Acquisitions of behavioral health treatment facilities from 2010 to 2021.

Private equity (PE) and other for-profit ownership of behavioral health (mental health and substance use) treatment facilities have become increasingly prevalent, but data on these acquisitions are not readily available. In this study, we describe a novel database that contains information on the universe of behavioral health acquisitions that occurred between 2010 and 2021. We found that the frequency of behavioral health facilities involved in acquisitions increased substantially, from 32 facilities in 2010 to 1330 in 2021. The total number of facilities involved in acquisitions was 2806. Most of these facilities provided outpatient services only (N = 2073) and offered only mental health services (N = 1428). Private equity-backed acquisitions accounted for around 60% of all acquisition activity (N = 1678 facilities PE, N = 1128 facilities other for-profit). 25% of acquired facilities were located within 20 miles of one another (N = 561), 50% occurred within 80 miles (N = 1403), and 75% occurred within 319 miles (N = 2104). Future research should evaluate the effects of this consolidation on behavioral healthcare access, quality, spending, and patient outcomes.

Nursing home finances associated with real estate investment trust and private equity investments.

In 2021, real estate investment trusts (REITs) and private equity (PE) held investments in 1915 (16%) and 1569 (13%) US nursing homes (NHs), respectively. We created a database of REIT and PE investments in NHs, merged it with Medicare Cost Report data (2011-2019), and used a difference-in-differences approach within an event-study framework to compare NH spending and financial performance before and after REIT or PE investment to NHs that did not receive REIT or PE investment. REIT investments were associated with higher total wages (3%), total nursing wages (3%; both logged, per resident day [PRD]), and current ratio (81%). PE investments were associated with lower net patient service revenue (7%), total expenses (7%), and total wages (8%; all logged, PRD). The impact of REIT and PE investments in NHs may vary in different market conditions, as may occur in the current environment of low, falling NH profits, potentially higher minimum staffing requirements, and rising interest rates. Therefore, it is important for stakeholders to understand the impact of these large, growing investments on the financial performance of NHs.

New CMS Nursing Home Ownership Data: Major Gaps And Discrepancies.

Nursing home ownership has become increasingly complicated, partly because of the growth of facilities owned by institutional investors such as private equity (PE) firms and real estate investment trusts (REITs). Although the ownership transparency and accountability of nursing homes have historically been poor, the Biden administration's nursing home reform plans released in 2022 included a series of data releases on ownership. However, our evaluation of the newly released data identified several gaps: One-third of PE and fewer than one-fifth of REIT investments identified in the proprietary Irving Levin Associates and S&P Capital IQ investment data were present in Centers for Medicare and Medicaid Services (CMS) publicly available ownership data. Similarly, we obtained different results when searching for the ten top common owners of nursing homes using CMS data and facility survey reports of chain ownership. Finally, ownership percentages were missing in the CMS data for 82.40 percent of owners in the top ten chains and 55.21 percent of owners across all US facilities. Although the new data represent an important step forward, we highlight additional steps to ensure that the data are timely, accurate, and responsive. Transparent ownership data are fundamental to understanding the adequacy of public payments to provide patient care, enable policy makers to make timely decisions, and evaluate nursing home quality.

Discovery and validation of genes driving drug-intake and related behavioral traits in mice.

Substance use disorders are heritable disorders characterized by compulsive drug use, the biological mechanisms for which remain largely unknown. Genetic correlations reveal that predisposing drug-naïve phenotypes, including anxiety, depression, novelty preference and sensation seeking, are predictive of drug-use phenotypes, thereby implicating shared genetic mechanisms. High-throughput behavioral screening in knockout (KO) mice allows efficient discovery of the function of genes. We used this strategy in two rounds of candidate prioritization in which we identified 33 drug-use candidate genes based upon predisposing drug-naïve phenotypes and ultimately validated the perturbation of 22 genes as causal drivers of substance intake. We selected 19/221 KO strains (8.5%) that had a difference from control on at least one drug-naïve predictive behavioral phenotype and determined that 15/19 (~80%) affected the consumption or preference for alcohol, methamphetamine or both. No mutant exhibited a difference in nicotine consumption or preference which was possibly confounded with saccharin. In the second round of prioritization, we employed a multivariate approach to identify outliers and performed validation using methamphetamine two-bottle choice and ethanol drinking-in-the-dark protocols. We identified 15/401 KO strains (3.7%, which included one gene from the first cohort) that differed most from controls for the predisposing phenotypes. 8 of 15 gene deletions (53%) affected intake or preference for alcohol, methamphetamine or both. Using multivariate and bioinformatic analyses, we observed multiple relations between predisposing behaviors and drug intake, revealing many distinct biobehavioral processes underlying these relationships. The set of mouse models identified in this study can be used to characterize these addiction-related processes further.

Screening for problematic opioid use in the emergency department: Comparison of two screening measures.

Study objective: Earlier intervention for opioid use disorder (OUD) may reduce long-term health implications. Emergency departments (EDs) in the United States treat millions with OUD annually who may not seek care elsewhere. Our objectives were (1) to compare two screening measures for OUD characterization in the ED and (2) to determine the proportion of ED patients screening positive for OUD and those who endorse other substance use to guide future screening programs. Methods: A cross-sectional study of randomly selected adult patients presenting to three Midwestern US EDs were enrolled, with duplicate patients excluded. Surveys were administered via research assistant and documented on tablet devices. Demographics were self-reported, and OUD positivity was assessed by the DSM 5 checklist and the WHO ASSIST 3.1. The primary outcome was the concordance between two screening measures for OUD. Our secondary outcome was the proportion of ED patients meeting OUD criteria and endorsed co-occurring substance use disorder (SUD) criteria. Results: We enrolled 1305 participants; median age of participants was 46 years (range 18-84), with 639 (49.0%) Non-Hispanic, White, and 693 (53.1%) female. Current OUD positivity was identified in 17% (222 out of 1305) of the participants via either DSM-5 (two or more criteria) or ASSIST (score of 4 or greater). We found moderate agreement between the measures (kappa = 0.56; Phi coefficient = 0.57). Of individuals screening positive for OUD, 182 (82%) endorsed criteria for co-occurring SUD. Conclusions: OUD is remarkably prevalent in ED populations, with one in six ED patients screening positive. We found a high prevalence of persons identified with OUD and co-occurring SUD, with moderate agreement between measures. Developing and implementing clinically feasible OUD screening in the ED is essential to enable intervention.

Association of Private Equity Firm Acquisition of Ophthalmology Practices with Medicare Spending and Use of Ophthalmology Services.

PURPOSE: Private equity (PE) firms increasingly are acquiring ophthalmology practices; little is known of their influence on care use and spending. We studied changes in use and Medicare spending after PE acquisition. DESIGN: Retrospective cohort study. PARTICIPANTS: Seven hundred sixty-two clinicians in 123 practices acquired by PE between 2017 and 2018 and 34 807 clinicians in 20 549 never-acquired practices. METHODS: We analyzed Medicare fee-for-service claims (2012-2019) combined with a novel national database of PE acquisitions of ophthalmology practices using a difference-in-differences method within an event study framework to compare changes after a practice was acquired with changes in practices that were not acquired. MAIN OUTCOME MEASURES: Numbers of beneficiaries seen; intravitreal injections and medications used for injections; and spending on ophthalmologist and optometrist services, ancillary services, and intravitreal injections. RESULTS: Comparing PE-acquired with nonacquired practices showed a 23.92% increase (n = 4.20 beneficiaries; 95% confidence interval [CI], 1.73-6.67) in beneficiaries seen per PE optometrist per quarter and no change for ophthalmologists, while spending per beneficiary increased 5.06% ($9.66; 95% CI, -2.82 to 22.14). Spending on clinician services decreased 1.62% (-$2.37; 95% CI, -5.78 to 1.04), with ophthalmologist services increasing 5.46% ($17.70; 95% CI, -2.73 to 38.15) and optometrists decreasing 4.60% (-$5.76; 95% CI, -9.17 to -2.34) per beneficiary per quarter. Ancillary services decreased 7.56% (-$2.19; 95% CI, 4.19 to -0.22). Intravitreal injection costs increased 25.0% ($20.02; 95% CI, -1.38 to 41.41) with the number increasing 5.10% (1.83; 95% CI, -0.1 to 3.80). There was a 74.09% increase (8.38 injections; 95% CI, 0.01-16.74) in ranibizumab and a 12.91% decrease (-3.40 injections; 95% CI, -6.86 to 0.07) in bevacizumab after acquisition. The event study showed consistent and often statistically significant increases in ranibizumab injections and decreases in bevacizumab injections after acquisition. CONCLUSIONS: Although not all results reached statistical significance, this study suggested that PE acquisition of practices showed little or no overall effect on use or total spending, but increased the number of unique patients seen per optometrist and the use of expensive intravitreal injections. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

United States' Nursing Home Finances: Spending, Profitability, and Capital Structure.

Little is known about nursing home (NH) financial status in the United States even though most NH care is publicly funded. To address this gap, this descriptive study used 2019 Medicare cost reports to examine NH revenues, expenditures, net income, related-party expenses, expense categories, and capital structure. After a cleaning process for all free-standing NHs, a study population of 11,752 NHs was examined. NHs had total net revenues of US$126 billion and a profit of US$730 million (0.58%) in 2019. When US$6.4 billion in disallowed costs and US$3.9 billion in non-cash depreciation expenses were excluded, the profit margin was 8.84 percent. About 77 percent of NHs reported US$11 billion in payments to related-party organizations (9.54% of net revenues). Overall spending for direct care was 66 percent of net revenues, including 27 percent on nursing, in contrast to 34 percent spent on administration, capital, other, and profits. Finally, NHs had long-term debts that outweighed their total available financing. The study shows the value of analyzing cost reports. It indicates the need to ensure greater accuracy and completeness of cost reports, financial transparency, and accountability for government funding, with implications for policy changes to improve rate setting and spending limits.

Changes in Diagnoses and Site of Care for Patients Receiving Hospice Care From Agencies Acquired by Private Equity Firms and Publicly Traded Companies.

Importance: Private equity firms and publicly traded companies have been acquiring US hospice agencies; an estimated 16% of US hospice agencies are owned by private equity (PE) firms or publicly traded companies (PTC). Objective: To examine the association of PE and PTC acquisitions of hospices with Medicare patients' site of care and clinical diagnoses. Design, Setting, and Participants: This cohort study of US hospice agencies used a novel national database of acquisitions merged with the Medicare Post-Acute Care and Hospice Public Use File for 2013 to 2020. Changes in sites of care and patient characteristics for hospice agencies acquired by PE or PTCs were compared with changes for patients in nonacquired for-profit hospice agencies. Exposure: Private equity and publicly traded company acquisitions. Main Outcomes and Measures: This study used a difference-in-differences approach within an event-study framework to examine the association of PE and PTC acquisitions of hospice agencies with changes in patient diagnoses and sites of care. Dependent variables were annual hospice-level measures of the Hierarchical Condition Category (HCC) score and proportion of patients diagnosed with cancer or dementia. Sites of care included the proportion of patients receiving hospice care in their personal home, nursing home, or assisted living facility. Results: A total of 158 hospice agencies acquired by PEs, 250 acquired by PTCs, and 1559 other for-profit hospice agencies were included. Preacquisition, hospice agencies that would later be acquired by PE or PTC served a mean (IQR) 30.1% (12.0%-44.0%) and 29.4% (13.0%-43.0%) of their patients in nursing homes respectively, a greater proportion compared with the 27.1% (8.0%-43.8%) served by for-profit hospices that were never acquired. Agencies acquired by PE between 2014 and 2019 saw a significant relative increase of 5.98% in dementia patients (1.38 percentage points; 95% CI, 0.35-2.40 percentage points; P = .008). In PTC-owned hospices, the proportion of patients receiving care at home increased by 5.26% (2.98 percentage points; 95% CI, 1.46-4.51 percentage points; P < .001), the proportion of dementia patients rose by 13.49% (3.11 percentage points; 95% CI, 2.14-4.09 percentage points; P < .001), and the HCC score decreased by 1.37% (-3.19 percentage points; 95% CI, -5.92 to -0.47 percentage points; P = .02). Conclusions and Relevance: These findings suggest that PE and PTCs select patients and sites of care to maximize profits.

Substance Use and Mental Health Screening Within an Emergency Department-Based HIV Screening Program: Outcomes From 1 Year of Implementation.

INTRODUCTION: The emergency department (ED) may be an optimal setting to screen for substance use disorders (SUDs) and co-occurring psychiatric disorders (CODs). We report on the frequency of problematic substance use and comorbid elevated mental health symptoms detected during a 1-year implementation period of an ED-based SUD/COD screening approach within an established ED HIV screening program. METHODS: Patients (N = 1,924) were approached by dedicated HIV screening staff in an urban, Midwestern ED. Patients first completed measures assessing problematic alcohol (Alcohol Use Disorder Identification Test-Concise [AUDIT-C]) and substance use across 10 categories of substances (National Institute on Drug Abuse-Modified Alcohol, Smoking, and Substance Involvement Screening Test [NIDA-Modified ASSIST]). Patients with positive alcohol and/or substance use screens completed measures assessing symptoms of depression (Patient Health Questionnaire-9 [PHQ-9]), anxiety (Generalized Anxiety Disorder-7 [GAD-7]), and post-traumatic stress disorder (PTSD) (PTSD Checklist-Civilian [PCL-C]). RESULTS: Patients were predominantly male (60.3%) with a mean age of 38.1 years (SD = 13.0); most identified as White (50.8%) or Black (44.8%). A majority (58.5%) had a positive screen for problematic alcohol and/or other substance use. Of those with a positive substance use screen (n = 1,126), 47.0% had a positive screen on one or more of the mental health measures with 32.1% endorsing elevated depressive symptoms, 29.6% endorsing elevated PTSD-related symptoms, and 28.5% endorsing elevated anxiety symptoms. CONCLUSIONS: Among those receiving ED HIV screening, a majority endorsed problematic alcohol and/or other substance use and co-occurring elevated mental health symptoms. Substance use and mental health screening programs that can be integrated within other ED preventive services may enhance the identification of individuals in need of further assessment, referral, or linkage to substance use treatment services.

DISCOVERY AND VALIDATION OF GENES DRIVING DRUG-INTAKE AND RELATED BEHAVIORAL TRAITS IN MICE.

Substance use disorders (SUDs) are heritable disorders characterized by compulsive drug use, but the biological mechanisms driving addiction remain largely unknown. Genetic correlations reveal that predisposing drug-naïve phenotypes, including anxiety, depression, novelty preference, and sensation seeking, are predictive of drug-use phenotypes, implicating shared genetic mechanisms. Because of this relationship, high-throughput behavioral screening of predictive phenotypes in knockout (KO) mice allows efficient discovery of genes likely to be involved in drug use. We used this strategy in two rounds of screening in which we identified 33 drug-use candidate genes and ultimately validated the perturbation of 22 of these genes as causal drivers of substance intake. In our initial round of screening, we employed the two-bottle-choice paradigms to assess alcohol, methamphetamine, and nicotine intake. We identified 19 KO strains that were extreme responders on at least one predictive phenotype. Thirteen of the 19 gene deletions (68%) significantly affected alcohol use three methamphetamine use, and two both. In the second round of screening, we employed a multivariate approach to identify outliers and performed validation using methamphetamine two-bottle choice and ethanol drinking-in-the-dark protocols. We identified 15 KO strains that were extreme responders across the predisposing drug-naïve phenotypes. Eight of the 15 gene deletions (53%) significantly affected intake or preference for three alcohol, eight methamphetamine or three both (3). We observed multiple relations between predisposing behaviors and drug intake, revealing many distinct biobehavioral processes underlying these relationships. The set of mouse models identified in this study can be used to characterize these addiction-related processes further.

Whole genome analysis for 163 gRNAs in Cas9-edited mice reveals minimal off-target activity.

Genome editing with CRISPR-associated (Cas) proteins holds exceptional promise for "correcting" variants causing genetic disease. To realize this promise, off-target genomic changes cannot occur during the editing process. Here, we use whole genome sequencing to compare the genomes of 50 Cas9-edited founder mice to 28 untreated control mice to assess the occurrence of S. pyogenes Cas9-induced off-target mutagenesis. Computational analysis of whole-genome sequencing data detects 26 unique sequence variants at 23 predicted off-target sites for 18/163 guides used. While computationally detected variants are identified in 30% (15/50) of Cas9 gene-edited founder animals, only 38% (10/26) of the variants in 8/15 founders validate by Sanger sequencing. In vitro assays for Cas9 off-target activity identify only two unpredicted off-target sites present in genome sequencing data. In total, only 4.9% (8/163) of guides tested have detectable off-target activity, a rate of 0.2 Cas9 off-target mutations per founder analyzed. In comparison, we observe ~1,100 unique variants in each mouse regardless of genome exposure to Cas9 indicating off-target variants comprise a small fraction of genetic heterogeneity in Cas9-edited mice. These findings will inform future design and use of Cas9-edited animal models as well as provide context for evaluating off-target potential in genetically diverse patient populations.

Comprehensive ECG reference intervals in C57BL/6N substrains provide a generalizable guide for cardiac electrophysiology studies in mice.

Reference ranges provide a powerful tool for diagnostic decision-making in clinical medicine and are enormously valuable for understanding normality in pre-clinical scientific research that uses in vivo models. As yet, there are no published reference ranges for electrocardiography (ECG) in the laboratory mouse. The first mouse-specific reference ranges for the assessment of electrical conduction are reported herein generated from an ECG dataset of unprecedented scale. International Mouse Phenotyping Consortium data from over 26,000 conscious or anesthetized C57BL/6N wildtype control mice were stratified by sex and age to develop robust ECG reference ranges. Interesting findings include that heart rate and key elements from the ECG waveform (RR-, PR-, ST-, QT-interval, QT corrected, and QRS complex) demonstrate minimal sexual dimorphism. As expected, anesthesia induces a decrease in heart rate and was shown for both inhalation (isoflurane) and injectable (tribromoethanol) anesthesia. In the absence of pharmacological, environmental, or genetic challenges, we did not observe major age-related ECG changes in C57BL/6N-inbred mice as the differences in the reference ranges of 12-week-old compared to 62-week-old mice were negligible. The generalizability of the C57BL/6N substrain reference ranges was demonstrated by comparison with ECG data from a wide range of non-IMPC studies. The close overlap in data from a wide range of mouse strains suggests that the C57BL/6N-based reference ranges can be used as a robust and comprehensive indicator of normality. We report a unique ECG reference resource of fundamental importance for any experimental study of cardiac function in mice.

Physician Management Companies and Neonatology Prices, Utilization, and Clinical Outcomes.

BACKGROUND AND OBJECTIVES: Physician management companies (PMCs) acquire physician practices and contract with hospitals to provide physician management services. We evaluated the association between PMC-NICU affiliations and prices, spending, utilization, and clinical outcomes. METHODS: We linked commercial claims to PMC-NICU affiliations and conducted difference- in-differences analyses comparing changes in prices paid for physician services per critical or intensive care NICU day, length of the NICU stay, physician spending (total paid amount for physician services during stay), spending on hospital services (total paid amount for hospital services during stay), and clinical outcomes in PMC-affiliated versus non-PMC-affiliated NICUs. The study included 2858 infants admitted to 34 PMC-affiliated NICUs and 92 461 infants admitted to 2348 NICUs without an affiliation. RESULTS: PMC affiliation was associated with a differential increase in the mean price of the 5 most common types of critical and intensive care days in NICU admissions by $313 per day (95% confidence interval, $207-$419) for PMC-affiliated versus non- PMC-affiliated NICUs. This represents a 70.4% increase in prices, relative to the preaffiliation period PMC and non- PMC-affiliated NICU means. PMC-NICU affiliation was also associated with a differential increase in physician spending by $5161 per NICU stay (95% confidence interval, $3062-$7260), a 56.4% increase. There was no significant association between PMC-NICU affiliation and changes in length of stay, clinical outcomes, or hospital spending. CONCLUSIONS: PMC affiliation was associated with large increases in prices and total spending for NICU services, but not with changes in length of stay or adverse clinical outcomes.

Genetic Variants Associated With Opioid Use Disorder.

Genetics are presumed to contribute 30-40% to opioid use disorder (OUD), allowing for the possibility that genetic markers could be used to identify personal risk for developing OUD. We aimed to test the potential association among 180 candidate single nucleotide polymorphisms (SNPs), 120 of which were related to the dopamine reward pathway and 60 related to pharmacokinetics. Participants were randomly recruited in 2020-2021 in a cross-sectional genetic association study. Self-reported health history including Diagnostic and Statistical Manual of Mental Disorders (DSM-5) OUD criteria and buccal swabs were collected. A total of 1,301 participants were included in the analyses for this study. Of included participants, 250 met the DSM-5 criteria for ever having OUD. Logistic regression, adjusting for age and biologic sex, was used to characterize the association between each SNP and DSM-5 criteria consistent with OUD. Six SNPs found in four genes were associated with OUD: increased odds with CYP3A5 (rs15524 and rs776746) and DRD3 (rs324029 and rs2654754), and decreased odds with CYP3A4 (rs2740574) and CYP1A2 (rs2069514). Homozygotic CYP3A5 (rs15524 and rs776746) had the highest adjusted odds ratio of 2.812 (95% confidence interval (CI) 1.737, 4.798) and 2.495 (95% CI 1.670, 3.835), respectively. Variants within the dopamine reward and opioid metabolism pathways have significant positive (DRD3 and CYP3A5) and negative (CYP3A4 and CYP1A2) associations with OUD. Identification of these variants provides promising possibilities for genetic prognostic and therapeutic targets for future investigation.

Genome-wide screening reveals the genetic basis of mammalian embryonic eye development.

BACKGROUND: Microphthalmia, anophthalmia, and coloboma (MAC) spectrum disease encompasses a group of eye malformations which play a role in childhood visual impairment. Although the predominant cause of eye malformations is known to be heritable in nature, with 80% of cases displaying loss-of-function mutations in the ocular developmental genes OTX2 or SOX2, the genetic abnormalities underlying the remaining cases of MAC are incompletely understood. This study intended to identify the novel genes and pathways required for early eye development. Additionally, pathways involved in eye formation during embryogenesis are also incompletely understood. This study aims to identify the novel genes and pathways required for early eye development through systematic forward screening of the mammalian genome. RESULTS: Query of the International Mouse Phenotyping Consortium (IMPC) database (data release 17.0, August 01, 2022) identified 74 unique knockout lines (genes) with genetically associated eye defects in mouse embryos. The vast majority of eye abnormalities were small or absent eyes, findings most relevant to MAC spectrum disease in humans. A literature search showed that 27 of the 74 lines had previously published knockout mouse models, of which only 15 had ocular defects identified in the original publications. These 12 previously published gene knockouts with no reported ocular abnormalities and the 47 unpublished knockouts with ocular abnormalities identified by the IMPC represent 59 genes not previously associated with early eye development in mice. Of these 59, we identified 19 genes with a reported human eye phenotype. Overall, mining of the IMPC data yielded 40 previously unimplicated genes linked to mammalian eye development. Bioinformatic analysis showed that several of the IMPC genes colocalized to several protein anabolic and pluripotency pathways in early eye development. Of note, our analysis suggests that the serine-glycine pathway producing glycine, a mitochondrial one-carbon donator to folate one-carbon metabolism (FOCM), is essential for eye formation. CONCLUSIONS: Using genome-wide phenotype screening of single-gene knockout mouse lines, STRING analysis, and bioinformatic methods, this study identified genes heretofore unassociated with MAC phenotypes providing models to research novel molecular and cellular mechanisms involved in eye development. These findings have the potential to hasten the diagnosis and treatment of this congenital blinding disease.

The Role Of Real Estate Investment Trusts In Staffing US Nursing Homes.

In 2021 real estate investment trusts (REITs) held investments in 1,806 US nursing homes. REITs are for-profit public or private corporations that invest in income-producing properties. We created a novel database of REIT investments in US nursing homes, merged it with Medicare cost report data (2013-19), and used a difference-in-differences approach within an event study framework to compare staffing before and after a nursing home received REIT investment with staffing in for-profit nursing homes that did not receive REIT investment. REIT investment was associated with average relative staffing increases of 2.15 percent and 1.55 percent for licensed practical nurses (LPNs) and certified nursing assistants (CNAs), respectively. During the postinvestment period, registered nurse (RN) staffing was unchanged, but event study results showed a 6.25 percent decrease in years 2 and 3 after REIT investment. After the three largest REIT deals were excluded, REIT investments were associated with an overall 6.25 percent relative decrease in RN staffing and no changes in LPN and CNA staffing. Larger deals resulted in increases in LPN and CNA staffing, with no changes in RN staffing; smaller deals appeared to replace more expensive and skilled RN staffing with less expensive and skilled staff.

Inflammation Impacts Androgen Receptor Signaling in Basal Prostate Stem Cells Through Interleukin 1 Receptor Antagonist.

The majority of patients with benign prostate hyperplasia (BPH) exhibit chronic prostate inflammation and the extent of inflammation correlates with the severity of symptoms. How inflammation contributes to prostate enlargement and/or BPH symptoms and the underlying mechanisms are not clearly understood. We established a unique mouse model Prostate Ovalbumin Expressing Transgenic 3 (POET3) that mimics chronic non-bacterial prostatitis in men to study the role of inflammation in prostate hyperplasia. After the injection of ovalbumin peptide-specific T cells, POET3 prostates exhibited an influx of inflammatory cells and an increase in pro-inflammatory cytokines that led to epithelial and stromal hyperplasia. We have previously demonstrated with the POET3 model that inflammation expands the basal prostate stem cell (bPSC) population and promotes bPSC differentiation in organoid cultures. In this study, we investigated the mechanisms underlying the impact of inflammation on bPSC. We found that AR activity was enhanced in inflamed bPSC and was essential for bPSC differentiation in organoid cultures. Most importantly, we identified, for the first time, interleukin 1 receptor antagonist (IL-1RA) as a key regulator of AR in basal stem cells. IL-1RA was one of the top genes upregulated by inflammation and inhibition of IL-1RA abrogated the enhanced AR nuclear accumulation and activity in organoids derived from inflamed bPSC. The mirroring effects of IL-1RA recombinant protein and IL-1α neutralizing antibody suggest that IL-1RA may function by antagonizing IL-1α inhibition of AR expression. Furthermore, we established a lineage tracing model to follow bPSC during inflammation and under castrate conditions. We found that inflammation induced bPSC proliferation and differentiation into luminal cells even under castrate conditions, indicating that AR activation driven by inflammation in bPSC is sufficient for their proliferation and differentiation under androgen-deprived conditions. However, proliferation of the differentiated bPSC in the luminal layer significantly diminished with castration, suggesting inflammation may not maintain AR activity in stromal cells, as stromal cells deprived of androgen after castration could no longer provide paracrine growth factors essential for luminal proliferation. Taken together, we have discovered novel mechanisms through which inflammation modulates AR signaling in bPSC and induces bPSC luminal differentiation that contributes to prostate hyperplasia.

Analysis of genome-wide knockout mouse database identifies candidate ciliopathy genes.

We searched a database of single-gene knockout (KO) mice produced by the International Mouse Phenotyping Consortium (IMPC) to identify candidate ciliopathy genes. We first screened for phenotypes in mouse lines with both ocular and renal or reproductive trait abnormalities. The STRING protein interaction tool was used to identify interactions between known cilia gene products and those encoded by the genes in individual knockout mouse strains in order to generate a list of "candidate ciliopathy genes." From this list, 32 genes encoded proteins predicted to interact with known ciliopathy proteins. Of these, 25 had no previously described roles in ciliary pathobiology. Histological and morphological evidence of phenotypes found in ciliopathies in knockout mouse lines are presented as examples (genes Abi2, Wdr62, Ap4e1, Dync1li1, and Prkab1). Phenotyping data and descriptions generated on IMPC mouse line are useful for mechanistic studies, target discovery, rare disease diagnosis, and preclinical therapeutic development trials. Here we demonstrate the effective use of the IMPC phenotype data to uncover genes with no previous role in ciliary biology, which may be clinically relevant for identification of novel disease genes implicated in ciliopathies.