Kang HB, Kim YE, Kwon HJ, Sok DE, Lee Y.. Enhancement of NF-kappaB expression and activity upon differentiation of human embryonic stem cell line SNUhES3. Stem Cells Dev 16: 615-623

Department of Biochemistry, College of Natural Sciences, Chungbuk National University, Cheongju, Chungbuk, 361-763, Korea.
Stem Cells and Development (Impact Factor: 3.73). 09/2007; 16(4):615-23. DOI: 10.1089/scd.2007.0014
Source: PubMed


NF-kappaB is involved in many biological processes including proliferation, survival, and differentiation. Because human embryonic stem (ES) cells have the potential to differentiate to various lineages, understanding mechanisms involved in stemness and lineage differentiation is an important issue. We investigated expression of NF-kappaB in the human ES cell lines SNUhES3 and MizhES4 and found that expression of NF-kappaB mRNA and protein in these two cell lines was significantly lower compared to those of other adult cell lines. However, when SNUhES3 cells were induced to differentiate by retinoic acid, expression levels of NF-kappaB significantly increased compared to undifferentiated SNUhES3 cells. As the components of tumor necrosis factor-alpha (TNF-alpha) signaling are expressed comparably in undifferentiated and differentiated SNUhES3 cells, we examined the responsiveness of SNUhES3 cells to treatment with TNF-alpha, an agonist of NF-kappaB signaling. Nuclear localization of NF-kappaB in response to TNF-alpha was evident in differentiated, but not undifferentiated, SNUhES3 cells. In agreement with this observation, induction of interleukin-8 (IL-8) in response to TNF-alpha was seen only in differentiated SNUhES3 cells. On the basis of an IkappaB kinase (IKK) inhibitor study, expression of IL-8 induced by TNF-alpha was dependent on NF-kappaB activity. Taken together, our results suggest that expression and activity of NF-kappaB is comparatively low in undifferentiated human ES cells, but increases during differentiation of the ES cells.

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    • "Results are of three experiments, each conducted in duplicate. determine the relative amount of immunoprecipitated DNA from the PAD4 promoter region, the IL8 promoter region with which p50 and p65 are known to interact with as a positive control, and the negative control C4ORF11 (Fig. 5; Kang et al., 2007). ChIP analysis confirmed that p65 was highly enriched at the IL8 promoter but not significantly enriched at the PAD4 promoter upon TNF-α stimulation (Fig. 5A, B). "
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    Gene 10/2013; 533(1). DOI:10.1016/j.gene.2013.09.108 · 2.14 Impact Factor
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    Cytokine 03/2013; 62(1). DOI:10.1016/j.cyto.2013.01.021 · 2.66 Impact Factor
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    • "It has been shown that expression of NFκB significantly increased following differentiation of embryonic stem (ES) cells with retinoic acid. Additionally, nuclear localization of NFκB in response to TNFα, an agonist of NFκB signaling, was evident in differentiated, but not in undifferentiated ES cells [25]. Similar results have been obtained by other authors [7]. "
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