| 1. |
- Borutinskaité, Veronika, et al.
(författare)
-
alpha-Dystrobrevin distribution and association with other proteins in human promyelocytic NB4 cells treated for granulocytic differentiation
- 2011
-
Ingår i: MOLECULAR BIOLOGY REPORTS. - : Springer Science Business Media. - 0301-4851 .- 1573-4978. ; 38:5, s. 3001-3011
-
Tidskriftsartikel (refereegranskat)abstract
- Dystrobrevins (DBs) bind directly to dystrophin and are prominent components of the dystrophin-associated protein complex (DAPC) that links the cytoskeleton to the extracellular matrix. They are involved in brain development, synapse formation and plasticity, as well as water and ion homeostasis. However, the role of DB in non-muscular cells is not clear. In this study, we show that different alpha-dystrobrevin isoforms are present in promyelocytic leukemia (NB4) cells. Only the biggest alpha-dystrobrevin isoform (DB-alpha), which can be important for its function, was expressed in the membrane fraction of NB4 cells; the other alpha-DB isoforms were found in the hydrophilic cell fractions. Employing the immunoprecipitation and mass spectrometry, we identified novel alpha-DB-interacting proteins involved in cytoskeleton reorganization (actin, tropomyosin, gelsolin, tubulin) and signal transduction process (stathmin, prohibitin, RIBA) during proliferation and differentiation of NB4 cells. Our results suggest that alpha-DB isoforms play a central role in cytoskeleton reorganization via their multiple interactions with actin and actin-associating proteins and may participate in signal transduction process during NB4 cell granulocytic differentiation via directly and non directly associated proteins.
|
|
| 2. |
|
|
| 3. |
- Borutinskaite, Veronika Viktorija, 1977-
(författare)
-
Characterization of proteins involved in differentiation and apoptosis of human leukemia and epithelial cancer cells
- 2008
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Today, cancer is understood as an epigenetic as well as a genetic disease. The main epigenetic hallmarks of the cancer cell are DNA methylation and histone modifications. The latter changes may be an optimal target for novel anticancer agents. The main goal of using histone deacetylase inhibitors (HDACIs) would be restoration of gene expression of those tumor-suppressor genes that have been transcriptionally silenced by promoter-associated histone deacetylation. However, HDACIs have pleiotropic effects that we are only just starting to understand. These may also be responsible for the induction of differentiation, cell-cycle arrest and pro-apoptotic effects.There are now so many HDACIs available, with such different chemical structures and biological and biochemical properties, that it is hopeful that at least some of them will succeed, probably in combination with other agents or therapies.In our studies we focussed ourselves on studies some new HDACIs, that can be useful for treating cancers, including leukemia and epithelial cancer. To do that, we used novel HDACIs, like BML-210, and their combination with the differentiation inducer all-trans retinoic acid (ATRA). Cell differentiation and proliferation in general, and specific gene expression require de novo protein synthesis and/or post-translational protein modifications. So, we tried to identify proteins in general and specifically the proteins that could be important for the cell differentiation process, and when and where in the cell the proteins appear.We delineated that HDACIs inhibited leukemia (NB4 and HL-60) cell growth in a time- and dose-dependent way. Moreover, BML-210 blocked HeLa cell growth and promoted apoptosis in a time-dependent way. Combining of BML-210 with ATRA induced a differentiation process in leukemia cell lines that lead to apoptosis. This correlated with cell cycle arrest in G0/G1 stage and changes in expression of cell cycle proteins (p21, p53), transcription factors (NF-κB, Sp1) and their binding activity to consensus or specific promoter sequences. We also assessed histone modifications, i.e. H3 phosphorylation and H4 hyperacetylation due to HDACI, leading to chromatin remodeling and changes in gene transcriptions.We have also studied changes in protein maps caused by HDACIs and differentiation agents, identifying differences for a few proteins due to growth inhibition and induction of differentiation in NB4 cells using BML-210 alone or in combination with ATRA. These proteins are involved in cell proliferation and signal transduction, like Rab, actin and calpain. One of them was alpha-dystrobrevin (α-DB). To further study possible roles of the latter, we determined changes of α-DB protein isoform expression that correlated with induction of differentiation. We thus identified a novel ensemble of α-DB interacting proteins in promyelocytic leukemia cells, including tropomyosin 3, actin, tubulin, RIBA, STAT and others, being important in cytoskeleton reorganization and signal transduction. Using confocal microscopy, we determined that α-DB co-localizes with HSP90 and F-actin in NB4 and HeLa cells. We also revealed that it changes sub-cellular compartment after treatment with ATRA and/or BML-210. α-DB silencing affected F-actin expression in HeLa cells, further supporting the idea that α-DB is involved in cytoskeleton reorganization in cells. Altogether, our results suggest that α−DB may work as a structural protein during proliferation and differentiation processes of human cancer cells.Based on our findings, we suggest that HDACIs, like BML-210, can be promising anticancer agents, especially in leukemia treatment, by inducing apoptosis and regulating proliferation and differentiation through the modulation of histone acetylations and gene expression.
|
|
| 4. |
- Borutinskaite, Veronika V, et al.
(författare)
-
Histone deacetylase inhibitor BML-210 induces growth inhibition and apoptosis and regulates HDAC and DAPC complex expression levels in cervical cancer cells
- 2012
-
Ingår i: Molecular Biology Reports. - : Springer Verlag (Germany). - 0301-4851 .- 1573-4978. ; 39:12, s. 10179-10186
-
Tidskriftsartikel (refereegranskat)abstract
- Histone deacetylase inhibitors (HDACIs) represent a new class of targeted anti-cancer agents and different other diseases, like muscular disorders. A number of studies have shown that extracellular signal-activated kinases can target chromatin-modifying complexes directly and regulate their function. The molecular connection between the dystrophin-associated protein complex (DAPC) and chromatin has been described, by showing that NO signaling regulates histone deacetylase (HDAC) activity and influences gene expression in different cell types. In present study, we investigated HDACs changes in HeLa cells undergoing growth inhibition and apoptosis, caused by HDACI BML-210 and retinoic acid (ATRA). Cell cycle analysis indicated that HeLa cell treatment with 20 and 30 mu M concentration of BML-210 increased the proportion of cells in G0/G1 phase, and caused accumulation in subG1, indicating that the cells are undergoing apoptosis. We determined down-regulation of HDAC 1-5 and 7 after treatment with BML-210. Also, we demonstrated expression of different isoforms of alpha-dystrobrevin (alpha-DB) and other components of DAPC such as syntrophin, dystrophin, beta-dystrobrevin (beta-DB) and NOS in HeLa cells after treatments. We determined changes in protein expression level of dystrophin, NOS1, alpha- and beta-DB and in subcellular localization of alpha-DB after treatments with BML-210 and ATRA. In conclusion, these results suggest that HDACI BML-210 can inhibit cell growth and induce apoptosis in cervical cancer cells, what correlates with down-regulation of HDAC class I and II and changes in the DAPC expression levels. This can be important for identifying target proteins in DAPC signaling to HDACs, as a target of pharmacological intervention for treatment of muscular dystrophies and other diseases.
|
|
| 5. |
|
|
| 6. |
- Khotin, Mikhail, et al.
(författare)
-
Proteomic analysis of ACTN4-interacting proteins reveals its a putative involvement in mRNA metabolism
- 2010
-
Ingår i: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier Science B.V., Amsterdam. - 0006-291X .- 1090-2104. ; 397:2, s. 192-196
-
Tidskriftsartikel (refereegranskat)abstract
- Alpha-actinin 4 (ACTN4) is an actin-binding protein. In the cytoplasm, ACTN4 participates in structural organisation of the cytoskeleton via cross-linking of actin filaments. Nuclear localisation of ACTN4 has also been reported, but no clear role in the nucleus has been established. In this report, we describe the identification of proteins associated with ACTN4 in the nucleus. A combination of two-dimensional gel electrophoresis (2D-GE) and MALDI-TOF mass-spectrometry revealed a large number of ACTN4-bound proteins that are involved in various aspects of mRNA processing and transport. The association of ACTN4 with different ribonucleoproteins suggests that a major function of nuclear ACTN4 may be regulation of mRNA metabolism and signaling.
|
|
| 7. |
- Navakauskiene, Ruta, et al.
(författare)
-
Alpha-Dystrobrevin and its associated proteins in human promyelocytic leukemia cells induced to apoptosis
- 2012
-
Ingår i: Journal of Proteomics. - : Elsevier. - 1874-3919 .- 1876-7737. ; 75:11, s. 3291-3303
-
Tidskriftsartikel (refereegranskat)abstract
- Dystrobrevin is a dystrophin-related component of the dystrophin-associated protein complex (DAPC). Using alpha-dystrobrevin as indicator, we aimed to elucidate the interaction network of the DAPC with other proteins during apoptosis of promyelocytic HL-60 cells. The precise role(s) of DBs are not known, but we and others have shown that they play a role in intracellular signal transduction and cellular organization. Apoptosis was induced with etoposide in the absence or presence of Z-VAD to block caspase activity, and we then followed the cellular distribution of alpha-DB and its association with other proteins, using confocal imaging and cell fractions analyses after immune-precipitation with anti-alpha-DB and mass spectrometry. Confocal imaging revealed distinct spatial relocalizations of alpha-DB between the cell membrane, cytosol and nucleus after induction of apoptosis. The expression levels of the identified proteins were evaluated with computer-assisted image analysis of the gels. We thus identified associations with structural and transport proteins (tropomyosin, myosin), membrane (ADAM21, syntrophin), ER-Golgi (TGN51, eIF38) and nuclear (Lamins, ribonucleoprotein C1/C2) proteins. These results suggest that apoptosis-induction in HL-60 cells involves not only classical markers of apoptosis but also a network alpha-DB-associated proteins at the cell membrane, the cytoplasm and nucleus, affecting key cellular transport processes and cellular structure.
|
|
| 8. |
- Navakauskiene, Ruta, et al.
(författare)
-
Epigenetic changes during hematopoietic cell granulocytic differentiation - comparative analysis of primary CD34+cells, KG1 myeloid cells and mature neutrophils
- 2014
-
Ingår i: BMC Cell Biology. - : BioMed Central. - 1471-2121. ; 15:4
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Epigenetic regulation is known to affect gene expression, and recent research shows that aberrant DNA methylation patterning and histone modifications may play a role in leukemogenesis. In order to highlight the co-operation of epigenetic mechanisms acting during the latter process it is important to clarify their potential as biomarkers of granulocytic differentiation. Results: In this study we investigated epigenetic alterations in human hematopoietic cells at a distinct differentiation stages: primary hematopoietic CD34+ cells, KG1 myeloid leukemic cells, whose development is stopped at early stage of differentiation, and mature neutrophils. We focused on the epigenetic status of cell cycle regulating (p15, p16) and differentiation related (E-cadherin and RAR beta) genes. We found that the methylation level in promoter regions of some of these genes was considerably higher in KG1 cells and lower in CD34+ cells and human neutrophils. As examined and evaluated by computer-assisted methods, histone H3 and H4 modifications, i.e. H3K4Me3, H3K9Ac, H3K9Ac/S10Ph and H4 hyperAc, were similar in CD34+ cells and human mature neutrophils. By contrast, in the KG1 cells, histone H3 and H4 modifications were quite high and increased after induction of granulocytic differentiation with the HDAC inhibitor phenyl butyrate. Conclusions: We found the methylation status of the examined gene promoters and histone modifications to be characteristically associated with the hematopoietic cell progenitor state, induced to differentiate myeloid KG1 cells and normal blood neutrophils. This could be achieved through epigenetic regulation of E-cadherin, p15, p16 and RAR beta genes expression caused by DNA methylation/demethylation, core and linker histones distribution in stem hematopoietic cells, induced to differentiation KG1 cells and mature human neutrophils, as well as the histone modifications H3K4Me3, H3K9Ac, H3K9Ac/S10Ph and H4 hyperAc in relation to hematopoietic cell differentiation to granulocyte. These findings also suggest them as potentially important biomarkers of hematopoietic cell granulocytic differentiation and could be valuable for leukemia induced differentiation therapy.
|
|
| 9. |
- Pivoriunas, Augustas, et al.
(författare)
-
Proteomic Analysis of Stromal Cells Derived from the Dental Pulp of Human Exfoliated Deciduous Teeth
- 2010
-
Ingår i: STEM CELLS AND DEVELOPMENT. - : Mary Ann Leibert. - 1547-3287 .- 1557-8534. ; 19:7, s. 1081-1093
-
Tidskriftsartikel (refereegranskat)abstract
- Human dental pulp derived from exfoliated deciduous teeth has been described as a promising alternative source of multipotent stem cells. While these cells share certain similarities with mesenchymal stem-like cells (MSC) isolated from other tissues, basically they are still poorly characterized. In this study, for the first time, a proteomic map of abundantly expressed proteins in stromal cells derived from the dental pulp of human exfoliated deciduous teeth (SHED) was established. We also analyzed proteomic signatures of 2 clonal strains derived from SHEDs by single-cell cloning. The SHEDs were established from enzyme-disaggregated deciduous dental pulp from 6-year-old children. They had typical fibroblastoid morphology and high colony-forming efficiency index (16.4%). Cloning was performed at the second passage using limiting dilution in a 96-well plate (0.3 cell/well). Differentiation assessment revealed strong osteogenic but no adipogenic potential of the SHEDs in either clonal strain. The cells expressed characteristic antigens of MSC-like cells, including CD73, CD90, CD105, CD146, and did not express hematopoietic markers CD14, CD34, and CD45, as assessed with FACS analysis. For proteomic studies, cytosolic and nuclear proteins were analyzed with 2-dimensional gel electrophoresis (2-DE) and identified using matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF)-mass spectrometry (MS). All proteins were identified with high level of confidence (the lowest sequence coverage was 27%). Identification of highly expressed proteins in SHEDs revealed proteomic profiles very similar to that of MSC-like cells derived from other tissues. We also found a high degree of similarity between proteomic signatures of primary SHEDs and clonal cell strains. Thus, our data confirm a close resemblance between SHEDs and MSC-like cells from other tissues and may serve as starting point for creating-comprehensive proteomic maps.
|
|
| 10. |
- Savickiene, Jurate, et al.
(författare)
-
The histone deacetylase inhibitor FK228 distinctly sensitizes the human leukemia cells to retinoic acid-induced differentiation
- 2006
-
Ingår i: Annals of the New York Academy of Sciences. - : Wiley. - 0077-8923 .- 1749-6632. ; 1091, s. 368-384
-
Tidskriftsartikel (refereegranskat)abstract
- FK228 (depsipeptide) is a novel histone deacetylase inhibitor (HDACI) that has shown therapeutical efficacy in clinical trials for malignant lymphoma. In this article, we examined in vitro effects of FK228 on human leukemia cell lines, NB4 and HL-60. FK228 alone (0.2–1 ng/mL) inhibited leukemia cell growth in a dose-dependent manner and induced death by apoptosis. FK228 had selective differentiating effects on two cell lines when used for 6 h before induction of granulocytic differentiation by retinoic acid (RA) or in combination with RA. These effects were accompanied by a time- and dose-dependent histone H4 hyper-acetylation or histone H3 dephosphorylation and alterations in DNA binding of NF-κB in association with cell death and differentiation. Pifithrin-α (PFT), an inhibitor of p53 transcriptional activity, protected only NB4 cells with functional p53 from FK228-induced apoptosis and did not interfere with antiproliferative activity in p53-negative HL-60 cells. In NB4 cells, PFT inhibited p53 binding to the p21 (Waf1/Cip1) promotor and induced DNA binding of NF-κB leading to enhanced cell survival. Thus, beneficial effects of FK228 on human promyelocytic leukemia may be exerted through the induction of differentiation or apoptosis via histone modification and selective involvement of transcription factors, such as NF-κB and p53.
|
|
