Androgen receptor splice variants drive castration-resistant prostate cancer metastasis by activating distinct transcriptional programs

One critical mechanism through which prostate cancer (PCa) adapts to treatments targeting androgen receptor (AR) signaling is the emergence of ligand-binding domain-truncated and constitutively active AR splice variants, particularly AR-V7. While AR-V7 has been intensively studied, its ability to activate distinct biological functions compared to the full-length AR (AR-FL), and its role in regulating the metastatic progression of castration-resistant PCa (CRPC), remains unclear. Our study found that, under castrated conditions, AR-V7 strongly induced osteoblastic bone lesions, a response not observed with AR-FL overexpression. Through combined ChIP-seq, ATAC-seq, and RNA-seq analyses, we demonstrated that AR-V7 uniquely accesses the androgen-responsive elements in compact chromatin regions, activating a distinct transcription program. This program was highly enriched for genes involved in epithelial-mesenchymal transition and metastasis. Notably, we discovered that SOX9, a critical metastasis driver gene, was a direct target and downstream effector of AR-V7. Its protein expression was dramatically upregulated in AR-V7-induced bone lesions. Moreover, we found that Ser81 phosphorylation enhanced AR-V7's pro-metastasis function by selectively altering its specific transcription program. Blocking this phosphorylation with CDK9 inhibitors impaired the AR-V7-mediated metastasis program. Overall, our study has provided molecular insights into the role of AR splice variants in driving the metastatic progression of CRPC.

[Clinical, endoscopic, and pathological analyses of 14 cases of gastric adenocarcinoma of the fundic gland type]

Objective: Gastric adenocarcinoma of the fundic gland type (GA-FG) is rare and often occurs in patients who are not infected with Helicobacter pylori. The current study analyzed and summarized the clinical, endoscopic, and pathological features of GA-FG, in an effort to improve its diagnosis. Methods: Patients who were diagnosed with GA-FG and treated with endoscopic submucosal dissection (ESD) resection at the Department of Gastroenterology, First Affiliated Hospital of Zhejiang Chinese Medical University from January 1st 2020 to October 1st 2022 were included in the study. Their clinical manifestations, endoscopic features, pathological immunohistochemistry, and other characteristics were analyzed. Results: A total of 14 patients with GA-FG were included in the study, 5 males and 9 females, with a mean age of 59 years. Most had no substantial clinical manifestations. Twelve patients were H. pylori-negative, all patients underwent ESD resection, and all patients survived during the follow-up period of 13±9 months. Eleven patients had postoperative endoscopic follow-up records, and no recurrence was detected. Fifteen lesions were detected (2 were present in 1 patient). Twelve were located in the upper 1/3 of the stomach, 10 were ≤ 1 cm in diameter, 12 had a morphology of type 0-Ⅱa, 8 had visible discoloration changes, and 12 had visible vasodilation on the surface. Magnified endoscopy and narrow-band imaging indicated that 12 of the lesions had enlarged marginal crypt epithelium, without any obvious microvascular pattern abnormalities and no obvious borderline. After resection the pathological specimens were all without vascular infiltration, and there was no atrophy of the mucosa at the edge of the lesion. In immunohistochemistry analyses MUC-2 was negative in all cases. MUC5AC was negative in 11 cases, MUC-6 was positive in all cases, and Ki-67 was ≤ 5% in 12 cases. Conclusions: GA-FG is a newly identified type of gastric cancer with low malignancy and a good prognosis. Characteristic discoloration and surface dilated vessels are often evident endoscopically. Enlarged marginal crypt epithelium and no visible boundary lines are often apparent in magnification endoscopy and narrow band imaging.

China Initiative for Multi-Domain Intervention (CHINA-IN-MUDI) to Prevent Cognitive Decline: Study Design and Progress

BACKGROUND

Alzheimer's disease (AD), the most common type of irreversible dementia, is predicted to affect 152 million people by 2050. Evidence from large-scale preventive randomized controlled trials (RCTs) on modifiable risk variables in Europe has shown that multi-domain lifestyle treatments for older persons at high risk of dementia may be practical and effective. Given the substantial differences between the Chinese and European populations in terms of demographics and living conditions, direct adoption of the European program in China remains unfeasible. Although a RCT has been conducted in China previously, its participants were mainly from rural areas in northern China and, thus, are not representative of the entire nation.There is an urgent need to establish cohorts that represent different economic, cultural, and geographical situations in order to explore implementation strategies and evaluate the effects of early multi-domain interventions more comprehensively and accurately.

MEDTODS

We developed an integrated intervention procedure implemented in urban neighborhood settings, namely China Initiative for Multi-Domain Intervention (CHINA-IN-MUDI). CHINA-IN-MUDI is a 2-year multicenter open-label cluster-randomised controlled trial centered around a Chinese-style multi-domain intervention to prevent cognitive decline. Participants aged 60-80 years were recruited from a nationally representative study, i.e. China Healthy Aging and Dementia Study cohort. An external harmonization process was carried out to preserve the original FINGER design. Subsequently, we standardized a series of Chinese-style intervention programs to align with cultural and socioeconomic status. Additionally, we expanded the secondary outcome list to include genomic and proteomic analyses. To enhance adherence and facilitate implementation, we leveraged an e-health application.

RESULTS

Screening commenced in July 2022. Currently, 1,965 participants have been randomized into lifestyle intervention (n = 772) and control groups (n = 1,193). Both the intervention and control groups exhibited similar baseline characteristics. Several lifestyle and vascular risk factors were present, indicating a potential window of opportunity for intervention. The intervention will be completed by 2025.

CONCLUSIONS

This project will contribute to the evaluation of the effectiveness and safety of intervention strategies in controlling AD risk and reducing clinical events, providing a basis for public health decision-making in China.

SETD7 functions as a transcription repressor in prostate cancer via methylating FOXA1

Dysregulation of histone lysine methyltransferases and demethylases is one of the major mechanisms driving the epigenetic reprogramming of transcriptional networks in castration-resistant prostate cancer (CRPC). In addition to their canonical histone targets, some of these factors can modify critical transcription factors, further impacting oncogenic transcription programs. Our recent report demonstrated that LSD1 can demethylate the lysine 270 of FOXA1 in prostate cancer (PCa) cells, leading to the stabilization of FOXA1 chromatin binding. This process enhances the activities of the androgen receptor and other transcription factors that rely on FOXA1 as a pioneer factor. However, the identity of the methyltransferase responsible for FOXA1 methylation and negative regulation of the FOXA1-LSD1 oncogenic axis remains unknown. SETD7 was initially identified as a transcriptional activator through its methylation of histone 3 lysine 4, but its function as a methyltransferase on nonhistone substrates remains poorly understood, particularly in the context of PCa progression. In this study, we reveal that SETD7 primarily acts as a transcriptional repressor in CRPC cells by functioning as the major methyltransferase targeting FOXA1-K270. This methylation disrupts FOXA1-mediated transcription. Consistent with its molecular function, we found that SETD7 confers tumor suppressor activity in PCa cells. Moreover, loss of SETD7 expression is significantly associated with PCa progression and tumor aggressiveness. Overall, our study provides mechanistic insights into the tumor-suppressive and transcriptional repression activities of SETD7 in mediating PCa progression and therapy resistance.

Demethylation of EHMT1/GLP Protein Reprograms Its Transcriptional Activity and Promotes Prostate Cancer Progression

Epigenetic reprogramming, mediated by genomic alterations and dysregulation of histone reader and writer proteins, plays a critical role in driving prostate cancer progression and treatment resistance. However, the specific function and regulation of EHMT1 (also known as GLP) and EHMT2 (also known as G9A), well-known histone 3 lysine 9 methyltransferases, in prostate cancer progression remain poorly understood. Through comprehensive investigations, we discovered that both EHMT1 and EHMT2 proteins have the ability to activate oncogenic transcription programs in prostate cancer cells. Silencing EHMT1/2 or targeting their enzymatic activity with small-molecule inhibitors can markedly decrease prostate cancer cell proliferation and metastasis in vitro and in vivo. In-depth analysis of posttranslational modifications of EHMT1 protein revealed the presence of methylation at lysine 450 and 451 residues in multiple prostate cancer models. Notably, we found that lysine 450 can be demethylated by LSD1. Strikingly, concurrent demethylation of both lysine residues resulted in a rapid and profound expansion of EHMT1's chromatin binding capacity, enabling EHMT1 to reprogram the transcription networks in prostate cancer cells and activate oncogenic signaling pathways. Overall, our studies provide valuable molecular insights into the activity and function of EHMT proteins during prostate cancer progression. Moreover, we propose that the dual-lysine demethylation of EHMT1 acts as a critical molecular switch, triggering the induction of oncogenic transcriptional reprogramming in prostate cancer cells. These findings highlight the potential of targeting EHMT1/2 and their demethylation processes as promising therapeutic strategies for combating prostate cancer progression and overcoming treatment resistance.

Significance

In this study, we demonstrate that EHMT1 and EHMT2 proteins drive prostate cancer development by transcriptionally activating multiple oncogenic pathways. Mechanistically, the chromatin binding of EHMT1 is significantly expanded through demethylation of both lysine 450 and 451 residues, which can serve as a critical molecular switch to induce oncogenic transcriptional reprogramming in prostate cancer cells.

First Dark Matter Search with Nuclear Recoils from the XENONnT Experiment

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03)  ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3)  events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47}  cm^{2} for a WIMP mass of 28  GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

Searching for Heavy Dark Matter near the Planck Mass with XENON1T

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17}  GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

LSD1 Inhibition Disrupts Super-Enhancer-Driven Oncogenic Transcriptional Programs in Castration-Resistant Prostate Cancer

The lysine demethylase LSD1 (also called KDM1A) plays important roles in promoting multiple malignancies including both hematologic cancers and solid tumors. LSD1 targets histone and nonhistone proteins and can function as a transcriptional corepressor or coactivator. LSD1 has been reported to act as a coactivator of androgen receptor (AR) in prostate cancer and to regulate the AR cistrome via demethylation of its pioneer factor FOXA1. A deeper understanding of the key oncogenic programs targeted by LSD1 could help stratify prostate cancer patients for treatment with LSD1 inhibitors, which are currently under clinical investigation. In this study, we performed transcriptomic profiling in an array of castration-resistant prostate cancer (CRPC) xenograft models that are sensitive to LSD1 inhibitor treatment. Impaired tumor growth by LSD1 inhibition was attributed to significantly decreased MYC signaling, and MYC was found to be a consistent target of LSD1. Moreover, LSD1 formed a network with BRD4 and FOXA1 and was enriched at super-enhancer regions exhibiting liquid-liquid phase separation. Combining LSD1 inhibitors with BET inhibitors exhibited strong synergy in disrupting the activities of multiple drivers in CRPC, thereby inducing significant growth repression of tumors. Importantly, the combination treatment showed superior effects than either inhibitor alone in disrupting a subset of newly identified CRPC-specific super-enhancers. These results provide mechanistic and therapeutic insights for cotargeting two key epigenetic factors and could be rapidly translated in the clinic for CRPC patients.

SIGNIFICANCE

LSD1 drives prostate cancer progression by activating super-enhancer-mediated oncogenic programs, which can be targeted with the combination of LSD1 and BRD4 inhibitors to suppress the growth of CRPC.

[Efficacy of video-assisted thoracoscopic surgical decortication for stage Ⅲ tuberculous empyema]

Objective: To investigate the clinical efficacy, safety and feasibility of "double-portal" video-assisted thoracoscopic surgical(VATS) decortication among patients with stage Ⅲ tuberculous empyema, and then to evaluate the recovery of chest deformity. Method: This study was a single center retrospective study. A total of 49 patients with stage Ⅲ tuberculous empyema who underwent VATS pleural decortication at the Department of Thoracic Surgery, Public Health Clinical Center of Chengdu between June 2017 and April 2021 were enrolled, including 38 males, and 11 females, aged 13-60 (27.5±10.4) years. The safety and feasibility of VATS were further evaluated. The inner circumference of the chest on sternal and xiphoid planes on chest CT scans before and 1, 3, 6, 12months after decortication were collected through the measuring software of the CT. The samples in-pair test was used to compare the changes in the chest to reflect the recovery of the chest deformity. Results: In the 49 patients, The surgical time was (186±61) min, and the volume of blood loss was (366±267) ml. There were 8 cases (16.33%) with postoperative complications during the perioperative period. Constant air leak and pneumonia were the main postoperative complications. No relapse of empyema or dissemination of tuberculosis occured during the period of follow-up. Before surgery, the inner thoracic circumference of the thorax at the level of the carina plane was (655±54) mm, and the inner thoracic circumference of the thorax at the level of the xiphoid plane was (720±69) mm. Patients were followed for 12-36 months. The inner thoracic circumference of the thoracic cavity at the level of carina was (666±51), (667±47) and (671±47) mm at the 3rd, 6th and 12th months after operation, which were significantly larger than that at the level of carina before operation (all P<0.05). The inner thoracic circumference diameter of the thoracic cavity measured at the xiphoid level at the 3rd, 6th and 12th months after the operation was (730±65), (733±63) and (735±63) mm respectively(all P<0.05).The inner thoracic circumference of the thoracic cavity increased significantly than that before surgery (P<0.05). At 6 months after operation, there was significant difference in the improvement of the inner thoracic circumference of the carina plane in patients with age less than 20 years and FEV₁% less than 80% (P=0.015, P=0.003). The improvement in the inner thoracic circumference of the carina plane in patients with pleural thickening≥8 mm compared with those with less than 8 mm was not statistically different(P=0.070). Conclusions: For some patients with stage Ⅲ tuberculous empyema, pleural decortication under thoracoscopy is safe and feasible, and can significantly restore the inner thoracic circumference of the patient's chest, improve the collapse of the patient's chest, and have significant clinical effect. The "double-portal VATS" surgical technology has the advantage of less trauma, wide operation field, large operation space and is easy to master, which is worth further exploring for clinical application.

Abstract 4729: LSD1 activates oncogenic super-enhancers in castration-resistant prostate cancer by forming nuclear condensates with BRD4

Lysine-specific demethylase (LSD1) was initially identified as a transcriptional repressor through demethylation of mono/di-methylated histone 3 lysine 4 (H3K4me1/2). Subsequent work suggests that LSD1 may trigger gene activation via demethylating H3K9me1/2 in the context of steroid receptors. Our previous studies have confirmed that LSD1 functions broadly as a coactivator of androgen receptor (AR)-regulated enhancers but retains its H3K4 demethylation function at these sites. Importantly, our recent work revealed that LSD1 regulates the accessibility of active enhancers through the interaction with FOXA1, which functions as a pioneer transcription factor by facilitating AR access to chromatin

LSD1 inhibition disrupts the global binding of FOXA1 by blocking the demethylation of K270 of FOXA1, leading to inhibition of AR binding and transcriptional activity. However, in addition to AR signaling, it remains largely unknown whether LSD1 regulates other critical oncogenic programs during prostate cancer (PCa) progression. In this study, we aimed to fully understand the functional targets of LSD1 in castration-resistant PCa (CRPC) models.

We performed a large transcriptomic profiling of CRPC patient-derived xenograft (PDX) models that are sensitive to LSD1 inhibitors. Our analyses indicated that LSD1 inhibition targeted multiples oncogenic programs, including previously known pathways such as AR, FOXA1, and E2F, and a previously undefined pathway, MYC signaling. Through single-cell RNA-seq analysis in a CRPC PDX model, we confirmed that MYC signaling was decreased in the responsive tumor cells and identified a previously unknown molecular subtype, AR+/FOXA1+/LSD1low/RB1−, which was resistant to LSD1 inhibition. It is well known that MYC is driven by super-enhancers (SEs), which are regulated by BRD4 (bromodomain and extraterminal (BET) protein). We further evaluated LSD1, FOXA1 and BRD4 ChIP-seq and defined SEs by using H3K27ac ChIP-seq followed by ROSE analysis. We found that LSD1, FOXA1, and BRD4 co-occupied at MYC SEs and BRD4 was recruited by unmethylated FOXA1 but not K270-methylated FOXA1. In addition, we observed the puncta-like formation of LSD1/BRD4 marked nuclear condensates under confocal immunofluorescence microscopy. By examining the public datasets of H3K27ac ChIP-seq of samples with different stages of PCa development, we identified a subset of SEs which were distinctly activated in CRPC. Using multiple CRPC PDXs, we revealed that combining LSD1 inhibitors with BET inhibitors exhibited strong synergy possibly via disrupting the CRPC-specific SEs.

In summary, this study reveals a novel oncogenic function of LSD1 in driving PCa progression by activating SE-driven oncogenic programs, such as MYC signaling. These results provide a strong therapeutic potential of combining inhibitors of LSD1 and BRD4 in treating CRPC.

Citation Format: Mingyu Liu, Muqing Li, Dong Han, Zifeng Wang, Wanting Han, Housheng Hansen He, Shuai Gao, Changmeng Cai. LSD1 activates oncogenic super-enhancers in castration-resistant prostate cancer by forming nuclear condensates with BRD4. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4729.

Abstract 4753: LSD1 &8211mediated FOXA2/AP1 transcription program drives lineage plasticity in prostate cancer

Background: While castration-resistant PCa (CRPC) can be further treated with second-generation androgen deprivation therapies (ADTs), the tumor can quickly generate resistance through multiple mechanisms. One critical mechanism is that tumor cells can progress to AR-indifferent stem cell-like (SCL-PCa or SCLPC) or neuroendocrine-like CRPC (NE-PCa or NEPC) through lineage plasticity. However, the underlying molecular basis remains to be determined, and clinical treatment options for these aggressive CRPC subtypes are currently limited. FOXA1 and FOXA2, which are members of the FOXA (Forkhead Box A) protein family, are pioneer transcription factors. While FOXA1 is well known for its function as a critical pioneer factor of AR and pivotal for maintaining AR signaling, the molecular function of FOXA2 in PCa cells is poorly understood despite that FOXA2 is known to be overexpressed in NEPC. Moreover, since FOXA2, like FOXA1, is currently undruggable in the clinic, there is an urgent need to decipher the molecular basis for the chromatin binding of FOXA2 and identify druggable targets that regulate FOXA2 binding and activity in the aggressive FOXA2-positive CRPC.

Methods: In the current study, we first examined the role of FOXA2 in tumorigenesis and metastasis by using various in vitro and in vivo assays including mouse subcutaneous injection and zebrafish embryo injection approaches. We then conducted integrated whole genomic transcriptome and cistrome analyses in SCLPC and NEPC cell line models to characterize the activity of FOXA2 on chromatin and to identify its collaborating transcription factors that may play specific functions in promoting SCLPC or NEPC using a series of biochemical and bioinformatic approaches.

Results: We found that FOXA2 silencing decreased the growth and metastasis of SCLPC and NEPC cells. Importantly, we discovered that FOXA2 chromatin binding is tightly associated with binding of JUN family proteins (primarily c-Jun) and FOXA2 silencing dramatically interrupted the global chromatin binding of c-Jun and FOSL1. The transcription targets of FOXA2/AP-1 are highly enriched for neuroendocrine and plasticity associated genes and associated with poor clinical outcomes. Furthermore, we also found that FOXA2 chromatin binding is globally enhanced by an epigenetic factor LSD1, and LSD1 inhibition can repress FOXA2/AP-1 activity in multiple CRPC models.

Conclusion: Overall, our data indicate that FOXA2 functions to maintain tumor growth and metastasis in SCLPC and NEPC models. Mechanistically, FOXA2 can act as a pioneer factor of AP-1 (c-Jun/FOSL1) and reprogram AP-1 transcription activity. This FOXA2/AP-1 axis is regulated by LSD1 via demethylating FOXA2 protein and LSD1 inhibition represses FOXA2-dependent CRPC tumor progression. These findings provide novel mechanistic insights into the molecular mechanisms for PCa lineage plasticity and treatment resistance.

Citation Format: Zifeng Wang, Mingyu Liu, Songqi Zhang, Muqing Li, Susan Patalano, Jill A. Macoska, Dong Han, Shuai Gao, Hansen He, Changmeng Cai. LSD1 &8211mediated FOXA2/AP1 transcription program drives lineage plasticity in prostate cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4753.

[Study of incubation period of infection with 2019-nCoV Omicron variant BA.5.1.3]

Objective: To study the incubation period of the infection with 2019-nCoV Omicron variant BA.5.1.3. Methods: Based on the epidemiological survey data of 315 COVID-19 cases and the characteristics of interval censored data structure, log-normal distribution and Gamma distribution were used to estimate the incubation. Bayes estimation was performed for the parameters of each distribution function using discrete time Markov chain Monte Carlo algorithm. Results: The mean age of the 315 COVID-19 cases was (42.01±16.54) years, and men accounted for 30.16%. A total of 156 cases with mean age of (41.65±16.32) years reported the times when symptoms occurred. The log-normal distribution and Gamma distribution indicated that the M (Q₁, Q₃) of the incubation period from exposure to symptom onset was 2.53 (1.86, 3.44) days and 2.64 (1.91, 3.52) days, respectively, and the M (Q₁, Q₃) of the incubation period from exposure to the first positive nucleic acid detection was 2.45 (1.76, 3.40) days and 2.57 (1.81, 3.52) days, respectively. Conclusions: The incubation period by Bayes estimation based on log-normal distribution and Gamma distribution, respectively, was similar to each other, and the best distribution of incubation period was Gamma distribution, the difference between the incubation period from exposure to the first positive nucleic acid detection and the incubation period from exposure to symptom onset was small. The median of incubation period of infection caused by Omicron variant BA.5.1.3 was shorter than those of previous Omicron variants.

Valgus-varus deformity induced abnormal tissue metabolism, inflammatory damage and apoptosis in broilers

1. This study explored the tissue metabolic status and the relationship with inflammation in valgus-valgus deformity (VVD) broilers with increasing age.2. Tissue and blood from VVD and healthy broilers were collected at two, four and five weeks old. A fully automated biochemical analyser, real-time PCR, HE staining and enzyme-linked immunosorbent assay were used to detect tissue metabolic indexes, mRNA levels of inflammation and apoptosis cytokines in immune organs, histological changes and serum inflammation and immune-related protein contents in VVD broilers.3. The results showed that VVD increased the levels of total protein, albumin, alanine aminotransferase at five weeks of age, aspartate aminotransferase, urea and creatine kinase in blood at two weeks of age. It upregulated the gene expression of inflammatory factors IL-1β, IL-6, IL-8, TNF-α, NF-κB and TGF-β and apoptotic factors FAS, Bcl-2, caspase-3 and 9 in immune organs; increased levels of serum proteins TNF-α, IL-1β and IL-6 and decreased levels of serum immunoglobulins IgY and CD3⁺.4. In addition, with increasing age, IL-10 gene expression gradually increased in the BF and decreased in the spleen.5. In conclusion, VVD broilers have disorders of liver and kidney metabolism, inflammation and apoptosis of immune organs and increased levels of serum inflammatory factor proteins.

Prognostic Value of Four Preimplantation Malnutrition Estimation Tools in Predicting Heart Failure Hospitalization of the Older Diabetic Patients with Right Ventricular Pacing

OBJECTIVES

The prognostic value of preimplantation nutritional status is not yet known for older diabetic patients that received right ventricular pacing (RVP). The study aimed to investigate the clinical value of the four malnutrition screening tools for the prediction of heart failure hospitalization (HFH) in older diabetic patients that received RVP.

DESIGN

Retrospective observational cohort study.

SETTING AND PARTICIPANTS

This study was conducted between January 2017 and January 2018 at the Fuwai Hospital, Beijing, China, and included older (age ≥ 65 years) diabetic patients that received RVP for the first time Measurements: The Prognostic Nutritional Index (PNI), Geriatric Nutritional Risk Index (GNRI), Naples Prognostic Score (NPS), and the Controlling Nutritional Status (CONUT) score were used to estimate the preimplantation nutritional status of the patients. Univariate and multivariate Cox proportional hazard regression analyses were performed to investigate the association between preimplantation malnutrition and HFH.

RESULTS

Overall, 231 older diabetic patients receiving RVP were included. The median follow-up period after RVP was 53 months. HFH was reported for 19.9% of the included patients. Our results showed preimplantation malnutrition for 18.2%, 15.2%, 86.6% and 66.2% of the included patients based on the PNI, GNRI, NPS, and CONUT score, respectively. The cumulative rate of HFH during follow-up period was significantly higher for patients in the preimplantation malnutrition group based on the PNI (log-rank = 13.0, P = 0.001), GNRI (log-rank = 8.5, P = 0.01), and NPS (log-rank = 15.7, P < 0.001) compared to the normal nutrition group, but was not statistically significant for those in the preimplantation malnutrition group based on the CONUT score (log-rank = 2.7, P = 0.3). As continuous variables, all the nutritional indices showed significant correlation with HFH (all P < 0.05). However, multivariate analysis showed that only GNRI was independently associated with HFH (HR = 0.97, 95% CI: 0.937-0.997, P = 0.032). As categorical variables, PNI, GNRI, and NPS showed significant correlation with HFH. After adjustment of confounding factors, moderate-to-severe degree of malnutrition was an independent predictor of HFH based on the PNI (HR = 4.66, 95% CI: 1.03-21.00, P = 0.045) and GNRI (HR = 3.02, 95% CI: 1.02-9.00, P = 0.047).

CONCLUSION

Preimplantation malnutrition was highly prevalent in older diabetic patients that received RVP. The malnutrition prediction tools, PNI and GNRI, showed significant prognostic value in accurately predicting HFH in older diabetic patients with RVP.

Abstract A021: Lysine methylation in EHMT1/GLP acts as a molecular switch to reprogram transcription networks to drive prostate cancer progression

Background: Prostate Cancer (PCa) progresses to a metastatic form of cancer called Castration-Resistant Prostate Cancer (CRPC) after treatment with androgen deprivation therapies (ADTs). Epigenetic reprogramming through altered expression and activity of histone modifier proteins is one major mechanism of tumor resistance. In particular, histone lysine methyltransferases (KMTs) and demethylases (KDMs) are important epigenetic targets in CRPC. In this study, we have focused on studying the function and regulation of Euchromatic Histone Methyltransferase 1 protein (EHMT1/GLP), which is a well-known H3K9 methyltransferase and functions in repressing gene transcription. EHMT family genes are altered in ~2-3% of primary PCa and ~10% of CRPC (primarily gene amplification) and their expression levels are significantly increased in CRPC, suggesting these proteins may have oncogenic activities in driving CRPC progression. Methods: We conducted an integrated analysis of ChIP-seq and RNA-seq analysis in LNCaP PCa cells to characterize the transcription program of EHMT1. We then performed proteomics analyses in VCaP and LNCaP PCa cells to identify post-translational modifications of EHMT1 and functionally validated the findings by generating loss-of-function mutations. We performed a histone demethylase assay to discover if EHMT1 is a substrate of LSD1 (a member of the KDM family). Moreover, we also assessed the effects of EHMT1 silencing or inhibition (in multiple PCa cell lines) on cell proliferation and metastasis in vitro using cell cycle analysis and transwell migration assay, and tumor growth and metastasis in vivo using mouse subcutaneous injection and zebrafish embryo injection approaches. Results: Our data showed that EHMT1 can transcriptionally activate multiple oncogenic pathways, including E2F and MYC signaling. Proteomic analyses revealed that EHMT1 is methylated in PCa cell lines, with dual-lysine methylation occurring at the K450/K451 sites. The histone demethylase assay showed that methylated K450, but not K451 is a potential substrate of LSD1. By generating the K450R, K451R, and K450/451R mutants, we showed that the K450/451R mutant, but not any single lysine mutants, can greatly expand EHMT1 chromatin binding independent of its H3K9 methyltransferase activity. This mutant also significantly induced EHMT1 oncogenic activity by activating E2F and MYC pathways. Moreover, EHMT1 silencing, or inhibition can significantly suppress tumor growth and metastasis. Conclusion: We have demonstrated that EHMT1 can function to activate oncogenic transcriptional programs in PCa by an H3K9-independent mechanism, possibly mediated through dual-lysine demethylation at K450/451 sites. Our data also suggest that targeting EHMT1 in CRPC may be a potential therapeutic strategy to suppress tumor growth and metastasis.

Citation Format: Anna Besschetnova, Wanting Han, Mingyu Liu, Yanfei Gao, Muqing Li, Zifeng Wang, Maryam Labaf, Susan Patalano, Kavita Venkataramani, Rachel Muriph, Jill Macoska, Kellee Siegfried-Harris, Jason Evans, Steven Balk, Shuai Gao, Dong Han, Changmeng Cai. Lysine methylation in EHMT1/GLP acts as a molecular switch to reprogram transcription networks to drive prostate cancer progression. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr A021.

Increased AR expression in castration-resistant prostate cancer rapidly induces AR signaling reprogramming with the collaboration of EZH2

Elevated androgen receptor (AR) expression is a hallmark of castration-resistant prostate cancer (CRPC) and contributes to the restoration of AR signaling under the conditions of androgen deprivation. However, whether overexpressed AR alone with the stimulation of castrate levels of androgens can be sufficient to induce the reprogramming of AR signaling for the adaptation of prostate cancer (PCa) cells remains unclear. In this study, we used a PCa model with inducible overexpression of AR to examine the acute effects of AR overexpression on its cistrome and transcriptome. Our results show that overexpression of AR alone in conjunction with lower androgen levels can rapidly redistribute AR chromatin binding and activates a distinct transcription program that is enriched for DNA damage repair pathways. Moreover, using a recently developed bioinformatic tool, we predicted the involvement of EZH2 in this AR reprogramming and subsequently identified a subset of AR/EZH2 co-targeting genes, which are overexpressed in CRPC and associated with worse patient outcomes. Mechanistically, we found that AR-EZH2 interaction is impaired by the pre-castration level of androgens but can be recovered by the post-castration level of androgens. Overall, our study provides new molecular insights into AR signaling reprogramming with the engagement of specific epigenetic factors.

The health system and health impacts of primary healthcare reform in China: A systematic review

Background

China has undergone a comprehensive primary healthcare(PHC) reform since 2009 aiming to deliver accessible, higher-quality, and equitable healthcare. However, there is limited understanding of the effectiveness of this reform. This systematic review synthesizes evidence on health system and health impacts of this reform.

Methods

We searched 13 international databases and three Chinese databases for quantitative studies assessing the impacts of this reform published between January 2009 and March 2020. We searched for studies in English or Mandarin. Eligible study designs were RCTs, quasi-experimental studies and controlled before-after studies. We included studies that: assessed PHC policies since 2009; had geographical, temporal or population comparators; and assessed any outcome measures of health expenditures, health service utilisation, quality of care or health outcomes. Study quality was assessed using ROBINS-I, and results synthesized narratively. PROSPERO: CRD42021239991.

Results

Of 35,480 titles, 37 studies were included (27 in English and ten in Mandarin). Eight were considered at low risk of bias. The 37 studies covered all major PHC policies since 2009, but mostly focused on the essential medicine (N = 15) and financing (N = 10). The quantity and quality of studies on service delivery policies(e.g., family physician and essential health services), were low(N = 3,with moderate or serious risk of bias). 17 studies found that the PHC reforms promoted primary care utilisation. Its impacts on quality and health improvement appear limited to people with chronic diseases(N = 11). Evidence on primary care costs and OOPs were not clear. Some evidence showed that the reforms were pro-equity with benefits accrued in disadvantaged regions and groups.

Conclusions

Comprehensive PHC reforms can deliver some benefits related to utilisation and health for high-risk and vulnerable populations. Policymakers should continue to prioritize PHC to achieve Universal Health Coverage.

Key messages

• The finding suggests that large-scale and comprehensive primary healthcare reforms can deliver benefits related to utilisation and health for high-risk and vulnerable populations.

• Future research should include more robust study designs and seek to better understand the impact of major PHC reforms on quality of care, health outcomes and equity.

Search for New Physics in Electronic Recoil Data from XENONnT

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3)  events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

[Effects and mechanism of diammonium glycyrrhizinate on liver injury in severely scalded rats]

Objective: To investigate the effects and mechanism of diammonium glycyrrhizinate (DG) on liver injury in severely scalded rats. Methods: The experimental research method was used. Fifty-four female Sprague-Dawley rats aged 7-9 weeks were divided into sham injury group with simulated injury on the back, and simple scald group and scald+DG group with scald of 30% total body surface area on the back, with 18 rats in each group. Rats in sham injury group were not specially treated after injury, and rats in simple scald group and scald+DG group were rehydrated for antishock. Besides, rats in scald+DG group were injected intraperitoneally with 50 mg/kg DG at post injury hour (PIH) 1, 25, and 49. Rats in the three groups were collected, the serum content of liver function injury related indexes including aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), total protein, and albumin was measured by automatic biochemical assay analyzer, and serum content of ornithine carbamoyl transferase (OCT) was measured by enzyme-linked immunosorbent assay method at PIH 24, 48, and 72; hepatic histopathological changes at PIH 72 were observed by hematoxylin-eosin staining; the mRNA expressions of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), glucose regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), and protein kinase R-like endoplasmic reticulum kinase (PERK) in liver tissue were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction at PIH 24, 48, and 72. The protein expressions of Bcl-2, Bax, GRP78, PERK, and ATF4 in liver tissue were detected by Western blotting at PIH 72 in sham injury group and PIH 24, 48, and 72 in simple scald group and scald+DG group. The number of samples was 6 in each group at each time point. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, and Bonferroni test. Results: Compared with that in sham injury group, the serum content of AST, ALT, and LDH was significantly increased (P<0.01), and the serum content of total protein and albumin was significantly decreased (P<0.05 or P<0.01) of rats in simple scald group at all post-injury time points. Compared with those in simple scald group, the serum AST content of rats in scald+DG group at PIH 24 was decreased significantly (P<0.05); the serum AST, ALT, and LDH content of rats in scald+DG group at PIH 48 was decreased significantly (P<0.01), and the serum total protein content was increased significantly (P<0.01); the serum AST, ALT, and LDH content of rats in scald+DG group at PIH 72 was decreased significantly (P<0.01), and the serum total protein and albumin content was increased significantly (P<0.01). At PIH 24, 48, and 72, the serum OCT content of rats in simple scald group was (48.5±3.9), (40.8±2.4), and (38.7±2.0) U/L, which was significantly higher than (15.1±2.5), (15.7±2.6), and (16.4±3.7) U/L in sham injury group (P<0.01), and (39.0±4.5), (31.8±2.0), and (22.1±2.6) U/L in scald+DG group (P<0.05 or P<0.01). At PIH 72, the cells in liver tissue of rats in sham injury group had normal morphology and regular arrangement, with no obvious inflammatory cell infiltration; the cells in liver tissue of rats in simple scald group had disordered arrangement, diffuse steatosis, and moderate inflammatory cell infiltration; the cells in liver tissue of rats in scald+DG group arranged regularly, with scattered steatosis and a small amount of inflammatory cell infiltration. Compared with those in sham injury group, the Bcl-2 mRNA (P<0.05 or P<0.01) and protein expressions of liver tissue were significantly decreased, and the mRNA (P<0.01) and protein expressions of Bax were significantly increased in rats in simple scald group at PIH 24, 48, and 72. Compared with those in simple scald group, the mRNA (P<0.05) and protein expressions of Bax in liver tissue of rats in scald+DG group were decreased significantly at PIH 48; the mRNA (P<0.01) and protein expressions of Bax in liver tissue of rats in scald+DG group were significantly decreased, and the mRNA (P<0.01) and protein expressions of Bcl-2 were significantly increased at PIH 72. Compared with those in sham injury group, the mRNA (P<0.05 or P<0.01) and protein expressions of ATF4, GRP78, and PERK in liver tissue were significantly increased in rats in simple scald group at all post-injury time points. Compared with those in simple scald group, the mRNA (P<0.01) and protein expressions of ATF4 in liver tissue of rats in scald+DG group at PIH 48 were significantly decreased, and the mRNA (P<0.05 or P<0.01) and protein expressions of ATF4, GRP78, and PERK were significantly decreased in liver tissue of rats in scald+DG group at PIH 72. Conclusions: DG can effectively reduce the degree of liver injury in rats after severe scald, and the mechanism may involve alleviating endoplasmic reticulum stress and mitigating mitochondrial damage.

[Progress in clinical diagnosis and treatment of gallbladder cancer]

Due to the lack of effective early diagnosis and treatment, gallbladder cancer(GBC) remains a malignant tumor with extremely high malignancy and poor prognosis. Therefore, high quality studies are required to break through the bottleneck in GBC diagnosis and treatment. This article reviewed the domestic and foreign GBC research published in 2021, presenting a comprehensive summary of the important advances in the field of clinical diagnosis and treatment. Latest epidemiological data and risk factors, emerging diagnostic methods of peripheral blood laboratory tests and imaging, new pathologic classification system, hot topics and controversies of surgical treatment as well as the dynamics of systemic treatment of GBC are reviewed in the article. The present findings may contribute to a more efficient means of diagnosis and treatment for GBC and hold the promise of improved outcomes for patients with GBC.

[Survival analysis since diagnosis of HIV-positive injecting drug users aged 15 years and above in China]

Objective: To understand death's mortality and risk factors among HIV-positive injecting drug users (IDU) aged 15 or above in China and provide further reference to future prevention and treatment policies. Method: Retrospective cohort study was conducted to calculate the mortality rate of HIV-positive IDU based on HIV/AIDS Comprehensive Response Information Management System. Cox proportion hazards regression model was performed to assess the risk factors for deaths. The Excel 2019 and SPSS 22.0 software was used for data cleaning and statistical analysis. Results: Between 2001 and 2020, 119 209 HIV-positive IDU were reported with 59 094 deaths. The all-cause mortality rate was 6.96 per 100 person-years (py), and the AIDS-related mortality rate was 1.91 per 100 py, with a decreasing trend over the years. Multivariate Cox regression indicated for all-cause death risks of HIV-positive IDU, compared with those baseline T⁺ lymphocyte cells (CD4) counts above 500 cells/μl, the HR (95%CI) of those CD4 counts untested, between 0-199, 200-349, 350-500 cells/μl was 2.85 (2.78-2.93), 2.47 (2.40-2.54), 1.58 (1.53-1.62) and 1.24 (1.21-1.28) respectively. The HR (95%CI) of antiretroviral treatment (ART) naïve was 7.13 (6.99-7.27) compared with those under ART. The HR (95%CI) of methadone maintenance treatment (MMT) naïve was 1.07 (1.04-1.10) compared to those receiving MMT. As for AIDS-related death risks, compared with baseline T+ lymphocyte cell CD4 counts >500 cells/μl, the HR (95%CI) of those CD4 counts untested, between 0-199, 200-349, 350-500 cells/μl was 3.26 (3.08-3.46), 5.54 (5.24-5.85), 2.35 (2.21-2.50) and 1.41 (1.32-1.50). HR (95%CI) of ART naïve was 5.96(5.74-6.18) compared to those under ART. Conclusions: Further efforts should be made timely on diagnosis, treatment, and harm reduction programs such as MMT for improvement compliance to reduce mortality risks of HIV-positive IDU.

Exploiting the tumor-suppressive activity of the androgen receptor by CDK4/6 inhibition in castration-resistant prostate cancer

The androgen receptor (AR) plays a pivotal role in driving prostate cancer (PCa) development. However, when stimulated by high levels of androgens, AR can also function as a tumor suppressor in PCa cells. While the high-dose testosterone (high-T) treatment is currently being tested in clinical trials of castration-resistant prostate cancer (CRPC), there is still a pressing need to fully understand the underlying mechanism and thus develop treatment strategies to exploit this tumor-suppressive activity of AR. In this study, we demonstrate that retinoblastoma (Rb) family proteins play a central role in maintaining the global chromatin binding and transcriptional repression program of AR and that Rb inactivation desensitizes CRPC to the high-dose testosterone treatment in vitro and in vivo. Using a series of patient-derived xenograft (PDX) CRPC models, we further show that the efficacy of high-T treatment can be fully exploited by a CDK4/6 inhibitor, which strengthens the chromatin binding of the Rb-E2F repressor complex by blocking the hyperphosphorylation of Rb proteins. Overall, our study provides strong mechanistic and preclinical evidence on further developing clinical trials to combine high-T with CDK4/6 inhibitors in treating CRPC.

Inhibition of EZH2 transactivation function sensitizes solid tumors to genotoxic stress

Drugs that block the activity of the methyltransferase EZH2 are in clinical development for the treatment of non-Hodgkin lymphomas harboring EZH2 gain-of-function mutations that enhance its polycomb repressive function. We have previously reported that EZH2 can act as a transcriptional activator in castration-resistant prostate cancer (CRPC). Now we show that EZH2 inhibitors can also block the transactivation activity of EZH2 and inhibit the growth of CRPC cells. Gene expression and epigenomics profiling of cells treated with EZH2 inhibitors demonstrated that in addition to derepressing gene expression, these compounds also robustly down-regulate a set of DNA damage repair (DDR) genes, especially those involved in the base excision repair (BER) pathway. Methylation of the pioneer factor FOXA1 by EZH2 contributes to the activation of these genes, and interaction with the transcriptional coactivator P300 via the transactivation domain on EZH2 directly turns on the transcription. In addition, CRISPR-Cas9-mediated knockout screens in the presence of EZH2 inhibitors identified these BER genes as the determinants that underlie the growth-inhibitory effect of EZH2 inhibitors. Interrogation of public data from diverse types of solid tumors expressing wild-type EZH2 demonstrated that expression of DDR genes is significantly correlated with EZH2 dependency and cellular sensitivity to EZH2 inhibitors. Consistent with these findings, treatment of CRPC cells with EZH2 inhibitors dramatically enhances their sensitivity to genotoxic stress. These studies reveal a previously unappreciated mechanism of action of EZH2 inhibitors and provide a mechanistic basis for potential combination cancer therapies.

[Epidemiological characteristics of newly reported HIV-infected adolescents aged 15-17 years outside school in China, 2011-2019]

Objective: To understand the epidemiological characteristics of HIV-infected adolescents outside school in China and provide reference to targeted prevention and control of HIV infection in this population. Methods: All the HIV-infected adolescents aged 15-17 years outside school reported during 2011-2019 were included this study. The information about their demographics, transmission routes and migration were collected from HIV/AIDS Comprehensive Response Information Management System. The χ² test was done for comparison among groups. The Joinpoint 4.9.0 software was applied to the annual percent change (APC) for time trends analysis using the Joinpoint regression model. The Excel 2019 and SPSS 22.0 software were used for data cleaning and statistical analysis. Results: A total of 4 919 HIV-infected adolescents aged 15-17 years outside school were reported accumulatively in China between 2011 and 2019, accounting for 63.4% (4 919/7 757) of total reported HIV-infected cases in this age group. Analysis on trend revealed that the new HIV infection diagnosis rate has become stable since 2016 (APC=2.5%, P=0.173) after the increase between 2011 and 2015 (APC=36.4%, P<0.001). The migration across provinces was discovered in 13.9% (684/4 919) of the HIV-infected adolescents outside school. Males, workers, and those diagnosed in detention centers or transmitted by injecting drugs or homosexual contacts accounted for a larger proportion in migrated cases compared with non-migrated cases. The adolescents outside school mainly got HIV infected by sexual contacts route, in which 66.5% (280/421) of the males were infected by homosexual contacts, while 97.8% (182/186) of the females were infected by heterosexual contacts in 2019. Conclusions: HIV-infected adolescents aged 15-17 years outside school were mainly infected by sexual contacts. However, adolescents outside school have low awareness of sexual health and high mobility, to whom close attention should be paid to improve their awareness of sexual health and to provide them with appropriate HIV infection prevention and treatment service.

RB1 loss in castration-resistant prostate cancer confers vulnerability to LSD1 inhibition

Genomic loss of RB1 is a common alteration in castration-resistant prostate cancer (CRPC) and is associated with poor patient outcomes. RB1 loss is also a critical event that promotes the neuroendocrine transdifferentiation of prostate cancer (PCa) induced by the androgen receptor (AR) signaling inhibition (ARSi). The loss of Rb protein disrupts the Rb-E2F repressor complex and thus hyperactivates E2F transcription activators. While the impact of Rb inactivation on PCa progression and linage plasticity has been previously studied, there is a pressing need to fully understand underlying mechanisms and identify vulnerabilities that can be therapeutically targeted in Rb-deficient CRPC. Using an integrated cistromic and transcriptomic analysis, we have characterized Rb activities in multiple CRPC models by identifying Rb directly regulated genes and revealed that Rb has distinct binding sites and targets in CRPC with different genomic backgrounds. Significantly, we show that E2F1 chromatin binding and transcription activity in Rb-deficient CRPC are highly dependent on LSD1/KDM1A, and that Rb inactivation sensitizes CRPC tumor to the LSD1 inhibitor treatment. These results provide new molecular insights into Rb activity in PCa progression and suggest that targeting LSD1 activity with small molecule inhibitors may be a potential treatment strategy to treat Rb-deficient CRPC.

Impact of Removing Race Adjustment When Estimating GFR on Chronic Kidney Disease Staging

Introduction/Objective

Determination of glomerular filtration rate (GFR) is essential in assessment of kidney function, particularly in patients with chronic kidney disease (CKD). Formulas were developed to calculate estimated GFR (eGFR), as direct measurement is cumbersome and not amenable to routine monitoring. CKD-EPI is the most widely used formula for eGFR, using parameters of serum creatinine, gender, race, and age. A race adjustment was added from an unfounded assumption that Black patients have more muscle mass, increasing their eGFR by about 16%. There is concern on the impact of “correcting” for Black race on patient management, utility of eGFR, and its possible contribution to healthcare disparities. This study examined the impact of eliminating race adjustment from the CKD- EPI formula on CKD staging in patients at a large safety-net hospital in an academic medical center.

Methods/Case Report

80090 serum creatinine values from 56676 adult patients (31.4% Black, 67.5% female, median age 51 yrs) were collected from the electronic medical record (Epic, Verona, WI) over a 16-month timeframe. Values were excluded if they lacked age, gender, self-identified race, or serum creatinine. eGFR was calculated using the CKD-EPI equation with and without race modifier, and CKD staging was performed using 2012 Kidney Disease: Improving Global Outcomes guidelines.

Results (if a Case Study enter NA)

In our cohort, only 50.8% of Black patients are in CKD1, indicative of no CKD, compared to 67.9% of non-Black patients. Given that these two cohorts are demographically similar, this shows a discrepancy in kidney function even before removing the race adjustment. After removal of the race modifier, 28.1% of Black patients were reclassified into a more severe CKD stage. The most restaging occurred from CKD3A to 3B (39%).

Conclusion

Many Black patients in our study were reclassified to a more severe CKD stage, with the highest percentage of patients restaged to CKD3B, which would have attracted clinical attention for nephrology referral. We recommend removal of the race adjustment in eGFR, given its basis in the incorrect belief in biological differences between races. It perpetuates systemic racism and discrimination in healthcare, and its removal will provide more equitable care and reduce healthcare disparities. Future studies should examine the increase in resources required to provide adequate medical care to patients who will be placed into a more severe CKD stage.

Abstract 2317: Targeting prostate cancer super enhancers by co-inhibiting LSD1 and BRD4

In prostate cancer (PCa) cells, “pioneer” factor FOXA1 resides at distal enhancers enriched with histone 3 lysine 4 methylation (H3K4me) and lysine 27 acetylation (H3K27ac). FOXA1 is capable of remodeling the compact chromatin to facilitate androgen receptor (AR) recruitment. Recent studies revealed overexpression of FOXA1 caused by frequent structural alterations in the lethal stage of PCa, namely castration-resistant PCa(CRPC), suggesting FOXA1 as a critical target in CRPC. However, a lack of targetable domain hinders the effective targeting of FOXA1. Our recent (epi)genomic profiling study revealed that lysine-specific demethylase (LSD1) and FOXA1 co-occupy at active enhancers in PCa cells and LSD1 demethylase activity is required for FOXA1 chromatin binding. LSD1 inhibition can quickly and drastically reduce FOXA1 global binding and concurrently impair the “openness” of enhancers, leading to disrupted AR cistrome. Mechanistically, we demonstrated that this activator function of LSD1 is mediated through directly demethylating K270 of FOXA1. By testing an array of adenocarcinoma CRPC in vivo models, we further showed that the efficacy of LSD1 inhibitors may be correlated with FOXA1 levels. Collectively, these results provide the molecular reasoning on co-targeting the epigenetic regulators that are important for promoting AR activity in treating CRPC.

Furthermore, we have found that LSD1, FOXA1, and BRD4 (a Bromodomain and Extra-Terminal motif (BET) protein) co-occupy the super enhancers characterized by distinguishable high levels of H3K4me2 and H3K27ac in PCa cells. Super enhancers have been found to drive oncogenic transcription program in PCa. As an active enhancer marker and an important AR coactivator, BRD4 recognizes H3K27ac signal and promotes the initiation and elongation steps in gene transcription process. Herein, we focus on the potential synergism of combined targeting of LSD1 and BRD4. We found that FOXA1 interacted with BRD4 in different cell lines and patient-derived xenograft (PDX) tumor tissues. In line with this association, either LSD1 inhibitors or BET inhibitors could decrease FOXA1 and BRD4 chromatin binding. Characterization of the physical interaction is an ongoing study. We found that the combinational treatment lead to a more effective reduction of AR transcriptional activity than either single treatment. The PCa cell proliferation in vitro was also more profoundly inhibited by combined therapy. More importantly, we demonstrated this synergism in both 22RV1 xenograft and PDX LuCaP35CR in the castrated mice, with a lower dose of LSD1 inhibitor and BET inhibitor (both in clinical trials) which did not induce overt toxicity in the animals. Currently, we are performing RNA-seq studies to identify the convergent downstream pathways by this co-treatment. In summary, our study provides important pre-clinical insights for targeting the CRPC enhancers by combining inhibitors of LSD1 and BRD4.

Citation Format: Shuai Gao, Muqing Li, Mingyu Liu, Dong Han, Zifeng Wang, Wanting Han, Changmeng Cai. Targeting prostate cancer super enhancers by co-inhibiting LSD1 and BRD4 [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 2317.

Abstract 2152: EHMT1 activity to repress neuroendocrine differentiation of prostate cancer is mediated by dual lysine-methylation

Background: Lysine methylation is an important post-translational regulation on histones, but its molecular functions on non-histone proteins remain largely unknown. In a pilot study, we identified novel lysine methylations at non-histone proteins in prostate cancer (PCa) cells through an affinity pull-down assay. EHMT1/GLP, containing monomethylated K450 and K451, was one of these proteins, and it was known to repress transcription through methylating histone 3 lysine 9 (H3K9). EHMT1 and EHMT2/G9a are members of the REST (NRSF) repressor complex, that includes LSD1/CoREST/HDACs and represses neuronal genes in non-neuronal cells. Loss of function for this complex has been indicated as a mechanism to drive neuroendocrine (NE) transition of PCa. We hypothesize that the K450/451 methylations may inhibit the activity of EHMT1 and that LSD1 and other lysine demethylase(s) may sequentially demethylate these lysines and thus induce EHMT1 activity to silence the expression of NE related genes.

Methods: LNCaP stable cell lines overexpressing doxycycline-regulated V5-tagged EHMT1-WT, K450R, K451R, and K450/451R were generated. We performed ChIP-seq analyses of V5 and H3K9me2, and RNA-seq analyses in all four cell lines treated with/out doxycycline. We also conducted in vitro demethylation assays to examine whether LSD1 directly demethylates EHMT1. Moreover, we performed co-immunoprecipitation assays to determine the effect of LSD1 inhibition on the interaction of LSD1 with EHMT1. Neuronal target gene expression was examined through ChIP and mRNA analysis.

Results: Using mass-spectrometry analysis, we confirmed K450 and K451 methylations of EHMT1 in LNCaP PCa cell line. The demethylation assays indicated that methylated K450 but not K451 is a potential substrate of LSD1. Moreover, LSD1 interacts with K450/451R mutant but not EHMT1-WT. Importantly, only K450/451R mutant had a significant increase of chromatin binding in V5 and elevated levels of H3K9me2 compared to the weak chromatin binding seen in WT, K450R and K451R. Analyses in RNA-Seq revealed that the K450/K451R mutant repressed genes enriched for neuronal pathways, which was not seen in WT, K450R or K451R.

Conclusions: Our studies suggest that both K450 and K451 of EHMT1 are methylated in PCa cells. K450-methylation of EHMT1 can be specifically demethylated by LSD1, but this alone is not sufficient to induce the chromatin recruitment of EHMT1. However, demethylation at both K450/K451 can dramatically increase the chromatin binding of EHMT1, which subsequently represses neuronal pathways. This mechanism may be particularly important for maintaining the cell lineage of adenocarcinoma of PCa and loss of this demethylation might lead to the emergence of NE-like PCa.

Citation Format: Anna Besschetnova, Wanting Han, Mingyu Liu, Dong Han, Shuai Gao, Changmeng Cai. EHMT1 activity to repress neuroendocrine differentiation of prostate cancer is mediated by dual lysine-methylation [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 2152.

Abstract 2509: RB1-loss in castration-resistant prostate cancer reprograms androgen receptor signaling and confers vulnerability to LSD1 inhibition

Background: Retinoblastoma protein (Rb) functions to repress the transcription activity of E2Fs by forming an Rb-E2F repressor complex and the hyperphosphorylation of Rb during G1/S cell cycle transition results in its disassociation with E2Fs, thus inducing E2F-dependent transcription of DNA replication and cell cycle. Genomic RB1-loss is frequently occurred in castration-resistant prostate cancer (CRPC) (~10-15%) and is significantly associated with poor clinical outcomes. RB1-loss is also more frequently found in CRPC with neuroendocrine features (CRPC-NE) (~45-50%). However, it remains unclear on the global activities of Rb-E2F repressor complex functions in modulating transcriptional networks in CRPC. In this study, we performed a comprehensive analysis to functionally characterize the activities of Rb-E2F in multiple CRPC models and aimed to identify vulnerabilities in CRPC with RB1-loss. Methods: C4-2 cells (PTEN-loss, p53 positive) stably infected with doxycycline-inducible lentiviral shRNA against RB1 were generated. VCaP cells (PTEN positive, p53 R248W mut) that transfected with siRNAs against RB1 (siRB) were also examined. The chromatin landscape of Rb-E2F complex was determined by Rb ChIP-seq. Rb-E2F transcriptome was obtained from RNA-seq analysis in the C4-2 stable line treated with/out doxycycline and VCaP cells with siRB. An integrated analysis combines the ChIP-seq and RNA-seq data was also performed to characterize the direct targets of Rb-E2F. Furthermore, we have also assessed the effect of RB1 loss on AR transcriptional program using AR ChIP-seq and RNA-seq in cells treated with/out DHT. Results: Using an integrated cistromic and transcriptomic analysis, we have characterized Rb-E2F activities in multiple CRPC models by identifying the Rb-E2F directly regulated genes. Our results revealed that Rb-E2F has distinct binding sites and targets in TP53-mutated CRPC, and that the expression of Rb-E2F directly repressed genes is increased in the neuroendocrine (NE) subtype of CRPC. Furthermore, we have found that loss of Rb expression redistributes the chromatin binding of androgen receptor (AR), leading to the transcriptional activation of a subset of genes that are increased in CRPC-NE. Remarkably, we have found that the chromatin binding of E2F1 is regulated by an epigenetic factor LSD1/KDM1A (a lysine-specific demethylase that demethylates histone and non-histone proteins) and loss of Rb sensitizes the E2F signaling to the regulation by LSD1. Importantly, LSD1 inhibitor treatment was more effective in CRPC xenograft tumors with RB silencing. Conclusion: Taken together, these results characterized the direct transcriptomic changes in RB1-loss CRPC, indicated a reprogramming of AR signaling by loss of RB1, and suggested LSD1 as a potential therapeutic target in RB1-loss CRPC or CRPC-NE by modulating chromatin binding of E2Fs.

Citation Format: Wanting Han, Mingyu Liu, Dong Han, Muqing Li, Anthia A. Toure, Susan C. Patalano-Salsman, Jill A. Macoska, Shuai Gao, Changmeng Cai. RB1-loss in castration-resistant prostate cancer reprograms androgen receptor signaling and confers vulnerability to LSD1 inhibition [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 2509.

Metal-Insulator Transition and Emergent Gapped Phase in the Surface-Doped 2D Semiconductor 2H-MoTe_{2}

Artificially created two-dimensional (2D) interfaces or structures are ideal for seeking exotic phase transitions due to their highly tunable carrier density and interfacially enhanced many-body interactions. Here, we report the discovery of a metal-insulator transition (MIT) and an emergent gapped phase in the metal-semiconductor interface that is created in 2H-MoTe_{2} via alkali-metal deposition. Using angle-resolved photoemission spectroscopy, we found that the electron-phonon coupling is strong at the interface as characterized by a clear observation of replica shake-off bands. Such strong electron-phonon coupling interplays with disorder scattering, leading to an Anderson localization of polarons which could explain the MIT. The domelike emergent gapped phase could then be attributed to a polaron extended state or phonon-mediated superconductivity. Our results demonstrate the capability of alkali-metal deposition as an effective method to enhance the many-body interactions in 2D semiconductors. The surface-doped 2H-MoTe_{2} is a promising candidate for realizing polaronic insulator and high-T_{c} superconductivity.

Susceptibility-Associated Genetic Variation in NEDD9 Contributes to Prostate Cancer Initiation and Progression

Although American men of European ancestry represent the largest population of patients with prostate cancer, men of African ancestry are disproportionately affected by prostate cancer, with higher prevalence and worse outcomes. These racial disparities in prostate cancer are due to multiple factors, but variations in genomic susceptibility such as SNP may play an important role in determining cancer aggressiveness and treatment outcome. Using public databases, we have identified a prostate cancer susceptibility SNP at an intronic enhancer of the neural precursor expressed, developmentally downregulated 9 (NEDD9) gene, which is strongly associated with increased risk of patients with African ancestry. This genetic variation increased expression of NEDD9 by modulating the chromatin binding of certain transcription factors, including ERG and NANOG. Moreover, NEDD9 displayed oncogenic activity in prostate cancer cells, promoting prostate cancer tumor growth and metastasis in vitro and in vivo. Together, our study provides novel insights into the genetic mechanisms driving prostate cancer racial disparities. SIGNIFICANCE: A prostate cancer susceptibility genetic variation in NEDD9, which is strongly associated with the increased risk of patients with African ancestry, increases NEDD9 expression and promotes initiation and progression of prostate cancer.See related commentary by Mavura and Huang, p. 3764.

[Analysis on death trend in AIDS patients and related risk factors in China]

Objective: To understand the basic characteristics of death cases, analyze the death trends in AIDS patients and the risk factors in China and provide evidence for the development of AIDS prevention and control strategy. Methods: The data were collected from the national basic information system of HIV/AIDS. The information of the cases in AIDS phase were used. The death number and mortality trends in AIDS cases were described, and Cox Proportion Hazards Regression Model was constructed to assess hazard ratios (HR) for independent variables. Results: By the end of 2019, a total of 582 472 AIDS cases, including 168 391 deaths, had been reported in China. Among the death cases, males accounted for 76.8% (129 343/168 391), heterosexual contact was the main transmission route, accounting for 60.9% (102 516/168 391). The proportion of the death cases who had ever received ART was 54.0% (90 888/168 391). The inter-quartile (P₂₅, P₇₅) of first CD₄^＋T cells counts (CD₄) was 34 cells/μl, 240 cells/μl. Up to 43.5% (73 191/168 391) of the deaths occurred within one year after diagnosis. From 2007 to 2019, the annual death number increased from 5 485 to 18 737, the mortality rates decreased form 10.9%% to 4.3%. The average time interval from diagnosis to death ranged from 1.4 year to 4.0 years, showing increase trend by year. The results of Cox regression analysis showed that older age (50- years old: HR=1.50; ≥65 years old: HR=2.00), being male (HR=1.44)、being in minority ethnic group (HR=1.10), having lower first CD₄ levels (0- cells/μl, HR=2.73;200- cells/μl, HR=1.33; 350- cells/μl,HR=1.13), heterosexual transmission route (HR=1.64) and injecting drug use (HR=1.79) were the risk factors related to deaths in AIDS patients. The higher educational levels (junior middle school: HR=0.86, senior high school and above: HR=0.59) and receiving antiviral treatrment (HR=0.09) were protective factors. Conclusions: The number of death cases increased, meanwhile the mortality rates decrease year by year in AIDS patients in China during 2007-2019. It is necessary to strengthen the early detection and treatment of AIDS to reduce the mortality.

[Estimation of newly HIV infection trend by using the back-calculation method in Honghe Hani and Yi autonomous prefecture]

Objective: Using the changing patterns of CD(4)(+) lymphocytes (CD(4)) counts of HIV/AIDS cases, we tried to estimate the number of newly infected HIV in Honghe Hani and Yi autonomous prefecture (Honghe prefecture) Yunnan province, and to provide reference for evaluating the trend of local HIV epidemic. Methods: Among diagnosed HIV infections, those who were at ≥15 years old, having available initial CD(4) records of testing, initiating antiviral therapy before the end of 2018, were selected from the case reporting system of Honghe prefecture, Yunnan province. Both Depletion model of the square root on CD(4) and the time of infection were used to back-calculate the seroconversion time of each individual. Both direct probability distribution method and life table method were used to calculate the distribution rates of diagnosis and the weight of delay. The number of diagnoses over the years was used to reversely estimate the total number of newly HIV infections. Results: At the end of 2018, the total number of HIV infections was estimated 35 977 with the rate of diagnosis as 77.50% in Honghe prefecture of Yunnan province. The number of new HIV infections appeared as 23 792 in 2008-2018. Cumulatively, the number of new HIV infections was 12 185 up to 2007. The estimated number of new HIV infections decreased from 2 602 in 2008 to 1 480 in 2018. The weight of diagnostic delay decreased from 5.49 in one year to 1.00 in 20 years, and the diagnosis rate increased from 18.2% to 100.0% during 20 years. Conclusion: In Honghe prefecture of Yunnan province, the number of newly infection showed a declining trend but the diagnostic rate was still far from reaching the "first 90% target" . It is expected to expand the timeliness on detection and case-finding so as to reduce the risk of HIV transmission.

A Novel Mechanism to Induce BRCAness in Cancer Cells

Cancer cells with germline deleterious mutations of BRCA1 or BRCA2 are deficient in homologous recombination repair and therefore sensitive to PARP inhibitor treatment. However, wild-type BRCA1/2-expressing cells with defects in other DNA damage repair pathway components may also exhibit "BRCAness," which in combination with PARP inhibition can similarly induce synthetic lethality. In this issue of Cancer Research, Luo and colleagues report a novel mechanism by which BRCA1 protein degradation in response to DNA double-strand breaks is regulated by prolyl isomerase Pin1. Inactivation of Pin1 can establish BRCAness in cancer cells and thus sensitize cells to PARP inhibitor treatment.See related articles by Luo et al., p. 3033.

[Characteristics and trends of newly reported HIV infection in young students in China, 2010-2019]

Objective: To analyze the characteristics and trends of newly reported HIV infection cases in young students in China between 2010 and 2019 and provide evidence for the formulation of AIDS prevention and control measures in young students. Methods: Data were collected from the Basic Web-based HIV/AIDS Case Reporting System. The HIV infection cases in students aged 15-24 years reported between 2010 and 2019 were selected. Their basic characteristics were described, and Joinpoint Regression Model was used to analyze the temporal trends of new diagnosis rates in different age groups. Results: A total of 23 307 HIV/AIDS cases were reported in young students, the male to female ratio was 33.9∶1 (22 640∶667), and the mean age was (19.9±2.05) years. The temporal trends of new diagnosis rates showed two stages, it increased rapidly between 2010 and 2015 (annual percentage changes, APC=32.1), and kept stable between 2015 and 2019 (APC=0.1, P>0.05). The new diagnosis rates in all age groups showed increasing trends between 2010 and 2015, and the APC of age group 15-17 years was highest (30.2). Between 2015 and 2019, the new diagnosis rates in age group 23-24 years showed decreasing trend (APC=-17.0). The transmission route was mainly homosexual contact for males, and heterosexual contact for females. For most heterosexual transmission cases, they were infected through non-marital or non-commercial heterosexual contact. The male cases mainly came from HIV voluntary counseling and testing clinics, but the female cases were mainly found in hospitals. The male cases had higher mean first CD(4)(+)T cells counts (CD(4)) compared with female cases (t=3.917, P=0.000). Conclusions: The overall increase trend of newly reported HIV infection in young students slowed slow down trend between 2010 and 2019, but the newly reported HIV infections in age group 15-17 years still showed an increase trend. It is necessary to carry out sex health education effectively in young students to reduce the high-risk sexual behavior and expand HIV test coverage in students.

Chromatin binding of FOXA1 is promoted by LSD1-mediated demethylation in prostate cancer

FOXA1 functions as a pioneer transcription factor by facilitating the access to chromatin for steroid hormone receptors, such as androgen receptor and estrogen receptor^1-4, but mechanisms regulating its binding to chromatin remain elusive. LSD1 (KDM1A) acts as a transcriptional repressor by demethylating mono/dimethylated histone H3 lysine 4 (H3K4me1/2)^5,6, but also acts as a steroid hormone receptor coactivator through mechanisms that are unclear. Here we show, in prostate cancer cells, that LSD1 associates with FOXA1 and active enhancer markers, and that LSD1 inhibition globally disrupts FOXA1 chromatin binding. Mechanistically, we demonstrate that LSD1 positively regulates FOXA1 binding by demethylating lysine 270, adjacent to the wing2 region of the FOXA1 DNA-binding domain. Acting through FOXA1, LSD1 inhibition broadly disrupted androgen-receptor binding and its transcriptional output, and dramatically decreased prostate cancer growth alone and in synergy with androgen-receptor antagonist treatment in vivo. These mechanistic insights suggest new therapeutic strategies in steroid-driven cancers.

Band insulator to Mott insulator transition in 1T-TaS2

1T-TaS₂ undergoes successive phase transitions upon cooling and eventually enters an insulating state of mysterious origin. Some consider this state to be a band insulator with interlayer stacking order, yet others attribute it to Mott physics that support a quantum spin liquid state. Here, we determine the electronic and structural properties of 1T-TaS₂ using angle-resolved photoemission spectroscopy and X-Ray diffraction. At low temperatures, the 2π/2c-periodic band dispersion, along with half-integer-indexed diffraction peaks along the c axis, unambiguously indicates that the ground state of 1T-TaS₂ is a band insulator with interlayer dimerization. Upon heating, however, the system undergoes a transition into a Mott insulating state, which only exists in a narrow temperature window. Our results refute the idea of searching for quantum magnetism in 1T-TaS₂ only at low temperatures, and highlight the competition between on-site Coulomb repulsion and interlayer hopping as a crucial aspect for understanding the material’s electronic properties.

1T-TaS2 possesses complex electronic phase behaviors in transition-metal di-chalcogenides, undergoing several charge-ordered phases before finally into an insulating state of unknown origin. Here, the authors determine its electronic and structural properties experimentally, revealing its origin.

Isostructural Spin-Density-Wave and Superconducting Gap Anisotropies in Iron-Arsenide Superconductors

When passing through a phase transition, electronic system saves energy by opening energy gaps at the Fermi level. Delineating the energy gap anisotropy provides insights into the origin of the interactions that drive the phase transition. Here, we report the angle-resolved photoemission spectroscopy (ARPES) study on the detailed gap anisotropies in both the tetragonal magnetic and superconducting phases in Sr_{1-x}Na_{x}Fe_{2}As_{2}. First, we found that the spin-density-wave (SDW) gap is strongly anisotropic in the tetragonal magnetic phase. The gap magnitude correlates with the orbital character of Fermi surface closely. Second, we found that the SDW gap anisotropy is isostructural to the superconducting gap anisotropy regarding to the angular dependence, gap minima locations, and relative gap magnitudes. Our results indicate that the superconducting pairing interaction and magnetic interaction share the same origin. The intraorbital scattering plays an important role in constructing these interactions resulting in the orbital-selective magnetism and superconductivity in iron-based superconductors.