Gene expression patterns of osteocyte-like MLO-Y4 cells in response to cyclic compressive force stimulation.

Although osteocytes have long been regarded as mechanosensors for translating mechanical signals into biochemical signals to regulate the other bone cells, the global gene expression patterns and pathways of osteocytes responding to mechanical stimulation are not well defined. We investigated CCF (cyclic compressive force) responsive gene expression patterns at different time-points using Mouse genome-wide oligonucleotide microarrays with an osteocyte-like MLO-Y4 cell model. We performed a SOM (self-organizing maps) clustering algorithm based on pattern similarity to organize clusters of temporal expression patterns, and used qRT-PCR (quantitative reverse transcriptase PCR) analysis to validate expression patterns of selected genes. We also used functional and pathway analysis to evaluate the biological features of the data. In this study, we derived a biological hypothesis from the gene expression profiles that CCF triggers a tightly regulated transcriptional programme to induce bone resorption cell signalling and involves common pathways in osteocytes.