ABSTRACT
<p><b>OBJECTIVE</b>To explore the functional effects of MAPK pathway in the pathogenesis of human osteosarcoma.</p><p><b>METHODS</b>Gene microarray (Human Genome U133A, Affymetrix) was used to screen the differential expression of genes involved in MAPK pathway between osteosarcoma cell lines and 3 osteoblastic cell lines. KEGG metabolic pathway analysis was performed among significantly increased or decreased genes using the MATLAB software. Immunohistochemical technique was used to detect the expressions of ERK1/2, JNK and p38 proteins among 48 osteosarcoma and benign 24 osteoblastic tumor samples.</p><p><b>RESULTS</b>Using an entrance limit of > or = 2.0, 18 differentially expressed MAPK pathway-related genes were selected (10 up-regulated, 8 down-regulated) to mapped to the MAPK pathway of KEGG which are all important node genes. The positive rates of ERK1/2, JNK and p38 proteins were 83.3% (40/48), 72.9% (35/48) and 85.4% (41/48) in osteosarcomas,and 12.5% (3/24), 8.3% (2/24) and 16.7% (4/24) in the control group, respectively. The positive rates and expression intensities were statistically different between the 2 groups (P<0.01).</p><p><b>CONCLUSION</b>MAPK pathway plays an important role in the pathogenesis of osteosarcoma. ERK, JNK and p38 form an intercoordinating network and regulate the cell proliferation, differentiation, apoptosis, invasion and migration in osteosarcoma.</p>
Subject(s)
Adolescent , Adult , Aged , Child , Female , Humans , Male , Middle Aged , Young Adult , Bone Neoplasms , Genetics , Metabolism , Pathology , Cell Line, Tumor , Gene Expression Profiling , JNK Mitogen-Activated Protein Kinases , Metabolism , Mitogen-Activated Protein Kinase 1 , Metabolism , Mitogen-Activated Protein Kinase 3 , Metabolism , Mitogen-Activated Protein Kinases , Metabolism , Oligonucleotide Array Sequence Analysis , Osteoblastoma , Genetics , Metabolism , Pathology , Osteosarcoma , Genetics , Metabolism , Pathology , Signal Transduction , p38 Mitogen-Activated Protein Kinases , MetabolismABSTRACT
Objective:To screen for the pathogenesis-related genes of osteosarcoma and to assess their roles for the de- velopment of osteosareoma.Methods:Total RNA was extracted from 3 ATCC osteosarcoma cell lines and an osteoblastic cell line and was used to synthesize biotinylated cRNAs;the latter were hybridized to Affymetrix~(?)GeneChip~(?)U133A ar- rays and a gene with more than 2 folds of change was selected.Ten of the differentially expressed genes were chosen and the primers were designed and the synthesized.Then SYBR~(?)Green real-time PCR(RT-PCR)method was used to detect the expression of the 10 genes in 9 fresh osteosarcoma specimens.ABI Prism 7 000 system was used to analyze the differ- ent expression between osteosarcoma cell line and osteoblastic cell line.Results:We identified 58 up-regulated and 142 down-regulated genes in the 3 osteosareoma cell lines.Many of the genes were firstly reported to be related to the patho- genesis of osteosarcoma.These differentially expressed genes were mainly involved in energy and material metabolism,on- cogene,signal transduction gene,transcription- related genes,cell cycle-related genes,cell apoptosis-related gene,im- mune response gene,tumor suppressor genes,etc.The array results of 10 randomly selected genes were further verified by the RT-PCR in 9 fresh osteosarcoma specimens.Conclusion:Many genes are involved in the pathogenesis of osteosarcoma. Gene microarray can help to discover the genes related to the pathogenesis of osteosarcoma,which may lay a foundation for studying the molecular mechanism of osteosarcom.