Tissue-specific expression of Na,K-ATPase β-subunit Does β2 expression correlate with tumorigenesis?

We have found a substantial decrease in the level of Na,K-ATPase β2-subunit mRNA in xenografts of human renal, lung hepatocellular carcinomas in nude mice as compared with corresponding normal tissues, as well as in the neuroblastoma cell line as compared with the neuron primary cell culture. The level of β1 mRNA is decreased in kidney and lung tumor cells, but is unchanged in hepatocellular carcinoma. In the neuroblastoma cell line the level of β1 subunit mRNA was found to be higher then in neuron primary cell culture. The level of α1 mRNA in investigated tumors was the same as in normal tissues. These results may give evidence of the involvement of β2-subunit in the process of tumorigenesis as was shown for some other adhesion molecules.