ICAM-1 or Anti-ICAM-1 was substituted by PBS 5 muL on the day 10 or day 6 after incubation. Three days later, the CAMs were photographed in vivo, excised, sectioned and the number of microvessels was counted. In ICAM-1 group, there was increased number of microvessels arranged radially with "spoked-wheel" pattern around the gelatin sponges. The new microvessels growing perpendicularly to gelatin sponges were observed. The number of the microvessels growing in the CAM mesenchymes around the sponges in 3 subgroups was higher than that in control group (P<0.01), however, there was no significant difference among the 3 subgroups (P>0.05). In anti-ICAM-1 group A, the radially arranged microvessels were very unclear around the sponges contrast to that of ICAM-1 group. Few new microvessels were detected in the center of the sponges. The number of the microvessels growing in the CAM mesenchymes around the sponges in subgroup II was lower than that in control group (P<0.01). There was no significant difference in the number of the microvessels around the sponges between subgroup I and control group (P>0.05). In anti-ICAM-1 group B, the radially arranged microvessels were very unclear around the sponges contrast to that of control group. New microvessels were very scarce in the center of the sponges. The number of the microvessels growing in the CAM mesenchymes around the sponges in the 2 subgroups were less than that in control group (P<0.01), and there was significant difference between the 2 subgroups (P<0.05). It was suggested that ICAM-1 could induce angiogenesis and support the survival of microvessels, and ICAM-1 was involved in embryonic angiogenesis.
The action mechanism of matrix metalloproteinases-2 (MMP-2) and tissue inhibitor of metalloproteinases-2 (TIMP-2) in the genesis, development and degeneration of haemangioma was investigated by detecting their expression in the tissue of haemangioma in different phases by using the immunohistochemistry. Fifty paraffin-embedded specimens of skin capillary haemangioma were collected, which were documented in the Department of Pathology, Renmin Hospital of Wuhan University from 2000 to 2006. All samples were stained by regular HE method, and proliferative cell nuclear antigen (PCNA) was tested by immunohistochemical S-P method. The samples were classified according to the Mulliken criteria and the expression pattern of PCNA. Immunohistochemical S-P method was applied to detect the expression of MMP-2 and TIMP-2 in proliferative and degenerative phases of cutaneous capillary haemangioma, and in normal skin tissues. In combination with the detection of the expression of factor VIII-related antigen, it was verified that in haemangioma tissues, the cells expressing MMP-2 and TIMP-2 were vascular endothelial cells. The MMP-2 and TIMP-2 expression was quantitatively analyzed by image analysis system (HPIAS-1000), and one-way ANOVA(107) and SNK(q) test were done to analyze average absorbance (A) and positive area rate of immunohistochemically positive particles by using SPSS11.5. The results showed: (1) Among 50 samples of haemangioma, there were 26 proliferative haemangiomas, and 24 degenerative haemangiomas, respectively; (2) The expression of MMP-2 was weak in normal vascular endothelial cells, cytoplasm of connective tissues and extracellular matrix around blood vessels. The expression of MMP-2 in proliferative group was significantly higher than in degenerative group and control group (normal skin) (P<0.05), but there was no statistically significant difference between the latter two groups; (3) TIMP-2 was highly expressed in normal tissues, degenerative vascular endothelial cells, cytoplasm of connective tissues and extracellular matrix around blood vessels. The expression level of TIMP-2 in proliferative phase was significantly lower than in degenerative phase (P<0.05), and the expression of TIMP-2 in proliferative phase was significantly different from that in degenerative phase and normal tissues (P<0.05). It was concluded that in proliferative phase of haemangioma, MMP-2 may promote over-proliferation of endothelial cells of haemangioma, and in degenerative phase, TIMP-2 can inhibit the proliferation of endothelial cells of haemangioma. The two substances play important roles in the genesis, development and degeneration of haemangiomas.
The effect of transfection of antisense vascular endothelial growth factor (VEGF) gene on the growth of hemangioma was studied. A total of 49 cases of capillary hemangiomas of the skin were collected. Immunohistochemical method was used to detect the expression of PCNA in hemangioma tissues. According to the finding, 49 cases of hemangiomas fell into proliferating phase (27 cases) and involuting phase (22 cases) respectively. Another 5 cases of normal skin tissues adjacent to the tumor tissues served as control. Immunohistochemical staining was performed to detect the expression of VEGF in the tumor tissues and the normal tissues. The average absorbance (A) values and the average positive area rate of VEGF were measured by image analysis system (HPIAS-2000). Endothelial cells from the tumor tissues in proliferating phase were cultured. Eukaryotic expression vector was constructed by sub-cloning, and transfected into human hemangioma endothelial cells by using cation liposome as vector. The expression of VEGF mRNA and protein was detected by RT-PCR and indirect immunofluorescence assay (IFA), respectively, and the biological characteristics of the transfected endothelial cells were examined by MTT assay and flow cytometry (FCM) after transfection. Immunohistochemical results showed that the expression of VEGF in proliferating endothelial cells was remarkably higher than those in involuting endothelial cells and normal endothelial cells (P<0.01), but there was no significant difference in the expression of VEGF between involuting endothelial cells and normal ones (P>0.01). Electrophoresis and sequencing indicated that the eukaryotic expression vector containing antisense VEGF gene, i.e. pcDNA3.1-VEGF, was successfully constructed. After VEGF antisense RNA recombinant was transfected into hemangioma endothelial cells, RT-PCR revealed that the expression of VEGF mRNA in pcDNA-VEGF (V) group and blank group was obviously higher than that in pcDNA-VEGF (A) group, and that the expression of endogenous VEGF mRNA in pcDNA-VEGF (A) group was significantly inhibited. Immunohistochemical result demonstrated that, compared with blank group, there was statistically significant difference between pcDNA-VEGF (A) and pcDNA-VEGF (V) groups (P<0.01), but there was no significant difference between pcDNA-VEGF (V) group and blank group (P>0.05). The activity of endothelial cell proliferation was reduced significantly after transfection, and obvious apoptosis occurred in hemangioma endothelial cells after transfection of antisense VEGF. It was suggested that VEGF plays an important role in the pathological change of hemangiomas by promoting endothelial cell proliferation and angiogenesis. Antisense VEGF gene transfection could effectively inhibit the growth of hemanioma endothelial cells.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.