[The effect of RhoE on CD44 promoter and the malignant behaviors of colorectal cancer cell].

Objective: To study the effect of RhoE on the transcriptional regulation of cd44 and in vivo tumorigenicity of nude mice.

Methods: cd44 promoter was amplified from human embryonic kidney HEK293 cells with PCR and insert into Dual-Luciferase Reporter plasmid pGL3-Basic. After confirmed with sequence analysis, the generated recombinant was transfected into SW480 and LoVo cells to monitor their activity.

[The effect of small GTPase Cdc42 on the multidrug resistance of oxaliplatin-resistant colon cancer cell lines].

Objective: To determine the effect of cell division cycle42 (Cdc42) on the multidrug resistance of oxaliplatin-resistant human colon cancer cells.

Methods: The protein expression levels of Cdc42 in oxaliplatin-resistant colon cancer cells and parental cells were examined with Western blot. pDEST26-His-Cdc42 was transfected by lipofectamine 2000 into SW480 and Colo320 cells with low expression of Cdc42.

[The affect of Si-Rac1b on the malignant biological behaviors of colorectal cancer cell].

Objective: To observe the affect of Small interfering RNA Rac1b (Si-Rac1b) on the malignant biological behaviors of colorectal cancer cell including the proliferation, migration, invasion and apoptosis of the cells.

Methods: Mediated by lipofectamine 2000, Si-Rac1b was transfected into colorectal cancer cell line SW1116 (with overexpression of Rac1b). The expression of Rac1b was detected by Western blotting and RT-PCR.

[The effect of RhoA and proteasome inhibitor MG132 on angiogenesis in tumors].

Objective: To investigate the effect of RhoA to VEGF, HIF-1alpha and MVD (microvascular density) and the effect of MG132 to RhoA.

Methods: The constitutively-active mutant vectors of RhoA (pCEFL-GST-V14RhoA) were transfected into gastric cancer cell line MKN-45 by Lipofectamine 2000, single clones were selected by G418 and identified with western blot. The content of VEGF in the conditioned media was detected by ELISA.