The Effect of Telomerase Template Antagonist GRN163L on Bone-Marrow-Derived Rat Mesenchymal Stem Cells is Reversible and Associated with Altered Expression of Cyclin d1, cdk4 and cdk6

Abstract

Telomerase activity is essential for the continued growth and survival of malignant cells, therefore inhibition of this activity presents an attractive target for anti-cancer therapy. The telomerase inhibitor GRN163L, was shown to inhibit the growth of cancer cells both in vitro and in vivo. Mesenchymal stem cells (MSCs) also show telomerase activity in maintaining their self-renewal; therefore the effects of telomerase inhibitors on MSCs may be an issue of concern. MSCs are multipotent cells and are important for the homeostasis of the organism. In this study, we sought to demonstrate in vitro effects of GRN163L on rat MSCs. When MSCs were treated with 1 µM GRN163L, their phenotype changed from spindle-shaped cells to rounded ones and detached from the plate surface, similar to cancer cells. Quantitative-RT-PCR and immunoblotting results revealed that GRN163L holds MSCs at the G1 state of the cell cycle, with a drastic decrease in mRNA and protein levels of cyclin D1 and its cdk counterparts, cdk4 and cdk6. This effect was not observed when MSCs were treated with a mismatch control oligonucleotide. One week after GRN163L was removed, mRNA and protein expressions of the genes, as well as the phenotype of MSCs returned to those of untreated cells. Therefore, we concluded that GRN163L does not interfere with the self-renewal and differentiation of MSCs under short term in vitro culture conditions. Our study provides additional support for treating cancers by administrating GRN163L without depleting the body's stem cell pools.

Poly (hydroxyethyl methacrylate-glycidyl methacrylate) films modified with different functional groups: In vitro interactions with platelets and rat stem cells

“…Bone marrow derived MSCs were isolated from rats. Consistent with previous observations by us and others [49][50][51], the cells were positive for mesenchymal stem cell markers such as CD90, CD71, and CD29, and negative for hematopoietic cell lineage markers such as CD34 and CD45 shown by RT-PCR (Fig. 5A).…”

Patterned carbon nanotubes as a new three-dimensional scaffold for mesenchymal stem cells

“…3). Consistent with previous observations by us and others [27,28], our results showed that MSCs were positive for the expression of MSC markers (CD90, CD71 and CD29) but negative for hematopoietic stem cell markers (CD45 and CD34) for all passages as expected at the transcript level (Fig. 3a).…”

“…4c) and viability (Fig. 5) on collagen coated or non-coated patterned CNTs than in early passage (P0) can be explained by the aging of MSCs [27,38,39]. Gruber et al have shown that the mean percent senescence increased significantly with cell passaging [38] and high passage numbers adversely affected the functioning of stem cells [39].…”

Preparation and characterization of poly(hydroxyethyl methacrylate-co -poly(ethyleneglycol-methacrylate)/hydroxypropyl-chitosan) hydrogel films: Adhesion of rat mesenchymal stem cells

“…In the previous studies, chitosan containing interpenetration network has been used as an adsorbent for separation of protein from aqueous medium due to its high contents of amino and hydroxyl functional groups. 45,46 The PEG side-chains onto copolymer membranes can be expected to reduce the interaction between blood (plasma protein and cells) and the membrane surface. As expected, PEG side-chains containing membranes showed reduced platelet adhesion compared to pHEMA, and p(HEMA-HPC)-1-2, and p(HEMA-PEG-MA-HPC) formulations.…”