[Insulin-like growth factors in lung precancer]

Investigation of IGF-system resulted in distinguishing two groups of processes depending on the size of the bronchi. Goblet cell metaplasia, basal cell hyperplasia with or without atypical features, squamous cell metaplasia, dysplasia 1-3, neuroendocrine cell hyperplasia, epithelial atrophy were found in the large bronchi. The same changes occurred in the bronchioli and alveoli plus adenomatous hyperplasia with or without atypia, oval and narrow structures with epithelial atrophy, atypia and proliferation. Common property was accumulation in the cells of various members of IGF system: high accumulation of IGF II, IGFBP 1,2,3,4 in dysplasia; the same plus IGFBP 11,2,3,4,5 in squamous metaplasia. Tuberculous granuloma cells are an important source of IGF II, IGFBP 2,3,4,5,6 playing a role in proliferation and apoptosis of the pulmonary epithelium.