Tumor-repopulating cells evade ferroptosis via PCK2-dependent phospholipid remodeling.

Whether stem-cell-like cancer cells avert ferroptosis to mediate therapy resistance remains unclear. In this study, using a soft fibrin gel culture system, we found that tumor-repopulating cells (TRCs) with stem-cell-like cancer cell characteristics resist chemotherapy and radiotherapy by decreasing ferroptosis sensitivity. Mechanistically, through quantitative mass spectrometry and lipidomic analysis, we determined that mitochondria metabolic kinase PCK2 phosphorylates and activates ACSL4 to drive ferroptosis-associated phospholipid remodeling. TRCs downregulate the PCK2 expression to confer themselves on a structural ferroptosis-resistant state. Notably, in addition to confirming the role of PCK2-pACSL4(T679) in multiple preclinical models, we discovered that higher PCK2 and pACSL4(T679) levels are correlated with better response to chemotherapy and radiotherapy as well as lower distant metastasis in nasopharyngeal carcinoma cohorts.

SUMOylation of GMFB regulates its stability and function in retinal pigment epithelial cells under hyperglycemia.

BACKGROUND: Glia maturation factor beta (GMFB) is a growth and differentiation factor that acts as an intracellular regulator of signal transduction pathways. The small ubiquitin-related modifier (SUMO) modification, SUMOylation, is a posttranslational modification (PTM) that plays a key role in protein subcellular localization, stability, transcription, and enzymatic activity. Recent studies have highlighted the importance of SUMOylation in the inflammation and progression of numerous diseases. However, the relationship between GMFB and SUMOylation is unclear. RESULTS: Here, we report for the first time that GMFB and SUMO1 are markedly increased in retinal pigment epithelial (RPE) cells at the early stage of diabetes mellitus (DM) under hyperglycemia. The GMFΒ protein could be mono-SUMOylated by SUMO1 at the K20, K35, K58 or K97 sites. SUMOylation of GMFB led to its increased protein stability and subcellular translocation. Furthermore, deSUMOylation of GMFΒ downregulates multiple signaling pathways, including the Jak-STAT signaling pathway, p38 pathway and NF-kappa B signaling pathway. CONCLUSIONS: This work provides novel insight into the role of SUMOylated GMFB in RPE cells and provides a novel therapeutic target for diabetic retinopathy (DR).

Mitigating phospholipid peroxidation of macrophages in stress-induced tumor microenvironment by natural ALOX15/PEBP1 complex inhibitors.

BACKGROUND: The intricate interactions between chronic psychological stress and susceptibility to breast cancer have been recognized, yet the underlying mechanisms remain unexplored. Danzhi Xiaoyao Powder (DZXY), a traditional Chinese medicine (TCM) formula, has found clinical utility in the treatment of breast cancer. Macrophages, as the predominant immune cell population within the tumor microenvironment (TME), play a pivotal role in orchestrating tumor immunosurveillance. Emerging evidence suggests that lipid oxidation accumulation in TME macrophages, plays a critical role in breast cancer development and progression. However, a comprehensive understanding of the pharmacological mechanisms and active components of DZXY related to its clinical application in the treatment of stress-aggravated breast cancer remains elusive. PURPOSE: This study sought to explore the plausible regulatory mechanisms and identify the key active components of DZXY contributing to its therapeutic efficacy in the context of breast cancer. METHODS: Initially, we conducted an investigation into the relationship between the phagocytic capacity of macrophages damaged by psychological stress and phospholipid peroxidation using flow cytometry and LC-MS/MS-based phospholipomics. Subsequently, we evaluated the therapeutic efficacy of DZXY based on the results of the tumor size, tumor weight, the phospholipid peroxidation pathway and phagocytosis of macrophage. Additionally, the target-mediated characterization strategy based on binding of arachidonate 15-lipoxygenase (ALOX15) to phosphatidylethanolamine-binding protein-1 (PEBP1), including molecular docking analysis, microscale thermophoresis (MST) assay, co-immunoprecipitation analysis and activity verification, has been further implemented to reveal the key bio-active components in DZXY. Finally, we evaluated the therapeutic efficacy of isochlorogenic acid C (ICAC) based on the results of tumor size, tumor weight, the phospholipid peroxidation pathway, and macrophage phagocytosis in vivo. RESULTS: The present study demonstrated that phospholipid peroxides, as determined by LC-MS/MS-based phospholipidomics, triggered in macrophages, which in turn compromised their capacity to eliminate tumor cells through phagocytosis. Furthermore, we elucidate the mechanism behind stress-induced PEBP1 to form a complex with ALOX15, thereby mediating membrane phospholipid peroxidation in macrophages. DZXY, demonstrates potent anti-breast cancer therapeutic effects by disrupting the ALOX15/PEBP1 interaction and inhibiting phospholipid peroxidation, ultimately enhancing macrophages' phagocytic capability towards tumor cells. Notably, ICAC emerged as a promising active component in DZXY, which can inhibit the ALOX15/PEBP1 interaction, thereby mitigating phospholipid peroxidation in macrophages. CONCLUSION: Collectively, our findings elucidate stress increases the susceptibility of breast cancer by driving lipid peroxidation of macrophages and suggest the ALOX15/PEBP1 complex as a promising intervention target for DZXY.

Efficacy of bortezomib, cyclophosphamide, and dexamethasone for newly diagnosed POEMS syndrome patients.

Background: Due to the rarity of polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, the best first-line treatment has not been established, although there are several options in guidelines. The preferred treatments vary according to the preference of the physician and anecdote. Objectives: First, to analyze the efficacy of a new treatment mode in POEMS syndrome that uses the four-cycle treatment as the induction regimen, followed by sequential transplantation as the consolidation regimen for transplantation-eligible patients, or received another two-cycle treatment for transplantation-ineligible patients. Second, to compare the efficacy and safety of regimens with a proteasome inhibitor (bortezomib-cyclophosphamide-dexamethasone, BCD) or without a proteasome inhibitor (cyclophosphamide-dexamethasone ± thalidomide, CD ± T). Design: We conducted a retrospective study using real-world data from Capital Medical University, Xuanwu Hospital. Methods: A total of 34 newly diagnosed POEMS syndrome patients met Dispenzieri's diagnostic criteria, and those who completed at least four cycles of treatment from July 2013 to March 2021 were included. Results: The overall vascular endothelial growth factor (VEGF) response rate of this new treatment mode was 100%. The cumulative VEGF complete remission (CRV) rate was 67.9%, and the cumulative complete hematological response (CRH) rate was 55.6%. During the median 49-month follow-up, the 5-year-overall survival (OS) rate was 90.7%, the 3-year-progression-free survival (PFS) rate was 78.4%, and the 5-year-PFS rate was 73.8%. The BCD regimen achieved a 75% CRV rate (median time from diagnosis to CRV = 130 days) and 66.7% CRH rate (median time from diagnosis to CRH = 218 days). In addition, the VEGF response was less than the partial remission (PRV) after four-cycle induction treatment, which, together with a decrease on the Overall Neurological Limitation Scale of less than three points 1 year after consolidation treatment, was an independent poor prognostic factor. Conclusion: Bortezomib was well-tolerated by patients with POEMS syndrome. Compared with CD ± T regimen, BCD as the induction regimen achieved better VEGF response and earlier hematological remission. Autologous stem cell transplantation used as consolidation therapy further improved the neurological and hematological remission rates, resulting in better OS and PFS.

Mitochondria-targeting two-photon fluorescent probe for sequential recognition of Cu2+ and ATP in neurons and zebrafish.

Highly active mitochondria play a significant role in neuron function. Cu2+ and ATP levels in mitochondria regulate neuronal mitochondrial activity. However, mitochondrial activity was often evaluated by mitochondrial membrane potential. Less is known about the dynamics of Cu2+ and ATP in mitochondria. Herein, we developed a two-photon fluorescence probe (MP), which provided a determination of mitochondrial ATP and Cu2+. The fluorescence of MP showed remarkable quenching in the presence of Cu2+ and then gradually recovered in the presence of ATP, which can be used for sequential recognition. MP has high sensitivity to Cu2+ and ATP, with limits of detection (LOD) close to 0.31 nM and 13.6 nM, respectively. Using this useful probe, we monitor the fluctuation of concentrations of Cu2+ and ATP by fluorescence imaging at single neuron and zebrafish.

Reducing lipid peroxidation attenuates stress-induced susceptibility to herpes simplex virus type 1.

Psychological stress increases the susceptibility to herpes simplex virus type 1 (HSV-1) infection. There is no effective intervention due to the unknown pathogenesis mechanisms. In this study we explored the molecular mechanisms underlying stress-induced HSV-1 susceptibility and the antiviral effect of a natural compound rosmarinic acid (RA) in vivo and in vitro. Mice were administered RA (11.7, 23.4 mg·kg-1·d-1, i.g.) or acyclovir (ACV, 206 mg·kg-1·d-1, i.g.) for 23 days. The mice were subjected to restraint stress for 7 days followed by intranasal infection with HSV-1 on D7. At the end of RA or ACV treatment, mouse plasma samples and brain tissues were collected for analysis. We showed that both RA and ACV treatment significantly decreased stress-augmented mortality and alleviated eye swelling and neurological symptoms in HSV-1-infected mice. In SH-SY5Y cells and PC12 cells exposed to the stress hormone corticosterone (CORT) plus HSV-1, RA (100 µM) significantly increased the cell viability, and inhibited CORT-induced elevation in the expression of viral proteins and genes. We demonstrated that CORT (50 µM) triggered lipoxygenase 15 (ALOX15)-mediated redox imbalance in the neuronal cells, increasing the level of 4-HNE-conjugated STING, which impaired STING translocation from the endoplasmic reticulum to Golgi; the abnormality of STING-mediated innate immunity led to HSV-1 susceptibility. We revealed that RA was an inhibitor of lipid peroxidation by directly targeting ALOX15, thus RA could rescue stress-weakened neuronal innate immune response, thereby reducing HSV-1 susceptibility in vivo and in vitro. This study illustrates the critical role of lipid peroxidation in stress-induced HSV-1 susceptibility and reveals the potential for developing RA as an effective intervention in anti-HSV-1 therapy.

Short-term and long-term effect of nutrition intervention in the Linxian Dysplasia Nutrition Intervention Trial and the reason for disappearance of the intervention effect: A cohort study.

BACKGROUND: The objective of this study was to determine the short-term and long-term effects of a nutrition intervention in using 37 years of follow-up data. METHODS: The Linxian Dysplasia Population Nutrition Intervention Trial was a randomized, double-blind, placebo-controlled trial with 7 years of intervention and 30 years of follow-up. The Cox proportional hazard model was used for analyses. Subgroup analyses were conducted in age and sex subgroups, and the 30 years of follow-up were divided into two 15-year early and late periods. RESULTS: The results at 37 years did not indicate any effects on mortality from cancers or other diseases. In the first 15 years, the intervention decreased the overall risk of gastric cancer deaths in all participants (hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.58-1.00) and in the subgroup participants younger than 55 years (HR, 0.64; 95% CI, 0.43-0.96). In addition, in the group younger than 55 years (HR, 0.58; 95% CI, 0.35-0.96), the intervention decreased the risk of death from other diseases; and, in the group aged 55 years and older (HR, 0.75; 95% CI, 0.58-0.98), the intervention reduced the risk of death from heart disease. There were no significant results in the later 15 years, which indicated the disappearance of the intervention effect. Comparing demographic characteristics between those who died during the two periods, the participants who died later included more women, had a higher education level, had a lower smoking rate, were younger, and also more had a mild degree of esophageal dysplasia, representing a better lifestyle and health condition. CONCLUSIONS: Long-term follow-up indicated no effect of nutrition on deaths in a population with esophageal squamous dysplasia, further supporting the significance of continuous nutritional intervention for cancer protection. The pattern of protective effect of a nutrition intervention on gastric cancer in patients with esophageal squamous dysplasia was similar to that in the general population. Participants who died in the later period had more protective factors than those who died in the earlier period, contributing to the obvious effect of the intervention in early stage disease.

Glia maturation factor beta deficiency protects against diabetic osteoporosis by suppressing osteoclast hyperactivity.

Excessive osteoclast activation, which depends on dramatic changes in actin dynamics, causes osteoporosis (OP). The molecular mechanism of osteoclast activation in OP related to type 1 diabetes (T1D) remains unclear. Glia maturation factor beta (GMFB) is considered a growth and differentiation factor for both glia and neurons. Here, we demonstrated that Gmfb deficiency effectively ameliorated the phenotype of T1D-OP in rats by inhibiting osteoclast hyperactivity. In vitro assays showed that GMFB participated in osteoclast activation rather than proliferation. Gmfb deficiency did not affect osteoclast sealing zone (SZ) formation but effectively decreased the SZ area by decreasing actin depolymerization. When GMFB was overexpressed in Gmfb-deficient osteoclasts, the size of the SZ area was enlarged in a dose-dependent manner. Moreover, decreased actin depolymerization led to a decrease in nuclear G-actin, which activated MKL1/SRF-dependent gene transcription. We found that pro-osteoclastogenic factors (Mmp9 and Mmp14) were downregulated, while anti-osteoclastogenic factors (Cftr and Fhl2) were upregulated in Gmfb KO osteoclasts. A GMFB inhibitor, DS-30, targeting the binding site of GMFB and Arp2/3, was obtained. Biocore analysis revealed a high affinity between DS-30 and GMFB in a dose-dependent manner. As expected, DS-30 strongly suppressed osteoclast hyperactivity in vivo and in vitro. In conclusion, our work identified a new therapeutic strategy for T1D-OP treatment. The discovery of GMFB inhibitors will contribute to translational research on T1D-OP.

LincRNA ZNF529-AS1 inhibits hepatocellular carcinoma via FBXO31 and predicts the prognosis of hepatocellular carcinoma patients.

BACKGROUND: Invasion and metastasis of hepatocellular carcinoma (HCC) is still an important reason for poor prognosis. LincRNA ZNF529-AS1 is a recently identified tumour-associated molecule that is differentially expressed in a variety of tumours, but its role in HCC is still unclear. This study investigated the expression and function of ZNF529-AS1 in HCC and explored the prognostic significance of ZNF529-AS1 in HCC. METHODS: Based on HCC information in TCGA and other databases, the relationship between the expression of ZNF529-AS1 and clinicopathological characteristics of HCC was analysed by the Wilcoxon signed-rank test and logistic regression. The relationship between ZNF529-AS1 and HCC prognosis was evaluated by Kaplan‒Meier and Cox regression analyses. The cellular function and signalling pathways involved in ZNF529-AS1 were analysed by GO and KEGG enrichment analysis. The relationship between ZNF529-AS1 and immunological signatures in the HCC tumour microenvironment was analysed by the ssGSEA algorithm and CIBERSORT algorithm. HCC cell invasion and migration were investigated by the Transwell assay. Gene and protein expression were detected by PCR and western blot analysis, respectively. RESULTS: ZNF529-AS1 was differentially expressed in various types of tumours and was highly expressed in HCC. The expression of ZNF529-AS1 was closely correlated with the age, sex, T stage, M stage and pathological grade of HCC patients. Univariate and multivariate analyses showed that ZNF529-AS1 was significantly associated with poor prognosis of HCC patients and could be an independent prognostic indicator of HCC. Immunological analysis showed that the expression of ZNF529-AS1 was correlated with the abundance and immune function of various immune cells. Knockdown of ZNF529-AS1 in HCC cells inhibited cell invasion and migration and inhibited the expression of FBXO31. CONCLUSION: ZNF529-AS1 could be a new prognostic marker for HCC. FBXO31 may be the downstream target of ZNF529-AS1 in HCC.

Bioengineered Bacterial Membrane Vesicles with Multifunctional Nanoparticles as a Versatile Platform for Cancer Immunotherapy.

Inducing immunogenic cell death (ICD) is a critical strategy for enhancing cancer immunotherapy. However, inefficient and risky ICD inducers along with a tumor hypoxia microenvironment seriously limit the immunotherapy efficacy. Non-specific delivery is also responsible for this inefficiency. In this work, we report a drug-free bacteria-derived outer membrane vesicle (OMV)-functionalized Fe3O4-MnO2 (FMO) nanoplatform that realized neutrophil-mediated targeted delivery and photothermally enhanced cancer immunotherapy. In this system, modification of OMVs derived from Escherichia coli enhanced the accumulation of FMO NPs at the tumor tissue through neutrophil-mediated targeted delivery. The FMO NPs underwent reactive decomposition in the tumor site, generating manganese and iron ions that induced ICD and O2 that regulated the tumor hypoxia environment. Moreover, OMVs are rich in pathogen-associated pattern molecules that can overcome the tumor immunosuppressive microenvironment and effectively activate immune cells, thereby enhancing specific immune responses. Photothermal therapy (PTT) caused by MnO2 and Fe3O4 can not only indirectly stimulate systemic immunity by directly destroying tumor cells but also promote the enrichment of neutrophil-equipped nanoparticles by enhancing the inflammatory response at the tumor site. Finally, the proposed multi-modal treatment system with targeted delivery capability realized effective tumor immunotherapy to prevent tumor growth and recurrence.

A retrospective assessment of real-world experience with venetoclax and azacitidine therapy in elderly acute myeloid leukemia.

This study aimed to examine the effect of venetoclax coupled with azacytidine in treating older adults with relapsed and refractory (R/R) acute myeloid leukemia (AML). The clinical data of 10 senior patients with AML over 65 years old who were treated with venetoclax and azacytidine, including six patients with R/R AML, were retrospectively evaluated. This study comprised seven males and three females with a median age of 71 years. Five patients had at least one relapse, and one patient did not achieve remission after four cycles of azacytidine monotherapy, considering it resistant. AML with myelodysplasia-related changes was found in four cases. One of the 10 patients died early after 1-13 cycles of venetoclax plus azacytidine treatment due to a protracted period of neutropenia and severe lung infection induced by medications. Six of the remaining nine patients, including six R/R patients, achieved a complete remission (CR) or a CR with incomplete hematologic recovery (CRi). After two cycles of therapy, one patient did not react. Neutropenia lasted an average of 10.5 (6-15) days in all patients, with the most severe cases occurring in the second and third weeks of therapy. Three patients who tested positive for the TP53 gene mutation had the following outcomes: One relapsed patient has been in progression-free remission (PFS) for the past 24 months, whereas another has been in full remission but relapsed 2 months later. Another patient experienced complete remission in myelology for 4 months, but the variable allele fraction (VAF) value steadily rose, suggesting that the illness was on the verge of progressing. IDH2 gene alterations were found in three of four patients who obtained maintained CR for more than 18 months following recurrence. Venetoclax in combination with azacytidine is a successful and well-tolerated therapy for R/R AML in the elderly. Venetoclax and azacytidine may help patients with TP53 mutations and reduce VAF. The IDH2 mutation might be a good predictor of veneclax sensitivity. A notable adverse response in the treatment phase of the regimen is severe infection induced by neutropenia.

Phototheranostics for NIR fluorescence image guided PDT/PTT with extended conjugation and enhanced TICT.

Introducing donor and acceptor into conjugated system can facilitate the intersystem crossing (ISC) rate to increase the generation of ROS. Twisted intramolecular charge transfer (TICT) state could favor enhance the nonradiative transition and photothermal conversion efficiency (PCE). Herein, diketopyrrolopyrrole (DPP) core functionalized benzene (PDDP), thiophene (TDPP), triphenylamine-conjugated benzene (TPA-PDDP) and thiophene (TPA-TDPP) derivatives were designed and synthesized. Electrochemistry experiments revealed the heavy atom effect and the introduction of triphenylamine reduced the energy level of TPA-TDPP and improved the ability to generate 1O2 (1O2 QY = 50%). In addition, in the aggregated state, introduction of thiophene, triphenylamine, and long alkyl chains promoted the twisting effect, preventing the intermolecular π-π interaction and enhancing the PCE of TPA-TDPP (38.7%). In vivo fluorescence imaging showed that TPA-TDPP NPs can target the tumor site with the enhanced permeability and retention (EPR) effect and presented excellent synergistic photodynamic/photothermal therapy.

GPX4 deficiency-dependent phospholipid peroxidation drives motor deficits of ALS.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by oxidative stress that triggers motor neurons loss in the brain and spinal cord. However, the mechanisms underlying the exact role of oxidative stress in ALS-associated neural degeneration are not definitively established. Oxidative stress-generated phospholipid peroxides are known to have extensive physiological and pathological consequences to tissues. Here, we discovered that the deficiency of glutathione peroxidase 4 (GPX4), an essential antioxidant peroxidase, led to the accumulation of phospholipid peroxides and resulted in a loss of motor neurons in spinal cords of ALS mice. Mutant human SOD1G93A transgenic mice were intrathecally injected with neuron-targeted adeno-associated virus (AAV) expressing GPX4 (GPX4-AAV) or phospholipid peroxidation inhibitor, ferrostatin-1. The results showed that impaired motor performance and neural loss induced by SOD1G93A toxicity in the lumbar spine were substantially alleviated by ferrostatin-1 treatment and AAV-mediated GPX4 delivery. In addition, the denervation of neuron-muscle junction and spinal atrophy in ALS mice were rescued by neural GPX4 overexpression, suggesting that GPX4 is essential for the motor neural maintenance and function. In comparison, conditional knockdown of Gpx4 in the spinal cords of Gpx4fl/fl mice triggered an obvious increase of phospholipid peroxides and the occurrence of ALS-like motor phenotype. Altogether, our findings underscore the importance of GPX4 in maintaining phospholipid redox homeostasis in the spinal cord and presents GPX4 as an attractive therapeutic target for ALS treatment.

PDK1- and PDK2-mediated metabolic reprogramming contributes to the TGFß1-promoted stem-like properties in head and neck cancer.

BACKGROUND: Resistance to chemotherapeutic drugs is a key factor for cancer recurrence and metastases in head and neck cancer (HNC). Cancer stem cells (CSCs) in tumors have self-renewal, differentiation, and higher drug resistance capabilities, resulting in a poor prognosis for patients. In glucose metabolism, pyruvate dehydrogenase kinase (PDK) inhibits pyruvate dehydrogenase and impedes pyruvate from being metabolized into acetyl-CoA and entering the tricarboxylic acid cycle to generate energy. Studies have reported that PDK1 and PDK2 inhibition suppresses the growth, motility, and drug resistance of cancer cells. Furthermore, while TGFß1 levels are persistently elevated in HNC patients with poor prognosis, the role of PDK isoforms in the TGFß1-promoted progression and stem-like properties of HNC is unclear. METHODS: Levels of PDK1 and PDK2 were evaluated in HNC tissue microarrays by immunohistochemistry to explore potential clinical relevance. PDK1 and PDK2 were knocked down by the lentivirus shRNA system to investigate their role in TGFß1-promoted tumor progression in vitro. RESULTS: We found that PDK2 levels were increased in the later stage of HNC tissues compared to constant PDK1 expression. After PDK1 and PDK2 knockdown, we discovered increased ATP production and decreased lactate production in TGFß1-treated and untreated HNC cells. However, only PDK2 silencing significantly inhibited the clonogenic ability of HNC cells. We subsequently found that TGFß1-promoted migration and invasion capabilities were decreased in PDK1 and PDK2 knockdown cells. The tumor spheroid-forming capability, motility, CSC genes, and multidrug-resistant genes were downregulated in PDK1 and PDK2 silencing CSCs. PDK1 and PDK2 inhibition reversed cisplatin and gemcitabine resistance of CSCs, but not paclitaxel resistance. CONCLUSION: The results demonstrated that the PDK1- and PDK2-mediated Warburg effect contributes to the TGFß1-enhanced stemness properties of HNC. Therefore, PDK1 and PDK2 may serve as molecular targets for the combination therapy of HNC.

Customized optimization of lignocellulolytic enzyme cocktails for efficient conversion of pectin-rich biomass residues.

Pectin is a major component in many agricultural feedstocks. Despite the wide use in industrial production of cellulases and hemicellulases, the fungus Trichoderma reesei lacks a complete enzyme set for pectin degradation. In this study, three representative pectinolytic enzymes were expressed and screened for their abilities to improve the efficiency of T. reesei enzymes on the conversion of different agricultural residues. By replacing 5 % of the T. reesei proteins, endopolygalacturonase and pectin lyase remarkably increased the release of sugars from inferior tobacco leaves. In contrast, pectin methylesterase showed the strongest improving effect (by 31.1 %) on the hydrolysis of beetroot residue. The pectin in beetroot residue was only mildly degraded with the supplementation of pectin methylesterase, which allowed the extraction of pectin keeping the original emulsifying activity with a 51.1 % higher yield. The results provide a basis for precise optimization of lignocellulolytic enzyme systems for targeted valorization of pectin-rich agricultural residues.

Cell-membrane-targeted near-infrared fluorescent probe for detecting extracellular ATP.

Extracellular adenosine triphosphate (ATP) as a signal molecule plays a key role in tumor progression and metastasis. Therefore, the development of a fluorescent probe to detect extracellular ATP is crucial for tumor treatment. However, small-molecule fluorescent probes have better advantages than biological probes, such as low price, easy modification, and optical tunability, but still remain highly challenging and rarely explored in extracellular ATP detection. Here, a near-infrared small molecule fluorescent probe (NIR-P) with hydrophobic alkyl chains and hydrophilic macrocyclic polyamines was prepared for the detection of extracellular ATP. The NIR-P exhibited enhanced fluorescence upon binding to ATP by electrostatic interaction and π-π interaction between phosphates and macrocyclic polyamines, adenines and benzene rings with a limit of detection (LOD) of 21 nM. In addition, with similarity and intermiscibility to the cell membrane, the NIR-P can specifically target cell membranes and image extracellular ATP. This work provides a cell-membrane-targeted fluorescent probe used for extracellular ATP detection.

The Efficacy of DW and T1-W MRI Combined with CT in the Preoperative Evaluation of Cholesteatoma.

OBJECTIVE: This study aims to assess the efficacy of diffusion-weighted (DW) and T1-weighted (T1W) magnetic resonance imaging (MRI) combined with high-resolution computed tomography (HRCT) (together as DW-T1W-CT) in the preoperative evaluation of the presence and extent of cholesteatoma, which helps determine whether a patient is suitable for transcanal endoscopic ear surgery (TEES). METHODS: This retrospective study included 35 patients (18 male and 17 female) aged from 2 to 81 years diagnosed with chronic otitis media with or without cholesteatoma, who had received surgical treatment and a preoperative MRI and HRCT during the period of December 2015 to December 2020 at Cathay General Hospital. We compared the preoperative DW-T1W-CT findings with the intraoperative findings and final pathologic diagnosis. The accurate predictive value was evaluated using the presence of cholesteatoma and its extent. RESULTS: Regarding the efficacy of detecting cholesteatoma, we found a sensitivity of 92% (23/25 cases with cholesteatoma), a specificity of 90% (9/10 cases without cholesteatoma), and an overall accurate predictive value of 91.4% (32/35) by using combined DW-T1W-CT imaging. With regard to evaluating the extent of cholesteatoma, the combined DW-T1W-CT images obtained an accurate predictive value of 84% (21/25 cases of cholesteatoma). CONCLUSION: Combined DW-T1W-CT has been proven to be a reliable tool in detecting the presence of cholesteatoma. It is also useful in preoperatively depicting the extent of cholesteatoma, which is crucial for determining whether a patient is suitable for TEES, aiding in surgical planning and patient consultation.

CXCR3 isoform A promotes head and neck cancer progression by enhancing stem-like property and chemoresistance.

BACKGROUND: The chemokine network orchestrates the cancer stem-like property and consequently participates in cancer progression. CXCR3 contributes cancer progressive property and immunomodulation in the tumor microenvironment. The two major isoforms of CXCR3 are scrutinized and the divergence is showed that CXCR3A promotes cancer cell growth and motility while CXCR3B functions contrarily in many studies. However, rare studies illustrate the role of CXCR3 isoforms in cancer stem-like property and chemoresistance, especially in head and neck cancer (HNC). METHODS: Levels of CXCR3, CXCR3B, and Sox2 were determined in HNC tissue microarray by immunohistochemistry staining to explore potential clinical relevance. Lentivirus-mediated CXCR3-isoform overexpression with MTS assay, clonogenic assay, transwell migration, sphere formation, and chemo-drug susceptibility were implemented to investigate the role of CXCR3-isofoms in HNC. RESULTS: High levels of CXCR3 were significantly associated with advanced stage (p < 0.01), regional lymph node metastasis (p < 0.05), and poor differentiation (p < 0.005) and further correlated with worse survival rate in oral cancer patients (p = 0.036). Higher levels of CXCR3B were found in regional lymphatic invasion of HNC and progressive stage of squamous cell carcinoma. Elevated Sox2 expression was significantly associated with the advanced stage of HNC in the oral cavity, and demonstrated a co-expression pattern with CXCR3B. Furthermore, lentivirus-mediated overexpression of CXCR3A and CXCR3B in SAS human oral cancer cells promoted cell mobility. CXCR3A overexpression enhanced sphere-forming ability and chemoresistance of CSCs by upregulating stemness-related genes. CONCLUSION: This study first provides a novel insight of CXCR3 isoform A in HNC cancer progression via regulating cancer stem-like properties and chemoresistance, suggesting that CXCR3A may be a prognostic marker and novel target for HNC therapy.

Phospholipid peroxidation inhibits autophagy via stimulating the delipidation of oxidized LC3-PE.

Phospholipid peroxidation of polyunsaturated fatty acids at the bis-allylic position drives ferroptosis. Here we identify a novel role for phospholipid peroxidation in the inhibition of autophagy. Using in vitro and in vivo models, we report that phospholipid peroxidation induced by glutathione peroxidase-4 inhibition and arachidonate 15-lipoxygenase overexpression leads to overload of peroxidized phospholipids and culminate in inhibition of autophagy. Functional and lipidomics analysis further demonstrated that inhibition of autophagy was associated with an increase of peroxidized phosphatidylethanolamine (PE) conjugated LC3. We further demonstrate that autophagy inhibition occurred due to preferential cleavage of peroxidized LC3-PE by ATG4B to yield delipidated LC3. Mouse models of phospholipid peroxidation and autophagy additionally supported a role for peroxidized PE in autophagy inhibition. Our results agree with the recognized role of endoplasmic reticulum as the primary source for autophagosomal membranes. In summary, our studies demonstrated that phospholipid peroxidation inhibited autophagy via stimulating the ATG4B-mediated delipidation of peroxidized LC3-PE.

Purple tea water extract blocks RANKL-induced osteoclastogenesis through modulation of Akt/GSK3ß and Blimp1-Irf8 pathways.

A number of studies demonstrated that some tea extracts exert inhibitory effects on osteoclastogenesis induced by receptor activator of nuclear factor κB ligand (RANKL). However, the effect of purple tea, a famous tea in China, on osteoclastogenesis remains unclear. In this study, a water-based purple tea extract (PTE) was found to suppress osteoclast formation, osteoclastic resorption pit area formation, and F-actin ring formation within RANKL-stimulated bone marrow macrophages (BMMs). Furthermore, our results demonstrated that PTE could inhibit expression of master transcription factors NFATc1 and c-Fos and their target genes DC-STAMP, Ctsk, and Atp6v0d2. Western blot analysis revealed that PTE treatment led to reduced RANKL-induced phosphorylation of Akt and GSK3ß without altering transient activation of NF-κB and MAPKs (p38, JNK, ERK1/2) signaling. In addition, the results demonstrated that PTE treatment of RANKL-stimulated BMMs could down-regulate Blimp1 expression and up-regulate Irf8 expression. In summary, these results suggest that PTE treatment of RANKL-stimulated BMMs inhibited osteoclast differentiation via modulation of Blimp1-Irf8 and Akt/GSK3ß signaling pathways. Aligning with our in vitro results, in vivo PTE administration ameliorated bone loss in LPS-treated mice. Taken together, the results presented in this work suggest that PTE treatment possesses anti-osteolytic activity.