Genomic ablation of hepatocyte-specific fibroblast growth factor receptor (FGFR)4 in mice revealed a role of FGF signaling in cholesterol and bile acid metabolism and hepatolobular restoration in response to injury without effect on liver development or hepatocyte proliferation. Although the potential role of all 23 FGF polypeptides in the liver is still unclear, the most widely studied prototypes, FGF1 and FGF2, are present and have been implicated in liver cell growth and function in vitro. To determine whether FGF1 and FGF2 play a role in response to injury and fibrosis, we examined the impact of both acute and chronic exposure to carbon tetrachloride (CCl 4 ) in the livers of FGF1-and FGF2-deficient mice. After acute CCl 4 exposure, FGF1(؊/؊)FGF2(؊/؊) mice exhibited an accelerated release of serum alanine aminotransferase similar to FGFR4 deficiency, but no effect on overall hepatolobular restoration or bile acid metabolism. The fibroblast growth factors (FGFs) comprise a family of 23 reported members that have varying affinities for variants of four different FGF receptor kinases (FGFR1 to FGFR4). 1-3 FGF1 and FGF2, the first two cloned members of the FGF family, 4,5 have received the most study, are widely expressed, and thus, predicted to be involved in tissue-specific functions and associated pathologies at their site of expression. 6,7 In vitro FGF1 affects cells of multiple origin whereas activity of FGF2 appears more limited to cells derived from mesenchyme and neuroectoderm. 8 FGF1 and FGF2 have been implicated in derivation of the liver from foregut endoderm. 9 However, mice lacking FGF1, FGF2, or both FGF1 and FGF2 are viable, fertile, and grossly indistinguishable from wild type (WT) except for modest defects in cardiovascular tissue, healing of skin wounds, and neuronal tissue. 3,10,11 This suggests that FGF1 and FGF2 alone are not essential for embryonic development or are compensated by other members of the extensive FGF ligand family. Consequently, FGF1-and FGF2-deficient animals are available for study of the role of the two factors in adult tissue homeostasis. Despite their ubiquity, little has emerged except for the modest effects of ablation of FGF1 and FGF2 in the cardiovascular, skin, and nervous systems.Although the levels of mRNA transcripts are low, longlived FGF1 and FGF2 polypeptides are present in the resting liver at significant levels. 12 This suggests that a significant reservoir of both ligands is present in the resting liver in an inactive state before activation and
Our previous microarray data showed that microRNA-224 (miR-224) was downregulated in human prostate cancer (PCa) tissues compared with adjacent benign tissues. However, the underlying mechanisms by which miR-224 is involved in PCa remain unclear. In this study, we identified TRIB1 as a target gene of miR-224. Forced expression of miR-224 suppressed PCa cell proliferation, invasion and migration, and promoted cell apoptosis by downregulating TRIB1. Moreover, the expression level of miR-224 in PCa tissues was negatively correlated with that of TRIB1. miR-224 downregulation was frequently found in PCa tissues with metastasis, higher PSA level and clinical stage, whereas TRIB1 upregulation was significantly associated with metastasis. Both miR-224 downregulation and TRIB1 upregulation were significantly associated with poor biochemical recurrence-free survival of patients with PCa. In conclusion, these findings reveal that the aberrant expression of miR-224 and TRIB1 may promote PCa progression and have potentials to serve as novel biomarkers for PCa prognosis.
Carbon tetrachloride (CCl 4 ) intoxification in rodents is a commonly used model of both acute and chronic liver injury. Recently, we showed that mice in which FGFR4 was ablated from the germline exhibited elevated cholesterol metabolism and bile acid synthesis coincident with unrepressed levels of cytochrome P450 7A (CYP7A), the rate-limiting enzyme in cholesterol disposal. Of the four fibroblast growth factor (FGF) receptor genes expressed in adult liver, FGFR4 is expressed specifically in mature hepatocytes. To determine whether FGFR4 plays a broader role in liver-specific metabolic functions, we examined the impact of both acute and chronic exposure to CCl 4 in FGFR4-deficient mice. Following acute CCl 4 exposure, the FGFR4-deficient mice exhibited accelerated liver injury, a significant increase in liver mass and delayed hepatolobular repair. Chronic CCl 4 exposure resulted in severe fibrosis in livers of FGFR4-deficient mice compared to normal mice. Analysis at both mRNA and protein levels indicated an 8-hour delay in FGFR4-deficient mice in the down-regulation of cytochrome P450 2E1 (CYP2E1) protein, the major enzyme whose products underlie CCl 4 -induced injury. These results show that hepatocyte FGFR4 protects against acute and chronic insult to the liver and prevents accompanying fibrosis. The results show that FGFR4 acts by promotion of processes that restore hepatolobular architecture rather than cellularity while limiting damage due to prolonged CYP2E1 activity. (Am J Pathol
BackgroundAccumulating epidemiological evidence shows that life event stressors are major vulnerability factors for psychiatric diseases such as major depression. It is also well known that social isolation in male mice results in aggressive behavior. However, it is not known how social isolation-induced aggression affects anxiety and depressive-like behavior in isolated male mice subjected to unpredictable chronic mild stress (CMS), an animal model of depression.Methodology/Principal FindingsC57/B6 male mice were divided into 3 groups; non-stressed controls, in Group I; isolated mice subjected to the CMS protocol in Group II and aggression by physical contact in socially isolated mice subjected to the CMS protocol in Group III. In the sucrose intake test, ingestion of a 1% sucrose solution by mice in Groups II and III was significantly lower than in Group I. Furthermore, intake of this solution in Group III mice was significantly lower than in Group II mice. In the open field test, mice in Group III, showed reduced locomotor activity and reduced entry and retention time in the central zone, compared to Groups I and II mice. Moreover, the distances moved in 1 hour by Group III mice did not differ between night and morning. In the light/black box test, Groups II and III animals spent significantly less time in the light box compared to Group I animals. In the tail suspension test (TST) and forced swimming test (FST), the immobility times of Group II and Group III mice were significantly longer than in Group I mice. In addition, immobility times in the FST were significantly longer in Group III than in Group II mice.Conclusions/SignificanceThese findings show that social isolation-induced aggression could potentiate anxiety and depressive -like behaviors in isolated male mice subjected to CMS.
Parkinson's disease (PD) is the second most common neurodegenerative disease and is known to involve circadian dysfunction and oxidative stress. Although antioxidative defense is regulated by the molecular circadian clock, few studies have examined their function in PD and their regulation by silent information regulator 1 (SIRT1). We hypothesize that reduced antioxidative activity in models of PD results from dysfunction of the molecular circadian clock via the SIRT1 pathway. We treated rats and SH-SY5Y cells with 6-hydroxydopamine (6-OHDA) and measured the expression of core circadian clock and associated nuclear receptor genes using real-time quantitative PCR as well as levels of SIRT1, brain and muscle Arnt-like protein 1 (BMAL1), and acetylated BMAL1 using Western blotting. We found that 6-OHDA treatment altered the expression patterns of clock and antioxidative molecules in vivo and in vitro. We also detected an increased ratio of acetylated BMAL1:BMAL1 and a decreased level of SIRT1. Furthermore, resveratrol, an activator of SIRT1, decreased the acetylation of BMAL1 and inhibited its binding with CRY1, thereby reversing the impaired antioxidative activity induced by 6-OHDA. These results suggest that a dysfunctional circadian clock contributes to an abnormal antioxidative response in PD via a SIRT1-dependent BMAL1 pathway.
Background/Aims: Golgi phosphoprotein 3 (GOLPH3) is a newly reported oncogene that plays a significant role in regulating cell growth. Recent research has shown that overexpression of GOLPH3 is correlated with patient survival and M classification in breast cancer and other cancers. However, the mechanisms by which GOLPH3 contributes to metastasis in non-small cell lung cancer (NSCLC) have not been previously clarified and are therefore the focus of this work. Methods: Immunohistochemistry (IHC) and western blotting analysis were performed to assess the GOLPH3 protein level, small interfering RNA (siRNA) and transwell assays were conducted to investigate the role of GOLPH3 in migration and invasion, and real-time PCR was performed to estimate the level of GOLPH3 mRNA expression. Results: GOLPH3 was significantly correlated with clinicopathological variables, such as the clinical stage (P=0.012), T classification (P=0.002) and metastasis (M classification) (P=0.008), in NSCLC patients and was negatively correlated with the prognosis. Knockdown of GOLPH3 significantly suppressed the migratory and invasive ability of NSCLC cell lines and downregulated the enzyme activity and protein levels of MMP-2 and MMP-9. Conclusions: The expression level of GOLPH3 is correlated with metastasis and prognosis in NSCLC, and GOLPH3 mediates metastasis by regulating the protein levels of MMP-2 and MMP-9 in vitro.
BackgroundDysregulation of hedgehog pathway is observed in numerous cancers. Relevance of hedgehog pathway genes in cancer cohort and inhibition of its downstream effector (GLI1) towards metastasis in cell lines are explored in the study.MethodOne hundred fifty fresh tumours of breast cancer patients were collected for the study. Based on differential expression, panel of 6 key regulators of the pathway (SHH, DHH, IHH, PTCH1, SMO and GLI1) in microarray datasets were identified. Expressional profiles of aforementioned genes were later correlated with clinico-pathological parameters in Pakistani breast cancer cohort at transcript and protein levels. In addition, GLI1 over expressing breast cancer cell lines (MDA-MB-231 and MCF-7) were treated with GANT61 to explore its probable effects on metastasis.ResultSHH, DHH, PTCH1 and GLI1 were significantly over-expressed in tumours as compared with respective normal mammary tissues. A significant correlation of SHH, DHH and GLI1 expression with advanced tumour size, stages, grades, nodal involvement and distant metastasis was observed (p < 0.05). Over-expression of SHH, DHH and GLI1 was significantly related with patients having early onset and pre-menopausal status. Of note, hedgehog pathway was frequently up regulated in luminal B and triple negative breast cancer affected women. In addition, positive correlations were observed among aforementioned members of pathway and Ki67 (r-value: 0.63–0.78) emphasizing their role towards disease progression. Exposure of GANT61 (inhibitor for GLI1) significantly restricted cell proliferation, reduced cell motility and invasion.ConclusionRole of activated hedgehog pathway in breast cancer metastasis provides a novel target for cancer therapy against aggressive cancer subtypes.Electronic supplementary materialThe online version of this article (10.1186/s12964-017-0213-y) contains supplementary material, which is available to authorized users.
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