Rationale
In the failing heart, persistent β-adrenergic receptor (βAR) activation is thought to induce myocyte death by protein kinase A (PKA)-dependent and PKA-independent activation of calcium/calmodulin-dependent kinase II (CaMKII). β-Adrenergic signaling pathways are also capable of activating cardioprotective mechanisms.
Objective
This study used a novel PKA inhibitor peptide (PKI) to inhibit PKA activity to test the hypothesis that βAR signaling causes cell death through PKA-dependent pathways and cardioprotection through PKA-independent pathways.
Methods and Results
In PKI transgenic mice, chronic isoproterenol (ISO) failed to induce cardiac hypertrophy, fibrosis, myocyte apoptosis and depressed cardiac function. In cultured adult feline ventricular myocytes (AFVMs), PKA inhibition protected myocytes from death induced by β1-AR agonists by preventing cytosolic and SR Ca2+ overload and CaMKII activation. PKA inhibition revealed a cardioprotective role of β-adrenergic signaling via cAMP/EPAC /Rap1/Rac/ERK pathway. Selective PKA inhibition causes protection in the heart after myocardial infarction (MI) that was superior to β-blocker therapy.
Conclusion
These results suggest that selective block of PKA could be a novel heart failure therapy.
Introduction: Tislelizumab, an anti-programmed cell death protein-1 antibody, was specifically engineered to minimize FcɣR macrophage binding to abrogate antibody-dependent phagocytosis. Compared with chemotherapy alone, tislelizumab plus chemotherapy may improve clinical outcomes in patients with advanced nonsquamous NSCLC (nsq-NSCLC).
Methods:In this open-label phase 3 trial (RATIONALE 304; NCT03663205), patients with histologically confirmed stage IIIB or IV nsq-NSCLC were randomized (2:1) to receive either arm A: tislelizumab plus platinum (carboplatin or cisplatin) and pemetrexed every 3 weeks (Q3Ws) or arm B: platinum and pemetrexed alone Q3W during induction treatment, followed by intravenous maintenance
Pathological cardiac hypertrophy (PCH) is associated with the development of arrhythmia and congestive heart failure. While calcium (Ca 2+ ) is implicated in hypertrophic signaling pathways, the specific role of Ca 2+ influx through the L-type Ca 2+ channel (I Ca-L ) has been controversial and is the topic of this study. To determine if and how sustained increases in I Ca-L induces PCH, transgenic mouse models with low (LE) and high (HE) expression levels of the β2a subunit of Ca 2+ channels (β2a) and in cultured adult feline (AF) and neonatal rat (NR) ventricular myocytes (VMs) infected with an adenovirus containing a β2a-GFP.Results-In vivo, β2a LE and HE mice had increased heart weight to body weight ratio, posterior wall and interventricular septal thickness, tissue fibrosis, myocyte volume and cross sectional area and the expression of PCH markers in a time-and dose-dependent manner. PCH was associated with a hypercontractile phenotype including enhanced I Ca-L , fractional shortening, peak Ca 2+ transient, at the myocyte level, greater ejection fraction and fractional shortening at the organ level. In addition, LE mice had an exaggerated hypertrophic response to transverse aortic constriction. In vitro overexpression of β2a in cultured AFVMs increased I Ca-L , cell volume, protein synthesis, NFAT and HDAC translocations and in NRVMs increased surface area. These effects were abolished by the blockade of I Ca-L , intracellular Ca 2+ , calcineurin, CaMK II and SERCA.Conclusion-Increasing I Ca-L is sufficient to induce PCH through the calcineurin/NFAT and CaMKII/HDAC pathways. Both cytosolic and SR/ER-nuclear envelop Ca 2+ pools were shown to be involved.
Recently, dysregulation of microRNAs plays a critical role in cancer metastasis. Here, an in vivo selection approach was used to generate highly aggressive NSCLC sub-cell lines followed by comparing the microRNAs expression using microarrays. miR-124 was notably deregulated in both highly invasive sub-cell lines and node-positive NSCLC specimens. Over-expression of miR-124 robustly attenuated migration and metastatic ability of the aggressive cells. MYO10 was subsequently identified as a novel functional downstream target of miR-124, and was up-regulated in node-positive NSCLC tissues. Knockdown of MYO10 inhibited cell migration, whereas forced MYO10 expression markedly rescued miR-124-mediated suppression of cell metastasis. Additionally, we found an activated NF-κB-centered inflammatory loop in the highly aggressive cells leading to down-regulation of miR-124. These results suggest that NF-κB-regulated miR-124 targets MYO10, inhibits cell invasion and metastasis, and is down-regulated in node-positive NSCLC.
In young mdx mice, the myocyte increases its contractile function to compensate for myocyte loss. However, these myocytes with enhanced baseline function have reduced potential for stimulation, decreased β1-AR density/sensitivity, leading to blunted cardiac beta-adrenergic response.
The highest incidence of VTE is within 1 month after lung cancer surgery. High risk factors for VTE include incomplete surgical resection, postoperative use of anti-angiogenesis drugs, EGFR-TKI application and an increase in preoperative D-dimer level.
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