[The immunohistochemistry of cellular oncogenes in precancer and cancer of the lung].

Operative material obtained from patients with lung cancer and precancer, carcinoids, secondary tuberculosis, chronic nonspecific diseases and pulmonary lymphosarcoma was examined immunohistochemically. Expression of the oncogenes was higher in lung carcinoma than in the foci of lung epithelium regeneration, metaplasia and dysplasia. All the oncogenes in precancer and cancer may be divided into two groups by the degree of their expression: oncogenes the activation of which occurs in the same way at certain stages of tumour progression regardless of the lung carcinoma histogenesis and oncogenes expressed at certain stages depending upon the carcinoma histogenesis. The majority of oncogenes studied may be included into the second group (C-myc, ras, sis, src) and only one c-fos into the first group. The oncogenes expression may occur at the precancerous stage and precede the morphological changes in cells and tissues. The expression of some oncogenes (C-myc, sis) takes place not only in the tumour parenchyma but in the cancer stroma as well thus making the immunohistochemical method most reliable that permits one to study a true expression of oncogenes by cancer cells.