Correction: Human Adipose Tissue-Derived Mesenchymal Stem Cells Target Brain Tumor-Initiating Cells

<p>Correction: Human Adipose Tissue-Derived Mesenchymal Stem Cells Target Brain Tumor-Initiating Cells</p

mRNA expression of cyto-chemokine receptors in human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) after co-culture with brain tumor-initiating cells (BTICs).

<p>Real-time Quantitative Polymerase Chain Reaction (RT-qPCR) analysis of cyto-chemokine receptors after co-culture of (A) medulloblastoma-BTICs, (B) atypical teratoid/rhabdoid tumors (AT/RT)-BTICs and (C) glioblastoma-BTICs. The mRNA level of each cytokine receptor was normalized to the level of GAPDH. All data are representative of three independent experiments, and each value represents the mean ± SD. *Significant difference from control (P < 0.05).</p

Induced cytokine levels in the BTICs after co-cultured with HFF1 or hAT-MSCs (pg/ml)^*.

<p>BTICs: brain tumor initiating cells, HFF1: human foreskin fibroblast, hAT-MSCs: human adipose-derived mesenchymal stem cells, AT/RT: atypical teratoid rhabdoid tumor, MCP-1: monocyte chemoattractant protein 1, SDF-1: stromal cell-derived factor 1, RANTES: regulated on activation, normal T cell expressed and secreted, IL-6: interleukin-6 ligand, IL-8: interleukin-8, IGF-1: insulin-like growth factor 1ligand, PDGF-bb: platelet-derived growth factor, VEGF: vascular endothelial growth factor, Ang-1: angiopoietin1</p><p>*[induced cytokine level in the BTICs with HFF1] = [total cytokine level in the BTICs with HFF1]-[cytokine level in the HFF1 only]</p><p>[induced cytokine level in the BTICs with hAT-MSCs] = [total cytokine level in the BTICs with hAT-MSCs]-[cytokine level in the hAT-MSCs only]</p><p>Induced cytokine levels in the BTICs after co-cultured with HFF1 or hAT-MSCs (pg/ml)^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0129292#t001fn002" target="_blank">*</a>}.</p

Knock down of cytokine receptors on hAT-MSCs.

<p>After siRNAs treatment to each cytokine receptors on hAT-MSCs, (A) the protein expressions were confirmed in hAT-MSCs by western blot and (B) the migratory ability toward BTICs is assessed using trans-well assay. (C) The quantified results show inhibition of migration by selective knock down of cytokine receptors. ×50 magnification. All data are representative of three independent experiments, and each value represents the mean ± SD. *P < 0.05, **P < 0.01, ***P < 0.001.</p

Migratory ability of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) toward brain tumor-initiating cells (BTICs) <i>in vivo</i>.

<p>Fluorescence images of the brains were taken at the indicated times. (A) In the absence of tumor, the fluorescent signals of hAT-MSCs (blue) are weakened at 2 weeks and are not detectable at 3 weeks. (B) <i>In vivo</i> sequential tracking was performed by injecting both NEO-LIVE 675-labeled BTICs (red) and NEO-LIVE 797-labeled hAT-MSCs (blue). hAT-MSCs gradually migrate toward the tumor site, and strong fluorescent signals are observed at 4 weeks post-injection at the tumor site. (C) Mice were injected the NEO-LIVE 797-labeled hAT-MSCs or HFF1. Representative <i>in vivo</i> fluorescence images show that the HFF1 signals are decreased or fade out. (D) On the contrary, the hAT-MSC signals are widened at all BTIC-derived mouse brain tumor sites at 3 weeks post-injection when compared with HFF1 cells. The color bar indicates radiant efficiency.</p