M V Croce1, V C Sálice, E Lacunza, A Segal-Eiras. 1. Centro de Investigaciones Inmunológicas Básicas y Aplicadas, Facultad de Ciencias Médicas, UNLP, La Plata, Argentina.
Abstract
OBJECTIVES: 1- to detect alpha 1-acid glycoprotein (AGP) and sialyl Lewis x (sLex) in colorectal malignant, benign and normal samples; 2- to isolate AGP from colorectal cancer and 3- to study its immunoreactivity with an anti-sLex monoclonal antibody (MAb). MATERIALS AND METHODS: tissue and serum samples from 88 patients with colorectal cancer, 22 adenomas and 23 normal were included. Expression of AGP and sLex was studied by immunohistochemistry (IHC); isolation approach: AGP was precipitated with ammonium sulphate and immunoprecipitated with anti-AGP MAb. The immune complex formed was isolated by protein A-Sepharose CL-4B affinity chromatography and further eluted; fractions were analysed by SDS-PAGE and Western-blot. Statistical analysis was performed by means of Principal Component Analysis. RESULTS: By Western blot employing anti-AGP MAb and sLex MAbs, isolated fractions from malignant samples showed a band at about 45 kD. IHC revealed that AGP was expressed in 70% of colorectal carcinoma samples, 50% of benign and 35% of normals. SLex was detected in 31% of malignant samples, 41% of benign and in one normal sample. In malignant samples, AGP reaction comprised the whole specimen with a strong and homogeneous staining while normal and benign samples showed a restricted reaction. In cancer, sLex expression consisted in an intense reactivity in membrane, cellular debris and some cytoplasmic foci while normal and benign samples were occasionally stained. A statistically significant positive correlation was found between AGP and sLex expression. Serum AGP levels were measured by radial immunodiffusion and statistical comparative analysis with tissue expression did not show a correlation between both parameters. CONCLUSION: AGP may constitute a carrier of sLex in colorectal cancer.
OBJECTIVES: 1- to detect alpha 1-acid glycoprotein (AGP) and sialyl Lewis x (sLex) in colorectal malignant, benign and normal samples; 2- to isolate AGP from colorectal cancer and 3- to study its immunoreactivity with an anti-sLex monoclonal antibody (MAb). MATERIALS AND METHODS: tissue and serum samples from 88 patients with colorectal cancer, 22 adenomas and 23 normal were included. Expression of AGP and sLex was studied by immunohistochemistry (IHC); isolation approach: AGP was precipitated with ammonium sulphate and immunoprecipitated with anti-AGP MAb. The immune complex formed was isolated by protein A-Sepharose CL-4B affinity chromatography and further eluted; fractions were analysed by SDS-PAGE and Western-blot. Statistical analysis was performed by means of Principal Component Analysis. RESULTS: By Western blot employing anti-AGP MAb and sLex MAbs, isolated fractions from malignant samples showed a band at about 45 kD. IHC revealed that AGP was expressed in 70% of colorectal carcinoma samples, 50% of benign and 35% of normals. SLex was detected in 31% of malignant samples, 41% of benign and in one normal sample. In malignant samples, AGP reaction comprised the whole specimen with a strong and homogeneous staining while normal and benign samples showed a restricted reaction. In cancer, sLex expression consisted in an intense reactivity in membrane, cellular debris and some cytoplasmic foci while normal and benign samples were occasionally stained. A statistically significant positive correlation was found between AGP and sLex expression. Serum AGP levels were measured by radial immunodiffusion and statistical comparative analysis with tissue expression did not show a correlation between both parameters. CONCLUSION: AGP may constitute a carrier of sLex in colorectal cancer.
Authors: Margaret Doherty; Evropi Theodoratou; Ian Walsh; Barbara Adamczyk; Henning Stöckmann; Felix Agakov; Maria Timofeeva; Irena Trbojević-Akmačić; Frano Vučković; Fergal Duffy; Ciara A McManus; Susan M Farrington; Malcolm G Dunlop; Markus Perola; Gordan Lauc; Harry Campbell; Pauline M Rudd Journal: Sci Rep Date: 2018-06-05 Impact factor: 4.379
Authors: Pauline L Pfuderer; Alexej Ballhausen; Florian Seidler; Hans-Jürgen Stark; Niels Grabe; Ian M Frayling; Ann Ager; Magnus von Knebel Doeberitz; Matthias Kloor; Aysel Ahadova Journal: Br J Cancer Date: 2019-07-30 Impact factor: 7.640
Authors: Jung-hyun Rho; Judson R Mead; W Shea Wright; Dean E Brenner; James W Stave; Jeffrey C Gildersleeve; Paul D Lampe Journal: J Proteomics Date: 2013-11-01 Impact factor: 4.044