Aim To investigate the expression of CD31 , CD105 , HIF-1αand VEGF in xenografts tumor of HT-29 tumor cells during different stages of growth. Methods HT-29 tumor cells were transplanted into nude mice, the tumor was removed when the tumor volumes reached <100 mm3 , 100 ~300 mm3 and >300 mm3 respectively. Immunochemical method was a-dopted to detect the expression of CD31 , CD105 , HIF-1α and VEGF. Results HT-29 xenografts tumor vol-umes <100 mm3 , 100 ~300 mm3 , and >300 mm3 showed expressions with CD31-MVD at 37.40±4.17 , 18.80±1.72 and 14.20±2.23 respectively; CD105-MVD at 22.80 ±3.54 , 15.60 ±1.35 and 10.20 ±2.48; positive expression rate of VEGF was 26.20%
±0.83%,40.73% ±6.29% and 13.41% ±1.20%respectively; while positive expression rate of HIF-1αwas 3.20% ± 2.97%, 11.89% ± 1.94% and 80.62% ±3.47% respectively. On the other hand, for different volumes group, CD31-MVD, CD105-MVD, VEGF and HIF-1αexpression ratios had signifi-cant differences ( P <0.01 ) . Conclusions The ex-pression of MVD and vascular-related factors within the tumor caused by HT-29 xenografts tumor in nude mice at different growth stages was varied. There was a cer-tain correlation between tumor volume and MVD, VEGF, HIF-1α.