• Title/Summary/Keyword: microenvironment

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Cholinergic and Neurokinergic Agonist-induced $Ca^{2+}$ Responses in Rat von Ebner's Gland Acinar Cells

  • Chung, Ki-Myung;Kim, Sang-Hee;Cho, Young-Kyung;Roper, Stephen D.;Kim, Kyung-Nyun
    • International Journal of Oral Biology
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    • v.31 no.3
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    • pp.99-105
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    • 2006
  • Von Ebner's glands (vEG) are minor salivary glands associated with circumvallate and foliate papilla. The secretions of vEG consist of microenvironment of the taste buds in the circumvallate and foliate papillae, and thus saliva from vEG plays a role in the perception of taste. The $Ca^{2+}$ signaling system in rat vEG acinar cell was examined using the $Ca^{2+}$-sensitive fluorescent indicator Fura-2. Agonist-induced increase in intracellular $Ca^{2+}\;([Ca^{2+}]_i)$ was stimulated by carbachol (CCh) and substance P (SP), but not by norepinephrine (NE), and recovered to control levels by their receptor antagonists dose-dependently. The effects were also observed in $Ca^{2+}$-free medium, suggesting mobilization from intracellular $Ca^{2+}$ store. These results in the vEG acinar cell indicate that 1) $[Ca^{2+}]_i$ is at least regulated by muscarinic and neurokininergic (NK1) receptors; 2) the increases in $[Ca^{2+}])i$ activated by CCh and SP are mainly mediated by discharge of cytosolic calcium pool.

Hypoxic Microenvironmental Control of Stress Protein and Erythropoietin Gene Expression

  • Beak, Sun-Hee;Han, Mi-Young;Lee, Seung-Hoon;Choi, Eun-Mi;Park, Young-Mee
    • BMB Reports
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    • v.32 no.2
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    • pp.112-118
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    • 1999
  • The presence of hypoxic cells in solid tumors has long been considered a problem in cancer treatment such as in radiation therapy or treatment with some anticancer drugs. It has been suggested that hypoxic cells are involved in the development of a more aggressive phenotype and contribute to metastasis. In this study, as an attempt to understand how tumor cells adapt to hypoxic stress, we investigated the regulation of the hypoxia-induced expression of proteins that control essential processes of tumor cell survival and angiogenesis. We first examined whether hypoxia induces stress protein gene expression of murine solid tumor RIF cells. We also examined hypoxia-induced changes in angiogenic gene expression in these cells. Finally, we investigated the association of the elevated levels of stress proteins with the regulation of hypoxia-induced angiogenic gene expression. Results demonstrated that hypoxia induced the expression of the erythropoietin (EPO) gene and at least two major members of stress proteins, heat shock protein 70 (HSP70) and 25 (HSP25) in RIF tumor cells. Evidence that the expression of EPO gene was greatly potentiated in TR cells suggested that the elevated levels of HSPs may play an important role in the regulation of the hypoxia-induced EPO gene expression. One of the RIF variant cell lines, TR, displays elevated levels of HSPs constitutively. Taken together, our results suggest that a hypoxic tumor microenvironment may promote the survival and malignant progression of the tumor cells by temporarily increasing the level of stress proteins and expressing angiogenic genes. We suspect that stress proteins may be associated with the increase of the angiogenic potential of tumor cells under hypoxia.

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Changes of Plasminogen Activator Activity under Heat Stress Condition in Porcine Endometrium

  • Hwangbo, Yong;Cheong, Hee-Tae;Park, Choon-Keun
    • Journal of Animal Reproduction and Biotechnology
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    • v.34 no.3
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    • pp.240-246
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    • 2019
  • The aim of this study was to investigate effect of heat stress on expression levels of plasminogen activators (PAs) related mRNAs and proteins, and changes of PAs activity in porcine endometrial explants. The endometrial explants (200 ± 50 mg) were isolated from middle part of uterine horn at follicular phase (Day 19-21) and were pre-incubated in serum-free culture medium at 38.5℃ in 5% CO2 for 18 h. Then, the tissues were transferred into fresh medium and were cultured at different temperature (38.5, 39.5, 40.5 or 41.5℃) for 24 h. The expression level of urokinase-type PA (uPA), type-1 PA inhibitor (PAI-1), type-2 PAI (PAI-2), and heat shock protein-90 (HSP-90) mRNA were analysis by reverse-transcription PCR and proteins were measured by western blotting. The supernatant were used for measurement of PAs activity. In results, mRNA and protein levels of HSP-90 was higher in 41.5℃ treatment groups than other treatment groups (p < 0.05). The expression of uPA, PAI-1, and PAI-2 mRNA were slightly increased by heat stress, however, there were no significant difference. Heat stress condition suppressed expression of active uPA and PAI-2 proteins (p < 0.05), whereas PAI-1 protein was increased (p < 0.01). Although PAI-1 protein was increased and active uPA was decreased, PAs activity was greatly enhanced by exposure of heat stress (p < 0.05). These results suggest that heat stress condition could change intrauterine microenvironment through regulation of PAs activity and other factors regarding with activation of PAs might be regulate by heat stress. Therefore, more studies regarding with regulatory mechanism of PAs activation are needed.

Infectivity of Orientia tsutsugamushi to Various Eukaryotic Cells and Their Cellular Invasion Mechanism (Orientia tsutsugamushi의 유핵세포내 감염능 분석 및 기전)

  • Ihn, Kyung-Soo;Han, Seung-Hoon;Kim, Hang-Rae;Seong, Seung-Yong;Kim, Ik-Sang;Choi, Myung-Sik
    • The Journal of the Korean Society for Microbiology
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    • v.34 no.5
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    • pp.435-443
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    • 1999
  • Orientia tsutsugamushi is obligate intracellular bacterium that grows within the cytoplasm of the eukaryotic host cells. Therefore capability of the attachment, entry into the host cell and intracellular survival should be critical process for oriential infection. In this study we investigated the cellular invasion mechanism of Orientia tsutsugamushi and the role of transmembrane heparan sulfate proteoglycan, which binds diverse components at the cellular microenvironment and is implicated as host cell receptors for a variety of microbial pathogens. First of all Orientia tsutsugamushi can invade a wide range of nonprofessional phagocytic cells including fibroblast, epithelial cells and endothelial cells of various host species, including Band T lymphocytes. Thus, it was postulated that the attachment of O. tsutsugamushi requires the recognition of ubiquitous surface structures of many kinds of host cells. Treatments with heparan sulfate and heparin inhibited the infection of Orientia tsutsugamushi in dose-dependent manner for L cell, mouse fibroblast, whereas other glycosaminoglycans such as chondroitin sulfate had no effect. Collectively, these findings provide strong evidence that initial interaction with heparan sulfate proteoglycan is required for the oriential invasion into host cells.

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Ethyl Acetate Fraction of Adenophora triphylla var. japonica Inhibits Migration of Lewis Lung Carcinoma Cells by Suppressing Macrophage Polarization toward an M2 Phenotype

  • Park, Shin-Hyung
    • Journal of Pharmacopuncture
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    • v.22 no.4
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    • pp.253-259
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    • 2019
  • Objectives: It is reported that tumor-associated macrophages (TAMs) contribute to cancer progression by promoting tumor growth and metastasis. The purpose of this study is to investigate the effect of different fractions of Adenophora triphylla var. japonica (AT) on the polarization of macrophages into the M2 phenotype, a major phenotype of TAMs. Methods: We isolated hexane, ethyl acetate, and butanol fractions from crude ethanol extract of AT. The cytotoxicity of AT in RAW264.7 cells was examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. RAW264.7 cells were polarized into the M2 phenotype by treatment with interleukin (IL)-4 and IL-13. The expression of M2 macrophage marker genes was detected by reverse transcription polymerase chain reaction (RT-PCR). The phosphorylation level of signal transducer and activator of transcription 6 (STAT6) was investigated by western blot analysis. The migration of Lewis lung carcinoma (LLC) cells was examined by transwell migration assay using conditioned media (CM) collected from RAW264.7 cells as a chemoattractant. Results: Among various fractions of AT, the ethyl acetate fraction of AT (EAT) showed the most significant suppressive effect on the mRNA expression of M2 macrophage markers, including arginase-1, interleukin (IL)-10 and mannose receptor C type 1 (MRC-1), up-regulated by treatment of IL-4 and IL-13. In addition, EAT suppressed the phosphorylation of STAT6, a critical regulator of IL-4 and IL-13-induced M2 macrophage polarization. Finally, the increased migration of Lewis lung carcinoma (LLC) cells by CM from M2-polarized RAW264.7 cells was reduced by CM from RAW264.7 cells co-treated with EAT and M2 polarization inducers. Conclusion: We demonstrated that EAT attenuated cancer cell migration through suppression of macrophage polarization toward the M2 phenotype. Additional preclinical or clinical researches are needed to evaluate its regulatory effects on macrophage polarization and anti-cancer activities.

Enhanced macrophage uptake of radiolabeled liposome triggered by ginseng extracts

  • Lee, Woonghee;Rhee, Man Hee;Yoo, Jeongsoo
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.5 no.2
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    • pp.113-119
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    • 2019
  • During tumor progression various immunosuppressive cells are recruited to a tumor microenvironment (TME). Tumor-associated macrophages (TAMs) are particularly abundant in TME. Based on their function, macrophages are categorized into two phenotypes: tumoricidal M1 and tumor-supportive M2. Generally, TAMs closely resemble M2-macrophages and lead to tumor growth. However, their phenotype can be changed by immune activator from M2 to M1 and thus promote tumor immunotherapy. Ginseng extracts are well known for its anti-tumor and anti-inflammatory effects from numerous reported studies. However, the mechanism of their effects is still not clear. Recently, some studies suggested that ginseng extracts induced immune activation as well as anti-tumor activities by a repolarization of activated macrophage from M2 phenotype to M1 phenotype. But, further verification about the mechanism as to how ginseng extracts can stimulate the immune response is still needed. In this study, we investigated whether ginseng extracts can alter the phenotype from M2 macrophages to M1 macrophages in mice by using a radiolabeled liposome. And we also evaluated the potential of radiolabeled liposome as a nuclear imaging agent to monitor the transition of phenotype of TAMs. In conclusion, the ginseng extracts seem to change the phenotype of macrophages from M2 to M1 like as lipopolysaccharide (LPS) in mice.

Long-Duration Three-Dimensional Spheroid Culture Promotes Angiogenic Activities of Adipose-Derived Mesenchymal Stem Cells

  • Lee, Jun Hee;Han, Yong-Seok;Lee, Sang Hun
    • Biomolecules & Therapeutics
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    • v.24 no.3
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    • pp.260-267
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    • 2016
  • Mesenchymal stem cells (MSCs) offer significant therapeutic promise for various regenerative therapies. However, MSC-based therapy for injury exhibits low efficacy due to the pathological environment in target tissues and the differences between in vitro and in vivo conditions. To address this issue, we developed adipose-derived MSC spheroids as a novel delivery method to preserve the stem cell microenvironment. MSC spheroids were generated by suspension culture for 3 days, and their sizes increased in a time-dependent manner. After re-attachment of MSC spheroids to the plastic dish, their adhesion capacity and morphology were not altered. MSC spheroids showed enhanced production of hypoxia-induced angiogenic cytokines such as vascular endothelial growth factor (VEGF), stromal cell derived factor (SDF), and hepatocyte growth factor (HGF). In addition, spheroid culture promoted the preservation of extracellular matrix (ECM) components, such as laminin and fibronectin, in a culture time- and spheroid size-dependent manner. Furthermore, phosphorylation of AKT, a cell survival signal, was significantly higher and the expression of pro-apoptotic molecules, poly (ADP ribose) polymerase-1 (PARP-1) and cleaved caspase-3, was markedly lower in the spheroids than in MSCs in monolayers. In the murine hindlimb ischemia model, transplanted MSC spheroids showed better proliferation than MSCs in monolayer. These findings suggest that MSC spheroids promote MSC bioactivities via secretion of angiogenic cytokines, preservation of ECM components, and regulation of apoptotic signals. Therefore, MSC spheroid-based cell therapy may serve as a simple and effective strategy for regenerative medicine.

Polarization of M2 Macrophages by Interaction between Prostate Cancer Cells Treated with Trichomonas vaginalis and Adipocytes

  • Chung, Hyo-Yeoung;Kim, Jung-Hyun;Han, Ik-Hwan;Ryu, Jae-Sook
    • Parasites, Hosts and Diseases
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    • v.58 no.3
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    • pp.217-227
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    • 2020
  • Trichomonas vaginalis causes inflammation of the prostate and has been detected in tissues of prostate cancers (PCa), prostatitis and benign prostatic hyperplasia. Obesity is a risk factor for PCa and causes a chronic subclinical inflammation. This chronic inflammation further exacerbates adipose tissue inflammation as results of migration and activation of macrophages. Macrophages are the most abundant immune cells in the PCa microenvironment. M2 macrophages, known as Tumor-Associated Macrophages, are involved in increasing cancer malignancy. In this study, conditioned medium (TCM) of PCa cells infected with live trichomonads contained chemokines that stimulated migration of the mouse preadipocytes (3T3-L1 cells). Conditioned medium of adipocytes incubated with TCM (ATCM) contained Th2 cytokines (IL-4, IL-13). Macrophage migration was stimulated by ATCM. In macrophages treated with ATCM, expression of M2 markers increased, while M1 markers decreased. Therefore, it is suggested that ATCM induces polarization of M0 to M2 macrophages. In addition, conditioned medium from the macrophages incubated with ATCM stimulates the proliferation and invasiveness of PCa. Our findings suggest that interaction between inflamed PCa treated with T. vaginalis and adipocytes causes M2 macrophage polarization, so contributing to the progression of PCa.

Extracranial systemic antitumor response through the abscopal effect induced by brain radiation in a patient with metastatic melanoma

  • D'Andrea, Mark A.;Reddy, G.K.
    • Radiation Oncology Journal
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    • v.37 no.4
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    • pp.302-308
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    • 2019
  • The abscopal effect is a term that has been used to describe the phenomenon in which localized radiation therapy treatment of a tumor lesion triggers a spontaneous regression of metastatic lesion(s) at a non-irradiated distant site(s). Radiation therapy induced abscopal effects are believed to be mediated by activation and stimulation of the immune system. However, due to the brain's distinctive immune microenvironment, extracranial abscopal responses following cranial radiation therapy have rarely been reported. In this report, we describe the case of 42-year-old female patient with metastatic melanoma who experienced an abscopal response following her cranial radiation therapy for her brain metastasis. The patient initially presented with a stage III melanoma of the right upper skin of her back. Approximately 5 years after her diagnosis, the patient developed a large metastatic lesion in her upper right pectoral region of her chest wall and axilla. Since the patient's tumor was positive for BRAF and MEK, targeted therapy with dabrafenib and trametinib was initiated. However, the patient experienced central nervous system (CNS) symptoms of headache and disequilibrium and developed brain metastases prior to the start of targeted therapy. The patient received radiation therapy to a dose of 30 Gy delivered in 15 fractions to her brain lesions while the patient was on dabrafenib and trametinib therapy. The patient's CNS metastases improved significantly within weeks of her therapy. The patient's non-irradiated large extracranial chest mass and axilla mass also shrank substantially demonstrating the abscopal effect during her CNS radiation therapy. Following radiation therapy of her residual chest lesions, the patient was disease free clinically and her CNS lesions had regressed. However, when the radiation therapy ended and the patient continued her targeted therapy alone, recurrence outside of her previously treated fields was noted. The disease recurrence could be due to the possibility of developing BRAF resistance clones to the BRAF targeted therapy. The patient died eventually due to wide spread systemic disease recurrence despite targeted therapy.

Application of a paste-type acellular dermal matrix for coverage of chronic ulcerative wounds

  • Jeon, Minseok;Kim, So Young
    • Archives of Plastic Surgery
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    • v.45 no.6
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    • pp.564-571
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    • 2018
  • Background Chronic wounds occur due to failure of the normal healing process, associated with a lack of deposition of cellular components and a suitable microenvironment such as the extracellular matrix (ECM). Acellular dermal matrix (ADM) is viewed as an ECM substitute, and a paste-type ADM has recently been introduced. We hypothesized that CGPaste, an injectable paste-type ADM, could serve as a scaffold and promote wound healing. Methods We retrospectively studied seven patients in whom CGPaste was applied between 2017 and 2018, who had pressure ulcers, necrotizing fasciitis, diabetic foot ulcers, traumatic defects, and osteomyelitis. The goal of applying CGPaste was to achieve complete wound healing with re-epithelialization or growth of granulation tissue, depending upon the wound bed status. CGPaste was injected based on the wound size along with the application of a dressing. Results Four of the seven patients showed granulation tissue on their wound bed, while the other three patients had a bony wound bed. The mean wound area was $453.57mm^2$ and the depth was 10.71 mm. Wound healing occurred in five of the seven patients (71.43%). The mean duration of complete healing was 2.4 weeks. Two patients showed failure due to paste absorption (29.57%); these patients had wound beds comprising bone with relatively large and deep wounds ($40{\times}30$ and $30{\times}20mm^2$ in area and 15 and 10 mm in depth). Conclusions CGPaste is an effective option for coverage of small and deep chronic wounds for which a flap operation or skin grafting is unfeasible.