Serum levels of N2, N2-dimethylguanosine and pseudouridine as determined by radioimmunoassay for patients with malignancy.

A sensitive, rapid, and specific radioimmunoassay procedure was used to determine levels of N2,N2-dimethylguanosine and pseudouridine in sera of patients with acute leukemia and breast cancer. Elevated levels of both nucleosides were above standard deviations of the normal mean for patients in both disease categories.