Ionic regulation of proliferation in normal and cancer cells

The use of electron probe X-ray microanalysis (EPXMA) in association with appropriate cell and tissue preparative procedures has allowed several laboratories to measure the intracellular levels of a number of ions during mitogenesis. It has been possible to study changes in the ionic concentration of normal, preneoplastic, and overtly neoplastic cells for determining the stage of involvement of ionic changes during carcinogenesis. A demonstration of such preneoplastic changes in ionic concentration could provide the basis for differential diagnosis of cancer by EPXMA and could ultimately provide a basis for rational cancer chemotherapeutic intervention. The use of EPXMA in association with appropriate cell and tissue preparative procedures has allowed several laboratories to measure and to test Cone's prediction that the intracellular levels of Na + are changed in rapidly dividing and overt tumor cells as compared to slowly dividing or nondividing normal cells. An advantage of such a microprobe procedure is that quantitative data can be simultaneously obtained on several elements in a single analysis.