Differences in the expression of connexin genes in rat hepatomas in vivo and in vitro

摘要: Gap-junctional intercellular communication (GJIC) in normal rat liver cells involves at least three different connexins (Cxs)--Cx32, Cx26, Cx43--depending on the cell type, position lobule, or both. Whereas hepatocyte primary cultures expressed Cx32 and Cx26 as observed vivo, lines derived from (WB-F344, Clone 9, RLEC, BRL) Cx43 to a lesser extent Cx26. Hepatoma propagated vitro were either deficient GJIC Cx expression (7777, 8994, H4IIE-C3) communicated via gap junctions composed of protein (N1S1-67, 9618A). Analysis neoplasms that resulted injection hepatoma into femoral muscle showed differences when compared with grown vitro. 7777 H4IIE-C3 failed express mRNAs culture, these transplanted vivo levels mRNA comparable those liver. However, detectable immunostaining was less than 5% neoplastic vivo. These results indicate posttranscriptionally downregulated tumor cells. Unexpectedly, 9618A culture but In contrast, N1S1 transplants continued Unlike punctate staining suspension cells, diffuse intracellular N1S1-derived although electrophoretic pattern isolated tumors (43 kDa) 45 kDa). Thus, findings reported here demonstrate depends environment, whether vitro, which are propagated.