High levels of interleukin-6 are associated with low tumor burden and low
growth fraction in multiple myeloma
OF Ballester, LC Moscinski, GH Lyman, JV Chaney, HI Saba, AS Spiers and C Klein
Division of Bone Marrow Transplantation, H. Lee Moffitt Cancer Center,
Tampa, FL 33612-9497.
Interleukin-6 (IL-6) is a multifunctional cytokine postulated to play a
central role as a growth factor for multiple myeloma (MM). We evaluated the
spontaneous secretion of IL-6 in supernatants of Ficoll-Hypaque-- enriched
bone marrow (BM) cultures from 35 patients with MM. The levels of IL-6 were
correlated with biological and clinical characteristics of the disease.
High levels of IL-6 production defined a subgroup of patients with low
tumor burden as determined by lower serum beta 2- microglobulin (B2M) (P =
.02) and lower percentage of myeloma cells infiltrating the bone marrow (P
= .003), higher synthetic rates of monoclonal protein (P = .006), and low
proliferative compartments as measured by the percentage of Ki-67--positive
myeloma cells. Patients with high proliferative fractions (Ki-67--positive
myeloma cells > 20%) had significantly lower levels of IL-6 when
compared with patients with low proliferative fractions (P = .005). Our
findings do not support IL- 6 as a major growth factor for MM, but
demonstrate an association of high levels of IL-6 secretion with low tumor
cell burden and low proliferative fraction.
Volume 83,
Issue 7,
pp. 1903-1908,
04/01/1994
Copyright © 1994 by The American Society of Hematology
