Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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Transcription profiling of mouse chondrocytes treated with MEK/ERK pathway inhibitors

ABSTRACT: Objectives: To identify similarities and differences in gene expression data in the MEK/ERK and PI3K pathways and to determine how histone modification affects these same pathways. Goal: To identify and functionally characterize novel targets of these signaling pathways in the context of chondrocyte differentiation. Experiment Overall Design: Cartilage derived from the hind limbs of CD1 mice staged at 15.5 days of embryonic development were dissected and plated in primary chondrocyte monolayer cultures. Cells were treated with MEK/ERK pathway inhibitors (SB202190 and UO126), a PI3K inhibitor (LY294002), a histone deacetylase inhibitor (Trichostatin A) and the vehicle control (DMSO) for 24 hours. Total RNA was isolated from these samples and hybridized to Affymetrix MOE 430 2.0 chips at the London Regional Genomics facility. Experiment Overall Design: A total of 15 genechips were analyzed between 4 treatments and the vehicle (DMSO) control. Three biological replicates per treatment were executed. Experiment Overall Design: Experiment Overall Design:

ORGANISM(S): Mus musculus

SUBMITTER: veronica ulici

PROVIDER: E-GEOD-15069 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Project description:Autologous chondrocyte transplantation (ACT) is a routine technique to regenerate focal cartilage lesions. However, patients with osteoarthritis (OA) are lacking an appropriate long-lasting treatment alternative, partly since it is not known if chondrocytes from OA patients have the same chondrogenic differentiation potential as chondrocytes from donors not affected by OA. Articular chondrocytes from patients with OA undergoing total knee replacement (Mankin Score >3, AhlbÃ¤ck Score >2) and from patients undergoing ACT, here referred to as normal donors (ND), were isolated applying protocols used for ACT. Their chondrogenic differentiation potential was evaluated both in high-density pellet and scaffold (Hyaff-11) cultures by histological proteoglycan assessment (Bern Score) and immunohistochemistry for collagen types I and II. Chondrocytes cultured in monolayer and scaffolds were subjected to gene expression profiling using genome-wide oligonucleotide microarrays. Expression data were verified by using quantitative RT-PCR. Chondrocytes from ND and OA donors demonstrated accumulation of comparable amounts of cartilage matrix components, including sulphated proteoglycans and collagen types I and II. The mRNA expression of cartilage markers (COL2A1, COMP, aggrecan, CRTL1, SOX9) and genes involved in matrix synthesis (biglycan, COL9A2, COL11A1, TIMP4, CILP2) was highly induced in 3D cultures of chondrocytes from both donor groups. Genes associated with hypertrophic or OA cartilage (COL10A1, RUNX2, periostin, ALP, PTHR1, MMP13, COL1A1, COL3A1) were not significantly regulated between the two groups of donors. The expression of 661 genes, including COMP, FN1, and SOX9, were differentially regulated between OA and ND chondrocytes cultured in monolayer. During scaffold culture, the differences diminished between the OA and ND chondrocytes, and only 184 genes were differentially regulated. Only few genes were differentially expressed between OA and ND chondrocytes in Hyaff-11 culture. The risk of differentiation into hypertrophic cartilage does not seem to be increased for OA chondrocytes. Our findings suggest that the chondrogenic capacity is not significantly affected by OA and OA chondrocytes fulfill the requirements for matrix-associated ACT. Experiment Overall Design: Gene expression profiles of monolayer cultures (ML; passage 2) and Hyaff-11 scaffold cultures (3D; 14 days in vitro) of chondrocytes from 3 normal donors (ND; underwent ACT treatment) and 3 donors suffering from Osteoarthritis (OA; underwent knee replacement surgery) were determined. Comparative analyses between 3D and ML cultures (3D vs. ML) were performed to assess differentiation capacity of ND and OA chondrocytes. Furthermore, OA-related differences were determined comparing OA and ND monolayers as well as scaffold cultures (each OA vs. ND).

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Transcription profiling of mouse chondrocytes treated with MEK/ERK pathway inhibitors

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