Vascular endothelial growth factor/connective tissue growth factor and proteomic analysis of aqueous humor after intravitreal conbercept for proliferative diabetes retinopathy

AIM:To investigate the role of connective tissue growth factor(CTGF)and vascular endothelial growth factor(VEGF)in the protein profile of the aqueous humor in patients with proliferative diabetic retinopathy(PDR)following intravitreal injection of conbercept.METHODS:This study included 72 PDR patients and 8 cataract patients as controls.PDR patients were divided into 3 groups according to the intervals of 3,5,and 7d between intravitreal conbercept(IVC,0.5 mg/0.05 mL)injection and pars plana vitrectomy(PPV)performed.Aqueous humor samples were collected before and after IVC and PPV for VEGF and CTGF levels detected with enzyme-linked immunosorbent assay(ELISA).The differential proteomics of 10 patients who underwent PPV surgery 5d after IVC and 8 normal controls was studied,Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were performed on the data,and the protein interaction network of 23 differential proteins was studied.RESULTS:Post-IVC,VEGF levels decreased and CTGF levels increased significantly in aqueous humor,with the CTGF/VEGF ratio rising significantly at all intervals.Liquid chromatography tandem mass spectrometry(LC-MS/MS)identified differentially expressed proteins between preand post-IVC samples.GO and KEGG analyses revealed involvement in immune response,stress response,complement and coagulation cascades,ferroptosis,and PPAR signaling pathways.PPI analysis highlighted key proteins like APOA1,C3,and transferrin(TF).ELISA assay confirmed the differential expression of proteins such as HBA1,SERPINA1,COL1A1,and ACTB,with significant changes in the IVC groups.CONCLUSION:The study demonstrates that IVC effectively reduces VEGF levels while increasing CTGF levels,thereby modifying the CTGF/VEGF ratio,and IVC significantly alters the protein profile in the aqueous humor of patients with PDR.Proteomic analysis reveals that these changes are associated with critical biological pathways and protein interactions involved in immune response,stress response,and cellular metabolism.

Impact of umbelliprenin-containing niosome nanoparticles on VEGF-A and CTGF genes expression in retinal pigment epithelium cells

AIM:To investigate the impact of niosome nanoparticles carrying umbelliprenin(UMB),an anti-angiogenic and anti-inflammatory plant compound,on the expression of vascular endothelial growth factor(VEGF-A)and connective tissue growth factor(CTGF)genes in a human retinal pigment epithelium(RPE)-like retina-derived cell line.METHODS:UMB-containing niosomes were created,optimized,and characterized.RPE-like cells were treated with free UMB and UMB-containing niosomes.The IC_(50)values of the treatments were determined using an MTT assay.Gene expression of VEGF-A and CTGF was evaluated using real-time polymerase chain reaction after RNA extraction and cDNA synthesis.Niosomes’characteristics,including drug entrapment efficiency,size,dispersion index,and zeta potential were assessed.Free UMB had an IC_(50)of 96.2μg/mL,while UMB-containing niosomes had an IC_(50)of 25μg/mL.RESULTS:Treatment with UMB-containing niosomes and free UMB resulted in a significant reduction in VEGF-A expression compared to control cells(P=0.001).Additionally,UMB-containing niosomes demonstrated a significant reduction in CTGF expression compared to control cells(P=0.05).However,there was no significant reduction in the expression of both genes in cells treated with free UMB.CONCLUSION:Both free UMB and niosome-encapsulated UMB inhibits VEGF-A and CTGF genes expression.However,the latter demonstrates significantly greater efficacy,potentially due to the lower UMB dosage and gradual delivery.These findings have implications for anti-angiogenesis therapeutic approaches targeting age-related macular degeneration.

Transforming growth factor-β and fibrosis

Transforming growth factor-β （TGF-β）, a prototype of multifunctional cytokine, is a key regulator of extracellular matrix （ECM） assembly and remodeling. Specifically, TGF-β isoforms have the ability to induce the expression of ECM proteins in mesenchymal cells, and to stimulate the production of protease inhibitors that prevent enzymatic breakdown of the ECM. Elevated TGF-β expression in affected organs, and subsequent deregulation of TGF-β functions, correlates with the abnormal connective tissue deposition observed during the onset of fibrotic diseases. During the last few years, tremendous progress has been made in the understanding of the molecular aspects of intracellular signaling downstream of the TGF-β receptors. In particular, Smad proteins, TGF-β receptor kinase substrates that translocate into the cell nucleus to act as transcription factors, have been studied extensively. The role of Smad3 in the transcriptional regulation of type I collagen gene expression and in the development of fibrosis, demonstrated both/n vitro and in animal models with a targeted deletion of Smad3, is of critical importance because it may lead to novel therapeutic strategies against these diseases. This review focuses on the mechanisms underlying Smad modulation of fibrillar collagen expression and how it relates to fibrotic processes.

Expression of connective tissue growth factor in tumor tissues is an independent predictor of poor prognosis in patients with gastric cancer

AIM: To examine the expression of connective tissue growth factor (CTGF), also known as CCN2, in gastric carcinoma (GC), and the correlation between the expression of CTGF, clinicopathologic features and clinical outcomes of patients with GC. METHODS: One hundred and twenty-two GC patients were included in the present study. All patients were followed up for at least 5 years. Proteins of CTGF were detected using the Powervision two-step immunostaining method. RESULTS: Of the specimens from 122 GC patients analyzed for CTGF expression, 58 (58/122, 47.5%) had a high CTGF expression in cytoplasm of gastric carcinoma cells and 64 (64/122, 52.5%) had a low CTGF expression. Patients with a high CTGF expression showed a higher incidence of lymph node metastasis than those with a low CTGF expression (P = 0.032). Patients with a high CTGF expression had significantly lower 5-year survival rate than those with a low CTGF expression (27.6% vs 46.9%, P = 0.0178), especially those staging Ⅰ+Ⅱ+Ⅲ (35.7% vs 65.2%, P = 0.0027). CONCLUSION: GC patients with an elevated CTGF expression have more lymph node metastases and a shorter survival time. CTGF seems to be an independent prognostic factor for the successful differentiation of high-risk GC patients staging Ⅰ+Ⅱ+Ⅲ. Over-expression of CTGF in human GC cells results in an increased aggressive ability.

Role of transforming growth factor-beta signaling pathway in pathogenesis of benign biliary stricture

AIM: To characterize the expression of members of the transforming growth factor-beta (TGF-β)/Smad/ connective tissue growth factor (CTGF) signaling pathway in the tissue of benign biliary stricture, and to investigate the effect of TGF-β signaling pathway in the pathogenesis of benign biliary stricture. METHODS: Paraffin embedded materials from 23 cases of benign biliary stricture were analyzed for members of the TGF-β/Smad/CTGF signaling pathway. TGF-β_1, TβRⅠ, TβRⅡ, Smad4, Smad7 and CTGF protein were detected by immunohistochemical strepto-advidinbiotin complex method, and CTGF mRNA was evaluated by hybridization in situ, while 6 cases of normal bile duct served as controls. The percentages of positive cells were counted. The correlation between TGF-β_1, Smad4 and CTGF was analyzed. RESULTS: The positive expression ratios of TGF-β_1, TβRⅠ , TβRⅡ , Smad4, CTGF and CTGF mRNA in 23 cases with benign biliary stricture were 91.3%, 82.6%, 87.0%, 78.3%, 82.6% and 65.2%, respectively, signifi cantly higher than that in 6 cases of normal bile duct respectively (vs 33.3%, 16.7%, 50.0%, 33.3%, 50.0%, 16.7%, respectively, P < 0.05). The positiveexpression ratio of Smad7 in cases with benign biliary stricture was 70.0%, higher than that in normal bile duct, but this difference is not statistically signifi cant 70.0% vs 50%, P > 0.05). There was a positive correlation between positive expression of TGF-β_1, Smad4 and CTGF in cases with benign biliary stricture. CONCLUSION: The high expression of TGF-β/Smad/ CTGF signaling pathway plays an important role in the pathogenesis of benign biliary stricture.

Connective tissue growth factor is overexpressed in human hepatocellular carcinoma and promotes cell invasion and growth

AIM:To determine the expression characteristics of connective tissue growth factor(CTGF/CCN2) in human hepatocellular carcinoma(HCC) in histology and to elucidate the roles of CCN2 on hepatoma cell cycle progression and metastasis in vitro.METHODS:Liver samples from 36 patients(who underwent hepatic resection for the first HCC between 2006 and 2011) and 6 normal individuals were examined for transforming growth factor β1(TGF-β1) or CCN2 mRNA by in situ hybridization.Computer image analysis was performed to measure integrated optimal density of CCN2 mRNA-positive cells in carcinoma foci and the surrounding stroma.Fibroblast-specific protein-1(FSP-1) and E-cadherin were examined to evaluate the process of epithelial to mesenchymal transition,α-smooth muscle actin and FSP-1 were detected to identify hepatic stellate cells,and CD34 was measured to evaluate the extent of vascularization in liver tissues by immunohistochemical staining.CCN2 was assessed for its stimulation of HepG2 cell migration and invasion using commercial kits while flow cytometry was used to determine CCN2 effects on HepG2 cell-cycle.RESULTS:In situ hybridization analysis showed that TGF-β1 mRNA was mainly detected in connective tissues and vasculature around carcinoma foci.In comparison to normal controls,CCN2 mRNA was enhanced 1.9-fold in carcinoma foci(12.36 ± 6.08 vs 6.42 ± 2.35) or 9.4-fold in the surrounding stroma(60.27 ± 28.71 vs 6.42 ± 2.35),with concomitant expression of CCN2 and TGF-β1 mRNA in those areas.Epithelial-mesenchymal transition phenotype related with CCN2 was detected in 12/36(33.3%) of HCC liver samples at the edges between carcinoma foci and vasculature.Incubation of HepG2 cells with CCN2(100 ng/mL) resulted in more of the cells transitioning into S phase(23.85 ± 2.35 vs 10.94 ± 0.23),and induced a significant migratory(4.0-fold) and invasive(5.7-fold) effect.TGF-β1-induced cell invasion was abrogated by a neutralizing CCN2 antibody showing that CCN2 is a downstream mediator of TGF-β1-induced hepatoma cell invasion.CONCLUSION:These data support a role for CCN2 in the growth and metastasis of HCC and highlight CCN2 as a potential novel therapeutic target.

Connective tissue growth factor hammerhead ribozyme attenuates human hepatic stellate cell function

AIM： To determine the effect of hammerhead ribozyme targeting connective tissue growth factor （CCN2） on human hepatic stellate cell （HSC） function.METHODS： CCN2 hammerhead ribozyme cDNA plus two self-cleaving sequences were inserted into pTriEx2 to produce pTriCCN2-Rz. Each vector was individually transfected into cultured LX-2 human HSCs, which were then stimulated by addition of transforming growth factor （TGF）-β1 to the culture medium. Semiquantitative RT-PCR was used to determine mRNA levels for CCN2 or collagen I, while protein levels of each molecule in cell /ysates and conditioned medium were measured by ELISA. Cell-cycle progression of the transfected cells was assessed by flow cytometry.RESULTS： In pTriEx2-transfected LX-2 cells, TGF-β1 treatment caused an increase in the mRNA level for CCN2 or collagen I, and an increase in produced and secreted CCN2 or extracellular collagen I protein levels, pTriCCN2-Rz-transfected LX-2 cells showed decreased basal CCN2 or collagen mRNA levels, as well as produced and secreted CCN2 or collagen I protein. Furthermore, the TGF-β1-induced increase in mRNA or protein for CCN2 or collagen I was inhibited partially in pTriCCN2-Rz-transfected LX-2 cells. Inhibition of CCN2 using hammerhead ribozyme cDNA resulted in fewer of the cells transitioning into S phase.CONCLUSION： Endogenous CCN2 is a mediator of basal or TGF-β1-induced collagen I production in human HSCs and regulates entry of the cells into S phase.

Research progress on the role of connective tissue growth factor in fibrosis of diabetic retinopathy

Diabetic retinopathy（DR） is one of the most important types of diabetic microangiopathy, which is a specific change of fundus lesions and is one of the most serious complications of diabetes. When DR develops to proliferative DR, the main factors of decreasing vision, and even blindness, include retinal detachment and vitreous hemorrhage caused by contraction of blood vessels by fiber membrane. Recent studies reported that the formation of fiber vascular membrane is closely related to retinal fibrosis. The connective tissue growth factor（CTGF） is a cytokine that is closely related to DR fibrosis. However, its mechanism is poorly understood. This paper summarizes the recent studies about CTGF on DR fibrosis for a comprehensive understanding of the role and mechanism of CTGF in PDR.

Interference of Y-27632 on the signal transduction of transforming growth factor beta type 1 in ocular Tenon capsule fibroblasts

AIM: To investigate the interfering effect of Y-27632, a ROCK-I selective inhibitor, on the signal transduction pathway of transforming growth factor-beta 1 (TGF-beta 1) in ocular Tenon capsule fibroblasts (OTFS) in vitro. METHODS: After OTFS from passages 4 to 6 47 vitro were induced by TGF-beta 1 and then treated by Y-27632, the changes of the OTFS cell cycles were analyzed via flow cytometry, and the proteins expression of the alpha -smooth muscular actin (alpha -SMA), connective tissue growth factor (CTGF), collagen I were calculated by Western blot. After OTFS treated by the different concentrations of Y-27632, the expression levels of the alpha -SMA, CTGF and collagen I mRNA were assayed by RT-PCR. RESULTS: Y-27632 had no markedly effect on the OTFS cell cycles. After treated by TGF-beta 1, OTFS in G1 period significantly increased. The cell cycles distribution by both TGF-beta 1 and Y-27632 had no remarkable difference from that in control group. Y-27632 significantly inhibited the proteins expressions of both alpha -SMA and CTGF, while to some extent inhibited that of collagen I. TGF-beta 1 significantly promoted the proteins expressions of alpha -SMA, CTGF and collagen I. After OTFS treated by both TGF-beta 1 and Y-27632, of alpha -SMA, the protein expression was similar with that in control group (P=0.066>0.05), but the protein expression of CTGF or collagen I, respectively, was significantly different from that in control group (P=0.000<0.01). The differences of expressions of the alpha -SMA, CTGF and collagen I mRNA in 30, 150, 750 mu mol/L Y-27632 group were statistically significant, compared with those in control group, respectively (alpha -SMA, P=0.002, 0.000, 0.000; CTGF, P=0.014, 0.002, 0.001; collagen I,P=0.003, 0.002, 0.000). CONCLUSION: Blocking the Rho/ROCK signaling pathway by using of Y-27632 could inhibit the cellular proliferation and the expression of both CTGF and alpha -SMA whatever OTFS induced by TGF-beta 1 or not. Y-27632 suppressed the expression of collagen I mRNA without induction.

Connective tissue growth factor reacts as an IL-6/STAT3-regulated hepatic negative acute phase protein

AIM:To investigate the mechanisms involved in a possible modulator role of interleukin(IL) -6 signalling on CYR61-CTGF-NOV(CCN) 2/connective tissue growth factor(CTGF) expression in hepatocytes(PC) and to look for a relation between serum concentrations of these two parameters in patients with acute inflammation. METHODS:Expression of CCN2/CTGF,p-STAT3,p-Smad 3/1 and p-Smad2 was examined in primary freshly isolated rat or cryo-preserved human PC exposed to various stimuli by Western blotting,electrophoretic mobility shift assay(EMSA) ,reporter-gene-assays and reversetranscriptase polymerase chain reaction. RESULTS:IL-6 strongly down-regulated CCN2/CTGF protein and mRNA expression in PC,enhanceable by extracellular presence of the soluble IL-6 receptor gp80,and supported by an inverse relation between IL-6 and CCN2/CTGF concentrations in patients'sera.The inhi-bition of TGFβ1 driven CCN2/CTGF expression by IL-6 did not involve a modulation of Smad2(and Smad1/3) signalling.However,the STAT3 SH2 domain binding peptide,a selective inhibitor of STAT3 DNA binding activity,counteracted the inhibitory effect of IL-6 on CCN2/CTGF expression much more pronounced than pyrrolidine-dithiocarbamate,an inhibitor primarily of STAT3 phosphorylation.An EMSA confirmed STAT3 binding to the proposed proximal STAT binding site in the CCN2/CTGF promoter. CONCLUSION:CCN2/CTGF is identified as a hepatocellular negative acute phase protein which is downregulated by IL-6 via the STAT3 pathway through interaction on the DNA binding level.

Association of Plasma Connective Tissue Growth Factor Levels with Hyperthyroid Heart Disease

Hyperthyroid heart disease(HHD)is one of the most severe complications of overt hyperthyroidism and increases the risk of mortality in affected patients.Early identification of patients at a higher risk of developing HHD can improve clinical outcomes through active surveillance and management.Connective tissue growth factor(CTGF),a secreted extracellular protein,plays a significant role in cardiac remodeling and dysfunction.We aimed to investigate the association between plasma CTGF level and the risk of HHD in this study.A total of 142 overt hyperthyroid patients without HHD and 99 patients with HHD were included.The plasma CTGF levels were measured using ELISA kits.Routine clinical medical data and echocardiography parameters were recorded for analysis.The plasma CTGF level was significantly higher in patients with HHD than in those without HHD(P=0.002).The plasma CTGF level was positively correlated with free triiodothyronin,tryrotropin receptor antibody,troponin I and lactate dehydrogenase levels and the left atrium diameters,right atrium diameters,and right ventricular end-diastolic diameters(all P<0.05).Logistic regression analysis showed that quartiles 3 and 4 of plasma CTGF levels were significantly associated with the increased risk of HHD(crude OR:2.529;95%CI:1.188-5.387).However,after adjustment for the potentially confounding variables,quartile 4 alone was significantly associated with the higher risk of HHD relative to quartile I.Hyperthyroid patients with HHD display higher plasma CTGF levels.Furthermore,CTGF is an independent risk factor for HHD.Therefore,the plasma CTGF level may be a potential biomarker for the risk of HHD.

Role of Connective Tissue Growth Factor in Extracellular Matrix Degradation in Renal Tubular Epithelial Cells

In order to investigate the effects of connective tissue growth factor （CTGF） antisense oligodeoxynucleotide （ODN） on plasminogen activator inhibitor-1 （PAI-1） expression in renal tubular cells induced by transforming growth factor β1 （TGF-β1） and to explore the role of CTGF in the degradation of renal extracellular matrix （ECM）, a human proximal tubular epithelial cell line （HKC） was cultured in vitro. Cationic lipid-mediated CTGF antisense ODN was transfected into HKC. After HKC were stimulated with TGF-β1 （5 μg/L）, the mRNA level of PAI-1 was detected by RT-PCR. Intracellular PAI-1 protein synthesis was assessed by flow cytometry. The secreted PAI-1 in the media was determined by Western blot. The results showed that TGF-β1 could induce tubular CTGF and PAI-1 mRNA expression. The PAI-1 mRNA expression induced by TGF-β1 was significantly inhibited by CTGF antisense ODN. CTGF antisense ODN also inhibited intracellular PAI-1 protein synthesis and lowered the levels of PAI-1 protein secreted into the media. It was concluded that CTGF might play a crucial role in the degradation of excessive ECM during tubulointerstitial fibrosis, and blocking the biological effect of CTGF may he a novel way in preventing renal fibrosis.

Expression of Connective Tissue Growth Factor in Renal Tubulointerstitial Fibrosis in Rats and Its Pathogenic Role

Summary： In order to explore the role of connective tissue growth factor （CTGF） in the pathogenesis of renal tubulointerstitial fibrosis, 48 Wistar rats were randomly divided into sham-operated and unilateral ureteral obstruction （UUO） group. On the postoperative day 1, 3, 7 and 14, the rats were killed and the kidneys were removed. The renal tubulointerstitial injury index was evaluated according to the MASSON staining. The mRNA levels of CTGF, transforming growth factor β1 （TGF-β1）. collagen [ （col I ）, and plasminogen activator inhibitor-1 （PAI 1） were detected using rexerse transcriptional-polymerase chain reaction （RT PCR）. Immunohistochemistry was performed to evaluale the protein expression of the above factors, and the relations among them were analyzed. Quantitative expression of CTGF protein in the kidneys was also assessed using Western blot. The results showed that TGF-β1 mRNA level was increased at first day after UUO, followed by a marked elevation of CTGF mRNA level, which began to increase 3 days after UUO （P〈0.01）. With the progression of the disease, the mRNA expression of CTGF, col I and PAI-1 was increased progressively. Immunohistochemistry revealed that the CTGF protein expression was significantly increased in fibrotic areas and tubular epithelial cells 3 days after UUO. On the post-UUO day 7, the protein level of CTGF was positively related to the renal tubulointerstitial injury index （r =0.62, P〈0.01）, the expression of TGF-β1 （r=0.85, P〈0.01）, colI （r=0.78, P〈0.01）, and PAI-1（r=0.76, P〈0.01）. Upon Western blot analysis, CTGF protein expression began to increase 3 days after UUO, and appeared progressively throughout the time course （P〈0.01, as compared with sham-operated group）. It is concluded that CTGF can be induced by TGF-β and mediate various profibrotic actions of this cytokine, such as increasing extracellular matrix （ECM） synthesis and decreasing ECM degradation. The increased expression of CTGF may play a crucial role in the development and progression of tubulointerstitial fibrosis.

Clinical significance of connective tissue growth factor in hepatitis B virus-induced hepatic fibrosis

AIM:To determine the utility of connective tissue growth factor(CCN2/CTGF) for assessing hepatic fibrosis in hepatitis B virus(HBV)-induced chronic liver diseases(CLD-B).METHODS:Enzyme-linked immunosorbent assay was used to measure CCN2 in sera from 107 patients with chronic hepatitis B(CHB) and 39 patients with HBVinduced active liver cirrhosis and 30 healthy individuals.Liver samples from 31 patients with CHB,8 patients with HBV-induced liver cirrhosis and 8 HBV carriers with normal liver histology were examined for transforming growth factor β-1(TGF-β1) or CCN2 mRNA levels by in situ hybridization,and computer image analysis was performed to measure integrated optimal density(IOD) of CCN2 mRNA-positive cells in liver tissues.Histological inflammation grading and fibrosis staging were evaluated by H and E staining and Van Gieson's method.RESULTS:Serum CCN2 concentrations were,respectively,4.0-or 4.9-fold higher in patients with CHB or active liver cirrhosis as compared to healthy individuals(P < 0.01).There was good consistency between the levels of CCN2 in sera and CCN2 mRNA expression in liver tissues(r = 0.87,P < 0.01).The levels of CCN2 in sera were increased with the enhancement of histological fibrosis staging in patients with CLD-B(r = 0.85,P < 0.01).Serum CCN2 was a reliable marker for the assessment of liver fibrosis,with areas under the receiver operating characteristic(ROC) curves(AUC) of 0.94 or 0.85 for,respectively,distinguishing normal liver controls from patients with F1 stage liver fibrosis or discriminating between mild and significant fibrosis.CONCLUSION:Detection of serum CCN2 in patients with CLD-B may have clinical significance for assessment of severity of hepatic fibrosis.

The Effect of Connective Tissue Growth Factor on Human Renal Tubular Epithelial Cell Transdifferentiation

To investigate the role of connective tissue growth factor (CTGF) in transdifferentiation of human renal tubular epithelial cell (HKC), in vitro cultured HKC cells were divided into 3 groups: negtive control, low dose CTGF-treated group (rh CTGF, 2.5 ng/ml) and high dose CTGF-treated (rhCTGF, 5.0 ng/ml). Then the expression of α-smooth muscle actin (α-SMA) were assessed by indirect immuno-fluorescence, and the percentage of α-SMA positive cells were assessed by flow cytometry. RT-PCR were also performed to examine the mRNA level of α-SMA. Upon the stimulation of different concentrations of rhCTGF, the expression of α-SMA were markedly stronger than that in negative controls. The percentages of α-SMA positive cells were significantly higher in the stimulated groups than that of negative controls (38.9 %, 65.5 % vs 2.4 %, P<0.01) .α-SMA mRNA levels were also up-regulated by the stimulation of rhCTGF (P<0.01). These results suggest that CTGF can promote the transdifferentiation of human renal tubular epithelial cells towards myofibroblast (Myo-F).

Effects of transforming growth factor β2 and connective tissue growth factor on induction of epithelial mesenchymal transition and extracellular matrix synthesis in human lens epithelial cells

AIM:To Investigate the effects of transforming growth factorβ2(TGF-β2)and connective tissue growth factor(CTGF)on transdifferentiation of human lens epithelial cells(HLECs)cultured in vitro and synthesis of extracellular matrix(ECM).METHODS:HLECs were treated with TGF-β2(0,0.5,1.0,5,10μg/L)and CTGF(0,15,30,60,100μg/L)for different times(0,24,48,72h)in vitro and the expression ofα-smooth muscle actin(α-SMA),the main component of the extracellular matrix typeⅠcollagen(Col-1)and fibronectin(Fn)were measured by using real-time polymerase chain reaction(PCR)and western-blot.RESULTS:TGF-β2 and CTGF significantly increased expression ofα-SMA mRNA and protein(P【0.05,P【0.001),Fn mRNA and protein(P【0.001),Col-1 mRNA and protein(P【0.001).TGF-β2 could induce HLECs expression of CTGF mRNA and protein in dosedependent manner(P【0.05,P【0.001).TGF-β2 and CTGF could induce HLECs to expressα-SMA,Fn and Col-1 in time-dependent manner.Each time of TGF-β2and CTGF induced HELCs expression ofα-SMA,Fn,Col-1 mRNA and protein was significant increase compared with control(P【0.05,P【0.001).CONCLUSION:TGF-β2 and CTGF could induce HLECs epithelial mesenchymal transition and ECM synthesis.

Activation of PPAR-γ Inhibits Differentiation of Rat Osteoblasts by Reducing Expression of Connective Tissue Growth Factor

Long-term treatment with an agonist of peroxisome proliferator-activated receptor （PPAR）-γ is associated with bone fractures in the clinical practice. However, the mechanisms underlying the frac- tures are not fully understood. This study was aimed to examine the effect of rosiglitazone （an agonist of PPAR-T） of different doses on the proliferation, differentiation, and transforming growth factor beta 1 （TGF-131）-induced expression of connective tissue growth factor （CTGF） in primary rat osteoblasts in vitro. Osteoblasts were isolated from newly born SD rats and treated with different doses of rosiglita- zone （0-20 gmol/L）. The proliferation and differentiation of osteoblasts were measured by MTT assay and NPP assay, respectively. The expression of CTGF was determined by RT-PCR and Western blotting. The results showed that most isolated osteoblasts displayed strong alkaline phosphatase （ALP） activity and treatment with different doses of rosiglitazone did not affect their proliferation, but significantly in- hibited the differentiation of osteoblasts in a dose-dependent manner. Moreover, treatment with different doses of rosiglitazone significantly reduced the TGF-131-induced CTGF mRNA transcription and protein expression in a dose-dependent manner in rat osteoblasts. It was concluded that the activation of PPAR-y may inhibit the differentiation of osteoblasts by reducing the TGF-131-induced CTGF expres- sion in vitro.

Connective tissue growth factor expression hints at aggressive nature of colorectal cancer

BACKGROUND Connective tissue growth factor(CTGF)is a mediator of transforming growth factor-beta signaling and plays a key role in connective tissue remodeling,inflammatory processes and fibrosis in various illnesses including cancer.AIM To investigate the role of CTGF in colorectal cancer(CRC)progression and to compare the CTGF expression with different clinicopathological parameters.METHODS Real-time polymerase chain reaction,immunohistochemistry and Western blotting was performed to evaluate the CTGF expression and the results were statistically analyzed against the clinicopathological variables of patient data using STATA software version 16.RESULTS CTGF expression levels in tumor specimens were significantly higher than their paired normal specimens.The higher protein expression levels showed a significant association with smoking,staging,tumor grade,invasion depth,necrosis of tumor tissue,and both lymphovascular and perineural invasion.As per the cox regression model and classification tree analysis,tumor-nodemetastasis stage and perineural invasion were important predictors for CTGF expression and prognosis of CRC patients.Survival analysis indicated that CTGF overexpression was associated with poorer overall and disease-free survival.CONCLUSION Expression of CTGF was increased in CRC and was linked with poor overall and disease-free survival of CRC patients.These findings support prior observations and thus CTGF may be a possible prognostic marker in CRC.

Expression of transcription factors Slug in the lens epithelial cells undergoing epithelial-mesenchymal transition induced by connective tissue growth factor

AIMTo investigate the expression of transcription factors Slug in human lens epithelial cells (HLECs) undergoing epithelial-mesenchymal transition (EMT) induced by connective tissue growth factor (CTGF).METHODSHLECs were treated with CTGF of different concentrations (20, 50 and 100 ng/mL) or without CTGF (control) for 24h. The morphological changes of HLECs were analysed by microscopy. The expression and cellular localization of Slug was evaluated by immumo-fluorescence. Expressions of Slug, E-cadherin and alpha smooth muscle actin (&#x003b1;-SMA) were further determined by Western blot analysis.RESULTSHLECs showed spidle fibrolasts-like characteristics and loosely connected each other after CTGF treatment. The immuno-fluorescence staining indicated that Slug was localized in the nuclei and its expression was induced by CTGF. The relative expressions of Slug protein were 1.64&#x000b1;0.11, 1.96 &#x000b1;0.03, 3.12 &#x000b1;0.10, and 4.08&#x000b1;0.14, respectively, in response to control group and treatment with CTGF of 20, 50 and 100 ng/mL (F=443.86, P&#x0003c;0.01). The increased Slug protein levels were correlated well with up-expression of &#x003b1;-SMA (0.78&#x000b1;0.05, 0.85&#x000b1;0.06, 2.17&#x000b1;0.15, 2.86&#x000b1;0.10; F=449.85, P&#x0003c;0.01) and down-expression of E-cadherin (2.50&#x000b1;0.11, 1.79&#x000b1;0.26, 1.05&#x000b1;0.14, 0.63&#x000b1;0.08; F=101.55, P&#x0003c;0.01).CONCLUSIONTranscription factor Slug may be involved in EMT of HLECs induced by CTGF in vitro.

Connective Tissue Growth Factor Expression in Rabbit Corneal Fibroblast and Its Effect on Fibroblast Proliferation In Vitro

The connective tissue growth factor (CTGF) expression in cultured corneal fibroblasts and its effect on corneal fibroblasts proliferation in vitro were examined. Total RNA was extracted from early passaged rabbit corneal fibroblasts by guanidine isothiocyanate one-step method and mRNA was reversely transcripted into complementary DNA (cDNA). Specific CTGF primers were used in the PCR reaction and the products were analyzed by electrophoresis to determine the expression of mRNA for CTGF against DNA marker. House-keeping gene GAPDH was used as control. Different concentrations of CTGF (0.5, 5, 50, 500, 5 000, 50 000 ng/ml) were added into the third passaged corneal fibroblast culture system, and its effect on corneal fibroblast proliferation was measured by MTT method. The results showed that compared with a GAPDH 450 bp band, CTGF RT-PCR product showed a specific 120 bp band as expected. CTGF produced a dose-dependent increase in the proliferation of corneal fibroblasts but it inhibited fibroblast proliferation at higher concentrations (5 000 and 50 000 ng/ml). It was concluded that proliferating corneal fibroblasts produce CTGF and CTGF helps to promote corneal fibroblast proliferation. The results indicated that CTGF might be involved in the corneal wound healing after photorefractive keratectomy in which corneal fibroblasts are activated to proliferate and secrete growth factors that in turn promote corneal fibroblast proliferation.