Clinical significance of serum p53 antibody detection on chemosensitivity assay in human colorectal cancer

Background and Objectives: Alteration of the p53 gene product occurs freque ntly during progression of colorectal cancer. Recently, mutated p53 protein was found to induce the production of anti-p53 antibodies in the serum of patients. The purpose of this study was to evaluate the relationship betwee n p53 status in serum and chemosensitivity in resectable colorectal cancer patients. Methods: A total of 22 patients with primary colorectal cancer who underwen t surgical treatment were examined for chemosensitivity with iable tumor sa mples using the Histoculture Drug Response Assay (HDRA). Serum samples of t hese patients for p53 antibodies were obtained before tumor resection and a ssayed in duplicate using an enzyme-linked immunosorbent assay kit. Results: The inhibition index of 5-fluorouracil and cis-diamminedichloropla tinum (CDDP), determined by the HDRA method, in the seropositive group was significantly lower than that in the seronegative group (P < 0.01). Further more, significant statistical differences in chemosensitivity to 5-fluorour acil and CDDP were revealed depending on the presence of serum p53 antibodi es. Conclusions: Detection of serum p53 antibodies, which reflects p53 mutation s in tumor tissue, is a simpler method which correlates with chemosensitivi ty and may contribute to the selection of favorable; chemotherapeutic strat egies for colorectal cancer. J. Surg. Oncol. 1999:71:112-116. (C) 1999 Wile y-Liss, Inc.