Capsaicin reverses cisplatin resistance in tongue squamous cell carcinoma by inhibiting the Warburg effect and facilitating mitochondrial-dependent apoptosis via the AMPK/AKT/mTOR axis.

Cisplatin is commonly used for the chemotherapy of tongue squamous cell carcinoma (TSCC); however, adverse side effects and drug resistance impact its therapeutic efficacy. Capsaicin is an active ingredient in chili peppers that exerts antitumor effects, whether it exerts antitumor effects on cisplatin-resistant cells remains unknown. Therefore, in this study, we investigated the effect of capsaicin on cisplatin resistance in TSCC cells and explored the underlying mechanisms. A cisplatin-resistant TSCC cell line was established by treated with increasing cisplatin concentrations. Combined treatment with cisplatin and capsaicin decreased the glucose consumption and lactate dehydrogenase activity and increased the adenosine triphosphate production both in vitro and in vivo, suggesting the inhibition of the Warburg effect. Moreover, this combined treatment induced cell apoptosis and significantly upregulated the levels of proapoptotic proteins, such as Bax, cleaved caspase-3, -7, and -9, and apoptosis-inducing factor. In contrast, levels of the antiapoptotic protein, Bcl-2, were downregulated. Additionally, LKB1 and AMPK activities were stimulated, whereas those of AKT and mTOR were suppressed. Notably, AMPK knockdown abolished the inhibitory effects of capsaicin and cisplatin on the AKT/mTOR signaling pathway and Warburg effect. Overall, combined treatment with capsaicin and cisplatin reversed cisplatin resistance by inhibiting the Warburg effect and facilitating mitochondrial-dependent apoptosis via the AMPK/AKT/mTOR axis. Our findings suggest combination therapy with capsaicin and cisplatin as a potentially novel strategy and highlight capsaicin as a promising adjuvant drug for TSCC treatment.

Rocaglamide regulates iron homeostasis by suppressing hepcidin expression.

The anemia of inflammation (AI) is characterized by the presence of inflammation and abnormal elevation of hepcidin. Accumulating evidence has proved that Rocaglamide (RocA) was involved in inflammation regulation. Nevertheless, the role of RocA in AI, especially in iron metabolism, has not been investigated, and its underlying mechanism remains elusive. Here, we demonstrated that RocA dramatically suppressed the elevation of hepcidin and ferritin in LPS-treated mice cell line RAW264.7 and peritoneal macrophages. In vivo study showed that RocA can restrain the depletion of serum iron (SI) and transferrin (Tf) saturation caused by LPS. Further investigation showed that RocA suppressed the upregulation of hepcidin mRNA and downregulation of Fpn1 protein expression in the spleen and liver of LPS-treated mice. Mechanistically, this effect was attributed to RocA's ability to inhibit the IL-6/STAT3 pathway, resulting in the suppression of hepcidin mRNA and subsequent increase in Fpn1 and TfR1 expression in LPS-treated macrophages. Moreover, RocA inhibited the elevation of the cellular labile iron pool (LIP) and reactive oxygen species (ROS) induced by LPS in RAW264.7 cells. These findings reveal a pivotal mechanism underlying the roles of RocA in modulating iron homeostasis and also provide a candidate natural product on alleviating AI.

Tra2ß exerts tumor-promoting effects via GSK3/ß-catenin signaling in oral squamous cell carcinoma.

OBJECTIVES: The splicing factor transformer-2 homolog beta (Tra2ß) plays a pivotal role in various cancers. Nonetheless, its role in oral squamous cell carcinoma (OSCC) has not been comprehensively explored. This study sought to discern the influence of Tra2ß on OSCC and its underlying mechanisms. MATERIALS AND METHODS: We assessed Tra2ß expression in OSCC utilizing immunohistochemistry, qRT-PCR, and western blotting techniques. siRNA transfection was used to silence Tra2ß. Whole transcriptome RNA sequencing (RNA-seq) analysis was carried out to reveal the alternative splicing (AS) events. KEGG pathway analysis enriched the related pathways. Colony formation, transwell, wound healing, and Annexin V-FITC/PI were employed to appraise the consequences of Tra2ß silencing on OSCC. RESULTS: Tra2ß was highly expressed in both OSCC tissues and cell lines. Knockdown of Tra2ß-regulated AS events with skipped exon (SE) accounts for the highest proportion. Meanwhile, downregulation of Tra2ß reduced cell proliferation, migration, and invasion, however increasing cell apoptosis. Moreover, Wnt signaling pathway involved in the function of Tra2ß knockdown which was demonstrated directly by a discernible reduction in the expression of GSK3/ß-catenin signaling axis. CONCLUSIONS: These findings suggest that knockdown of Tra2ß may exert anti-tumor effects through the GSK3/ß-catenin signaling pathway in OSCC.

Real time imaging of cell-permeable nanoreactor with SERS for insight into cellular processes.

Intracellular glucose detection is crucial due to its pivotal role in metabolism and various physiological processes. Precise glucose monitoring holds significance in diabetes management, metabolic studies, and biotechnological applications. In this study, we developed an innovative and expedient cell-permeable nanoreactor for intracellular glucose based on surface-enhanced Raman scattering (SERS). The nanoreactor was designed with gold nanoparticles (AuNPs), which were engineered with glucose oxide (GOx) and a H2O2-responsive Raman reporter 2-mercaptohydroquinone (2-MHQ). The interaction between 2-MHQ and H2O2 generated by glucose and GOx could simultaneously induce the appearance in the peak at 985 cm-1. Our results showed excellent performance in detecting glucose within the concentration range from 0.1 µM to 10 mM, with a low detection limitation of 14.72 nM. In addition, the glucose distribution in single HeLa cells was evaluated by real time SERS mapping. By combining noble metal particles and natural oxidases, the nanoreactor possesses both Raman activity and enzymatic functionality, thus enables sensitive glucose detection and facilitates imaging at a single cell level, which offers an insightful monitoring of cellular processes.

Portable Hydrogel Kits Made with Bimetallic Nanozymes for Point-of-Care Testing of Perfluorooctanesulfonate.

Perfluorooctanesulfonate (PFOS), an emerging organic contaminant, necessitates robust on-site detection strategies to safeguard human health and ecological balance. This study introduces a novel point-of-care testing (POCT) platform, combining a hydrogel kit with nanozymes and smartphone technology, for the highly sensitive detection of PFOS. The strategy utilizes copper-substituted cobalt-based Prussian blue analogue nanoboxes (CuCo-PBA NBs), which exhibit intricate hollow structures and remarkable peroxidase-like catalytic activity, efficiently catalyzing the oxidation of chromogenic substrates with hydrogen peroxide (H2O2). Density functional theory calculations elucidate the adsorption dynamics of H2O2 on CuCo-PBA NBs, identifying the factors that improve the catalytic efficiency. The colorimetric POCT platform, integrating the hydrogel kit with a smartphone interface, demonstrates practical utility and achieves a detection limit of 1.43 × 10-8 mol L-1 for PFOS. This research not only presents a new nanozyme design for PFOS detection in diverse matrices, such as lake water, whole blood, urine, and milk, but also paves the way for developing a portable and efficient POCT platform for a variety of emerging contaminants.

MITF regulates the subcellular location of HIF1α through SUMOylation to promote the invasion and metastasis of daughter cells derived from polyploid giant cancer cells.

High concentrations of cobalt chloride (CoCl2) can induce the formation of polyploid giant cancer cells (PGCCs) in various tumors, which can produce daughter cells with strong proliferative, migratory and invasive abilities via asymmetric division. To study the role of hypoxia­inducible factor (HIF) 1α in the formation of PGCCs, colon cancer cell lines Hct116 and LoVo were used as experimental subjects. Western blotting, nuclear and cytoplasmic protein extraction and immunocytochemical experiments were used to compare the changes in the expression and subcellular localization of HIF1α, microphthalmia­associated transcription factor (MITF), protein inhibitor of activated STAT protein 4 (PIAS4) and von Hippel­Lindau disease tumor suppressor (VHL) after treatment with CoCl2. The SUMOylation of HIFα was verified by co­immunoprecipitation assay. After inhibiting HIF1α SUMOylation, the changes in proliferation, migration and invasion abilities of Hct116 and LoVo were compared by plate colony formation, wound healing and Transwell migration and invasion. In addition, lysine sites that led to SUMOylation of HIF1α were identified through site mutation experiments. The results showed that CoCl2 can induce the formation of PGCCs with the expression level of HIF1α higher in treated cells than in control cells. HIF1α was primarily located in the cytoplasm of control cell. Following CoCl2 treatment, the subcellular localization of HIF1α was primarily in the nuclei of PGCCs with daughter cells (PDCs). After treatment with SUMOylation inhibitors, the nuclear HIF1α expression in PDCs decreased. Furthermore, their proliferation, migration and invasion abilities also decreased. After inhibiting the expression of MITF, the expression of HIF1α decreased. MITF can regulate HIF1α SUMOylation. Expression and subcellular localization of VHL and HIF1α did not change following PIAS4 knockdown. SUMOylation of HIF1α occurs at the amino acid sites K391 and K477 in PDCs. After mutation of the two sites, nuclear expression of HIF1α in PDCs was reduced, along with a significant reduction in the proliferation, migration and invasion abilities. In conclusion, the post­translation modification regulated the subcellular location of HIF1α and the nuclear expression of HIF1α promoted the proliferation, migration and invasion abilities of PDCs. MITF could regulate the transcription and protein levels of HIF1α and participate in the regulation of HIF1α SUMOylation.

ACSL4-mediated membrane phospholipid remodeling induces integrin ß1 activation to facilitate triple-negative breast cancer metastasis.

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and has a poor prognosis and a high propensity to metastasize. Lipid metabolism has emerged as a critical regulator of tumor progression and metastasis in other cancer types. Characterization of the lipid metabolic features of TNBC could provide important insights into the drivers of TNBC metastasis. Here, we showed that metastatic TNBC tumors harbor more unsaturated phospholipids, especially long-chain polyunsaturated fatty acids, at the sn-2 position of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) compared to primary tumors. Metastatic TNBC tumors upregulated ACSL4, a long-chain polyunsaturated acyl-CoA synthetase that drives the preferential incorporation of polyunsaturated fatty acids into phospholipids, resulting in the alteration of membrane phospholipid composition and properties. Moreover, ACSL4-mediated phospholipid remodeling of the cell membrane induced lipid-raft localization and activation of integrin ß1 in a CD47-dependent manner, which led to downstream focal adhesion kinase (FAK) phosphorylation that promoted metastasis. Importantly, pharmacological inhibition of ACSL4 suppressed tumor growth and metastasis and increased chemosensitivity in TNBC models in vivo. These findings indicate that ACSL4-mediated phospholipid remodeling enables TNBC metastasis and can be inhibited as a potential strategy to improve the efficacy of chemotherapy in TNBC.

Research advances in microfluidic collection and detection of virus, bacterial, and fungal bioaerosols.

Bioaerosols are airborne suspensions of fine solid or liquid particles containing biological substances such as viruses, bacteria, cellular debris, fungal spores, mycelium, and byproducts of microbial metabolism. The global Coronavirus disease 2019 (COVID-19) pandemic and the previous emergence of severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and influenza have increased the need for reliable and effective monitoring tools for bioaerosols. Bioaerosol collection and detection have aroused considerable attention. Current bioaerosol sampling and detection techniques suffer from long response time, low sensitivity, and high costs, and these drawbacks have forced the development of novel monitoring strategies. Microfluidic technique is considered a breakthrough for high performance analysis of bioaerosols. In recent years, several emerging methods based on microfluidics have been developed and reported for collection and detection of bioaerosols. The unique advantages of microfluidic technique have enabled the integration of bioaerosol collection and detection, which has a higher efficiency over conventional methods. This review focused on the research progress of bioaerosol collection and detection methods based on microfluidic techniques, with special attention on virus aerosols and bacterial aerosols. Different from the existing reviews, this work took a unique perspective of the targets to be collected and detected in bioaerosols, which would provide a direct index of bioaerosol categories readers may be interested in. We also discussed integrated microfluidic monitoring system for bioaerosols. Additionally, the application of bioaerosol detection in biomedicine was presented. Finally, the current challenges in the field of bioaerosol monitoring are presented and an outlook given of future developments.

Invasive mucinous adenocarcinoma of the lung with bronchorrhea - A marked reduction volume of sputum after SARS-CoV-2 infection.

Bronchorrhea is a watery sputum volume of at least 100 mL/day, which is commonly associated with lung malignancies. We report a 57-year-old woman was admitted to the hospital with a cough, profuse sputum. Chest CTs showed crazy paving pattern and lung nodules. Cell nests were visible on the Thinprep Cytologic Test. The case was considered an invasive mucinous adenocarcinoma of the lung combined with bronchorrhea. Significantly, the sputum volume declined rapidly and did not rise again when the patient was diagnosed with COVID-19 and treated with nirmatrelvir/ritonavir. This case is suggestive of studies related to regulatory mediators associated with bronchorrhea.

Clinical features, disease progression, and nuclear imaging in ATXN2-related parkinsonism in a longitudinal cohort.

BACKGROUND: Spinocerebellar ataxia 2 (SCA2) with a low range of CAG repeat expansion of ATXN2 gene can present with predominant or isolated parkinsonism that closely resembles Parkinson's disease (PD). This study is aimed at comparing clinical features, disease progression, and nuclear imaging between ATXN2-related parkinsonism (ATXN2-P) and PD. METHODS: Three hundred and seventy-seven clinically diagnosed PD with family history were screened by multiplex ligation-dependent probe amplification, whole-exome sequencing or target sequencing, and dynamic mutation testing of 10 SCA subtypes. The baseline and longitudinal clinical features as well as the dual-tracer positron emission tomography (PET) imaging were compared between ATXN2-P and genetically undefined familial PD (GU-fPD). RESULTS: Fifteen ATXN2-P patients from 7 families and 50 randomly selected GU-fPD patients were evaluated. Significantly less resting tremor and more symmetric signs were observed in ATXN2-P than GU-fPD. No significant difference was found in motor progression and duration from onset to occurrence of fluctuation, dyskinesia, and recurrent falls between the two groups. Cognitive impairment and rapid-eye-movement sleep behavior disorder were more common in ATXN2-P. During follow-up, olfaction was relatively spared, and no obvious progression of cognition dysfunction evaluated by Mini-Mental State Examination scores was found in ATXN2-P. PET results of ATXN2-P demonstrated a symmetric, diffuse, and homogenous dopamine transporter loss of bilateral striatum and a glucose metabolism pattern inconsistent with that in PD. CONCLUSIONS: Symmetric motor signs and unique nuclear imaging might be the clues to distinguish ATXN2-P from GU-fPD.

High Serum Albumin Levels were Associated with Acute Kidney Injury in Pediatric Surgical Intensive Care Units.

INTRODUCTION: There are limited studies revealing the association between serum albumin concentrations and acute kidney injury (AKI) in critically ill children. METHODS: This was a multicenter retrospective study. Children consecutively admitted to four pediatric surgical intensive care units (PSICUs) between January 2016 and December 2020 were screened for analysis. Patients without recorded albumin values during the PSICU stay were excluded. Data were extracted from the electronic medical records systems of the hospitals. AKI was defined according to the Kidney Disease Improving Global Outcome (KDIGO) guidelines. The associations between serum albumin levels and AKI were assessed by using logistic regression models. RESULTS: A total of 7802 children were included in the analysis. The median age of the children was 1.0 (interquartile range (IQR), 0.0-4.0) years. There were 3214 (41.2 %) children who developed AKI. In the univariate logistic regression model, serum albumin levels were associated with AKI (odds ratio (OR) = 1.04, 95 % confidence interval (CI) 1.04-1.05). After adjusting for covariates, serum albumin showed an independent association with AKI (OR = 1.04, 95 % CI 1.03-1.05). Albumin levels above 39.43 g/L (OR = 1.036, 95 % CI 1.002-1.070) were associated with AKI in the unadjusted cubic spline. In the adjusted cubic spline, albumin levels above 40.41 g/L (OR = 1.061, 95 % CI 1.003-1.122) were associated with AKI. CONCLUSION: High serum albumin was associated with AKI in critically ill children in the PSICU. Further studies are needed to validate our findings. TYPE OF STUDY: Prognostic Study. LEVEL OF EVIDENCE: LEVEL II.

Transcription factor PbMYB80 regulates lignification of stone cells and undergoes RING finger protein PbRHY1-mediated degradation in pear fruit.

The Chinese white pear (Pyrus bretschneideri) fruit carries a high proportion of stone cells, adversely affecting fruit quality. Lignin is a main component of stone cells in pear fruit. In this study, we discovered that a pear MYB transcription factor, PbMYB80, binds to the promoters of key lignin biosynthesis genes and inhibits their expression. Stable overexpression of PbMYB80 in Arabidopsis showed that lignin deposition and secondary wall thickening were inhibited, and the expression of the lignin biosynthesis genes in transgenic Arabidopsis was decreased. Transient overexpression of PbMYB80 in pear fruit inhibited lignin metabolism and stone cell development, and the expression of some genes in the lignin metabolism pathway was reduced. In contrast, silencing PbMYB80 with VIGS increased the lignin and stone cell content in pear fruit, and increased expression of genes in the lignin metabolism pathway. By screening a pear fruit cDNA library in yeast, we found that PbMYB80 binds to a RING finger (PbRHY1) protein. We also showed that PbRHY1 exhibits E3 ubiquitin ligase activity and degrades ubiquitinated PbMYB80 in vivo and in vitro. This investigation contributes to a better understanding of the regulation of lignin biosynthesis in pear fruit, and provides a theoretical foundation for increasing pear fruit quality at the molecular level.

Oxidized ATM governs stemness of breast cancer stem cell through regulating ubiquitylation and acetylation switch.

Cancer stem cells (CSCs), as parts of tumor initiation cells, play a crucial role to tumorigenesis, development and recurrence. However, the complicated mechanisms of CSCs to adapt to tumor microenvironment and its stemness maintenance remains unclear. Here, we show that oxidized ATM, a hypoxia-activated cytoplasm ATM, acts a novel function to maintain CSC stemness in triple-negative breast cancer cells (BCSCs) via regulating histone H4 acetylation. Mechanistically, oxidized ATM phosphorylates TRIM21 (a E3 ubiquitin ligase) serine 80 and serine 469. Serine 80 phosphorylation of TRIM21 is essential for the ubiquitination activity of TRIM21. TRIM21 binds with SIRT1 (one of deacetylase), resulting in ubiquitylation-mediated degradation of SIRT1. The reduced SIRT1 leads to increase of histone H4 acetylation, thus facilitating CSC-related gene expression. Clinical data verify that high level of ATM in breast tumors is positively correlated with malignant grade, and is closely related with low SIRT1, high p-TRIM21, and high CD44 expression. In conclusion, our study provides a novel mechanism by which oxidized ATM governing BCSCs stemness and reveals an important link among oxidized ATM, histone acetylation, and BCSCs maintenance.

Generation and Characterization of Monoclonal Antibodies against Swine Acute Diarrhea Syndrome Coronavirus Spike Protein.

Swine acute diarrhea syndrome coronavirus (SADS-CoV), a member of the family Coronaviridae and the genus Alphacoronavirus, primarily affects piglets under 7 days old, causing symptoms such as diarrhea, vomiting, and dehydration. It has the potential to infect human primary and passaged cells in vitro, indicating a potential risk of zoonotic transmission. In this study, we successfully generated and purified six monoclonal antibodies (mAbs) specifically targeting the spike protein of SADS-CoV, whose epitope were demonstrated specificity to the S1A or S1B region by immunofluorescence assay and enzyme-linked immunosorbent assay. Three of these mAbs were capable of neutralizing SADS-CoV infection on HeLa-R19 and A549. Furthermore, we observed that SADS-CoV induced the agglutination of erythrocytes from both humans and rats, and the hemagglutination inhibition capacity and antigen-antibody binding capacity of the antibodies were assessed. Our study reveals that mAbs specifically targeting the S1A domain demonstrated notable efficacy in suppressing the hemagglutination phenomenon induced by SADS-CoV. This finding represents the first instance of narrowing down the protein region responsible for SADS-CoV-mediated hemagglutination to the S1A domain, and reveals that the cell attachment domains S1A and S1B are the main targets of neutralizing antibodies.

Immunoproximity biotinylation reveals the axon initial segment proteome.

The axon initial segment (AIS) is a specialized neuronal compartment required for action potential generation and neuronal polarity. However, understanding the mechanisms regulating AIS structure and function has been hindered by an incomplete knowledge of its molecular composition. Here, using immuno-proximity biotinylation we further define the AIS proteome and its dynamic changes during neuronal maturation. Among the many AIS proteins identified, we show that SCRIB is highly enriched in the AIS both in vitro and in vivo, and exhibits a periodic architecture like the axonal spectrin-based cytoskeleton. We find that ankyrinG interacts with and recruits SCRIB to the AIS. However, loss of SCRIB has no effect on ankyrinG. This powerful and flexible approach further defines the AIS proteome and provides a rich resource to elucidate the mechanisms regulating AIS structure and function.

Saliva Analysis Based on Microfluidics: Focusing the Wide Spectrum of Target Analyte.

Saliva is one of the most critical human body fluids that can reflect the state of the human body. The detection of saliva is of great significance for disease diagnosis and health monitoring. Microfluidics, characterized by microscale size and high integration, is an ideal platform for the development of rapid and low-cost disease diagnostic techniques and devices. Microfluidic-based saliva testing methods have aroused considerable interest due to the increasing need for noninvasive testing and frequent or long-term testing. This review briefly described the significance of saliva analysis and generally classified the targets in saliva detection into pathogenic microorganisms, inorganic substances, and organic substances. By using this classification as a benchmark, the state-of-the-art research results on microfluidic detection of various substances in saliva were summarized. This work also put forward the challenges and future development directions of microfluidic detection methods for saliva.

Spatially resolved mapping of proteome turnover dynamics with subcellular precision.

Cellular activities are commonly associated with dynamic proteomic changes at the subcellular level. Although several techniques are available to quantify whole-cell protein turnover dynamics, such measurements often lack sufficient spatial resolution at the subcellular level. Herein, we report the development of prox-SILAC method that combines proximity-dependent protein labeling (APEX2/HRP) with metabolic incorporation of stable isotopes (pulse-SILAC) to map newly synthesized proteins with subcellular spatial resolution. We apply prox-SILAC to investigate proteome dynamics in the mitochondrial matrix and the endoplasmic reticulum (ER) lumen. Our analysis reveals a highly heterogeneous distribution in protein turnover dynamics within macromolecular machineries such as the mitochondrial ribosome and respiratory complexes I-V, thus shedding light on their mechanism of hierarchical assembly. Furthermore, we investigate the dynamic changes of ER proteome when cells are challenged with stress or undergoing stimulated differentiation, identifying subsets of proteins with unique patterns of turnover dynamics, which may play key regulatory roles in alleviating stress or promoting differentiation. We envision that prox-SILAC could be broadly applied to profile protein turnover at various subcellular compartments, under both physiological and pathological conditions.