Background and Purpose
Mitochondrial dysfunction plays a role in the progression of cardiovascular diseases including heart failure. 3‐Hydroxy‐3‐methylglutaryl‐CoA reductase inhibitors (statins), ...which inhibit ROS synthesis, show cardioprotective effects in chronic heart failure. However, the beneficial role of statins in mitochondrial protection in heart failure remains unclear.
Experimental Approach
Rats were treated with angiotensin II (1.5 mg·kg−1·day−1) or co‐administered simvastatin (oral, 10 mg·kg−1) for 14 days; and then administration was stopped for the following 14 days. Cardiac structure/function was examined by wheat germ agglutinin staining and echocardiography. Mitochondrial morphology and the numbers of lipid droplets, lysosomes, autophagosomes, and mitophagosomes were determined by transmission electron microscopy. Human cardiomyocytes were stimulated, and intracellular ROS and mitochondrial membrane potential (ΔΨm) changes were measured by flow cytometry and JC‐1 staining, respectively. Autophagy and mitophagy‐related and mitochondria‐regulated apoptotic proteins were identified by immunohistochemistry and western blotting.
Key Results
Simvastatin significantly reduced ROS production and attenuated the disruption of ΔΨm. Simvastatin induced the accumulation of lipid droplets to provide energy for maintaining mitochondrial function, promoted autophagy and mitophagy, and inhibited mitochondria‐mediated apoptosis. These findings suggest that mitochondrial protection mediated by simvastatin plays a therapeutic role in heart failure prevention by modulating antioxidant status and promoting energy supplies for autophagy and mitophagy to inhibit mitochondrial damage and cardiomyocyte apoptosis.
Conclusion and Implications
Mitochondria play a key role in mediating heart failure progression. Simvastatin attenuated heart failure, induced by angiotensin II, via mitochondrial protection and might provide a new therapy to prevent heart failure.
Exosomes are implicated in cancer cell development, migration and invasion. Pigment epithelium-derived factor (PEDF) is a secreted anticancer protein that can regulate lung cancer progression; ...however, the role of PEDF in non-small cell lung cancer (NSCLC), including metastasis and cancer cell-derived exosome secretion, is unclear. In this study, we analyzed the effects of PEDF on exosome-mediated migration, invasion, and tumorigenicity of cultured NSCLC cells. The results showed that PEDF overexpression significantly reduced NSCLC invasion and migration, while inducing cell aggregation, whereas PEDF knockdown had the opposite effects. Exosomes from NSCLC cells treated with recombinant PEDF had a significantly reduced ability to promote cancer cell motility, migration, and invasion compared to exosomes from untreated cells. Exosomes from PEDF-treated cells contained thrombospondin 1 (THBS1), which inhibited cytoskeletal remodeling and exosome-induced lung cancer cell motility, migration, and invasion. Furthermore, PEDF-overexpressing NSCLC cells formed smaller xenograft tumors with higher THBS1 expression compared to control tumors. Our findings indicate that PEDF decreases the metastatic potential of NSCLC cells through regulation of THBS1 release in cancer cell-derived exosomes, thus uncovering a new mechanism of lung cancer progression.
•PEDF induces aggregation and reduces invasion and migration of lung cancer cells.•Exosomes from PEDF-treated cancer cells inhibit metastatic behavior of NSCLC cells.•PEDF-expressing NSCLC cells have reduced tumorigenicity in vivo.•PEDF increases thrombospondin 1 content in lung cancer cell-derived exosomes.•Thrombospondin 1 inhibits exosome-induced lung cancer cell migration and invasion.
MicroRNA399-mediated regulation of the ubiquitin-conjugating enzyme UBC24/PHOSPHATE2 (PHO2) is crucial for Pi acquisition and translocation in plants. Because of a potential role for PHO2 in protein ...degradation and its association with membranes, an iTRAQ (for isobaric tags for relative and absolute quantitation)- based quantitative membrane proteomic method was employed to search for components downstream of PHO2. A total of 7491 proteins were identified from Arabidopsis thaliana roots by mass spectrometry, 35.2% of which were predicted to contain at least one transmembrane helix. Among the quantifiable proteins, five were significantly differentially expressed between the wild type and pho2 mutant under two growth conditions. Using immunoblot analysis, we validated the upregulation of several members in PHOSPHATE TRANSPORTER1 (PHT1) family and PHOSPHATE TRANSPORTER TRAFFIC FACILITATOR1 (PHF1) in pho2 and demonstrated that PHO2 mediates the degradation of PHT1 proteins. Genetic evidence that loss of PHF1 or PHT1;1 alleviated Pi toxicity in pho2 further suggests that they play roles as downstream components of PHO2. Moreover, we showed that PHO2 interacts with PHT1s in the postendoplasmic reticulum compartments and mediates the ubiquitination of endomembrane-localized PHT1;1. This study not only uncovers a mechanism by which PHO2 modulates Pi acquisition by regulating the abundance of PHT1s in the secretory pathway destined for plasma membranes, but also provides a database of the membrane proteome that will be widely applicable in root biology research.
Background & Aims
Differentiation antagonizing non‐protein coding RNA is associated with various types of neoplasms. Hepatitis C virus‐related hepatocellular carcinoma has a high risk of recurrence. ...Here we determined the role of differentiation antagonizing non‐protein coding RNA in hepatitis C virus‐related hepatocarcinogenesis and identified potential therapeutic targets and non‐invasive prognostic markers for long‐term outcome of hepatitis C virus‐related hepatocellular carcinoma after surgical resection.
Methods
Differentiation antagonizing non‐protein coding RNAs relevant to hepatitis C virus‐related hepatocellular carcinoma were identified through comparative RNA‐sequencing of tumour and adjacent non‐tumour (ANT) tissues in a screening set, and were validated using real‐time polymerase chain reaction. Target long non‐coding RNAs (lncRNAs) in tissues and serum exosomes were used to predict the recurrence of hepatitis C virus‐related hepatocellular carcinoma after curative surgical resection in a large application cohort from 2005 to 2012.
Results
We confirmed that differentiation antagonizing non‐protein coding RNA was upregulated following hepatitis C virus infection and identified as the lncRNA most relevant to hepatitis C virus‐related hepatocellular carcinoma in tumour tissues as compared to that in ANT tissues. In 183 hepatitis C virus‐related hepatocellular carcinoma patients followed for 10 years after curative HCC resection, the expression level of circulating exosomal differentiation antagonizing non‐protein coding RNA was positively associated with HCC recurrence and was the most predictive factor associated with HCC recurrence and mortality (hazard ratio/95% confidence intervals: 7.0/4.3‐11.6 and 2.7/1.5‐5.1 respectively).
Conclusions
Differentiation antagonizing non‐protein coding RNA is highly relevant to disease progression of hepatitis C virus‐related hepatocellular carcinoma. Our finding indicated that circulating exosomal differentiation antagonizing non‐protein coding RNA might serve as a non‐invasive prognostic biomarker for hepatitis C virus‐related hepatocellular carcinoma.
Metformin has been reported to possess antitumor activity and maintain high cytotoxic T lymphocyte (CTL) immune surveillance. However, the functions and detailed mechanisms of metformin’s role in ...cancer immunity are not fully understood. Here, we show that metformin increases CTL activity by reducing the stability and membrane localization of programmed death ligand-1 (PD-L1). Furthermore, we discover that AMP-activated protein kinase (AMPK) activated by metformin directly phosphorylates S195 of PD-L1. S195 phosphorylation induces abnormal PD-L1 glycosylation, resulting in its ER accumulation and ER-associated protein degradation (ERAD). Consistently, tumor tissues from metformin-treated breast cancer patients exhibit reduced PD-L1 levels with AMPK activation. Blocking the inhibitory signal of PD-L1 by metformin enhances CTL activity against cancer cells. Our findings identify a new regulatory mechanism of PD-L1 expression through the ERAD pathway and suggest that the metformin-CTLA4 blockade combination has the potential to increase the efficacy of immunotherapy.
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•Metformin enhances antitumor CTL immunity by blocking PD-L1/PD-1 axis•Metformin-activated AMPK directly binds to and phosphorylates PD-L1 at S195•Abnormal PD-L1 glycosylation induced by pS195 leads to PD-L1 degradation by ERAD•Combination therapy with metformin and anti-CTLA4 has a synergistic antitumor effect
Cha et al. elucidated a mechanism to show that metformin-activated AMPK phosphorylates PD-L1 at S195 to induce abnormal glycosylation and degrades PD-L1 through an ERAD pathway. This study suggests the potential to use metformin as an adjuvant with various non-PD-L1/PD-1-targeting immune therapies.
Corylin is a main compound isolated from Psoralea corylifolia L. (Fabaceae). A variety of pharmacological effects such as antioxidant, anti-proliferation, and anti-inflammatory properties of corylin ...have been reported. Nevertheless, the effect of corylin in microbial infection and sepsis remains unclear. In the present study, we investigated the anti-inflammatory effects of corylin. Our experimental results demonstrated that corylin inhibited the production of TNF-α, IL-6 and NO by both LPS-activated RAW 264.7 cells and LPS-activated murine peritoneal macrophages. Moreover, corylin suppressed the expression levels of iNOS and COX-2, reduced the production of PGE
and HMGB1, blocked the translocation of HMGB1 from the nucleus to cytosol, and decreased the phosphorylation of MAPKs in LPS-activated RAW 264.7 cells as well as suppressed the activity of NF-κB in LPS-activated J-Blue cells. In addition, the administration of corylin reduced the production of NO and TNF-α, decreased LPS-induced liver damage markers (AST and ALT) and kidney damage markers (BUN and CRE), attenuated infiltration of inflammatory cells and tissue damage of lung, liver and kidney, and enhanced the survival rate of LPS-challenged mice. Taken together, these results show the anti-inflammatory properties of corylin on LPS-induced inflammation and sepsis. Corylin could potentially be a novel anti-inflammatory and immunosuppressive drug candidate in the treatment of sepsis and septic shock.
Opioid-overdose deaths are associated with poisoning with prescription and illicit opioids in the USA. In contrast, opioid-related deaths (ORDs) in the UK often involve drugs and substances of ...misuse, and may not be associated with a high dose of prescribed opioids. This study aimed to investigate the association between prescribed opioid dose and ORDs in UK primary care.
This case-crossover study used the Clinical Practice Research Datalink and death registration between 2000 and 2015 to identify ORDs. Daily oral morphine equivalent (OMEQ) dose was measured within a 90 day focal window before ORD and three earlier reference windows. Conditional logistic regression models assessed the adjusted odds ratio (aOR) and 95% confidence interval (95% CI) comparing daily OMEQ dose greater than 120 mg in the focal window against the reference windows.
Of the 232 ORDs, 62 (26.7%) were not prescribed opioids in the year before death. Of the remaining 170 cases, 50 (29.4%) were never prescribed a daily OMEQ dose greater than 50 mg. Daily OMEQ doses over 120 mg (aOR 2.20; 95% CI: 1.06–4.56), co-prescribing gabapentinoids (aOR 2.32; 95% CI: 1.01–5.33), or some antidepressants (aOR 3.03; 95% CI: 1.02–9.04) significantly increased the risk of ORD.
Daily OMEQ dose greater than 120 mg and the concomitant use of psychotropic medicines were related to ORDs in the UK. Prescribers should cautiously avoid prescribing opioids with a daily OMEQ dose greater than 120 mg day−1 and the combination of opioids and gabapentinoids, even with low opioid doses.
Metaplastic breast carcinoma (MpBC) typically consists of carcinoma of no special type (NST) with various metaplastic components. Although previous transcriptomic and proteomic studies have reported ...subtype-related heterogeneity, the intracase transcriptomic alterations between metaplastic components and paired NST components, which are critical for understanding the pathogenesis underlying the metaplastic processes, remain unclear.
Fifty-nine NST components and paired metaplastic components (spindle carcinomatous SPS, matrix-producing, rhabdoid RHA, and squamous carcinomatous SQC components) were microdissected from specimens obtained from 27 patients with MpBC for gene expression profiling using the NanoString Breast Cancer 360 Panel on a NanoString nCounter FLEX platform. BC360-defined signatures were scored using nSolver software.
Hierarchical clustering and principal component analysis revealed a heterogeneous gene expression profile (GEP) corresponding to the NST components, but the GEP of metaplastic components exhibited subtype dependence. Compared with the paired NST components, the SPS components demonstrated the upregulation of genes related to stem cells and epithelial-mesenchymal transition and displayed enrichment in claudin-low and macrophage signatures. Despite certain overlaps in the enriched functions and signatures between the RHA and SPS components, the specific differentially expressed genes differed. We observed the RHA-specific upregulation of genes associated with vascular endothelial growth factor signaling. The chondroid matrix-producing components demonstrated the upregulation of hypoxia-related genes and the downregulation of the immune-related MHC2 signature and the TIGIT gene. In the SQC components, TGF-β and genes associated with cell adhesion were upregulated. The differentially expressed genes among metaplastic components in the 22 MpBC cases with one or predominantly one metaplastic component clustered paired NST samples into clusters with correlation with their associated metaplastic types. These genes could be used to separate the 31 metaplastic components according to respective metaplastic types with an accuracy of 74.2%, suggesting that intrinsic signatures of NST may determine paired metaplastic type. Finally, the EMT activity and stem cell traits in the NST components were correlated with specimens displaying lymph node metastasis.
We presented the distinct transcriptomic alterations underlying metaplasia into specific metaplastic components in MpBCs, which contributes to the understanding of the pathogenesis underlying morphologically distinct metaplasia in MpBCs.
Most cases of oral squamous cell carcinoma (OSCC) develop from visible oral potentially malignant disorders (OPMDs). The latter exhibit heterogeneous subtypes with different transformation ...potentials, complicating the early detection of OSCC during routine visual oral cancer screenings. To develop clinically applicable biomarkers, we collected saliva samples from 96 healthy controls, 103 low-risk OPMDs, 130 high-risk OPMDs, and 131 OSCC subjects. These individuals were enrolled in Taiwan’s Oral Cancer Screening Program. We identified 302 protein biomarkers reported in the literature and/or through in-house studies and prioritized 49 proteins for quantification in the saliva samples using multiple reaction monitoring-MS. Twenty-eight proteins were successfully quantified with high confidence. The quantification data from non-OSCC subjects (healthy controls + low-risk OPMDs) and OSCC subjects in the training set were subjected to classification and regression tree analyses, through which we generated a four-protein panel consisting of MMP1, KNG1, ANXA2, and HSPA5. A risk-score scheme was established, and the panel showed high sensitivity (87.5%) and specificity (80.5%) in the test set to distinguish OSCC samples from non-OSCC samples. The risk score >0.4 detected 84% (42/50) of the stage I OSCCs and a significant portion (42%) of the high-risk OPMDs. Moreover, among 88 high-risk OPMD patients with available follow-up results, 18 developed OSCC within 5 y; of them, 77.8% (14/18) had risk scores >0.4. Our four-protein panel may therefore offer a clinically effective tool for detecting OSCC and monitoring high-risk OPMDs through a readily available biofluid.
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