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The major challenge in COVID‐19 vaccine effectiveness is immune escape by SARS‐CoV‐2 variants. To overcome this, an Omicron‐specific messenger RNA (mRNA) vaccine was designed. The extracellular domain of the spike of the Omicron variant was fused with a modified GCN4 trimerization domain with low immunogenicity (TSomi). After immunization with TSomi mRNA in hamsters, animals were challenged with SARS‐CoV‐2 virus. The raised nonneutralizing antibodies or cytokine secretion responses can recognize both Wuhan S and Omicron S. However, the raised antibodies neutralized SARS‐CoV‐2 Omicron virus infection but failed to generate Wuhan virus neutralizing antibodies. Surprisingly, TSomi mRNA immunization protected animals from Wuhan virus challenge. These data indicated that non‐neutralizing antibodies or cellular immunity may play a more important role in vaccine‐induced protection than previously believed. Next‐generation COVID‐19 vaccines using the Omicron S antigen may provide sufficient protection against ancestral or current SARS‐CoV‐2 variants. [ABSTRACT FROM AUTHOR]

Head and neck squamous cell carcinoma (HNSCC) is one of the leading causes of cancer deaths worldwide, especially in male. With poor prognosis, significant portions of patients with HNSCC die due to cancer recurrence and tumor metastasis after chemotherapy and targeted therapies. The HNSCC FaDu cell ectopic expression of Twist, a key transcriptional factor of epithelial–mesenchymal transition (EMT), which triggers EMT and results in the acquisition of a mesenchymal phenotype, was used as the cell model. Our results demonstrated that treatment with newly synthesized 2‐(3‐hydroxyphenyl)‐5‐methylnaphthyridin‐4‐one (CSC‐3436), a flavonoid derivative, elicited changes in its cell morphology, upregulated E‐cadherin messenger RNA and protein expression, downregulated N‐cadherin, vimentin, and CD133 (a marker associated with tumor‐initiating cells) in FaDu‐pCDH‐Twist cells. Moreover, CSC‐3436 exposure reduced B cell‐specific Moloney murine leukemia virus integration site 1 (Bmi1) expression regulated by Twist and further suppressed the direct co‐regulation of E‐cadherin by Twist and Bmi1. Interestingly, CSC‐3436 reduced EMT, cancer stemness, and migration/invasion abilities through the inhibition of the Twist/Bmi1‐Akt/β‐catenin pathway. Most importantly, our findings provided new evidence that CSC‐3436 played a crucial role in therapeutic targeting to Bmi1 and its molecular pathway in HNSCC, and it will be valuable in prognostic prediction and treatment. 2‐(3‐Hydroxyphenyl)‐5‐methylnaphthyridin‐4‐one (CSC‐3436) reduced Twist‐induced epithelial–mesenchymal transition, tumor‐initiating abilities and migration/invasion through the inhibition of the Twist/Bmi1‐Akt/β‐catenin pathway. Simultaneously, CSC‐3436 exposure reduced B cell‐specific Moloney murine leukemia virus integration site 1 (Bmi1) regulated by Twist and in further suppressed the direct co‐regulation of E‐cadherin by Twist and Bmi1. [ABSTRACT FROM AUTHOR]

Gastrointestinal stromal tumor (GIST) is a type of KIT‐driven cancer. KIT gene mutations are found in approximately 80% of GISTs, and most of these mutations occur in exon 9 and exon 11. Imatinib has been successfully used as a first‐line treatment for advanced GIST, with a significant improvement in progression‐free survival (PFS) and overall survival. However, disease progression might develop due to primary or secondary resistance to imatinib. Sunitinib and regorafenib have been approved as second‐ and third‐line treatments for advanced GIST patients, with median PFS values of 6.8 and 4.8 months, respectively. However, these relatively modest improvements in PFS underscore the need for more effective KIT inhibitors. BPR1J373 is a multitargeted kinase inhibitor that has been shown to inhibit the proliferation of KIT‐driven acute myeloid leukemia cells in vitro and in vivo. In this study, we found that BPR1J373 inhibited proliferation and induced apoptosis by targeting KIT in GIST cells with KIT gene mutations. BPR1J373 also induced cell cycle arrest and senescent change in KIT‐mutant GIST48 cells, probably by targeting aurora kinase A. In the KIT‐null COS‐1 cell‐based system, BPR1J373 effectively inhibited KIT with single or double mutations of KIT developed in GIST. The antiproliferative effect was also consistently evident in GIST430 tumor‐grafted mice. The results suggest that BPR1J373 could be a potential anticancer drug for GIST and deserves further investigation for clinical applications. Our study shows that BPR1J373 effectively inhibits the proliferation of KIT‐mutated gastrointestinal stromal tumor in vitro and in vivo. It is a potential anticancer drug and deserves further investigation for its applications in clinical use. [ABSTRACT FROM AUTHOR]

Chronic inflammation, coupled with alcohol, betel quid, and cigarette consumption, is associated with oral squamous cell carcinoma (OSCC). Interleukin-1 beta (IL-1β) is a critical mediator of chronic inflammation and implicated in many cancers. In this study, we showed that increased pro-IL-1β expression was associated with the severity of oral malignant transformation in a mouse OSCC model induced by 4-Nitroquinolin-1-oxide (4-NQO) and arecoline, two carcinogens related to tobacco and betel quid, respectively. Using microarray and quantitative PCR assay, we showed that pro-IL-1β was upregulated in human OSCC tumors associated with tobacco and betel quid consumption. In a human OSCC cell line TW2.6, we demonstrated nicotine-derived nitrosamine ketone (NNK) and arecoline stimulated IL-1β secretion in an inflammasome-dependent manner. IL-1β treatment significantly increased the proliferation and dysregulated the Akt signaling pathways of dysplastic oral keratinocytes (DOKs). Using cytokine antibodies and inflammation cytometric bead arrays, we found that DOK and OSCC cells secreted high levels of IL-6, IL-8, and growth-regulated oncogene-α following IL-1β stimulation. The conditioned medium of IL-1β-treated OSCC cells exerted significant proangiogenic effects. Crucially, IL-1β increased the invasiveness of OSCC cells through the epithelial-mesenchymal transition (EMT), characterized by downregulation of E-cadherin, upregulation of Snail, Slug, and Vimentin, and alterations in morphology. These findings provide novel insights into the mechanism underlying OSCC tumorigenesis. Our study suggested that IL-1β can be induced by tobacco and betel quid-related carcinogens, and participates in the early and late stages of oral carcinogenesis by increasing the proliferation of dysplasia oral cells, stimulating oncogenic cytokines, and promoting aggressiveness of OSCC. J. Cell. Physiol. 230: 875-884, 2015. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

We have demonstrated previously that terbinafine (TB), an oral antifungal agent used in the treatment of superficial mycosis, suppresses proliferation of various cultured human cancer cells in vitro and in vivo by inhibiting DNA synthesis and activating apoptosis. In our study, we further demonstrated that TB at a range of concentrations (0-120 μM) dose-dependently decreased cell number in cultured human umbilical vascular endothelial cells (HUVEC). Terbinafine was not cytotoxic at a concentration of 120 μM, indicating that it may have an inhibitory effect on the cell proliferation in HUVEC. The TB-induced inhibition of cell growth rate is reversible. [ [ABSTRACT FROM AUTHOR]

The oral absorption of a therapeutic peptide (such as exenatide; EXT) that can improve glycemic control in the treatment of type 2 diabetes is limited by multiple barriers of the intestinal epithelium. This work presents an oil‐structured nanoemulsion system that consists of a phase‐changeable fatty acid that allows EXT (EXT@PC/NEMs) to be delivered orally and absorbed efficiently in the small intestine. To construct an appropriate vehicle to encapsulate EXT, an oil‐in‐water single emulsion is generated at 37 °C, which is well above the melting point of the fatty acid but below the denaturation temperature of the peptide drug. The as‐prepared EXT@PC/NEMs are physically stable when stored at 4 °C, as they form a solid core, which prevents drug leakage. Upon their oral delivery at body temperature, the deformable liquid EXT@PC/NEMs may undergo effective cellular uptake, enhancing their permeability across the intestinal epithelium. The orally administered PC/NEMs significantly improve the bioavailability of EXT via intestinal lymphatic transport, ultimately accumulating in the pancreas, suggesting the possibility of orally delivering labile peptide drugs. The delivered EXT may act on pancreatic β‐ and α‐cells to stimulate insulin release and suppress glucagon secretion, respectively, reducing the blood glucose level, eventually having antidiabetic effects. Phase‐changeable nanoemulsions are used to encapsulate a peptide drug during emulsification at 37 °C and are physically stable when stored at 4 °C. Upon oral ingestion at body temperature, the deformable liquid nanoemulsions undergo effective cellular uptake, enhancing their permeability across the intestinal epithelium, ultimately accumulating in the pancreas via lymphatic transport to exert their beneficial antidiabetic effects. [ABSTRACT FROM AUTHOR]