ANTI-P53 ANTIBODIES IN SERA FROM PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY-DISEASE CAN PREDATE A DIAGNOSIS OF CANCER

Serum anti-p53 antibodies (p53-Abs) may be surrogate markers for both p53 alterations and preclinical cancer. Ancillary to a prospective tri al to abate progressive development of clinical stages of chronic obst ructive pulmonary disease, we conducted a retrospective, nested case c ontrol study, Twenty-three cases were diagnosed with cancer during the trial, Enzyme immunoassay, immunoblotting, and immunoprecipitation we re used to detect p53-Abs in serum, immunohistochemistry (IHC) to dete ct p53 accumulation, and single-strand conformation polymorphism and D NA sequencing to detect p53 mutations in tumor samples, p53-Abs were d etected by three types of assays in five (23%) of the cancer patients, 80% of whom had detectable p53-Abs before diagnosis: 2 lung cancers ( 7 and 6 months before), 1 prostate cancer (11 months), and 1 breast ca ncer (5 months), Four Ab-positive patients had IHC-positive tumors. Tw o of 4 Ab-positive patients and 2 of 14 Ab-negative had p53 missense m utations or base pair deletion and LHC-positive tumors, The 44 noncanc er COPD controls, matched with the cancer cases for age, gender, and s moking habits, were negative for p53-Abs, These results indicate that p53-Abs may facilitate the early diagnosis of cancer in a subset of sm okers with chronic obstructive pulmonary disease who are at an increas ed cancer risk.