The differential effects of IL-1 and TNF-alpha on proinflammatory cytokine and matrix metalloproteinase expression in human chondrosarcoma cells.
OBJECTIVE
Interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF-alpha), and matrix metalloproteinases (MMPs) play important roles in the pathogenesis of osteoarthritis (OA). In the present study, using Affymetrix oligonucleotide array technology and real-time quantitative RT-PCR we have investigated the molecular mechanisms underlying the differential effect of IL-1 and TNF-alpha on gene expression in the human chondrosarcoma cell line, SW1353.


METHODS
SW1353 cells were stimulated singularly with IL-1alpha, TNF-alpha, Phorbol 12-myristate 13-acetate (PMA), or treated with the combination of cytokine and PMA. Total RNA was collected at multiple time points over a 24-h period followed by biotinylated cRNA target preparation and hybridization onto the Affymetrix HG-U95Av2 array. The differential expression patterns of several cytokine and MMP genes were further confirmed by real time quantitative RT-PCR, Western blot, and ELISA.


RESULTS
Our microarray experiments have broadly confirmed previously published data on chondrocyte gene expression regulated by IL-1 and TNF-alpha. The expression pattern of proIL-1beta, MMP-1, and MMP-13 in chondrocytes is differentially regulated when stimulated with proinflammatory cytokines. IL-1, but not TNF-alpha, can induce IL-6, bone morphogenic protein 2 (BMP-2), and cyclooxygenase (COX-2) expression in SW1353 cells. Additionally, our Western blot results provide the first evidence that IL-1beta is produced in the proform in IL-1alpha-activated chondrosarcoma cells and that additional signals are required for its posttranslational processing/activation.


CONCLUSIONS
IL-1 and TNF-alpha each activate a distinct set of genes in chondrosarcoma cells, and gene expression in these cells is regulated by groups of genes related in part by their function. Chondrocyte IL-1alpha appears to serve an important role in the pathogenesis OA contributing to joint inflammation and cartilage destruction.
Department of Antibacterial, Immunology, and Inflammation, Pfizer Global Research and Development, Groton, CT 06340, USA.
J
J
Shi
E
E
Schmitt-Talbot
D A
DA
DiMattia
R G
RG
Dullea
D045744:Cell Line, Tumor; D002813:Chondrosarcoma / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D016000:Cluster Analysis; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics*; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D007249:Inflammation / Q000235:genetics / Q000378:metabolism; D018836:Inflammation Mediators / Q000097:blood / Q000378:metabolism; D007375:Interleukin-1 / Q000096:biosynthesis / Q000494:pharmacology*; D020782:Matrix Metalloproteinases / Q000096:biosynthesis / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D011994:Recombinant Proteins / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D016207:Cytokines; D018836:Inflammation Mediators; D007375:Interleukin-1; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D020782:Matrix Metalloproteinases; D013755:Tetradecanoylphorbol Acetate