[Suppression of osteosarcoma in vitro by coexpression of antisense VEGF165 cDNA and thymidine kinase gene].

Objective: To investigate the effect of VEGF expression in osteosarcoma cell line and the target killing effect of HSV1-TK/GCV system on transfected osteosarcoma cells under hypoxia conditions.

Methods: Eukaryotic expression plasmid with HRE promoter was constructed to express the antisense VEGF165 cDNA and Hygromycin phospho-transferase-thymidine kinase (HyTK) fusion gene. The recombinant vectors were then transfected into osteosarcoma cell line MG63 with lipofectin mediated gene transfer methods.

[Targeted inhibition of vascular endothelial growth factor (VEGF) expression in human osteosarcoma cell line by antisense VEGF165 cDNA promoted by hypoxia reaction element].

Objective: Utilizing the hypoxia inducible factor 1/hypoxia reaction element (HIF-1/ HRE) gene regulation system to construct antisense vascular endothelial growth factor (VEGF165) cDNA eukaryotic expression vector promoted by HRE, and investigate its targeted inhibiting VEGF expression of osteosarcoma cells in hypoxia environment.

Methods: Eukaryotic expression plasmid with HRE promoter was constructed containing luciferase reporter gene and antisense VEGF165 cDNA by using PCR and recombinant DNA techniques. The recombinant vectors were transfected into osteosarcoma cells with lipofectin method.

[The role of CD44 in the proliferation, adhesiveness and invasiveness of osteosarcoma cell lines].

Objective: To study the influence of CD44 a cell-matrix adhesion molecule on the proliferation, adhesiveness and invasiveness of osteosarcoma cell lines, in order to investigate the growth and invasion mechanism of osteosarcoma.

Methods: Three osteosarcoma cell lines MG-63, HOS and U2-OS were routinely cultured. Flow cytometry and Western blot analysis were used for detecting the positive rates and relative amount of CD44 protein in the three cell lines.

[Relationship between expression of c-myc and p53 in liposarcoma].

Background & Objective: The relationship between liposarcoma and gene c-myc and p53 is not clear. There are also different reports on p53 mutation in liposarcoma. This study was designed to investigate the relationship between the expression of c-myc and p53 genes and liopsarcomas.

[Expressions of CD44s, MMP-9, and Ki-67: possible association with invasion, metastasis, and recurrence of osteosarcoma].

Background & Objective: Recent research had showed that tumor cell adhesion molecular CD44 and matrix metalloproteinases (MMP) were expressed strongly in many tumors, and was associated closely with invasion and metastasis of the tumors. Ki-67 was one of the proliferative markers, which indicated the growth rate of tumor cells. However, the relationship among these markers and the invasion, metastasis, and recurrence of osteosarcoma was unclear yet.