title: Colorectal cancer relapse: allelic alterations associated with tumour marker overexpression.
abstract: The objective of the present study was to assess the prognostic value of allelic alterations in comparison with clinical prognostic factors (age and gender, clinical stage, lymph node involvement, tissue tumour marker expression) and clinical outcomes (disease relapse and overall survival time) in colorectal cancer patients. Polymerase chain reaction was performed on the DNA of 72 colorectal samples (from 36 colorectal cancer patients) using primers D17S513 and D17S514. Carbohydrate antigen 19-9 (CA 19-9) marker was determined in tumour sections by enzyme immunoassay. Tumours were considered to exhibit allelic alterations if the microsatellite region adjacent to the p53 locus in chromosome 17 either gained or lost repeated sequences. Allelic alterations were detected in 44% of tumour samples. Patients with more than 3 involved lymph nodes had more frequent allelic alterations (p < 0.002). The allelic alteration status was compared with tumour CA 19-9 expression, which showed statistically significantly higher values within the allelic alterations group (p < 0.005). Multivariate analyses confirmed that tumours with allelic alterations had a higher probability of disease relapse (odds ratio 7.3, p = 0.01). This is the first report showing an association between allelic alteration and overexpression of a tissue tumour marker protein and established risk factors. These results could be considered useful additional prognostic information for colorectal cancer.
authors.affiliation: Centro de Investigación, Hospital Universitario 12 de Octubre, Madrid, Spain. i_vegh@hotmail.com
authors.forename: Irene
authors.initials: I
authors.lastname: Vegh
authors.forename: Javier
authors.initials: J
authors.lastname: De-La-Cruz
authors.forename: Susana
authors.initials: S
authors.lastname: Navarro
authors.forename: Carlos
authors.initials: C
authors.lastname: Morales
authors.forename: Francisco
authors.initials: F
authors.lastname: Colina
authors.forename: Alfredo
authors.initials: A
authors.lastname: Abad
authors.forename: Angel
authors.initials: A
authors.lastname: De-La-Calle
authors.forename: Rafael
authors.initials: R
authors.lastname: Enriquez-De-Salamanca
authors.forename: Enrique
authors.initials: E
authors.lastname: Moreno-González
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics* / Q000473:pathology; D000483:Alleles; D014408:Biomarkers, Tumor / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000473:pathology; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis; D015854:Up-Regulation
chemical_list: D014408:Biomarkers, Tumor