Ethyl Caffeate Can Inhibit Aryl Hydrocarbon Receptor (AhR) Signaling and AhR-Mediated Potentiation of Mast Cell Activation.

Ethyl caffeate (EC) is a natural phenolic compound that is present in several medicinal plants used to treat inflammatory disorders. However, its anti-inflammatory mechanisms are not fully understood. Here, we report that EC inhibits aryl hydrocarbon receptor (AhR) signaling and that this is associated with its anti-allergic activity. EC inhibited AhR activation, induced by the AhR ligands FICZ and DHNA in AhR signaling-reporter cells and mouse bone marrow-derived mast cells (BMMCs), as assessed by AhR target gene expressions such as CYP1A1. EC also inhibited the FICZ-induced downregulation of AhR expression and DHNA-induced IL-6 production in BMMCs. Furthermore, the pretreatment of mice with orally administered EC inhibited DHNA-induced CYP1A1 expression in the intestine. Notably, both EC and CH-223191, a well-established AhR antagonist, inhibited IgE-mediated degranulation in BMMCs grown in a cell culture medium containing significant amounts of AhR ligands. Furthermore, oral administration of EC or CH-223191 to mice inhibited the PCA reaction associated with the suppression of constitutive CYP1A1 expression within the skin. Collectively, EC inhibited AhR signaling and AhR-mediated potentiation of mast cell activation due to the intrinsic AhR activity in both the culture medium and normal mouse skin. Given the AhR control of inflammation, these findings suggest a novel mechanism for the anti-inflammatory activity of EC.

Comprehensive analysis of distinct circadian clock subtypes of adult diffuse glioma and their associations with clinicopathological, genetic, and epigenetic profiles.

The circadian clock (CC) has biological and clinical implications in gliomas. Most studies focused on CC effects on the tumor microenvironment and the application of chronotherapy. The present study focused on CC gene expression patterns and intracellular oncogenic activities. Glioma gene expression data were collected from The Human Cancer Genome Atlas (TCGA) project. After applying inclusion and exclusion criteria, we selected 666 patients from TCGA-GBM and TCGA-LGG projects and included important clinicopathological variables. The entire cohort was subjected to clustering analysis and divided into CC1 and CC2 subtypes based on statistical, biological, and clinical criteria. CC2 gliomas showed higher expression of BMAL1 and CRY1 and lower expression of CRY2 and PER2 (adjusted P < .001). CC2 gliomas had q higher activity of cell proliferation, metabolic reprogramming, angiogenesis, hypoxia, and many oncogenic signals (P < .001). The CC2 subtype contained a higher proportion of glioblastomas (P < .001) and had a worse prognosis (P < .001). Stratified Kaplan-Meier and multivariable Cox analyses illustrated that the CC subtype is an independent prognostic factor to clinicopathological characteristics (P < .001), genetic aberrations (P = .006), and biological processes (P < .001). Thus, this study shows statistical evidence of CC subtypes and their biological, and clinicopathological significance in adult gliomas.

SLC22A3 that encodes organic cation transporter-3 is associated with prognosis and immunogenicity of human lung squamous cell carcinoma.

Background: SLC22A3, the gene which encodes organic cation transporter (OCT)-3, has been linked to the prognosis of several types of cancer. However, its role in lung squamous cell carcinoma (LSCC) has not been addressed elsewhere. Methods: We analyzed gene expression, DNA methylation, and clinicopathological data from The Cancer Genome Atlas - Lung Squamous Cell Carcinoma (TCGA-LUSC) (n=501), a publicly available database exclusively consisting of LSCC patients. Using a 5 FPKM (fragments per kilobase of exon per million mapped fragments) cut-off, we divided LSCC patients into two groups: patients with tumors possessing high and low SLC22A3 expression (SLC22A3-high and SLC22A3-low, respectively). Prognostic significance was determined through Cox analyses and Kaplan-Meier curves for overall survival (OS) and disease-free survival (DFS). Differential methylation position (DMP), differentially gene expression, and pathway analyses were performed. Validation was carried out in GSE74777 (n=107), GSE37745 (n=66), GSE162520 (n=45) and GSE161537 (n=17). Results: SLC22A3-high LSCC patients had lower OS and DFS rates than SLC22A3-low LSCC patients. The different expression levels of SLC22A3 in LSCC were correlated with the methylation status of the SLC22A3 gene. Pathway analysis indicated that SLC22A3 expression levels were positively correlated with immune-related pathways such as inflammatory response and abundance of infiltrating immune cells in the tumor microenvironment (TME). Notably, in the SLC22A3-high group, many genes encoding immunological checkpoint inhibitory molecules were upregulated. In addition, SLC22A3 expression positively correlated with the Hot Oral Tumor (HOT) score, indicating high tumor immunogenicity. Conclusions: These findings suggest that high expression of SLC22A3 is associated with poor prognosis and high immunogenicity in LSCC tumors.