BACKGROUNDMyopia is a common disorder and the incidence has increased yearly, but its pathogenesis remains unclear. The aim of this study was to investigate the possible role of hepatocyte growth factor (HGF) and its receptor c-Met in the development of lens-induced myopia in guinea pigs.

METHODSSixty one-week-old guinea pigs were chosen. The right eyes were treated with -10.0 diopters (D) lenses as the lens-induced myopia group; the left eyes remained untreated as the control group. Six weeks later, refractive status and axial length were determined by streak retinoscopy and A-scan ultrasonography, respectively. The guinea pigs were killed and both eyes collected. Morphological changes were observed by hematoxylin and eosin staining. The expression levels of HGF, c-Met, and matrix metalloproteinase 2 (MMP-2) mRNA and protein in the posterior sclera were analyzed by RT-PCR and Western blotting, respectively.

RESULTSThe lens-induced myopia group became myopic with a significant increase in axial length and a significant decrease in refraction. Compared with the control group, the posterior retina and sclera were thinner in the lens-induced myopia group. The expression levels of HGF and MMP-2 mRNA and protein and of phosphorylated c-Met protein were significantly higher in the posterior sclera of the lens-induced myopia group than in the control group (all P < 0.05). In the lens-induced myopia group, the expression level of MMP-2 in the posterior sclera positively correlated with the expression level of HGF (r = 0.902, P < 0.05) and phosphorylated c-Met (r = 0.885, P < 0.05).

CONCLUSIONHGF/c-Met might play a role in the development of lens-induced myopia in guinea pigs by upregulating the expression of MMP-2.

Animals ; Guinea Pigs ; Hepatocyte Growth Factor ; metabolism ; Myopia ; etiology ; metabolism ; Proto-Oncogene Proteins c-met ; metabolism

Humans ; Proto-Oncogene Proteins c-met ; genetics ; metabolism ; Stomach Neoplasms ; genetics ; metabolism

Animals ; Hepatocyte Growth Factor ; metabolism ; Humans ; Proto-Oncogene Proteins c-met ; Serine Endopeptidases

This research aims to construct a lentiviral expression vector carrying the extracelluar domain (ED) of human hepatocyte growth factor receptor (C-Met), and to express it in transfected 293T cells. The extracellular domain of C-Met was amplified by RT-PCR, ligated with lentiviral expression vector p RRL-CMV-ED, and then expressed in 293T cell line. The expressed protein was purified and identified by RT-PCR and Western blot. The enzyme digestion and sequence analysis showed that the lentiviral expression vector p RRL-CMV-ED was constructed correctly. The size of amplified genes was about 2 700 bp. The purified protein with Ni-affinity column was about 105 kD analyzed by SDS-PAGE. The Western blot and ELISA results showed that the expressed protein which could bind to HGF specifically was the extracelluar domain of human hepatocyte growth factor receptor. This research may lay a foundation for further study of anti-C-MET monoclonal antibody and neutralizing antibody.
Genetic Vectors ; HEK293 Cells ; Humans ; Lentivirus ; Proto-Oncogene Proteins c-met ; genetics ; metabolism ; Transfection

OBJECTIVETo study the effects of lipid rafts on cell signal transmembrane transduction mediated by c-Met.

METHODSAfter HepG2Cells were treated with MbCD to disrupt the lipid rafts and were treated with artificial recombination hepatocyte growth factor to activate c-Met, the activities of PLCr1/PKC, PI3K/Akt and MAPK signaling pathways in HepG2 cells were analyzed using Western blot.

RESULTS(1) After disruption of lipid rafts with MbCD, phosphorylation of PLCr1 decreased by 35% (P = 0.022); the content of PLCr in the cytoplasm increased by 1.75 fold (P = 0.017); PLCr1 conjugated with membrane decreased by 30% (P = 0.037). (2) The content of PKB in the cytosol decreased by 38% (P = 0.028), and the phosphorylation level of PKB conjugated with membrane decreased by 14% (P = 0.041). At the same time, PDK translocation from cytosol to the plasma membrane and its activation were inhibited by treatment with MbCD. (3) Treatment with MbCD had no significant effect on ErK/MAPK, p38/MAPK and JNK/MAPK signaling pathways.

CONCLUSIONDisruption of lipid rafts with MbCD inhibits the activation of PLCr1/PKC and PI3K/PKB signaling pathways by HGF/cMet, but has no effect on MAPK signaling pathway.

Hep G2 Cells ; Humans ; Membrane Microdomains ; metabolism ; Mitogen-Activated Protein Kinases ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Phospholipase C gamma ; metabolism ; Phosphorylation ; Proto-Oncogene Proteins c-akt ; metabolism ; Proto-Oncogene Proteins c-met ; metabolism ; Signal Transduction

Objective To investigate the expressions of CD44,CD47,and c-met in ovarian clear cell carcinoma (OCCC) tissue and their correlations with clinical variables and prognosis. Methods Immunohistochemical method was used to investigate the expressions of CD44,CD47,and c-met in tissues from 86 OCCC patients and the relationships of their expressions with the clinicopathological factors of OCCC were analyzed. Results The expressions of CD44,CD47,and c-met were significantly high in OCCC tissues (90.7%,91.9%,and 94.2%,respectively). The strong positive expressions of CD44 and CD47 were significantly correlated with advanced International Federation of Gynecology and Obstetrics stages,chemotherapeutic resistance,and poor prognosis (all P<0.05),the strong positive expression of c-met was significantly correlated with chemotherapeutic resistance and poor prognosis (all P<0.05),whereas there was no correlation between the strong positive expressions of CD44,CD47,and c-met and the lymphatic node metastasis. COX survival analysis revealed that advanced International Federation of Gynecology and Obstetrics stages and high expressions of CD44,CD47 and c-met were independent risk factors for poor prognosis (P<0.05). There was a positive correlation between CD44 (or CD47) and c-met and between CD44 and CD47 (the Spearman correlation coefficient rwas 0.783,0.776,and 0.835,respectively,all P<0.01). Conclusions The expressions of CD44,CD47,and c-met increase in OCCC tissues and are correlated with each other. High expressions of CD44,CD47,and c-met are independent factors for poor prognosis.
Adenocarcinoma, Clear Cell ; metabolism ; CD47 Antigen ; metabolism ; Female ; Humans ; Hyaluronan Receptors ; metabolism ; Lymphatic Metastasis ; Ovarian Neoplasms ; metabolism ; Prognosis ; Proto-Oncogene Proteins c-met ; metabolism ; Survival Analysis

Adolescent ; Child ; Child, Preschool ; Female ; Hepatocyte Growth Factor ; metabolism ; Humans ; Kidney ; metabolism ; pathology ; Male ; Nephrotic Syndrome ; metabolism ; pathology ; Proto-Oncogene Proteins c-met ; metabolism

OBJECTIVETo investigate the role of expression of hepatocyte growth factor (HGF) and its receptor (c-Met) in gastric cancer.

METHODSThe expression of HGF and c-Met was detected with SABC immunohistochemistry in 44 specimens of gastric cancer, 20 chronic superficial gastritis, 10 chronic atrophic gastritis and 16 gastric ulcer tissues.

RESULTSNo positive expression of HGF/c-Met was found in the chronic superficial gastritis specimens. The positivity rates of HGF in the gastric cancer was 72.7% (32/44), significantly higher than that in chronic atrophic gastritis [20% (2/10), P<0.005] and gastric ulcer [37.5% (6/16). P<0.025]. The positivity rates of c-Met in gastric cancer [77.3% (34/44)] was also significantly higher than that in chronic atrophic gastritis [40% (4/10), P<0.05] and gastric ulcer [37.5% (6/16), P<0.025].

CONCLUSIONCo-expression of HGF and c-Met in gastric cancer may promote the progression of the malignancy, and also opens a new pathway for the therapy of gastric cancer.

Adult ; Aged ; Female ; Hepatocyte Growth Factor ; metabolism ; Humans ; Male ; Middle Aged ; Proto-Oncogene Proteins c-met ; metabolism ; Stomach Neoplasms ; metabolism ; pathology ; Young Adult

OBJECTIVETo investigate the association between expression of hepatocyte growth factor(HGF) and its receptor c-Met and primary colorectal cancers with synchronous liver metastases.

METHODSA total of 30 colorectal cancer patients with synchronous liver metastasis underwent radical resection of primary cancer and liver cancer in our hospital from June 2001 to June 2010. According to lymphatic metastasis, patients were divided into group A(T1~T4N1~N2M1, n=21) and group B(T1~T4N0M1, n=9). Twenty-one matched T1~T4N1~N2M0 and 21 T1~T4N0M0 patients were used as the controls of group A. Nine matched T1~T4N0M0 patients were used as the controls of group B. Expressions of HGF and c-Met in tissues of primary loci, liver loci and metastatic loci were detected by immunohistochemistry.

RESULTSIn primary loci of group A, the positive rate of HGF was significantly higher than that of T1~T4N1~N2M0 and T1~T4N0M0 controls [71%(15/21) vs. 43%(9/21), 19%(4/21), all P<0.05]. The positive rate of c-MET[90%(19/21)] was significantly higher compared to T1~T4N0M0 control[43%(9/21), P<0.05], while not significantly different compared to T1~T4N1~N2M0 control[86%(18/21)]. In primary loci of group B, positive rates of HGF and c-MET were not significantly different as compared to T1~T4N0M0 control[6/9 vs. 5/9, P>0.05; 8/9 vs. 6/9, P>0.05]. Concordance of HGF and c-MET expression in group A among primary loci, lymphatic metastatic loci and hepatic metastatic loci was 81%(17/21) and 76%(16/21).

CONCLUSIONHGF-c-Met may play a role in colorectal cancer patients with synchronous liver metastasis who have regional lymphatic metastasis, and may have few effect on colorectal cancer with synchronous liver metastasis without corresponding lymphatic metastasis.

Adult ; Aged ; Colorectal Neoplasms ; metabolism ; pathology ; Female ; Hepatocyte Growth Factor ; metabolism ; Humans ; Liver Neoplasms ; secondary ; Lymphatic Metastasis ; Male ; Middle Aged ; Proto-Oncogene Proteins c-met ; metabolism

OBJECTIVETo explore the effect of c-met ribozyme transfection on biological behavior of gastric carcinoma cells.

METHODSU1/met292 plasmid containing c-met ribozyme gene was transfected into L2 subline of SGC-7901 gastric cell line, and the proliferative ability, distribution of cell cycle, protein expression of VEGF and c-met, as well as the potential of liver metastasis of the transfected subline were determined.

RESULTSThere were no significant difference in proliferative ability, distribution of cell cycle between the transfected cells and the control cells. The protein expression of VEGF and c-met, as well as the liver metastatic potential significantly decreased in the transfected cells than those in the control cells (P< 0.05).

CONCLUSIONThe liver metastatic potential of c-met positive gastric cancer cells may be prevented by inhibiting c-met expression.

Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Plasmids ; Proto-Oncogene Proteins c-met ; genetics ; Stomach Neoplasms ; genetics ; metabolism ; pathology ; Transfection ; Vascular Endothelial Growth Factor A ; metabolism