Mortality Risk Assessment Using the REVEAL 2.0 Score in Pulmonary Hypertension Secondary to Left Heart Disease.

Background: Pulmonary hypertension (PH) frequently complicates the course of patients with left heart disease (PH-LHD) and is associated with worse clinical outcomes. Mortality calculators for PH-LHD are lacking, and it is unclear whether any risk prediction tools originally derived from other forms of PH can accurately predict outcomes in patients with PH-LHD. Methods: We retrospectively analyzed data from 161 patients diagnosed with PH-LHD referred to our pulmonary hypertension center from 2016 to 2022. We calculated the Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL 2.0) risk score and categorized patients as low, intermediate, or high-risk. We assessed survival at 1 and 3 years using Kaplan-Meier and Cox proportional hazards, as well as classification performance using a concordance index. Results: At the first outpatient visit, 15% of patients were stratified as low-risk, 27% as intermediate, and 57% as high-risk. Cumulative 1-year survival rates were 100%, 94%, and 91% for the low, intermediate, and high-risk strata, respectively. Cumulative 3-year survival rates were 96%, 89%, and 70% for the low, intermediate, and high-risk strata, respectively. We found no difference in outcomes at 1 year between risk groups. High-risk patients had an increased risk of death at 3 years using REVEAL 2.0 (HR 5.32, p < 0.001). However, while REVEAL 2.0 accurately discriminated high-risk patients, the hazard ratio was not statistically different between patients classified as intermediate-risk compared to low-risk. Conclusion: REVEAL 2.0 accurately predicted 3-year survival in PH-LHD patients with high-risk features. However, the mortality risk between patients classified as intermediate-risk was not different from the low-risk stratum, suggesting inaccurate classification for this group of patients.

FOXF1 promotes tumor vessel normalization and prevents lung cancer progression through FZD4.

Cancer cells re-program normal lung endothelial cells (EC) into tumor-associated endothelial cells (TEC) that form leaky vessels supporting carcinogenesis. Transcriptional regulators that control the reprogramming of EC into TEC are poorly understood. We identified Forkhead box F1 (FOXF1) as a critical regulator of EC-to-TEC transition. FOXF1 was highly expressed in normal lung vasculature but was decreased in TEC within non-small cell lung cancers (NSCLC). Low FOXF1 correlated with poor overall survival of NSCLC patients. In mice, endothelial-specific deletion of FOXF1 decreased pericyte coverage, increased vessel permeability and hypoxia, and promoted lung tumor growth and metastasis. Endothelial-specific overexpression of FOXF1 normalized tumor vessels and inhibited the progression of lung cancer. FOXF1 deficiency decreased Wnt/ß-catenin signaling in TECs through direct transcriptional activation of Fzd4. Restoring FZD4 expression in FOXF1-deficient TECs through endothelial-specific nanoparticle delivery of Fzd4 cDNA rescued Wnt/ß-catenin signaling in TECs, normalized tumor vessels and inhibited the progression of lung cancer. Altogether, FOXF1 increases tumor vessel stability, and inhibits lung cancer progression by stimulating FZD4/Wnt/ß-catenin signaling in TECs. Nanoparticle delivery of FZD4 cDNA has promise for future therapies in NSCLC.

Corrigendum: Improving anti-tumor efficacy of low-dose Vincristine in rhabdomyosarcoma via the combination therapy with FOXM1 inhibitor RCM1.

[This corrects the article DOI: 10.3389/fonc.2023.1112859.].

Demonstration of Safety in Wild Type Mice of npFOXF1, a Novel Nanoparticle-Based Gene Therapy for Alveolar Capillary Dysplasia with Misaligned Pulmonary Veins.

Introduction: Alveolar Capillary Dysplasia with Misaligned Pulmonary Veins (ACDMPV) is a fatal congenital disease resulting from a pulmonary vascular endothelial deficiency of FOXF1, producing abnormal morphogenesis of alveolar capillaries, malpositioned pulmonary veins and disordered development of lung lobes. Affected neonates suffer from cyanosis, severe breathing insufficiency, pulmonary hypertension, and death typically within days to weeks after birth. Currently, no treatment exists for ACDMPV, although recent murine research in the Kalinichenko lab demonstrates nanoparticle delivery improves survival and reconstitutes normal alveolar-capillary architecture. The aim of the present study is to investigate the safety of intravenous administration of FOXF1-expressing PEI-PEG nanoparticles (npFOXF1), our pioneering treatment for ACDMPV. Methods: npFOXF1 was constructed, validated, and subsequently administered in a single dose to postnatal day 14 (P14) mice via retro-orbital injection. Biochemical, serologic, and histologic safety were monitored at postnatal day 16 (P16) and postnatal day 21 (P21). Results: With treatment we observed no lethality, and the general condition of mice revealed no obvious abnormalities. Serum chemistry, whole blood, and histologic toxicity was assayed on P16 and P21 and revealed no abnormality. Discussion: In conclusion, npFOXF1 has a very good safety profile and combined with preceding studies showing therapeutic efficacy, npFOXF1 can be considered as a good candidate therapy for ACDMPV in human neonates.

Improving anti-tumor efficacy of low-dose Vincristine in rhabdomyosarcoma via the combination therapy with FOXM1 inhibitor RCM1.

Rhabdomyosarcoma (RMS) is a highly metastatic soft-tissue sarcoma that often develops resistance to current therapies, including vincristine. Since the existing treatments have not significantly improved survival, there is a critical need for new therapeutic approaches for RMS patients. FOXM1, a known oncogene, is highly expressed in RMS, and is associated with the worst prognosis in RMS patients. In the present study, we found that the combination treatment with specific FOXM1 inhibitor RCM1 and low doses of vincristine is more effective in increasing apoptosis and decreasing RMS cell proliferation in vitro compared to single drugs alone. Since RCM1 is highly hydrophobic, we developed innovative nanoparticle delivery system containing poly-beta-amino-esters and folic acid (NPFA), which efficiently delivers RCM1 to mouse RMS tumors in vivo. The combination of low doses of vincristine together with intravenous administration of NPFA nanoparticles containing RCM1 effectively reduced RMS tumor volumes, increased tumor cell death and decreased tumor cell proliferation in RMS tumors compared to RCM1 or vincristine alone. The combination therapy was non-toxic as demonstrated by liver metabolic panels using peripheral blood serum. Using RNA-seq of dissected RMS tumors, we identified Chac1 as a uniquely downregulated gene after the combination treatment. Knockdown of Chac1 in RMS cells in vitro recapitulated the effects of the combination therapy. Altogether, combination treatment with low doses of vincristine and nanoparticle delivery of FOXM1 inhibitor RCM1 in a pre-clinical model of RMS has superior anti-tumor effects and decreases CHAC1 while reducing vincristine toxicity.

Hypoxia represses FOXF1 in lung endothelial cells through HIF-1α.

Introduction: Forkhead Box F1 (FOXF1) transcription factor plays a critical role in lung angiogenesis during embryonic development and lung repair after injury. FOXF1 expression is decreased in endothelial cells after lung injury; however, molecular mechanisms responsible for the FOXF1 transcript changes in injured lung endothelium remain unknown. Methods: We used immunostaining of injured mouse lung tissues, FACS-sorted lung endothelial cells from hypoxia-treated mice, and data from patients diagnosed with hypoxemic respiratory failure to demonstrate that hypoxia is associated with decreased FOXF1 expression. Endothelial cell cultures were used to induce hypoxia in vitro and identify the upstream molecular mechanism through which hypoxia inhibits FOXF1 gene expression. Results: Bleomycin-induced lung injury induced hypoxia in the mouse lung tissue which was associated with decreased Foxf1 expression. Human FOXF1 mRNA was decreased in the lungs of patients diagnosed with hypoxemic respiratory failure. Mice exposed to hypoxia exhibited reduced Foxf1 expression in the lung tissue and FACS-sorted lung endothelial cells. In vitro, hypoxia (1% of O2) or treatment with cobalt (II) chloride increased HIF-1α protein levels but inhibited FOXF1 expression in three endothelial cell lines. Overexpression of HIF-1α in cultured endothelial cells was sufficient to inhibit Foxf1 expression. siRNA-mediated depletion of HIF-1α prevented the downregulation of Foxf1 gene expression after hypoxia or cobalt (II) chloride treatment. Conclusion: Hypoxia inhibits FOXF1 expression in endothelial cells in a HIF-1α dependent manner. Our data suggest that endothelial cell-specific inhibition of HIF-1α via gene therapy can be considered to restore FOXF1 and improve lung repair in patients with severe lung injury.

Distinct Platelet Ribonucleic Acid Signatures in Patients with Pulmonary Hypertension.

Rationale: Pulmonary hypertension encompasses progressive disorders leading to right ventricular dysfunction and early death. Late detection is an important cause of poor clinical outcomes. However, biomarkers that accurately predict the presence of pulmonary hypertension are currently lacking. Objectives: In this study, we provide evidence that blood platelets contain a distinctive ribonucleic acid (RNA) profile that may be exploited for the detection of pulmonary hypertension. Methods: Blood platelet RNA was isolated prospectively from 177 prevalent patients with different subtypes of pulmonary hypertension as well as 195 control subjects clinically not suspected of pulmonary hypertension. Sequencing libraries were created using SMARTer (Switching Mechanism at 5' end of RNA Template) copy desoxyribonucleic acid amplification and sequenced on the Illumina High Throughput Sequencing platform. RNA-sequencing reads were mapped to the human reference genome, and intron-spanning spliced RNA reads were selected. Differential spliced RNA panels were calculated by analysis of variance statistics. A particle swarm optimization-enhanced classification algorithm was built employing a development (n = 213 samples) and independent validation series (n = 159 samples). Results: We detected a total of 4,014 different RNAs in blood platelets from patients with pulmonary hypertension (n = 177) and asymptomatic control subjects (n = 195). Gene ontology analysis revealed enhanced RNA concentrations for genes related to RNA processing, translation, and mitochondrial function. A particle swarm optimization-selected RNA panel of 408 distinctive differentially spliced RNAs mediated detection of pulmonary hypertension with 93% sensitivity, 62% specificity, 77% accuracy, 0.89 (95% confidence interval, 0.83-0.93) area under the curve, and a negative predictive value of 91% in the independent validation series. The prediction score was independent of age, sex, smoking, pulmonary hypertension subtype, and the use of pulmonary hypertension-specific medication or anticoagulants. Conclusions: A platelet RNA panel may accurately discriminate patients with pulmonary hypertension from asymptomatic control subjects. In the light of current diagnostic delays, this study is the starting point for further development and evaluation of a platelet RNA-based blood test to ultimately improve early diagnosis and clinical outcomes in patients with pulmonary hypertension.

Nanoparticle Delivery of STAT3 Alleviates Pulmonary Hypertension in a Mouse Model of Alveolar Capillary Dysplasia.

BACKGROUND: Pulmonary hypertension (PH) is a common complication in patients with alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV), a severe congenital disorder associated with mutations in the FOXF1 gene. Although the loss of alveolar microvasculature causes PH in patients with ACDMPV, it is unknown whether increasing neonatal lung angiogenesis could prevent PH and right ventricular (RV) hypertrophy. METHODS: We used echocardiography, RV catheterization, immunostaining, and biochemical methods to examine lung and heart remodeling and RV output in Foxf1WT/S52F mice carrying the S52F Foxf1 mutation (identified in patients with ACDMPV). The ability of Foxf1WT/S52F mutant embryonic stem cells to differentiate into respiratory cell lineages in vivo was examined using blastocyst complementation. Intravascular delivery of nanoparticles with a nonintegrating Stat3 expression vector was used to improve neonatal pulmonary angiogenesis in Foxf1WT/S52F mice and determine its effects on PH and RV hypertrophy. RESULTS: Foxf1WT/S52F mice developed PH and RV hypertrophy after birth. The severity of PH in Foxf1WT/S52F mice directly correlated with mortality, low body weight, pulmonary artery muscularization, and increased collagen deposition in the lung tissue. Increased fibrotic remodeling was found in human ACDMPV lungs. Mouse embryonic stem cells carrying the S52F Foxf1 mutation were used to produce chimeras through blastocyst complementation and to demonstrate that Foxf1WT/S52F embryonic stem cells have a propensity to differentiate into pulmonary myofibroblasts. Intravascular delivery of nanoparticles carrying Stat3 cDNA protected Foxf1WT/S52F mice from RV hypertrophy and PH, improved survival, and decreased fibrotic lung remodeling. CONCLUSIONS: Nanoparticle therapies increasing neonatal pulmonary angiogenesis may be considered to prevent PH in ACDMPV.

Resistin-Like Molecule α Dysregulates Cardiac Bioenergetics in Neonatal Rat Cardiomyocytes.

Heart (right) failure is the most frequent cause of death in patients with pulmonary arterial hypertension. Although historically, increased right ventricular afterload has been considered the main contributor to right heart failure in such patients, recent evidence has suggested a potential role of load-independent factors. Here, we tested the hypothesis that resistin-like molecule α (RELMα), which has been implicated in the pathogenesis of vascular remodeling in pulmonary artery hypertension, also contributes to cardiac metabolic remodeling, leading to heart failure. Recombinant RELMα (rRELMα) was generated via a Tet-On expression system in the T-REx 293 cell line. Cultured neonatal rat cardiomyocytes were treated with purified rRELMα for 24 h at a dose of 50 nM. Treated cardiomyocytes exhibited decreased mRNA and protein expression of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) and transcription factors PPARα and ERRα, which regulate mitochondrial fatty acid metabolism, whereas genes that encode for glycolysis-related proteins were significantly upregulated. Cardiomyocytes treated with rRELMα also exhibited a decreased basal respiration, maximal respiration, spare respiratory capacity, ATP-linked OCR, and increased glycolysis, as assessed with a microplate-based cellular respirometry apparatus. Transmission electron microscopy revealed abnormal mitochondrial ultrastructure in cardiomyocytes treated with rRELMα. Our data indicate that RELMα affects cardiac energy metabolism and mitochondrial structure, biogenesis, and function by downregulating the expression of the PGC-1α/PPARα/ERRα axis.

Angiotensin converting enzyme 2 and angiotensin (1-7) axis in pulmonary arterial hypertension.

BACKGROUND: In animal models of pulmonary arterial hypertension (PAH), angiotensin-converting enzyme (ACE)2 and angiotensin (Ang)-(1-7) have been shown to have vasodilatory, antiproliferative, antifibrotic and antihypertrophic properties. However, the status and role of the ACE2-Ang(1-7) axis in human PAH is incompletely understood. METHODS: We studied 85 patients with a diagnosis of PAH of distinct aetiologies. 55 healthy blood donors paired for age and sex served as controls. Blood samples were obtained from the pulmonary artery in patients with PAH during right heart catheterisation. Peripheral blood was obtained for both groups. Ang(1-7) and -II were measured using zone capillary electrophoresis. Aldosterone, Ang(1-9), AngA and ACE2 were measured using ELISA, and ACE2 activity was determined enzymatically. RESULTS: Of the 85 patients, 47 had idiopathic PAH, 25 had PAH associated with congenital heart disease and 13 had PAH associated with collagen vascular disease. Compared to controls, patients with PAH had a higher concentration of AngII (median 1.03, interquartile range 0.72-1.88 pmol·mL-1 versus 0.19, 0.10-0.37 pmol·mL-1; p<0.001) and of aldosterone (88.7, 58.7-132 ng·dL-1 versus 12.9, 9.55-19.9 ng·dL-1; p<0.001). Conversely, PAH patients had a lower concentration of Ang(1-7) than controls (0.69, 0.474-0.91 pmol·mL-1 versus 4.07, 2.82-6.73 pmol·mL-1; p<0.001), and a lower concentration of Ang(1-9) and AngA. Similarly, the ACE2 concentration was higher than in controls (8.7, 5.35-13.2 ng·mL-1 versus 4.53, 1.47-14.3 ng·mL-1; p=0.011), whereas the ACE2 activity was significantly reduced (1.88, 1.08-2.81 nmol·mL-1 versus 5.97, 3.1-17.8 nmol·mL-1; p<0.001). No significant differences were found among the three different aetiological forms of PAH. CONCLUSIONS: The AngII-ACE2-Ang(1-7) axis appears to be altered in human PAH and we propose that this imbalance, in favour of AngII, plays a role in the pathogenesis of the severe PAH. Further mechanistic studies are warranted.

HIMF (Hypoxia-Induced Mitogenic Factor) Signaling Mediates the HMGB1 (High Mobility Group Box 1)-Dependent Endothelial and Smooth Muscle Cell Crosstalk in Pulmonary Hypertension.

OBJECTIVE: HIMF (hypoxia-induced mitogenic factor; also known as FIZZ1 [found in inflammatory zone-1] or RELM [resistin-like molecule-α]) is an etiological factor of pulmonary hypertension (PH) in rodents, but its underlying mechanism is unclear. We investigated the immunomodulatory properties of HIMF signaling in PH pathogenesis. Approach and Results: Gene-modified mice that lacked HIMF (KO [knockout]) or overexpressed HIMF human homolog resistin (hResistin) were used for in vivo experiments. The pro-PH role of HIMF was verified in HIMF-KO mice exposed to chronic hypoxia or sugen/hypoxia. Mechanistically, HIMF/hResistin activation triggered the HMGB1 (high mobility group box 1) pathway and RAGE (receptor for advanced glycation end products) in pulmonary endothelial cells (ECs) of hypoxic mouse lungs in vivo and in human pulmonary microvascular ECs in vitro. Treatment with conditioned medium from hResistin-stimulated human pulmonary microvascular ECs induced an autophagic response, BMPR2 (bone morphogenetic protein receptor 2) defects, and subsequent apoptosis-resistant proliferation in human pulmonary artery (vascular) smooth muscle cells in an HMGB1-dependent manner. These effects were confirmed in ECs and smooth muscle cells isolated from pulmonary arteries of patients with idiopathic PH. HIMF/HMGB1/RAGE-mediated autophagy and BMPR2 impairment were also observed in pulmonary artery (vascular) smooth muscle cells of hypoxic mice, effects perhaps related to FoxO1 (forkhead box O1) dampening by HIMF. Experiments in EC-specific hResistin-overexpressing transgenic mice confirmed that EC-derived HMGB1 mediated the hResistin-driven pulmonary vascular remodeling and PH. CONCLUSIONS: In HIMF-induced PH, HMGB1-RAGE signaling is pivotal for mediating EC-smooth muscle cell crosstalk. The humanized mouse data further support clinical implications for the HIMF/HMGB1 signaling axis and indicate that hResistin and its downstream pathway may constitute targets for the development of novel anti-PH therapeutics in humans.

Consequences of chronic frequent premature atrial contractions: Association with cardiac arrhythmias and cardiac structural changes.

INTRODUCTION: Frequent premature ventricular contractions (PVCs) can cause cardiomyopathy (CM). Postextrasystolic potentiation (PESP) and irregularity have been in implicated as triggers of PVC-CM. Because both phenomena can also be found in premature atrial contractions (PACs), it is speculated that frequent PACs have similar consequences. METHODS AND RESULTS: A single-center, retrospective study included all consecutive patients undergoing a 14-day Holter monitors (November 2014 to October 2016). Patients were divided into four groups by ectopy burden group 1 (<1%) and remaining by tertiles (group 2-4). Echocardiographic and arrhythmic data were compared between PAC and PVC burdens. In addition, a translational PAC animal model was used to assess the chronic effects of frequent PACs. A total 846 patients were reviewed. In contrast to PVCs, we found no difference in left ventricular ejection fraction (LVEF), end-systolic and end-diastolic dimensions and presence of CM (LVEF <50%) between different PAC groups. Multivariate regression analysis demonstrated that only PVC burden predicted low EF (odds ratio, 1.1; confidence interval, 1.03-1.13; P = .001). While there was a weak correlation between PAC burden and supraventricular tachycardia (SVT) episodes and atrial fibrillation (AF) burden (r = 0.19; P < .001), there was no correlation between PAC burden and LVEF or CM. Finally, atrial bigeminy in our animal model did not significantly decrease LVEF after 3 months. CONCLUSION: PAC burden is associated with increased AF and SVT episodes. In contrast to a high PVC burden, a high PAC burden is not associated with CM. Our findings suggest that heart rate irregularity and/or PESP may play a minimal role in the pathophysiology of PVC-CM.

Role of the Aryl Hydrocarbon Receptor/ARNT/Cytochrome P450 System in Pulmonary Vascular Diseases.

RATIONALE: CYPs (cytochrome p450) are critically involved in the metabolism of xenobiotics and toxins. Given that pulmonary hypertension is strongly associated with environmental exposure, we hypothesize that CYPs play a role in the development and maintenance of pathological vascular remodeling. OBJECTIVE: We sought to identify key CYPs that could link drug or hormone metabolism to the development of pulmonary hypertension. METHODS AND RESULTS: We searched in Medline (PubMed) database, as well as http://www.clinicaltrials.gov, for CYPs associated with many key aspects of pulmonary arterial hypertension including, but not limited to, severe pulmonary hypertension, estrogen metabolism, inflammation mechanisms, quasi-malignant cell growth, drug susceptibility, and metabolism of the pulmonary arterial hypertension-specific drugs. CONCLUSIONS: We postulate a hypothesis where the AhR (aryl hydrocarbon receptor) mediates aberrant cell growth via expression of different CYPs associated with estrogen metabolism and inflammation.

Derivation and validation of a simple inflammation-based risk score system for predicting in-hospital mortality in acute coronary syndrome patients.

BACKGROUND: Accurate assessment of inflammatory status of patients during acute coronary syndrome (ACS) has become of great importance in their risk classification and in the research of new anti-inflammatory therapies. METHOD: The study cohort included 7396 patients with ACS. We sought to derive and internally validate an inflammation-based score that included high-sensitivity C-reactive protein, white blood cell count, and serum albumin level at admission to evaluate the predictive role of systemic inflammation in the clinical outcome of these patients. We randomly assigned patients into derivation (66.6%) and validation (33.4%) cohorts. A total of four categories of systemic inflammation were defined. RESULTS: Assessed individually, the three biomarkers were associated with a higher rate of in-hospital mortality. When we combined them into an inflammation score, in-hospital mortality was significantly different across the four categories of inflammation in the derivation cohort (1.8%, 2.8%, 4.1%, and 13.8% for without, mild, moderate, and severe inflammation, respectively; p<0.0001, C-statistic, 0.71). These results were similar in the validation cohort (1.1%, 2.9%, 5.2%, and 12.6%, respectively; p<0.0001, C-statistic, 0.71). After multivariate adjustment, only the category of severe systemic inflammation was associated with a threefold increased risk of in-hospital mortality (odds ratios 3.02, p<0.0001) and was the most powerful predictor of mortality. In the whole cohort, after subsetting patients based on GRACE risk score, the severe inflammation category was associated with a significant increase of in-hospital mortality across all sub-groups, mainly in patients with higher GRACE risk score. The inflammation-based risk score reclassified 25.3% of the population. The net reclassification index was 8.2% (p=0.001). CONCLUSION: A risk score system based on biomarkers of inflammation readily available at admission in patients with ACS, could better assess the inflammatory status and predict in-hospital mortality, as well as severe systemic inflammation that contributes to a worse outcome independently of clinical risk factors.

Swarm Intelligence-Enhanced Detection of Non-Small-Cell Lung Cancer Using Tumor-Educated Platelets.

Blood-based liquid biopsies, including tumor-educated blood platelets (TEPs), have emerged as promising biomarker sources for non-invasive detection of cancer. Here we demonstrate that particle-swarm optimization (PSO)-enhanced algorithms enable efficient selection of RNA biomarker panels from platelet RNA-sequencing libraries (n = 779). This resulted in accurate TEP-based detection of early- and late-stage non-small-cell lung cancer (n = 518 late-stage validation cohort, accuracy, 88%; AUC, 0.94; 95% CI, 0.92-0.96; p < 0.001; n = 106 early-stage validation cohort, accuracy, 81%; AUC, 0.89; 95% CI, 0.83-0.95; p < 0.001), independent of age of the individuals, smoking habits, whole-blood storage time, and various inflammatory conditions. PSO enabled selection of gene panels to diagnose cancer from TEPs, suggesting that swarm intelligence may also benefit the optimization of diagnostics readout of other liquid biopsy biosources.

p53 Signaling Pathway Polymorphisms Associated With Emphysematous Changes in Patients With COPD.

BACKGROUND: The p53 signaling pathway may be important for the pathogenesis of emphysematous changes in the lungs of smokers. Polymorphism of p53 at codon 72 is known to affect apoptotic effector proteins, and the polymorphism of mouse double minute 2 homolog (MDM2) single nucleotide polymorphism (SNP)309 is known to increase MDM2 expression. The aim of this study was to assess polymorphisms of the p53 and MDM2 genes in smokers and confirm the role of SNPs in these genes in the pathogenesis of pulmonary emphysema. METHODS: This study included 365 patients with a smoking history, and the polymorphisms of p53 and MDM2 genes were identified. The degree of pulmonary emphysema was determined by means of CT scanning. SNPs, MDM2 mRNA, and p53 protein levels were assessed in human lung tissues from smokers. Plasmids encoding p53 and MDM2 SNPs were used to transfect human lung fibroblasts (HLFs) with or without cigarette smoke extract (CSE), and the effects on cell proliferation and MDM2 promoter activity were measured. RESULTS: The polymorphisms of the p53 and MDM2 genes were associated with emphysematous changes in the lung and were also associated with p53 protein and MDM2 mRNA expression in the lung tissue samples. Transfection with a p53 gene-coding plasmid regulated HLF proliferation, and the analysis of P2 promoter activity in MDM2 SNP309-coding HLFs showed the promoter activity was altered by CSE. CONCLUSIONS: Our data demonstrated that p53 and MDM2 gene polymorphisms are associated with apoptotic signaling and smoking-related emphysematous changes in lungs from smokers.

The need to recognize the pulmonary circulation and the right ventricle as an integrated functional unit: facts and hypotheses (2013 Grover Conference series).

For many patients with severe pulmonary arterial hypertension, heart failure-and, in particular, right heart failure-is the final chapter of their chronic illness. Targeted therapy for pulmonary hypertension is effective only if the right ventricular ejection fraction is maintained or improved. Because improvement of right heart function and reversal of right heart failure are treatment goals, it is important to investigate the cellular and molecular mechanisms that cause right heart failure. Here, we propose that right ventricular capillary rarefaction is an important hallmark of right heart failure and consider that the "sick lung circulation" and the pressure-overloaded right ventricle constitute a functional unit.