Potential use of serum CD44 as an indicator of tumour progression in acuteleukemia

CD44 is a widely expressed cell surface glycoprotein with various functions . This molecule is shed from the cell surface and released as a soluble mol ecule. High serum levels of CD44 have been demonstrated in some solid tumou rs. In this study we measured serum CD44 in 25 patients with acute leukemia , in 12 with bacterial infections, and in 13 normal controls. The levels of serum CD44 of patients with bacterial infections were significantly higher (mean 531.3+/-60.1 ng/ml, p<0.001) than those of normal controls (299.0+/- 115.4ng/ml). Acute leukemia patients before treatment had almost four-fold higher levels of serum CD44 than normal controls (mean 1301.9+/-1384.6 ng/m l, p<0.01). Serum CD44 levels were correlated with clinical status. After t reatment the serum CD44 levels significantly decreased, but they were still higher than in normal controls. Patients in complete remission all relapse d if serum CD44 levels were higher than 500 ng/ml (normaI+2 SD) after chemo therapy. The serum CD44 levels were correlated with the absolute numbers of leukemic cells in peripheral blood. The results demonstrated that serum CD 44 levels correlate well with the clinical status of acute leukemia, and su ch evaluation may provide a reliable tumour marker of acute leukemia. Copyr ight (C) 1999 John Wiley & Sons, Ltd.