CNOT3 targets negative cell cycle regulators in non-small cell lung cancer development

Lung cancer is one of the major causes of cancer death and clarification of its molecular pathology is highly prioritized. The physiological importance of mRNA degradation through the CCR4-NOT deadenylase has recently been highlighted. For example, mutation in CNOT3, a gene coding for CNOT3 subunit of the CCR4-NOT complex, is found to be associated with T-cell acute lymphoblastic leukemia, T-ALL, though its contribution to other cancers has not been reported. Here, we provide evidence suggesting that CNOT3 is required for the growth of non-small cell lung cancer. Depletion of CNOT3 suppresses proliferation of A549 human non-small cell lung cancer cells with enhanced mRNA stability and subsequent elevated expression of p21. In addition, we identified the mRNA for Kruppel-like factor 2 transcription factor, an inducer of p21, as a novel mRNA degradation target of CNOT3 in non-small cell lung cancer cells. Aberrant up-regulation of Kruppel-like factor 2 by CNOT3 depletion leads to impairment in the proliferation of A549 cells. Consistent with these findings, elevated mRNA expression of CNOT3 in non-small cell lung cancer in comparison with the paired normal lung epithelium was confirmed through scrutinization of the RNA-sequencing datasets from The Cancer Genome Atlas. Moreover, we found an inverse correlation between CNOT3 and CDKN1A (encoding p21) mRNA expression using the combined datasets of normal lung epithelium and non-small cell lung cancer. Thus, we propose that the up-regulation of CNOT3 facilitates the development of non-small cell lung cancer through down-regulation of Kruppel-like factor 2 and p21, contrary to tumor suppressive functions of CNOT3 in T-ALL

Current state of therapeutic development for rare cancers in Japan, and proposals for improvement

This article discusses current obstacles to the rapid development of safe and effective treatments for rare cancers, and considers measures required to overcome these challenges. In order to develop novel clinical options for rare cancers, which tend to remain left out of novel therapeutic development because of their paucity, efficient recruitment of eligible patients, who tend to be widely dispersed across the country and treated at different centers, is necessary. For this purpose, it is important to establish rare cancer registries that are linked with clinical studies, to organize a central pathological diagnosis system and biobanks for rare cancers, and to consolidate patients with rare cancers to facilities that can conduct clinical studies meeting international standards. Establishing an all‐Japan cooperative network is essential. Clinical studies of rare cancers have considerable limitations in study design and sample size as a result of paucity of eligible patients and, as a result, the level of confirmation of the efficacy and safety shown by the studies is relatively low. Therefore, measures to alleviate these weaknesses inherent to external conditions need to be explored. It is also important to reform the current research environment in order to develop world‐leading treatment for rare cancers, including promotion of basic research, collaboration between industry and academia, and improvement of the infrastructure for clinical studies. Collaboration among a wide range of stakeholders is required to promote the clinical development of treatment for rare cancers under a nationwide consensus

Association between intensive care unit delirium and delusional memory after critical care in mechanically ventilated patients

AimTo determine the relationship between the delirium of patients with mechanical ventilation during intensive care unit (ICU) stay and delusional memory after ICU discharge.DesignProspective cohort study.MethodsDelirium in adult patients who received mechanical ventilation for more than 24 hr was assessed twice daily using the Confusion Assessment Method for the ICU. Delusional memories were evaluated using the ICU Memory Tool 5–10 days after ICU discharge. The associations between the presence of delirium during the ICU stay and delusional memories were evaluated.ResultsOf 60 enrolled patients, 62% had delirium during their ICU stay, and 68% experienced delusional memories 5–10 days after discharge. Delirium during ICU stay was an independent factor to experience delusional memories following discharge. Preventing delirium during ICU stay might reduce delusional memory. We recommend that patients with delirium during their ICU stay should be carefully followed up after discharge from the ICU

Effects of Closed Vs. Open Repeated Endotracheal Suctioning During Mechanical Ventilation on the Pulmonary and Circulatory Levels of Endothelin-1 in Lavage-Induced Rabbit ARDS Model

Background: A growing body of evidence demonstrates discretely the difference of open endotracheal suctioning (OES) and closed endotracheal suctioning (CES) on the respiratory and hemodynamic parameters in acute respiratory distress syndrome (ARDS). Endothelin-1 (ET-1), a mediator of vascular inflammation, cell proliferation, and fibrosis in addition to being a potent vasoconstrictor has been potentially implicated in the pathogenesis of ARDS. Here, we investigated the effects of repeated OES vs. CES during mechanical ventilation on circulatory and pulmonary levels of ET-1 in ARDS. Methods: Briefly, 22 Japanese White Rabbits were intubated with a 3.5-mm endotracheal tube. Normal saline was instilled into lung and washed mildly. After instillation, rabbits were ventilated at definite setting; OES and CES duration was for 6 hours and performed every 30 minutes from protocol start. Results: At circulatory level, either OES or CES did not alter plasma ET-1 level compared to the ET-1 level in ARDS before the initiation of endotracheal suctioning (OES 4.7 ± 1.3 pg/ml vs. CES 4.8 ± 1.5 pg/ml, p=0.839). In contrast, pulmonary ET-1 level was significantly higher in CES group compared to OES group after 6 hours of repeated suctioning in ARDS (OES 26.9 ± 2.2 pg/mg vs. CES 29.9 ± 3.3 pg/mg, p=0.018). This change in pulmonary ET-1 level could maintain a parallel relation with PaO2 level. Conclusion: At this moment, we cannot clarify the mechanism and effects of the observed change in ET-1 in a rabbit model of ARDS as well as its clinical impact.Research Articl

Fish oil constituent eicosapentaenoic acid inhibits endothelin-induced cardiomyocyte hypertrophy via PPAR-α

AimsA growing body of evidence shows the cardiovascular benefits of fish oil ingredients, including eicosapentaenoic acid (EPA), in humans and experimental animals. However, the effects of EPA on endothelin (ET)-1-induced cardiomyocyte hypertrophy and the involved signaling cascade are largely unknown. A previous study has demonstrated that peroxisomal proliferator-activated receptor (PPAR)-α ligand (fenofibrate) prevents ET-1-induced cardiomyocyte hypertrophy. Although EPA is a ligand of PPAR-α, to date, no study has examined a relationship between EPA and PPAR-α in cardiomyocyte hypertrophy. Here, we investigated whether EPA can block ET-1-induced cardiomyocyte hypertrophy and the possible underlying mechanisms.Main methodsAt day 4 of culture, neonatal rat cardiomyocytes were divided into four groups: control, control cells treated with EPA (10 μM), ET-1 (0.1 nM) administered only and EPA-pre-treated ET-1 administered groups. Also, the cardiomyocytes were treated with PPAR-α siRNA in order to elucidate the mechanisms that may underlie suppression of hypertrophy via the EPA-PPAR system.Key findingsFollowing ET-1 treatment, 2.12- and 1.92-fold increases in surface area and total protein synthesis rate in cardiomyocytes, respectively, were observed and these changes were greatly blocked by EPA pre-treatment. Further, the expression of PPAR-α increased in EPA-treated groups. PPAR-PPRE binding activity was suppressed in ET-1 administered cardiomyocyte and this suppression was improved by EPA treatment. Lastly, pre-treatment of cardiomyocytes with PPAR-α siRNA prior to EPA treatment attenuated the suppressing effects of EPA on cardiomyocyte hypertrophy.SignificanceIn conclusion, the present study shows that EPA attenuates ET-1 induced cardiomyocyte hypertrophy by up regulating levels of PPAR-α pathway

Hyperinflation deteriorates arterial oxygenation and lung injury in a rabbit model of ARDS with repeated open endotracheal suctioning

BackgroundHyperinflation (HI) is performed following open endotracheal suctioning (OES), whose goals include: to stimulate a cough, recover oxygenation and improve compliance. However, it may also induce unintended consequences, including: lung stress and strain, failure to maintain high distending pressure, and subsequently cycling recruitment and derecruitment. Here, our aim was to investigate the effects of hyperinflation after repeated OES on sequential alteration of arterial oxygenation and lung injury profile using a saline lavage-induced surfactant depleted ARDS rabbit model.MethodsBriefly, 30 Japanese White Rabbits were anesthetized and ventilated in pressure-controlled setting with a tidal volume of 6-8 ml/kg. Animals were divided into four groups, i.e.; Control, ARDS, OES, and HI. Saline-lavage-induced lung injury was induced except for Control group. Thereafter, rabbits were ventilated with positive-end expiratory pressure (PEEP) at 10 cm H2O. The ARDS group received ventilation with the same PEEP without derecruitment. As intervention, OES and HI were performed in ARDS animals. OES was performed for 15 seconds at 150 mm Hg, whereas HI was performed with PEEP at 0 cm H2O and peak inspiratory pressure at +5 cm H2O for a minute. Total duration of the experiment was for 3 hours. OES and HI were performed every 15 minutes from beginning of the protocol.ResultsPaO2 was maintained at about 400 mm Hg in both control and ARDS groups for the duration of this study, while in both OES and HI groups, PaO2 decreased continuously up to 3 hours, dropped to a mean (±SD) of 226 ± 28.9 and 97.0 ± 30.7 mmHg at 3 h, respectively. HI group had the lowest PaO2 in the present investigation. Histological lung injury score was the highest in HI group than other three groups. Pulmonary TNF-α and IL-8 levels were the highest in HI group compared to other groups, but without significant alterations at circulatory level in all the experimental groups.ConclusionsWe show in the present study that hyperinflation following repeated OES deteriorate arterial oxygenation and the severity of lung injury in a rabbit model of ARDS undergoing mechanical ventilation