Androgen Receptor Research Articles

Embryonal exposure to 4-methylbenzylidene camphor induces reproduction impairment in adult zebrafish (Danio rerio)

This study investigated how early exposure to xenobiotics can lead to disease in adulthood, which is challenging for toxicologists. We employed a ‘cradle to grave’ approach using zebrafish (Danio rerio) embryos exposed to 4-methylbenzylidene camphor (4-MBC), a commonly used organic UV filter. Molecular docking and simulation studies confirmed the predictive toxicity and stable interaction of 4-MBC with androgen and estrogen receptors, with binding energies of −9.28 and −9.01 kcal/mol, respectively. Exposure to 4-MBC at 5, 50, and 500 μg/L concentrations resulted in significantly altered transcriptional and translational responses of ar, esr1, and vtg1 genes in embryos at 120 h post-fertilization (hpf). The exposure induced a non-monotonic dose-response pattern (NMDR), a characteristic feature of endocrine-disrupting chemicals. Additionally, a significant decrease in fertilization was observed in adults. Although fecundity was not affected in inter- and intra-breeding performances, developmental deformities were observed in F1 progenies with impaired survival at 10 days post-fertilization. The findings of this study show that embryonic exposure to 4-MBC is likely to induce reproductive and transgenerational toxicity in D. rerio and exhibit endocrine disruption in aquatic non-target organisms. This work is the first to elucidate the low-level long-term effects of 4-MBC from the embryonic stage to adulthood.

Examination of the anabolic activity and mechanisms of action of the combination of Diosgenin and Ecdysterone in C2C12 myotubes

Plant steroids such as ecdysterone (ECDY) or diosgenin (DIO) have been associated with anabolic and performance-enhancing effects for years. However, the molecular mechanisms have not yet been extensively studied in skeletal muscle cells. Consequently, the anabolic activity and associated molecular mechanisms of ECDY and DIO alone and in combination were investigated in C2C12 myotubes. Dose-dependent effects of both compounds on myotube diameter, mRNA expression of IGF-1 and PI3KR1 as well as expression of myosin heavy chain (MHC) proteins were analyzed in differentiated C2C12 cells. In addition, the binding affinities to androgen and estrogen receptors were analyzed. Treatment with ECDY and DIO significantly induced hypertrophy of C2C12 myotubes. Partially additive effects were observed. This is supported by the mRNA expression of IGF-1 and PI3KR1 as well as in the expression of MHC. However, no clear statement can be made regarding which combination has the strongest additive effects. Besides the results suggest that, in contrast to ECDY, DIO has antiandrogenic effects and bind on AR. Consequently, it indicate that two different mechanisms of action are activated in ECDY and DIO combinations. However, this must be confirmed in further cell cultures studies and human interventions concerning anti-doping regulations.

131 (PB119): Novel Androgen Receptor Antagonists with Improved Activity Against Common LBD Variants Associated with Therapeutic Resistance

131 (PB119): Novel Androgen Receptor Antagonists with Improved Activity Against Common LBD Variants Associated with Therapeutic Resistance

Clinico-Pathological Factors and AR-LBD Mutations in Early and Late Castration-Resistant Prostate Cancer.

Prostate cancer (PCa) is not well understood because of its enormous biological heterogeneity and unreliable progression. We conducted this retrospective analysis to examine the variables predicting early and late progression to castration-resistant PCa (CRPC) for better management of this disease. This single institutional retrospective study was conducted from January 2018 to January 2022. A total of 98 consecutive men meeting with the diagnosis of CRPC as per the inclusion criteria were included in the study and were stratified in four quartiles on the basis of time to CRPC (time to castration resistance [TTCR]) development. Early CRPC (1st quartile, TTCR = 6-12 months) and late CRPC (4th quartile, TTCR = 38-120 months) were then compared on the basis of different clinical, pathological and AR-LBD sequence to find the correlation with response duration. Median time to develop castration resistance was 25 ± 26.44 months. The mean age of the patients was 66.8 ± 9.20 years and median baseline PSA was calculated 100±685.06 ng/mL respectively. Higher Gleason score (≥7-10) was found to be significantly associated with early development of CRPC (p<0.001) and lower nadir PSA was significantly indicating late CRPC progression (p<0.005). No mutations were found in androgen receptor exon-5, 6, 7 except a homozygous mutation in the 7th intronic region, which is involved in splice variants formation playing noteworthy role in CRPC development. Time for metastatic PCa to CRPC ranges from 6-120 months revealing its heterogeneous nature. Early age presentation in the clinic and high initial PSA and high grade (GS>7) at diagnosis were positively associated with early CRPC while lower nadir PSA was correlated with late CRPC progression. No remarkable genomic mutations were discovered. Therefore, more data are needed and further research is required with large no. of patients to discover the predictive prognostic biomarkers for better patients' management.

Sex hormone receptors, calcium-binding protein and Yap1 signaling regulate sex-dependent liver cell proliferation following partial hepatectomy.

Partial hepatectomy (PH) is commonly used to treat patients with hepatocellular carcinoma. The recovery of patients from PH depends on the initiation of liver regeneration, a process that mainly relies on liver cell proliferation. As sex affects the human liver regeneration progress, we investigated sex disparity in PH-induced liver regeneration in adult zebrafish. We found that, after PH, males began liver regeneration earlier than females in terms of liver cell proliferation and liver mass recovery, and this was associated with earlier activation of Yap1 signaling in male than female livers. We also found that androgen receptors regulated the sex-biased liver regeneration in a Yap1-dependent manner and that activated estrogen receptors are responsible for the later onset of female hepatocyte proliferation. Furthermore, we identified that S100A1, a calcium-binding protein, regulates the sex disparity in liver regeneration, as heterozygous S100A1 knockout inhibited Yap1 activity in male livers and delayed hepatocyte proliferation in males following PH. Thus, multiple pathways and/or their interplays contribute to the sex disparity in liver regeneration, suggesting that sex-biased therapeutic strategies are required for patients who have received PH-based therapies.

228 (PB216): Discovery of Androgen Metabolism Enhancing Androgen Receptor Antagonists for the Treatment of Castration-Resistant prostate Cancer

228 (PB216): Discovery of Androgen Metabolism Enhancing Androgen Receptor Antagonists for the Treatment of Castration-Resistant prostate Cancer

Statin use and oncological outcomes in a propensity-matched cohort of nonmetastatic castration resistant prostate cancer patients of the ARAMIS trial

IntroductionWhile observational studies suggest favorable associations between statin use and prostate cancer (CaP) outcomes, data from randomized-controlled trials remain inconclusive. Our study explores the relationship between statin use and survival outcomes in the context of the phase III ARAMIS study, a trial of darolutamide in the treatment of nonmetastatic castration-resistant prostate cancer. MethodsWe reviewed all 1,509 patients in the ARAMIS trial. Statin use was identified at baseline. Statin users were matched 1:2 with nonusers using a propensity score matching model. The primary endpoint was metastasis-free survival (MFS). Kaplan-Meier curves were plotted for MFS comparing statin users and nonusers across ARAMIS trial arms. A multivariate Cox proportional hazards model was fitted using the propensity-matched cohort and incorporating statin use and all covariates. ResultsOf the 1,509 patients in ARAMIS, 334 (22.1%) were statin users. We matched 297 statin users to 550 nonusers. Characteristics appeared well balanced. Among nonusers, 331 (60.3%) and 219 (39.7%) were in the ARAMIS darolutamide and placebo arms, respectively. Among statin users, 179 (60.3%) and 118 (39.7%) were in the ARAMIS darolutamide and placebo arms, respectively. Overall, we found no significant difference in MFS between statin users and nonusers (HR 1.05, 95% CI 0.80–1.38 P = .72). However, we found significant interaction between statin use and ARAMIS trial arm. Specifically, statin use had a stronger association with MFS in the placebo arm (P = 0.024). However, this is likely coincidental and due to the statin-placebo patients having higher nodal positivity than the nonusers-placebo patients (14.3% vs. 5.5%). Statin use was similarly not associated with the secondary outcomes of PSA progression-free survival (P = 0.42), time-to-pain progression (P = 0.85), or overall survival (P = 0.15). ConclusionsIn our secondary analysis of the ARAMIS trial, statin users had similar MFS and secondary outcomes compared to nonusers. These results suggest pursuing further statin synergies with amide-based androgen receptor axis target agents may not be fruitful.

Prenatal exposure to di-n-butyl phthalate promotes RIPK1-regulated necroptosis of uroepithelial cells and induces hypospadias through the epithelial-mesenchymal transition process in newborn male rats

Maternal exposure to di-n-butyl phthalate (DBP) has been linked to the induction of hypospadias; however, the underlying mechanism remains unclear. Necroptosis is reported to be implicated in developmental malformations. This study aimed to investigate the underlying mechanism of necroptosis in the development of hypospadias. DBP was dissolved in corn oil, and pregnant rats were administered a precisely measured dose of DBP (750mg/kg/day) via gastric intubation from gestation day 14 to 18. Control rats received only corn oil. The day of birth was considered postnatal day (PND) 1. Male hypospadias rats were identified on PND 7. Genital tubercle tissues were collected and stored at −80°C for subsequent PCR analysis, cryopreserved in liquid nitrogen for western blot, or fixed in formalin for immunohistochemistry (IHC) staining. IHC staining and western blot analysis revealed increased expression of RIPK1 and necroptosis markers in genital tubercle (GT) tissue compared to the control group. Additionally, higher levels of EMT and impaired androgen receptor expression were observed in GT tissue. Exposure to increased DBP concentrations in rat primary uroepithelial cells (PUCs) led to elevated ROS production. Necroptosis markers and EMT expression levels were upregulated in PUCs following DBP incubation. Notably, treatment with DBP combined with necrostatin-1, a necroptosis inhibitor, reduced the expression of EMT markers and ROS production compared to DBP treatment alone. In vitro studies further revealed that DBP-induced necroptosis promoted the degradation of E-cadherin through the ubiquitin-proteasome pathway in PUCs. Our findings suggest that maternal exposure to DBP promotes necroptosis in uroepithelial cells by elevating ROS level and EMT status. Thus, necroptosis may play an essential role in the development of hypospadias.

Prostate Cancer: A Review of Genetics, Current Biomarkers and Personalised Treatments.

Prostate cancer is the second leading cause of cancer deaths in men, second only to lung cancer. Despite this, diagnosis and prognosis methods remain limited, with effective treatments being few and far between. Traditionally, prostate cancer is initially tested for through a prostate serum antigen (PSA) test and a digital rectum examination (DRE), followed by confirmation through an invasive prostate biopsy. The DRE and biopsy are uncomfortable for the patient, so less invasive, accurate diagnostic tools are needed. Current diagnostic tools, along with genes that hold possible biomarker uses in diagnosis, prognosis and indications for personalised treatment plans, were reviewed in this article. Several genes from multiple families have been identified as possible biomarkers for disease, including those from the MYC and ETS families, as well as several tumour suppressor genes, Androgen Receptor signalling genes and DNA repair genes. There have also been advances in diagnostic tools, including MRI-targeted and liquid biopsies. Several personalised treatments have been developed over the years, including those that target metabolism-driven prostate cancer or those that target inflammation-driven cancer. Several advances have been made in prostate cancer diagnosis and treatment, but the disease still grows year by year, leading to more and more deaths annually. This calls for even more research into this disease, allowing for better diagnosis and treatment methods and a better chance of patient survival.

Prior Local Therapy and First-Line Apalutamide in Patients With Nonmetastatic Castration-Resistant Prostate Cancer

Preclinical studies suggest that exposure to prostate-directed local therapy (LT) may influence the efficacy of subsequent systemic therapy including androgen receptor pathway inhibitors. However, there is insufficient clinical evidence to support this premise in patients with nonmetastatic castrate-resistant prostate cancer (nmCRPC). To determine whether exposure to prior prostate-directed LT (radical prostatectomy [RP], radiation therapy [RT], or both) played any effect-modifying role in the treatment effect of apalutamide on metastasis-free survival (MFS) and overall survival (OS) in patients with nmCRPC. This post hoc secondary analysis used individual patient data from SPARTAN (Study of Apalutamide [ARN-509] in Men With Non-Metastatic Castration-Resistant Prostate Cancer), a phase 3, double-blinded, placebo-controlled randomized clinical trial conducted at 332 sites in 26 countries. Between October 14, 2013, and December 15, 2016, patients with nmCRPC and a prostate-specific antigen doubling time of 10 months or less were randomly assigned to apalutamide vs placebo; all patients received androgen deprivation therapy. The final data analysis was performed on December 31, 2023. Prior prostate-directed LT. Separate Cox proportional hazards regression models were constructed for OS and MFS, which included prior LT, treatment group, and an interaction term, in addition to a minimally sufficient set of confounders. Adjusted hazard ratios (HRs) with 95% CIs for MFS and OS were determined for the apalutamide groups with or without prior LT. Among the 1179 evaluable patients included in this analysis, 795 received prior LT and 384 did not. The median age of patients with and without prior LT was 70 (IQR, 45-90) years and 75 (IQR, 50-95) years, respectively. The median follow-up was 52.0 (IQR, 51.5-52.8) months. A differential treatment effect of apalutamide on MFS was observed between patients with and without prior LT (P for interaction = .009), with greater benefits for those with prior LT (adjusted HR, 0.22 [95% CI, 0.17-0.27]) compared with those without prior LT (adjusted HR, 0.35 [95% CI, 0.25-0.51]). However, there was insufficient evidence of a differential treatment effect on OS among subgroups stratified by exposure to prior LT (P for interaction = .23), with improved OS in the subgroup with prior LT (adjusted HR, 0.72 [95% CI, 0.57-0.92]) but no significant difference in OS in the subgroup without prior LT (adjusted HR, 0.92 [95% CI, 0.64-1.31]). This post hoc analysis of the SPARTAN trial provides evidence of an interaction between prior LT and apalutamide in patients with nmCRPC, with a clinically significant and more favorable treatment effect from apalutamide on MFS among patients with prior LT. Further studies are needed to validate these findings. ClinicalTrials.gov Identifier: NCT01946204.

Dissecting the Significance of Acid Phosphatase 1 Gene Alterations in Prostate Cancer.

The acid phosphatase 1 (ACP1) gene encodes low-molecular-weight protein tyrosine phosphatase, which is overexpressed in prostate cancer (PC) and a potential therapeutic target. We analyzed ACP1 expression in primary/metastatic PC and its association with molecular profiles and clinical outcomes. NextGen sequencing of DNA (592-gene/whole-exome sequencing)/RNA(whole-transcriptome sequencing) was performed for 5,028 specimens. ACP1-High/ACP1-Low expression was defined as quartile (Q4/1) of RNA transcripts per million (TPM). DNA mutational profiles were analyzed for ACP1-quartile-stratified samples. Gene set enrichment analysis was used for Hallmark collection of pathways. PD-L1+(≥2+, ≥5%; SP142) was tested by immunohistochemistry. Tumor microenvironment's (TME) immune cell fractions were estimated by RNA deconvolution/quanTIseq. Overall survival (OS) was assessed from initial diagnosis/treatment initiation to death/last follow-up. We included 3,058 (60.8%) samples from the prostate, 634 (12.6%) from lymph node metastases (LNMs), and 1,307 (26.0%) from distant metastases (DMs). ACP1 expression was higher in LNM/DM than prostate (49.8/47.9 v 44.1 TPM; P < .0001). TP53 mutations were enriched in ACP1-Q4 (37.9%[Q4] v 27.0%[Q1]; P < .001) among prostate samples. Pathways associated with cell cycle regulation and oxidative phosphorylation were enriched in ACP1-Q4, whereas epithelial-mesenchymal transition and tumor necrosis factor-alpha signaling via nuclear factor kappa-light-chain-enhancer of activated B-cell pathways were enriched in ACP1-Q1. Neuroendocrine and androgen receptor signaling was increased in ACP1-Q4. M2 macrophages and natural killer cell fractions were increased, whereas T cells and M1 macrophages were decreased in ACP1-Q4. While OS differences between ACP1-Q1/Q4 were not statistically significant, there was a trend for worse OS among ACP1-Q4 prostate samples (Q4 v Q1: hazard ratio [HR], 1.19 [95% CI, 0.99 to 1.42]; P = .06) and DM (HR, 1.12 [95% CI, 0.93 to 1.36]; P = .22) but not LNM (HR, 0.98 [95% CI, 0.74 to 1.29]; P = .87). ACP1-High tumors exhibit a distinct molecular profile and cold TME, highlighting ACP1's potential role in PC pathogenesis and novel therapeutic targeting.

79 (PB067): Identification of biomarkers of response and the mechanism of action of a selective androgen receptor modulator in estrogen receptorpositive breast cancer patient-derived xenografts

79 (PB067): Identification of biomarkers of response and the mechanism of action of a selective androgen receptor modulator in estrogen receptorpositive breast cancer patient-derived xenografts

Optimizing triple therapy in patients with metastatic hormone-sensitive prostate cancer

Triple therapy with docetaxel, androgen deprivation therapy (ADT) and androgen receptor pathway inhibitors (ARPIs) has demonstrated survival benefits in patients with metastatic hormone-sensitive prostate cancer (mHSPC), especially in those with high-risk disease. However, once the use of ADT and docetaxel is established, guidelines do not clearly specify which ARPI is most appropriate. In this work, a literature review to identify phase III clinical trials, systematic reviews, meta-analyses, and clinical practice guidelines on triple therapy in mHSPC was carried out. Evidence and recommendations were qualitatively reviewed to provide guidelines on the most suitable ARPI based on patient risk, disease volume, and nature of metastases (synchronous or metachronous). This review aims to update the previously published consensus on the optimal pharmacological treatment for mHSPC and to expose the opinions of hospital pharmacy, urology and medical and radiation oncology experts.

Neuroendocrine transdifferentiation in human cancer: molecular mechanisms and therapeutic targets.

Neuroendocrine transdifferentiation (NEtD), also commonly referred to as lineage plasticity, emerges as an acquired resistance mechanism to molecular targeted therapies in multiple cancer types, predominately occurs in metastatic epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer treated with EGFR tyrosine kinase inhibitors and metastatic castration-resistant prostate cancer treated with androgen receptor targeting therapies. NEtD tumors are the lethal cancer histologic subtype with unfavorable prognosis and limited treatment. A comprehensive understanding of molecular mechanism underlying targeted-induced plasticity could greatly facilitate the development of novel therapies. In the past few years, increasingly elegant studies indicated that NEtD tumors share key the convergent genomic and phenotypic characteristics irrespective of their site of origin, but also embrace distinct change and function of molecular mechanisms. In this review, we provide a comprehensive overview of the current understanding of molecular mechanism in regulating the NEtD, including genetic alterations, DNA methylation, histone modifications, dysregulated noncoding RNA, lineage-specific transcription factors regulation, and other proteomic alterations. We also provide the current management of targeted therapies in clinical and preclinical practice.

Defining splicing factor requirements for androgen receptor variant synthesis in advanced prostate cancer.

Resistance to androgen receptor (AR)-targeted therapies represent a major challenge in prostate cancer (PC). A key mechanism of treatment resistance in patients who progress to castrate-resistant PC (CRPC) is the generation of alternatively spliced androgen receptor variants (AR-Vs). Unlike full-length AR (FL-AR) isoforms, AR-Vs are constitutively active and refractory to current receptor-targeting agents hence drive tumour progression. Identifying regulators of AR-V synthesis may therefore provide new therapeutic opportunities in combination with conventional AR-targeting agents. Our understanding of AR transcript splicing, and the factors that control the synthesis of AR-Vs, remains limited. While candidate-based approaches have identified a small number of AR-V splicing regulators, an unbiased analysis of splicing factors important for AR-V generation is required to fill an important knowledge gap and furnish the field with novel and tractable targets for PC treatment. To that end, we conducted a bespoke CRISPR screen to profile splicing factor requirements for AR-V synthesis. MFAP1 and CWC22 were shown to be required for the generation of AR-V mRNA transcripts and their depletion resulted in reduced AR-V protein abundance and cell proliferation in several CRPC models. Global transcriptomic analysis of MFAP1-depleted cells revealed both AR-dependent and -independent transcriptional impact, including genes associated with DDR. As such, MFAP1 downregulation sensitised PC cells to ionising radiation suggesting therapeutically targeting AR-V splicing could provide novel cellular vulnerabilities which can be exploited in CRPC. Implications: We have utilised a CRISPR screening approach to identify key regulators of pathogenic AR splicing in prostate cancer.

Involvement of Sex Hormones and Their Receptors in the Pathogenesis of Classic Kaposi's Sarcoma in Xinjiang.

This study aims to examine the expression of androgen receptor (AR) and estrogen receptor (ER) in patients with classic Kaposi's sarcoma (CKS) in Xinjiang, as well as to assess the serum levels of sex hormones in these patients. The objective is to explore potential new directions and targets for diagnosing and treating CKS in Xinjiang. The case group comprised 35 patients diagnosed with CKS who presented at our hospital from 2014 to 2021. The control group consisted of 35 patients with pyogenic granuloma (PG) who visited the hospital during the same period, selected using propensity score matching (PSM). Immunohistochemistry was used to detect AR, human herpesvirus type 8 (HHV-8), and ER in paraffin-embedded tissue samples from patients diagnosed with CKS and PG. Additionally, enzyme-linked immunosorbent assay (ELISA) was used to quantitatively measure serum sex hormone levels in the 35 patients with CKS and 35 patients with PG. AR expression was relatively weak in both the CKS and PG groups, with the PG group exhibiting a slightly stronger expression than the CKS group. Conversely, the expression of ER was significantly higher in the CKS group compared to the PG group (p < 0.05). Additionally, serum testosterone (T) levels were elevated in the CKS group, while serum estradiol (E2) levels were higher in the PG group (p < 0.05). Sex hormones and their receptors are implicated in the pathogenesis of CKS in Xinjiang. The use of ER antagonists may represent a novel avenue for research and treatment of CKS.

Integrated multi-omics assessment of lineage plasticity in a prostate cancer patient with brain and dural metastases

Metastases to the brain are rare in prostate cancer. Here, we describe a patient with two treatment-emergent metastatic lesions, one to the brain with neuroendocrine prostate cancer (NEPC) histology and one to the dural membrane of adenocarcinoma histology. We performed genomic, transcriptomic, and proteomic characterization of these lesions and the primary tumor to investigate molecular features promoting these metastases. The two metastatic lesions had high genomic similarity, including TP53 mutation and PTEN deletion, with the most striking difference being the additional loss of RB1 in the NEPC lesion. Interestingly, the dural lesion expressed both androgen receptor and neuroendocrine markers, suggesting amphicrine carcinoma (AMPC). When analyzing pioneer transcription factors, the AMPC lesion exhibited elevated FOXA1 activity while the brain NEPC lesion showed elevated HOXC10, NFYB, and OTX2 expression suggesting novel roles in NEPC formation or brain tropism. Our results highlight the utility of performing multi-omic characterization, especially in rare cancer subtypes.

A boost or a redundancy? on the value of combination of androgen receptor signal inhibitor and PARP inhibitor for advanced prostate cancer

AbstractPoly (ADP-ribose) polymerase (PARP) inhibitor (PARPi), as a novel endocrine therapy, has been investigated in patients with metastatic castration-resistant prostate cancer (mCRPC) in recent years. Multiple large-scale clinical trials have consistently demonstrated that various PARP inhibitors, including olaparib, rucaparib, niraparib, and talazoparib, confer longer radiographic progression-free survival (rPFS) compared to new hormonal agents (NHA) in mCRPC patients with homologous recombination deficiency (HRD). Moreover, the incidence of grade 3 and above adverse events did not significantly increase. Additionally, when combined with androgen receptor signaling inhibitors (ARSI), olaparib, niraparib, and talazoparib have shown significant extension of rPFS but also an increased occurrence of serious adverse events in HRD-positive patients. Only PROpel yielded positive results among the homologous recombination repair (HRR) mutation negative population. Therefore, it remains uncertain whether ARSI-PARPi combination therapy should be considered as first-line treatment for mCRPC patients without HRR mutations. In this review article, we aim to elucidate the necessity and feasibility of combination therapy versus monotherapy specifically within the HRR mutant population while exploring its potential applicability to other non-HRR mutant subtypes. Furthermore, we conducted a comprehensive search on registered clinical trials at present to summarize the research progress of PARP inhibitors in prostate cancer patients at different disease stages.

Diesel exhaust particle inhalation in conjunction with high-fat diet consumption alters the expression of pulmonary SARS-COV-2 infection pathways, which is mitigated by probiotic treatment in C57BL/6 male mice

BackgroundBoth exposure to air pollutants and obesity are associated with increased incidence and severity of COVID-19 infection; however, the mechanistic pathways involved are not well-characterized. After being primed by the transmembrane protease serine 2 (TMPRSS2) or furin protease, SARS-CoV-2 uses the angiotensin-converting enzyme (ACE)-2 receptor to enter respiratory epithelial cells. The androgen receptor (AR) is known to regulate both TMPRSS2 and ACE2 expression, and neuropilin-1 (NRP1) is a proposed coreceptor for SARS-CoV-2; thus, altered expression of these factors may promote susceptibility to infection. As such, this study investigated the hypothesis that inhalational exposure to traffic-generated particulate matter (diesel exhaust particulate; DEP) increases the expression of those pathways that mediate SARS-CoV-2 infection and susceptibility, which is exacerbated by the consumption of a high-fat (HF) diet.MethodsFour- to six-week-old male C57BL/6 mice fed either regular chow or a HF diet (HF, 45% kcal from fat) were randomly assigned to be exposed via oropharyngeal aspiration to 35 µg DEP suspended in 35 µl 0.9% sterile saline or sterile saline only (control) twice a week for 30 days. Furthermore, as previous studies have shown that probiotic treatment can protect against exposure-related inflammatory outcomes in the lungs, a subset of study animals fed a HF diet were concurrently treated with 0.3 g/day Winclove Ecologic® Barrier probiotics in their drinking water throughout the study.ResultsOur results revealed that the expression of ACE2 protein increased with DEP exposure and that TMPRSS2, AR, NRP1, and furin protein expression increased with DEP exposure in conjunction with a HF diet. These DEP ± HF diet-mediated increases in expression were mitigated with probiotic treatment.ConclusionThese findings suggest that inhalational exposure to air pollutants in conjunction with the consumption of a HF diet contributes to a more susceptible lung environment to SARS-CoV-2 infection and that probiotic treatment could be beneficial as a preventative measure.

Discovery of a Highly Potent PROTAC Degrader of p300/CBP Proteins for the Treatment of Enzalutamide-Resistant Prostate Cancer.

Prostate cancer therapies against androgen receptor (AR) eventually develop lethal resistance; thus, exploring new therapeutic approaches is urgent for prostate cancer treatment. Acetyltransferase p300/CBP are key coactivators for AR-mediated transcription and represent promising therapeutic targets to inhibit AR activity in prostate cancer. We describe the design synthesis and evaluation of a new class of p300/CBP PROTAC degraders. We identified an excellent p300/CBP degrader MJP6412, which effectively induced degradation of p300/CBP proteins, downregulated AR target genes, and inhibited cell growth of human prostate cancer cell lines and enzalutamide-resistant cells with IC50 even at nanomolar concentrations. Furthermore, MJP6412 demonstrated significant inhibition of tumor growth in a VCaP xenograft model. Collectively, MJP6412 is a promising lead compound for the treatment of prostate cancer, especially enzalutamide-resistant prostate cancer.