Objective To observe the expression of p53, bcl-2 genes, vascular endothelial cell growth factor(VEGF), basic fibroblast growth factor(bFGF), insulin-like growth factor-I (IGF-I), and the receptors of these factors of retinal vascular endothelial cells (VECs) of 1- to 20-week diabetic rats, and the relationship between the expressions and cell cycle arrest.Methods Retinal sections of diabetic rats induced by alloxan were immunohistochemically stained and observed by light microscopy (LM) and electron microscopy (EM). Dot blotting and Western blotting were used to determine the expression of mRNA, proteins of p53 and bcl-2. Results Under LM, immunohistochemical positive expression of p53 and bcl-2 were found on the vessels of ganglion cell layer and inner nuclear layer of retinae of 8- to 20-week diabetic rats; under EM, these substances were observed depositing in VECs. The retinal VECs also expressed VEGF, bFGF, IGF-I and their receptors. There was no positive expression of other cell types in these retinae, all cell types of retinae in control group, or all cells of retinae of diabetic rats with the course of disease of 1 to 6 weeks. The result of dot blotting revealed that retinal tissue of 20-week diabetic rat expressed p53 and bcl-2 mRNA, and the result of Western blotting revealed that they also expressed p53 and bcl-2 proteins. But retinal tissues of control group did not. Positive expression of bax was not found in the retinae in control group or 1- to 20-week diabetic rats. Conclusion p53, bcl-2 may introduce cell cycle arrest of VECs of retinae in 8- to 20-week diabetic rats. High glucose might stimulate the expression of VEGF, bFGF, IGF-I and their receptors, and the growth factors may keep VECs surviving by self-secretion. (Chin J Ocul Fundus Dis,2003,19:29-33)
Objective To detect the expression of thromhospondin-1 (TSP-1) in gastric cancer and metastaticlymph node tissues, and to study its relationship of TSP-1 to clinicopathologic parameters or tumor angiogenesis. Methods The TSP-1 and vascular endothelial growth factor (VEGF) expressions and microvessel density (MVD) were evaluated by immunohistochemistry in 72 specimens obtained by gastric resection from patients with gastric cancer, including corres-ponding adjacent normal gastric mucosa tissues (distant from cancer ≥5 cm) and lymph nodes surrounding cancer. A semiquantitative scoring system was used for evaluating the staining. The relationship of TSP-1 to VEGF expression, MVD, or clinicopathologic parameters was analyzed. Results ① TSP-1 positive expression rate was 45.8% (33/72) in the primary gastric cancer tissues, 90.3% (65/72) in the corresponding adjacent normal gastric mucosa tissues, and 50.8% (30/59) in the metastatic lymph nodes tissues. The expressions of TSP-1 in the primary gastric cancer tissues and metastatic lymph nodes tissues were significantly lower than those in the adjacent normal gastric mucosa tissues (χ2=32.710,P=0.000;χ2=25.298, P=0.000). The expression of TSP-1 had no statistical significance in the primary gastric cancer tissues as compared with in the metastatic lymph nodes tissues (χ2=0.327, P=0.568). ② The expression of TSP-1 in the metastatic lymph nodes tissues was significantly lower than that in the non-metastatic lymph nodes tissues (Z=-2.573, P=0.010). ③The expression of TSP-1 in the primary gastric cancer tissues and metastatic lymph nodes tissues suggested a negative correlation with VEGF (rs=-0.309, P=0.008;rs=-0.269, P=0.040) and MVD (rs=-0.348, P=0.003;rs=-0.272, P=0.037). Conclusions TSP-1 expression is down-regulated and has a negative correlation with VEGF and MVD in the primary gastric cancer and the metastatic lymph nodes tissues. According to the present results, it seems likely that TSP-1 is a tumor angiogenesis inhibitor.
Objective To investigate the effects of adenovirus-mediated melanoma differentiation-associated gene-7 (mda-7)/IL-24 and/or adriamycin (ADM) on transplanted human hepatoma in nude mice and to explore a new way for hepatoma gene therapy combined with chemotherapy. Methods The recombinant adenovirus vector carrying Ad.mda-7 was constructed; Ad.mda-7 and/or ADM were injected into the tumor-bearing mice. Their effects on the growth of the tumor and the survival time of the mice were observed. The expressions of VEGF and TGF-β1 were detected by an immunohistochemistry method. Results Ad.mda-7 was constructed and expressed in vivo successfully. Compared with other three groups 〔control group (43.4±1.67) d, ADM group (64.2±4.14) d, Ad.mda-7 group (61.4±1.67) d〕, the mice treated with Ad.mda-7 combined with ADM had longer average survival time 〔(83.8±4.82) d, P<0.01〕; the average size of tumor treated with Ad.mda-7 combined with ADM diminished significantly compared with that treated with ADM or Ad.mda-7 separately (P<0.01). VEGF and TGF-β1 expressions of Ad.mda-7 group were (56.2±7.7)%, (35.2±4.5)%, respectively, and were lower than those in ADM group (VEGF: P<0.05; TGF-β1: P<0.01). VEGF expression of Ad.mda-7+ADM group was (37.3±5.0)%, and was significantly lower than that in other three groups (P<0.01). TGF-β1 expression of Ad.mda-7+ADM group was (31.2±3.1)% and significantly lower than that in control group and ADM group (P<0.01), however, there was no significant difference compared with Ad.mda-7 group (Pgt;0.05). Conclusion Ad.mda-7 combined with ADM has b antitumor potency and synergistic effects and suppresses the growth of human HCC xenograft in nude mice, possibly by inducing the apoptosis of hepatoma cell lines and suppressing tumor angiogenesis.
Objective To investigate the serum levels of endostatin and vascular endothelial growth factor ( VEGF) at different therapy stages of mouse Lewis lung carcinoma, and elucidate the relation to the progress and prognosis of tumor. Methods Forty-four Lewis lung carcinoma-bearing C57BL/6 mice were randomly divided into 4 groups, ie. a non-therapy group, a chemotherapy group, a gene therapy group, and a combination therapy group ( chemotherapy plus gene therapy) . Eleven healthy mice were included as normal control group. Serum was collected on the 0th, 5th, 19th day after therapy for measurement of endostatin and VEGF by ELISA. The correlations were analysed between endostatin and VEGF levels in each group. Results ( 1) The serum endostatin levels had no significant difference in all groups on the 0th day,but increased significantly on the 5th day in the gene and combination therapy groups than those in other three groups ( all P lt;0. 01) . Then the endostatin level decreased on the 19th day in the gene and combination therapy groups, but still higher than those in the chemotherapy group and the normal group. ( 2 ) On the contrary, serum VEGF levels of the gene and combination therapy groups decreased significantly on the 5th day and increased little on the 19th day, which were both significant lower than those in chemotherapy group on the 5th and 19th day( all P lt; 0. 05) . There were significant diferences between the three therapy groups and the non-therapy group( all P lt;0. 05) . ( 3) Negative correlations between VEGF and endostatin levels were revealed in the gene and combination therapy groups ( r = - 0. 77 and - 0. 761 respectively) .Correlation was not found in the non-therapy and chemotherapy groups. Conclusion The serum levels of endostatin and VEGF might be used as monitoring indices of antiangiogenesis therapy.
Objective To investigate the effects of Hep-A and Hep-B on vascular endothelial growth factor (VEGF)-induced breakdown of blood-retinal barrier. Methods The mice were subcutaneously injected vehicle, Hep-A or Hep-B 10 mg/kg twice a day for 5 days. Then, 1 μl of 10-6mol/L VEGF were intravitreous injected. After 6 hours, 13.7×104Bq/g3H-mannital were injected intraperitoneally. The mice were sacrificed and the retinas, lungs, kidneys were removed and examined for radioactivity. The result were analyzed using SPSS software to calculate and compare retina/lung and etina/kidney leakage ratio among groups of different treatment. Result The retina/lung and retina/kidney leakage ratio were 0.38±0.04 and 0.21±0.03 respectively in normal mice; increased significantly to 1.05±0.11 and 0.46±0.04 respectively in model mice, both Plt;0.01 compared to those in normal mice; decreased to 0.59±0.06 and 0.32±0.03 respectively in mice treated with Hep-A, both Plt;0.01 compared to those in model mice; decreased 0.54±0.04 and 0.35±0.03 in mice treated with Hep-B,both Plt;0.01 compared to those in model mice. Conclusion Hep-A and Hep-B can significantly reduce VEGF-induced breakdown of blood-retinal barrier in mice. Chin J Ocul Fundus Dis,2004,20:352-354)
Objective To investigate clinical significance of serum VEGF-C level and C-erbB-2 protein expression in patients with breast cancer. Methods Sixty-two female patients with breast invasive ductal cancer and breast benign lesion were respectively selected. Serum VEGF-C level was detected by enzyme-linked immunosorbent assay (ELISA) before operation and at one month after operation, and C-erbB-2 protein expression in tissues of breast cancer was detected by immunohistochemistry. Then, the relationship between serum VEGF-C level and clinicopathologic characteristics and C-erbB-2 protein expressions wereas analyzed. Results The serum VEGF-C level before operation in breast cancer patients〔(279.65±17.34) pg/ml〕 was significantly higher than that in breast benign lesions patients 〔(167.26±12.15) pg/ml〕, P<0.01. In breast cancer patients, the serum VEGF-C level before operation was higher than that at one month after operation 〔(209.45±15.23) pg/ml〕, P<0.01. The serum VEGF level was related to tumor stage (P<0.05) but not to patient age, tumor size, menopause status , lymph node metastasis or not and ER and PR expression (Pgt;0.05). The positive expression rate of C-erbB-2 protein in breast cancer patients (54.84%, 34/62) was significantly higher than that in breast benign lesion patients (11.29%, 7/62), P<0.01. Moreover, the positive expression rate of C-erbB-2 protein in breast cancer patients with axilla lymph node metastasis (69.44%) was significantly higher than that without axilla lymph node metastases (34.62%), P<0.05. The serum VEGF level increased with increasing expression intensity of C-erbB-2 protein and there was positive correlation between them (r=0.813,P<0.05). Conclusions The serum VEGF-C level in breast cancer may be conducted as an assisted marker to differential diagnosis of breast tumor. C-erbB-2 is related to lymph node metastasis of breast cancer patients. There is synergistic effect between VEGF-C and C-erbB-2 in the lymph node metastasis way of breast cancer.
Objective To observe the effect of intravitreal injection of bevacizumab (Avastin, IVB) on the expression of integrin-linked kinase (ILK) in fibrovascular membranes and the number of vascular endothelial cells (VECs) in proliferative diabetic retinopathy (PDR). Methods Twenty-four fibrovascular membrane samples were collected during pars plana vitrectomy in 24 patients with PDR. 12 PDR patients had received a single 1.25 mg IVB 7 days preoperatively (bevacizumab group), the other 12 patients (non-bevacizumab group) had not received IVB. For each of 24 fibrovascular membranes specimen, the number of VECs in the membranes were counted after staining with hematoxylin-eosin and von willebrand factor. Expressions of ILK in the fibrovascular membranes were detected through immunohistochemistry analysis. Results Immunohistochemistry revealed that ILK was highly expressed in all of 24 fibrovascular membranes of PDR.The average optical density of ILK expression level in bevacizumab and non-bevacizumab group were (127.78plusmn;15.08) and (129.03plusmn;16.26) respectively, the difference was not statistically significant (t=0.330,P=0.745).The number of VECs in fibrovascular membranes in bevacizumab and non-bevacizumab group were 21.50plusmn;3.94 and 41.33plusmn;7.44 respectively, the difference was statistically significant (t=3.872,P=0.003). Conclusions ILK was expressed in fibrovascular membranes of PDR. IVB can decrease the number of VECs during the process of PDR, but it can not affect the expression of ILK protein.