Developing Clinical Risk Prediction Models for Worsening Heart Failure Events and Death by Left Ventricular Ejection Fraction.

Background There is a need to develop electronic health record-based predictive models for worsening heart failure (WHF) events across clinical settings and across the spectrum of left ventricular ejection fraction (LVEF). Methods and Results We studied adults with heart failure (HF) from 2011 to 2019 within an integrated health care delivery system. WHF encounters were ascertained using natural language processing and structured data. We conducted boosted decision tree ensemble models to predict 1-year hospitalizations, emergency department visits/observation stays, and outpatient encounters for WHF and all-cause death within each LVEF category: HF with reduced ejection fraction (EF) (LVEF <40%), HF with mildly reduced EF (LVEF 40%-49%), and HF with preserved EF (LVEF ≥50%). Model discrimination was evaluated using area under the curve and calibration using mean squared error. We identified 338 426 adults with HF: 61 045 (18.0%) had HF with reduced EF, 49 618 (14.7%) had HF with mildly reduced EF, and 227 763 (67.3%) had HF with preserved EF. The 1-year risks of any WHF event and death were, respectively, 22.3% and 13.0% for HF with reduced EF, 17.0% and 10.1% for HF with mildly reduced EF, and 16.3% and 10.3% for HF with preserved EF. The WHF model displayed an area under the curve of 0.76 and mean squared error of 0.13, whereas the model for death displayed an area under the curve of 0.83 and mean squared error of 0.076. Performance and predictors were similar across WHF encounter types and LVEF categories. Conclusions We developed risk prediction models for 1-year WHF events and death across the LVEF spectrum using structured and unstructured electronic health record data and observed no substantial differences in model performance or predictors except for death, despite differences in underlying HF cause.

Association Between Participation in a Heart Failure Telemonitoring Program and Health Care Utilization and Death Within an Integrated Health Care Delivery System.

BACKGROUND: The clinical usefulness of remote telemonitoring to reduce postdischarge health care use and death in adults with heart failure (HF) remains controversial. METHODS AND RESULTS: Within a large integrated health care delivery system, we matched patients enrolled in a postdischarge telemonitoring intervention from 2015 to 2019 to patients not receiving telemonitoring at up to a 1:4 ratio on age, sex, and calipers of a propensity score. Primary outcomes were readmissions for worsening HF and all-cause death within 30, 90, and 365 days of the index discharge; secondary outcomes were all-cause readmissions and any outpatient diuretic dose adjustments. We matched 726 patients receiving telemonitoring to 1985 controls not receiving telemonitoring, with a mean age of 75 ± 11 years and 45% female. Patients receiving telemonitoring did not have a significant reduction in worsening HF hospitalizations (adjusted rate ratio [aRR] 0.95, 95% confidence interval [CI] 0.68-1.33), all-cause death (adjusted hazard ratio 0.60, 95% CI 0.33-1.08), or all-cause hospitalization (aRR 0.82, 95% CI 0.65-1.05) at 30 days, but did have an increase in outpatient diuretic dose adjustments (aRR 1.84, 95% CI 1.44-2.36). All associations were similar at 90 and 365 days postdischarge. CONCLUSIONS: A postdischarge HF telemonitoring intervention was associated with more diuretic dose adjustments but was not significantly associated with HF-related morbidity and mortality.

Heterozygous midnolin knockout attenuates severity of nonalcoholic fatty liver disease in mice fed a Western-style diet high in fat, cholesterol, and fructose.

Although midnolin has been studied for over 20 years, its biological roles in vivo remain largely unknown, especially due to the lack of a functional animal model. Indeed, given our recent discovery that the knockdown of midnolin suppresses liver cancer cell tumorigenicity and that this antitumorigenic effect is associated with modulation of lipid metabolism, we hypothesized that knockout of midnolin in vivo could potentially protect from nonalcoholic fatty liver disease (NAFLD) which has become the most common cause of chronic liver disease in the Western world. Accordingly, in the present study, we have developed and now report on the first functional global midnolin knockout mouse model. Although the overwhelming majority of global homozygous midnolin knockout mice demonstrated embryonic lethality, heterozygous knockout mice were observed to be similar to wild-type mice in their viability and were used to determine the effect of reduced midnolin expression on NAFLD. We found that global heterozygous midnolin knockout attenuated the severity of NAFLD in mice fed a Western-style diet, high in fat, cholesterol, and fructose, and this attenuation in disease was associated with significantly reduced levels of large lipid droplets, hepatic free cholesterol, and serum LDL, with significantly differential gene expression involved in cholesterol/lipid metabolism. Collectively, our results support a role for midnolin in regulating cholesterol/lipid metabolism in the liver. Thus, midnolin may represent a novel therapeutic target for NAFLD. Finally, our observation that midnolin was essential for survival underscores the broad importance of this gene beyond its role in liver biology.NEW & NOTEWORTHY We have developed and now report on the first functional global midnolin knockout mouse model. We found that global heterozygous midnolin knockout attenuated the severity of nonalcoholic fatty liver disease (NAFLD) in mice fed a Western-style diet, high in fat, cholesterol, and fructose, and this attenuation in disease was associated with significantly reduced levels of large lipid droplets, hepatic free cholesterol, and serum LDL, with significantly differential gene expression involved in cholesterol/lipid metabolism.

Effect of Medically Tailored Meals on Clinical Outcomes in Recently Hospitalized High-Risk Adults.

BACKGROUND: Inability to adhere to nutritional recommendations is common and linked to worse outcomes in patients with nutrition-sensitive conditions. OBJECTIVES: The purpose of this study is to evaluate whether medically tailored meals (MTMs) improve outcomes in recently discharged adults with nutrition-sensitive conditions compared with usual care. RESEARCH DESIGN: Remote pragmatic randomized trial. SUBJECTS: Adults with heart failure, diabetes, or chronic kidney disease being discharged home between April 27, 2020, and June 9, 2021, from 5 hospitals within an integrated health care delivery system. MEASURES: Participants were prerandomized to 10 weeks of MTMs (with or without virtual nutritional counseling) compared with usual care. The primary outcome was all-cause hospitalization within 90 days after discharge. Exploratory outcomes included all-cause and cause-specific health care utilization and all-cause death within 90 days after discharge. RESULTS: A total of 1977 participants (MTMs: n=993, with 497 assigned to also receive virtual nutritional counseling; usual care: n=984) were enrolled. Compared with usual care, MTMs did not reduce all-cause hospitalization at 90 days after discharge [adjusted hazard ratio, aHR: 1.02, 95% confidence interval (CI), 0.86-1.21]. In exploratory analyses, MTMs were associated with lower mortality (aHR: 0.65, 95% CI, 0.43-0.98) and fewer hospitalizations for heart failure (aHR: 0.53, 95% CI, 0.33-0.88), but not for any emergency department visits (aHR: 0.95, 95% CI, 0.78-1.15) or diabetes-related hospitalizations (aHR: 0.75, 95% CI, 0.31-1.82). No additional benefit was observed with virtual nutritional counseling. CONCLUSIONS: Provision of MTMs after discharge did not reduce risk of all-cause hospitalization in adults with nutrition-sensitive conditions. Additional large-scale randomized controlled trials are needed to definitively determine the impact of MTMs on survival and cause-specific health care utilization in at-risk individuals.

Midnolin Regulates Liver Cancer Cell Growth In Vitro and In Vivo.

Hepatocellular carcinoma (HCC) ranks worldwide as one of the most lethal cancers. In spite of the vast existing knowledge about HCC, the pathogenesis of HCC is not completely understood. Discovery of novel genes that contribute to HCC pathogenesis will provide new insights for better understanding and treating HCC. The relatively obscure gene midnolin has been studied for over two decades; however, its biological roles are largely unknown. Our study is the first to demonstrate the functional significance of midnolin in HCC/cancer: Midnolin expression correlates with poor prognosis in HCC patients, and suppression of midnolin severely inhibits tumorigenicity of HCC cells in vitro and in mice and disrupts retinoic acid/lipid metabolism in these cells.

Thioacetamide-Induced Norepinephrine Production by Hepatocytes is Associated with Hepatic Stellate Cell Activation and Liver Fibrosis.

BACKGROUND: Collagen production by activated hepatic stellate cells (HSCs) to encapsulate injury is part of the natural wound-healing response in injured liver. However, persistent activation of HSCs can lead to pathological fibrogenesis. Such persistent HSC activation could be mediated by norepinephrine (NE), a reaction product of dopamine beta-hydroxylase (DBH). OBJECTIVE: To investigate the potential paracrine role of NE in hepatotoxin thioacetamide (TAA)-induced liver fibrosis. METHODS: In TAA-treated mice, fibrotic liver tissue showed significant increases in the mRNA expression of DBH up to 14-fold and collagen up to 7-fold. Immunohistochemical staining showed increased DBH protein expression in fibrotic liver tissue. Parenchymal hepatocyte cell line HepG2 expressed DBH and secreted NE, and the conditioned medium of HepG2 cells promoted collagenesis in nonparenchymal HSC cell line LX-2. TAA treatment increased DBH expression by 170% in HepG2 cells, as well as increased NE by 120% in the conditioned medium of HepG2 cells. The conditioned medium of TAA-treated HepG2 cells was used to culture LX-2 cells, and was found to increase collagen expression by 80% in LX-2 cells. Collagen expression was reduced by pre-treating HepG2 cells with siRNA targeting DBH or by adding NE antagonists to the conditioned medium. RESULTS: Finally, TAA-induced oxidative stress in HepG2 cells was associated with induction of DBH expression. Collectively, our results suggest a potential role for DBH/NE-mediated crosstalk between hepatocytes and HSCs in fibrogenesis. CONCLUSION: From a therapeutic standpoint, antagonism of DBH/NE induction in hepatocytes might be a useful strategy to suppress pathological fibrogenesis.

Human Immunodeficiency Virus Infection and Variation in Heart Failure Risk by Age, Sex, and Ethnicity: The HIV HEART Study.

OBJECTIVES: To evaluate the risk of heart failure (HF) linked to human immunodeficiency virus (HIV) infection, how risk varies by demographic characteristics, and whether it is explained by atherosclerotic disease or risk factor treatment. PATIENTS AND METHODS: We performed a retrospective cohort study of persons with HIV (PWHs) from January 1, 2000, through December 31, 2016, frequency-matched 1:10 to persons without HIV on year of entry, age, sex, race/ethnicity, and treating facility. We evaluated the risk of incident HF associated with HIV infection, overall and by left ventricular systolic function, and whether HF risk varied by demographic characteristics. RESULTS: Among 38,868 PWHs and 386,586 matched persons without HIV, mean ± SD age was 41.4±10.8 years, with 12.3% female, 21.1% Black, 20.5% Hispanic, and 3.9% Asian/Pacific Islander. During median follow-up of 3.8 years (interquartile range, 1.4-9.0 years), the rate (per 100 person-years) of incident HF was 0.23 in PWHs vs 0.15 in those without HIV (P<.001). The PWHs had a higher adjusted HF rate (adjusted hazard ratio [aHR], 1.73; 95% confidence interval [CI], 1.57 to 1.91), which was only modestly attenuated after accounting for interim acute coronary syndrome events. Results were similar by systolic function category. The adjusted risk of HF in PWHs was more prominent for those 40 years and younger (aHR, 2.45; 95% CI, 1.92 to 3.03), women (aHR, 2.48; 95% CI, 1.90 to 3.26), and Asian/Pacific Islanders (aHR, 2.46; 95% CI, 1.27 to 4.74). CONCLUSION: HIV infection increases the risk of HF, which varied by demographic characteristics and was not primarily mediated through atherosclerotic disease pathways or differential use of cardiopreventive medications.

Magnetic resonance imaging for characterization of hepatocellular carcinoma metabolism.

With a better understanding of the pathophysiological and metabolic changes in hepatocellular carcinoma (HCC), multiparametric and novel functional magnetic resonance (MR) and positron emission tomography (PET) techniques have received wide interest and are increasingly being applied in preclinical and clinical research. These techniques not only allow for non-invasive detection of structural, functional, and metabolic changes in malignant tumor cells but also characterize the tumor microenvironment (TME) and the interactions of malignant tumor cells with the TME, which has hypoxia and low pH, resulting from the Warburg effect and accumulation of metabolites produced by tumor cells and other cellular components. The heterogeneity and complexity of the TME require a combination of images with various parameters and modalities to characterize tumors and guide therapy. This review focuses on the value of multiparametric magnetic resonance imaging and PET/MR in evaluating the structural and functional changes of HCC and in detecting metabolites formed owing to HCC and the TME.

Differential Kat3 Usage Orchestrates the Integration of Cellular Metabolism with Differentiation.

The integration of cellular status with metabolism is critically important and the coupling of energy production and cellular function is highly evolutionarily conserved. This has been demonstrated in stem cell biology, organismal, cellular and tissue differentiation and in immune cell biology. However, a molecular mechanism delineating how cells coordinate and couple metabolism with transcription as they navigate quiescence, growth, proliferation, differentiation and migration remains in its infancy. The extreme N-termini of the Kat3 coactivator family members, CBP and p300, by far the least homologous regions with only 66% identity, interact with members of the nuclear receptor family, interferon activated Stat1 and transcriptionally competent ß-catenin, a critical component of the Wnt signaling pathway. We now wish to report based on multiomic and functional investigations, utilizing p300 knockdown, N-terminal p300 edited and p300 S89A edited cell lines and p300 S89A knockin mice, that the N-termini of the Kat3 coactivators provide a highly evolutionarily conserved hub to integrate multiple signaling cascades to coordinate cellular metabolism with the regulation of cellular status and function.

Pharmacologically Targeting the WNT/ß-Catenin Signaling Cascade: Avoiding the Sword of Damocles.

WNT/ß-catenin signaling plays fundamental roles in numerous developmental processes and in adult tissue homeostasis and repair after injury, by controlling cellular self-renewal, activation, division, differentiation, movement, genetic stability, and apoptosis. As such, it comes as no surprise that dysregulation of WNT/ß-catenin signaling is associated with various diseases, including cancer, fibrosis, neurodegeneration, etc. Although multiple agents that specifically target the WNT/ß-catenin signaling pathway have been studied preclinically and a number have entered clinical trials, none has been approved by the FDA to date. In this chapter, we provide our insights as to the reason(s) it has been so difficult to safely pharmacologically target the WNT/ß-catenin signaling pathway and discuss the significant efforts undertaken towards this goal.

p300 Serine 89: A Critical Signaling Integrator and Its Effects on Intestinal Homeostasis and Repair.

Differential usage of Kat3 coactivators, CBP and p300, by ß-catenin is a fundamental regulatory mechanism in stem cell maintenance and initiation of differentiation and repair. Based upon our earlier pharmacologic studies, p300 serine 89 (S89) is critical for controlling differential coactivator usage by ß-catenin via post-translational phosphorylation in stem/progenitor populations, and appears to be a target for a number of kinase cascades. To further investigate mechanisms of signal integration effected by this domain, we generated p300 S89A knock-in mice. We show that S89A mice are extremely sensitive to intestinal insult resulting in colitis, which is known to significantly increase the risk of developing colorectal cancer. We demonstrate cell intrinsic differences, and microbiome compositional differences and differential immune responses, in intestine of S89A versus wild type mice. Genomic and proteomic analyses reveal pathway differences, including lipid metabolism, oxidative stress response, mitochondrial function and oxidative phosphorylation. The diverse effects on fundamental processes including epithelial differentiation, metabolism, immune response and microbiome colonization, all brought about by a single amino acid modification S89A, highlights the critical role of this region in p300 as a signaling nexus and the rationale for conservation of this residue and surrounding region for hundreds of million years of vertebrate evolution.

Does instillation of lidocaine gel following flexible cystoscopy decrease the severity of post procedure symptoms? A randomised controlled trial assessing the efficacy of lidocaine gel post flexible cystoscopy.

OBJECTIVE: To assess whether instillation of lidocaine gel both before and after flexible cystoscopy is more effective at reducing post procedural symptoms than instillation of lidocaine gel pre flexible cystoscopy alone. We hypothesise that inadequate urethral dwell time and dilution of lidocaine gel by the irrigation fluid during flexible cystoscopy limits its anaesthetic efficacy. Only one other study has attempted to reduce bothersome urinary symptoms through an intervention after flexible cystoscopy. METHODS: This was a randomised controlled trial in which patients were randomised 1:1 to receive lidocaine gel pre and post flexible cystoscopy (treatment) or lidocaine gel pre flexible cystoscopy only (control). Patient-reported outcome measures were used to assess symptoms and quality of life prior to cystoscopy, on day 2 and day 7 post cystoscopy. RESULT: Fifty patients were divided equally between the treatment and control groups. There were no significant differences in baseline characteristics between the groups (p = 1.000). An overall symptoms variable was measured, though no significant difference was found in the distribution of responses between the groups at baseline, 2 or 7 days after the flexible cystoscopy (p = 0.423, 0.651,0.735). In the treatment group, 1 patient (4.0%) presented to a doctor for review following flexible cystoscopy, and 4 patients (16.0%) presented in the control group (p = 0.349). CONCLUSION: Initial study results suggest that post-operative lidocaine does not significantly limit the exacerbation of urinary symptoms following flexible cystoscopy; however, our results are not powered to detect a small difference. We do not recommend a change in practice based on our results.

Human immunodeficiency virus infection and risks of morbidity and death in adults with incident heart failure.

Aims: Human immunodeficiency virus (HIV) increases the risk of heart failure (HF), but whether it influences subsequent morbidity and mortality remains unclear. Methods and results: We investigated the risks of hospitalization for HF, HF-related emergency department (ED) visits, and all-cause death in an observational cohort of incident HF patients with and without HIV using data from three large US integrated healthcare delivery systems. We estimated incidence rates and adjusted hazard ratios (aHRs) by HIV status at the time of HF diagnosis for subsequent outcomes. We identified 448 persons living with HIV (PLWH) and 3429 without HIV who developed HF from a frequency-matched source cohort of 38 868 PLWH and 386 586 without HIV. Mean age was 59.5 ± 11.3 years with 9.8% women and 31.8% Black, 13.1% Hispanic, and 2.2% Asian/Pacific Islander. Compared with persons without HIV, PLWH had similar adjusted rates of HF hospitalization [aHR 1.01, 95% confidence interval (CI): 0.81-1.26] and of HF-related ED visits [aHR 1.22 (95% CI: 0.99-1.50)], but higher adjusted rates of all-cause death [aHR 1.31 (95% CI: 1.08-1.58)]. Adjusted rates of HF-related morbidity and all-cause death were directionally consistent across a wide range of CD4 counts but most pronounced in the subset with a baseline CD4 count <200 or 200-499 cells/µL. Conclusion: In a large, diverse cohort of adults with incident HF receiving care within integrated healthcare delivery systems, PLWH were at an independently higher risk of all-cause death but not HF hospitalizations or HF-related ED visits. Future studies investigating modifiable HIV-specific risk factors may facilitate more personalized care to optimize outcomes for PLWH and HF.

The influence of acute exercise on bone biomarkers: protocol for a systematic review with meta-analysis.

BACKGROUND: Bone is a plastic tissue that is responsive to its physical environment. As a result, exercise interventions represent a potential means to influence the bone. However, little is currently known about how various exercise and participant characteristics interact to influence bone metabolism. Acute, controlled, interventions provide an in vivo model through which the acute bone response to exercise can be investigated, typically by monitoring circulating bone biomarkers. Currently, substantial heterogeneity in factors such as study design, quality, exercise, and participant characteristics render it difficult to synthesize and evaluate the available evidence. Using a systematic review and meta-analytic approach, the aim of this investigation is to quantify the effect of an acute exercise bout on circulating bone biomarkers as well as examine the potential factors that may moderate this response, e.g., variation in participant, exercise, and sampling characteristics. METHODS: This protocol was designed in accordance with the PRISMA-P guidelines. Seven databases (MEDLINE, Embase, Sport Discus, Cochrane CENTRAL, PEDro, LILACS, and Ibec) will be systematically searched and supplemented by a secondary screening of the reference lists of all included articles. The PICOS (Population, Intervention, Comparator, Outcomes and Study Design) approach was used to guide the determination of the eligibility criteria. Participants of any age, sex, training, or health status will be considered for inclusion. We will select studies that have measured the bone biomarker response before and after an acute exercise session. All biomarkers considered to represent the bone metabolism will be considered for inclusion, and sensitivity analyses will be conducted using reference biomarkers for the measurement of bone resorption and formation (namely ß-CTX-1 and P1NP). Multi-level, meta-regression models within a Bayesian framework will be used to explore the main effect of acute exercise on bone biomarkers as well as potential moderating factors. The risk of bias for each individual study will be evaluated using a modified version of the Downs and Black checklist while certainty in resultant outcomes will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. DISCUSSION: A better understanding of the bone metabolic response to an acute bout of exercise has the potential to advance our understanding of the mechanisms through which this stimulus impacts bone metabolism, including factors that may moderate this response. Additionally, we will identify current gaps in the evidence base and provide recommendations to inform future research. SYSTEMATIC REVIEW REGISTRATION: This protocol was prospectively registered in the Open Science Framework Registry ( https://osf.io/6f8dz ).

The Heart Failure Readmission Intervention by Variable Early Follow-up (THRIVE) Study: A Pragmatic Randomized Trial.

BACKGROUND: In-person clinic follow-up within 7 days after discharge from a heart failure hospitalization is associated with lower 30-day readmission. However, health systems and patients may find it difficult to complete an early postdischarge clinic visit, especially during the current pandemic. We evaluated the effect on 30-day readmission and death of follow-up within 7 days postdischarge guided by an initial structured nonphysician telephone visit compared with follow-up guided by an initial clinic visit with a physician. METHODS AND RESULTS: We conducted a pragmatic randomized trial in a large integrated healthcare delivery system. Adults being discharged home after hospitalization for heart failure were randomly assigned to either an initial telephone visit with a nurse or pharmacist to guide follow-up or an initial in-person clinic appointment with primary care physicians providing usual care within the first 7 days postdischarge. Telephone appointments included a structured protocol enabling medication titration, laboratory ordering, and booking urgent clinic visits as needed under physician supervision. Outcomes included 30-day readmissions and death and frequency and type of completed follow-up within 7 days of discharge. Among 2091 participants (mean age 78 years, 44% women), there were no significant differences in 30-day heart failure readmission (8.6% telephone, 10.6% clinic, P=0.11), all-cause readmission (18.8% telephone, 20.6% clinic, P=0.30), and all-cause death (4.0% telephone, 4.6% clinic, P=0.49). Completed 7-day follow-up was higher in 1027 patients randomized to telephone follow-up (92%) compared with 1064 patients assigned to physician clinic follow-up (79%, P<0.001). Overall frequency of clinic visits during the first 7 days postdischarge was lower in participants assigned to nonphysician telephone guided follow-up (48%) compared with physician clinic-guided follow-up (77%, P<0.001). CONCLUSIONS: Early, structured telephone follow-up after hospitalization for heart failure can increase 7-day follow-up and reduce in-person visits with comparable 30-day clinical outcomes within an integrated care delivery framework. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03524534.

Targeting the CBP/ß-Catenin Interaction to Suppress Activation of Cancer-Promoting Pancreatic Stellate Cells.

BACKGROUND: Although cyclic AMP-response element binding protein-binding protein (CBP)/ß-catenin signaling is known to promote proliferation and fibrosis in various organ systems, its role in the activation of pancreatic stellate cells (PSCs), the key effector cells of desmoplasia in pancreatic cancer and fibrosis in chronic pancreatitis, is largely unknown. METHODS: To investigate the role of the CBP/ß-catenin signaling pathway in the activation of PSCs, we have treated mouse and human PSCs with the small molecule specific CBP/ß-catenin antagonist ICG-001 and examined the effects of treatment on parameters of activation. RESULTS: We report for the first time that CBP/ß-catenin antagonism suppresses activation of PSCs as evidenced by their decreased proliferation, down-regulation of "activation" markers, e.g., α-smooth muscle actin (α-SMA/Acta2), collagen type I alpha 1 (Col1a1), Prolyl 4-hydroxylase, and Survivin, up-regulation of peroxisome proliferator activated receptor gamma (Ppar-γ) which is associated with quiescence, and reduced migration; additionally, CBP/ß-catenin antagonism also suppresses PSC-induced migration of cancer cells. CONCLUSION: CBP/ß-catenin antagonism represents a novel therapeutic strategy for suppressing PSC activation and may be effective at countering PSC promotion of pancreatic cancer.

HBV X protein mutations affect HBV transcription and association of histone-modifying enzymes with covalently closed circular DNA.

The hepatitis B X protein (HBx) plays a role in the epigenetic regulation of hepatitis B virus (HBV) replication. This study investigated the effects of HBx mutations on HBV transcription and the recruitment of HBx, histone acetyl-transferase P300 and histone deacetylase 1 (HDAC1) to circularized HBV DNA (which resembles covalently closed circular DNA [cccDNA]). Compared with wild type, majority of mutants had lower levels of intracellular HBV RNA (44-77% reduction) and secretory HBsAg (25-81% reduction), and 12 mutants had a reduction in intracellular encapsidated HBV DNA (33-64% reduction). Eight mutants with >70% reduction in HBV RNA and/or HBsAg were selected for chromatin immunoprecipitation analysis. Four HBx mutants with mutations in amino acid residues 55-60 and 121-126 had a lower degree of HBx-cccDNA association than wild type HBx (mean % input: 0.02-0.64% vs. 3.08% in wild type). A reduced association between cccDNA and P300 (mean % input: 0.69-1.81% vs. 3.48% in wild type) and an augmented association with HDAC1 (mean % input: 4.01-14.0% vs. 1.53% in wild type) were detected. HBx amino acid residues 55-60 and 121-126 may play an important role in HBV transcription regulation, via their impeded interaction with cccDNA and altered recruitment of histone modifying enzymes to cccDNA.

Targeted genomic profiling identifies frequent deleterious mutations in FAT4 and TP53 genes in HBV-associated hepatocellular carcinoma.

BACKGROUND: Hepatitis B virus (HBV) is the major risk factor for hepatocellular carcinoma (HCC). The molecular mechanisms underlying HBV-associated HCC pathogenesis is still unclear. Genetic alterations in cancer-related genes have been linked to many human cancers. Here, we aimed to explore genetic alterations in selected cancer-related genes in patients with HBV-associated HCC. METHODS: Targeted sequencing was used to analyze six cancer-related genes (PIK3CA, TP53, FAT4, IRF2, HNF4α and ARID1A) in eight pairs of HBV-associated HCC tumors and their adjacent non-tumor tissues. Sanger sequencing, quantitative PCR, Western-blotting and RNAi-mediated gene knockdown were used to further validate findings. RESULTS: Targeted sequencing revealed thirteen non-synonymous mutations, of which 9 (69%) were found in FAT4 and 4 (31%) were found in TP53 genes. Non-synonymous mutations were not found in PIK3CA, IRF2, HNF4α and ARID1A. Among these 13 non-synonymous mutations, 12 (8 in FAT4 and 4 in TP53) were predicted to have deleterious effect on protein function by in silico analysis. For TP53, Y220S, R249S and P250R non-synonymous mutations were solely identified in tumor tissues. Further expression profiling of FAT4 and TP53 on twenty-eight pairs of HCC tumor and non-tumor tissues confirmed significant downregulation of both genes in HCC tumors compared with their non-tumor counterparts (P < 0.001 and P < 0.01, respectively). Functional analysis using RNAi-mediated knockdown of FAT4 revealed an increased cancer cell growth and proliferation, suggesting the putative tumor suppressor role of FAT4 in HCC. CONCLUSIONS: This study highlights the importance of FAT4 and TP53 in HCC pathogenesis and identifies new genetic variants that may have potentials for development of precise therapy for HCC.

The Mode of Stem Cell Division Is Dependent on the Differential Interaction of ß-Catenin with the Kat3 Coactivators CBP or p300.

Normal long-term repopulating somatic stem cells (SSCs) preferentially divide asymmetrically, with one daughter cell remaining in the niche and the other going on to be a transient amplifying cell required for generating new tissue in homeostatic maintenance and repair processes, whereas cancer stem cells (CSCs) favor symmetric divisions. We have previously proposed that differential ß-catenin modulation of transcriptional activity via selective interaction with either the Kat3 coactivator CBP or its closely related paralog p300, regulates symmetric versus asymmetric division in SSCs and CSCs. We have previously demonstrated that SSCs that divide asymmetrically per force retain one of the dividing daughter cells in the stem cell niche, even when treated with specific CBP/ß-catenin antagonists, whereas CSCs can be removed from their niche via forced stochastic symmetric differentiative divisions. We now demonstrate that loss of p73 in early corticogenesis biases ß-catenin Kat3 coactivator usage and enhances ß-catenin/CBP transcription at the expense of ß-catenin/p300 transcription. Biased ß-catenin coactivator usage has dramatic consequences on the mode of division of neural stem cells (NSCs), but not neurogenic progenitors. The observed increase in symmetric divisions due to enhanced ß-catenin/CBP interaction and transcription leads to an immediate increase in NSC symmetric differentiative divisions. Moreover, we demonstrate for the first time that the complex phenotype caused by the loss of p73 can be rescued in utero by treatment with the small-molecule-specific CBP/ß-catenin antagonist ICG-001. Taken together, our results demonstrate the causal relationship between the choice of ß-catenin Kat3 coactivator and the mode of stem cell division.