ISSN:
0730-2312
Keywords:
osteosarcomas
;
adenylate cyclase
;
phospholipase C
;
G-proteins
;
growth rate
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Previously, it has been shown that the GTP-binding protein Gi2 is implicated in cellular growth [1,2] and differentiation [2,3]. In the present paper we demonstrate that this is also the case for human sarcoma cells.Six human osteosarcoma and three soft tissue sarcoma clonal cell lines were analyzed for levels of G-protein mRNA and polypeptide expression and effector enzyme (i.e., adenylate cyclase and phospholipase C) activation, which were all compared with individual growth rates. Unexpectedly, it appeared that the various strains exhibited large inter-individual variations in G-protein expression and signaling system activation. However, cell doubling time in the exponential phase of growth was inversely correlated (r = 0.71, P 〈 0.05) to immunodetected levels of intrinsic Gi2α. Furthermore, cells stably transfected with a retroviral (pZipNeo(SV)X) construct containing the activating or inactivating Gi2α-R179E or Gi2α-G204A point mutations consistently reduced or enhanced individual cell strain doubling time, respectively.It appeared that other parameters investigated, including cellular alkaline phosphatase and monoclonal antibody epitope binding, both being markers of the proliferating osteoblast, did not correlate with cell doubling times. © 1996 Wiley-Liss, Inc.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
