Mannan-binding lectin (MBL) and MBL-associated serine protease-2 in children with cancer

QUESTIONS UNDER STUDY: Mannan-binding lectin (MBL) and MBL-associated serine protease-2 (MASP-2) are two key components of the lectin-pathway of complement-activation. Information on the potential role of lectin-pathway components in carcinogenesis versus immune surveillance of cancer is scarce. This study aimed to determine if serum concentrations of MBL and MASP-2 differ between children with cancer and healthy age-matched controls. METHODS: In this retrospective multicentre study, MBL and MASP-2 were measured by commercially available ELISA in frozen remnants of serum taken at diagnosis in paediatric patients with cancer. For six diagnostic groups, these concentrations were compared with serum concentrations of age-matched healthy controls using exact Wilcoxon signed-rank tests. RESULTS: MBL and MASP-2 were measured in serum of 372 patients. MBL was significantly higher in patients with solid tumours vs. controls (median, 2,799 vs. 1,917 mu g/L; P = 0.008), and MASP-2 was significantly higher in patients with acute lymphoblastic leukaemia (406 vs. 317 mu g/L; P = 0.009), Non-Hodgkin lymphoma (361 vs. 293 mu g/L; P = 0.037) and CNS tumors (463 vs. 296 mu g/L; P = 0.002). CONCLUSIONS: These results may indicate a role of MBL and MASP-2 in the initiation or progression of specific paediatric cancers, while other mechanisms remain possible as well. Larger, disease-specific studies are warranted for confirmation and for elucidation of the underlying mechanisms.