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M Malicka-Błaszkiewicz

Publications and source records attributed to M Malicka-Błaszkiewicz.

11 recordsLinked to original sources
PubMed2006

Actin cytoskeleton and beta-actin expression in correlation with higher invasiveness of selected hepatoma Morris 5123 cells.

Our studies were focused on the isolation and characterization of highly motile fraction of cells from hepatoma Morris 5123 population. Cells that underwent several migration cycles through Matrigel - coated filters were successfully cultured. The invasion index was determined by means of Matrigel invasion assay. Statically significant increase in the value of invasion factor for selected cells variant in comparison to the parental population was observed. The considerable changes in the cell shape were followed by the reorganization of the actin cytoskeleton structure including a dense subcortical congestion in the distribution of beta -actin isoform. The visualization of this protein in tumor cells was performed by immunostaining and scanning fluorescent confocal microscopy. The results were confirmed by densitometry analysis of Western blots. In addition, the increased state of actin polymerization in the cytoplasmic fraction of selected cells was determined as measured by filamentous to monomeric (F:G) actin ratio. Concluding, the selected fraction of hepatoma Morris 5123 cells with higher invasion capacity was characterized by rounded shape, remarkable increase of beta -actin level, its submembrane concentration as well as with the increased state of actin polymerization with respect to parental cells population.

Actins↗
PubMed2004

Vanadium(III) complexes with L-cysteine--stability, speciation and the effect on actin in hepatoma Morris 5123 cells.

The complexation processes of vanadium(III) with L-cysteinate and s-methyl-L-cysteinate ligands have been studied in aqueous solutions in the pH range 2-7 by the pH-potentiometric, UV-Vis absorption and CD spectroscopy methods. The equilibria model of complex formation, evaluated by SUPERQUAD program, so as careful inspection of spectroscopic data have allowed to determine the speciation and the coordination mode of vanadium(III) ion in the major species present in aqueous solutions. Relatively stable ML2 species of vanadium(III)-L-cysteinate system exists in aqueous solutions above pH 5. It was deduced from spectral data that the coordination sphere of vanadium(III) ion in V(Cys)2 is completed by oxygen, nitrogen and sulfur atoms of two L-cysteinate ligands. Solution of vanadium(III) with L-cysteine (pH approximately 7, L/M=20) was administrated to the culture medium of hepatoma Morris 5123 growing cells. Cytotoxic effect of this solution towards tumor cells was observed. The viability of these cells depended on the complex concentration. It was reduced by 70% at 100 microM of the vanadium species concentration in the culture medium. The death of cancer cells seems to be induced on apoptotic route. The statistically significant increase of total actin level and filamentous to monomeric actin ratios (F/G) were found in the cytoplasm of cells exposed to the vanadium(III)-L-cysteine complex. It was accompanied by the rearrangement of actin cytoskeleton architecture. These factors are important for migration and metastasis formation of the cancer cells.

Actins↗
PubMed2001

The effect of methotrexate on actin and invasiveness of hepatoma Morris 5123 cells in culture.

Monomeric (G), total (T) and filamentous (F) actin and the state of actin polymerisation (F:G) were determined and actin filaments were visualized in hepatoma Morris 5123 cells cultured in the presence of methotrexate (MTX) at various concentration. The exposure of the cells to this drug resulted in a decrease of total and polymerised actin in cytoplasm and in some changes in actin filament organization. This coincided with a decrease of the cells' ability to migrate through Matrigel coated filters and with inhibition of tumour formation after reimplantation of the methotrexate treated cells to experimental rats.

Actins↗
PubMed1999

Identification of actin from hepatoma Morris 5123 cells.

The hepatoma Morris 5123 tumor growth is accompanied by changes in actin content and polymerization (Malicka-Błaszkiewicz et al. (1995) Mat. Med. Pol., 27, 115-118; Nowak et al. (1995) J. Exp. Cancer Res. 14, 37-40). Presently actin isoforms from cytosol and cytoskeleton fractions were separated by SDS/PAGE and identified with antibodies directed against different actin isoforms. Actin isolated from the cytosol by affinity chromatography on DNase I bound to agarose shows the presence of only one protein spot on 2D gel electrophoresis corresponding to the mobility of the rabbit a skeletal muscle actin (Mr 43,000) and isoelectric point equal to 5.3. It interacts only with monoclonal anti beta actin isoform antibodies, posing the question of differential affinity of actin isoforms to DNase I.

Actins↗
PubMed1986

DNase I-like activity and actin content in the liver of some vertebrates.

Total actin content and F:G actin ratio were determined in the liver cytosol of fish, frogs and mouse by measurements of inhibition of exogenous crystalline bovine pancreatic DNase I. Endogenous DNase I-like activity, was found in all examined livers after electrophoresis in the presence of sodium dodecyl sulfate and subsequent enzyme renaturation. It is concluded that DNase I-like enzymes occur in the liver cytosol in a latent form, probably bound to cytoplasmic actin.

Actins↗
PubMed1979

Partial purification and some properties of a liver alkaline ribonuclease from the frog Rana esculenta.

1. RNAases varying in pH optimum, activation with pCMB, sensitivity towards temperature and acid treatment, as well as electrophoretic mobility were found in Rana esculenta liver extract. 2. Of the three activity peaks of alkaline ribonuclease separated on CM-cellulose with 2000-fold purification, RNAase of peak C is thermo- and acid-stable and exhibits specificity for pyrimidine bases, preferring poly(U) over poly(C). 3. Differences in the specific "inhibitory effect" of frog liver supernatant on the frog liver alkaline RNAase were observed.

Animals↗
PubMed1978

Acid phosphatase from liver of the frog Rana esculenta, separation and partial characterization of multiple forms.

1. Acid phosphatase (AcPase) from liver of the frog, Rana esculenta has been isolated and purified. The enzyme is heterogeneous, showing 4 activity zones on disc electrophoresis. The AcPase was separated into 3 peaks on DEAE-cellulose. Peak A corresponding to the electrophoretic AcPase IV represents an extensively purified enzyme form. 2. The separated enzyme forms are change isomers with a molecular weight of about 33,000. They differ markedly in substrate requirements and sensitivity towards activators and inhibitors. All of them are highly activated by dithiothreitol, show a rather restricted substrate specificity, and marked activity against ATP.

Acid Phosphatase↗
PubMedDate not supplied

Rat liver DNase I-like activity and its interaction with actin.

Monomeric G actin, total actin and the F:G actin ratio were determined in the rat liver cytosol and nucleoplasm by measuring the inhibition of standard crystalline DNase I. Actin was purified from rat liver nucleoplasm by Sephadex filtration. Accompanying the considerable amount of actin an endogenous DNase I like activity was found in rat liver cytosol and nucleoplasm. It was shown, that similarly to DNase I from bovine pancreas the liver DNase was inhibited by mammalian and avian skeletal muscle actin as well as by endogenous liver actin, as verified by electrophoresis of DNase containing extracts on polyacrylamide gels with incorporated DNA.

Actins↗
PubMedDate not supplied

The RNAse-RNAse inhibitor system in the liver of the frog Rana esculenta: subcellular distribution and differential binding of inhibitor with multiple RNAses.

The aim of our work was to investigate the biological basis of the existence of multiple alkaline RNAses in the Rana esculenta liver with respect to formation of a RNAse-RNAse inhibitor complex (latent RNAse). Subcellular distribution indicated that most of the alkaline RNAse activity appeared in the high-speed supernatant and mainly in a latent form bound to an endogenous inhibitor. This RNAse-RNAse inhibitor complex was isolated, the bound RNAse activity was released and found to correspond to RNAse III and RNAse IV, the two most cathodic RNAses present in the supernatant fraction. The two RNAses differed markedly in the ability to interact with the inhibitor and this might be essential for the different biological roles the RNAses may play in the regulation of cytoplasmic RNA level. On the basis of molecular weight determinations we assume that the enzyme-inhibitor complex is shared by two different RNAses.

Animals↗
PubMedDate not supplied

Actin content and polymerization in tumour, liver and serum of the hepatoma Morris 5123 tumour bearing rats.

Monomeric G-actin, total actin and filamentous F-actin were examined during the growth of experimental tumour hepatoma Morris 5123. Actin was measured by the inhibition of the standard DNase I from bovine pancreas. A remarkable increase in total actin, and F-actin content, as well as in the state of actin polymerization (measured by the F:G actin ratio) was shown in the cytosol of the tumour cells in the second week of the tumour growth, followed by a rapid decrease in the third week. Parallel observations were made in the cytosol of the liver and in the serum of the tumour bearing rats. The results were compared with the data obtained for control healthy rats. It was shown that hepatoma Morris tumour growth is accompanied by the changes in the actin content and polymerization, occurring also in the liver of the host animal. Only G-actin was found in the serum. It increased significantly in the second week of tumour growth as compared with the G-actin level in the serum of the control healthy rats.

Actins↗