Objective To investigate the effect of nerve growth factor(NGF) on inducing directional migration of neural stem cells in vitro. Methods Semi-solid cell culture method was used to observe the cell′s directional migration;immunocytochemical method was used to analyse the neuronal phenotype. Results In the semi-solid medium with gradient concentration of NGF,neural stem cells migrated directionally from lower concentration of NGF to higher concentration,and the nearer to the source of NGF,the more evident the result.The migrated cells show neuron charcteristics.In the medium with NGF but with no gradient concentration,the cells migrated without direction.Conclusion NGF could induce directional migration of neural stem cells.

ObjectiveTo investigate hepatocyte growth factor (HGF) levels in the tissue and serum of patients with chronic hepatitis,cirrhosis or hepatocellular carcinoma (HCC),and analyze the clinical significances of HGF for HCC.MethodSurgical specimens from 97 patients were collected during Dec.2003 to Aug.2008 in the Third Central Hospital.The patients were prospectively enrolled and categorized into four groups:normal subjects ( n =11 ),chronic hepatitis B or C ( n =6＝,cirrhosis ( n =20)and HCC ( n =60 ) including well-differentiated ( n =21 ),moderately differentiated ( n =23 ),poorly differentiated (n =16) specimens.N0 (n =24),N1 (n =21 ),N2 (n =54) and N3 (n =43) were tissues respectively removed from liver at 0,1,2 or 3 cm beyond the margin of tumor.HGF mRNA expression in liver tissues was determined by real-time quantitative reverse transcription- (RT)-PCR.Serum HGF levels in the other cases of normal subjects ( n =20),chronic hepatitis B or C ( n =20),cirrhosis ( n =20) and HCC (n =57) were measured by ELISA.The Kaplan-Meier method with log-rank test was employed for survival analysis.Univariate and multivariate analyses were performed to identify prognostic factors in each group.ResultsThe HGF mRNA in normal subjects,chronic hepatitis,cirrhosis,N3,N2,N1,N0 and HCC were0.99(0.78-1.66),2.15(1.06-3.40),1.78(1.18-2.73),4.59(2.67 -8.63),3.86 ( 2.25 - 6.45 ),3.12 ( 1.59 - 5.74 ),2.92 ( 0.88 - 5.99 ) and 0.48 ( 0.19 - 1.06 ) respectively.The serum concentration of HGF in the normal subjects,chronic hepatitis,cirrhosis and HCC patients were (0.31 ± 0.05 ),(0.65 ± 0.07 ),( 1.27 ± 0.30 ) and ( 2.06 ± 0.66) μg/L respectively.The highest level of HGF mRNA was found in N3,while the HGF mRNA expression in HCC was [ (2.14 ± 0.52 ) μg/L] lower than that not only in the non-tumor tissues,but also in the normal control ( U =196.50,P =0.03 ).The serum concentration of HGF was significantly higher in patients with chronic hepatitis,cirrhosis or HCC than in normal subjects.The serum HGF level of HCC was bounced after hepatectomy (t =2.70,P ＜0.01 ).On the logistic regression analysis,the tumor numbers and Child-pugh were related with the levels of the tissue HGF mRNA and serum HGF of HCC,OR were0.15 (95％CI:0.03-0.72,P＜0.05) and0.13 (95％CI:0.27 -0.89,P ＜0.05 ),respectively.Univariate analysis using the Cox proportional hazards model in the complication groups revealed that the levels of the tissue HGF mRNA and serum HGF were significant risk factors of death for HCC,OR were 0.02 (95％ CI:0.00 - 0.52,P ＜ 0.05 ) and 10.01 (95％ CI:1.16 -86.23,P ＜ 0.05 ),respectively.On the Log-rank analysis,no statistically difference in the cumulative survival was found between the two groups categorized by median (0.49) of tissue HGF mRNA 2 - AACT (X2 =0.13,P =0.72).While the HCC patients were dichotomized by their the median(0.69 μg/L) of serum HGF concentration,the death risk for the patients with higher levels of HGF was increased 2.84 fold than those with lower levels (95％ CI:1.03 - 7.92,P ＜ 0.05 ).ConclusionHGF mRNA expression is decreased in tumor tissues,while its level in tumor adjacent live and serum is significantly elevated and is in association with shortened postoperative survival of HCC patients.