[Correlation between the expression of angiopoietins and their receptor and angiogenesis in gastric cancers].
OBJECTIVE
To explore the effects of angiopoietins (Ang-1 and Ang-2) and Tie-2 expression on microvessel density (MVD) in gastric cancers.


METHODS
By using semiquantitative RT-PCR, immunohistochemistry and image analysis system, the expression of Ang-1, Ang-2, Tie-2 mRNA and their proteins were detected in 68 primary gastric cancers and their adjacent normal tissues. Microvessel density (MVD) was figured out based on CD34 immunohistochemical staining.


RESULTS
The expression of all Ang-1, Ang -2, Tie-2 mRNA and their proteins was detected in gastric cancers and their paired adjacent gastric mucosa tissues. A negative correlation between Ang-1 protein, Tie-2 mRNA and MVD in gastric cancers was observed (r = -0.440, r = -0.267; P < 0.05), while the relation between Ang-2 mRNA and its protein, Ang-2/Ang-1 protein ratio with MVD were positive (r = 0.319, r = 0.729, r = 0.739; P < 0.05). It was found that MVD in groups with Ang-2 mRNA T/N ratio over 1.2 (the ratio of Ang-2 mRNA in gastric cancers and its adjacent normal mucosa) was higher than that in those with a ratio under 1.2, revealed by analysing the effects of Ang-1 and Ang-2 mRNA T/N ratio on MVD in gastric cancers.


CONCLUSIONS
Ang-1 activates Tie-2 receptor, whereas Ang-2 antagonizes Ang-1 in the angiogenesis, and the Ang-2/Ang-1 ratio determines angiogenesis and tumor growth in gastric cancers. When the expression of Ang-2 is high and Ang-1 is low, the angiogenesis in gastric cancers is promoted, otherwise oppositely. The role of Ang-2 is dominant in the effect of Angs and their receptor on angiogenesis in gastric cancers.
Zhang
Zhen-zhen
ZZ
Department of Pathology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, China.
Zhang
Sheng
S
Lin
Jian-yin
JY
Huang
Pei-sheng
PS
Chen
Yu-peng
YP
D042683:Angiopoietin-1 / Q000096:biosynthesis* / Q000235:genetics; D042702:Angiopoietin-2 / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008833:Microcirculation / Q000473:pathology; D008875:Middle Aged; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000209:etiology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D042787:Receptor, TIE-2 / Q000096:biosynthesis* / Q000235:genetics; D013274:Stomach Neoplasms / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology
D042683:Angiopoietin-1; D042702:Angiopoietin-2; D012333:RNA, Messenger; D042787:Receptor, TIE-2