Glycogen phosphorylase BB as a potential marker of cardiac toxicity in patients treated with anthracyclines for acute leukemia.

Objectives: The aim of the presented study was to assess plasma glycogen phosphorylase BB (GPBB) concentrations in acute leukemia patients treated with anthracycline containing chemotherapy.
Background: Anthracyclines represent the highest risk for development of cardiotoxicity. GPBB belongs to proposed biomarkers of cardiac injury with a very limited experience in this context.
Methods: Totally, 24 adult patients with acute leukemia were enrolled. Plasma GPBB concentrations were measured by ELISA at diagnosis (before chemotherapy), after first chemotherapy with anthracyclines and 6 months after the completion of treatment. The cut-off value for GPBB positivity was 10.00 µg/L as recommended by the manufacturer.
Results: Before chemotherapy, the mean plasma GPBB concentration was 5.25±3.81 µg/L, increased above the cut-off in 1 patient (4.2 %). After the first chemotherapy, the mean GPBB was 6.61±5.54 µg/L, positive in 7 (29.2 %) patients. Six months after treatment, the mean GPBB was 10.06±11.41 µg/L, positive in 8 (33.3 %) patients. Six months after treatment, we found a significant correlation between elevation in GPBB and diastolic left ventricular dysfunction on echocardiography (r=0.621; p<0.0001). The differences in plasma GPBB between healthy blood donors and patients treated for acute leukemia were statistically significant (p<0.01 in all cases).
Conclusion: Our results suggested that GPBB could become a potential biomarker for detection of acute and chronic cardiotoxicity associated with anthracycline containing chemotherapy. The predictive value for development of treatment-related cardiomyopathy in future is not clear and will be evaluated during the follow-up. Further studies are needed to define the potential role of GPBB and other biomarkers in the assessment of chemotherapy-induced cardiotoxicity (Ref. 21). Text in PDF www.elis.sk.