NBT-II carcinoma behaviour is not dependent on cell-cell communication through gap junctions.
To study the mechanism(s) underlying the proliferation of heterogeneous cell populations within a solid tumour, the NBT-II rat bladder carcinoma system was used. It has been first investigated whether the different cell populations are coupled through gap junctions (GJIC). Cells overexpressing the Cx43 were generated to test for any tumour suppressive activity in vivo. To determine whether GJIC is essential for tumour proliferation and the establishment of a cooperative community effect, NBT-II cells that are incompetent for cell coupling were generated. The data report that (i) carcinoma cells expressing or not FGF-1 are coupled through GJIC in vitro and in coculture and express the gap junction protein Cx43, (ii) overexpression of Cx43 in these cells does not affect their in vitro coupling capacities and in vivo tumourigenic growth properties, (iii) inhibition of GJIC through antisense strategy has no in vivo obvious consequence on the tumour growth properties of the carcinoma, and (iv) the community effect between two carcinoma cell populations does not critically involve cell coupling through gap junctions.
Lesueur
F
F
Genetic and Cancer Susceptibility Unit, IARC, 150 Cours Albert Thomas, 69372 Lyon Cedex, France.
Mesnil
M
M
Delouvée
A
A
Girault
J M
JM
Yamasaki
H
H
Thiery
J P
JP
Jouanneau
J
J
D000818:Animals; D015152:Blotting, Northern; D002450:Cell Communication; D002455:Cell Division; D002471:Cell Transformation, Neoplastic; D018920:Coculture Techniques; D018031:Connexin 43 / Q000096:biosynthesis; D016220:Fibroblast Growth Factor 1 / Q000096:biosynthesis; D017629:Gap Junctions / Q000502:physiology*; D051379:Mice; D008819:Mice, Nude; D051381:Rats; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000473:pathology*
D018031:Connexin 43; D016220:Fibroblast Growth Factor 1