Insulin-like growth factor 2 targets IGF1R signaling transduction to facilitate metastasis and imatinib resistance in gastrointestinal stromal tumors

BACKGROUND Gastrointestinal stromal tumors(GISTs)are typical gastrointestinal tract neoplasms.Imatinib is the first-line therapy for GIST patients.Drug resistance limits the long-term effectiveness of imatinib.The regulatory effect of insulin-like growth factor 2(IGF2)has been confirmed in various cancers and is related to resistance to chemotherapy and a worse prognosis.AIM To further investigate the mechanism of IGF2 specific to GISTs.METHODS IGF2 was screened and analyzed using Gene Expression Omnibus(GEO:GSE225819)data.After IGF2 knockdown or overexpression by transfection,the phenotypes(proliferation,migration,invasion,apoptosis)of GIST cells were characterized by cell counting kit 8,Transwell,and flow cytometry assays.We used western blotting to evaluate pathway-associated and epithelial-mesenchymal transition(EMT)-associated proteins.We injected transfected cells into nude mice to establish a tumor xenograft model and observed the occurrence and metastasis of GIST.RESULTS Data from the GEO indicated that IGF2 expression is high in GISTs,associated with liver metastasis,and closely related to drug resistance.GIST cells with high expression of IGF2 had increased proliferation and migration,invasiveness and EMT.Knockdown of IGF2 significantly inhibited those activities.In addition,OEIGF2 promoted GIST metastasis in vivo in nude mice.IGF2 activated IGF1R signaling in GIST cells,and IGF2/IGF1R-mediated glycolysis was required for GIST with liver metastasis.GIST cells with IGF2 knockdown were sensitive to imatinib treatment when IGF2 overexpression significantly raised imatinib resistance.Moreover,2-deoxy-D-glucose(a glycolysis inhibitor)treatment reversed IGF2 overexpressionmediated imatinib resistance in GISTs.CONCLUSION IGF2 targeting of IGF1R signaling inhibited metastasis and decreased imatinib resistance by driving glycolysis in GISTs.

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.

SIMULTANEOUS OVER-EXPRESSION OF INSULIN-LIKE GROWTH FACTOR- Ⅱ (IGF- Ⅱ ) AND IGF- Ⅱ RECEPTOR(IGF- Ⅱ R) GENES IN HUMAN PRIMARY CANCER-IMPLICATION OF AUTOCRINE AND PARACRINE MECHANISM IN AUTONOMOUS GROWTH OF HEPATIC CANCER

This is first report about the simultaneous over-expression of both Insulin-like growth factor (IGF- I ) and its receptor (IGF- I R) at mRNA level in human primary hepatic Cancer (PHC). In 10 PHC samples from China, IGF-I and IGF- I R were both over-expressed, whereas only a background signal was detected in normal liver. In 5 pairs of PHC and its non- tumorous adjacent liver tissues from South Africa, IGF- I and IGF- I R were also over-expressed in PHC. mRNA expression of IGF- I in all 5 cases and IGF- I R in 4 of 5 cases were higher in cancer than non- tumorous adjacent liver tissues. These results strongly implicate that an autocrine and/ or paracrine mechanism might be Involved in formation and progression of PHC.

Glycosylation-independent binding to extracellular domains 11-13 of mannose-6-phosphate/insulin-like growth factor-2 receptor mediates the effects of soluble CREG on the phenotypic proliferation of vascular smooth muscle cells

Background The present study aimed to investigate the detailed mode and specific sites for their binding as well as the functional relevance of this binding in the phenotypic proliferation of vascular smooth muscle cells(SMCs). Methods CREG knocked-down SMCs were employed to evaluate the biological activity of wtCREG and mCREG.Expressions of SMC differentiation markers SM myosin heavy chain(SM-MHC),SM-actin,heavy caldesmon and myocardin were determined by Western blotting using specific antibodies. Cellular growth of SMCs was assessed by bromide dewuridine (BrdU) incorporation and cell cycle analysis on fluorescence-activated cell sorting(FACS).A solid-phase binding assay was used to study the binding of CREG to extracellular domains of M6P/IGF2R.The cellular co-localization of the two recombinant CREGs with M6P/IGF2R was detected on SMC surface by immunoprecipitation and immunofluorescence analysis.Results The molecular weight of wtCREG was around 30 kD while that of the mCREG was～25 kD.Treatment of wtCREG with PNGase F reduced its molecular weight from～30 kD to～25 kD,whereas PNGase F treatment had no effect on the molecular weight of mCREG.Both wtCREG and mCREG proteins enhanced SMC differentiation,inhibited BrdU incorporation,and arrested cell cycle progression when added to the culture medium.In CREG knocked-down SMCs,the amount of CREG detected by immunoblotting in M6P/IGF2R immunoprecipitates was significantly reduced when compared to normal cells.Both recombinant CREGs co-immunoprecipitated with M6P/IGF2R, although slightly reduced amount of the mutant CREG was detected in M6P/IGF2R immunoprecipitates.Immunostaining revealed that His-tagged CREGs co-localized with IGF2R on the cell surface in a glycosylation-independent manner.In vitro binding assay showed that CREGs bound to M6P/ IGF2R extracellular domains 7-10 and 11-13 in a glycosylation -dependent and -independent manner,respectively.Further blocking experiments using soluble M6P/IGF2R fragments and M6P/IGF2R neutralizing antibody indicated that the biological activities of recombinant CREGs in SMC growth and the up-regulation of SMC differentiation markers were all abolished by treatment with the M6P/IGF2R neutralizing antibody. However,although the growth inhibitory effect of wtCREG was nearly abolished by D7-10 or D11-13,the effect of mCREG was only reversed by Dll-13,indicating that the binding to domains 11-13 is required for CREG to modulate the proliferation of SMCs.Conclusions These data suggest that solubleCREG proteins can exert their biological function via binding to the extracellular domains 7-10 and 11-13 of cell surface M6P/IGF2R in both a glycosylation-dependent and -independent manner.

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.

RNA interference affects tumorigenicity and expression of insulin-like growth factor-1,insulin-like growth factor-1 receptor,and basic fibroblast growth factor-2 in rat C6 glioma cells

BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.

Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis

Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats.

A predictive score for retinopathy of prematurity by using clinical risk factors and serum insulin-like growth factor-1 levels

AIM：To detect the impact of insulin-like growth factor-1（IGF-1）and other risk factors for the early prediction of retinopathy of prematurity（ROP）and to establish a scoring system for ROP prediction by using clinical criteria and serum IGF-1 levels.METHODS：The study was conducted with 127 preterm infants.IGF-1 levels in the 1st day of life,1st,2nd,3rd and4th week of life was analyzed.The score was established after logistic regression analysis,considering the impact of each variable on the occurrences of any stage ROP.A validation cohort containing 107 preterm infants was included in the study and the predictive ability of ROP score was calculated.RESULTS：Birth weights（BW）,gestational weeks（GW）and the prevalence of breast milk consumption were lower,respiratory distress syndrome（RDS）,bronchopulmonarydysplasia（BPD）and necrotizing enterocolitis（NEC）were more frequent,the duration of mechanical ventilation and oxygen supplementation was longer in patients with ROP（P〈0.05）.Initial serum IGF-1 levels tended to be lower in newborns who developed ROP.Logistic regression analysis revealed that low BW（〈1250 g）,presence of intraventricular hemorrhage（IVH）and formula feeding increased the risk of ROP.Afterwards,the scoring system was validated on 107 infants.The negative predictive values of a score less than 4 were 84.3%,74.7%and 79.8%while positive predictive values were 76.3%,65.5%and71.6%respectively.CONCLUSION：In addition to BW〈1250 g and IVH,formula consumption was detected as a risk factor for the development of ROP.Breastfeeding is important for prevention of ROP in preterm infants.

Antisense oligonucleotide to insulin-like growth factorⅡ induces apoptosis in human ovarian cancer AO cellline

The effects of antisense oligonucleotide to insulin-like growth factor 11 (IGFII) to induce apoptosis in human ovarian cancer cells were evaluated. Antiproliferation effects of antisense to IGFII in ovarian cancer AO cells were determined by 3H-thymidine incorporation. Apoptosis of the IGFll antisense-treated cells was quantitated by both nuclear condensation and flow cytometry after cells were stained with propidium iodide. IGFII antisense (4.5μM)treatment of 48 h maximally inhibited proliferation of AO cells. More than 25% of IGFII antisense-treated cells (4.5PM for 24 h) had undergone apoptosis, whereas less than 3% of the cells were apoptotic in either IGFII sense-treatedcells or untreated cells. Antisense oligonucleotide to IGFII significantly inhibited cell proliferation and induced apoptosis in human ovarian cancer AO cell. These data suggest that IGFII may be a potential target in treatment of ovarian cancer and antisense oligonucleotide to IGFⅡmay serve as a therapeutic approach.

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.

Effect of in ovo folic acid injection on hepatic IGF2 expression and embryo growth of broilers

Background： Insulin-like factor 2（IGF2） plays an important role in embryonic growth process by modulating intermediary metabolism and cell proliferation. Folic acid is involved in one carbon metabolism and contributes to DNA methylation which is related to gene expression. The purpose of this study was to explore whether folic acid could regulate IGF2 expression via epigenetic mechanism and further promote embryonic growth of new-hatched broilers.Methods： In the present study, 360 fertile eggs were selected and randomly assigned to four treatments. On11 embryonic day of incubation（E11）, 0, 50, 100 and 150 μg folic acid were injected into eggs respectively.After hatched, growth performance of broilers were calculated. Hepatic IGF2 expression, methylation level and chromatin structure of promoter region were analyzed.Results： Results have showed that IGF2 expression was up-regulated in 150 μg folic acid group（P 〈 0.05） and other two dose of folic acid did not affect gene expression（P 〉 0.05）. Meanwhile, methylation level of IGF2 promoter were lower in 100 and 150 μg groups, which was consistent with lower expression of DNA methyltransferase1（DNMT1）（P 〈 0.05）. What＇s more, chromatin looseness of IGF2 promoter was higher in 150 μg group than control group（P 〈 0.05）. Further, birth weight（BW）, liver and bursa index of new-hatched chickens in 150 μg folic acid group were higher than the other groups（P 〈 0.05）. There were positive correlations between hepatic IGF2 expression and BW and organs index（P 〈 0.05）.Conclusion： In conclusion, our data have demonstrated that 150 μg folic acid injection on E11 could up-regulate IGF2 expression by modulating DNA hypomethylation and improving chromatin accessibility in the gene promoter region,and ulteriorly facilitate embryonic growth and organ development of broilers.

Genetic expression of Col-2A and Col-10A as a function of administration of IGF-1 &TGF-<i>β</i>with and without anterior mandibular repositioning appliance on the growth of mandibular condylar cartilage in young rabbit

New Zealand (NZ) young rabbits with the administration of insulin-like growth factor (IGF-1) and transforming growth factor-β (TGF-β) with and without mandibular anterior repositioning appliances are explored for the growth of the mandibular condylar cartilage (MCC). 32 growing NZ and rabbits were divided into 4 groups: the group with saline injection in TMJ, the group which received growth factor injection in TMJ, the group which received anterior positioning appliance and the group which received growth factors injection as well as mandibular repositioning appliance. Gene expression was studied by real-time RT-PCR and cartilage growth by histomorphometry. Administration of growth factors along with mandibular repositioning appliances has induced 1) 1.70-fold expression of Col-2Agene (p value < 0.0005) and 2) 1.47-fold expression of Col-10Agene (p value < 0.0005). In contrast, administration of only mandibular repositioning appliances induced 1) 1.28-fold expression of Col-2Agene (p value < 0.0005) and 2) merely 0.62-fold expression of Col-10Agene (p value < 0.0005), while administration of growth factors only induced 1) mere 0.56-fold expression of Col-2Agene (p value 10A gene (p value growth factors along with mandibular repositioning appliances causes an increase in genetic expressions which have been corroborated by histomorphometry and validated by statistical analysis, during an accelerated growth of mandibular condylar cartilage. Administration of growth factors in the TMJ could provide a synergistic role along with mandibular repositioning appliances for treatment of mandibular retrognathism as well as disorders on the MCC.

孕妇血清IGF-1、IGF-2、IGFBP-3水平与正常胎儿生长的相关性

目的探讨孕妇血清胰岛素样生长因子1(insulin like growth factor 1,IGF-1)、IGF-2、IGF结合蛋白3(IGF binding protein 3,IGFBP-3)与正常胎儿生长的关系。方法选择2010年1月至2011年5月于上海市浦东新区人民医院产前检查并分娩正常体重儿的初产妇66例,分为妊娠16～18周、妊娠26～28周、妊娠37～40周3个阶段进行纵向观察,放射免疫法测定孕妇各阶段血清中IGF-1、IGF-2、IGFBP-3水平并进行对比分析。结果孕期母血IGF-1水平随着孕周增加明显上升,其中IGF-1水平在妊娠37～40周高于妊娠26～28周,妊娠26～28周高于妊娠16～18周,差异均有显著统计学意义(P均<0.01)。孕期母血IGF-2水平随孕周增加无明显改变,妊娠3阶段差异无统计学意义(P>0.05)。母血IGFBP-3水平妊娠37～40周高于妊娠26～28周及妊娠16～18周期,差异有统计学意义(P<0.05),而妊娠26～28周与妊娠16～18周无显著差异。妊娠16～18周、26～28周和37～40周3阶段母血IGF-1、IGF-2、IGFBP-3水平与正常新生儿出生体重无显著相关性。结论孕妇血清IGF-1、IGFBP-3水平与正常胎儿生长密切相关,IGF-1可作为临床评价不同阶段正常胎儿生长的指标,而IGFBP-3更多地反映了妊娠中晚期正常胎儿的生长。

IGFBP-2、-3在卵巢上皮性癌患者血液和卵巢肿瘤组织中的表达及临床意义

目的探讨胰岛素样生长因子(IGF)结合蛋白2,3(IGFBP-2,-3)在卵巢上皮性癌(简称卵巢癌)患者血液和卵巢肿瘤组织中的表达,及其与卵巢癌临床病理学特征的关系。方法采用Western ligand blot和Western blot检测卵巢肿瘤患者及正常对照者(卵巢良性肿瘤10例,交界性肿瘤6例,卵巢癌10例,正常对照者10例)血清中IGFBP-2、IGFBP-3及IGF-Ⅱ含量;免疫组织化学染色检测正常卵巢组织(4例)和卵巢肿瘤组织中(卵巢良性肿瘤8例,卵巢交界性肿瘤8例,卵巢癌23例,包括中度和高度分化者15例,低度分化者8例)IGFBP-2,-3的表达。结果卵巢癌患者血清大片段以及成熟IGF-Ⅱ均明显降低,IGFBP-2水平明显升高,而IGFBP-3含量明显降低甚至消失,与相应正常对照组、良性或交界性组相比差异均有统计学意义(P<0.001或P<0.01)。免疫组织化学染色结果显示卵巢癌IGFBP-2的表达明显升高(P<0.0001或P<0.005),且随着卵巢癌组织分化程度的降低,IGFBP-2的表达呈增强趋势;而IGFBP-3的表达随着卵巢癌细胞分化程度的降低,明显降低或呈阴性表达(P<0.05)。结论卵巢癌患者血循环中IGFBP-3降解以及IGFBP-2明显升高的状况有可能导致IGF-Ⅱ生物学功能改变,并与卵巢癌的临床病理学特征有明显的相关性。

牛初乳短链IGF-Ⅰ对STZ糖尿病大鼠心肌细胞Ca^(2+)的影响

为了解牛初乳短键类胰岛素样生长因子-I（IGF－I）对糖尿病大鼠心肌细胞Ca2+的影响，我们用牛初乳短键IGF－I治疗涟豚佐菌素（STZ）糖尿病大鼠。利用原子光谱吸收法测定发现STZ糖尿病大鼠心肌细胞Ca2+的含量明显高于正常对照组[分别为（54．5±9．6）及（24．4±80）μg/g心肌]；牛初乳短键IGF－I口服（15μg／kg体重）或腹腔注射（250ng/kg体重）治疗5周后的糖尿病大鼠血清IGF一I浓度有显著增加，心肌细胞Ca2+含量显著降低［分别为（37．3±14．5）及（27．5±9．7）μg／g心肌]，达正常水平。提示牛初乳短链IGF－I能逆转糖尿病时心肌细胞Ca2+超载现象，为糖尿病心肌病变提供了一种可能的预防措施。

支气管肺炎患儿治疗前后血清IGF-Ⅱ、IL-2、IL-10和TNF-α检测的临床意义

目的:探讨支气管肺炎患儿治疗前后血清IGF-Ⅱ、IL-2、IL-10和TNF-α含量的变化。方法:分别应用放免法和酶免法对62例支气管肺炎患儿进行了治疗前后血清IGF-Ⅱ、IL-2、IL-10和TNF-α水平检测,并与30例正常健康儿作比较。结果:治疗前血清IGF-Ⅱ、TNF-α水平非常显著高于正常儿组(P<0.01),而IL-2、IL-10则显著低于正常儿组(P<0.01),经治疗后7d,血清IGF-Ⅱ、IL-2、IL-10和TNF-α则与正常儿比较无显著性差异(P>0.05)。结论:检测支气管肺炎患儿血清IGF-Ⅱ、IL-2、IL-10和TNF-α水平的变化对诊断治疗和预后均有一定的临床实用价值。

PHCC合并2型糖尿病患者血清中IGF-1、FPG、AFP的改变及其临床意义

目的探讨胰岛素样生长因子-1(IGF-1)、空腹血糖(FPG)、甲胎蛋白(AFP)在原发性肝癌(PHCC)合并2型糖尿病患者血清中的改变及其临床意义。方法收集正常人群组、2型糖尿病组、PHCC组和PHCC合并2型糖尿病组人群基本资料及血液样本,检测外周血IGF-1、FPG、AFP水平的变化;并对PHCC合并2型糖尿病组患者治疗前后血清IGF-1、AFP水平变化进行分析。结果与正常人群组、2型糖尿病组及PHCC组相比,PHCC合并2型糖尿病组患者血清IGF-1水平降低,差异有统计学意义(P<0.05),且期别越晚IGF-1水平越低。与正常人群组相比,PHCC组、PHCC合并2型糖尿病组患者血清FPG、AFP水平均升高,差异有统计学意义(P<0.05)。与同期治疗前相比,治疗后PHCC合并2型糖尿病组患者外周血清IGF-1水平升高,AFP水平降低,差异有统计学意义(P<0.05)。结论PHCC患者血清IGF-1水平低于正常人群,PHCC合并2型糖尿病组患者血清IGF-1水平低于正常人群及2型糖尿病组患者,IGF-1可作为2型糖尿病患者肝癌发生的预测指标。

膀胱癌中IGF-2和H19基因特异表达模式及印记缺失分析

目的:探讨胰岛素样生长因子-2(IGF-2)和H19等位基因在膀胱癌中特异性表达的模式及基因组印记丢失的分析。方法:结合PCR和限制性片段长度多态性分析RFLP技术以及DNA甲基化检测技术分析我院收集的膀胱癌标本IGF-2和H19等位基因进行杂合子筛选并进一步研究基因印记缺失与膀胱癌两者之间的关系。结果:在40例膀胱癌中IGF-2等位基因筛选出21例杂合子现象的标本,在这21例杂合子标本中有12例发生了基因组印记缺失;H19等位基因筛选出19例杂合子现象的标本,在这19例杂合子标本中有10例发生了基因组印记缺失。H19基因缺失现象与H19DMR区域的高度去甲基化正相关,而IGF-2基因缺失现象与H19DMR区域的高度甲基化正相关。结论:膀胱癌中IGF-2和H19的基因印记缺失与H19DMR区域的甲基化状态有高度的相关性。

2型糖尿病患者血IGF-1与TNF-α相关性评估

目的 :探讨在2型糖尿病患者血中胰岛素样生长因子 -1(Insulinlikegrowthfactory -1,IGF -1)与肿瘤坏死因子 -α(Tumornecrosisfactory -α,TNF -α)浓度关系。方法 :分别测定78例2型糖尿病患者和52例健康对照组血浆IGF -1浓度 ,TNF -α浓度 ,基础胰岛素水平 ,空腹血糖值 ,分别作统计学比较。结果 :2型糖尿病组与健康对照组IGF -1及TNF -α均有明显差别(P<0.01) ,但2型糖尿病组血IGF -1水平与TNF -α浓度之间无明显相关性 (P>0.01)。结论 :血浆IGF -1与TNF -α可能与2型糖尿病患者中胰岛素抵抗相关 ,可能在2型糖尿病发病中起作用 ,但2型糖尿病患者血浆IGF -1与TNF -α之间无平行相关关系。

FSS、IGF-1、Hcy及SF与2型糖尿病外周动脉疾病的关系

目的探讨2型糖尿病(T2DM)患者血清铁蛋白(SF)、同型半胱氨酸(Hcy)、空腹生长抑素(FSS)、胰岛素样生长因子-1(IGF-1)与外周动脉病变(PAD)的关系。方法选取北京天坛医院内分泌科2014年6月至2016年10月收治的160例确诊T2DM患者进行研究,根据踝臂指数(ABI)分组:ABI范围1.0~1.4的患者124例(非PAD组)、ABI范围<1.0的患者46例(PAD组),比较两组患者的血清SF、Hcy、FSS、IGF-1等指标。结果 PAD组患者的年龄、性别、病程、体重指数(BMI)、吸烟率、空腹血糖(FBG)水平与非PAD组比较,差异局均无统计学意义(P>0.05);PAD组患者的收缩压、舒张压、糖化血红蛋白(HbA1c)、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)水平与非PAD组比较,差异均有统计学意义(P<0.05);PAD组患者的血清SF、FSS、IGF-1水平与非PAD组比较,差异均有统计学意义(P<0.05);PAD组的Hcy水平与非PAD组比较,差异局均无统计学意义(P>0.05)。采用多元Logistic回归分析结果显示:收缩压、舒张压、HbA1c、HDL-C、SF、IGF-1增高是T2DM患者并发PDA的独立危险因素(P<0.05),FSS、HDL-C水平升高是T2DM患者并发PDA的保护因素(P<0.05)。结论 PAD患者与健康人收缩压、舒张压、HbA1c、TC、TG、HDL-C、LDL-C水平有显著差异,SF、IGF-1、HbA1c、FSS水平升高提示PAD在发生发展。