FAM86A methylation of eEF2 links mRNA translation elongation to tumorigenesis.

eEF2 post-translational modifications (PTMs) can profoundly affect mRNA translation dynamics. However, the physiologic function of eEF2K525 trimethylation (eEF2K525me3), a PTM catalyzed by the enzyme FAM86A, is unknown. Here, we find that FAM86A methylation of eEF2 regulates nascent elongation to promote protein synthesis and lung adenocarcinoma (LUAD) pathogenesis. The principal physiologic substrate of FAM86A is eEF2, with K525me3 modeled to facilitate productive eEF2-ribosome engagement during translocation. FAM86A depletion in LUAD cells causes 80S monosome accumulation and mRNA translation inhibition. FAM86A is overexpressed in LUAD and eEF2K525me3 levels increase through advancing LUAD disease stages. FAM86A knockdown attenuates LUAD cell proliferation and suppression of the FAM86A-eEF2K525me3 axis inhibits cancer cell and patient-derived LUAD xenograft growth in vivo. Finally, FAM86A ablation strongly attenuates tumor growth and extends survival in KRASG12C-driven LUAD mouse models. Thus, our work uncovers an eEF2 methylation-mediated mRNA translation elongation regulatory node and nominates FAM86A as an etiologic agent in LUAD.

Targeting the ADPKD methylome using nanoparticle-mediated combination therapy.

DNA methylation aberrancies are found in autosomal dominant polycystic kidney disease (ADPKD), which suggests the methylome to be a promising therapeutic target. However, the impact of combining DNA methylation inhibitors (DNMTi) and ADPKD drugs in treating ADPKD and on disease-associated methylation patterns has not been fully explored. To test this, ADPKD drugs, metformin and tolvaptan (MT), were delivered in combination with DNMTi 5-aza-2'-deoxycytidine (Aza) to 2D or 3D cystic Pkd1 heterozygous renal epithelial cells (PKD1-Het cells) as free drugs or within nanoparticles to enable direct delivery for future in vivo applications. We found Aza synergizes with MT to reduce cell viability and cystic growth. Reduced representation bisulfite sequencing (RRBS) was performed across four groups: PBS, Free-Aza (Aza), Free-Aza+MT (F-MTAza), and Nanoparticle-Aza+MT (NP-MTAza). Global methylation patterns showed that while Aza alone induces a unimodal intermediate methylation landscape, Aza+MT recovers the bimodality reminiscent of somatic methylomes. Importantly, site-specific methylation changes associated with F-MTAza and NP-MTAza were largely conserved including hypomethylation at ADPKD-associated genes. Notably, we report hypomethylation of cancer-associated genes implicated in ADPKD pathogenesis as well as new target genes that may provide additional therapeutic effects. Overall, this study motivates future work to further elucidate the regulatory mechanisms of observed drug synergy and apply these combination therapies in vivo.

The FAM86 domain of FAM86A confers substrate specificity to promote EEF2-Lys525 methylation.

FAM86A is a class I lysine methyltransferase (KMT) that generates trimethylation on the eukaryotic translation elongation factor 2 (EEF2) at Lys525. Publicly available data from The Cancer Dependency Map project indicate high dependence of hundreds of human cancer cell lines on FAM86A expression. This classifies FAM86A among numerous other KMTs as potential targets for future anticancer therapies. However, selective inhibition of KMTs by small molecules can be challenging due to high conservation within the S-adenosyl methionine (SAM) cofactor binding domain among KMT subfamilies. Therefore, understanding the unique interactions within each KMT-substrate pair can facilitate developing highly specific inhibitors. The FAM86A gene encodes an N-terminal FAM86 domain of unknown function in addition to its C-terminal methyltransferase domain. Here, we used a combination of X-ray crystallography, the AlphaFold algorithms, and experimental biochemistry to identify an essential role of the FAM86 domain in mediating EEF2 methylation by FAM86A. To facilitate our studies, we also generated a selective EEF2K525 methyl antibody. Overall, this is the first report of a biological function for the FAM86 structural domain in any species and an example of a noncatalytic domain participating in protein lysine methylation. The interaction between the FAM86 domain and EEF2 provides a new strategy for developing a specific FAM86A small molecule inhibitor, and our results provide an example in which modeling a protein-protein interaction with AlphaFold expedites experimental biology.

DNA Methylation Dynamics During Esophageal Epithelial Regeneration Following Repair with Acellular Silk Fibroin Grafts in Rat.

Esophageal pathologies such as atresia and benign strictures often require surgical reconstruction with autologous tissues to restore organ continuity. Complications such as donor site morbidity and limited tissue availability have spurred the development of acellular grafts for esophageal tissue replacement. Acellular biomaterials for esophageal repair rely on the activation of intrinsic regenerative mechanisms to mediate de novo tissue formation at implantation sites. Previous research has identified signaling cascades involved in neoepithelial formation in a rat model of onlay esophagoplasty with acellular silk fibroin grafts, including phosphoinositide 3-kinase (PI3K), and protein kinase B (Akt) signaling. However, it is currently unknown how these mechanisms are governed by DNA methylation (DNAme) during esophageal wound healing processes. Reduced-representation bisulfite sequencing is performed to characterize temporal DNAme dynamics in host and regenerated tissues up to 1 week postimplantation. Overall, global hypermethylation is observed at postreconstruction timepoints and an inverse correlation between promoter DNAme and the expression levels of differentially expressed proteins during regeneration. Site-specific hypomethylation targets genes associated with immune activation, while hypermethylation occurs within gene bodies encoding PI3K-Akt signaling components during the tissue remodeling period. The data provide insight into the epigenetic mechanisms during esophageal regeneration following surgical repair with acellular grafts.

Impact of Primary Hemostasis Disorders on Late Major Bleeding Events among Anticoagulated Atrial Fibrillation Patients Treated by TAVR.

BACKGROUND: Bleeding events are among the striking complications following transcatheter aortic valve replacement (TAVR), and bleeding prediction models are crucially warranted. Several studies have highlighted that primary hemostasis disorders secondary to persistent loss of high-molecular-weight (HMW) multimers of the von Willebrand factor (vWF) and assessed by adenosine diphosphate closure time (CT-ADP) may be a strong predictor of late major/life-threatening bleeding complications (MLBCs). Pre-existing atrial fibrillation (AF) is a frequent comorbidity in TAVR patients and potentially associated with increased bleeding events after the procedure. OBJECTIVES: This study evaluated the impact of ongoing primary hemostasis disorders, as assessed by post-procedural CT-ADP > 180 s, on clinical events after TAVR among anticoagulated AF patients. METHODS: An ongoing primary hemostasis disorder was defined by post-procedure CT-ADP > 180 s. Bleeding complications were assessed according to the Valve Academic Research Consortium-2 (VARC-2) criteria. The primary endpoint was the occurrence of late MLBCs at one-year follow-up. The secondary endpoint was a composite of mortality, stroke, myocardial infarction, and rehospitalization for heart failure. RESULTS: In total, 384 TAVR patients were included in the analysis. Of these patients, 57 patients (14.8%) had a prolongated CT-ADP > 180 s. Increased MLBCs were observed in patients with CT-ADP > 180 s (35.1% versus 1.2%; p < 0.0001). Conversely, the occurrence of the composite endpoint did not differ between the groups. Multivariate analysis identified CT-ADP > 180 s (HR 28.93; 95% CI 9.74-85.95; p < 0.0001), bleeding history, paradoxical aortic stenosis (AS), and major vascular complications following TAVR as independent predictors of late MLBCs. CONCLUSION: Among patients with anticoagulated AF, a post-procedural CT-ADP > 180 s was identified as a strong independent predictor of late MLBCs. These findings suggest that persistent primary hemostasis disorders contribute to a higher risk of late bleeding events and should be considered for a tailored, risk-adjusted antithrombotic therapy after TAVR.

Systemic Inflammatory Response Syndrome Is a Major Determinant of Cardiovascular Outcome in Takotsubo Syndrome.

BACKGROUND: Recent insights have emphasized the importance of inflammatory response in takotsubo syndrome (TTS). We sought to evaluate the predictors of systemic inflammatory response syndrome (SIRS) and its impact on cardiovascular mortality after TTS.Methods and Results:The 215 TTS patients were retrospectively included between September 2008 and January 2018. SIRS was diagnosed in 96 patients (44.7%). They had lower left ventricular ejection fraction (LVEF) on admission (34.5% vs. 41.9%; P<0.001) and higher peak brain natriuretic peptide and troponin. At a median follow-up of 518 days, SIRS was associated with increased in-hospital mortality (14.6% vs. 5.0%; P=0.019), overall mortality (29.4% vs. 10.8%; P=0.002), and cardiovascular mortality (10.6% vs. 2.1%; P=0.026). A history of cancer (OR, 3.36; 95% CI: 1.54-7.31; P=0.002) and LVEF <40% at admission (OR, 2.31; 95% CI: 1.16-4.58; P=0.017) were identified as independent predictors of SIRS. On multivariate Cox regression analysis, SIRS (HR, 12.8; 95% CI: 1.58-104; P=0.017), age (HR, 1.09; 95% CI: 1.02-1.16; P=0.01), and LVEF <40% at discharge (HR, 9.88; 95% CI: 2.54-38.4; P=0.001) were independent predictors of cardiovascular death. CONCLUSIONS: SIRS was found in a large proportion of TTS patients and was associated with enhanced myocardial damage and adverse outcome in the acute phase. At long-term follow-up, SIRS remained an independent factor of cardiovascular death.

Biophysical and epigenetic regulation of cancer stemness, invasiveness and immune action.

PURPOSE OF REVIEW: The tumor microenvironment (TME) is an amalgam of multiple dysregulated biophysical cues that can alter cellular behavior through mechanotransductive signaling and epigenetic modifications. Through this review, we seek to characterize the extent of biophysical and epigenetic regulation of cancer stemness and tumor-associated immune cells in order to identify ideal targets for cancer therapy. RECENT FINDINGS: Recent studies have identified cancer stemness and immune action as significant contributors to neoplastic disease, due to their susceptibility to microenvironmental influences. Matrix stiffening, altered vasculature, and resultant hypoxia within the TME can influence cancer stem cell (CSC) and immune cell behavior, as well as alter the epigenetic landscapes involved in cancer development. SUMMARY: This review highlights the importance of aberrant biophysical cues in driving cancer progression through altered behavior of CSCs and immune cells, which in turn sustains further biophysical dysregulation. We examine current and potential therapeutic approaches that break this self-sustaining cycle of disease progression by targeting the presented biophysical and epigenetic signatures of cancer. We also summarize strategies including the normalization of the TME, targeted drug delivery, and inhibition of cancer-enabling epigenetic players.

Primary Hemostatic Disorders and Late Major Bleeding After Transcatheter Aortic Valve Replacement.

BACKGROUND: Periprocedural and late (>30 days) bleedings represent major complications after transcatheter aortic valve replacement and have been identified as potential areas for improved patient care. OBJECTIVES: The authors sought to evaluate the impact of ongoing primary hemostasis disorders on late major/life-threatening bleeding complications (MLBCs). METHODS: Bleedings were assessed according to the VARC-2 (Valve Academic Research Consortium-2) criteria. Closure time of adenosine diphosphate (CT-ADP), a surrogate marker of high molecular weight von Willebrand multimers proteolysis was assessed 24 h after the procedure. Ongoing primary hemostasis disorder was defined by a CT-ADP >180 s. RESULTS: Among 372 patients who survived at 30 days, MLBCs occurred in 42 patients (11.3%) at a median follow-up of 383 days (interquartile range: 188 to 574 days). MLBCs were mainly of gastrointestinal origin (42.8%) and were associated with increased overall mortality (hazard ratio [HR]: 5.66; 95% confidence interval [CI]: 3.10 to 10.31; p < 0.001) and cardiac mortality (HR: 11.62; 95% CI: 4.59 to 29.37; p < 0.001). A 2.5-fold elevation of MLBCs could be evidenced in patients with a CT-ADP > 180 s (27.4% vs. 11.5%; p < 0.001). Multivariate regression analysis identified paravalvular leak (PVL) (HR: 6.31; 95% CI: 3.43 to 11.60; p < 0.0001) and CT-ADP > 180 s (HR: 3.08; 95% CI: 1.62 to 5.81; p = 0.0005) as predictor of MLBCs. CONCLUSIONS: MLBCs after transcatheter aortic valve replacement are frequent and associated with an increased morbidity and mortality. PVL and CT-ADP >180 s were identified as strong predictors for MLBCs. These findings strongly suggest that persistent HMW defects contribute to enhanced bleeding risk in patients with residual PVL.

CT-ADP Point-of-Care Assay Predicts 30-Day Paravalvular Aortic Regurgitation and Bleeding Events following Transcatheter Aortic Valve Replacement.

BACKGROUND: Paravalvular aortic regurgitation (PVAR) remains a frequent postprocedural concern following transcatheter aortic valve replacement (TAVR). Persistence of flow turbulence results in the cleavage of high-molecular-weight von Willebrand multimers, primary haemostasis dysfunction and may favour bleedings. Recent data have emphasized the value of a point-of-care measure of von Willebrand factor-dependent platelet function (closure time [CT] adenosine diphosphate [ADP]) in the monitoring of immediate PVAR. This study examined whether CT-ADP could detect PVAR at 30 days and bleeding complications following TAVR. METHODS: CT-ADP was assessed at baseline and the day after the procedure. At 30 days, significant PVAR was defined as a circumferential extent of regurgitation more than 10% by transthoracic echocardiography. Events at follow-up were assessed according to the Valve Academic Research Consortium-2 consensus classification. RESULTS: Significant PVAR was diagnosed in 44 out of 219 patients (20.1%). Important reduction of CT-ADP could be found in patients without PVAR, contrasting with the lack of CT-ADP improvement in significant PVAR patients. By multivariate analysis, CT-ADP > 180 seconds (hazard ratio [HR]: 5.1, 95% confidence interval [CI]: 2.5-10.6; p < 0.001) and a self-expandable valve were the sole independent predictors of 30-day PVAR. At follow-up, postprocedural CT-ADP >180 seconds was identified as an independent predictor of major/life-threatening bleeding (HR: 1.7, 95% CI [1.0-3.1]; p = 0.049). Major/life-threatening bleedings were at their highest levels in patients with postprocedural CT-ADP > 180 seconds (35.2 vs. 18.8%; p = 0.013). CONCLUSION: Postprocedural CT-ADP > 180 seconds is an independent predictor of significant PVAR 30 days after TAVR and may independently contribute to major/life-threatening bleedings.

Impact of Malignancies in the Early and Late Time Course of Takotsubo Cardiomyopathy.

BACKGROUND: Although the relationship between malignancies and catecholamine-induced myocardial stunning remains largely speculative, it has been suggested that the presence of cancer may lower the threshold for stress stimuli and/or may aggravate cardiac adrenoreceptor sensitivity. We sought to investigate whether associations exist between a previous or current diagnosis of malignancy, diagnostic parameters during hospitalization and death in takotsubo. METHODS AND RESULTS: The 154 takotsubo patients were retrospectively identified between May 2008 and December 2014. Previous history of malignancy was identified in 44 patients (28.5%). Cardiac arrest was present at admission in 13 patients (8.4%). Intra-aortic balloon pump was inserted in 16 patients (10.4%). In patients with malignancy, higher B-type natriuretic peptide (BNP), leukocyte and C-reactive protein (CRP) peaks could be observed during the hospital phase. Initial impairment of left ventricular ejection fraction was negatively related to BNP, leukocyte, and CRP peaks. At a median follow-up of 364 days, all-cause death occurred in 41 patients (26.6%) and cardiac death in 12 patients (7.7%). Multivariate Cox regression analysis identified malignancy (hazard ratio 4.77 (1.02-22.17), leukocyte peak and age as independent predictors of cardiac death. Malignancy (2.62 (1.26-5.44), leukocyte peak (1.05 (1.01-1.08) and initial cardiac arrest (6.68 (2.47-18.01) were identified as independent predictors of overall mortality. CONCLUSIONS: In the present takotsubo patients, the prevalence of malignancy was high and may have affected cardiovascular outcomes through the activation of inflammatory and neurohormonal mechanisms. (Circ J 2016; 80: 2192-2198).

First report of trastuzumab treatment after postoperative Takotsubo cardiomyopathy.

BACKGROUND: Trastuzumab is a humanized monoclonal antibody used for the treatment of HER2-positive breast cancer. Cardiotoxicity is a well-known adverse event of trastuzumab use but little has been documented regarding its use in patients with a history of cardiac disease. CASE REPORT: We describe a case in which trastuzumab treatment was administered to a 40-year-old female patient with early breast cancer after acute heart failure secondary to postoperative Takotsubo cardiomyopathy. After one year of follow-up with close monitoring by echocardiography, there have been no heart-related symptoms. Additional surgery was performed because of positive resection margins at first surgery, without complications, despite the risk of recurrence of Takotsubo cardiomyopathy. CONCLUSION: Trastuzumab can be safely administered after acute heart failure secondary to postoperative Takotsubo cardiomyopathy.