Abstract: The present invention is directed to isolated nucleic acid molecules encoding gamma glutamyl hydrolase (GH). Expression vectors and host cells comprising the nucleic acid molecules are also provided, as well as methods for increasing or decreasing the expression of GH in host cells. The invention further provides a method of screening a substance for the ability of the substance to modify GH function, and a method for isolating other GH molecules. DNA oligomers and antibodies specific for GH are provided, each of which can be used to detect GH in a sample. Methods for decreasing deleterious side effects of antifolate treatment, increasing the levels of GH in cells of a patient, increasing the effectiveness of antifolate treatment, and monitoring progression of a tumor are further provided.

Abstract: The present invention is directed to isolated nucleic acid molecules encoding gamma glutamyl hydrolase (GH). Expression vectors and host cells comprising the nucleic acid molecules are also provided, as well as methods for increasing or decreasing the expression of GH in host cells. The invention further provides a method of screening a substance for the ability of the substance to modify GH function, and a method for isolating other GH molecules. DNA oligomers and antibodies specific for GH are provided, each of which can be used to detect GH in a sample. Methods for decreasing deleterious side effects of antifolate treatment, increasing the levels of GH in cells of a patient, increasing the effectiveness of antifolate treatment, and monitoring progression of a tumor are further provided.