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.
ObjectiveTo illustrate the role of epidermal growth factor (EGF) secreted by astrocytes in the process of tacrolimus (FK506) in promoting neurite outgrowth.
MethodsThe spinal cord astrocytes and neuronal cells were isolated respectively from 2-day-old Sprague Dawley (SD) rats and 15-day SD pregnant rats, and cultured in vitro and identified by immunofluorescence staining. The spinal cord astrocytes were cultured with 20 μmol/L FK506 medium in the experimental group, and with FK506 free medium in the control group. The supernatant was collected after 24 hours for preparing conditioned medium, and astrocytes were collected. EGF proteins in the conditioned medium were detected with ELISA, and EGF gene expressions of astrocytes were detected with real-time quantitative PCR (RT-qPCR). The spinal cord neurons were cultured respectively with conditioned medium from the experimental group (FK506-CM) and the control group (C-CM) in group A and group B, also with neutralized C-CM and neutralized FK506-CM with anti-EGF neutralizing antibodies in group C and group D. Both the total neurite length and the longest neurite length were measured and compared among groups.
ResultsBoth astrocytes and neurons were confirmed by immunofluorescence staining. The EGF content of experimental group (0.241±0.044) was significantly higher than that of the control group (0.166±0.014) (t=3.93, P=0.01); EGF gene expression of the experimental group (1.12±0.25) was significantly higher than that of the control group (0.46±0.11) (t=5.78, P=0.00). The neurite length measurement displayed that the total neurite length and the longest neurite length of groups C and D were significantly shorter than those of groups A and B (P<0.05). Both the total and longest neurite length of group A were significantly longer than those of group B (P<0.05), but no significant difference was shown between groups C and D (P>0.05).
ConclusionThe EGF secreted by spinal cord astrocytes can promote the neurite outgrowth. So spinal cord astrocytes can be used as an important intermediary target of FK506 to promote the recovery of neurological function.
OBJECTIVE This paper aims to explore the new method of continuous delivery of epidermal growth factor to wounds by transfected fibroblasts to promote wound repair. METHODS It was constructed a novel chimeric expression plasmid in which the biologically active portion of the human epidermal growth factor (EGF) gene was fused in-frame to the human granulocyte colony-stimulating factor signal sequence. RESULTS Clonally selected human fibroblasts transfected with this construct could secrete biologically active EGF. After the transplantation of irradiated gene-transfected fibroblasts suspended in fibrin glue to murine full-thickness wounds, EGF could be demonstrated for at least seven days in the wounds, slowly decreasing from initially 470 ng/L to 140 ng/L in 7 days. No EGF was found in the wound at 14 days. CONCLUSION A single application of irradiated EGF gene transfected fibroblasts to wounds can continuously deliver the transgene in vivo and can be used to administer drugs to the wound bed during the crucial first seven days of wound-healing.
【 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.
ObjectiveTo detect expressions of epidermal growth factor receptor (EGFR), BRAF, and K-Ras genes in colorectal carcinoma tissues and explore pathogenesis in colorectal carcinoma.
MethodThe expressions of EGFR, BRAF, and K-Ras genes were detected in these 136 colorectal carcinoma tissues and their corresponding adjacent normal colorectal tissues by immunohistochemistry.
ResultsThe expressions of EGFR and BRAF in the colorectal carcinoma tissues were significantly higher than those in their corresponding adjacent normal colorectal tissues (P<0.05), but the expression of K-Ras had no significant difference between these two tissues (P>0.05). The expression of EGFR gene was related to the TNM stage, lymphatic metastasis, or degree of differentiation. The expression of BRAF gene was related to the TNM stage. The expression of K-Ras gene wasn,t related to the TNM stage, lymphatic metastasis, or degree of differentiation. The correlation analysis results showed that there was no relation among the EGFR, K-Ras, or BRAF expression.
ConclusionsUp-regulated of EGFR and BRAF gene expressions might be related to development of colorectal carcinoma, and role of K-Ras is unclear. Anti EGFR and BRAF target therapy might be benefited for patients with colorectal carcinoma.
Objective To investigate the effect of topical external administration of recombinant human epidermal growth factor (rhEGF) when controll ing blood sugar on expression of epidermal growth factor receptor (EGFR) and EGFR mRNA of wound in diabetes mell itus (DM) combined with scald. Methods A total of 136 male Wistar rats weighing (188.57 ± 6.59) g were randamly divided into 4 groups (groups A, B, C, and D, n=34). The rats was made DM model by intraperitoneal injected 60 mg/kg streptozocin in groups A, B, and C; rats were injected buffer alone in group D as control group. After 8 weeks, the rats of 4 groups were placed in 80℃ hot water for 6 seconds for preparation of the back deep II degree scald model. In group A, the blood sugar level was controlled at the level of group D 1 week before scald model; within 24 hours after models preparation, rhEGF was sprayed on wound at 150 U/cm2 . In group B, the rats were given the same treatment as group A except not controll ing blood sugar. In group C, the blood sugar was controlled as group A and wound was suture fixation with 1% silver sulfadiazine cream at 24 hours after the model. In group D, the same treatment as group A was given after injury. The heal ing rate of the wound was detected at 3, 7, 11, 15, and 21 days after injury; the EGFR mRNA expression was determined by mRNA hybridization in situ, and the EGFR protein expression was deterimined by immunohistochemistry and Western blot at 1, 3, 5, 7, 11, 15, and 21 days. Results? All the rats survived at the end of experiment. There was no significant difference in the heal ing rate of the wound among the 4 groups at 3 days (P gt; 0.05). The heal ing rate of the wound was significantly higher in groups A and D than in groups B and C (P lt; 0.05) at 7, 11, 15, and 21 days. The expession of EGFR mRNA in 4 groups was observed by hybridization in situ, which mainly distributed in the dermal fibroblasts, capillary endothel ial cells and remnants of skin and wound edge epithel ium of the subsidiary; the expessions reached the peak at 5 days in group A, at 7 days in groups B and C, and at 11 days in group D; and the peak level was significantly higher in groups A and D than in groups B and C (P lt; 0.05). Immunohistochemistry and Western blot showed that the expession of EGFR protein was observed in 4 groups and reached the peak level at 7 days in groups A and B, and at 11 days in groups C and D; showing significant difference between groups B, C and groups A, D (P lt; 0.05). Conclusion External appl ication of rhEGF when controll ing blood sugar can accelerate obviously the wound heal ing in DM combined with scald. After controll ing blood sugar, external appl ication of rhEGF can boost obviously the expressions of EGFR mRNA, EGFR, and the extending process of signal conduction.
Objective To investigate the roles of NF-κB and EGFR in hepatolithiasis associated with intrahepatic cholangiocarcinoma. Methods Ninety cases of liver tissue specimens from hepatectomies performed in the 2nd Affiliated Hospital of Sun Yat-sen University between August 1989 and June 2009 were enrolled in the study. Among them, 33 cases of hepatolithiasis associated with intrahepatic cholangiocarcinoma were considered as observing group, 32 cases of hepatolithiasis as control group, and 25 cases of normal bile duct tissues as normal control group. The SP method of immunohistochemical staining was applied to detect the expressions of NF-κB and EGFR in intrahepatic biliary ducts epithelial cells, and their relations with clinicopathologic factors and the accumulated survival rate of hepatolithiasis associated with intrahepatic cholangiocarcinoma were analyzed. Results Expression rates of NF-κB and EGFR were gradually raised from normal control group, control group to observing group (Plt;0.01). Expression of EGFR in tumor patients was related to histopathologic differentiation grading and the depth of tumor invasion (Plt;0.05), but not to gender, age, or lymph node metastasis (Pgt;0.05)； there were no significant relationships between the expression of NF-κB and factors described above (Pgt;0.05). The survival rate of patients with tumor expressed EGFR was significantly lower than that of patients with tumor non-expressed EGFR (Plt;0.01). Conclusions NF-κB expression is in the early stage during intrahepatic cholangiocarcinoma genesis. NF-κB and EGFR play cooperating roles during hepatolithiasis carcinogenesis process. Over expression of EGFR is related with poor differentiation and prognosis of tumor.
Objective
To assess the efficacy of a kind of new material lipid magnetic particle for isolation and detection of lung cancer circulating tumor cells (CTCs).
Methods
Immune lipid magnetic particles were prepared with reverse evaporation method and they were assembled into kits with EpCAM and EGFR antibody respectively. Their efficacy were evaluated by detecting A549 cells in group A (A549 cells mixed in phosphated buffer solution) and group B (A549 cells mixed in blood from healthy volunteers). Lung cancer CTCs of hospitalized patients were also detected with both immune magnetic particals. Then the detecting efficacy was compared between EpCAM immune lipid magnetic particles and the conventional CellsearchTM system.
Results
The immune lipid magnetic particles had high capture efficiency for CTCs isolation and identification. The median of EpCAM immune lipid magnetic particles method in detecting A549 cells in group A was 92%, and EGFR was 90%. The median of EpCAM immune lipid magnetic particles method in detecting A549 cells in group B was 85%, and EGFR was 81%. In 13 patients with lung cancer, CTCs can be detected with both immune lipid magnetic particles methods and both medians were 5; In negative control, the medians of both methods were 0 (P＜0.05). EpCAM immune lipid magnetic particles method can detect more CTCs than conventional CellsearchTM system in 3 lung cancer patients.
Conclusions
Immune lipid magnetic particles have good efficacy for lung cancer CTCs detection and has promising clinical application value. The EpCAM immune lipid magnetic particles have equal efficiency in detecting lung cancer CTCs with EGFR. There is a trend that EpCAM immune lipid magnetic particles is superior to the conventional CellsearchTM system.
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 effect of the traditional Chinese medicine “Tetrandrine”(TET) and its significance on epidermal growth factor(EGF) and its receptor(EGFR) in the lung of nitrofen-induced congenital diaphragmatic hernia(CDH) rat model. Methods Twenty female rats were given maternal administration of a single oral dose (115 mg/rat) of nitrofen to induce CDH at 9.5 days after pregnancy and were dividedinto normal solution group(NS, n=5), dexamethasone group (Dex, n=5),tetrandrine group (TET, n=5) and Dex+TET group(n=5) at 18.5 days; 4 rats were given edible oil as controls. All fetuses were delivered by cesarean section at 21.5 days. Lung histologic evaluations and EGF, EGFR immunohistochemical staining and image analysis were performed. Results CDH was observed in 64 of the 137 rat fetuses (46.7%) in the experimental groups; no CHD was observed in 36 rat fetuses of control group. The lungs of CDH fetuses showed marked hypoplasia in NS group, in contrast to improved mesenchymal differentiationin that of Dex, TET, Dex+TET groups. The expression of EGF was weaker and weaker and that of EGFR was ber and ber as following order: NS, TET, DEX, T+D and control groups; showing significant differences between them (Plt;0.05). Conclusion Prenatal TET administration shows marked improvement in pulmonary hypoplasia through preregulating crest-time of EGF expression and upregulating EGFR expression in the lungs of nitrofen-induced CDH rat model. A combination of TET and Dex would generate evident synergistic effect.
