Anti-p53 autoantibody as early diagnostic and prognostic marker of bronchogenic carcinoma in smokers

Abstract

Background Mutations in the tumor protein 53 (TP53) gene can lead to expression of mutant p53 proteins that accumulate in cancer cells and can induce circulating p53 antibodies in patients with cancer. Neoplastic transformation leads to elevated plasma sialic acid concentration through shedding or secreting of sialic acid from tumor cell surfaces. Our work aims to evaluate the presence and prognostic role of these antibodies and sialic acid in patients with lung cancer. Patients and methods A total of 30 patients with lung cancer (five patients were presented with stage I, 10 patients with stage II, 10 patients with stage III, and five patients with stage IV) and 60 with nonmalignant disorders (30 smokers and 30 apparently healthy individuals) were evaluated for p53 antibodies by enzyme-linked immunosorbent assay and sialic acid by colorimetric methods. Results Anti-p53 antibodies and sialic acids levels in patients with bronchogenic carcinoma were significantly higher than smokers, and both levels were significantly higher than healthy controls (P<0.001). There was no statistically significant difference between stages III and IV of bronchogenic carcinoma of serum anti-p53 antibodies and sialic acid, but there was a statistically significant difference between stages I, II, and III, where the levels in stage III of bronchogenic carcinoma were significantly higher than stage II, and both levels were significantly higher than in stage I. There was a positive correlation between serum levels of anti P53 autoantibodies and the smoking index of the same patients. There was a positive correlation between serum levels of sialic acid and anti-p53 antibodies in the same patients with bronchogenic carcinoma. Conclusion Anti-p53 antibodies and sialic acid can be considered as sensitive for the biochemical changes associated with smoking and lung cancer. They may be used as markers for early diagnosis of lung cancer, and presence of them in smokers with primary lung cancer correlates with the severity and bad prognostic outcome of the disease.

Keywords

• bronchogenic carcinoma
• p53 gene mutations
• p53 protein expression
• sialic acid
• tumor protein 53