Restor Dent Endod.  2012 Aug;37(3):142-148. 10.5395/rde.2012.37.3.142.

Analysis of gene expression during odontogenic differentiation of cultured human dental pulp cells

• Seo MS
• Hwang KG
• Kim H
• Baek SH

• KMID: 1995653
• DOI: http://doi.org/10.5395/rde.2012.37.3.142

Abstract

OBJECTIVES
We analyzed gene-expression profiles after 14 day odontogenic induction of human dental pulp cells (DPCs) using a DNA microarray and sought candidate genes possibly associated with mineralization.
MATERIALS AND METHODS
Induced human dental pulp cells were obtained by culturing DPCs in odontogenic induction medium (OM) for 14 day. Cells exposed to normal culture medium were used as controls. Total RNA was extracted from cells and analyzed by microarray analysis and the key results were confirmed selectively by reverse-transcriptase polymerase chain reaction (RT-PCR). We also performed a gene set enrichment analysis (GSEA) of the microarray data.
RESULTS
Six hundred and five genes among the 47,320 probes on the BeadChip differed by a factor of more than two-fold in the induced cells. Of these, 217 genes were upregulated, and 388 were down-regulated. GSEA revealed that in the induced cells, genes implicated in Apoptosis and Signaling by wingless MMTV integration (Wnt) were significantly upregulated.
CONCLUSIONS
Genes implicated in Apoptosis and Signaling by Wnt are highly connected to the differentiation of dental pulp cells into odontoblast.

Keyword

Differentiation; Gene set enrichment analysis; Human dental pulp cell; Microarray

MeSH Terms

Apoptosis
Dental Pulp
Gene Expression
Genes, vif
Humans
Microarray Analysis
Odontoblasts
Oligonucleotide Array Sequence Analysis
Polymerase Chain Reaction
RNA
RNA

Figure

• 

  Figure 1 (a) Left: Dishes of control (non-induced) DPCs, Right: induced (OM-treated) DPCs after Alizarin-Red staining; (b) The expression of surface markers as analyzed by flow cytometry of control and induced DPCs. Left: control DPCs. Right: induced DPCs. Q3 means cells exhibits negative to STRO-1 and CD146 antibody. DPC, dental pulp cell; OM, odontogenic induction medium.

• 

  Figure 2 Gene set enrichment analysis (GSEA) identifying novel pathways activated in odontogenic inducted cells relative to the control cells.

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