response via androgen signaling inhibitors (ASI), most of which target the androgen receptor (AR). However, ASI therapy invariably fails after 1–2 years. Emerging clinical evidence indicates that in response to ASI therapy, the AR-positive prostatic adenocarcinoma can transdifferentiate into AR-negative neuroendocrine prostate cancer (NEPC) in 17–25 % treated patients, likely through a process called neuroendocrine differentiation (NED). Despite high clinical incidence, the epigenetic pathways underlying NED and ASI therapy-induced NED remain unclear. By utilizing a combinatorial single cell and bulk mRNA sequencing workflow, we demonstrate in a time-resolved manner that following AR inhibition with enzalutamide, prostate cancer cells exhibit immediate loss of canonical AR signaling activity and simultaneous morphological change from epithelial to NE-like (NEL) morphology, followed by activation of specific neuroendocrine (NE)-associated transcriptional programs. Additionally, we observed that activation of NE-associated pathways occurs prior to complete repression of epithelial or canonical AR pathways, a phenomenon also observed clinically via heterogenous AR status in clinical samples. Our model indicates that, mechanistically, ASI therapy induces NED with initial morphological change followed by deactivation of canonical AR target genes and subsequent de-repression of NE-associated target genes, while retaining AR expression and transcriptional shift towards non-canonical AR activity. Coupled with scRNA-seq and CUT&RUN analysis, our model system can provide a platform for screening of potential therapeutic agents that may prevent ASI-induced NED or reverse the NED process.

Androgen receptor expression in patients with triple negative breast cancer treated with neoadjuvant chemotherapy: a single institution study.

Background: Androgen receptor (AR) expression has emerged as a potential prognostic and predictive marker in patients with triple negative breast cancer (TNBC). We conducted a retrospective analysis to evaluate pathologic complete response (pCR) rates, disease-free survival (DFS) and overall survival (OS) in patients with AR positive and AR negative TNBC treated with neoadjuvant chemotherapy.Methods: 107 patients with TNBC subtype, treated with neoadjuvant chemotherapy between June 2006 and March 2016 were evaluated for AR expression. Androgen receptors were evaluated by immunohistochemical staining (clone AR441, Dilution 1:50, Dako-Agilent, Santa Clara, CA) using whole tissue sections from archived paraffin-embedded formalin-fixed (FFPE) blocks. AR positive was defined as ≥10% nuclear stained cells. Correlation of AR expression was examined with age, BMI, race, menopausal status, tumor grade, tumor size, and lymph node involvement, and response and outcomes. Univariate and multivariate analyses were performed to determine an association with AR expression and pathologic response and survival outcomes.Results: Fifty-eight patients with available tumor specimens were stained, with twenty (34.5%) being AR-positive and thirty-eight (65.5%) being AR negative. Median age was 49 years and median follow up was 5.7 years. All patients received anthracycline based neoadjuvant chemotherapy with 13 patients (23%) receiving an additional platinum chemotherapy. BRCA mutation positivity was 7% for the entire group. No differences in age, menopausal status, BMI, race, tumor size and lymph node involvement were observed between the two groups. However, there was a statistically significant difference in tumor grade between the two groups (p=0.008). Overall pCR rate was 28% with no difference between the two groups (30% vs 26%, p=0.56). There was no statistically significant difference in median DFS (5.9 years vs 5.2 years (p=0.94) and median OS (6.2 years vs 5.4 years, p=0.98) between the AR positive and AR negative groups.Conclusions: Our study did not find an association of AR status and the pathologic responses or survival outcomes in patients with TNBC treated with neoadjuvant chemotherapy. Further studies exploring the prognostic and predictive role of AR in patients with TNBC are warranted.

Development and validation of a nomogram based on pretreatment dynamic contrast-enhanced MRI for the prediction of pathologic response after neoadjuvant chemotherapy for triple-negative breast cancer.

To develop a nomogram based on pretreatment dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to predict pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) in patients with triple-negative breast cancer (TNBC). A total of 108 female patients with TNBC treated with neoadjuvant chemotherapy followed by surgery between January 2017 and October 2020 were enrolled. The patients were randomly divided into the primary cohort (n = 87) and validation cohort (n = 21) at a ratio of 4:1. The pretreatment DCE-MRI and clinicopathological features were reviewed and recorded. Univariate analysis and multivariate logistic regression analyses were used to determine the independent predictors of pCR in the primary cohort. A nomogram was developed based on the predictors, and the predictive performance of the nomogram was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC). The validation cohort was used to test the predictive model. Tumor volume measured on DCE-MRI, time to peak (TTP), and androgen receptor (AR) status were identified as independent predictors of pCR. The AUCs of the nomogram were 0.84 (95% CI: 0.75-0.93) and 0.79 (95% CI: 0.59-0.99) in the primary cohort and validation cohort, respectively. Pretreatment DCE-MRI could predict pCR after NAC in patients with TNBC. The nomogram can be used to predict the probability of pCR and may help individualize treatment. • Pretreatment DCE-MRI findings can predict pathologic complete response (pCR) after neoadjuvant chemotherapy in patients with triple-negative breast cancer. • A nomogram based on the independent predictors of tumor volume measured on DCE-MRI, time to peak, and androgen receptor status could help personalized cancer treatment in TNBC patients.

A biomarker study in Peruvian males with breast cancer.

BACKGROUNDBreast cancer (BC) frequency in males is extremely low and tumor features vary from its female counterpart. Breast cancer clinical and pathological features differ by race in women. Tumor infiltrating lymphocyte (TIL) levels, mismatch repair (MMR) protein loss, androgen receptor (AR) expression, and PIK3CA gene mutations are predictive biomarkers of response to biological therapy in female BC. There is limited information about clinical and pathological features as well as predictive biomarkers in males of non-Caucasian races with BC. AIMTo investigate clinicopathological features and biomarkers of BC tumors in males and their prognostic value in Peruvian population. METHODSThis study looked at a single-institution series of 54 Peruvian males with invasive BC who were diagnosed from Jan 2004 to June 2018. Standard pathological features, TIL levels, MMR proteins, AR immunohistochemistry staining, and PIK3CA gene mutations were prospectively evaluated in cases with available paraffin material. Percentage of AR and estrogen receptor (ER) positive cells was additionally calculated by software after slide scanning. Statistical analyses included association tests, intraclass correlation test and Kaplan Meier overall survival curves.RESULTSThe median age was 63 years and most cases were ER-positive (85.7%), HER2 negative (87.2%), Luminal-A phenotype (60%) and clinical stage II (41.5%) among our male breast tumors. Median TIL was 10% and higher levels tended to be associated with Luminal-B phenotype and higher grade. AR-positive was found in 85.3% and was correlated with ER (intraclass index of 0.835, P < 0.001). Loss of MMR proteins was found in 15.4% and PIK3CA mutation (H1047R) in 14.3% (belonged to the Luminal-A phenotype). Loss of MMR proteins was associated with AR-negative (P = 0.018) but not with ER (P = 0.43) or TIL (P = 0.84). Early stages (P < 0.001) and lower grade (P = 0.006) were associated with longer overall survival. ER status, phenotype, AR status, TIL level, MMR protein loss nor PIK3CA mutation was not associated with survival (P > 0.05).CONCLUSIONMale BC is usually ER and AR positive, and Luminal-A. MMR loss and PIK3CA mutations are infrequent. Stage and grade predicted overall survival in our South American country population.

Multi-Parametric MRI-Based Radiomics Models for Predicting Molecular Subtype and Androgen Receptor Expression in Breast Cancer.

ObjectiveTo investigate whether radiomics features extracted from multi-parametric MRI combining machine learning approach can predict molecular subtype and androgen receptor (AR) expression of breast cancer in a non-invasive way.Materials and MethodsPatients diagnosed with clinical T2–4 stage breast cancer from March 2016 to July 2020 were retrospectively enrolled. The molecular subtypes and AR expression in pre-treatment biopsy specimens were assessed. A total of 4,198 radiomics features were extracted from the pre-biopsy multi-parametric MRI (including dynamic contrast-enhancement T1-weighted images, fat-suppressed T2-weighted images, and apparent diffusion coefficient map) of each patient. We applied several feature selection strategies including the least absolute shrinkage and selection operator (LASSO), and recursive feature elimination (RFE), the maximum relevance minimum redundancy (mRMR), Boruta and Pearson correlation analysis, to select the most optimal features. We then built 120 diagnostic models using distinct classification algorithms and feature sets divided by MRI sequences and selection strategies to predict molecular subtype and AR expression of breast cancer in the testing dataset of leave-one-out cross-validation (LOOCV). The performances of binary classification models were assessed via the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). And the performances of multiclass classification models were assessed via AUC, overall accuracy, precision, recall rate, and F1-score.ResultsA total of 162 patients (mean age, 46.91 ± 10.08 years) were enrolled in this study; 30 were low-AR expression and 132 were high-AR expression. HR+/HER2− cancers were diagnosed in 56 cases (34.6%), HER2+ cancers in 81 cases (50.0%), and TNBC in 25 patients (15.4%). There was no significant difference in clinicopathologic characteristics between low-AR and high-AR groups (P > 0.05), except the menopausal status, ER, PR, HER2, and Ki-67 index (P = 0.043, <0.001, <0.001, 0.015, and 0.006, respectively). No significant difference in clinicopathologic characteristics was observed among three molecular subtypes except the AR status and Ki-67 (P = <0.001 and 0.012, respectively). The Multilayer Perceptron (MLP) showed the best performance in discriminating AR expression, with an AUC of 0.907 and an accuracy of 85.8% in the testing dataset. The highest performances were obtained for discriminating TNBC vs. non-TNBC (AUC: 0.965, accuracy: 92.6%), HER2+ vs. HER2− (AUC: 0.840, accuracy: 79.0%), and HR+/HER2− vs. others (AUC: 0.860, accuracy: 82.1%) using MLP as well. The micro-AUC of MLP multiclass classification model was 0.896, and the overall accuracy was 0.735.ConclusionsMulti-parametric MRI-based radiomics combining with machine learning approaches provide a promising method to predict the molecular subtype and AR expression of breast cancer non-invasively.

Abstract 2070: Androgen deprivation and its impact on DNA repair in combination with ionising radiation and Radium-223 in prostate cancer

Abstract Abiraterone acetate and Enzalutamide are novel anti-androgens shown to be one of the few treatments to improve both progression-free survival and overall survival in patients with metastatic castration-resistant prostate cancer. However, many questions exist regarding the optimal combination and scheduling with radiation, the degree of additivity or synergism and the underlying mechanisms governing any potential synergy. This study is attesting the biological rationale for the selection of Abiraterone or Enzalutamide as, currently, the choice of therapy is a clinical decision based on experience and side effect profiles. As well as external beam radiotherapy a key unexplored area of interest is the combination of these inhibitors with the α-emitter radium-223, which targets bone metastases, with preliminary studies, such as the ERA-223 study, highlighting the need for further studies to mechanistically determine if these combinations are effective and safe. To better understand this, we conducted a detailed analysis of the effects of Abiraterone (10µM), Enzalutamide (10µM) or DMSO (Control) alone or in combination with a dose range of X-rays and radium-223 exposure on cell cycle, DNA damage, DNA repair and cell viability across a panel of androgen-insensitive (PC3), androgen-sensitive (LNCaP) and osteoblastic bone models (SJSA-1, SAOS-2). We report significant differences in the synergy of these AR inhibitors in combination with radiation, with Abiraterone causing significant radiosensitisation regardless of AR status and radiosensitisation with Enzalutamide being dependent on AR-sensitivity. This suggests a potential alternative mechanism of action of Abiraterone, not dependent on AR status. AR suppression alone was also shown to impact cell-cycle distribution, with most notable changes being increases in sub-G1 at the expense of S phase, with observed increases in PARP-cleavage supporting this being a result of increased levels of apoptosis and potential reductions in RAD51 levels. Studies with radium-223 confirmed the highly damaging nature of α-particles, with radium-223 treatments shown to be highly cytotoxic compared to equivalent doses of X-rays. Compared to X-rays, radium-223 induced cell cycle distribution changes in the form of much larger shifts towards G2, which also took longer to recover. As well as increased levels of apoptosis through observed increases in PARP-cleavage. Combinations of radium-223 with Abiraterone or Enzalutamide led to a loss of all additive or synergistic effects previously measured with X-rays. Most likely due to the highly cytotoxic nature of α-particles due to the induction of non-reparable DNA dsb. In conclusion, these results support the use of Abiraterone and Enzalutamide in combination with X-rays and radium-223 to enhance tumor response independently of androgen receptor status. Citation Format: Timothy Wright, Victoria Dunne, Aidan Cole, Kevin Prise. Androgen deprivation and its impact on DNA repair in combination with ionising radiation and Radium-223 in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2070.

Biological and clinical features of triple negative Invasive Lobular Carcinomas of the breast. Clinical outcome and actionable molecular alterations

BackgroundWe report here for the first time, a comprehensive characterization of biological and clinical features of early-stage triple negative Invasive Lobular Carcinomas(TN-ILCs) MethodsWe analyzed all consecutive patients with early-stage TN-ILC operated at two reference cancer-centers between 1994 and 2012.Primary objective was to assess the invasive disease-free survival(iDFS).Co-primary objective was to assess biological features of TN-ILCs, including molecular intrinsic subtypes based on PAM-50 assay, expression of androgen receptor (AR) and mutational status of ERBB2-gene.Additionally, DNA mutational status of an independent cohort of 45 TN-ILCs from three databases were analyzed, to confirm mutations in ERBB2-gene and to identify other recurrently mutated genes. ResultsAmong 4152 ILCs, 74(1.8%) were TN and were analyzed.The iDFS at 5 and 10 years of FUP were 50.4%(95%CI,38.0–61.6) and 37.2%(95%CI,25.5–48.8), respectively.The molecular subtype was defined through PAM50-classifier for 31 out of 74 TN-ILCs: 48% were Luminal-A(15/31), 3% luminal-B(1/31), 32% HER2-enriched (10/31), and only 16% basal-like(5/31).Luminal tumors expressed AR more frequently than non-luminal tumors (AR≥1% in 94% of luminal tumors versus 53% in non-luminal tumors; p-value = 0.001).20% of TN-ILCs analyzed(7/35), harbored a pathogenetic and actionable mutation in the ERBB2-gene. Analysis of the independent cohort of 45 TN-ILCs from three different databases, confirmed similar percentage of pathogenetic and actionable mutations in ERBB2-gene(20%; 9/45).Among the top 10 molecular pathways significantly enriched for recurrently mutated genes in TN-ILCs(FDR<0.05), there were ErbB-signaling and DNA-damage-response pathways. ConclusionsTN-ILCs are rare tumors with poor prognosis. Their specific biological features require newly defined targeted therapeutic strategies

Immune checkpoint B7-H3 protein expression is associated with poor outcome and androgen receptor status in prostate cancer.

Novel immune checkpoint-based immunotherapies may benefit specific groups of prostate cancer patients who are resistant to other treatments. We analyzed by immunohistochemistry the expression of B7-H3, PD-L1/B7-H1, and androgen receptor (AR) in tissue samples from 120 prostate adenocarcinoma patients treated with radical prostatectomy in Spain, and from 206 prostate adenocarcinoma patients treated with radical prostatectomy in Norway. B7-H3 expression correlated positively with AR expression and was associated with biochemical recurrence in the Spanish cohort, but PD-L1 expression correlated with neither of them. Findings for B7-H3 were validated in the Norwegian cohort, where B7-H3 expression correlated positively with Gleason grade, surgical margins, seminal vesicle invasion, and CAPRA-S risk group, and was associated with clinical recurrence. High B7-H3 expression in the Norwegian cohort was also consistent with positive AR expression. These results suggest distinct clinical relevance of the two immune checkpoint proteins PD-L1 and B7-H3 in prostate cancer. Our findings highlight B7-H3 as an actionable novel immune checkpoint protein in prostate cancer.

Imaging Androgen Receptors in Breast Cancer with 18F-Fluoro-5α-Dihydrotestosterone PET: A Pilot Study.

Most breast cancers express androgen receptors (ARs). This prospective imaging substudy explored imaging of ARs with 18F-fluoro-5α-dihydrotestosterone (18F-FDHT) PET in patients with metastatic breast cancer (MBC) receiving selective AR modulation (SARM) therapy (GTx-024). Methods: Eleven postmenopausal women with estrogen receptor-positive MBC underwent 18F-FDHT PET/CT at baseline and at 6 and 12 wk after starting SARM therapy. Abnormal tumor 18F-FDHT uptake was quantified using SUVmax AR status was determined from tumor biopsy specimens. 18F-FDHT SUVmax percentage change between scans was calculated. Best overall response was categorized as clinical benefit (nonprogressive disease) or progressive disease using RECIST 1.1. Results: The median baseline 18F-FDHT SUVmax was 4.1 (range, 1.4-5.9) for AR-positive tumors versus 2.3 (range, 1.5-3.2) for AR-negative tumors (P = 0.22). Quantitative AR expression and baseline 18F-FDHT uptake were weakly correlated (Pearson ρ = 0.39, P = 0.30). Seven participants with clinical benefit at 12 wk tended to have larger declines in 18F-FDHT uptake than did those with progressive disease both at 6 wk after starting GTx-024 (median, -26.8% [range, -42.9% to -14.1%], vs. -3.7% [range,-31% to +29%], respectively; P = 0.11) and at 12 wk after starting GTx-024 (median, -35.7% [range, -69.5% to -7.7%], vs. -20.1% [range, -26.6% to +56.5%], respectively; P = 0.17). Conclusion: These hypothesis-generating data suggest that 18F-FDHT PET/CT is worth further study as an imaging biomarker for evaluating the response of MBC to SARM therapy and reiterate the feasibility of including molecular imaging in multidisciplinary therapeutic trials.

Androgen Activity in the Primary and Metastatic Prostate Cancer Microenvironments Influences Disease Progression and Patient Outcomes

Abstract Background: Cancers do not exist in isolation, surrounding tumours are supportive cells, which create the microenvironment in which cancer cells reside. In the prostate cancer (PCa), androgen receptor (AR) signalling in the surrounding fibroblasts is strikingly distinct from that within PCa cells, and has specific functions to produce, maintain, and modulate the extracellular matrix (ECM) which surrounds and interacts with PCa cells. The supportive cells of metastatic sites differ from those in the primary site and produce different types of cellular microenvironments. Since the advent of second generation anti-androgen therapy there has been an increase in the presence of liver metastasis. This project investigates how AR and anti-androgen therapy affect the prostate liver microenvironment and the subsequent effects on cancer. Results: Analysis of microenvironment of primary and metastatic sites indicates transcriptional responses distinct from that seen in PCa cells. This is exemplified by proliferation responses to androgen and anti-androgens in microenvironment cells being the reverse to that seen in Pca cells. Dichotomising microdissected PCa patient material of matched cancer and stromal tissue, based on stromal AR level shows distinct transcriptional profiles in the matched cancer cells. From previous studies, we know AR status in cancer adjacent fibroblasts (CAFs) of the primary tumor inversely associates with patient outcomes. Analysis of single cell CAFs and microdissected stromal samples points to a potential sub population of CAFs with this AR status. Conditioned media from liver and prostate fibroblast cells suggests that inactivation of AR signalling produces proliferative paracrine signals that can affect cancer cell growth. AR in primary site fibroblast and liver stellate cells regulates secretome and ECM production in the primary and metastatic site. Prostates and livers from enzalutamide treated mice showed changes in collagen fibres compared to control mice, as visualised by picro-direct-red staining. We cultured PCa cells within 3D-ECM microenvironments created in vitro from prostate fibroblasts or liver cells. The different 3D-ECM were able to produce changes in PCa cells, including gene transcription, intracellular signalling pathways, and proliferation and apoptotic responses. These data suggest that the responses of primary and metastatic microenvironments to androgens and anti-androgens can influence phosphorylation of intracellular pathways leading to alterations in gene transcription. Furthermore, the transcriptional responses of cancer cells in vitro to changes in microenvironmental AR signalling can be used to predict patient outcomes. Conclusions: Our data suggests that anti-AR therapy produces organ microenvironment-specific signals that influence the response of prostate cancer to treatments and affects patient outcomes.

Expression of G3BP1 in benign and malignant human prostate tissues.

BackgroundProstate cancer (PCa) is the world’s leading type of cancer in men. GTPase-activating protein SH3 domain-binding protein 1 (G3BP1) is overexpressed in a variety of tumors. However, there are limited studies in PCa concerning G3BP1. This present study was to investigates the expression of G3BP1 and the mechanism of action on PCa.MethodsWe explored the G3BP1 expression in PCa using the TCGA database and verified it using clinical samples by immunohistochemistry (IHC) methods. G3BP1 and Androgen receptor (AR) status of 104 human PCa and 50 benign prostate hyperplasia (BPH) samples were analyzed by IHC and the association between G3BP1 expression and biochemical recurrence was determined. Moreover, we generated G3BP1 knockdown cell lines in human PCa LNCaP cell lines, to observe AR changes.ResultsG3BP1 and AR were overexpressed in PCa compared to BPH tissues. The expression of G3BP1 and AR was positively correlated with the malignant degree of the tumor. Higher G3BP1 expression showed a trend toward biochemical recurrence. Western blot showed downregulation of G3BP1 affected AR expression levels.ConclusionsOur study suggested that G3BP1 was frequently upregulated in PCa and closely related to AR expression and tumor metastasis. Besides, G3BP1 might be associated with biochemical recurrence. These results supply potential target for the management of the PCa.

Implications for management of ovarian cancer in a transgender man: Impact of androgens and androgen receptor status

A 36-year-old transgender man (assigned female at birth) on exogenous testosterone therapy was found to have stage IIA ovarian endometrioid carcinoma, and underwent adjuvant chemotherapy. Diffuse androgen receptor expression in the tumor initiated a multidisciplinary discussion regarding the safety of continuing exogenous testosterone as gender-affirming hormone therapy.

Differential CircRNA Expression Signatures May Serve as Potential Novel Biomarkers in Prostate Cancer.

Circular RNAs (circRNAs), a recently discovered non-coding RNA, have a number of functions including the regulation of miRNA expression. They have been detected in a number of malignancies including prostate cancer (PCa). The differential expression pattern of circRNAs associated with PCa and androgen receptor (AR) status was investigated in this study. circRNA profiling was performed using a high throughout microarray assay on a panel of prostate cell lines, which consisted of normal, benign, and malignant cells (n = 9). circRNAs were more commonly significantly up-regulated (p < 0.05) than downregulated in malignant cell lines (n = 3,409) vs. benign cell lines (n = 2,949). In a grouped analysis based on AR status, there were 2,127 down-regulated circRNAs in androgen independent cell lines compared to 2,236 in androgen dependent cell lines, thus identifying a potential circRNA signature reflective of androgen dependency. Through a bioinformatics approach, the parental genes associated with the top 10 differentially expressed circRNAs were identified such as hsa_circ_0064644, whose predicted parental gene target is RBMS3, and hsa_circ_0060539, whose predicted gene target is SDC4. Furthermore, we identified three circRNAs associated with the parental gene Caprin1 (hsa_circ_0021652, hsa_circ_0000288, and hsa_circ_0021647). Other studies have shown the importance of Caprin1 in PCa cell survival and drug resistance. Given the modified circRNA expression signatures identified here, these hypothesis generating results suggest that circRNAs may serve as potential putative diagnostic and predictive markers in PCa. However, further validation studies are required to assess the true potential of these markers in the clinical setting.

English

BACKGROUND Understanding various risk factors associated with breast cancer can help in early identification &amp; prompt treatment of patients with breast cancer. Apart from clinical parameters like age, disease presentation and menopausal status, important prognostic indicators in histopathology are size and extent of tumour, histologic type,histologic grade and lymph node status. Also, there are other factors which are not only predictive of outcome, but also direct therapies against particular molecular targets. These factors are oestrogen receptor (ER) status, progesterone receptor (PR) status, HER2 / neu status, Ki-67 proliferation index &amp; androgen receptor (AR) status. We wanted to analyse various hormone receptors &amp; their correlation with prognostic factors. In addition, androgen receptor expression is also studied in triple negative breast cancer cases. METHODS The study included 50 cases over a period of 18 months from January 2018 to June 2019 received in the Department of Pathology, Gandhi Medical College, Bhopal, India. These cases were subjected to histopathological &amp; immunohistochemistry (IHC) evaluation. RESULTS Among the 50 cases studied, the most common subtype was infiltrating ductal carcinoma (NOS - no special type, 84 %). Majority of patients were ER, PR, HER2 / neu negative (48 %) and among those triple negative cases, 25 % of cases were androgen receptor positive. CONCLUSIONS Expression of the hormone receptor (ER and PR) and HER2 status may provide significant information in directing patient management. Since traditional pathological methods and IHC remain standard for guiding the use of treatment, clinicians may be challenged with equivocal results that directs towards additional testing for definitive diagnosis and, better patient outcome. The most used therapy for advanced breast cancers is based on the use of AR antagonists, such as bicalutamide and enzalutamide, first- and second-generation AR antagonists respectively. Gene signatures, bioinformatics, and other clinical trials are also beneficial for clinician in estimating the benefits expected from adjuvant chemotherapy. KEY WORDS Breast Cancer, Oestrogen Receptor, Androgen Receptor, Triple Negative