Role of hyaluronidase in the regulation of hemopoiesis

Implication of JAK1, JAK2, and JAK3 in the Realization of Proliferation and Differentiation Potential of Mesenchymal Progenitor Cells In Vitro

Involvement of individual JAK kinases in the realization of growth potential of mesenchymal progenitor cells was examined in vitro. Important role of JAK2 and JAK3 in determining the initial level of mitotic activity of progenitor cells was established. The yield of fibroblast CFUF was suppressed under the effect of specific inhibitors of JAK kinases. Blockade of JAK3 increased the rate of progenitor element differentiation. JAK1 had no effect on proliferation and differentiation status of progenitor cells.

Role of JNK and Involvement of p53 in Stimulation of Growth Potential Realization of Mesenchymal Precursor Cells by Alkaloid Songorine

The role of JNK-mediated signal pathway and participation of p53 transcription factor in stimulation of realization of the growth potential of the mesenchymal precursor cells by alkaloid songorine were examined in vitro. Specific inhibitors of JNK and p53 enhanced stimulation of fibroblast colony/cluster formation and proliferative activity of mesenchymal precursor cells. Under these conditions, more pronounced effects were observed with early precursors of fibroblast CFU and in both cases were accompanied by a decrease in differentiation index of progenitor elements.

Role of cAMP- and IKK-2-Dependent Signaling Pathways in Functional Stimulation of Mesenchymal Progenitor Cells with Alkaloid Songorine

The role of cAMP- and IKK-2-dependent pathways in stimulation of the growth capacity of mesenchymal progenitor cells with alkaloid songorine was studied in vitro. Inhibitors of adenylate cyclase and IKK-2 were shown to abolish the increase in proliferative activity of progenitor cells. Moreover, blockade of the inhibitory kinase complex was accompanied by a decrease in the intensity of progenitor cell differentiation.

Involvement of cAMP- and IKK-2-dependent signal pathways in the growth capacity of mesenchymal progenitor cells under the influence of basic fibroblast growth factor

We studied the role of cAMP- and IKK-2-dependent pathways under conditions of functional stimulation of mesenchymal progenitor cells by basic fibroblast growth factor. An adenylate cyclase inhibitor 2',5'-dideoxyadenosine had no effect on functional activity of early (primitive) mesenchymal precursors. This agent produced a stimulatory effect on proliferation of stromal precursor cells. Mitotic activity of mesenchymal progenitor cells was shown to decrease after treatment with a specific blocker of the IKK-2 kinase-inhibitor complex.

Extracellular matrix macromolecules: potential tools and targets in cancer gene therapy

Tumour cells create their own microenvironment where they closely interact with a variety of soluble and non-soluble molecules, different cells and numerous other components within the extracellular matrix (ECM). Interaction between tumour cells and the ECM is bidirectional leading to either progression or inhibition of tumourigenesis. Therefore, development of novel therapies targeted primarily to tumour microenvironment (TME) is highly rational. Here, we give a short overview of different macromolecules of the ECM and introduce mechanisms whereby they contribute to tumourigenesis within the TME. Furthermore, we present examples of individual ECM macromolecules as regulators of cell behaviour during tumourigenesis. Finally, we focus on novel strategies of using ECM macromolecules as tools or targets in cancer gene therapy in the future.

Effect of pegylated hyaluronate-endo-β-N-acetylhexosaminidase on humoral mechanisms regulating the functions of progenitor cells during chronic hepatitis

We studied the effect of hyaluronate-endo-β-N-acetylhexosaminidase on the secretory function of the liver and bone marrow microenvironment cells in chronic hepatitis. Enhanced production of substances stimulating parenchymal tissue-specific precursors and stem cell homing factors by liver cells was revealed. At the same time, production of SDF-1 and other chemoattractants and adhesion factors of progenitor cells by bone marrow elements was reduced.

Humoral mechanisms regulating the functions of progenitor cells in chronic hepatitis

We studied the secretory function of the liver and bone marrow microenvironment cells under conditions of chronic CCl4-induced hepatitis. Enhanced production of substances stimulating parenchymal tissue-specific precursors and stem cell homing factors by liver cells was observed. In situ binding of stem cells by bone marrow elements increased due to production of various cooperation and adhesion factors against the background of reduced SDF-1 secretion.