Serum p53 antibodies in patients affected with ulcerative colitis

During tumor progression, the accumulation in genetic alterations is a fundamental characteristic of malignant cells. p53 gene is frequently mutated in human tumor. Cellular accumulation of p53 protein can initiate an immune response with generation of circulating anti-p53 antibodies. Patients with ulcerative colitis have an increased risk of developing colorectal neoplasm and, among the different genes involved in carcinogenesis, p53 may play a key role. Sera and tissues from 97 patients (M = 53, F = 44) affected with ulcerative colitis (UC) were collected. Serum anti-p53 antibodies (p53Abs) were detected in duplicate with ELISA method. Serum p53Abs were detectable in 9.3% (9/97) of patients affected with UC. In these patients, the titer of p53Ab ranged between 3.1 and 14.9 U/mL (mean, 6.6 U/mL; SD, 4.64). Serum p53Abs were undetectable in control group. With an immunoluminometric assay for the quantitative determination of p53, we found 9/97 positive samples (greater than or equal to0.69 mg/mg of total proteins). In contrast, the samples of the remaining 89 patients were found negative (less than or equal to0.30 mg/mg of total proteins). All patients that were positive for anti-p53 antibodies were also positive with p53 protein accumulation in the tissue of colonic biopsies. In UC, follow-up with colonoscopy has several advantages. The colonoscopy is not well accepted by patients, and poor patient observance has the potential to seriously devalue the technique as a screening tool, despite practical considerations of competence within endoscopy service. Serological detection of p53Abs by enzyme-linked immunosorbent assay (ELISA) is easy to perform, does not require tumor specimen, can be performed in a routine diagnostic procedure, may be used in clinical practice, and could facilitate physicians in patient monitoring. We suggest that serum p53Abs assessment, indirect marker for p53 gene mutations, and abnormally high p53 protein levels could be considered to have a potential for use as a complementary test to improve surveillance program performance.