Induction of insulin‐like growth factor‐I by interleukin‐17F in bronchial epithelial cells

Cite this as: M. Kawaguchi, J. Fujita, F. Kokubu, G. Ohara, S‐K Huang, S. Matsukura, Y. Ishii, M. Adachi, H. Satoh and N. Hizawa, Clinical & Experimental Allergy, 2010 (40) 1036–1043. Background Increased expression of IL‐17F has been noted in the airway of asthmatic patients, but its role in asthma has not been fully elucidated. Insulin‐like growth factor‐I (IGF‐I) is known to be involved in airway remodelling and inflammation, while its regulatory mechanisms remain to be defined. Objective To further clarify the biological function of IL‐17F, we investigated whether IL‐17F is able to regulate the expression of IGF‐I in bronchial epithelial cells. Methods Bronchial epithelial cells were stimulated with IL‐17F in the presence or absence of T‐helper type 2 cytokines. Various kinase inhibitors were added to the culture to identify the key signalling events leading to the expression of IGF‐I, in conjunction with the use of short interfering RNAs (siRNAs) targeting mitogen‐ and stress‐activated protein kinase (MSK) 1, p90 ribosomal S6 kinase (p90RSK), and cyclic AMP response element‐binding protein (CREB). Results IL‐17F significantly induced IGF‐I gene and protein expression, and co‐stimulation with IL‐4 and IL‐13 augmented its production. MAP kinase kinase (MEK) inhibitors and the Raf1 kinase inhibitor significantly inhibited IGF‐I production, and the combination of PD98059 and Raf1 kinase inhibitor showed further inhibition. Overexpression of Raf1 and Ras dominant‐negative mutants inhibited its expression. MSK1 inhibitors significantly blocked IL17F‐induced IGF‐I expression. Moreover, transfection of the siRNAs targeting MSK1, p90RSK, and CREB blocked its expression. Conclusions In bronchial epithelial cells, IL‐17F is able to induce the expression of IGF‐I via the Raf1–MEK1/2–ERK1/2–MSK1/p90RSK–CREB pathway in vitro.     

Insulin‐like growth factor‐1 receptor is associated with better prognosis in classical Hodgkin's lymphoma: Correlation with MET expression

The purpose of this study was to examine the prognostic significance of insulin‐like growth factor‐1 receptor (IGF‐1R) expression alone and in relation to the expression of the MET‐ receptor and the MET‐homologous receptor RON, in classical Hodgkin's lymphoma (cHL). Tumour samples from patients with cHL (n = 202; median age 37.5 years) were analysed retrospectively for IGF‐R1, MET or RON expression by immunohistochemistry using tissue microarrays. The median follow‐up time was 3.7 years (range, 0.1–20 years). Twenty‐nine patients (14.3%) expressed IGF‐1R protein in Hodgkin/Reed–Sternberg (HRS) cells, which was associated with a better overall survival (OS) (P = 0.036). IGF‐1R expression was closely associated with MET receptor expression and low level of lactate dehydrogenase. In patients with cHL receiving doxorubicin, bleomycin, vinblastine and dacarbazine, those expressing IGF‐1R showed a trend towards better OS and event‐free survival than IGF‐1R‐negative patients (P = 0.129 and P = 0.115 respectively), but statistical significance was not reached. This study suggests that IGF‐1R expression could be associated with better clinical outcome in cHL but is significantly associated with the expression of MET receptor.     

A 3D tri‐culture system reveals that activin receptor‐like kinase 5 and connective tissue growth factor drive human glomerulosclerosis

Glomerular scarring, known as glomerulosclerosis, occurs in many chronic kidney diseases and involves interaction between glomerular endothelial cells (GECs), podocytes, and mesangial cells (MCs), leading to signals that promote extracellular matrix deposition and endothelial cell dysfunction and loss. We describe a 3D tri‐culture system to model human glomerulosclerosis. In 3D monoculture, each cell type alters its phenotype in response to TGFβ, which has been implicated as an important mediator of glomerulosclerosis. GECs form a lumenized vascular network, which regresses in response to TGFβ. MCs respond to TGFβ by forming glomerulosclerotic‐like nodules with matrix deposition. TGFβ treatment of podocytes does not alter cell morphology but increases connective tissue growth factor (CTGF) expression. BMP7 prevents TGFβ‐induced GEC network regression, whereas TGFβ‐induced MC nodule formation is prevented by SMAD3 siRNA knockdown or ALK5 inhibitors but not BMP7, and increased phospho‐SMAD3 was observed in human glomerulosclerosis. In 3D tri‐culture, GECs, podocytes, and MCs form a vascular network in which GECs and podocytes interact intimately within a matrix containing MCs. TGFβ treatment induces formation of nodules, but combined inhibition of ALK5 and CTGF is required to prevent TGFβ‐induced nodule formation in tri‐cellular cultures. Identification of therapeutic targets for glomerulosclerosis depends on the 3D culture of all three glomerular cells. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Sustained low‐dose growth hormone therapy optimizes bioactive insulin‐like growth factor‐I level and may enhance CD4 T‐cell number in HIV infection

High‐dose recombinant human growth hormone (rhGH) (2–6 mg/day) regimes may facilitate T‐cell restoration in patients infected with human immunodeficiency virus (HIV) on highly active antiretroviral therapy (HAART). However, high‐dose rhGH regimens increase insulin‐like growth factor‐I (IGF‐I) to supra‐physiological levels associated with severe side effects. The present study investigated whether lower doses of rhGH may improve T‐cell restoration in patients infected with HIV following an expedient response of total and bioactive (i.e., free) IGF‐I. A previous 16‐week pilot‐study included six HIV‐infected patients on stable HAART to receive rhGH 0.7 mg/day, which increased total (+117%, P < 0.01) and free (+155%, P < 0.01) IGF‐I levels. The study was extended to examine whether continuous use of low‐dose rhGH (0.7 mg/day until week 60; 0.4 mg/day from week 60 to week 140) would maintain expedient IGF‐I levels and improve CD4 T‐cell response. Total and free IGF‐I increased at week 36 (+97%, P < 0.01 and +125%, P < 0.01, respectively) and week 60 (+77%, P = 0.01 and +125%, P < 0.01) compared to baseline levels (161 ± 15 and 0.75 ± 0.11 µg/L). CD4 T‐cell number increased at week 36 (+15%, P < 0.05) and week 60 (+31%, P = 0.01) compared to baseline levels (456 ± 55 cells/µL). Following rhGH dose reduction, total IGF‐I and CD4 T‐cell number remained increased at week 88 (+44%, P = 0.01 and +33%, P < 0.01) and week 140 (+46%, P = 0.07 and +36%, P = 0.02) compared to baseline levels. These data support the notion that low‐dose rhGH regimens may increase expediently total and bioactive IGF‐I and improve T‐cell restoration in patients infected with HIV on HAART. J. Med. Virol. 82:197–205, 2010. © 2009 Wiley‐Liss, Inc.     

Age‐ and site‐specific decline in insulin‐like growth factor‐I receptor expression is correlated with differential growth plate activity in the mouse hindlimb

The proximal and distal growth plates of the principal long bones do not contribute equally to longitudinal growth. Most forelimb elongation occurs at the shoulder and wrist, while most hindlimb growth occurs at the knee. This study examined whether insulin‐like growth factor‐I (IGF‐I), a potent growth regulator, could underlie this variation via differential receptor expression. The spatiotemporal distribution of the IGF‐I receptor (IGF‐IR) was mapped in hindlimb growth plates (overall and within regional zones) from immature mice using immunohistochemistry. Growth activity was assessed by size/morphology of the growth plate and proliferating cell nuclear antigen (PCNA) expression. Both IGF‐IR and PCNA staining declined considerably with age in the proximal femur and distal tibia (hip and ankle), but expression remained high in the more active distal femur and proximal tibia (knee) throughout growth. Growth plate size decreased with age in all sites, but the absolute and relative decline in IGF‐IR in the hips and ankles of older mice indicated a site‐specific loss of IGF‐I sensitivity in these less active regions. These results suggest that regulation of the IGF‐IR may at least partially mediate differential long bone growth, thereby providing a local mechanism for altering skeletal proportions absent modification of systemic hormone levels. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.     

Beta-catenin abnormalities and associated insulin-like growth factor overexpression are important in phyllodes tumours and fibroadenomas of the breast

The aim of this study was to assess the expression of IGF-I and IGF-II in phyllodes tumours and fibroadenomas and to see if there is any correlation between nuclear beta-catenin expression and IGF-I and IGF-II expression in these tumours. In a previous study, it has been shown that Wnt signalling is important in the pathogenesis of phyllodes tumours of the breast. Epithelial Wnt5a overexpression and stromal Wnt2 overexpression were associated with abnormal, nuclear localization of beta-catenin in the stromal cells of these tumours. However, not all tumours with beta-catenin accumulation showed Wnt overexpression. One other possible cause of beta-catenin accumulation is overexpression of insulin-like growth factors (IGFs), as both IGF-I and IGF-II have been shown to stabilize beta-catenin. In this study, 30 fibroadenomas of the breast were assessed for beta-catenin expression using immunohistochemistry and the results were compared with previous data from 119 phyllodes tumours. In situ hybridization was used to assess IGF-I and IGF-II expression in 23 phyllodes tumours and 16 fibroadenomas. Nineteen phyllodes tumours (83%) showed widespread overexpression of IGF-II and 5/23 (22%) showed widespread overexpression of IGF-I. IGF-I expression correlated with nuclear beta-catenin staining in phyllodes tumours. Malignant phyllodes tumours showed no or little IGF-I expression. There was a degree of nuclear beta-catenin expression in the stroma (weak in 33%, moderate in 27%, and strong in 40%) in all fibroadenomas and nuclear beta-catenin staining correlated with IGF-I overexpression. Extensive IGF-II overexpression was also found in the majority of fibroadenomas (12/16). These results support the hypothesis that IGF-I and IGF-II overexpression may be important in the pathogenesis of fibroepithelial neoplasms of the breast and that IGF-I overexpression is likely to be contributing to the nuclear beta-catenin localization observed in the tumours.     

Heparin co‐factor II enhances cell motility and promotes metastasis in non‐small cell lung cancer

Using the Serial Analysis of Gene Expression (SAGE) database from the Cancer Genome Anatomy Project, we identified heparin co‐factor II (HCII), which is over‐expressed in non‐small cell lung cancer (NSCLC). Here, we investigated the clinical significance of HCII and provided molecular evidence to support the suggestion that HCII could enhance cancer metastasis in NSCLC. We found that high HCII expression in tumour tissue was associated with increased cancer recurrence and shorter overall survival times in 75 clinically operable NSCLC patients. High pretreatment plasma concentration of HCII was associated with reduced overall survival in 57 consecutive NSCLC patients. We over‐expressed and knocked down HCII expression in lung cancer cell lines and confirmed that HCII could promote cell motility, invasion ability and filopodium dynamics in NSCLC cells in vitro and increased metastatic colonization in an in vivo mouse model. Exogenous treatment of HCII promoted cancer cell migration, and this promigratory effect of HCII was independent of thrombin. We further showed that HCII could up‐regulate cancer cell migration through the activation of PI3K, which acts upstream of Rac1 and Cdc42, and this effect could be blocked by heparin. We suggest that HCII is a novel metastasis enhancer and may be used as a prognostic predictor for heparin treatment in NSCLC. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd     

Practical utility of insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1, and epithelial membrane antigen for distinguishing malignant mesotheliomas from benign mesothelial proliferations

The differentiation of malignant mesotheliomas and benign mesothelial proliferations is crucial in determining patient care and prognosis. But, this distinction can be extremely difficult, particularly in small biopsies. Recently, insulin‐like growth factor II mRNA‐binding protein 3 (IMP3) and glucose transporter 1 (GLUT‐1) have been reported as specific and sensitive markers in the distinction of mesotheliomas from benign mesothelial proliferations. The purpose of this study is to evaluate the utility of IMP3, GLUT‐1, and epithelial membrane antigen (EMA) immunohistochemistry for distinguishing mesotheliomas from benign mesothelial proliferations. Immunoexpression of IMP3, GLUT‐1, and EMA was evaluated in 88 malignant mesotheliomas, 35 adenomatoid tumors, and 20 benign lung tissues with reactive mesothelial cells. The sensitivity for IMP3, GLUT‐1, and EMA was 37%, 21%, and 41%, respectively. The specificity for IMP3, GLUT‐1, and EMA was 100%. When IMP3, GLUT1, and EMA combined, the sensitivity was 66% for IMP3/EMA staining, 53% for GLUT‐1/EMA staining, and 45% for IMP3/GLUT‐1. Use of IMP3 and EMA together is more helpful to distinguish malignant mesotheliomas from benign mesothelial proliferations than the use of IMP3 or EMA alone.     

Notch1 is an important mediator for enhancing of B‐cell activation and antibody secretion by Notch ligand

The roles of Notch1 and Notch2 in T‐cell function have been well studied, but the functional roles of Notch in B cells have not been extensively investigated, except for Notch2 involvement in peripheral marginal zone B‐cell differentiation. This study examined the roles of Notch1 in murine primary B cells. During B‐cell activation by B‐cell receptor ligation, Notch1 was up‐regulated while Notch2 was not. In addition, Notch1 up‐regulation itself did not contribute to the further activation of B cells, but the Notch ligand was important for Notch1‐mediated further B‐cell activation. Moreover, Notch1 deficiency significantly decreased B‐cell activation and antibody secretion under the presence of Notch ligand. These data suggest that Notch1 is an important mediator for enhancing B‐cell activation and antibody secretion by Notch ligand.     

Insulin‐like growth factor binding protein‐2 as a novel biomarker for disease activity and renal pathology changes in lupus nephritis

Lupus nephritis (LN) is one of the most serious manifestations of systemic lupus erythematosus. Invasive renal biopsy remains the gold standard for the diagnosis and management of LN. The objective of this study is to validate serum insulin‐like growth factor binding protein‐2 (IGFBP‐2) as a novel biomarker for clinical disease and renal pathology in LN. Eighty‐five biopsy‐proven lupus nephritis patients, 18 chronic kidney disease (CKD) patients and 20 healthy controls were recruited for enzyme‐linked immunosorbent assay (ELISA) testing of serum IGFBP‐2 levels. Compared to CKD patients of origins other than lupus or healthy controls, serum IGFBP‐2 levels were elevated significantly in LN patients. Serum IGFBP‐2 was able to discriminate LN patients from the other two groups of patients [area under the curve (AUC) = 0·65, 95% confidence interval (CI) = 0·52–0·78; P = 0·043 for LN versus CKD; 0·97, 95% CI = 0·93–1·00; P < 0·0001 for LN versus healthy controls]. Serum IGFBP‐2 was a potential indicator of both global disease activity and renal disease activity in LN patients, correlated with serum creatinine levels (r = 0·658, P < 0·001, n = 85) and urine protein‐to‐creatinine levels (r = 0·397, P < 0·001, n = 85). More importantly, in 19 concurrent patient samples, serum IGFBP‐2 correlated with the chronicity index of renal pathology (r = 0·576, P = 0·01, n = 19) but not renal pathological classification. In conclusion, serum IGFBP‐2 is a promising biomarker for lupus nephritis, reflective of disease activity and chronicity changes in renal pathology.     

Expression of 14‐3‐3 sigma and eta proteins is unrelated to survival in metastatic high‐grade serous carcinoma

The objective of this study was to analyze the expression and clinical role of 14‐3‐3 family proteins in high‐grade serous carcinoma (HGSC). Protein expression of 14‐3‐3 sigma (14‐3‐3σ) and 14‐3‐3 eta (14‐3‐3η) by immunohistochemistry was studied in 298 HGSC specimens (249 peritoneal, 49 pleural) and was analyzed for association with clinicopathologic parameters, chemoresponse and survival. The 14‐3‐3σ protein was diffusely (>75% of cells) expressed in 100% of carcinomas in analysis of a pilot series and was therefore not further analyzed. The 14‐3‐3η protein was expressed to a variable extent in 260/298 (87%) effusions. Higher 14‐3‐3η protein expression was significantly related to higher CA 125 levels at diagnosis (p = 0.004), but was unrelated to other clinicopathologic parameters, chemoresponse or survival. Analysis of the association between 14‐3‐3η and previously studied proteins regulating mitosis showed positive association with class III β‐tubulin expression (p = 0.025). The present study documents frequent expression of 14‐3‐3σ and 14‐3‐3η in HGSC effusions, but does not support a role for these proteins as prognostic markers or predictors of chemotherapy response in metastatic HGSC.     

Cystein‐serine‐rich nuclear protein 1, Axud1/Csrnp1, is essential for cephalic neural progenitor proliferation and survival in zebrafish

The CSRNP (cystein‐serine‐rich nuclear protein) family has been conserved from Drosophila to human. Although knockout mice for each of the mammalian proteins have been generated, their function during vertebrate development has remained elusive. As an alternative to obtain insights on CSRNP's role in development, we have analysed the expression pattern and function of one member of this family, axud1, during zebrafish development. Our expression analysis indicates that axud1 is expressed from cleavage to larval stages in a dynamic pattern, becoming restricted after gastrulation to anterior regions of the developing neuraxis and later on concentrated predominantly in proliferating domains of the brain. Knockdown analysis using antisense morpholinos shows that reducing Axud1 levels impairs neural progenitor cell proliferation and survival, revealing an essential function of this gene for the growth of cephalic derivatives. The brain growth phenotypes elicited by decreasing Axud1 expression are specific and independent of anterior‐posterior patterning events, initial establishment of neural progenitors, or neural differentiation occurring in this tissue. However, Axud1 is necessary for six3.1 expression and is positively regulated by sonic hedgehog. Phylogenetic examination shows that axud1 is likely to be the ortholog of the only member of this family present in Drosophila, as well as to the previously described mouse CSRNP1 and to human AXUD1 (Axin upregulated‐1). Thus, we provide evidence as to the role of axud1 in brain growth in vertebrates. Developmental Dynamics, 2009. © 2009 Wiley‐Liss, Inc.