[The influence of anthracosis and p16(ink4a) gene abberant methylation to the oncogenesis and progression of small pulmonary adenocarcinoma.].

BACKGROUND

Anthracosis is black dust matter deposition in the pulmonary parenchyma, which can cause bronchial deformity and destruction. Previously reported, anthracosis is closely correlated to the oncogenesis and progression of small pulmonary adenocarcinoma and p16(ink4a) gene aberrant methylation was closely associated with lung carcinogenesis. In this study, we want to characterize the influence of anthracosis and p16(ink4a) gene aberrant methylation on small adenocarcinoma.

METHODS

DNA was bisulfite modified and then Methylation Specific PCR was used to detect p16(ink4a) gene aberrant methylation, and black dust matter was extracted from lung tissues, the absolute absorbance (A) detected by densitometry was defined as anthracotic index (AI). The histopathologic diagnosis was according to Noguchi's classification for small pulmonary adenocarcinoma.

RESULTS

For heavy smokers, the mean AI was significantly higher than that of nonsmokers (P =0.005) and the frequency of p16(ink4a) gene aberrant methylation was also significantly higher than that of nonsmokers (P =0.023). The frequency of p16(ink4a) gene aberrant methylation of early stage small adenocarcinoma was lower than that of advanced and poor differentiated small adenocarcinoma, otherwise p16(ink4a) protein expression of early stage small adenocarcinoma was significantly higher than that of poor differentiated small adenocarcinoma (P =0.032).

CONCLUSIONS

AI and p16(ink4a) gene aberrant methylation detection could be used as a combined potential biomarker of small adenocarcinoma.