Association of sterol regulatory element binding protein 2 and insulin-like growth factor binding protein 3 genetic polymorphisms with avascular necrosis of the femoral head in the Chinese population

Background Sterol regulatory element binding protein （SREBP）-2 plays a key role in lipid homeostasis by stimulating gene expression of cholesterol biosynthetic pathways. The insulin-like growth factor binding protein （IGFBP） family regulates growth and metabolism, especially bone cell metabolism, and correlates with osteonecrosis. However, association of their gene polymorphisms with risk of avascular necrosis of the femoral head （ANFH） has rarely been reported. We determined whether SREBP-2 and IGFBP-3 gene polymorphisms were associated with increased ANFH risk in the Chinese population. Methods Two single nucleotide polymorphisms of SREBP2 gene, rs2267439 and rs2267443, and one of IGFBP-3 gene, rs2453839, were selected and genotyped in 49 ANFH patients and 42 control individuals by direct sequencing assay. Results The frequencies of rs2267439 TT and rs2267443 GA of SREBP2 and rs2453839 TT and CT of IGFBP-3 in the ANFH group showed increased and decreased tendencies （against normal control group）, respectively. Interaction analysis of genes revealed that the frequency of carrying rs2267439 TT and rs2267443 GA genotypes of SREBF-2 in ANFH patients was significantly higher than in the control group （P 〈0.05）. Association analysis between polymorphisms and clinical phenotype demonstrated that the disease course in ANFH patients with the rs2453839 TT genotype of IGFBP-3 was significantly shorter than that of CT＋CC carriers （P 〈0.01）. CT＋CC genotype frequency in patients with stage Ill/IV bilateral hip lesions was significantly higher than in those with stage Ill/IV unilateral lesions and stage II/111 bilateral lesions （P 〈0.05-0.02）. Conclusions Our results suggested that interaction of SREBP-2 gene polymorphisms and the relationship between the polymorphisms and clinical phenotype of IGFBP-3 were closely related to increased ANFH risk in the Chinese population. The most significant finding was that the CT＋CC genotype carriers of IGFBP-3 rs2453839 were highly associated with the development of ANFH.

Interplay between micro RNA-17-5p, insulin-like growth factor-Ⅱ through binding protein-3 in hepatocellular carcinoma

AIM: To investigate the effect of microR NA on insulinlike growth factor binding protein-3(IGFBP-3) and hence on insulin-like growth factor-Ⅱ(IGF-Ⅱ) bioavailability in hepatocellular carcinoma(HCC).METHODS: Bioinformatic analysis was performed using microrna.org, DIANA lab and Segal lab softwares. Total RNA was extracted from 23 HCC and 10 healthy liver tissues using mir Vana mi RNA Isolation Kit. microR NA-17-5p(miR-17-5p) expression was mimicked and antagonized in Hu H-7 cell lines using Hi Per Fect Transfection Reagent, then total RNA was extracted using Biozol reagent then reverse transcribed into cD NA followed by quantification of mi R-17-5p and IGFBP-3 expression using Taq Man real-time quantitative PCR. Luciferase reporter assay was performed to validate the binding of miR-17-5p to the 3'UTR of IGFBP-3. Free IGF-Ⅱ protein was measured in transfected Hu H-7 cells using IGF-Ⅱ ELISA kit. RESULTS: Bioinformatic analysis revealed IGFBP-3 as a potential target for miR-17-5p. Screening of miR-17-5p and IGFBP-3 revealed a moderate negative correlation in HCC patients, where mi R-17-5p was extensively underexpressed in HCC tissues(P = 0.0012), while IGFBP-3 showed significant upregulation in the same set of patients(P = 0.0041) compared to healthy donors. Forcing mi R-17-5p expression in Hu H-7 cell lines showed a significant downregulation of IGFBP-3 mR NA expression(P = 0.0267) and a significant increase in free IGF-Ⅱ protein(P = 0.0339) compared to mock untransfected cells using unpaired t-test. Luciferase assay validated IGFBP-3 as a direct target of mi R-17-5p; luciferase activity was inhibited by 27.5% in cells co-transfected with miR-17-5p mimics and the construct harboring the wild-type binding region 2 of IGFBP-3 compared to cells transfected with this construct alone(P = 0.0474).CONCLUSION: These data suggest that regulating IGF-Ⅱ bioavailability and hence HCC progression can be achieved through targeting IGFBP-3 via manipulating the expression of miR NAs.

Circulating insulin-like growth factor-binding protein 3 as prognostic biomarker in liver cirrhosis

AIM: To investigate the prognostic significance of insulin-like growth factor-binding protein 3(IGFBP-3) in patients with cirrhosis.METHODS: Prospective study that included two cohorts: outpatients with stable cirrhosis(n = 138) and patients hospitalized for acute decompensation(n = 189). Development of complications, mortality or liver transplantation was assessed by periodical phone calls and during outpatient visits. The cohort of stable cirrhosis also underwent clinical and laboratory evaluation yearly(2013 and 2014) in predefined study visits. In patients with stable cirrhosis, IGFBP-3 levels were measured at baseline(2012) and at second re-evaluation(2014). In hospitalized subjects, IGFBP-3 levels were measured in serum samples collected in the first and in the third day after admission and stored at-80 ℃. IGFBP-3 levels were measured by immunochemiluminescence.RESULTS: IGFBP-3 levels were lower in hospitalized patients as compared to outpatients(0.94 mcg/mL vs 1.69 mcg/m L, P < 0.001) and increased after liver transplantation(3.81 mcg/m L vs 1.33 mcg/mL, P = 0.008). During the follow-up of the stable cohort, 17 patients died and 11 received liver transplantation. Bivariate analysis showed that death or transplant was associated with lower IGFBP-3 levels(1.44 mcg/mL vs 1.74 mcg/m L, P = 0.027). The Kaplan-Meier transplant-free survival probability was 88.6% in patients with IGFBP-3 ≥ 1.67 mcg/mL and 72.1% for those with IGFBP3 < 1.67 mcg/mL(P = 0.015). In the hospitalized cohort, 30-d mortality was 24.3% and was independently associated with creatinine, INR, SpO_2/FiO_2 ratio and IGFBP-3 levels in the logistic regression. The 90-d transplant-free survival probability was 80.4% in patients with IGFBP-3 ≥ 0.86 mcg/mL and 56.1% for those with IGFBP3 < 0.86 mcg/mL(P < 0.001). CONCLUSION: Lower IGFBP-3 levels were associated with worse outcomes in patients with cirrhosis, and might represent a promising prognostic tool that can be incorporated in clinical practice.

Insulin-like growth factor-1, IGF binding protein-3, and the risk of esophageal cancer in a nested case-control study

AIM To assess the relationship between serum levels of insulin-like growth factor-1(IGF1)/IGF-binding protein-3(IGFBP3)and the risk of esophageal carcinoma.METHODS We assessed the relationship between the serum levels of these molecules and the risk of esophageal cancer in a prospective,nested case-control study of participants from the Japan Collaborative Cohort Study.A baseline survey was conducted from 1988 to 1990.Of the 110585 enrolled participants,35%donated blood samples.Those who had been diagnosed with esophageal cancer were considered cases for nested case-control studies.A conditional logistic model was used to estimate odds ratios for the incidence of esophageal cancer associated with serum IGF1 and IGFBP3 levels.RESULTS Thirty-one cases and 86 controls were eligible for the present assessment.The molar ratio of IGF1/IGFBP3,which represents the free and active form of IGF1,was not correlated with the risk of esophageal carcinoma.A higher molar difference between IGFBP3and IGF1,which estimates the free form of IGFBP3,was associated with a decreased risk of esophageal carcinoma(P=0.0146),and people in the highest tertile had the lowest risk(OR=0.107,95%CI:0.017-0.669).After adjustment for body mass index,tobacco use,and alcohol intake,the molar difference of IGFBP3-IGF1 was inversely correlated with the risk of esophageal carcinoma(P=0.0150).CONCLUSION The free form of IGFBP3,which is estimated by this molar difference,may be inversely associated with esophageal cancer incidence.

Serum measurements of testosterone, insulin-like growth factor 1, and insulin-like growth factor binding protein-3 in the diagnosis of prostate cancer among Korean men

瞄准：为了调查浆液的关系，睾丸激素，像胰岛素的生长因素(IGF )-1 和 IGF 有约束力的蛋白质(IGFBP )-3 在收到了激进的制动火箭的朝鲜的人与前列腺癌症的已知的预示的参数与前列腺癌症风险并且也铺平为临床上局部性的前列腺癌症的阴毛的前列腺切除术(RRP ) 。方法：全部的睾丸激素，免费睾丸激素， IGF-1 和 IGFBP-3 的浆液层次在随后收到了前列腺活体检视的 592 个病人被决定。结果在最后为前列腺癌症收到了 RRP 的病人之间被比较(n= 159 ) 并且没从活体检视与前列腺癌症被诊断的那些(控制组， n= 433 ) 。在前列腺癌症之中仅仅病人，神经质的层次获得了的浆液在与特定的抗原(PSA ) ，病理学的 T 阶段和病理学的格利森获得的浆液前列腺的关系被分析。结果：前列腺癌症病人和控制组没越过不同年龄组关于全部的睾丸激素，免费睾丸激素， IGF-1 和 IGFBP-3 的浆液层次表明重要差别。在癌症之中仅仅病人，没有重要协会与病理学的 T 舞台，病理学的格利森分数和外科手术前的 PSA 为全部的睾丸激素，免费睾丸激素， IGF-1 和 IGFBP-3 层次的浆液层次被观察。结论：我们的数据显示与 IGFBP-3 层次一起的浆液睾丸激素和 IGF-1 的简单数量化离子可能不在朝鲜的人在临床上局部性的前列腺癌症的诊断提供有用临床的信息。另外，我们的结果建议睾丸激素， IGF-1 和 IGFBP-3 的浆液层次可能显著地没在朝鲜的人与临床上局部性的前列腺癌症的已知的预示的因素被联系。

Increased expression of insulin-like growth factor-binding protein-3 is implicated in erectile dysfunction in two-kidney one-clip hypertensive rats after propranolol treatment

This study aimed to investigate the role of insulin-like growth factor-binding protein-3 （IGFBP-3） in erectUe dysfunction （ED） in two-kidney one-clip （2K-1C） hypertensive rats treated with the β-blocking agent propranolol. Adult male Wistar rats were randomly divided into three groups： a normal control group, a hypertensive control group and a propranolol treatment group （n=9）. After 4 weeks of propranolol treatment, intracavemous pressure （ICP） responses to electrical stimulation of the cavernous nerves were evaluated. The expression of IGFBP-3 and insulin-like growth factor-1 （IGF-1） mRNA and protein in the rat cavernous tissue were detected by quantitative real-time PCR and Western blot, respectively. The concentration of cyclic guanosine monophosphate （cGMP） in the cavernous tissue was determined by enzyme-linked immunosorbent assay （ELISA）. Cavernosal pressure in response to cavernous nerve stimulation was decreased 4 weeks after propranolol treatment （P〈0.01, compared to the hypertensive control group）. IGFBP-3 mRNA and protein expression was increased in the propranolol treatment group compared to the hypertensive control group （P〈O.01）, whereas IGF-1 expression was decreased in the propranolol treatment group compared to the hypertensive control group （P〈0.01）. In addition, cavernous cGMP concentration was decreased in the prepranolol treatment group compared to the hypertensive control group （P〈0.01）. Taken together, these results suggest that the upregulation of IGFBP-3 may play a role in the development of ED in hypertensive rats.

Changes of insulin-like growth factor-Ⅱ and insulin-like growth factor binding protein-3 in cerebrospinal fluid of children with tuberculous meningitis

BACKGROUND： Recent studies have found that insulin-like growth factors （IGFs） and insulin-like growth factor binding protein-3 （IGFBP-3） have stronger neurotrophic and neuroprotective effects. But whether their levels in cerebrospinal fluid could be used as an auxiliary indicator in differentially diagnosing tuberculous meningitis and viral encephalitis is not yet clear. OBJECTIVE： To explore the changes of insulin-like growth factor-Ⅱ （IGF-Ⅱ ） and IGFBP-3 in cerebrospinal fluid （CSF） of children with tuberculous meningitis and the significance of the changes. DESIGN： A non-randomized concurrent controlled study. SETTING： Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College. PARTICIPANTS： Thirty children with tuberculous meningitis （14 males and 16 females） were selected from the Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College from January 2005 to December 2006. Tuberculous meningitis was diagnosed according to their clinical manifestations, the history of close contact with tuberculosis, typical cerebrospinal fluid changes of tuberculous meningitis, positive tuberculosis antibody and effective antituberculosis treatment. There were 30 children （13 males and 17 females） with viral encephalitis, and viral encephalitis was diagnosed according to epidemiological history, clinical manifestations, conventional and biochemical changes of cerebrospinal fluid, and negative bacteriology judgment. Meanwhile, 30 children （13 males and 17 females） without infectious and central nervous system disease were selected as the control group. Informed consent was obtained from the parents of all the enrolled children. METHODS： ①The lumbar puncture operation was implemented immediately to obtain cerebrospinal fluid （3 mL）. The contents of IGF-Ⅱ and IGFBP-3 were detected with immunoradiometric assay. The concentrations of glucose and protein in cerebrospinal fluid were determined with a dry-chemical method. The number of white blood cells was counted by Fushi Method. ②The Pearson correlation analysis was used to analyze the correlation of the contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid with the leucocyte counting and the concentrations of glucose and protein in cerebrospinal fluid. MAIN OUTCOME MEASURES： The contents of IGF- Ⅱ and IGFBP-3 in cerebrospinal fluid, and their correlation with the leucocyte counting and the concentrations of glucose and protein in cerebrospinal fluid. RESULTS： ①Contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid： The contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid in the tuberculous meningitis group were significantly higher than those in the encephalitis virus group and control group （P 〈 0.05）. There was no significant difference in the contents of IGF- Ⅱ and IGFBP-3 in cerebrospinal fluid between the viral encephalitis group and control group （P 〉 0.05）. ②Correlation： The IGF- Ⅱ and IGFBP-3 contents in cerebrospinal fluid were positively correlated with the protein concentration in cerebrospinal fluid （r =0.821, 0.855, P 〈 0.01）, but negatively with the glucose （r =0.742, - 0.605, P 〈 0.01）. CONCLUSION- ①IGFs and IGVBPs are involved in the pathophysiological process of tuberculous meningitis, as well as the glucose and protein metabolism in cerebrospinal fluid. ②The IGF-Ⅱ and IGFBP-3 contents in cerebrospinal fluid can be used as the auxiliary indicators to differentially diagnose tuberculous meningitis and viral enceohalitis.

Insulin-like growth factor-binding protein-3 inhibits IGF-1-induced proliferation of human hepatocellular carcinoma cells

OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like growth factor-binding protein-3(IGFBP-3)suppresses HCC cell proliferation in both IGF-dependent and independent manners.The present study is to investigate whether treatment with exogenous IGFBP-3 inhibits bF GF and PDGF production and the cell proliferation of HCC cells.METHODS Cell Counting Kit 8 assay were designed to detect HCC cell proliferation,transcription factor early growth response-1(EGR1)involving in IGFBP-3 regulation of b FGF and PDGF were detected by RT-PCR and Western blot assays.Western blot assay was adopted to detect the IGFBP-3 regulating insulin-like growth factor 1 receptor(IGF-1R)signaling pathway.RESULTS The present study demonstrates that IGFBP-3 suppressed IGF-1-induced b FGF and PDGF expression while it does not affect their expression in the absence of IGF-1.To delineate the underlying mechanism,Western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1(EGR1)is involved in IGFBP-3 regulation of b FGF and PDGF.IGFBP-3 inhibition of type 1 insulin-like growth factor receptor(IGF1R),ERK and AKT activation is IGF-1-dependent.Furthermore,transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1,b FGF and PDGF expression.CONCLUSION In conclusion,these findings suggest that IGFBP-3suppresses transcription of EGR1 and its target genes b FGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation.It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation,suggesting that IGFBP-3 could be a target for the treatment of HCC.

Insulin-like growth factor binding protein related protein 1 knockdown attenuates hepatic ?brosis via the regulation of MMPs/TIMPs in mice

Background: Previous research suggested that insulin-like growth factor binding protein related protein 1(IGFBPrP1), as a novel mediator, contributes to hepatic fibrogenesis. Matrix metalloproteinases(MMP) and tissue inhibitors of metalloproteinases(TIMP) play an essential role in hepatic fibrogenesis by regulating homeostasis and remodeling of the extracellular matrix(ECM). However, the interaction between IGFBPrP1 and MMP/TIMP is not clear. The present study was to knockdown IGFBPrP1 to investigate the correlation between IGFBPrP1 and MMP/TIMP in hepatic fibrosis. Methods: Hepatic fibrosis was induced by thioacetamide(TAA) in mice. Knockdown of IGFBPrP1 expression by ultrasound-targeted microbubble destruction-mediated CMB-shRNA-IGFBPrP1 delivery, or inhibition of the Hedgehog(Hh) pathway by cyclopamine treatment, was performed in TAA-induced liver fibrosis mice. Hepatic fibrosis was determined by hematoxylin and eosin and Sirius red staining. Hepatic expression of IGFBPrP1, α-smooth muscle actin( α-SMA), transforming growth factor β 1(TGF β1), collagen I, MMPs/TIMPs, Sonic Hedgehog(Shh), and glioblastoma family transcription factors(Gli1) were investigated by immunohistochemical staining and Western blotting analysis. Results: We found that hepatic expression of IGFBPrP1, TGF β1, α-SMA, and collagen I were increased longitudinally in mice with TAA-induced hepatic fibrosis, concomitant with MMP2/TIMP2 and MMP9/TIMP1 imbalance and Hh pathway activation. Knockdown of IGFBPrP1 expression, or inhibition of the Hh pathway, reduced the hepatic expression of IGFBPrP1, TGF β1, α-SMA, and collagen I and re-established MMP2/TIMP2 and MMP9/TIMP1 balance. Conclusions: Our findings suggest that IGFBPrP1 knockdown attenuates liver fibrosis by re-establishing MMP2/TIMP2 and MMP9/TIMP1 balance, concomitant with the inhibition of hepatic stellate cell activation, down-regulation of TGF β1 expression, and degradation of the ECM. Furthermore, the Hh pathway mediates IGFBPrP1 knockdown-induced attenuation of hepatic fibrosis through the regulation of MMPs/TIMPs balance.

Insulin-like growth factor 2 mRNA-binding protein 1 promotes cell proliferation via activation of AKT and is directly targeted by microRNA-494 in pancreatic cancer

BACKGROUND Studies have shown that insulin-like growth factor 2 mRNA-binding protein 1(IGF2BP1)plays critical roles in the genesis and development of human cancers.AIM To investigate the clinical significance and role of IGF2BP1 in pancreatic cancer.METHODS Expression levels of IGF2BP1 and microRNA-494(miR-494)were mined based on Gene Expression Omnibus datasets and validated in both clinical samples and cell lines by quantitative real-time polymerase chain reaction and Western blot.The relationship between IGF2BP1 expression and clinicopathological factors of pancreatic cancer patients was analyzed.The effect and mechanism of IGF2BP1 on pancreatic cancer cell proliferation were investigated in vitro and in vivo.Analyses were performed to explore underlying mechanisms of IGF2BP1 upregulation in pancreatic cancer and assays were carried out to verify the posttranscriptional regulation of IGF2BP1 by miR-494.RESULTS We found that IGF2BP1 was upregulated and associated with a poor prognosis in pancreatic cancer patients.We showed that downregulation of IGF2BP1 inhibited pancreatic cancer cell growth in vitro and in vivo via the AKT signaling pathway.Mechanistically,we showed that the frequent upregulation of IGF2BP1 was attributed to the downregulation of miR-494 expression in pancreatic cancer.Furthermore,we discovered that reexpression of miR-494 could partially abrogate the oncogenic role of IGF2BP1.CONCLUSION Our results revealed that upregulated IGF2BP1 promotes the proliferation of pancreatic cancer cells via the AKT signaling pathway and confirmed that the activation of IGF2BP1 is partly due to the silencing of miR-494.

Interaction between insulin-like growth factor binding protein-related protein 1 and transforming growth factor beta 1 in primary hepatic stellate cells

BACKGROUND: We previously showed that insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) is a novel mediator in liver fibrosis. Transforming growth factor beta 1 (TGF beta 1) is known as the strongest effector of liver fibrosis. Therefore, we aimed to investigate the detailed interaction between IGFBPrP1 and TGF beta 1 in primary hepatic stellate cells (HSCs). METHODS: We overexpressed TGF beta 1 or IGFBPrP1 and inhibited TGF beta 1 expression in primary HSCs for 6, 12, 24, 48, 72, and 96 hours to investigate their interaction and observe the accompanying expressions of a-smooth muscle actin (alpha-SMA), collagen I, fibronectin, and phosphorylated-mothers against decapentaplegic homolog 2/3 (p-Smad2/3). RESULTS: We found that the adenovirus vector encoding the TGF beta 1 gene (AdTGF beta 1) induced IGFBPrP1 expression while that of alpha-SMA, collagen I, fibronectin, and TGF beta 1 increased gradually. Concomitantly, AdIGFBPrP1 upregulated TGF beta 1, alpha-SMA, collagen I, fibronectin, and p-Smad2/3 in a time-dependent manner while IGFBPrP1 expression was decreased at 96 hours. Inhibition of TGF beta 1 expression reduced the IGFBPrP1-stimulated expression of alpha-SMA, collagen I, fibronectin, and p-Smad2/3. CONCLUSIONS: These findings for the first time suggest the existence of a possible mutually regulation between IGFBPrP1 and TGF beta 1, which likely accelerates liver fibrosis progression. Furthermore, IGFBPrP1 likely participates in liver fibrosis in a TGF beta 1-depedent manner, and may act as an upstream regulatory factor of TGF beta 1 in the Smad pathway.

Insulin-like growth factor binding protein-7 induces activation and transdifferentiation of hepatic stellate cells in vitro

AIM:To investigate the role of insulin-like growth factor binding protein-7 (IGFBP-7) in the activation and transdifferentiation of hepatic stellate cells (HSC) in vitro.METHODS:Rat HSC-T6 cells were cultured in separate dishes and treated with various concentration of transforming growth factor (TGF)-β1,IGFBP-7 or antiIGFBP-7 antibody for 24 h.The supernatant or a cytoplasm suspension was obtained from cultured HSC,followed by transfer of cells to form cell-coated dishes.Immunocytochemistry and Western blotting were used to analyze the expression of IGFBP-7 induced by TGF-β1 and the level of fibronectin,collagen and α-smooth muscle actin (SMA).The pro-apoptotic effect of antiIGFBP-7 antibody was determined by flow cytometry.RESULTS:Immunocytochemistry and Western blotting revealed that the expression of IGFBP-7 in TGF-β1 treated HSC was significantly up-regulated compared to that in the control group.In addition,fibronectin,collagen and α-SMA also showed enhanced expression in accordance with the transdifferentiation process in a dose-dependent manner to some extent.Moreover,flow cytometry suggested that anti-IGFBP-7 antibody induced apoptosis of activated HSC,which is responsible for the development of liver fibrosis,and may represent a novel pathway and target for therapeutic intervention.CONCLUSION:IGFBP-7 showed increased expression in activated HSC and played an important role in the activation and transdifferentiation process of HSC.AntiIGFBP-7 antibody may ameliorate liver fibrogenesis.

Significance of highly phosphorylated insulin-like growth factor binding protein-1 and cervical length for prediction of preterm delivery in twin pregnancies

BACKGROUND A twin pregnancy can carry greater risks than singleton pregnancies.About 60 in 100 twin pregnancies result in spontaneous birth before 37 wk,which is associated with several complications in the premature babies.Clinical detection of biomarkers may help to predict the possibility of premature birth so that corresponding interventions can be given to the pregnant women in a timely manner,in order to reduce the risk of preterm birth and improve the outcomes of the newborn infants.AIM To explore the clinical value of transvaginal ultrasound measurement of cervical length combined with insulin-like growth factor binding protein-1(IGFBP-1)hyperphosphorylation in cervical secretions as predictors of preterm delivery in twin pregnancies.METHODS A total of 254 pregnant women with twin pregnancies,who were admitted to Hainan General Hospital and underwent maternity examination,were selected as the study subjects from January 2015 to December 2018.All participants received transvaginal ultrasound measurement of cervical length and phosphorylated IGFBP-1(phIGFBP-1)test between 24 and 34 wk gestation.The pregnancy outcomes were analyzed.RESULTS Of the women with a positive phIGFBP-1 test result,preterm birth rate was higher in those with a cervical length≤25 mm than those with a cervical length>25 mm(all P<0.05).Similarly,in women with a negative phIGFBP-1 test result,preterm birth rate was higher in those with a cervical length≤25 mm than those with a cervical length>25 mm(all P<0.05).The sensitivity,specificity,and positive and negative predictive values of the phIGFBP-1 test combined with the cervical length test were 95.71%,91.21%,95.12%and 92.22%,respectively,for the prediction of preterm birth.CONCLUSION Cervical length combined with phIGFBP-1 tests is of value for the prediction of outcomes of preterm delivery in twin pregnancies.

Insulin-like growth factor binding protein-5 influences pancreatic cancer cell growth

AIM: To investigate the functional significance of insulin-like growth factor binding protein-5 (IGFBP-5) overexpression in pancreatic cancer (PaC).METHODS: The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses. Changes in cell survival and signal transduction were evaluated after mitogen activated protein kinase and phosphatidylinositol 3-kinase (PI3K) inhibitor treatment.RESULTS: After serum deprivation, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 (ERK1/2) activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.CONCLUSION: These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.

Expression of insulin-like growth factor binding protein-2 in gastric carcinoma and its relationship with cell proliferation

AIM: To investigate the expression of insulin-like growth factor binding protein-2 (IGFBP-2) in gastric carcinoma and its clinical significance and to explore its relationship with cell proliferation. METHODS: Expressions of IGFBP-2 and Ki-67 in 118 cases of gastric carcinoma and 40 cases of normal gastric mucosa were detected by EnVision immunohistochemical technique. RESULTS: Expression of IGFBP-2 in gastric carcinoma was higher than that in normal gastric mucosa (P < 0.01). There was no difference between high- and low-grade gastric carcinoma (P > 0.05). Expression of IGFBP-2 in advanced gastric carcinoma was higher than that in early gastric carcinoma (P < 0.05). Expression of IGFBP-2 in gastric carcinoma with lymph node metastasis was higher than that without lymph node metastasis (P < 0.01). IGFBP-2 expression was a positively related to the clinical stage of gastric carcinoma (P < 0.01). There was a positive correlation between IGFBP-2 and Ki-67 (P < 0.05). CONCLUSION: IGFBP-2 may be involved in carcino- genesis and progression of gastric carcinoma by promoting cell proliferation.

A peptide containing the receptor binding site of insulin-like growth factor binding protein-2 enhances bone mass in ovariectomized rats

Male Igfbp2-/-mice have a significant reduction in bone mass and administration of a peptide that contains the insulin-like growth factor binding protein-2(IGFBP-2) receptor-binding domain stimulates bone formation in these animals. Female Igfbp2-/-mice do not have this phenotype but following ovariectomy(OVX) lose more bone than OVX wild-type mice. This suggests that in the absence of estrogen, IGFBP-2 is required to maintain bone mass. Therefore these studies were undertaken to determine if this peptide could stimulate bone acquisition in OVX rats. OVX rats were divided into seven treatment groups: sham animals, OVX animals, OVX animals receiving a control scrambled peptide, or one of three doses of the active peptide termed PEG-HBD-1(0.7, 2,and 6 mg·kg^(-1)) and an OVX group receiving parathyroid hormone(PTH)(50 μg·kg-1 per day). The peptides were administered for8 weeks. DXA revealed a significant reduction in femoral and tibial areal bone mineral density(aBMD) after OVX, whereas treatment with the high-dose peptide increased aBMD by 6.2% ± 2.4%(P < 0.01) compared to control peptide; similar to the increase noted with PTH(5.6% ± 3.0%, P < 0.01). Similar increases were noted with two lower doses of the peptide(3.8% ± 1.5%, P < 0.05 for low dose; 3.1% ± 1.6%, P = 0.07 for middle dose). Micro CT showed that the OVX control peptide animals had reductions of 41% and64% in femoral trabecular BV/TV and trabecular number, respectively. All three doses of the peptide increased bone volume/total volume(BV/TV) significantly, while the low and middle doses increased trabecular number. Cortical BV/TV and thickness at the midshaft increased significantly with each dose of peptide(18.9% ± 9.8%, P < 0.01 and 14.2% ± 7.9%, P < 0.01 for low dose; 23.7% ±10.7%, P < 0.001 and 15.8% ± 6.1%, P < 0.001 for middle dose; 19.0% ± 6.9%, P < 0.01 and 16.2% ± 9.7%, P < 0.001 for high dose)and with PTH(25.8% ± 9.2%, P < 0.001 and 19.4% ± 8.8%, P < 0.001). Histomorphometry showed that the lowest dose of peptide stimulated BV/TV, trabecular thickness, mineral apposition rate(MAR), bone formation rate/bone surface(BFR/BS), number of osteoblasts/bone perimeter(N.ob/B.pm), and decreased osteoclast surface/bone perimeter(Oc.S/B.Pm). The highest dose stimulated each of these parameters except MAR and BFR/BS. Thus, the heparin-binding domain receptor region of IGFBP-2 accounts for its anabolic activity in bone. Importantly, this peptide enhances bone mass in estrogen-deficient animals.

Serum concentrations of insulin-like growth factor-binding protein 5 in Crohn's disease

AIM:To investigate serum insulin-like growth factorbinding protein 5(IGFBP-5)levels and intestinal IGFBP-5expression in patients with Crohn’s disease(CD).METHODS:We analyzed the serum concentrations and intestinal expression of IGFBP-5 in 42 patients with CD,of whom 26 had endoscopically or radiologically proven stricture formation.Nine of the 42 patients had active disease,with a Crohn’s disease activity index>150.Serum IGFBP-5 levels were analyzed in 20 healthy controls matched by sex and age to the CD patients.Serum IGFBP-5 was measured using an enzyme-linked immunosorbent assay.Intestinal tissue was obtained from patients through endoscopic biopsies.IGFBP-5expression was detected using immunohistochemistry and was scored semiquantitatively.RESULTS:The median serum IGFBP-5 concentrations of CD patients were significantly lower compared with healthy controls[median 7.2(IQR:5.5-11.3)ng/mL vs 11.3(8.0-44.6)ng/mL,P<0.001].There was no significant difference between median serum IGFBP-5levels in CD patients with or without stricture formation[6.9(5.5-11.3)ng/mL vs 7.8(5.3-10.1)ng/mL,P=0.815].The serum IGFBP-5 levels were not significantly different between patients with active disease and inactive disease[7.2(6.5-7.6)ng/mL vs 7.2(5.5-11.3)ng/mL,P=0.890].However,a significant correlation was observed between serum IGFBP-5 levels and platelet count(PLT)(r=0.319,P=0.0395).No significant correlation was found between tissue IGFBP-5 immunohistochemical staining intensity scores and serum IGFBP-5 levels.No significant difference was found when comparing the serum IGFBP-5 levels among the patients with different tissue IGFBP-5 staining scores(absent/very weak,weak,moderate or strong).There was a significant correlation between tissue IGFBP-5staining scores and white blood cell count(r=0.391,P=0.01)and PLT(r=0.356,P=0.021).CONCLUSION:Our results indicate that serum IGFBP-5 concentrations were lower in CD patients compared to healthy controls regardless of disease activity or the presence of stricture formation.

Preparatory training attenuates drastic response of the insulin-like growth factor binding protein 1 at the point of maximal oxygen consumption in handball players

Background:Intensive exercise changes physiological need for glucose and several biochemical pathways responsible for its metabolism response.Among them are those which involve insulin,insulin-like growth factor(IGF-1),and IGF-binding proteins(IGFBPs).Different types and degrees of exercise,as well as an athlete's fitness,may induce a range of responses regarding concentrations and time needed for the alteration.The idea of the work was to find out whether and how insulin/IGF axis responds to additional physical activity in the already trained subjects and if so,is the adaptation potentially beneficial from the aspect of metabolic control.Methods:The effect of 4-week intensive training on campus(preparatory training) on the levels of insulin,IGF-1,and IGFBPs during maximal progressive exercise test(MPET) on a treadmill was compared to the results obtained during MPET conducted after a regular training season of a female elite handball team(n = 17,age:17 ± 1 years,height:171 ± 8 cm,weight:65 ± 8 kg,body mass index:22 ± 1 kg/m^2 at the beginning of the study;there were no significant changes at the end).Serum samples were obtained from players immediately before the test(basal),at the end of the test after reaching the point of maximal oxygen consumption(VO_(2max)),and after recovery.Results:The concentration of insulin decreased at VO_(2max),but remained higher in players after preparatory training(12.2 ± 2.5 m U/L vs.8.9 ± 4.4 m U/L,p = 0.049).The level of IGFBP-1 decreased in players at VO_(2max) in either case of training,but it remained much higher in tests performed after the preparatory regime than before(p = 0.029).Concentrations of IGF-1,IGFBP-2,-3,and-4 did not change significantly.Conclusion:The inverse relation between insulin and IGFBP-1 was lost during MPET,as these 2 molecules changed in the same direction.The results obtained suggest less severe stress-induced depression of insulin and IGFBP-1 after preparatory training.But another metabolic mechanism cannot be excluded,and that is potentially impaired insulin sensitivity resulting in higher level of IGFBP-1.

Mendelian randomization provides evidence for a causal effect of serum insulin-like growth factor family concentration on risk of atrial fibrillation

BACKGROUND Atrial fibrillation(AF)is one of the most common persistent arrhythmias among adult cardiovascular diseases.It is important to identify potential risk factors for AF.Members of the insulin-like growth factor(IGF)family exert a variety of effects on various cell types in the context of the pathogenesis of cardiovascular diseases,and previous population-based studies indicate associations between IGF family members and AF.However,the causal effects of IGF family members in AF have not been evaluated.assess genetic relationships between IGF family members and AF.METHODS MR was performed based on genome-wide association study(GWAS)datasets,and concentration levels of 14 IGF family members were retrieved.An initial MR analysis was conducted to identify single nucleotide polymorphisms potentially associated with IGF serum concentrations.A GWAS meta-analysis including 60620 AF cases and 970216 control participants of European ancestry was then conducted to identify AF causal effects.Two-sample MR packages were used to perform MR analysis in R.MR-Egger,weighted median(WM),and inverse va-riance weighted(IVW)methods were used.RESULTS Core Tip:Due to the high prevalence of atrial fibrillation(AF),and adverse outcomes related to it,it is important to identify risk factors associated with development of the condition.Insulin-like growth factor(IGF)family members exert a variety of effects on various cell types in the context of the pathogenesis of cardiovascular diseases,and previous population-based studies indicate associations between IGF family members and AF.However,the causal effects of IGF family members in AF have not been evaluated.The results of the current study provide novel insights on the pathogenesis of AF,and implic-ations of serum IGF family member concentrations when assessing the risk of AF.The study generated evidence on the potential roles of developmental pathological effects in the pathogenesis of AF.Further observational and experimental studies are critically needed.

Modified insulin-like growth factor 1 containing collagen-binding domain for nerve regeneration

Insulin-like growth factor 1 （IGF-I） is a potential nutrient for nerve repair. However, it is impractical as a therapy because of its limited half- life, rapid clearance, and limited target specificity. To achieve targeted and long-lasting treatment, we investigated the addition of a binding structure by fusing a collagen-binding domain to IGF- 1. After confirming its affinity for collagen, the biological activity of this construct was examined by measuring cell proliferation after transfection into PC12 and Schwann cells using a 3-（4,5-dimethyl-2-thiazolyl）-2,5-di- phenyl-2-H-tetrazolium bromide assay. Immunofluorescence staining was conducted to detect neurofilament and microtubule-associated protein 2 expression, while real time-polymerase chain reaction was utilized to determine IGF-1 receptor and nerve growth/actor mRNA expression. Our results demonstrate a significant increase in collagen-binding activity of the recombinant protein compared with IGF-1. Moreover, the recombinant protein promoted proliferation of PC12 and Schwann cells, and increased the expression of neurofilament and microtubule-associated protein 2. Importantly, the recombinant protein also stimulated sustained expression of IGF-1 receptor and nerve growth factor mRNA for days. These results show that the recombinant protein achieved the goal of targeting and long-lasting treatment, and thus could become a clinically used factor for promoting nerve regeneration with a prolonged therapeutic effect.