Relationship between expression of CD105 and growth factors in malignant tumors of gastrointestinal tract and its significance.
OBJECTIVE
Angiogenesis is an important step in the growth of solid malignant tumors. A number of angiogenic factors have been found such as transforming growth factor beta1 (TGF-beta1) and vascular endothelial growth factor (VEGF). However, the roles of TGF-beta1 and VEGF in gastrointestinal carcinogenesis are still unclear. This study was to investigate the expressions of TGF-beta1 and VEGF in gastrointestinal tract malignant tumors, as well as their association with microvessel density (MVD). At the same time, we also observed the localization of TGF-beta1 and its receptor CD105 in gastric malignant tumors.


METHODS
The expressions of TGF-beta1 and CD105 were detected in 55 fresh specimens of gastric carcinoma and VEGF and CD105 in 44 fresh specimens of colorectal carcinoma by immunohistochemical staining (S-ABC). TGF-beta1 and CD105 in 55 gastric carcinoma tissues on the same slide were detected by using double-stain Immunohistochemistry (DS-ABC).


RESULTS
Among the 55 cases of gastric carcinoma tissues, 30 were positive for TGF-beta1 (54.55%). The MVD of TGF-beta1 strong positive group (++ approximately +++ 23.22 +/- 5.8) was significantly higher than that of weak positive group (+17.56 +/- 7.2) and negative group (- 17.46 +/- 3.9) (q=4.5, q=5.3207, respectively, P<0.01). In the areas of high expression of TGF-beta1, MVD and the expression of CD105 were also high. Among the 44 cases of colonic carcinoma tissues, 26 were positive for VEGF (59.1%). The expressions of both VEGF and CD105 (MVD) were related with the depth of invasion (F=5.438, P<0.05; F=4.168, P=0.05), lymph node metastasis (F=10.311, P<0.01; F=20.282, P<0.01) and Dukes stage (F=6.196, P<0.01; F=10.274, P<0.01), but not with histological grade (F=0.487, P>0.05). There was a significant correlation between the expression of VEGF and CD105 (MVD) (r=0.720, P<0.01).


CONCLUSIONS
Over-expression of TGF-beta1 and VEGF acts as stimulating factors of angiogenesis in gastrointestinal tumors. CD105, as a receptor of TGF-beta1, can regulate the biological effect of TGF-beta1 in tumor angiogenesis. MVD marked by CD105 is more suitable for detecting newborn blood vessels.
Yu
Jian-Xian
JX
Department of Pathology, Qingdao Municipal Hospital, Qingdao 266011, Shandong Province, China. yujianxian@hotmail.com
Zhang
Xiao-Tun
XT
Liao
Yong-Qiang
YQ
Zhang
Qi-Yi
QY
Chen
Hua
H
Lin
Mei
M
Kumar
Shant
S
D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D003110:Colonic Neoplasms / Q000098:blood supply / Q000473:pathology*; D000071063:Endoglin; D006801:Humans; D008207:Lymphatic Metastasis; D008833:Microcirculation / Q000473:pathology; D008875:Middle Aged; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000235:genetics / Q000473:pathology; D011956:Receptors, Cell Surface; D013274:Stomach Neoplasms / Q000098:blood supply / Q000473:pathology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000032:analysis*; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis
D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; D011956:Receptors, Cell Surface; D019010:Vascular Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A