BackgroundAn uncontrolled inflammatory response is a critical pathophysiological feature of sepsis. Mesenchymal stem cells (MSCs) induce macrophage phenotype polarization and reduce inflammation in sepsis. MSC-secreted transforming growth factor beta (TGF-β) participated in the immune modulatory function of MSCs. However, the underlying mechanism of MSC-secreted TGF-β was not fully elucidated in regulation macrophage M2-like polarization.MethodsThe paracrine effects of MSCs on macrophage polarization were studied using a co-culture protocol with LPS-stimulated RAW264.7 cells/mouse peritoneal macrophages and MSCs. The effect of TGF-β in the co-culture system was blocked by the TGF-β receptor inhibitor. To determine the role of MSC-secreted TGF-β, we used recombinant TGF-β to culture with LPS-stimulated RAW264.7 cells. In addition, we employed antibody microarray analysis to determine the mechanisms of MSC secreted TGF-β on LPS-stimulated RAW264.7 cell/mouse peritoneal macrophage M2-like polarization. Furthermore, we used an Akt inhibitor and a FoxO1 inhibitor to inhibit the Akt/FoxO1 pathway. The nuclear translocation of FoxO1 was detected by Western blot.ResultsMSCs induced LPS-stimulated RAW264.7 cell/mouse peritoneal macrophage polarization towards the M2-like phenotype and significantly reduced pro-inflammatory cytokine levels via paracrine, which was inhibited by TGF-β receptor inhibitor. Furthermore, we found that MSC-secreted TGF-β enhanced the macrophage phagocytic ability. The antibody microarray analysis and Western blot verified that TGF-β treatment activated the Akt/FoxO1 pathway in LPS-stimulated macrophages, TGF-β-induced FoxO1 nuclear translocation and obviously expressed in the cytoplasm, the effects of TGF-β regulatory effects on LPS-stimulated macrophage were inhibited by pre-treatment with Akt inhibitor and FoxO1 inhibitor.ConclusionsTGF-β secreted by MSCs could skew LPS-stimulated macrophage polarization towards the M2-like phenotype, reduce inflammatory reactions, and improve the phagocytic ability via the Akt/FoxO1 pathway, providing potential therapeutic strategies for sepsis.
Background: This hypothesis-generating trial evaluated neoadjuvant ipatasertib-paclitaxel for early triple-negative breast cancer (TNBC).Patients and methods: In this randomized phase II trial, patients with early TNBC (T ! 1.5 cm, N0-2) were randomized 1 : 1 to receive weekly paclitaxel 80 mg/m 2 with ipatasertib 400 mg or placebo (days 1-21 every 28 days) for 12 weeks before surgery. Co-primary end points were pathologic complete response (pCR) rate (ypT0/TisN0) in the intention-to-treat (ITT) and immunohistochemistry phosphatase and tensin homolog (PTEN)-low populations. Secondary end points included pCR rate in patients with PIK3CA/AKT1/PTEN-altered tumors and pre-surgery response rates by magnetic resonance imaging (MRI).Results: pCR rates with ipatasertib versus placebo were 17% versus 13%, respectively, in the ITT population (N ¼ 151), 16% versus 13% in the immunohistochemistry PTEN-low population (N ¼ 35), and 18% versus 12% in the PIK3CA/AKT1/PTEN-altered subgroup (N ¼ 62). Rates of overall and complete response (CR) by MRI favored ipatasertib in all three populations (CR rate 39% versus 9% in the PIK3CA/AKT1/PTEN-altered subgroup). Ipatasertib was associated with more grade !3 adverse events (32% versus 16% with placebo), especially diarrhea (17% versus 1%). Higher cycle 1 day 8 (C1D8) immune score was significantly associated with better response only in placebo-treated patients. All ipatasertib-treated patients with low immune scores and a CR had PIK3CA/AKT1/PTEN-altered tumors.Conclusions: Adding ipatasertib to 12 weeks of paclitaxel for early TNBC did not clinically or statistically significantly increase pCR rate, although overall response rate by MRI was numerically higher with ipatasertib. The antitumor effect of ipatasertib was most pronounced in biomarker-selected patients. Safety was consistent with prior experience of ipatasertib-paclitaxel. A T-cellrich environment at C1D8 had a stronger association with improved outcomes in paclitaxel-treated patients than seen for baseline tumor-infiltrating lymphocytes. This dependency may be overcome with the addition of AKT inhibition, especially in patients with PIK3CA/AKT1/PTEN-altered tumors. ClinicalTrials.gov: NCT02301988.
[with no lysine (k)] kinase is a serine/threonine kinase subfamily. Mutations in two of the WNK kinases result in pseudohypoaldosteronism type II (PHA II) characterized by hypertension, hyperkalemia, and metabolic acidosis. Recent studies showed that both WNK1 and WNK4 inhibit ROMK activity. However, little is known about the effect of WNK kinases on Maxi K, a large-conductance Ca 2ϩ and voltage-activated potassium (K) channel. Here, we report that WNK4 wild-type (WT) significantly inhibits Maxi K channel activity in HEK ␣BK stable cell lines compared with the control group. However, a WNK4 dead-kinase mutant, D321A, has no inhibitory effect on Maxi K activity. We further found that WNK4 inhibits total and cell surface protein expression of Maxi K equally compared with control groups. A dominant-negative dynamin mutant, K44A, did not alter the WNK4-mediated inhibitory effect on Maxi K surface expression. Treatment with bafilomycin A1 (a proton pump inhibitor) and leupeptin (a lysosomal inhibitor) reversed WNK4 WT-mediated inhibition of Maxi K total protein expression. These findings suggest that WNK4 WT inhibits Maxi K activity by reducing Maxi K protein at the membrane, but that the inhibition is not due to an increase in clathrin-mediated endocytosis of Maxi K, but likely due to enhancing its lysosomal degradation. Also, WNK4's inhibitory effect on Maxi K activity is dependent on its kinase activity. protein expression; lysosomal degradation WNK [WITH NO LYSINE (K)] KINASE belongs to a subfamily of serine/threonine kinases (55). Mutations in two members of this family, WNK1 and WNK4, result in pseudohypoaldosteronism type II (PHA II). PHA II, also referred to as Gordon's syndrome, is an autosomal dominant disorder, characterized by hypertension, hyperkalemia, and metabolic acidosis (51). This clinical phenotype suggests that WNK kinases might regulate renal potassium (K) channels, such as renal outer medullary potassium channel (ROMK) or Maxi K channels (BK channels) that are responsible for K handling by the distal nephron. A number of studies indicate that WNK kinases constitute a novel signaling pathway that is involved in the regulation of different ion transporters and channels controlling sodium and K homeostasis (23). In kidney tissue, there are two types of apical K channels identified in the distal nephron by patchclamp analysis (38). One type of K channel is a low-conductance secretory K (SK) channel that has high open probability at resting membrane potential and mediates K ϩ secretion under basal conditions. The properties of the SK channel are consistent with those of ROMK. The other type of K channel has a high single-channel conductance (Ͼ100 pS) and channel kinetics similar to Maxi K channels (34). Although it is generally accepted that ROMK is the K ϩ secretory channel in the mammalian distal nephron, recent in vitro and in vivo studies have provided evidence that Maxi K can also serves as a K ϩ secretory channel in renal tubules (37) and that it plays an important role in K ϩ secretion in ROM...
Clostridium beijerinckii is an anaerobic bacterium used for the fermentative production of acetone and butanol. The recent availability of genomic sequence information for C. beijerinckii NCIMB 8052 has allowed for an examination of gene expression during the shift from acidogenesis to solventogenesis over the time course of a batch fermentation using a ca. 500-gene set DNA microarray. The microarray was constructed using a collection of genes which are orthologs of members of gene families previously found to be important to the physiology of C. acetobutylicum ATCC 824. Similar to the onset of solventogenesis in C. acetobutylicum 824, the onset of solventogenesis in C. beijerinckii 8052 was concurrent with the initiation of sporulation. However, forespores and endospores developed more rapidly in C. beijerinckii 8052 than in C. acetobutylicum 824, consistent with the accelerated expression of the sigE-and sigG-regulated genes in C. beijerinckii 8052. The comparison of gene expression patterns and morphological changes in C. beijerinckii 8052 and the hyperbutanol-producing C. beijerinckii strain BA101 indicated that BA101 was less efficient in sporulation and phosphotransferase system-mediated sugar transport than 8052 but that it exhibited elevated expression of several primary metabolic genes and chemotaxis/motility genes.The gram-positive, spore-forming, anaerobic clostridia constitute a diverse group of species with industrial, agricultural, and medical relevance. Clostridium acetobutylicum and C. beijerinckii are among the prominent solventogenic species capable of acetone and butanol formation via fermentation (8,15). Butanol is widely used as an industrial chemical. Butanol also exhibits a range of physical properties, including high energy content, water immiscibility, low vapor pressure, and octaneenhancing power, which provide it with potential as a liquid fuel (17). Developing fermentation processes based on the solventogenic clostridia offers the prospect of butanol production from agricultural feedstocks as an alternative to the petrochemical route (8). Much of past efforts has been focused on C. acetobutylicum ATCC 824 (1,16,23). However, the functional characterization of genes and metabolic pathways remains to be undertaken. Recently, genome sequencing of C. beijerinckii NCIMB 8052 was completed by the Joint Genome Institute of the Department of Energy. This accomplishment opens up the exciting possibility of investigating the molecular mechanism of solventogenesis on a genome scale. The objective of this study involves using DNA microarray analysis to examine gene expression in relation to physiological changes associated with C. beijerinckii solvent production and cell growth and differentiation. The comparison of gene expression patterns in the C. beijerinckii 8052 parental strain and the C. beijerinckii BA101 hyper-butanol-producing mutant strain (3, 11) will provide insights toward engineering genetically modified C. beijerinckii strains with improved butanol yields, titers, and productivity...
On average, each human gene has approximately four SNPs (single nucleotide polymorphisms) in the coding region, half of which are nsSNPs (non-synonymous SNPs) or missense SNPs. Current attention is focused on those that are known to perturb function and are strongly linked to disease. However, the vast majority of SNPs have not been investigated for the possibility of causing disease. We set out to assess the fraction of nsSNPs that encode proteins that have altered stability and activity, for this class of variants would be candidates to perturb cellular function. We tested the thermostability and, where possible, the catalytic activity for the most common variant (wild-type) and minor variants (total of 46 SNPs) for 16 human enzymes for which the three-dimensional structures were known. There were significant differences in the stability of almost half of the variants (48%) compared with their wild-type counterparts. The catalytic efficiency of approx. 14 variants was significantly altered, including several variants of human PKM2 (pyruvate kinase muscle 2). Two PKM2 variants, S437Y and E28K, also exhibited changes in their allosteric regulation compared with the wild-type enzyme. The high proportion of nsSNPs that affect protein stability and function, albeit subtly, underscores the need for experimental analysis of the diverse human proteome.
With no lysine (WNK) kinases are members of the serine/threonine kinase family. We previously showed that WNK4 inhibits renal large-conductance Ca 2+ -activated K + (BK) channel activity by enhancing its degradation through a lysosomal pathway. In this study, we investigated the effect of WNK1 on BK channel activity. In HEK293 cells stably expressing the a subunit of BK (HEK-BKa cells), siRNA-mediated knockdown of WNK1 expression significantly inhibited both BKa channel activity and open probability. Knockdown of WNK1 expression also significantly inhibited BKa protein expression and increased ERK1/2 phosphorylation, whereas overexpression of WNK1 significantly enhanced BKa expression and decreased ERK1/2 phosphorylation in a dose-dependent manner in HEK293 cells. Knockdown of ERK1/2 prevented WNK1 siRNA-mediated inhibition of BKa expression. Similarly, pretreatment of HEK-BKa cells with the lysosomal inhibitor bafilomycin A1 reversed the inhibitory effects of WNK1 siRNA on BKa expression in a dose-dependent manner. Knockdown of WNK1 expression also increased the ubiquitination of BKa channels. Notably, mice fed a high-K + diet for 10 days had significantly higher renal protein expression levels of BKa and WNK1 and lower levels of ERK1/2 phosphorylation compared with mice fed a normal-K + diet. These data suggest that WNK1 enhances BK channel function by reducing ERK1/2 signaling-mediated lysosomal degradation of the channel. With no lysine (WNK) kinase belongs to a family of serine/threonine kinases. Mutations of WNK1 and WNK4 are responsible for pseudohypoaldosteronism type II (PHAІІ), characterized by hypertension, hyperkalemia, and metabolic acidosis. 1,2 The disease mutation in WNK1 or WNK4 kinase resulting in hyperkalemia suggests a role of WNK in potassium handling in renal distal nephron, which contains two major potassium channels, renal outer medullary K + channels (ROMK) and Big K (BK) channels. 3,4 WNK4 inhibits ROMK channel activity and its surface expression, whereas WNK4 disease mutant enhances its inhibitory effect on ROMK. 5 WNK1 also inhibits ROMK activity; however, a kidney-specific form of WNK1 (KS-WNK1) reverses WNK1's effect on ROMK. 6 WNK4 inhibits BK channel activity and protein expression, 7-9 whereas WNK4 disease mutant also enhances its inhibitory effect on BK activity via a ubiquitin-dependent pathway. 9 BK channel (or Maxi K) is a large conductance Ca 2+ and voltage-activated K channel. 10 BK is encoded by the gene slo1 11 and is widely distributed in many different
A number of large scale cancer somatic genome sequencing projects are now identifying genetic alterations in cancers. Evaluation of the effects of these mutations is essential for understanding their contribution to tumorigenesis. We have used SNPs3D, a software suite originally developed for analyzing non-synonymous germ line variants, to identify single base mutations with a high impact on protein structure and function. Two machine learning methods are used, one identifying mutations that destabilize protein three dimensional structure, and the other utilizing sequence conservation, and detecting all types of effects on in vivo protein function. Incorporation of detailed structure information into the analysis allows detailed interpretation of the functional effects of mutations in specific cases. Data from a set of breast and colorectal tumors were analyzed. In known cancer genes, approaching 100% of mutations are found to impact protein function, supporting the view that these methods are appropriate for identifying driver mutations. Overall, 50% to 60% of all somatic missense mutations are predicted to have a high impact on structural stability or to more generally affect the function of the corresponding proteins. This value is similar to the fraction of all possible missense mutations that have high impact, and much higher than the corresponding one for human population SNPs, at about 30%. The majority of mutations in tumor suppressors destabilize protein structure, while mutations in oncogenes operate in more varied ways, including destabilization of the less active conformational states. The set of high impact mutations encompass the possible drivers.
Our findings revealed that compared with surgery alone, neoadjuvant chemoradiotherapy was associated with improved 1-, 3- and 5-year survival times, but not associated with increased postoperative morbidity and mortality in patients with esophageal carcinoma.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.