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G-protein Stimulatory ? Subunit Is Involved in Osteogenic Activity in Osteoblastic Cell Line SaOS-2 Cells.

ABSTRACT: In an attempt to study the roles of G-protein stimulatory subunit ? (Gs?) in osteoblasts, we introduced an expression vector encoding Gs? into human osteoblastic cell line SaOS-2, and established the clones stably overexpressing Gs? (SaOS-2-Gs?). In SaOS-2-Gs?, the intracellular content of cyclic AMP (cAMP) was increased compared with the parental SaOS-2 cells. In addition, when treated with PTH[1-34], SaOS-2-Gs? exhibited more accumulation of intracellular cAMP compared with the parental cells, suggesting an increased responsiveness to PTH. We evaluated the proliferation rates of SaOS-2-Gs? and the parental SaOS-2 cells, and found that the proliferation was accelerated in SaOS-2-Gs? cells. Reverse transcription-polymerase chain reaction (RT-PCR) analyses exhibited the increased expression of Runx2, a transcription factor involved in osteoblast differentiation, in SaOS-2-Gs? cells. Finally, to examine the osteoblastic function in vivo, we inoculated SaOS-2-Gs? or parental SaOS-2 cells subcutaneously to immunocompromised nude mice. Although tumors in nude mice were not formed after inoculation of parental SaOS-2 cells, SaOS-2-Gs? cells proliferated in host animals leading to the formation of tumors with mineralized bone-like tissues. Taken together, these results suggest that the signals via Gs? play critical roles in the proliferation and osteogenic functions of osteoblasts.

SUBMITTER: Yamazaki M

PROVIDER: S-EPMC4004849 | biostudies-literature | 2006

REPOSITORIES: biostudies-literature

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G-protein Stimulatory α Subunit Is Involved in Osteogenic Activity in Osteoblastic Cell Line SaOS-2 Cells.

Yamazaki Miwa M Suzuki Akira A Ozono Keiichi K Michigami Toshimi T

Clinical pediatric endocrinology : case reports and clinical investigations : official journal of the Japanese Society for Pediatric Endocrinology 20060429 2

In an attempt to study the roles of G-protein stimulatory subunit α (Gsα) in osteoblasts, we introduced an expression vector encoding Gsα into human osteoblastic cell line SaOS-2, and established the clones stably overexpressing Gsα (SaOS-2-Gsα). In SaOS-2-Gsα, the intracellular content of cyclic AMP (cAMP) was increased compared with the parental SaOS-2 cells. In addition, when treated with PTH[1-34], SaOS-2-Gsα exhibited more accumulation of intracellular cAMP compared with the parental cells, ...[more]

PMID: 24790323

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Dataset Information

G-protein Stimulatory ? Subunit Is Involved in Osteogenic Activity in Osteoblastic Cell Line SaOS-2 Cells.

Publications

G-protein Stimulatory α Subunit Is Involved in Osteogenic Activity in Osteoblastic Cell Line SaOS-2 Cells.

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