X. Sanjuan et al., DIFFERENTIAL EXPRESSION OF GALECTIN-3 AND GALECTIN-1 IN COLORECTAL-CANCER PROGRESSION, Gastroenterology, 113(6), 1997, pp. 1906-1915
Background & Aims: Galectins are beta-galactoside-binding proteins pos
sibly involved in tumor progression. The aim of this study was to dete
rmine the pattern of galectin 3 and galectin 1 expression and involvem
ent in colorectal cancer progression. Methods: Galectin 3 expression w
as examined immunohistochemically in 39 samples of normal mucosae, 25
adenomas, 87 carcinomas, and 39 lymph node metastases. Galectin 1 was
analyzed in 25 samples of mucosae, 15 adenomas, 25 carcinomas, and 11
metastases. Western blot analysis was also performed. Results: All nor
mal mucosae showed strong nuclear galectin 3 expression, which was dow
n-regulated in the neoplastic progression, because only 60% of adenoma
s, 48% of carcinomas, and 44% of metastases were strongly positive (P
< 0.0001). Cytoplasmic expression was down-regulated in adenomas (16%)
but increased again in carcinomas (64%) (P < 0.0001). Galectin 1 expr
ession was mainly detected in stromal cells and correlated with tumor
progression from normal mucosae to adenomas and carcinomas (P < 0.0001
). Conclusions: Galectin 3 expression is down-regulated in the initial
stages of neoplastic progression, whereas a dissociated cytoplasmic e
xpression increases in later phases of tumor progression. Galectin 1 i
n colorectal mucosa is predominantly a stromal product whose overexpre
ssion is associated with the neoplastic progression of colorectal canc
er.