The correlation of serum immunoglobulin free light chain levels and selected biological markers in multiple myeloma.
ABSTRACT the presented study is aimed at the evaluation of correlation of free light chains serum levels - kappa, lambda and their relation (K/L ratio) and serum levels of selected biological markers in a group of patients with multiple myeloma examined at the time of the diagnosis.
102 patients with multiple myeloma were included in this prospective study. Free light chains serum levels were determined by Freelite Binding Site system, for determination of serum levels of selected parameters the following methods were used: REA thymidinekinase (TK), RIA (beta(2)microglobulin (beta(2)m), ICTP, PINP), enzymoimmunoassay (sIL-6R, sVCAM-1, sICAM-1, sOPG) and quantitative enzymatic immunoassay (sHGF, sVEGF, sSyndecan-1 (sSyn-1) a sFas).
There was found a correlation in the kappa-group of the dominant kappa chain and serum readings of beta(2)m (r = 0.344, p = 0.005), TK (r = 0.263, p = 0.035), ICTP (r = 0.402, p = 0.001), PINP (r = 0.264, p = 0.039), sOPG (r = 0.328, p = 0.028), sSyn-1 (r = 0.255, p = 0.046) and sFas (r = 0.418, p = 0.001). In case of K/L ratio there was found a statistically significant association of levels of beta(2)m (r = 0.316, p = 0.01), TK (r = 0.274, p = 0.027), ICTP (r = 0.346, p = 0.006), PINP (r = 0.261, p = 0.042), sSyn-1 (r = 0.283, p = 0.026) and sFas (r = 0.377, p = 0.002). In the lambda-group the analysis confirmed mutual dependence of the dominant lambda chain levels on beta(2)m (r = 0.476, p = 0.003), ICTP (r = 0.375, p = 0.022), sVCAM-1 (r = 0.383, p = 0.019), sHGF (r = 0.441, p = 0.006) and sFas (r = 0.334, p = 0.040). In addition we ascertained a correlation of L/K ratio and levels of beta(2)m (r = -0.473, p = 0.003), TK (r = -0.412, p = 0.011), ICTP (r = -0.331, p = 0.045), PINP (r = -0.409, p = 0.012), sHGF (r = -0.357, p = 0.028), sSyn-1 (r = -0.449, p = 0.005) a sFas (r = - 0.371, p = 0.022).
The study confirmed mutual correlation of FLC serum levels and the levels of several selected biological markers, in particular beta(2)m, TK, ICTP, PINP, sSyn-1 a sFas at time of the diagnosis. It referred to the mutual relation of bone marrow microenvironment, biological qualities of clonal plasmocytes and the intensity of the free light chains production by the tumour cell population.
Full-textDOI: · Available from: Jiri Minarik, May 28, 2015
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ABSTRACT: PurposeQuantitative mass spectrometry assays for immunoglobulins (Igs) are compared with existing clinical methods in samples from patients with plasma cell dyscrasias, e.g. multiple myeloma.Experimental designUsing LC-MS/MS data, Ig constant region peptides and transitions were selected for liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MRM). Quantitative assays were used to assess Igs in serum from 83 patients.ResultsLC-MRM assays quantify serum levels of Igs and their isoforms (IgG1–4, IgA1–2, IgM, IgD, and IgE, as well as kappa (κ) and lambda (λ) light chains). LC-MRM quantification has been applied to single samples from a patient cohort and a longitudinal study of an IgE patient undergoing treatment, to enable comparison with existing clinical methods. Proof-of-concept data for defining and monitoring variable region peptides are provided using the H929 multiple myeloma cell line and two MM patients.Conclusions and Clinical RelevanceLC-MRM assays targeting constant region peptides determine the type and isoform of the involved immunoglobulin and quantify its expression; the LC-MRM approach has improved sensitivity compared with the current clinical method, but slightly higher interassay variability. Detection of variable region peptides is a promising way to improve Ig quantification, which could produce a dramatic increase in sensitivity over existing methods, and could further complement current clinical techniques.This article is protected by copyright. All rights reservedPROTEOMICS - CLINICAL APPLICATIONS 04/2014; 8(9-10). DOI:10.1002/prca.201300077 · 2.68 Impact Factor