Vimentin Suppresses Inflammation and Tumorigenesis in the Mouse Intestine

The Clinical Relevance of Epithelial-to-Mesenchymal Transition Hallmarks: A Cut-Off-Based Approach in Healthy and Cancerous Cell Lines

The atypical activation of the epithelial-to-mesenchymal transition represents one of the main mechanisms driving cancer cell dissemination. It enables epithelial cancer cells to detach from the primary tumor mass and gain survival advantages in the bloodstream, significantly contributing to the spread of circulating tumor cells. Notably, epithelial-to-mesenchymal transition is not a binary process but rather leads to the formation of a wide range of cell subpopulations characterized by the simultaneous expression of both epithelial and mesenchymal markers. Therefore, analyzing the modulation of EMT hallmarks during the conversion from healthy cells to metastatic cancer cells, which acquire stem mesenchymal characteristics, is of particular interest. This study investigates the expression of a panel of epithelial-to-mesenchymal transition-related genes in healthy cells, primary and metastatic cancer cells, and in mesenchymal cell lines, derived from various tissues, including the lung, colon, pancreas, skin, and neuro-ectoderm, with the aim of identifying potential cut-off values for assessing cancer aggressiveness. Interestingly, we found that the expression levels of CDH1, which encodes the epithelial marker E-cadherin, CDH5, encoding vascular endothelial cadherin, and the epithelial-to-mesenchymal transition-transcription factor ZEB1, effectively distinguished primary from metastatic cancer cells. Additionally, our data suggest a tissue-specific signature in the modulation of epithelial-to-mesenchymal transition markers during cancer progression. Overall, our results underscore the importance of investigating epithelial-to-mesenchymal transition as a tissue-specific process to identify the most suitable markers acting as potential indicators of disease aggressiveness and therapeutic responsiveness.

Towards the Identification of New Biomarkers in Saliva and Serum for Treatment Monitoring of Equine Gastric Ulcer Syndrome: A Liquid Proteomic Approach

Equine gastric ulcer syndrome (EGUS) is a common condition in horses. This study explores the use of liquid proteomics to identify new biomarkers in saliva and serum to monitor EGUS treatment. The proteomes of horses with EGUS before and after a successful treatment with omeprazole were analysed. In saliva, 503 proteins were identified, with 7 upregulated and 6 downregulated post-treatment. Among the proteins that changed, there was an increase in vimentin, linked to wound healing, and a decrease in podocalyxin, associated with tissue damage. In serum, 206 proteins were found, with significant changes in 5. Keratin type I increased, supporting epithelial integrity, whereas immunoglobulin lambda decreased, indicating a reduced immune response. Gene ontology analysis revealed a decrease in immune-related pathways after successful treatment. Overall, 13 proteins in saliva and 5 in serum showed significant changes after treatment, highlighting the differential responses of saliva and serum in EGUS. This report creates new avenues for discovering potential biomarkers to monitor EGUS treatment, which is of high importance for the management of this prevalent disease.

Quercus glauca Acorn Seed Coat Extract Promotes Wound Re-Epithelialization by Facilitating Fibroblast Migration and Inhibiting Dermal Inflammation

The skin, recognized as the largest organ in the human body, serves a vital function in safeguarding against external threats. Severe damage to the skin can pose significant risks to human health. There is an urgent requirement for safe and effective therapies for wound healing. While phytotherapy has been widely utilized for various health conditions, the potential of Quercus glauca in promoting wound healing has not been thoroughly explored. Q. glauca is a cultivated crop known for its abundance of bioactive compounds. This study examined the wound-healing properties of Quercus glauca acorn seed coat water extract (QGASE). The findings from the study suggest that QGASE promotes wound closure in HF cells by upregulating essential markers related to the wound-healing process. Additionally, QGASE demonstrates antioxidant effects, mitigating oxidative stress and aiding in recovery from injuries induced by H2O2. In vivo experiments provide additional substantiation supporting the efficacy of QGASE in enhancing wound healing. The collective results indicate that QGASE may be a promising candidate for the development of innovative therapeutic strategies aimed at enhancing skin wound repair.

Intermediate filaments at a glance

Intermediate filaments (IFs) comprise a large family of versatile cytoskeletal proteins, divided into six subtypes with tissue-specific expression patterns. IFs have a wide repertoire of cellular functions, including providing structural support to cells, as well as active roles in mechanical support and signaling pathways. Consequently, defects in IFs are associated with more than 100 diseases. In this Cell Science at a Glance article, we discuss the established classes of IFs and their general features, their functions beyond structural support, and recent advances in the field. We also highlight their involvement in disease and potential use as clinical markers of pathological conditions. Finally, we provide our view on current knowledge gaps and the future directions of the IF field.

Extracellular vimentin as a versatile immune suppressive protein in cancer

The interest in finding new targets in the tumor microenvironment for anti-cancer therapy has increased rapidly over the years. More specifically, the tumor-associated blood vessels are a promising target. We recently found that the intermediate filament protein vimentin is externalized by endothelial cells of the tumor vasculature. Extracellular vimentin was shown to sustain angiogenesis by mimicking VEGF and supporting cell migration, as well as endothelial cell anergy, the unresponsiveness of the endothelium to proinflammatory cytokines. The latter hampers immune cell infiltration and subsequently provides escape from tumor immunity. Other studies showed that extracellular vimentin plays a role in sustained systemic and local inflammation. Here we will review the reported roles of extracellular vimentin with a particular emphasis on its involvement in the interactions between immune cells and the endothelium in the tumor microenvironment. To this end, we discuss the different ways by which extracellular vimentin modulates the immune system. Moreover, we review how this protein can alter immune cell-vessel wall adhesion by altering the expression of adhesion proteins, attenuating immune cell infiltration into the tumor parenchyma. Finally, we discuss how vimentin-targeting therapy can reverse endothelial cell anergy and promote immune infiltration, supporting anti-tumor immunity.

Proteome Analysis of the Antiproliferative Activity of the Novel Chitooligosaccharide-Gallic Acid Conjugate against the SW620 Colon Cancer Cell Line

Chitooligosaccharide (COS) and gallic acid (GA) are natural compounds with anti-cancer properties, and their conjugate (COS-GA) has several biological activities. Herein, the anti-cancer activity of COS-GA in SW620 colon cancer cells was investigated. MTT assay was used to evaluate cell viability after treatment with 62.5, 122, and 250 µg/mL of COS, GA, and COS-GA for 24 and 48 h. The number of apoptotic cells was determined using flow cytometry. Proteomic analysis was used to explore the mechanisms of action of different compounds. COS-GA and GA showed a stronger anti-cancer effect than COS by reducing SW620 cell proliferation at 125 and 250 µg/mL within 24 h. Flow cytometry revealed 20% apoptosis after COS-GA treatment for 24 h. Thus, GA majorly contributed to the enhanced anti-cancer activity of COS via conjugation. Proteomic analysis revealed alterations in protein translation and DNA duplication in the COS group and the structural constituents of the cytoskeleton, intermediate filament organization, the mitochondrial nucleoid, and glycolytic processes in the COS-GA group. Anti-cancer-activity-related proteins were altered, including CLTA, HSPA9, HIST2H2BF, KRT18, HINT1, DSP, and VIM. Overall, the COS-GA conjugate can serve as a potential anti-cancer agent for the safe and effective treatment of colon cancer.

Cytoplasmic keratins couple with and maintain nuclear envelope integrity in colonic epithelial cells

Keratin intermediate filaments convey mechanical stability and protection against stress to epithelial cells. Keratins are essential for colon health, as seen in keratin 8 knockout (K8-/-) mice exhibiting a colitis phenotype. We hypothesized that keratins support the nuclear envelope and lamina in colonocytes. K8-/- colonocytes in vivo exhibit significantly decreased levels of lamins A/C, B1, and B2 in a colon-specific and cell-intrinsic manner. CRISPR/Cas9- or siRNA-mediated K8 knockdown in Caco-2 cells similarly decreased lamin levels, which recovered after reexpression of K8 following siRNA treatment. Nuclear area was not decreased, and roundness was only marginally increased in cells without K8. Down-regulation of K8 in adult K8flox/flox;Villin-CreERt2 mice following tamoxifen administration significantly decreased lamin levels at day 4 when K8 levels had reduced to 40%. K8 loss also led to reduced levels of plectin, LINC complex, and lamin-associated proteins. While keratins were not seen in the nucleoplasm without or with leptomycin B treatment, keratins were found intimately located at the nuclear envelope and complexed with SUN2 and lamin A. Furthermore, K8 loss in Caco-2 cells compromised nuclear membrane integrity basally and after shear stress. In conclusion, colonocyte K8 helps maintain nuclear envelope and lamina composition and contributes to nuclear integrity.

Mechanotransduction in Skin Inflammation

In the process of mechanotransduction, the cells in the body perceive and interpret mechanical stimuli to maintain tissue homeostasis and respond to the environmental changes. Increasing evidence points towards dysregulated mechanotransduction as a pathologically relevant factor in human diseases, including inflammatory conditions. Skin is the organ that constantly undergoes considerable mechanical stresses, and the ability of mechanical factors to provoke inflammatory processes in the skin has long been known, with the Koebner phenomenon being an example. However, the molecular mechanisms and key factors linking mechanotransduction and cutaneous inflammation remain understudied. In this review, we outline the key players in the tissue's mechanical homeostasis, the available data, and the gaps in our current understanding of their aberrant regulation in chronic cutaneous inflammation. We mainly focus on psoriasis as one of the most studied skin inflammatory diseases; we also discuss mechanotransduction in the context of skin fibrosis as a result of chronic inflammation. Even though the role of mechanotransduction in inflammation of the simple epithelia of internal organs is being actively studied, we conclude that the mechanoregulation in the stratified epidermis of the skin requires more attention in future translational research.