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Tallinn, Estonia

Methods of stimulating multipotency, proliferation and differentiation of isolated mesenchymal stem cells (MSCs), which permit more effective differentiation and integration of such cells into host tissues. The method includes providing an in vitro cell population of MSCs and administering CCL5 chemokine. Preferably CCL is administered in an amount sufficient to induce expression of one or more multipotency related genes selected from the group consisting of OCT3/4, NANOG, SOX 2, KLF4, and SOX9.

Tints K.,Protobios LLC | Prink M.,Protobios LLC | Prink M.,Competence Center for Cancer Research | Neuman T.,Protobios LLC | And 2 more authors.
International Journal of Molecular Sciences | Year: 2014

Degenerate expression of transcription coregulator proteins is observed in most human cancers. Therefore, in targeted anti-cancer therapy development, intervention at the level of cancer-specific transcription is of high interest. The steroid receptor coactivator-1 (SRC-1) is highly expressed in breast, endometrial, and prostate cancer. It is present in various transcription complexes, including those containing nuclear hormone receptors. We examined the effects of a peptide that contains the LXXLL-motif of the human SRC-1 nuclear receptor box 1 linked to the cell-penetrating transportan 10 (TP10), hereafter referred to as TP10-SRC1LXXLL, on proliferation and estrogen-mediated transcription of breast cancer cells in vitro. Our data show that TP10-SRC1LXXLL induced dose-dependent cell death of breast cancer cells, and that this effect was not affected by estrogen receptor (ER) status. Surprisingly TP10-SRC1LXXLL severely reduced the viability and proliferation of hormone-unresponsive breast cancer MDA-MB-231 cells. In addition, the regulation of the endogenous ERα direct target gene pS2 was not affected by TP10-SRC1LXXLL in estrogen-stimulated MCF-7 cells. Dermal fibroblasts were similarly affected by treatment with higher concentrations of TP10-SRC1LXXLL and this effect was significantly delayed. These results suggest that the TP10-SRC1LXXLL peptide may be an effective drug candidate in the treatment of cancers with minimal therapeutic options, for example ER-negative tumors. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

Kazantseva J.,Protobios LLC | Kazantseva J.,Cellin Technology LLC | Palm K.,Protobios LLC | Palm K.,Tallinn University of Technology
International Journal of Molecular Sciences | Year: 2014

Development is a highly controlled process of cell proliferation and differentiation driven by mechanisms of dynamic gene regulation. Specific DNA binding factors for establishing cell- and tissue-specific transcriptional programs have been characterised in different cell and animal models. However, much less is known about the role of “core transcription machinery” during cell differentiation, given that general transcription factors and their spatiotemporally patterned activity govern different aspects of cell function. In this review, we focus on the role of TATA-box associated factor 4 (TAF4) and its functional isoforms generated by alternative splicing in controlling lineage-specific differentiation of normal mesenchymal stem cells and cancer stem cells. In the light of our recent findings, induction, control and maintenance of cell differentiation status implies diversification of the transcription initiation apparatus orchestrated by alternative splicing. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

Jaager K.,Tallinn University of Technology | Jaager K.,Cellin Technologies LLC | Islam S.,Karolinska Institutet | Zajac P.,Karolinska Institutet | And 3 more authors.
PLoS ONE | Year: 2012

Background: Tissue regeneration and recovery in the adult body depends on self-renewal and differentiation of stem and progenitor cells. Mesenchymal stem cells (MSCs) that have the ability to differentiate into various cell types, have been isolated from the stromal fraction of virtually all tissues. However, little is known about the true identity of MSCs. MSC populations exhibit great tissue-, location- and patient-specific variation in gene expression and are heterogeneous in cell composition. Methodology/Principal Findings: Our aim was to analyze the dynamics of differentiation of two closely related stromal cell types, adipose tissue-derived MSCs (AdMSCs) and dermal fibroblasts (FBs) along adipogenic, osteogenic and chondrogenic lineages using multiplex RNA-seq technology. We found that undifferentiated donor-matched AdMSCs and FBs are distinct populations that stay different upon differentiation into adipocytes, osteoblasts and chondrocytes. The changes in lineage-specific gene expression occur early in differentiation and persist over time in both AdMSCs and FBs. Further, AdMSCs and FBs exhibit similar dynamics of adipogenic and osteogenic differentiation but different dynamics of chondrogenic differentiation. Conclusions/Significance: Our findings suggest that stromal stem cells including AdMSCs and dermal FBs exploit different molecular mechanisms of differentiation to reach a common cell fate. The early mechanisms of differentiation are lineage-specific and are similar for adipogenic and osteogenic differentiation but are distinct for chondrogenic differentiation between AdMSCs and FBs. © 2012 Jääger et al.

Jaager K.,Tallinn University of Technology | Jaager K.,Cellin Technologies LLC | Fatkina A.,Cellin Technologies LLC | Velts A.,Cellin Technologies LLC | And 3 more authors.
Gene | Year: 2014

Mesenchymal stem cells (MSCs) possess a multi-lineage differentiation capacity that makes them important players in the field of regenerative medicine. MSC populations derived from different tissues or donors have been shown to exhibit variable gene expression patterns. Further, it is widely acknowledged that MSC isolates are heterogeneous mixtures of cells at different developmental stages. However, the heterogeneity of expression of lineage regulators has not been linked to differentiation potential of different MSC populations towards mesenchymal lineages. Here, we analyzed variation of expression of differentiation markers across whole population and between single differentiating cells of multipotent stromal cell populations derived from adipose tissue (AdMSCs) and skin (FBs) of seven donors. The results of the analyses show that all cell populations exhibit similar differentiation potential towards adipocyte, osteoblast and chondrocyte lineages despite tissue type- and donor-specific variations of expression of differentiation-associated genes. Further, we detected variable expression of lineage regulators in individual differentiating cells. Together, our data indicate that single cells of stromal cell populations could use distinct molecular mechanisms to reach a common cell fate. © 2013 Elsevier B.V.

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