Circadian variations of interleukin-2 receptors, serum thymidine kinase and beta-2-microglobulin in patients with non-Hodgkin's lymphoma and normal controls

In this study we investigated whether circadian rhythms of interleukin-2 receptors (sIL-2R), serum thymidine kinase (sTK) and beta-2-microglobulin (beta 2M) are apparent, which may influence tumor marker detection. Blood was drawn every two hours over 24 hours from 6 patients with NHL, 3 healthy donors and three patients with non-hematologic disorders. The serum levels of the three markers were measured. The three normal volunteers showed circadian variations of sIL-2R sTK and beta 2M best described by a sinusoidal curve. This rhythm could also be demonstrated in three of the six patients with NHL for all three markers. In three patients the circadian rhythm of one marker was disturbed. The three NHL-patients with consistent circadian rhythms in all three markers achieved a complete remission whereas the patients with disturbed rhythm progressed under therapy. We showed that circadian variations of sIL-2R, sTK and beta 2M follow a sinusoidal circadian rhythm in normals and patients with NHL. Disturbance of this rhythm may be related to a worse prognosis.