Objective:To study the effects of growth factor on the proliferation of the cultured huamn retinal glial cells. Methods:EGF(0.5～100.0ng/ml) and NGF (0.5～10.0ng/ml) were added to cultures of human retinal glial cells and the proliferation rates of the cells were measured by MTT method. Results:EGF at a dosage ranging from 0.5ng/ml to 100.0ng/ml and NGF (0.05～10.0ng/ml) stimulated the cellular proliferation effectively with their EC 50 of 17ng/ml and 0.7 ng/ml respectively. Conclusion:Both EGF and NGF NGF had an effective stimulation on human retinal glial cell proliferation.They may play a role in the formation of PVR. (Chin J Ocul Fundus Dis,1998,14:33-34)
【 Abstract 】 Objective Overexpressions of epidermal growth factor (EGF) and EGF receptor have been associated with progression and invasive phenotype of pancreatic cancer. However, the underlying molecular mechanism by which EGF worked in pancreatic cancer cells has not been completely understood. In this study, effect of EGF on the invasion and metastasis of pancreatic cancer cells and its regulatory mechanism were investigated. Methods The effects of EGF on the proliferation, adhesion and invasion of pancreatic cancer cells were detected by WST-1 proliferation assay, adhesion assay and invasive assay, respectively. The activity and expression of MMP-2 and MMP-9 were examined by zymography, Western blot and RT-PCR, respectively. The activity of NF- κ B was examined by EMSA. Results EGF could significantly promote the invasiveness of pancreatic cancer cells but did not affect cell proliferation or adhesion. The expressions of NF- κ B and MMP-9 were significantly increased by EGF, but EGF did not affect the activity and expression of MMP-2. Furthermore, EGF stimulated the NF- κ B binding activity. Pretreatment with NF- κ B inhibitors, pyrrolidine dithiocarbamate (PDTC), could significantly inhibit the activity of NF- κ B induced by EGF. Meanwhile, the EGF-induced expression and activity of MMP-9, as well as cell invasiveness were also inhibited by NF- κ B inhibitor. Conclusion EGF could increase the expression and promote the invasiveness of MMP-9 via the activation of NF- κ B in pancreatic cancer cells, which implies that NF- κ B inhibitant, such as PDTC, may diminish the invasiveness of pancreatic cancer cells.
Objective To investigate the activation and role of signal transduction pathway of epidermal growth factor (EGF)-epidermal growth factor receptor (EGFR)-mitogen activated protein kinase (MAPK) in proliferation of human retinal pigment epithelial (RPE) cells. Methods Human RPE cells were stimulated with 0.1%，10% foetal calfserum (FCS) and EGF(0.1, 1, 10, 50 and 100 ng/ml)in 0.1% FCS Dulbeco′s modified Eagle′s medium (DMEM) and in 10% FCS DMEM for 3 days, respectively. Immunohistochemical staining and in situ hybridization were used to observe the expressions of EGFR protein and EGFR mRNA，respectively. Activation of MAPK was detected by immunohistochemical method with specific anti-phosphorylated ERK 1/2 antibody. Results The optimal concentrations of EGF were 10 ng/ml in 0.1% FCS DMEM and 1 ng/ml in 10% FCS DMEM. After 3 days of stimulation with EGF, phosphorylated ERK 1/2 staining was detectable in nucleus of RPE cells, whereas cells presented immunostaining for phosphorylated ERK 1/2 in the cytoplasm before stimulation. Conclusions EGF may improve the expression of EGFR protein and EGFR mRNA of RPE cells, and induced MAPK nuclear translocation in a concentration-dependent manner. EGF-EGFR-MAPK signal transduction pathway may play a key role in RPE cells proliferation, and serum exerts an important acceclerating function in the process. (Chin J Ocul Fundus Dis，2004，20：67-132)
Objective To evaluate the effects of two different epidermal growth factor receptor tyrosine kinase inhibitors ( EGFR-TKIs) , Gefitinib and Erlotinib, on lung fibrosis induced by bleomycin.Methods Forty BALB/c female mice were randomly divided into four groups, ie. a control group( saline given orally and intratracheally) , a fibrosis group( saline given orally with bleomycin instillation) , a Gefitnib group( Gefitnib 20 mg/kg given orally with bleomycin instillation) , and an Erlotinib group ( Erlotinib25 mg/kg given orally with bleomycin instillation) . Bleomycin ( 3 mg/kg) was intratracheally instilled on the first day. Gefitinib or Erlotinib was given orally daily and normal saline as control. Then they were sacrificed by abdominal aortic bleeding 14 days after the bleomycin instillation. The left lung was stained with HE and Masson’s trichrome staining respectively for pathological examination. Total EGFR and phosphorylated EGFR were detected by immunohistochemistry. Hydroxyproline ( HYP) assay was performed in the right lung.Results Both Gefitinib and Erlotinib significantly reduced lung collagen accumulation and the content of HYP. Immunohistochemistry revealed that phosphorylation of EGFR in lung mesenchymal cells induced by bleomycin was inhibited. Furthermore, there was no difference between Gefitinib and Erlotinib in inhibiting lung fibrosis. Conclusion Our findings suggest that, in the preclinical setting, EGFR-TKIs may have aprotective effect on lung fibrosis induced by bleomycin.
PURPOSE:To measure the epidermal growth factor (EGF)contents in vitreous and serum samples in normal subjects and patients with proliferative retinal diseases. METHODS: Using radioreceptor assay(RRA)to measure the EGF contents in vitreous and serum in patients with proliferative diabetic retinopathy (PDR) 16 cases, proliferative vitreoretinopathy (PVR) 20 cases, central retinal vein occlusion (CRVO)16 cases,other retinal vascular diseases 5 cases,and controls 10 cases. RESULTS:The EGF levels in vitreous of the patient group were apparently higher than those of the controls (Plt;0. 001). Among patient group,the EGF contents in vitrectomy fluid was lower than that of original vitreous, reflecting about 60~ 63~ EGF level in original vitreous, Both showed positive correlation. To compare the EGF contents in serum of patients and controls,the EGF contents in serum of PDR group increased significantly. In CRVO group the EGF contents also increased,while in PVR group,the EGF contents were lower than those of the controls. CONCLUSIONS: The increased EGF contents in vitreous of patient group may play a role in the pathogenesis of proliferative retinal diseases. The RRA is a sensitive method for quantitative measurement of growth factor. （Chin J Ocul Fundus Dis,1996,12: 91- 93）
OBJECTIVE: To explore the expressive characteristics of epidermal growth factor (EGF) and its receptor (EGFR) in tissues of fetal and adult intestines. METHODS: The expression intensity and distribution of EGF and EGFR were detected with pathological and immunohistochemical methods in 6 specimens of adult (16-54 years) intestines and 18 specimens of fetal intestines with different gestational ages (13-31 weeks). RESULTS: Positive protein particles of EGF and EGFR could be detected in tissues of fetal and adult intestines. The protein expressions of EGF and EGFR were elevated progressively with the gestational age. EGF was mainly located in the cytoplasm and extracellular matrix of intestinal villus cells, endothelial cells and tunica serosa epithelial cells, while EGFR chiefly distributed in the cellular membrane of these cells. CONCLUSION: The endogenous EGF and EGFR might be involved in the intestinal development at embryonic stage, in the structural and functional maintenance at adult stage, and in the wound healing after injury.
Objective To investigate the effect of Fujiguning Ointment and epidermal growth factor (EGF) on the wounds with bone exposed. Methods Forty-five rabbits were made the models of a 2 cm×5 cm wound on theback with exposure of 4 spinl process and vertebral lamina of thoracic vertebrae, and divided into 3 groupsaccording to different methods of therapy: Group A(Fujiguning OintmentEGF), Group B(Fujiguning Ointment) and Group C(normal saline). During experimental period of 60 days, the healing of wounds was observed and immunohistochemistry and in situ hybridization were employed to detect the expression of EGF/EGFR and EGF/EGFRmRNA in the granulation tissues. From February 2002 to May 2003, 23 cases of wounds with bone exposure werelocally treated with Fujiguning Ointment and EGF. First, Fujiguning Ointmentwas used to cover the wounds. After the granulation grew and covered the exposed bone, EGF was used to infiltrate the wound until the wound healed. Results The healing time of wounds with bone exposure was shorterin group A(30 days) than those in group B (45 dyas) and group C (60 dyas), showing statistically significant difference (Plt;0.01). EGF/EGFR increased significantly, the expression of EGF and EGF mRNA reached the peak at the 15th day, the expression of EGFR and EGFR mRNA reached the peak during the 15th and the 22nd days in the Fujiguning OintmentEGF group and Fujiguning Ointment group in comparison with normal saline group. Twentythree cases of wounds were cured and the average healing time was 51 days. Conclusion Fujiguning Ointment and EGF can promote the healing of the wounds with bone exposure.
Porpose To investigate the optimal concentration of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on DNA synthesis and their synergism indensity arrested human retinal pigment epithelial (RPE) cells. Methods Growth factor effects in cultured human RPE of the 6th generation were assessed by [3 H]-thymidine incorporation and radioautography. Results EGF and bFGF were potent stimulators when used alone,and their optimal concentrations were 10ng/ml in DMEM and 1ng/ml in 2% serum DMEM.When used in combination (10ng/ml EGF and 10ng/ml bFGF),they caused a significant enhancement of [3 H]-thymidine incorporation about 2.96 times. Conclusion EGF and bFGF were potent stimulators in RPE cells,and demonstrated synergism in their action. (Chin J Ocul Fundus Dis,1998,14:98-100)
OBJECTIVE: To investigate the mechanism of overhealing alleviation by salvia miltiorrhiza (SM) in wound healing. METHODS: Fibroblasts were cultured in vitro, and SM was applied with different concentrations (40, 80, 160 and 320 micrograms/ml) and time(the 1st, 2nd, 3rd, 4th and 5th days) to influence their autocrine. The levels of transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF) were determined by ELIAS and radioimmunoassay respectively. RESULTS: The SM could inhibit autocrine of TGF-β1 by fibroblasts (P lt; 0.05). However, it did not affect autocrine of EGF (P gt; 0.05). CONCLUSION: The above results indicate that SM reduces overhealing by inhibiting the autocrine of TGF-β1 selectively.
Abstract For the purpose of studying the effects on wound healing of three new bioelectret composites (BC) which are composed ofcollagen polyvinyl alcohol and epidermal growth factor (EGF), 30 rabbits were divided into 5 groups. Three wounds in round shape (1.8 cm in diameter) were made in each side of the back of the rabbits. The wounds of 1～3 groups were treated by one of the three BC respectively, group 4 treated by SDAg, and group 5 were treated by Normal saline as control. From observation of the growth of the granulation tissue, the reepithelization and the pathological assessment, it was shown that the quality of wound healing in all BC treated wounds was better than that in SDAg or the control. It indicated that the BC benefited the wound healing, and this might also be due to its bioelectric effects and the direct effects from growth factor.