11 research outputs found

    Non-Cytotoxic Photodynamic Therapy with Talaporfin Sodium Reduces the Expression of CXCR4 and Enhances Chemotherapeutic Efficacy in Undifferentiated Gastric Cancer Cell Line HGC27

    Get PDF
    Gastric cancer (GC), particularly the undifferentiated type, is frequently associated with peritoneal metastasis, which significantly worsens prognosis due to its resistance to conventional treatments. Photodynamic therapy (PDT) is localized treatment using a photosensitizer (PS) activated by light of a specific wavelength to generate cytotoxic reactive oxygen species that induce cell death. Severe adverse events were reported from clinical trials investigating PDT for peritoneal dissemination conducted until the early 2000s, leaving its safety and clinical effectiveness unestablished. The present study explored whether “non-cytotoxic” PDT using talaporfin sodium (TS) could enhance efficacy of chemotherapeutic agents in undifferentiated GC cell line HGC27. Cell viability was evaluated with MTT assay following TS-PDT, and the synergistic effect between non-cytotoxic TS-PDT and anticancer drug SN-38 was assessed. Changes in expression of drug resistance markers were analyzed through qRT-PCR, Western blotting, and immunocytochemistry. We found that non-cytotoxic TS-PDT enhanced the efficacy of chemotherapy in the undifferentiated GC cell line and reduced the expression of C-X-C chemokine receptor type 4, a key marker associated with GC stem-like properties. These findings highlight the potential of non-cytotoxic TS-PDT as a synergistic treatment approach. We conclude that non-cytotoxic TS-PDT could enhance drug sensitivity and offers a promising therapeutic strategy for GC

    Spatiotemporal expression of HMGB2 regulates cell proliferation and hepatocyte size during liver regeneration

    Get PDF
    Liver regeneration is an extraordinarily complex process involving a variety of factors; however, the role of chromatin protein in hepatocyte proliferation is largely unknown. In this study, we investigated the functional role of high-mobility group box 2 (HMGB2), a chromatin protein in liver regeneration using wild-type and HMGB2-knockout (KO) mice. Liver tissues were sampled after 70% partial hepatectomy (PHx), and analyzed by immunohistochemistry, western blotting and flow cytometry using various markers of cell proliferation. In WT mice, hepatocyte proliferation was strongly correlated with the spatiotemporal expression of HMGB2; however, cell proliferation was significantly delayed in hepatocytes of HMGB2-KO mice. Quantitative PCR demonstrated that cyclin D1 and cyclin B1 mRNAs were significantly decreased in HMGB2-KO mice livers. Interestingly, hepatocyte size was significantly larger in HMGB2-KO mice at 36–72 h after PHx, and these results suggest that hepatocyte hypertrophy appeared in parallel with delayed cell proliferation. In vitro experiments demonstrated that cell proliferation was significantly decreased in HMGB2-KO cells. A significant delay in cell proliferation was also found in HMGB2-siRNA transfected cells. In summary, spatiotemporal expression of HMGB2 is important for regulation of hepatocyte proliferation and cell size during liver regeneration.Citation: Yano K, Choijookhuu N, Ikenoue M, Fidya, Fukaya T, Sato K, Lee D, Taniguchi N, Chosa E, Nanashima A, Hishikawa Y. Spatiotemporal expression of HMGB2 regulates cell proliferation and hepatocyte size during liver regeneration. Sci Rep. 2022 Jul 13;12(1):11962. doi: 10.1038/s41598-022-16258-4. PMID: 35831365; PMCID: PMC9279446

    SETDB1-Mediated Chromatin Regulation in Intestinal Epithelial Cells During Intestinal Ischemia-Reperfusion Injury

    Get PDF
    SET domain bifurcated 1 (SETDB1), a histone H3K9-specific methyltransferase, is crucial for heterochromatin formation and intestinal homeostasis, but its role in intestinal ischemia-reperfusion injury (IRI) remains unclear. This study investigated changes in SETDB1-mediated nuclear chromatin regulation in intestinal epithelial cells (IECs) using an IRI mouse model. Jejunal samples were collected after 75 min of ischemia followed by 24 hr of reperfusion. Sinefungin was administered as a histone methyltransferase inhibitor. Morphologic changes were evaluated using hematoxylin-eosin staining and electron microscopy, and cell-adhesion molecule expression, including ZO-1, E-cadherin, integrin-β4, and laminin, was evaluated using immunohistochemistry. Super-resolution microscopy analyzed intranuclear SETDB1 localization and heterochromatin formation in IECs. IRI-affected jejunum exhibited massive IEC detachment, dilated intercellular spaces, basement membrane damage, and decreased expression of E-cadherin and integrin-β4. Sinefungin prevented these changes, however. The proportion of IECs expressing nuclear SETDB1 throughout the euchromatin was significantly higher in IRI-affected jejunum (77.8%) than sham-treated (3.0%) or sinefungin-treated, IRI-affected jejunum (2.7%). The proportion of IECs with decreased heterochromatin was significantly higher in sinefungin-treated, IRI-affected jejunum (84.3%) than untreated IRI-affected jejunum (15.6%). These findings suggest that SETDB1-mediated chromatin regulation is pivotal in intestinal IRI and represents a potential therapeutic target

    Spatiotemporal expression of HMGB2 regulates cell proliferation and hepatocyte size during liver regeneration

    No full text
    Liver regeneration is an extraordinarily complex process involving a variety of factors; however, the role of chromatin protein in hepatocyte proliferation is largely unknown. In this study, we investigated the functional role of high-mobility group box 2 (HMGB2), a chromatin protein in liver regeneration using wild-type and HMGB2-knockout (KO) mice. Liver tissues were sampled after 70% partial hepatectomy (PHx), and analyzed by immunohistochemistry, western blotting and flow cytometry using various markers of cell proliferation. In WT mice, hepatocyte proliferation was strongly correlated with the spatiotemporal expression of HMGB2; however, cell proliferation was significantly delayed in hepatocytes of HMGB2-KO mice. Quantitative PCR demonstrated that cyclin D1 and cyclin B1 mRNAs were significantly decreased in HMGB2-KO mice livers. Interestingly, hepatocyte size was significantly larger in HMGB2-KO mice at 36–72 h after PHx, and these results suggest that hepatocyte hypertrophy appeared in parallel with delayed cell proliferation. In vitro experiments demonstrated that cell proliferation was significantly decreased in HMGB2-KO cells. A significant delay in cell proliferation was also found in HMGB2-siRNA transfected cells. In summary, spatiotemporal expression of HMGB2 is important for regulation of hepatocyte proliferation and cell size during liver regeneration.Citation: Yano K, Choijookhuu N, Ikenoue M, Fidya, Fukaya T, Sato K, Lee D, Taniguchi N, Chosa E, Nanashima A, Hishikawa Y. Spatiotemporal expression of HMGB2 regulates cell proliferation and hepatocyte size during liver regeneration. Sci Rep. 2022 Jul 13;12(1):11962. doi: 10.1038/s41598-022-16258-4. PMID: 35831365; PMCID: PMC9279446
    corecore