Survivin expression in atypical adenomatous hyperplasia of the lung

Few studies have investigated apoptosis-related factors in atypical adenomatous hyperplasia (AAH) and nonmucinous bronchioloalveolar carcinoma. We studied the expression of survivin, bcl-2, and p53 in 29 AAH lesions (low-grade, 11; high-grade, 18) and 40 nonmucinous BACs using immunohistochemical analysis and of survivin messenger RNA in 6 nonmucinous BACs using reverse transcription-polymerase chain reaction (RT-PCR). The incidence of positive survivin expression was 9% (1/11) in low-grade AAH, 89% (16/18) in high-grade AAH, and 100% (40/40) in nonmucinous BAC. Statistically significant differences were found between low-grade and high-grade AAH and between high-grade AAH and nonmucinous BAC. The percentages obtained for positive bcl-2 and p53 expression were 18% (2/11) and 0% (0/11) in low-grade AAH, respectively, and 28% (5/18) for both in high-grade AAH and 48% (19/40) for both in nonmucinous BAC. In RT-PCR, the intensity of survivin messenger RNA expression was stronger in nonmucinous BACs than in normal lung tissue samples. Thus, the expression of the 3 antibodies in high-grade AAH was intermediate between low-grade AAH and nonmucinous BAC. High-grade AAH may be closely related to nonmucinous BAC.