Transcriptome-Wide N6-Methyladenosine Alternations in Pulmonary Arteries of Monocrotaline-Induced Pulmonary Arterial Hypertension in Rats and Novel Therapeutic Targets.

N6-methyladenosine (m6A) is a post-transcriptional epigenetic change with transcriptional stability and functionality regulated by specific m6A-modifying enzymes. However, the significance of genes modified by m6A and enzymes specific to m6A regulation in the context of pulmonary arterial hypertension (PAH) remains largely unexplored. MeRIP-seq and RNA-seq were applied to explore variances in m6A and RNA expression within the pulmonary artery tissues of control and monocrotaline-induced PAH rats. Functional enrichments were analyzed using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. To screen candidate m6A-related genes, the STRING and Metascape databases were used to construct a protein-protein interaction network followed by a real-time PCR validation of their expression. The expression level of an m6A regulator was further investigated using immunohistochemical staining, immunofluorescence, and Western blot techniques. Additionally, proliferation assays were conducted on primary rat pulmonary artery smooth muscle cells (PASMCs). We identified forty-two differentially expressed genes that exhibited either hypermethylated or hypomethylated m6A. These genes are predominantly related to the extracellular matrix structure, MAPK, and PI3K/AKT pathways. A candidate gene, centromere protein F (CENPF), was detected with increased expression in the PAH group. Additionally, we first identified an m6A reader, leucine rich pentatricopeptide repeat containing (LRPPRC), which was downregulated in the PAH rat model. The in vitro downregulation of Lrpprc mediated by siRNA resulted in the enhanced proliferation and elevated expression of Cenpf mRNA in primary rat PASMCs. Our study revealed a modified transcriptome-wide m6A landscape and associated regulatory mechanisms in the pulmonary arteries of PAH rats, potentially offering a novel target for therapeutic strategies in the future.

Mechanisms of unusual response to lipid-lowering therapy: PCSK9 inhibition.

The efficacy of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition has broadened lipid-lowering therapy thus providing decreased risk in atherosclerotic cardiovascular disease. Unfortunately, the widespread use of PCSK9 inhibitors (PCSK9i), ie, monoclonal antibodies, has led to the findings of unusual responsiveness, ie, a phenomenon defined as an LDL-C reduction of <30% vs the average LDL-C reduction efficacy of 50-60%. This unusual responsiveness to PCSK9i is attributable to several factors, ie, lack of adherence, impaired absorption, poor distribution or early elimination as well as abnormal effects of PCSK9i in the presence of anti-antibodies or mutations in PCSK9 and LDLR. Unexpectedly increased lipoprotein (Lp)(a) also appear to contribute to the unusual responsiveness scenario. Identification of these responses and mechanisms underlying them are essential for effective management of LDL-C and cardiovascular risk. In this review, we describe plausible reasons underlying this phenomenon supported by findings of clinical trials. We also elaborate on the need for education and regular follow-up to improve adherence. Collectively, the review provides a summary of the past, present, and future of mechanisms and countermeasures revolving around unusual responses to PCSK9i therapy.

Clinical Profile and Prognosis of Hereditary Transthyretin Amyloid Cardiomyopathy: A Single-Center Study in South China.

Background: Hereditary transthyretin amyloid cardiomyopathy (ATTR-CM) is a genotypically heterogeneous disorder with a poor prognosis. There is limited literature describing the variants responsible for ATTRv in areas outside the United State, the United Kingdom and Europe. This study was performed to describe the clinical characteristics and genotypic profiles of this disease in South China. Methods: This was a single-center retrospective study that evaluated 29 patients with a confirmed diagnosis of hereditary transthyretin amyloid cardiomyopathy enrolled from January 2016 to November 2021. Results: 93.1% patients were male and the median age of symptom onset was 53 (46, 62.5) years old. The initial manifestations of ATTR-CM were cardiovascular symptoms (55.2%), neuropathy (41.4%) and vitreous opacity (3.4%). Phenotypes at diagnosis were mixed (82.8%), predominant cardiac (6.9%), neurological (6.9%) and ophthalmic (3.4%). Poor R-wave progression (41%), pseudo-infarct (31%) and low-voltage (31%) patterns were common findings on electrocardiogram. Unexplained increased wall thickness was observed in all 29 patients, with mean septal and posterior wall thicknesses of 14.25 ± 6.26 mm and 15.34 ± 2.84 mm, respectively. Diastolic dysfunction was also seen in all 29 patients, and 17 (58%) had a restrictive fill pattern at diagnosis. Nine different missense mutations of the TTR gene were found in 29 patients from 23 families, with c.349G>T (p.Ala117Ser) the most common mutation. The median survival time after diagnosis was 47.6 (95% CI 37.9-57.4) months, with 1, 3 and 5-year survival rates of 91.2%, 74% and 38% respectively. Patients with advanced heart failure (National Amyloidosis Staging stage II/III) had worse survival than stage I [Breslow (Generalized Wilcoxon), χ2 = 4.693, P = 0.03)]. Conclusions: ATTR amyloidosis genotypes and phenotypes are highly heterogeneous. Advanced heart failure predicts a poor prognosis. Understanding the different clinical profiles of ATTR cardiac amyloidosis with different genotype is important to its early recognition.

N-acetyl cysteine ameliorates aortic fibrosis by promoting M2 macrophage polarization in aging mice.

Background: Vascular fibrosis is a universal phenomenon associated with aging, and oxidative stress plays an important role in the genesis of vascular damage in line with the aging process. However, whether antioxidants can ameliorate vascular fibrosis remains unclear.Objectives: The present study was to determine antioxidant N-acetylcysteine (NAC) could ameliorates aortic fibrosis in aging wild-type C57BL/6 mice.Methods: The aortas were harvested from both 12-week and 60-week wild-type mice. The 60-week mice were treated with and without the NAC for 12 weeks starting at the age of 48 weeks. Hematoxylin and eosin (H&E) staining and Masson's trichrome staining of aortic samples were performed, and the levels of reactive oxygen species (ROS), RNA expression of GAPDH, TNF-α, MCP-1, IL-6, IL-10, IL-4, SIRT-1, SIRT-3, FOXO-1, and macrophage polarization were determined.Results: There is a positive relationship between collagen deposition and the M1/M2 macrophage ratio in the aortic wall of aged wild-type C57BL/6 mice. The higher collagen area percentage in the aortas of 60-week-old mice than in 12-week-old mice was reversed by NAC. NAC could not impact the total number of macrophages, but partly promoted M2 macrophage polarization. By performing qRT-PCR using aortic samples from these mice, we identified that SIRT-1, SIRT-3, FOXO-1 could be somehow responsible for aging-related fibrosis.Conclusions: NAC ameliorates aortic fibrosis in aging wild type mice partly by promoting M2 macrophage polarization.

Aberrant Mitochondrial Dynamics: An Emerging Pathogenic Driver of Abdominal Aortic Aneurysm.

Abdominal aortic aneurysm (AAA) is defined as a progressive segmental dilation of the abdominal aorta and is associated with high mortality. The characterized features of AAA indicate several underlying mechanisms of AAA formation and progression, including reactive oxygen species production, inflammation, and atherosclerosis. Mitochondrial functions are critical for determining cell fate, and mitochondrial dynamics, especially selective mitochondrial autophagy, which is termed as mitophagy, has emerged as an important player in the pathogenesis of several cardiovascular diseases. The PARKIN/PARIS/PGC1α pathway is associated with AAA formation and has been proposed to play a role in mitochondrial dynamics mediated by the PINK/PARKIN pathway in the pathogenesis underlying AAA. This review is aimed at deepening our understanding of AAA formation and progression, which is vital for the development of potential medical therapies for AAA.

Evaluation of variation in D-dimer levels among COVID-19 and bacterial pneumonia: a retrospective analysis.

In the recent outbreak of novel coronavirus infection worldwide, the risk of thrombosis and bleeding should be concerned. We aimed to observe the dynamic changes of D-dimer levels during disease progression to evaluate their value for thrombosis. In this study, we report the clinical and laboratory results of 57 patients with confirmed COVID-19 pneumonia and 46 patients with confirmed community-acquired bacterial pneumonia (CAP). And their concentrations of D-dimer, infection-related biomarkers, and conventional coagulation were retrospectively analyzed. The Padua prediction score is used to identify patients at high risk for venous thromboembolism (VTE). The results found that, on admission, both in COVID-19 patients and CAP patients, D-dimer levels were significantly increased, and compared with CAP patients, D-dimer levels were higher in COVID-19 patients (P < 0.05). Besides, we found that in COVID-19 patients, D-dimer were related with markers of inflammation, especially with hsCRP (R = 0.426, P < 0.05). However, there was low correlation between VTE score and D-dimer levels (Spearman's R = 0.264, P > 0.05) weakened the role of D-dimer in the prediction of thrombosis. After treatments, D-dimer levels decreased which was synchronous with hsCRP levels in patients with good clinical prognosis, but there were still some patients with anomalous increasing D-dimer levels after therapy. In conclusion, elevated baseline D-dimer levels are associated with inflammation but not with VTE score in COVID-19 patients, suggesting that it is unreasonable to judge whether anticoagulation is needed only according to D-dimer levels. However, the abnormal changes of D-dimer and inflammatory factors suggest that anticoagulant therapy might be needed.

Predicting worse survival for newly diagnosed T cell lymphoma based on the decreased baseline CD16-/CD16 + monocyte ratio.

T cell non-Hodgkin lymphoma (T-NHL) is highly invasive and heterogeneous without accurate prognosis prediction. We proposed peripheral CD16-/CD16 + monocytes the additional indicators for T-NHL prognosis. We prospectively recruited 31 T-NHL patients without previous treatment. The CD16-/CD16 + monocyte ratio before chemotherapy was calculated and regular follow up was performed to calculate prognostic prediction value. Tumor associated macrophages (TAM) in tumor tissue were counted and transcriptome sequencing of CD16- and CD16 + monocytes was applied to explore potential mechanisms. We found that T-NHL patients had higher ratio of total monocytes especially the CD16 + monocytes along with a decreased ratio of CD16-/CD16 + monocytes, compared to the health control. The 1-year overall survival rate was 0.492 and 0.755 for CD16- monocyte/CD16 + monocyte ratio of <11 and ≥11(p < 0.05), respectively. The peripheral CD16-/CD16 + monocyte ratio was significantly relevant with the pathological CD68/CD206 macrophage ratio. The differently expressed genes in CD16- and CD16 + monocytes from T-NHL patients were mainly involved in signaling molecules related to tumor microenvironment. Pro-tumor genes were identified in monocyte subsets especially in CD16 + monocytes. In conclusion, the ratio of peripheral CD16-/CD16 + monocyte helps to stratify the prognosis of T-NHL. The relatively increased CD16 + monocytes may contribute to the pro-tumor microenvironment of T-NHL.

The combination of methotrexate and cytosine arabinoside in newly diagnosed adult Langerhans cell histiocytosis: a prospective phase II interventional clinical trial.

BACKGROUND: Langerhans Cell Histiocytosis (LCH) is a rare disease puzzling both children and adults, however outcome of adult patients is unfavorable. This prospective interventional trial aims to test the efficacy and safety of the combination of methotrexate and cytosine arabinoside in adult LCH patients. METHOD: A total of 36 patients enrolled diagnosed with LCH and treated in our center from 1st Jan, 2014 to 30th Jun, 2016. RESULT: Nineteen patients underwent the detection of BRAF mutation, with a positive rate of 21.1%. The overall response rate was 100%, only 16.7% achieved complete response. The overall regression rate of osseous lesions was 100%. Regression of central nervous system involvement was also favorable. After a median follow-up of 44 months, the estimated event-free survival was 48.9 months, the overall survival rate was 97.2%. The risk organ involvement showed strong prognostic value, EFS was 34.1 or 54.6 months (p = 0.001) in groups with/without risk organ involvement respectively. Neutropenia and thrombocytopenia were the most common adverse effects. CONCLUSION: The regimen of methotrexate and cytosine arabinoside (MA) is effective and safe in treating adult LCH patients, and timely preventions may be considered for the high incidence of hematological adverse effects. TRIAL REGISTRATION: Trial No. NCT02389400 on Clinicaltrials.gov, registered on 10th Mar. 2015.

Efficacy and safety of HD-MTX based systemic chemotherapy regimens: retrospective study of induction therapy for primary central nervous system lymphoma in Chinese.

We performed a retrospective study of 49 patients with newly diagnosed primary central nervous system lymphoma (PCNSL), to compare the efficacy and safety of different high-dose methotrexate (HD-MTX) based systemic chemotherapy regimens as induction therapy. 25 patients received AB ± R alternative regimen (consist methotrexate, ifosfamide, vindesine, dexamethasone, carmustine and teniposide), while others received HD-MTX ± R regimen. The complete response rate and overall response rate of AB ± R group and HD-MTX ± R group were 36.83% vs. 33.33%, and 68.42% vs. 71.43%, while the 2-year OS and PFS rate were 71.43% vs. 74.62%, and 42.86% vs. 54.64%, respectively. In Age > 60 subgroup, the 2-year OS and PFS rate of AB ± R group and HD-MTX ± R group were 81.82% vs. 33.33%, and 54.55% vs. 33.33%. No significant differences were found in grade 3 or 4 toxicity rate. Generally, HD-MTX ± R regimen was not inferior to AB ± R alternative regimen, but AB ± R alternative regimen seemed achieving more survival benefits in the elderly. We suggest to adjust HD-MTX ± R regimen by changing the dose-reduction strategy especially in elderly patients and adding other powerful drugs that can well penetrate blood-brain barrier to improve the efficacy.

Prognostic implication of leucocyte subpopulations in diffuse large B-cell lymphoma.

BACKGROUND: Recent studies have suggested that variables related to host adaptive immunity and the tumor microenvironment may predict the outcome in patients with non-Hodgkin's lymphoma. This study was undertaken to determine the prognostic value of peripheral blood leucocyte subpopulations in diffuse large-B-cell lymphoma patients. METHODS: We prospectively analyzed the 16 leukocyte subpopulations using Cytodiff flow cytometric technique in a cohort of 45 diffuse large-B-cell lymphoma patients at a single institution between February and December 2014. The Cox proportional hazards model was used to evaluate prognostic factors for overall survival and progression free survival. RESULTS: Diffuse large-B-cell lymphoma patients had decreased cytotoxic and non-cytotoxic NK&T cells as well as increased CD16+ monocytes, CD16- monocytes and mature neutrophils. The decreased CD16- monocyte/CD16+ monocyte ratio and increased mature neutrophil/cytotoxic NK&T cell ratio were related to poor progression-free and overall survival outcome in single and multivariate analysis. The co-constructed model using International Prognostic Index and mature neutrophil/cytotoxic NK&T cell ratio can also help discriminate the clinical outcome. CONCLUSIONS: The decreased CD16-monocyte/CD16+monocyte ratio and increased mature neutrophil/cytotoxic NK&T cell ratio predict poor prognosis in diffuse large-B-cell lymphoma patients. This finding provides a strong rationale for the study of cellular immunotherapy in B-cell lymphoma.

Autologous stem cell transplantation as frontline strategy for peripheral T-cell lymphoma: A single-centre experience.

Objective To determine the efficacy and prognosis of autologous hematopoietic stem cell transplantation (ASCT) as frontline treatment for peripheral T cell lymphoma (PTCL). Methods Clinical data from 46 PTCL patients who achieved complete (CR) or partial remission (PR) after ASCT from October 1996 to July 2014 were analysed retrospectively. Results Median patient age was 32 (range: 15-68) years. Disease types included PTCL, unspecified type, in 23 patients, anaplastic large cell lymphoma in eight, angioimmunoblastic lymphoma in eight, extranodal NK/T-cell lymphoma in five, and hepatosplenic T-cell lymphoma and enteropathy associated T-cell lymphoma in one each. Of these patients, 80% had Prognostic Index for Peripheral T-cell Lymphoma scores ≥1. Thirty-four patients had pre-transplantation CR and 12 had PR. Median follow up was 37 (6-176) months. The 5-year overall survival (OS) and progression-free survival (PFS) rates were 77.1% and 61.9%, respectively. Multivariate analysis showed that pre-transplantation CR was an independent risk factor for survival, and CR was more common than PR (OS 81% vs 59.3%; PFS 71.8% vs 17.8%). Conclusion Frontline consolidation treatment with ASCT was associated with favourable outcomes in patients with PTCL. Pre-transplantation CR was a prognostic factor for survival, suggesting that ASCT may be favoured as front-line consolidation therapy after first complete remission.