Publications by authors named "Saegwang Park"

Genetically engineered fusion polypeptides have been investigated to introduce unique bio-functionality and improve some therapeutic activity for anti-angiogenesis. We report herein that stimuli-responsive, vascular endothelial growth factor receptor 1 (VEGFR1) targeting fusion polypeptides composed of a VEGFR1 (fms-like tyrosine kinase-1 (Flt1)) antagonist, an anti-Flt1 peptide, and a thermally responsive elastin-based polypeptide (EBP) were rationally designed at the genetic level, biosynthesized, and purified by inverse transition cycling to develop potential anti-angiogenic fusion polypeptides to treat neovascular diseases. A series of hydrophilic EBPs with different block lengths were fused with an anti-Flt1 peptide, forming anti-Flt1-EBPs, and the effect of EBP block length on their physicochemical properties was examined.

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Background: Thrombocytopenia is a common complication in cancer patients undergoing chemotherapy. Chemotherapy-induced thrombocytopenia (CIT) leads to dose reduction and treatment delays, lowering chemotherapy efficacy and survival rate. Thus, rapid recovery and continuous maintenance of platelet count during chemotherapy cycles are crucial in patients with CIT.

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Obese psoriatic patients experience higher disease severity and exhibit poorer treatment responses and clinical outcomes. It has been proposed that proinflammatory cytokines produced by adipose tissue exacerbate psoriasis; however, the role of obesity in psoriasis remains unclear. This study aimed to elucidate the role of obesity in the pathogenesis of psoriasis, focusing on immunological changes.

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We assessed the efficacy of polydeoxyribonucleotide (PDRN) in accelerating the healing of diabetic wounds in a murine model of streptozotocin (STZ)-induced diabetes. After the creation of diabetic wounds, the mice of the PDRN SC, PDRN IP and PBS groups received a subcutaneous, an intra-peritoneal injection of PDRN and a subcutaneous injection of PBS, respectively. After euthanasia, time-dependent changes in the wound diameter and histologic scores were measured and vascular endothelial growth factor (VEGF), transforming growth factor-β1 (TGF-β1) and collagen types I and III were assessed for their expression levels.

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Growing evidence suggests that genetic and epigenetic factors, including environmental factors, contribute to the development of oral squamous cell carcinoma (OSCC). Here, we investigated the transcriptional silencing of the CD24, CD44, CD133, and CD147 genes, which are well-known cancer stem cell surface markers in various cancer types, including OSCC. We first examined the correlation between the transcriptional expression level and reactivation by 5-aza-2′-deoxycytidine (5-aza-dC) and the promoter methylation levels of the four genes in several OSCC cell lines.

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Purpose: The Janus tyrosine kinase and signal transducers and activators of transcription (JAK/STAT) pathway is involved in vascular endothelial growth factor (VEGF) expression, but the role of this pathway in diabetic retinopathy (DR) remains unclear. We investigated the role of the JAK/STAT pathway on DR and VEGF expression using a streptozotocin (STZ)-induced DR mouse model.

Methods: Cultured ARPE-19 cells were exposed to high-glucose conditions and treated with JAK/STAT inhibitors (JAK inhibitor I [JAKiI], tofacitinib, STAT3 inhibitor [STAT3i]) for 48 h.

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Inflammasomes are a group of intracellular multiprotein platforms that play important roles in immune systems. Benzyl isothiocyanate (BITC) is a constituent of cruciferous plants and has been confirmed to exhibit various biological activities. The modulatory effects of BITC on inflammasome-mediated interleukin (IL)-1β expression and its regulatory mechanisms in () LPS/ATP-stimulated THP-1 cells was investigated.

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Human epidermal growth factor receptor type 2 (HER2)-positive breast cancer that is treated with anti-HER2/neu monoclonal antibody (mAb) is not free from late recurrences. Addition of anti-4-1BB mAb to anti-HER2/neu mAb has been demonstrated to strengthen the cytotoxic antitumor response. Our study expands on this by revealing the influence of anti-4-1BB mAb addition on the immune memory of anti-HER2/neu mAb.

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Purpose: The establishment of a preclinical model of the abscopal effect on hepatocellular carcinoma (HCC) and evaluation of whether the hypofractionated radiation therapy (RT) multitumor Hepa1-6 mouse HCC model could be used to suppress nonradiated tumor mass was performed in this study.

Methods And Materials: Hepa1-6 mouse liver cancer cell lines were used to form tumors. Immunogenicity was analyzed using ELISpot and immune cell labeled antibody.

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has been widely used as a traditional medicine in East Asia. Its effects against breast cancer have been reported previously. However, whether -induced breast cancer cell death is immunogenic remains unelucidated.

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Inflammatory bowel disease is known to be associated with a genetic predisposition involving multiple genes; however, there is growing evidence that abnormal interactions with environmental factors, particularly epigenetic factors, can also significantly contribute to the development of inflammatory bowel disease (IBD). Although many genome-wide association studies have been performed to identify the genetic changes underlying the pathogenesis of Crohn's disease, the role of epigenetic alterations based on molecular complications arising from Crohn's disease (CD) is poorly understood. We employed an unbiased approach to define DNA methylation alterations in colonoscopy samples from patients with CD using the HumanMethylation450K BeadChip platform.

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Circadian oscillation is an essential process that influences many physiological and biological mechanisms and a decrease of circadian genes is associated with many diseases such as cancer. Despite many efforts to identify the detailed mechanism for decreasing circadian genes and recovering reduced circadian genes in cancer, it is still largely unknown. We found that BMAL1 was reduced in tumor hypoxia-induced acidosis, and recovered by selectively targeting acidic pH in breast cancer cell lines.

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Background: Pigment epithelium-derived factor (PEDF)-derived 34-mer peptide (PEDF34, Asp-Asn) has anti-angiogenic activity but has limitations in clinical application because of an inverted bell-shaped dose-effect relationship and a short half-life. In this study, we attempted to mitigate these problems by mixing PEDF34 with type I collagen.

Methods: The anti-angiogenic activity of the PEDF34/atelocollagen mixture was evaluated by HUVEC tube formation assay and in a laser-induced choroidal neovascular (CNV) mouse model.

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This study identified chemotherapeutic agents that up-regulate programmed cell death ligand-1 (PD-L1) and galectin-9 (Gal-9) in breast cancer cells. Immunohistochemical (IHC) staining was used to evaluate changes in PD-L1 and Gal-9 expression in the tumor tissue of triple-negative breast cancer (TNBC) patients who received anthracycline- and taxane-based neoadjuvant chemotherapy. To determine whether PD-L1 and Gal-9 expression changes were attributable directly to chemotherapeutics, MDA-MB-231 cells and HS578T cells were treated with different concentrations of anthracycline and taxane.

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Phlorotannins (PTNs), a group of phenolic compounds from seaweeds, have diverse bioactivities. However, there has been no report on their antifibrotic effects during nasal polyp (NP) formation. In the present study, the effect of PTNs on transforming growth factor (TGF)‑β1‑induced profibrotic responses in nasal polyp‑derived fibroblasts (NPDFs) were determined and the relevant signaling pathways were investigated.

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Combination therapies with phosphoinositide 3-kinase (PI3K) inhibitors and trastuzumab (anti-human epidermal growth factor receptor [HER]2/neu antibody) are effective against HER2+ breast cancer. Isoform-selective PI3K inhibitors elicit anti-tumor immune responses that are distinct from those induced by inhibitors of class I PI3K isoforms (pan-PI3K inhibitors). The present study investigated the therapeutic effect and potential for stimulating anti-tumor immunity of combined therapy with an anti-HER2/neu antibody and pan-PI3K inhibitor (GDC-0941) or a PI3K p110α isoform-selective inhibitor (A66) in mouse models of breast cancer.

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Many studies have reported that Aldehyde dehydrogenase 1 (ALDH1) and tumor-infiltrating lymphocytes (TIL) are related to breast cancer prognosis. However, the clinical significance of ALDH1 and tumor-infiltrating immune cells in breast cancer has not been fully investigated in patients who received neoadjuvant chemotherapy (NAC). We studied the significance of the expression of ALDH1 and the population of TIL for predicting the prognosis and chemotherapeutic response of patients with breast cancer who had received NAC.

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Marine algae have valuable health and dietary benefits. The present study aimed to investigate whether an ethanol extract of (CCE) could inhibit the inflammatory response to LPS. CCE attenuated the production of proinflammatory mediators, such as prostaglandin E (PGE) and nitric oxide (NO), by inhibiting inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression in LPS-induced RAW264.

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Marine algae are rich sources of biologically active compounds that may present useful leads in the development of pharmaceuticals, nutraceuticals, and functional foods. The main aim of this study was to identify the possible anti-inflammatory effects of Distromium decumbens in nasal polyp-derived fibroblasts (NPDFs) and its associated mechanism of action. NPDFs were stimulated by Pseudomonas aeruginosa lipopolysaccharide (PA-LPS) and treated with an ethanolic extract of Distromium decumbens (DDE).

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Snail, a zinc-finger transcriptional repressor of E-cadherin expression, is one of the key inducers of epithelial-mesenchymal transition (EMT) in epithelial cancer. In breast cancer, EMT has been associated with malignancies, including metastasis, cancer stem-like properties, and resistance to chemotherapy and radiotherapy. In this study, we analysed the role of Snail in the highly metastatic mesenchymal TUBO‑P2J mouse breast cancer cells, by loss of function using short hairpin RNA.

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The lung is a prototypic organ that was evolved to reduce immunopathology during the immune response to potentially hazardous endogenous and exogenous antigens. In this study, we show that donor CD4 T cells transiently induced expression of indoleamine 2,3-dioxygenase (IDO) in lung parenchyma in an IFN-γ-dependent manner early after allogeneic hematopoietic stem cell transplantation (HSCT). Abrogation of host IDO expression by deletion of the IDO gene or the IFN-γ gene in donor T cells or by FK506 treatment resulted in acute lethal pulmonary inflammation known as idiopathic pneumonia syndrome (IPS).

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Inflammasomes are multi-protein complexes that play a crucial role in innate immune responses. Benzyl isothiocyanate (BITC) is a naturally occurring compound found in cruciferous vegetables, and BITC exhibits potential as a chemopreventive agent. However, whether BITC exerts inflammasome-mediated regulatory effects on neuroinflammation is unknown.

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Hepatitis C virus (HCV) E2 protein binds to CD81, which is a component of the B cell co-stimulatory complex. The E2-CD81 interaction leads to B cell proliferation, protein tyrosine phosphorylation and to the hypermutation of immunoglobulin genes. Epidemiological studies have reported a high prevalence of B cell non-Hodgkin lymphoma (NHL) in HCV-positive patients, suggesting a potential association between HCV and Epstein-Barr virus (EBV) in the genesis of B lymphocyte proliferative disorders.

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Our previous study demonstrated that G-CSF treatment increased the expression of TLR2 in donor grafts; this contributed to rapid engraftment after allogeneic hematopoietic stem cell transplantation (HSCT) in mice. In the current study, we investigated the effects of upregulated TLR2 expression in G-CSF-mobilized donor grafts on acute graft-versus-host disease (GVHD). We found that TLR2 was highly expressed on myeloid cell populations but not T and B cells from the spleens of G-CSF-treated donor mice.

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YCG063 is known as an inhibitor of reactive oxygen species (ROS); however, its intracellular mechanisms of action remain poorly understood. In the present study, we investigated the effects of YCG063 on the inflammatory response of Pseudomonas aeruginosa lipopolysaccharide (PA-LPS)‑stimulated human retinal pigment epithelial cells (RPE cells). Human adult RPE cells (ARPE‑19) were stimulated with PA-LPS.

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