Abstract
The main features of cancer cells that distinguish them from normal cells are uncontrolled synthesis of molecules that stimulate growth and insensitivity to apoptotic stimuli such as radiation or chemotherapy. Smac/DIABLO (second mitochondria-derived activator of caspases/direct IAP binding protein with low pI) is a pro-apoptogenic mitochondrial protein that is released from mitochondria similarly to cytochrom c, AIF, Omi/HtrA2. Smac/DIABLO inhibits proteases and in that way caspases may avoid inactivation, which allows progress of apoptosis pathway. Better understanding of a signal apoptotic transduction in cancer cells gives hope to obtain drugs that could be used in cancer therapy. The aim of the study was to investigate the level of proapoptotic signals coming from pre-mitochondrial and mitochondrial sources in lung cancer depending on selected clinico-pathological parameters. The p53, Smac/DIABLO and Omi/Htr2 mRNA relative expression was evaluated in lung cancer specimens taken from 39 male patients. The study revealed lack of significant differences in p53, Smac/DIALO and Omi/Htr2 mRNA expression according to the histological type and grade of cancer differentiation as well as age categories. It could be concluded that the level of apoptotic signalling represented by p53, Smac/DIABLO and Omi/Htr2 in the tested specimens is comparable despite the tested parameters.
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