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Cell Death & Disease Jun 2024High basal autophagy and enhanced mitochondrial fission in triple-negative breast cancer (TNBC) cells support cell migration and promote plasticity of cancer cell...
High basal autophagy and enhanced mitochondrial fission in triple-negative breast cancer (TNBC) cells support cell migration and promote plasticity of cancer cell metabolism. Here, we suggest a novel combination therapy approach for the treatment of TNBC that targets Drp1-mediated mitochondrial fission and autophagy pathways. Hydrogen sulfide (HS) mediates a myriad of biological processes, including autophagy and mitochondrial function. In this study, we demonstrated that 5-(4-hydroxyphenyl)-3H-1,2-dithiole-3-thione (ADT-OH), one of the most widely utilized sustained-release HS donors, effectively suppresses metastasis of TNBC cells in the absence of proliferation inhibition in vitro and in vivo. ADT-OH treatment ameliorated autophagy flux by suppressing autophagosome formation and induced mitochondrial elongation through decreasing expression of dynamin-related protein 1 (Drp1) and increasing expression of mitochondrial fusion protein (Mfn2). At the same time, ADT-OH downregulated mitophagy flux and inhibited mitochondrial function, eventually leading to the inhibition of migration and invasion in TNBC cells. In vivo, intraperitoneal administration of ADT-OH revealed a potent anti-metastatic activity in three different animal models, the MDA-MB-231 orthotopic xenograft model, the 4T1-Luci orthotopic model and the 4T1-Luci tail vein metastasis model. However, ADT-OH has an extremely low water solubility, which is a significant barrier to its effectiveness. Thus, we demonstrated that the solubility of ADT-OH in water can be improved significantly by absorption with hydroxypropyl-β-cyclodextrin (CD). Remarkably, the obtained CD-ADT-OH demonstrated superior anti-cancer effect to ADT-OH in vivo. Altogether, this study describes a novel regulator of mammalian mitochondrial fission and autophagy, with potential utility as an experimental therapeutic agent for metastatic TNBC.
Topics: Triple Negative Breast Neoplasms; Mitochondrial Dynamics; Humans; Animals; Autophagy; Female; Cell Line, Tumor; Mice; Cell Movement; Mice, Nude; Thiones; Xenograft Model Antitumor Assays; Mice, Inbred BALB C; Mitochondria; Cell Proliferation; Neoplasm Metastasis; Hydrogen Sulfide; Dynamins; Thiophenes
PubMed: 38942765
DOI: 10.1038/s41419-024-06829-w -
Biomedicine & Pharmacotherapy =... Jun 2024Melanoma cells express high levels of CD73 that produce extracellular immunosuppressive adenosine. Changes in the CD73 expression occur in response to tumor...
Melanoma cells express high levels of CD73 that produce extracellular immunosuppressive adenosine. Changes in the CD73 expression occur in response to tumor environmental factors, contributing to tumor phenotype plasticity and therapeutic resistance. Previously, we have observed that CD73 expression can be up-regulated on the surface of melanoma cells in response to nutritional stress. Here, we explore the mechanism by which melanoma cells release soluble CD73 under low nutrient availability and whether this might be affected by agents targeting the proto-oncogene B-Raf (BRAF). We found that starved melanoma cells can release high levels of CD73, able to convert AMP into adenosine, and this activity is abrogated by selective CD73 inhibitors, APCP or PSB-12489. The release of CD73 from melanoma cells is mediated by the matrix metalloproteinase MMP-9. Indeed, MMP-9 inhibitors significantly reduce the levels of CD73 released from the cells, while its surface levels increase. Of relevance, melanoma cells, harboring an activating BRAF mutation, upon treatment with dabrafenib or vemurafenib, show a strong reduction of CD73 cell expression and reduced levels of CD73 released into the extracellular space. Conversely, melanoma cells resistant to dabrafenib show high expression of membrane-bound CD73 and soluble CD73 released into the culture medium. In summary, our data indicate that CD73 is released from melanoma cells. The expression of CD73 is associated with response to BRAF inhibitors. Melanoma cells developing resistance to dabrafenib show increased expression of CD73, including soluble CD73 released from cells, suggesting that CD73 is involved in acquiring resistance to treatment.
PubMed: 38941889
DOI: 10.1016/j.biopha.2024.117033 -
Science Advances Jun 2024The nanoscale morphology of the photoactive layer notably impacts the performance of organic solar cells (OSCs). Conventional methods to tune the morphology are...
The nanoscale morphology of the photoactive layer notably impacts the performance of organic solar cells (OSCs). Conventional methods to tune the morphology are typically chemical approaches that adjust the properties (such as solubility and miscibility) of the active components including donor, acceptor, and/or additive. Here, we demonstrate a completely different approach by applying an external electric field (EEF) on the active layer during the wet coating. The EEF-coating method is perfectly compatible with an ambient blade coating using environmentally friendly solvents, which are essential requirements for industrial production of OSCs. A record 18.6% efficiency is achieved using the EEF coating, which is the best value for open-air, blade-coated OSCs to date. Our findings suggest broad material applicability and attribute-enhanced performance to EEF-induced fiber formation and long-range ordering of microstructures of acceptor domains. This technique offers an effective method for producing high-performance OSCs, especially suited for industry OSC production based on open-air printing.
PubMed: 38941466
DOI: 10.1126/sciadv.ado5460 -
Medicine Jun 2024Acute pancreatitis (AP) is a common emergency condition with high morbidity, mortality, and socio-economic impact. Soluble urokinase plasminogen activator receptor...
BACKGROUND
Acute pancreatitis (AP) is a common emergency condition with high morbidity, mortality, and socio-economic impact. Soluble urokinase plasminogen activator receptor (suPAR) is a potential biomarker for AP prognosis. This study systematically reviews the literature on suPAR's prognostic roles in assessing AP severity, organ failure, mortality, and other pathological markers.
METHODS
A comprehensive search of 5 databases up to March 19, 2023, was conducted, selecting cohort studies that examined suPAR's relationship with AP outcomes. Outcome variables included AP severity, organ failure, mortality, hospital stay length, and suPAR's association with other inflammatory markers. Our paper has been registered on Prospero (ID: CRD42023410628).
RESULTS
Nine prospective observational studies with 1033 AP patients were included. Seven of eight studies found suPAR significantly elevated in severe acute pancreatitis (P < .05). Four studies showed suPAR effectively predicted organ failure risk, and 4 studies concluded suPAR significantly predicted mortality (P < .05). The review had no high-risk studies, enhancing credibility.
CONCLUSION
suPAR is a valuable prognostic marker in AP, significantly predicting severity, organ failure, hospital stay length, and mortality. Further large-scale studies are needed to explore suPAR's role in other clinical outcomes related to AP disease course, to establish it as a mainstay of AP prognosis.
Topics: Humans; Pancreatitis; Receptors, Urokinase Plasminogen Activator; Prognosis; Biomarkers; Systematic Reviews as Topic; Severity of Illness Index; Length of Stay; Acute Disease
PubMed: 38941433
DOI: 10.1097/MD.0000000000037064 -
MBio Jun 2024Conjugative type 4 secretion systems (T4SSs) are the main driver for the spread of antibiotic resistance genes and virulence factors in bacteria. To deliver the DNA...
Conjugative type 4 secretion systems (T4SSs) are the main driver for the spread of antibiotic resistance genes and virulence factors in bacteria. To deliver the DNA substrate to recipient cells, it must cross the cell envelopes of both donor and recipient bacteria. In the T4SS from the enterococcal conjugative plasmid pCF10, PrgK is known to be the active cell wall degrading enzyme. It has three predicted extracellular hydrolase domains: metallo-peptidase (LytM), soluble lytic transglycosylase (SLT), and cysteine, histidine-dependent amidohydrolases/peptidases (CHAP). Here, we report the structure of the LytM domain and show that its active site is degenerate and lacks the active site metal. Furthermore, we show that only the predicted SLT domain is functional and that it unexpectedly has a muramidase instead of a lytic transglycosylase activity. While we did not observe any peptidoglycan hydrolytic activity for the LytM or CHAP domain, we found that these domains downregulated the SLT muramidase activity. The CHAP domain was also found to be involved in PrgK dimer formation. Furthermore, we show that PrgK interacts with PrgL, which likely targets PrgK to the rest of the T4SS. The presented data provides important information for understanding the function of Gram-positive T4SSs.IMPORTANCEAntibiotic resistance is a large threat to human health and is getting more prevalent. One of the major contributors to the spread of antibiotic resistance among different bacteria is type 4 secretion systems (T4SS). However, mainly T4SSs from Gram-negative bacteria have been studied in detail. T4SSs from Gram-positive bacteria, which stand for more than half of all hospital-acquired infections, are much less understood. The significance of our research is in identifying the function and regulation of a cell wall hydrolase, a key component of the pCF10 T4SS from . This system is one of the best-studied Gram-positive T4SSs, and this added knowledge aids in our understanding of horizontal gene transfer in as well as other medically relevant Gram-positive bacteria.
PubMed: 38940556
DOI: 10.1128/mbio.00488-24 -
Frontiers in Bioscience (Landmark... Jun 2024This study investigated the mechanism by which tazarotene-induced gene 1 (TIG1) inhibits melanoma cell growth. The main focus was to analyze downstream genes regulated...
BACKGROUND
This study investigated the mechanism by which tazarotene-induced gene 1 (TIG1) inhibits melanoma cell growth. The main focus was to analyze downstream genes regulated by TIG1 in melanoma cells and its impact on cell growth.
METHODS
The effects of TIG1 expression on cell viability and death were assessed using water-soluble tetrazolium 1 (WST-1) mitochondrial staining and lactate dehydrogenase release assays. RNA sequencing and Western blot analysis were employed to investigate the genes regulated by TIG1 in melanoma cells. Additionally, the correlation between expression and its downstream genes was analyzed in a melanoma tissue array.
RESULTS
TIG1 expression in melanoma cells was associated with decreased cell viability and increased cell death. RNA-sequencing (RNA-seq), quantitative reverse transcription PCR (reverse RT-QPCR), and immunoblots revealed that TIG1 expression induced the expression of Endoplasmic Reticulum (ER) stress response-related genes such as Homocysteine-responsive endoplasmic reticulum-resident ubiquitin-like domain member 1 (HERPUD1), Binding immunoglobulin protein (BIP), and DNA damage-inducible transcript 3 (DDIT3). Furthermore, analysis of the melanoma tissue array revealed a positive correlation between expression and the expression of , , and . Additionally, attenuation of the ER stress response in melanoma cells weakened the impact of TIG1 on cell growth.
CONCLUSIONS
TIG1 expression effectively hinders the growth of melanoma cells. TIG1 induces the upregulation of ER stress response-related genes, leading to an increase in caspase-3 activity and subsequent cell death. These findings suggest that the ability of retinoic acid to prevent melanoma formation may be associated with the anticancer effect of TIG1.
Topics: Humans; Endoplasmic Reticulum Stress; Melanoma; Cell Line, Tumor; Cell Survival; Gene Expression Regulation, Neoplastic; Cell Death; Apoptosis; Cell Proliferation; Membrane Proteins
PubMed: 38940043
DOI: 10.31083/j.fbl2906233 -
Frontiers in Bioscience (Landmark... Jun 2024This study investigated the impact of salvianolic acids, derived from Danshen, on melanoma cell growth. Specifically, we assessed the ability of salvianolic acid A (Sal...
BACKGROUND
This study investigated the impact of salvianolic acids, derived from Danshen, on melanoma cell growth. Specifically, we assessed the ability of salvianolic acid A (Sal A) to modulate melanoma cell proliferation.
METHODS
We used human melanoma A2058 and A375 cell lines to investigate the effects of Sal A on cell proliferation and death by measuring bromodeoxyuridine incorporation and lactate dehydrogenase release. We assessed cell viability and cycle progression using water soluble tetrazolium salt-1 (WST-1) mitochondrial staining and propidium iodide. Additionally, we used a phospho-kinase array to investigate intracellular kinase phosphorylation, specifically measuring the influence of Sal A on checkpoint kinase-2 (Chk-2) via western blot analysis.
RESULTS
Sal A inhibited the growth of A2058 and A375 cells dose-responsively and induced cell cycle arrest at the G2/M phase. Notably, Sal A selectively induces Chk-2 phosphorylation without affecting Chk-1, thereby degrading Chk-2-regulated genes and . However, Sal A does not affect the Chk1-Cdc25C pathway.
CONCLUSIONS
Salvianolic acids, especially Sal A, effectively hinder melanoma cell growth by inducing Chk-2 phosphorylation and disrupting G2/M checkpoint regulation.
Topics: Humans; Checkpoint Kinase 2; cdc25 Phosphatases; Melanoma; Cell Line, Tumor; Cell Proliferation; Lactates; Caffeic Acids; Signal Transduction; Phosphorylation; Cell Survival
PubMed: 38940031
DOI: 10.31083/j.fbl2906213 -
Frontiers in Bioscience (Elite Edition) Jun 2024Dextran is an exopolysaccharide synthesized in reactions catalyzed by enzymes obtained from microbial agents of specific species and strains. Products of dextran... (Review)
Review
Dextran is an exopolysaccharide synthesized in reactions catalyzed by enzymes obtained from microbial agents of specific species and strains. Products of dextran polysaccharides with different molecular weights are suitable for diverse pharmaceutical and clinical uses. Dextran solutions have multiple characteristics, including viscosity, solubility, rheological, and thermal properties; hence, dextran has been studied for its commercial applications in several sectors. Certain bacteria can produce extracellular polysaccharide dextran of different molecular weights and configurations. Dextran products of diverse molecular weights have been used in several industries, including medicine, cosmetics, and food. This article aims to provide an overview of the reports on dextran applications in blood transfusion and clinical studies and its biosynthesis. Information has been summarized on enzyme-catalyzed reactions for dextran biosynthesis from sucrose and on the bio-transformation process of high molecular weight dextran molecules to obtain preparations of diverse molecular weights and configurations.
Topics: Dextrans; Humans; Blood Transfusion; Molecular Weight
PubMed: 38939916
DOI: 10.31083/j.fbe1602017 -
Frontiers in Microbiology 2024Exploring the bacterial community in the rhizosphere was of great value for understanding how this species adapted to the saline-alkali environment and for the rational...
Exploring the bacterial community in the rhizosphere was of great value for understanding how this species adapted to the saline-alkali environment and for the rational development and use of saline-alkali soils. In this study, high-throughput sequencing technology was used to investigate the diversity characteristics and distribution patterns of soil bacterial communities in the rhizosphere of -dominated communities in the Hetao Irrigation Distract, Inner Mongolia, China. The relationships among bacterial characteristics, soil physicochemical properties and vegetation in four sampling sites were analyzed. The soil bacterial communities in the rhizosphere of -dominated communities were mainly composed of 16 phyla (i.e., and ), and these populations accounted for more than 99% of the total bacterial community. At the genus level, the main bacterial communities comprised and , which accounted for 15.70% of the total bacterial community. An alpha diversity analysis indicated that the richness and diversity of rhizosphere soil bacteria differed significantly among the sampling sites, and the bacterial richness and diversity indices of severe saline-alkali land were higher than those of light and moderate saline-alkali land. The principal component analysis (PCA) and linear discriminant analysis effect size (LEfSe) showed significant differences in the species composition of the rhizosphere soil bacterial community among different sampling sites. A correlation analysis showed that the number of bacterial species exhibited the highest correlation with the soil water content (SWC). The richness and evenness indices were significantly correlated with the SWC and SO , K and Mg concentrations. The electrical conductivity (EC), soluble ions (Na, CO + HCO , K, Ca, Mg, and SO ), SWC and vegetation coverage (VC) were the main drivers affecting the changes in its community structure. The bacterial community in the rhizosphere of enhanced the adaptability of to saline-alkali environment by participating in the cycling process of nutrient elements, the decomposition of organic matter and the production of plant growth regulating substances. These results provided a theoretical reference for further study on the relationship among rhizosphere soil microorganisms and salt tolerance in halophytes.
PubMed: 38939186
DOI: 10.3389/fmicb.2024.1358783 -
Journal of Extracellular Biology Jul 2023Interest in the use of extracellular vesicles (EVs) as biomarkers of disease is rapidly growing. However, one main unsolved issue in the EV field is finding a technique...
Interest in the use of extracellular vesicles (EVs) as biomarkers of disease is rapidly growing. However, one main unsolved issue in the EV field is finding a technique able to eliminate non-EV contaminants present in biofluid samples in a one-step isolation protocol. Due to the expansion and value of size exclusion chromatography (SEC) as one of the best EV isolation methods, we have tested several agarose resins with different agarose percentages, bead sizes and crosslinking features to optimize EV isolation. For this optimization of SEC, we first employed conditioned media from a melanoma cell culture, a simpler sample in comparison to biological fluids, but which also contains abundant contaminants such as soluble protein and lipoproteins (LPPs). The distinct agaroses and the combinations of resins with different agarose percentages in the same column were tested. Soluble protein, EVs and LPPs levels from the different eluted fractions were quantitated by immunodetection or absorbance measurements. Samples were also analysed by NTA and TEM to verify the yield and the LPP contamination. Different percentages of agarose resins (2%, 4% and 6%) yielded samples with increasing LPP contamination respectively, which was not improved in the columns that combined them. Crosslinking of the agarose did not affect EV isolation yield nor the LPP contamination. In contrast, reducing the bead size greatly improved EV purity. We thus selected 4% Rapid Run Fine agarose beads as the resin that more efficiently isolated EVs with almost no contamination of other particles. Using blood plasma samples, this resin also demonstrated an improved capacity in the isolation of EVs from LPPs in comparison to the agaroses most commonly used in the field and differential ultracentrifugation.
PubMed: 38939075
DOI: 10.1002/jex2.100