[The Bcl-2 protein family in malignant diseases]

Programmed cell death proteins and chronic leukemia

Apoptosis or programmed cell death is a genetically regulated process of cellular suicide. Apoptosis has been implicated in a wide range of pathological conditions, and mutations in apoptotic genes play important roles in the process of malignant transformation. Chronic leukemia represents a neoplastic disorder caused primarily by defective programmed cell death, as opposed to increased cell proliferation. This paper presents the main results of our ten-year research on the apoptosis of leukemia cells. The research included the morphological aspects of the process, the effect of antineoplastic agents on the induction of apoptosis in leukemia cells and expression analysis of the proteins involved in programmed cell death. Special attention was paid to the expression and interaction of the Bcl-2 family of proteins in leukemia cells. The ultimate aim of the study of apoptosis of leukemic cells is the discovery of new biological agents that might be used in the treatment of chronic leukemia.

The role of eosinophilic leukocytes in pathogenesis of bronchial asthma

Pathogenesis of bronchial asthma has not been completely understood. Eosinophilic leukocytes accumulate in high numbers in the lungs, blood and sputum of asthmatic patients. Peripheral blood eosinophilia has been identified as a risk factor for the development of airway obstruction. Prominent eosinophilic inflammatory infiltrate in the bronchial mucosa and correlation between eosinophil numbers and disease severity supports the hypothesis that eosinophils are central inflammatory cells capable of inducing pathophysiological features of asthma. Activated eosinophils secrete a wide range of preformed and newly generated mediators that damage the bronchial epithelium, contract smooth muscle, increase mucous secretion and cause vasodilatation. There is ample evidence that oxidants generation is increased during an asthma exacerbation. Many investigations indicate that airway and blood eosinophils produce more oxidants in asthmatic patients compared with control subjects.