Aberrant expression, function and localization of connexins in human esophageal carcinoma cell lines with different degrees of tumorigenicity.
We have analyzed the level of mRNA expression and protein localization of the gap-junction protein connexins (Cx) 26, 32, and 43, as well as gap-junctional intercellular communication (GJIC) in seven human esophageal carcinoma cell lines (TE series). These cell lines exhibited various degrees of tumorigenicity in nude mice; two (TE-1 and TE-8) formed progressively growing tumors, four (TE-2, TE-3, TE-9, and TE-13) developed non-progressing tumors and one (TE-10) showed no tumorigenicity. We found that normal human esophageal tissue expressed both Cx26 and Cx43 and that most of the cell lines expressed lower amounts of Cx26 and Cx43 mRNAs than normal human esophageal tissues or none at all. The co-expression of Cx26 and Cx43 mRNAs and proteins was observed only in two cell lines (TE-3 and TE-9) that showed a high level of GJIC and non-progressive tumor development. However, the non-tumorigenic cell line TE-10 did not express either connexin. A possible regulator of GJIC, E-cadherin, was expressed in all cell lines. These results suggest that aberrant expression and function of connexins are common among human esophageal carcinoma cell lines, but there is no quantitative relationship between connexin expression and tumorigenic properties of these cell lines.
Oyamada
Y
Y
International Agency for Research on Cancer, Lyon, France.
Oyamada
M
M
Fusco
A
A
Yamasaki
H
H
D000818:Animals; D015139:Blotting, Southern; D015153:Blotting, Western; D015820:Cadherins / Q000378:metabolism; D000072259:Connexin 26; D018031:Connexin 43 / Q000032:analysis / Q000235:genetics / Q000502:physiology; D017630:Connexins / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D004938:Esophageal Neoplasms / Q000378:metabolism* / Q000473:pathology; D004947:Esophagus / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D012333:RNA, Messenger / Q000032:analysis; D014183:Transplantation, Heterologous; D014407:Tumor Cells, Cultured; D000097002:Gap Junction beta-1 Protein
D015820:Cadherins; D000072259:Connexin 26; D018031:Connexin 43; D017630:Connexins; D012333:RNA, Messenger; D000097002:Gap Junction beta-1 Protein; C000607042:GJB2 protein, human