The expression of p185(HER-2/neu) correlates with the stage of disease and survival in colorectal cancer.
OBJECTIVE
HER-2/neu oncogene encodes a transmembrane tyrosine kinase receptor that is amplified and/or overexpressed predominantly in adenocarcinomas. This phenomenon has been most intensively studied in breast carcinoma where its amplification and overexpression correlate with the overall course of disease and poor prognosis. This study was designed to investigate HER-2/neu gene expression in benign and malignant colorectal lesions and to evaluate its prognostic importance in colorectal cancer.


METHODS
Two hundred twenty-one samples of normal colon, benign lesions, and colorectal adenocarcinomas were studied for expression of HER-2/neu oncoprotein. Immunohistochemical staining of formalin-fixed, paraffin-embedded tissue sections of primary tumor and lymph nodes was performed. Immunoprecipitation followed by Western blotting of freshly frozen samples of the same tumors were also performed.


RESULTS
Normal colon mucosa, benign lesions, and adenocarcinomas clearly differed in the expression levels and histological distribution of p185(HER-2/neu). Normal mucosa was mostly negative, but significant number of benign lesions and adenocarcinomas overexpressed HER-2/neu protein. Adenocarcinomas were significantly more positive than benign lesions. The results show significant correlation with the epithelial abnormality degree and clinical parameters including Dukes' classification and relapse-free and postoperative survival period.


CONCLUSIONS
The p185(HER-2/neu) rate expression could serve as an independent prognostic factor in patients with p185(HER-2/neu)-positive colorectal malignancies.
Kapitanović
S
S
Division of Molecular Medicine, Ruder Bosković Institute, Zagreb, Croatia.
Radosević
S
S
Kapitanović
M
M
Andelinović
S
S
Ferencić
Z
Z
Tavassoli
M
M
Primorać
D
D
Sonicki
Z
Z
Spaventi
S
S
Pavelic
K
K
Spaventi
R
R
D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology*; D000236:Adenoma / Q000235:genetics* / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology*; D015870:Gene Expression; D018734:Genes, erbB-2; D006801:Humans; D006965:Hyperplasia; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D011127:Polyps / Q000235:genetics / Q000473:pathology; D011233:Precipitin Tests; D012044:Regression Analysis; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors