Assaying of p53 Autoantibodies in saliva for the detection of oral squamous cell carcinoma. A road not taken.

BACKGROUND: Autoantibody detection is a promising approach to cancer screening. Serum p53 antibodies have been time tested in various cancers, including oral squamous cell carcinoma (OSCC). This study is aimed to detect and determine the level of p53 autoantibodies (p53-AAbs) in saliva. The association of clinicopathological features among patients with and without OSCC was also explored as a novel method for the detection of autoantibodies.

METHODS: One hundred preoperative saliva samples from patients with histologically confirmed OSCC and a hundred from normal healthy individuals were collected. Anti p53 detection kit assessed levels of salivary p53-AAbs. The cut-off value was 1.3 U/mL by Enzyme-linked immunosorbent assay (ELISA). The p53-AAb levels were expressed in terms of the median and interquartile range (IQR). Fischer's exact test and Chi-square test were used to determine the association with clinicopathological features among patients with OSCC and healthy controls with tobacco consumption habits.

RESULTS: Median level of p53-AAb is 0.234 U/mL (IQR 0.18-0.37U/mL) in healthy controls and 0.285U/mL (IQR 0.16-0.58U/mL) in OSCC. p53-AAbs was positive in 15% of 100 patients with OSCC, which was statistically higher (P < 0.001) among OSCC, and controls were negative for p53-AAb. No significant correlation of p53-AAbs with the patient's age, gender, site, clinical staging (TNM), and pathologic grade was observed. However, a significant association was seen between the node involvement and salivary p53-AAbs.

CONCLUSION: Salivary p53-AAb positivity was seen in a higher proportion in OSCC patients than in healthy controls with tobacco consumption, and the levels did differ significantly among OSCC and healthy controls.