Disruption of gap junctional intercellular communication in human renal cancer cell lines.
OBJECTIVE
Gap junctional intercellular communication (GJIC) is believed to play an important role in the maintenance of cell homeostasis, and its disruption may be associated with carcinogenesis. However, GJIC has not been detected in many human cancers. We therefore studied the regulation of GJIC in human renal cancer cell lines.


METHODS
We examined the human renal cancer cell lines, ACHN and NT, as well as Madin-Darby canine kidney (MDCK) cells as a positive control, using GJIC assays, Northern blotting to detect connexin 43 mRNA, immunofluorescent staining, and Western blotting of connexin 43 protein.


RESULTS
GJIC of ACHN and NT was completely blocked. In ACHN cells, connexin 43 mRNA was not altered. However, connexin 43 protein was aberrantly localized and phosphorylated connexin 43 protein had disappeared. Both connexin 43 protein and its mRNA were undetectable in NT cells.


CONCLUSIONS
GJIC in human renal cancer cell lines is impaired and various pathways may inhibit this mechanism in renal cancer. We believe that connexin plays an important role in renal carcinogenesis.
Noguchi
M
M
Department of Urology, Nagasaki University School of Medicine, Japan.
Nomata
K
K
Watanabe
J I
JI
Sato
H
H
Kanetake
H
H
Saito
Y
Y
D002292:Carcinoma, Renal Cell / Q000378:metabolism / Q000648:ultrastructure*; D018031:Connexin 43 / Q000096:biosynthesis; D017629:Gap Junctions; D006801:Humans; D007680:Kidney Neoplasms / Q000378:metabolism / Q000648:ultrastructure; D012313:RNA / Q000032:analysis; D014407:Tumor Cells, Cultured
D018031:Connexin 43; D012313:RNA