Publications by authors named "Ka Y Fung"

Pancreatic ductal adenocarcinoma (PDAC) is a lethal solid malignancy with many patients succumbing to the disease within 6 months of diagnosis. The mechanisms that underlie PDAC initiation and progression are poorly understood. Current treatment options are primarily limited to chemotherapy, which is often provided with palliative intent.

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Interferon epsilon (IFNε) is a unique type I interferon (IFN) that shows distinct constitutive expression in reproductive tract epithelium. Understanding how IFNε expression is regulated is critical for the mechanism of action in protecting the mucosa from infection. Combined computational and experimental investigation of the promoter of IFNε predicted transcription factor binding sites for the ETS family of transcription factors.

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Interleukin (IL-)11, an IL-6 family cytokine, has pivotal roles in autoimmune diseases, fibrotic complications, and solid cancers. Despite intense therapeutic targeting efforts, structural understanding of IL-11 signalling and mechanistic insights into current inhibitors are lacking. Here we present cryo-EM and crystal structures of the human IL-11 signalling complex, including the complex containing the complete extracellular domains of the shared IL-6 family β-receptor, gp130.

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The utilization of preclinical murine models of colorectal cancer (CRC) has been essential to our understanding of the onset and progression of disease. As the genetic complexity of these models evolves to better recapitulate emerging CRC subtypes, our ability to utilize these models to discover and validate novel therapeutic targets will also improve. This will be aided, in part, by the development of live animal imaging techniques, including confocal endomicroscopy for mice.

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Epithelial-mesenchymal transition (EMT) is a continuum that includes epithelial, partial EMT, and mesenchymal states, each of which is associated with cancer progression, invasive capabilities, and ultimately, metastasis. We used a lineage-traced sporadic model of pancreatic cancer to generate a murine organoid biobank from primary and secondary tumors, including sublines that underwent partial EMT and complete EMT. Using an unbiased proteomics approach, we found that organoid morphology predicts the EMT state, and the solid organoids are associated with a partial EMT signature.

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Article Synopsis
  • This study investigates how the gut virome (the collection of viruses in the gut) changes in mice as they develop colorectal cancer (CRC) induced by a chemical called azoxymethane (AOM).
  • The researchers observed that as the mice aged, the number and size of tumors increased, with the first tumors appearing at week 12 in the AOM group, showcasing a significant decrease in viral diversity and a shift in viral profiles at this time.
  • They identified specific viruses that are either positively or negatively associated with tumor growth, suggesting that changes in the gut virome, particularly involving bacteriophages, may play a role in the development of colorectal neoplasia.
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Interleukin-11 (IL-11) is a cytokine that has been strongly implicated in the pathogenesis of fibrotic diseases and solid malignancies. Elevated IL-11 expression is also associated with several non-malignant inflammatory diseases where its function remains less well-characterized. Here, we summarize current literature surrounding the contribution of IL-11 to the pathogenesis of autoimmune inflammatory diseases, including rheumatoid arthritis, multiple sclerosis, diabetes and systemic sclerosis, as well as other chronic inflammatory conditions such as periodontitis, asthma, chronic obstructive pulmonary disease, psoriasis and colitis.

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Chronic inflammation of the large intestine is associated with an increased risk of developing colorectal cancer (CRC), the second most common cause of cancer-related deaths worldwide. Necroptosis has emerged as a form of lytic programmed cell death that, distinct from apoptosis, triggers an inflammatory response. Dysregulation of necroptosis has been linked to multiple chronic inflammatory diseases, including inflammatory bowel disease and cancer.

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Interleukin (IL)-18, a member of the IL-1 family of cytokines, has emerged as a key regulator of mucosal homeostasis within the gastrointestinal tract. Like other members of this family, IL-18 is secreted as an inactive protein and is processed into its active form by caspase-1, although other contributors to precursor processing are emerging.Numerous studies have evaluated the role of IL-18 within the gastrointestinal tract using genetic or complementary pharmacological tools and have revealed multiple roles in tumorigenesis.

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This study was to examine the kinematics, muscle activities, and perceived physical exertion in different regions of the spine during patient transfers by nursing students between a bed and a wheelchair, with or without a transfer belt in a laboratory setting. Results showed that with the effect of the belt, the % maximum voluntary contraction of the lumbar erector spinae was reduced significantly by nearly 10%. Muscle activity was significantly increased in thoracic erector and multifidus spinae during wheelchair-to-bed transfer, compared to bed-to-wheelchair transfers.

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Gastrointestinal epithelial cells provide a selective barrier that segregates the host immune system from luminal microorganisms, thereby contributing directly to the regulation of homeostasis. We have shown that from early embryonic development Bcl-G, a Bcl-2 protein family member with unknown function, was highly expressed in gastrointestinal epithelial cells. While Bcl-G was dispensable for normal growth and development in mice, the loss of Bcl-G resulted in accelerated progression of colitis-associated cancer.

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We have examined the influence of depleting plasmacytoid dendritic cells (pDC) in mice on the immune response to the gut pathogen , an organism that is a model for human attaching effacing pathogens such as enterohaemorraghic . A significantly higher number of were found in mice depleted of pDC from 7 days after infection and pDC depleted mice showed increased gut pathology and higher levels of mRNA encoding inflammatory cytokines in the colon upon infection. pDC-depletion led to a compromising of the gut mucosal barrier that may have contributed to increased numbers of in systemic organs.

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Chemical probes of epigenetic 'readers' of histone post-translational modifications (PTMs) have become powerful tools for mechanistic and functional studies of their target proteins in normal physiology and disease pathogenesis. Here we report the development of the first class of chemical probes of YEATS domains, newly identified 'readers' of histone lysine acetylation (Kac) and crotonylation (Kcr). Guided by the structural analysis of a YEATS-Kcr complex, we developed a series of peptide-based inhibitors of YEATS domains by targeting a unique π-π-π stacking interaction at the proteins' Kcr recognition site.

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A single layer of epithelial cells separates luminal antigens from the host immune system throughout the gastrointestinal tract. A breakdown in the integrity of the epithelial barrier can lead to chronic inflammation, which is associated with numerous complications including cancer. Here we describe three experimental protocols to chemically induce acute and chronic inflammatory bowel disease (IBD) symptoms and colitis-associated colorectal cancer (CRC) progression.

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Inflammasomes are key regulators of innate immunity in chronic inflammatory disorders and autoimmune diseases, but their role in inflammation-associated tumorigenesis remains ill-defined. Here we reveal a protumorigenic role in gastric cancer for the key inflammasome adaptor apoptosis-related speck-like protein containing a CARD (ASC) and its effector cytokine IL18. Genetic ablation of ASC in the spontaneous mouse model of intestinal-type gastric cancer suppressed tumorigenesis by augmenting caspase-8-like apoptosis in the gastric epithelium, independently from effects on myeloid cells and mucosal inflammation.

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The type I interferons (IFNs) are a family of cytokines with diverse biological activities, including antiviral, antiproliferative, and immunoregulatory functions. The discovery of the hormonally regulated, constitutively expressed IFNϵ has suggested a function for IFNs in reproductive tract homeostasis and protection from infections, but its intrinsic activities are untested. We report here the expression, purification, and functional characterization of murine IFNϵ (mIFNϵ).

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Innate lymphoid cells (ILCs) contribute to the regulation of gastrointestinal (GI) homeostasis. Over the past 15 years, there has been a large effort to dissect the mechanisms required for GI homeostasis, with a major focus on different immune cell populations and the cytokines that they produce. In contrast to T-helper (Th) cells, ILCs respond rapidly to cytokines in their microenvironment in the absence of specific antigens; however, once activated both cell populations have similar effector functions.

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is a common etiological agent of pediatric osteoarticular infections. While current research has expanded our understanding of pathogenesis, there is a paucity of knowledge about host-pathogen interactions and virulence gene regulation. Many host-adapted bacterial pathogens contain phase variable DNA methyltransferases ( genes), which can control expression of a regulon of genes (phasevarion) through differential methylation of the genome.

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In this study, the capability of using aerobic granules to undergo simultaneous anaerobic decolorization and aerobic aromatic amines degradation was demonstrated for azo dye wastewater treatment. An integrated acclimation-granulation process was devised, with Mordant Orange 1 as the model pollutant. Performance tests were carried out in a batch column reactor to evaluate the effect of various operating parameters.

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Legionella pneumophila is the causative agent of Legionnaires' disease, a potentially fatal lung infection. Alveolar macrophages support intracellular replication of L. pneumophila, however the contributions of other immune cell types to bacterial killing during infection are unclear.

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Enteropathogenic Escherichia coli (EPEC) interferes with host cell signaling by injecting virulence effector proteins into enterocytes via a type III secretion system (T3SS). NleB1 is a novel T3SS glycosyltransferase effector from EPEC that transfers a single N-acetylglucosamine (GlcNAc) moiety in an N-glycosidic linkage to Arg(117) of the Fas-associated death domain protein (FADD). GlcNAcylation of FADD prevents the assembly of the canonical death-inducing signaling complex and inhibits Fas ligand (FasL)-induced cell death.

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Article Synopsis
  • Type I interferons, especially interferon-β (IFN-β), play a crucial role in immune responses against pathogens and tumors.
  • Unlike other interferons, IFN-β interacts specifically with the IFNAR1 receptor without needing IFNAR2, which is a novel finding.
  • This unique IFNAR1-IFN-β interaction influences gene expression through different pathways, and experiments show that signaling via IFNAR1 is important for managing sepsis in mice, highlighting its potential therapeutic relevance.
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The innate immune system senses pathogens through pattern-recognition receptors (PRRs) that signal to induce effector cytokines, such as type I interferons (IFNs). We characterized IFN-ε as a type I IFN because it signaled via the Ifnar1 and Ifnar2 receptors to induce IFN-regulated genes. In contrast to other type I IFNs, IFN-ε was not induced by known PRR pathways; instead, IFN-ε was constitutively expressed by epithelial cells of the female reproductive tract (FRT) and was hormonally regulated.

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The mucosal system is the first line of defense against many pathogens. It is continuously exposed to dietary and microbial antigens, and thus the host must maintain a homeostatic environment between commensal microbiota and pathogenic infections. Following infections and inflammatory events, a rapid innate immune response is evoked to dampen the inflammatory processes.

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