This proposal embraces possible connections between oncogenes and ion transport. It has long been known that tumor cells, unlike normal cells, can grow in calcium-deficient media. This difference may be explained by a new finding -- a calcium- and phorbol-inhibitable, bumetanide-resistant potassium-efflux pathway. In untransformed mouse NIH-3T3 cells, the efflux pathway opens when cells are in calcium-deficient media, and closes on addition of calcium or an active phorbol. In SV40-transformed NIH-3T3 cells, the efflux pathway is nearly closed in high or low calcium media. Studies are planned on possible modifiers of this efflux pathway, and will include changes in intracellular pH or cyclic AMP levels, and addition of channel blockers. A variety of oncogene- transformed NIH-3T3 cells will be tested to see if any show the same phenotypic properties of SV40-transformed NIH-3T3 cells: ability to grow in calcium-deficient media, and a nearly closed potassium-efflux pathway.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA047382-02
Application #
3191009
Study Section
Cellular Biology and Physiology Subcommittee 1 (CBY)
Project Start
1988-04-01
Project End
1991-03-31
Budget Start
1989-04-01
Budget End
1990-03-31
Support Year
2
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Dartmouth College
Department
Type
Schools of Medicine
DUNS #
041027822
City
Hanover
State
NH
Country
United States
Zip Code
03755
Lubin, M (1993) An impurity in phenol red opens an ion channel in cultured human cells. In Vitro Cell Dev Biol Anim 29A:597-600