Reprogramming of cancer-associated fibroblasts by apoptotic cancer cells inhibits lung metastasis via Notch1-WISP-1 signaling.

The interplay between apoptotic cancer cells and the tumor microenvironment modulates cancer progression and metastasis. Cancer-associated fibroblasts (CAFs) play a crucial role in promoting these events through paracrine communication. Here, we demonstrate that conditioned medium (CM) from lung CAFs exposed to apoptotic cancer cells suppresses TGF-ß1-induced migration and invasion of cancer cells and CAFs. Direct exposure of CAFs to apoptotic 344SQ cells (ApoSQ) inhibited CAF migration and invasion and the expression of CAF activation markers. Enhanced secretion of Wnt-induced signaling protein 1 (WISP-1) by CAFs exposed to ApoSQ was required for these antimigratory and anti-invasive effects. Pharmacological inhibition of Notch1 activation or siRNA-mediated Notch1 silencing prevented WISP-1 production by CAFs and reversed the antimigratory and anti-invasive effects. Enhanced expression of the Notch ligand delta-like protein 1 on the surface of ultraviolet-irradiated apoptotic lung cancer cells triggered Notch1-WISP-1 signaling. Phosphatidylserine receptor brain-specific angiogenesis inhibitor 1 (BAI1)-Rac1 signaling, which facilitated efferocytosis by CAFs, participated in crosstalk with Notch1 signaling for optimal production of WISP-1. In addition, a single injection of ApoSQ enhanced WISP-1 production, suppressed the expression of CAF activation markers in isolated Thy1+ CAFs, and inhibited lung metastasis in syngeneic immunocompetent mice via Notch1 signaling. Treatment with CM from CAFs exposed to ApoSQ suppressed tumor growth and lung metastasis, whereas treatment with WISP-1-immunodepleted CM from CAFs exposed to ApoSQ reversed the antitumorigenic and antimetastatic effects. Therefore, treatment with CM from CAFs exposed to apoptotic lung cancer cells could be therapeutically applied to suppress CAF activation, thereby preventing cancer progression and metastasis.

RhoA-Dependent HGF and c-Met Mediate Gas6-Induced Inhibition of Epithelial-Mesenchymal Transition, Migration, and Invasion of Lung Alveolar Epithelial Cells.

Previously, we demonstrated that growth arrest-specific protein 6 (Gas6)/Axl or Mer signaling inhibited the transforming growth factor (TGF)-ß1-induced epithelial-mesenchymal transition (EMT) in lung epithelial cells. Hepatocyte growth factor (HGF) has also been shown to inhibit TGF-ß1-induced changes in EMT markers. Here, we examined whether Gas6 signaling can induce the production of HGF and c-Met in lung alveolar epithelial cells to mediate the inhibition of EMT and to inhibit the migration and invasion of epithelial cells. The inhibition of the RhoA/Rho kinase pathway, using either a RhoA-targeted small interfering RNA (siRNA) or the Rho kinase pharmacologic inhibitor Y27362, prevented the inhibition of TGF-ß1-induced EMT in LA-4 cells and primary alveolar type II (AT II) epithelial cells. The c-Met antagonist PHA-665752 also blocked the anti-EMT effects associated with Gas6. Moreover, treatment with Y27362 or PHA-665752 prevented the Gas6-mediated inhibition of TGF-ß1-induced migration and invasion. Our data provided evidence that the RhoA-dependent production of HGF and c-Met mediated the Gas6-induced inhibition of EMT, migration and invasion in lung alveolar epithelial cells. Thus, Gas6/Axl and Mer/RhoA signaling may be necessary for the maintenance of homeostasis in the alveolar epithelium, via HGF and c-Met.

A Community-Based Intervention for Improving Medication Adherence for Elderly Patients with Hypertension in Korea.

The chronic disease management program, a community-based intervention including patient education, recall and remind service, and reduction of out-of-pocket payment, was implemented in 2005 in Korea to improve patients' adherence for antihypertensive medications. This study aimed to assess the effect of a community-based hypertension intervention intended to enhance patient adherence to prescribed medications. This study applied a non-equivalent control group design using the Korean National Health Insurance Big Data. Hongcheon County has been continuously implementing the intervention program since 2012. This study involved a cohort of patients with hypertension aged >65 and <85 years, among residents who lived in the study area for five years (between 2010 and 2014). The final number of subjects was 2685 in both the intervention and control region. The indirect indicators were analyzed as patients' adherence and level of continuous treatment using the difference-in-difference regression. The proportion of hypertensive patients who continuously received insurance benefits for >240 days in 2014 was 81.0% in the intervention region and 79.7% in the control region. The number of dispensations per prescription and the dispensation days per hypertensive patient in the intervention region increased by approximately 10.88% and 2.2 days on average by month, respectively, compared to those in the control region. The intervention program encouraged elderly patients with hypertension to receive continuous care. Another research is needed to determine whether further improvement in the continuity of comprehensive care will prevent the progression of cardiovascular diseases.

Exogenous Hydrogen Peroxide Induces Lipid Raft-Mediated STAT-6 Activation in T Cells.

BACKGROUND/AIMS: CD4+ T cells are a critical component of the adaptive immune response. While the mechanisms controlling the differentiation of the Th1, Th17, and regulatory T cell subsets from naïve CD4+ T cells are well described, the factors that induce Th2 differentiation are still largely unknown. METHODS: The effects of treatment with exogenous H2O2 on STAT-6 phosphorylation and activation in T cells were examined by immunoblotting, immunofluorescence and gel shift assay. Anti-CD3 antibody and methyl-ß-cyclodextrin were utilized to induce lipid raft assembly and to investigate the involvement of lipid rafts, respectively. RESULTS: Jurkat and EL-4 T cells that were exposed to H2O2 showed rapid and strong STAT-6 phosphorylation, and the extent of STAT-6 phosphorylation was enhanced by co-treatment with anti-CD3 antibody. The effect of H2O2 on STAT-6 phosphorylation and translocation was inhibited by disruption of lipid rafts. STAT-6 activation in response to H2O2 treatment regulated IL-4 gene expression, and this response was strengthened by treatment with anti-CD3. CONCLUSION: Our results indicate that reactive oxygen species such as H2O2 can act on upstream and initiating factors for activation of STAT-6 in T cells and contribute to formation of a positive feedback loop between STAT-6 and IL-4 in the Th2 differentiation process.

Black cohosh inhibits 17ß-estradiol-induced cell proliferation of endometrial adenocarcinoma cells.

This study was conducted to investigate the effect of black cohosh (BC) extract on the proliferation and apoptosis of Ishikawa cells. Ishikawa human endometrial adenocarcinoma cells were treated with or without BC (1, 5, 10 and 25 µM) and cell proliferation and cytotoxicity were measured by CCK-8 assays and flow cytometry analysis. Additionally, Ishikawa cells were treated with 17ß-estradiol (E2), E2 + progesterone and E2 + BC (5 and 10 µM) and the effect of BC and progesterone on E2-induced cell proliferation was analyzed. BC decreased the proliferation of Ishikawa cells at a dose-dependent rate compared with the control group (p < 0.05). The proliferation of Ishikawa cells increased in the presence of E2, whereas the subsequent addition of progesterone or BC decreased proliferation to the level of the control group (p < 0.05). The inhibitory effect of BC on E2-induced cell proliferation was greater than the inhibitory effect of progesterone. In conclusion, BC induces apoptosis in Ishikawa cells and suppresses E2-induced cell proliferation in Ishikawa cells. BC could be considered a candidate co-treatment agent of estrogen-dependent tumors, especially those involving endometrial cells.

Hyaluronic acid induces COX-2 expression via CD44 in orbital fibroblasts from patients with thyroid-associated ophthalmopathy.

PURPOSE: The aim of this study was to determine the effect of hyaluronic acid (HA) on cyclooxygenase (COX)-2 expression in orbital fibroblasts from patients with thyroid-associated ophthalmopathy (TAO). METHODS: Primary cultured orbital fibroblasts were obtained from patients with TAO and non-TAO subjects. Dermal and conjunctival fibroblasts were cultured from the eyelid skin of subjects undergoing cosmetic lid surgery or cataract surgery, respectively. The cells were treated with HA and the transcriptional and translational levels of COX-2 were measured. The expression of CD44 on each type of cells was determined, and the involvement of CD44 in the HA-induced COX-2 increase in orbital fibroblasts from patients with TAO was evaluated by using CD44 knockdown cells and by pretreatment with neutralizing antibody. The relevance of the mitogen-activated protein kinase (MAPK) or nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-mediated signaling pathway was assessed by immunoblotting for the phosphorylated form of each MAPK or IκB and by using specific inhibitors to these pathways. RESULTS: Hyaluronic acid increased COX-2 expression in orbital fibroblasts from patients with TAO, which was not observed in the cells from non-TAO subjects and conjunctival or dermal fibroblasts. Orbital fibroblasts from patients with TAO expressed significantly higher level of CD44 than non-TAO cells, and the increased COX-2 expression by HA in these cells was attenuated by knockdown or neutralizing of CD44. Hyaluronic acid induced MAPK and IκB phosphorylation; and cotreatment with specific MAPK or NF-κB inhibitors halted HA-induced transcription of COX-2, suggesting the involvement of these signaling pathways. CONCLUSIONS: Hyaluronic acid induced COX-2 expression in orbital fibroblasts from patients with TAO via CD44 through the MAPK and NF-κB-mediated signaling pathways. These results suggest that HA may have a proinflammatory role in the pathogenesis of TAO by inducing COX-2.

SHP-2 binds to caveolin-1 and regulates Src activity via competitive inhibition of CSK in response to H2O2 in astrocytes.

Reactive oxygen species (ROS) regulate diverse cellular functions by triggering signal transduction events, such as Src and mitogen-activated protein (MAP) kinases. Here, we report the role of caveolin-1 and Src homology 2 domain-containing protein tyrosine phosphatase 2 (SHP-2) in H2O2-induced signaling pathway in brain astrocytes. H2O2-mediated oxidative stress induced phosphorylation of caveolin-1 and association between p-caveolin-1 and SHP-2. SHP-2 specifically bound to wild-type caveolin-1 similarly to c-Src tyrosine kinase (CSK), but not to phosphorylation-deficient mutant of caveolin-1 (Y14A), and interfered with complex formation between caveolin-1 and CSK. In the presence of CSK siRNA, binding between caveolin-1 and SHP-2 was enhanced by H2O2 treatment, which led to reduced Src phosphorylation at tyrosine (Tyr) 530 and enhanced Src phosphorylation at Tyr 419. In contrast, siRNA targeting of SHP-2 facilitated H2O2-mediated interaction between caveolin-1 and CSK and enhanced Src phosphorylation at Tyr 530, leading to subsequent decrease in Src downstream signaling, such as focal adhesion kinase (FAK) and extracellular signal-related kinase (ERK). Our results collectively indicate that SHP-2 alters Src kinase activity by interfering with the complex formation between CSK and phosphotyrosine caveolin-1 in the presence of H2O2, thus functions as a positive regulator in Src signaling under oxidative stress in brain astrocytes.

Loss of the promyelocytic leukemia protein in gastric cancer: implications for IP-10 expression and tumor-infiltrating lymphocytes.

Gastric cancer is one of the most common causes of cancer-related mortality worldwide. Expression of the tumor suppressor, promyelocytic leukemia (PML) protein, is reduced or abolished in gastric carcinomas, in association with an increased level of lymphatic invasion, development of higher pTNM staging, and unfavorable prognosis. Herein, we investigated the relationship between the extent of tumor-infiltrating lymphocytes and the status of PML protein expression in advanced gastric carcinoma. We observed higher numbers of infiltrating T-cells in gastric carcinoma tissues in which PML expression was reduced or abolished, compared to tissues positive for PML. The extent of T-cell migration toward culture supernatants obtained from interferon-gamma (IFN-γ-stimulated gastric carcinoma cell lines was additionally affected by expression of PML in vitro. Interferon-gamma-inducible protein 10 (IP-10/CXCL10) expression was increased in gastric carcinoma tissues displaying reduced PML levels. Moreover, both Pml knockout and knockdown cells displayed enhanced IP-10 mRNA and protein expression in the presence of IFN-γ. PML knockdown increased IFN-γ-mediated Signal Transducer and Activator of Transcription-1 (STAT-1) binding to the IP-10 promoter, resulting in elevated transcription of the IP-10 gene. Conversely, PML IV protein expression suppressed IP-10 promoter activation. Based on these results, we propose that loss of PML protein expression in gastric cancer cells contributes to increased IP-10 transcription via enhancement of STAT-1 activity, which, in turn, promotes lymphocyte trafficking within tumor regions.