Oncoproteins as biomarkers of a preclinical form of cancer of the respiratory tract induced by environmental carcinogens.

Experimental data and clinical observations indicate that an increased expression of oncogenes or their point mutations play an essential role in the process of carcinogenesis. It was important to find out that environmental and occupational carcinogens activate cellular oncogenes and contribute to increased amounts or occurrence of mutated oncoproteins. The latter are responsible for activating mechanisms which further the neoplastic transformation of cells. The researches are mainly concerned about two oncoproteins: oncoprotein coded by the ras oncogene--called p21 protein and oncoprotein coded by the erbB-2 oncogene--called p185 protein. Investigations performed on neoplastic cells show that the neoplastic transformation process involves not only the afore-said oncogenes and their oncoproteins but also other oncogenes, and that the process itself required activating of more than one oncogene. At present, it is possible to use measurements of oncoproteins in the biological material which is easily available. Due to this fact, a number of works in which measurements of oncoproteins in blood serum were used to assess cancer risk in persons exposed to carcinogens present at the work place, have been published.