E-cadherin expression is inversely proportional to tumor size in experimental liver metastases.
OBJECTIVE
The role of E-cadherin in the metastatic process remains controversial. In this study, we examined what role E-cadherin plays in relation to tumor size and microvessel density (MVD) of the liver metastatic lesion.


METHODS
In F344 male rats, metastatic lesions were made by injecting RCN-9 cells into the spleen. We performed an immunohistochemical evaluation of E-cadherin and MVD in the metastatic lesions. According to a previous report, we focused on tumor sizes ranging from 2 to 3 mm, and the metastatic nodules were divided into two groups considering the value of the MVD.


RESULTS
The expression of E-cadherin was inversely proportional to tumor size (r = -0.882, P < 0.0001). MVD was directly proportional to metastatic tumor size (r = 0.726, P = 0.001). MVD in group A, in which the tumor size was 2.3 mm or more, was significantly higher than that in group B, in which the tumor size was less than 2.3 mm (3.13 +/- 1.65% vs 1.75 +/- 0.27%; P = 0.0069). The expression ratio of E-cadherin in group A was 28.21 +/- 16.36%, while it was 82.33 +/- 16.35% in group B (P = 0.0003).


CONCLUSIONS
In liver metastasis, E-cadherin's function is preserved when the tumor is small and E-cadherin's expression is reduced in large tumors in which neovascularization is increased.
Third Department of Surgery, Nihon University School of Medicine, Tokyo, 179-0072, Japan.
Hideaki
H
Karube
Hideki
H
Masuda
Yukimoto
Y
Ishii
Tadatoshi
T
Takayama
D000818:Animals; D000906:Antibodies; D015820:Cadherins / Q000032:analysis / Q000096:biosynthesis* / Q000276:immunology; D003110:Colonic Neoplasms / Q000473:pathology; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000098:blood supply / Q000737:chemistry* / Q000556:secondary*; D008297:Male; D008833:Microcirculation; D009368:Neoplasm Transplantation; D051381:Rats; D011916:Rats, Inbred F344; D013154:Spleen
D000906:Antibodies; D015820:Cadherins