Knowledge, attitude, and practice of e-cigarette use among undergraduate students: A comparative study between China and Indonesia.

INTRODUCTION: The health risks associated with e-cigarettes are currently the focus of tobacco control efforts and public health initiatives. Given that China and Indonesia have the highest rates of adult smoking worldwide, it is imperative to gain a comprehensive understanding of e-cigarette prevalence among college students in these two nations. METHODS: From May to June 2023, a cross-sectional study was employed to conduct an online questionnaire survey among college students in three universities located in Kunming (China) and Jakarta (Indonesia), respectively. The chi-squared test was utilized to compare the rates/ratios, while binary logistic regression analysis was applied to examine the factors influencing e-cigarette knowledge, attitude, and practice. RESULTS: A total of 1327 individuals were included in the investigation. The proportion of Indonesian students (75.6%) with a high level of e-cigarette knowledge was lower than that observed among Chinese students (87.4%) (χ2=29.7, p<0.001). Additionally, the prevalence of e-cigarette use among Indonesian students (9.4%) was higher compared to their Chinese counterparts (3.0%) (χ2=22.32, p<0.001). Binary logistic regression analysis revealed that age, place of residence, studies, gender, and e-cigarette use by friends and family, significantly influenced knowledge levels and attitudes toward e-cigarettes in both countries (p<0.05). CONCLUSIONS: Despite the positive knowledge, attitudes, and practices towards e-cigarettes among undergraduate students in both countries, a notable knowledge gap exists concerning the harmful effects of e-cigarettes. Chinese students had better e-cigarette knowledge and demonstrated lower usage rates, suggesting that heightened awareness plays a favorable role in preventing e-cigarette use. Furthermore, it becomes imperative for policymakers and health educators to focus on specific factors, such as the influence of close friends and family members, as well as the area of residence.

Visible-Light-Promoted α-C(sp3)-H Amination of Ethers with Azoles and Amides.

A visible-light-induced highly efficient C(sp3)-H amination of ethers with amides and azoles has been presented under mild conditions via a nitrogen- and carbon-centered radical coupling process. This protocol successfully utilizes 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and tert-butyl nitrite (TBN) as cocatalysts to deliver the aminated products of ethers under aerobic conditions. Notably, the developed reaction features the corresponding products in good yields (up to 93%) with a wide substrate scope. The mechanistic study indicates that C-N bond formation proceeds via a direct radical cross-coupling process. Preliminary biological activity analysis indicates that the resulting products have good and selective inhibitory activity on osteosarcoma (OS) cell lines and are promising for use as hits for drug discovery.

LIN28B inhibition sensitizes cells to p53-restoring PPI therapy through unleashed translational suppression.

p53 is the most highly mutated tumor suppressor across multiple types of human cancers. The level and function of p53 are fine-tuned through multifaced mechanisms in which the protein-protein interaction between p53 and MDM2 is considered as a major circuit. Recent studies suggest therapeutic strategy attempts to restore p53 function by small molecule inhibitors targeting p53-MDM2 interaction can be a promising direction in treating cancers with wild-type or functional p53. Currently, clinical tests of the p53-MDM2 protein-protein interaction inhibitors (PPIs) are underway. However, it remains elusive about the biomarkers that may predict the therapeutic responses to those inhibitors. Here we report that RNA-binding protein LIN28B directly regulates p53 through binding to the 5'΄ untranslated region of p53 mRNA and blocks its translation by competing with a translation enhancer protein, ribosomal protein L26 (RPL26). This regulatory mechanism of LIN28B does not involve let-7 maturation or the canonical protein turnover pathway of p53. Furthermore, we show that inhibition of LIN28B unleashes the translational suppression of p53 through RPL26, and leads to enhanced sensitivities of cancer cells to inhibitors of p53-MDM2 interaction. Together, we demonstrate a competitive regulatory mechanism of p53 by LIN28B, which has important implications in developing biomarkers to the therapies aiming to reinstate p53 function.

Integrated Chemoenzymatic Approach to Streamline the Assembly of Complex Glycopeptides in the Liquid Phase.

Glycosylation of proteins is a complicated post-translational modification. Despite the significant progress in glycoproteomics, accurate functions of glycoproteins are still ambiguous owing to the difficulty in obtaining homogeneous glycopeptides or glycoproteins. Here, we describe a streamlined chemoenzymatic method to prepare complex glycopeptides by integrating hydrophobic tag-supported chemical synthesis and enzymatic glycosylations. The hydrophobic tag is utilized to facilitate peptide chain elongation in the liquid phase and expeditious product separation. After removal of the tag, a series of glycans are installed on the peptides via efficient glycosyltransferase-catalyzed reactions. The general applicability and robustness of this approach are exemplified by efficient preparation of 16 well-defined SARS-CoV-2 O-glycopeptides, 4 complex MUC1 glycopeptides, and a 31-mer glycosylated glucagon-like peptide-1. Our developed approach will open up a new range of easy access to various complex glycopeptides of biological importance.

Novel 2-phenyl-3-(Pyridin-2-yl) thiazolidin-4-one derivatives as potent inhibitors for proliferation of osteosarcoma cells in vitro and in vivo.

Due to unknown pathogenesis and unidentified drug target, no drug for the treatment of osteosarcoma (OS) has been launched to the market. Herein, thiazolidinone 1a was discovered as a hit compound by phenotypic screening with an in-house patrimonial collection of structural diversity. The following SAR (Structure-Activity Relationship) study affords the final water-soluble lead compound (R)-8i as a potential inhibitor for the proliferation of OS cells by the modulation of solubility of the compounds with remarkable cellular potency (IC50 = 21.9 nM for MNNG/HOS cells) and in vivo efficacy (52.9% inhibition OS growth in mice), as well as pharmacokinetic properties. (R)-8i also significantly suppresses OS cell migration in vitro and showed to be well-tolerated. Our preliminary investigation shows that the effects of (R)-8i are not dependent on p53 and myoferlin (MYOF). These results suggest that (R)-8i might be a potential drug candidate for OS treatment.

OLIG2 maintenance is not essential for diffuse intrinsic pontine glioma cell line growth but regulates tumor phenotypes.

BACKGROUND: Diffuse intrinsic pontine glioma (DIPG) is a pediatric lethal high-grade brainstem glioma with no effective therapies. OLIG2 (oligodendrocyte transcription factor 2) was reported to be critical for the growth of a DIPG cell line CCHMC-DIPG-1. Surprisingly, we found that the CCHMC-DIPG-1 cells express little OLIG2 and exhibit a mesenchymal phenotype, which raised a question regarding the role of OLIG2 in the growth of DIPG cells. METHODS: We evaluated the function of OLIG2 in different DIPG cell lines through molecular and genetic approaches and performed transcriptomic and genomic landscape profiling including whole-genome bisulfite sequencing, RNA-seq, ATAC-seq, and ChIP-seq. shRNA-mediated knockdown and CRISPR-Cas9-mediated knockout approaches were utilized to assess OLIG2 functions in DIPG cell growth. RESULTS: We found that DIPG cells are phenotypically heterogeneous and exhibit the characteristics of distinct malignant gliomas including proneural, classical, and mesenchymal subtypes. OLIG2 knockdown did not impact the growth of CCHMC-DIPG-1 cells, wherein OLIG2 is epigenetically silenced. Moreover, OLIG2 deletion did not substantially impair OLIG2-expressing proneural-like DIPG growth but led to an upregulation of HIPPO-YAP1 and epidermal growth factor receptor (EGFR) signaling and a tumor phenotype shift. Targeting HIPPO-YAP1 and EGFR signaling in OLIG2-deficient DIPG cells inhibited tumor cell growth. CONCLUSIONS: Our data indicate that OLIG2 is dispensable for DIPG growth but regulates the phenotypic switch of DIPG tumor cells. OLIG2 downregulation leads to deregulation of adaptive YAP1 and EGFR signaling. Targeting YAP1 and EGFR pathways inhibits the growth of OLIG2-deficient DIPG cells, pointing to a therapeutic potential by targeting adaptive signaling to treat DIPG tumors with nominal OLIG2 expression.

Emerging role of SWI/SNF complex deficiency as a target of immune checkpoint blockade in human cancers.

Mammalian SWI/SNF complex is a key chromatin remodeler that reshapes nucleosomes and regulates DNA accessibility. Mutations in SWI/SNF subunits are found in a broad spectrum of human cancers; however, the mechanisms of how these aberrations of SWI/SNF complex would impact tumorigenesis and cancer therapeutics remain to be elucidated. Studies have demonstrated that immune checkpoint blockade (ICB) therapy is promising in cancer treatment. Nevertheless, suitable biomarkers that reliably predict the clinical response to ICB are still lacking. Emerging evidence has suggested that SWI/SNF components play novel roles in the regulation of anti-tumor immunity, and SWI/SNF deficiency can be therapeutically targeted by ICB. These findings manifest the prominence of the SWI/SNF complex as a stratification biomarker that predicts treatment (therapeutic) response to ICB. In this review, we summarize the recent advances in ICB therapy by harnessing the cancer-specific vulnerability elicited by SWI/SNF deficiency. We provide novel insights into a comprehensive understanding of the underlying mechanisms by which SWI/SNF functions as a modulator of anti-tumor immunity.

Microstructure and Mechanical Properties of AlSi7Mg0.6 Aluminum Alloy Fabricated by Wire and Arc Additive Manufacturing Based on Cold Metal Transfer (WAAM-CMT).

Wire and arc additive manufacturing based on cold metal transfer (WAAM-CMT) has aroused wide public concern in recent years as one of the most advanced technologies for manufacturing components with complex geometries. However, the microstructure and mechanical properties of the parts fabricated by WAAM-CMT technology mostly are intolerable for engineering application and should be improved necessarily. In this study, heat treatment was proposed to optimize the microstructure and enhance mechanical properties in the case of AlSi7Mg0.6 alloy. After heat treatment, the division between coarse grain zone and fine grain zone of as-deposited samples seemed to disappear and the distribution of Si and Mg elements was more uniform. What is more, the yield strength and ultimate tensile strength were improved significantly, while the ductility could be sustained after heat treatment. The improvement of strength is attributed to precipitation strengthening, and the shape change of Si phase. No reduction in ductility is due to the higher work hardening rate caused by nanostructured precipitate. It is proved that heat treatment as an effective method can control the microstructure and enhance comprehensive mechanical properties, which will boost rapid development of WAAM industrial technology.

Programming of Schwann Cells by Lats1/2-TAZ/YAP Signaling Drives Malignant Peripheral Nerve Sheath Tumorigenesis.

Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive Schwann cell (SC)-lineage-derived sarcomas. Molecular events driving SC-to-MPNST transformation are incompletely understood. Here, we show that human MPNSTs exhibit elevated HIPPO-TAZ/YAP expression, and that TAZ/YAP hyperactivity in SCs caused by Lats1/2 loss potently induces high-grade nerve-associated tumors with full penetrance. Lats1/2 deficiency reprograms SCs to a cancerous, progenitor-like phenotype and promotes hyperproliferation. Conversely, disruption of TAZ/YAP activity alleviates tumor burden in Lats1/2-deficient mice and inhibits human MPNST cell proliferation. Moreover, genome-wide profiling reveals that TAZ/YAP-TEAD1 directly activates oncogenic programs, including platelet-derived growth factor receptor (PDGFR) signaling. Co-targeting TAZ/YAP and PDGFR pathways inhibits tumor growth. Thus, our findings establish a previously unrecognized convergence between Lats1/2-TAZ/YAP signaling and MPNST pathogenesis, revealing potential therapeutic targets in these untreatable tumors.

A reciprocal regulatory loop between TAZ/YAP and G-protein Gαs regulates Schwann cell proliferation and myelination.

Schwann cell (SC) myelination in the peripheral nervous system is essential for motor function, and uncontrolled SC proliferation occurs in cancer. Here, we show that a dual role for Hippo effectors TAZ and YAP in SC proliferation and myelination through modulating G-protein expression and interacting with SOX10, respectively. Developmentally regulated mutagenesis indicates that TAZ/YAP are critical for SC proliferation and differentiation in a stage-dependent manner. Genome-wide occupancy mapping and transcriptome profiling reveal that nuclear TAZ/YAP promote SC proliferation by activating cell cycle regulators, while targeting critical differentiation regulators in cooperation with SOX10 for myelination. We further identify that TAZ targets and represses Gnas, encoding Gαs-protein, which opposes TAZ/YAP activities to decelerate proliferation. Gnas deletion expands SC precursor pools and blocks peripheral myelination. Thus, the Hippo/TAZ/YAP and Gαs-protein feedback circuit functions as a fulcrum balancing SC proliferation and differentiation, providing insights into molecular programming of SC lineage progression and homeostasis.

Olig2-Targeted G-Protein-Coupled Receptor Gpr17 Regulates Oligodendrocyte Survival in Response to Lysolecithin-Induced Demyelination.

Demyelinating diseases, such as multiple sclerosis, are known to result from acute or chronic injury to the myelin sheath and inadequate remyelination; however, the underlying molecular mechanisms remain unclear. Here, we performed genome occupancy analysis by chromatin immunoprecipitation sequencing in oligodendrocytes in response to lysolecithin-induced injury and found that Olig2 and its downstream target Gpr17 are critical factors in regulating oligodendrocyte survival. After injury to oligodendrocytes, Olig2 was significantly upregulated and transcriptionally targeted the Gpr17 locus. Gpr17 activation inhibited oligodendrocyte survival by reducing the intracellular cAMP level and inducing expression of the pro-apoptotic gene Xaf1 The protein kinase A signaling pathway and the transcription factor c-Fos mediated the regulatory effects of Gpr17 in oligodendrocytes. We showed that Gpr17 inhibition elevated Epac1 expression and promoted oligodendrocyte differentiation. The loss of Gpr17, either globally or specifically in oligodendrocytes, led to an earlier onset of remyelination after myelin injury in mice. Similarly, pharmacological inhibition of Gpr17 with pranlukast promoted remyelination. Our findings indicate that Gpr17, an Olig2 transcriptional target, is activated after injury to oligodendrocytes and that targeted inhibition of Gpr17 promotes oligodendrocyte remyelination. SIGNIFICANCE STATEMENT: Genome occupancy analysis of oligodendrocytes in response to lysolecithin-mediated demyelination injury revealed that Olig2 and its downstream target Gpr17 are part of regulatory circuitry critical for oligodendrocyte survival. Gpr17 inhibits oligodendrocyte survival through activation of Xaf1 and cell differentiation by reducing Epac1 expression. The loss of Gpr17 in mice led to precocious myelination and an earlier onset of remyelination after demyelination. Pharmacological inhibition of Gpr17 promoted remyelination, highlighting the potential for Gpr17-targeted therapeutic approaches in demyelination diseases.

Olig2-Dependent Reciprocal Shift in PDGF and EGF Receptor Signaling Regulates Tumor Phenotype and Mitotic Growth in Malignant Glioma.

Malignant gliomas exhibit extensive heterogeneity and poor prognosis. Here we identify mitotic Olig2-expressing cells as tumor-propagating cells in proneural gliomas, elimination of which blocks tumor initiation and progression. Intriguingly, deletion of Olig2 resulted in tumors that grow, albeit at a decelerated rate. Genome occupancy and expression profiling analyses reveal that Olig2 directly activates cell-proliferation machinery to promote tumorigenesis. Olig2 deletion causes a tumor phenotypic shift from an oligodendrocyte precursor-correlated proneural toward an astroglia-associated gene expression pattern, manifest in downregulation of platelet-derived growth factor receptor-α and reciprocal upregulation of epidermal growth factor receptor (EGFR). Olig2 deletion further sensitizes glioma cells to EGFR inhibitors and extends the lifespan of animals. Thus, Olig2-orchestrated receptor signaling drives mitotic growth and regulates glioma phenotypic plasticity. Targeting Olig2 may circumvent resistance to EGFR-targeted drugs.

The G protein α subunit Gαs is a tumor suppressor in Sonic hedgehog-driven medulloblastoma.

Medulloblastoma, the most common malignant childhood brain tumor, exhibits distinct molecular subtypes and cellular origins. Genetic alterations driving medulloblastoma initiation and progression remain poorly understood. Herein, we identify GNAS, encoding the G protein Gαs, as a potent tumor suppressor gene that, when expressed at low levels, defines a subset of aggressive Sonic hedgehog (SHH)-driven human medulloblastomas. Ablation of the single Gnas gene in anatomically distinct progenitors in mice is sufficient to induce Shh-associated medulloblastomas, which recapitulate their human counterparts. Gαs is highly enriched at the primary cilium of granule neuron precursors and suppresses Shh signaling by regulating both the cAMP-dependent pathway and ciliary trafficking of Hedgehog pathway components. Elevation in levels of a Gαs effector, cAMP, effectively inhibits tumor cell proliferation and progression in Gnas-ablated mice. Thus, our gain- and loss-of-function studies identify a previously unrecognized tumor suppressor function for Gαs that can be found consistently across Shh-group medulloblastomas of disparate cellular and anatomical origins, highlighting G protein modulation as a potential therapeutic avenue.

Molecular mechanism of hepatocellular carcinoma-specific antitumor activity of the novel thienopyridine derivative TP58.

Despite progress made in the treatment of hepatocellular carcinoma (HCC), there is no curable treatment. Novel therapies are therefore needed. In our previous study on the design and synthesis of a small molecular inhibitor targeting Aurora kinase, we discovered a novel thienopyridine derivative compound (1g, TP58) which displayed the most potent and relatively specific inhibition of the proliferation of HepG2 human hepatoma cells in vitro. However, the molecular mechanism remains to be elucidated. Herein, in vitro and in vivo studies were conducted to further verify its antitumor activity against HCC. cDNA microarray and two-dimensional protein gel electrophoresis technology were utilized to elucidate the mechanism of HCC-specific inhibition of TP58. Flow cytometry analysis displayed that TP58 can significantly induce G0/G1 arrest in HepG2 cells. Sixteen genes involved in cell cycle regulation were found to be dysregulated following TP58 treatment using microarray technology. Nine proteins whose expression was altered (corresponding to 10 spots identified as differentially expressed) were identified by proteomic analysis. Further study showed that TP58 can modulate the expression of some liver-enriched transcription factors (LETFs) and liver-specific marker genes, such as hepatic nuclear factor (HNF-4) and α-fetoprotein (AFP). These findings may help explain the mechanism of HCC-specific antitumor activity of TP58 and provide some useful insight for anti-HCC drug design and future use of thienopyridine derivatives in HCC therapy.

Proteomics analysis of human umbilical vein endothelial cells treated with resveratrol.

In the past decade, the small polyphenol resveratrol has received widespread attention as either a potential therapy or as a preventive agent for numerous age-related chronic diseases, including cardiovascular atherosclerosis, cancer, hypertension, and diabetes, but the biological processes and molecular pathways by which resveratrol induces these beneficial effects, as well as its safety and toxicology remain largely undefined. To explore the molecular mechanisms of resveratrol involved in the amelioration of endothelial dysfunction and vascular disease, in the present study the protein profile changes of human umbilical vein endothelial cells in response to resveratrol treatment were investigated using proteomics approaches (2-DE combined with MS/MS). As a result, four down-regulated protein species named elongation factor 2 (EEF2), carboxymethyl-cofilin-1 (cofilin-1), acetyl-eukaryotic translation initiation factor 5A-1 (acetyl-EIF5A) and barrier-to-autointegration factor, and five up-regulated protein species named heat shock protein beta-1 (HSP27), phospho-HSP27, phospho-stathmin, Nicotinate-nucleotide pyrophosphorylase and 1,2-dihydroxy-3-keto-5-methylthiopentene dioxygenase were identified. Among them, two translation-related protein species (EEF2 and acetyl-EIF5A) were the most significantly changed (over tenfold). Phospho-EEF2 was further verified to be dramatically up-regulated by immunoblot assays. It is notable that in the present study several protein species with post-transcriptional modification (carboxymethyl-, acetyl-, and phospho-) were found to be altered following exposure to resveratrol. These findings may improve our understanding of the molecular mechanisms underlying the pleiotropic effects of resveratrol on endothelial cells.

A critical role of vascular endothelial growth factor D in zebrafish embryonic vasculogenesis and angiogenesis.

The VEGF family comprises seven members that are designated VEGF-A, VEGF-B, VEGF-C, VEGF-D, VEGF-E, placental growth factor (PlGF), and VEGF-F. Of these factors, VEGF-D plays important roles for angiogenesis and lymphangiogenesis, and could promote tumor growth and lymphatic metastasis. In this study, we identified a zebrafish VEGF-D homolog that encodes a 272 amino acid protein including a PDGF (platelet-derived growth factor) domain characteristic to VEGF family. Expression profile demonstrated that the VEGF-D began expressed from 13 somite stage. Microinjecting zVEGF-D mRNA into zebrafish 1-cell stage embryos resulted in severe misguidance of intersegmental vessels (ISV) and abnormal connection between dorsal aorta and caudal vein. Microangiography indicated that these abnormal ISVs were not functional. Our studies therefore identified the first non-mammalian VEGF-D and established its in vivo role for vascular system development during vertebrate embryogenesis and provided an alternative animal model to further reveal functions of VEGF-D.