[Clinical observation on the changes in plasma cyclic nucleotides in patients with leukemia before and after treatment and their relation to cell-mediated immunity].

ABSTRACT

UNLABELLED Level of plasma cyclic nucleotides was determined in 47 normal subjects and 63 patients with leukemia. Follow-up was carried out in 20 of these patients. The relation between the level of cyclic nucleotides and cell-mediated immunity was studied. THE RESULTS: There was no significant difference in cyclic adenosine monophosphate (cAMP) between the normal subjects and leukemic patients, whereas cyclic guanosine monophosphate (cGMP) level was markedly elevated and cAMP/cGMP ratio was obviously reduced in the untreated and unrelieved patients. There was no significant difference in the various types of leukemia. In patients with complete remission (CR) after treatment, their cyclic nucleotides were similar to those in normal subjects, but they remained abnormal in patients without clinical remission after treatment. In CR patients treated regularly for half a year, the cGMP level when first diagnosed was lower than that of patients who died soon or were unrelieved. Plasma cGMP level was negatively correlated to E-rosette forming cell (E-RFC) and cAMP/cGMP ratio was positively correlated to E-RFC. These results suggest that the plasma cGMP be used as additional parameter to monitor the treatment response and prognosis. Reduced E-RFC in leukemia may be related to the elevated cGMP and/or lowered cAMP/cGMP ratio.