The present study was to evaluate whether activities of serum acid polyribonucleotide hydrolases could be used for diagnostic and therapeutic markers for leukemia. Activities of acid polyribonucleotide hydrolases using polycytidylate (poly C), polyuridylate (poly U), polyadenylate (poly A), polyguanylate (poly G) and RNA as substrate were measured in serum of patients with acute lymphocytic leukemia (ALL) and myelogenous leukemia (AML) before and after combined chemotherapy. DEAE-cellulose column chromatographical analyses for acid polyribonucleotide hydrolases in leukemic serum were carried out to find out the enzymes specific to leukemia. ,
1. Of acid polyribonucleotide hydrolases studied, the activities of poly C, poly U and RNA hydrolases were significantly increased in serum of both ALL and AML and the positive rates of these enzyme activities were high enough to be used as diagnostic markers. The degree of increment in the activity and the positive rate of the enzyme activity exhibited the highest value for AML with acid poly C hydrolase.
2. In 6 cases out of 9 cases of ALL studied in the present work, the activity of acid poly C hydrolase was decreased toward the normal control value following the intensive chemotherapeutic measures against ALL.
3. A DEAE-cellulose column chromatographic analyses showed that acid poly C, poly U and RNA hydrolases in serum of leukemia were seperated into 3 to 4 peaks, respectively, of which peak IV acid poly U hydrolase appeared to be specific to AML.
The results indicated that acid poly C hydrolase activity was singificantly increased in serum of both ALL and AML and that the serum enzyme could be used as a diagnostic marker for both ALL and AML and a therapeutic marker for ALL.
Also observed was the presence of acid polyribonucleotide hydrolases in multiple form in leukemic serum and suggested was the appearance of a poly U hydrolase specific to AML.
|