Plasma biomarkers reflecting high oxidative stress in the prediction of myocardial injury due to anthracycline chemotherapy and the effect of carvedilol: insights from the CECCY Trial

Background: Anthracycline (ANT) is often used for breast cancer treatment but its clinical use is limited by cardiotoxicity (CTX). CECCY trial demonstrated that the β-blocker carvedilol (CVD) could attenuate myocardial injury secondary to ANT. Mieloperoxydase (MPO) is a biomarker of oxidative stress and galectin-3 (Gal-3) is a biomarker of fibrosis and cardiac remodeling. We evaluated the correlation between MPO and Gal-3 behavior with CTX. Materials and Methods: A post hoc analysis was performed in the patients who were included in the CECCY trial. A total of 192 women had her blood samples stored during the study at –80°C until the time of assay in a single batch. Stored blood samples were obtained at baseline, 3 and 6 months after randomization. We excluded samples from 18 patients because of hemolysis. MPO and Gal-3 were measured using Luminex xMAP technology through MILLIPLEX MAP KIT (Merck Laboratories). Results: 26 patients (14.9%) had a decrease of at least 10% in LVEF at 6 months after the initiation of chemotherapy. Among these, there was no significant difference in the MPO and Gal-3 when compared to the group without drop in LVEF (p = 0.85 for both MPO and Gal-3). Blood levels of MPO [baseline: 13.2 (7.9, 24.8), 3 months: 17.7 (11.1, 31.1), 6 months: 19.2 (11.1, 37.8) ng/mL] and Gal-3 [baseline: 6.3 (5.2, 9.6), 3 months: 12.3 (9.8, 16.0), 6 months: 10.3 (8.2, 13.1) ng/mL] increased after ANT chemotherapy, and the longitudinal changes were similar between the placebo and CVD groups (p for interaction: 0.28 and 0.32, respectively). In an exploratory analysis, as there is no normal cutoff value established for Gal-3 and MPO in the literature, the MPO and Gal-3 results were splited in two groups: above and below median. In the placebo group, women with high (above median) baseline MPO blood levels demonstrated a greater increase in TnI blood levels than those with low baseline MPO blood levels (p = 0.041). Compared with placebo, CVD significantly reduced TnI blood levels in women with high MPO blood levels (p < 0.001), but did not reduce the TnI levels in women with low baseline MPO blood levels (p = 0.97; p for interaction = 0.009). There was no significant interaction between CVD treatment and baseline Gal-3 blood levels (p for interaction = 0.99). Conclusions: In this subanalysis of the CECCY trial, MPO and Gal-3 biomarkers did not predict the development of CTX. However, MPO blood levels above median was associated with more severe myocardial injury and identified women who were most likely to benefit from carvedilol for primary prevention (NCT01724450).