Bone marrow mast cell density correlates with serum levels of VEGF and CXC chemokines ENA-78 and GRO-α in multiple myeloma.

Angiogenesis is a crucial process in growth and progression of multiple myeloma (MM). Mast cells (MCs) play an important role in MM angiogenesis. Various angiogenic mediators secreted by MCs regulate endothelial cell proliferation and function. Among them, ELR(+) CXC chemokines, such as growth-related oncogen-alpha (GRO-α) and epithelial neutrophil activating protein-78 (ENA-78), have been described as potential mediators in regulation of angiogenesis. The purpose of the study was to quantify MCs in bone marrow (BM) biopsies of MM patients, expressed as MC density (MCD), and correlate it with serum concentrations of vascular endothelial factor (VEGF), GRO-α, ENA-78. Fifty-four newly diagnosed MM patients and 22 healthy controls were studied. Tryptase was used for the immunohistochemical stain of MCs. VEGF, GRO-α, and ENA-78 were measured in sera by ELISA. MCD and serum levels of GRO-α, ENA-78, and VEGF were significantly higher in MM patients compared to controls (p<0.001 in all cases). MCD was significantly increasing with increased stage of the disease (p<0.001). Furthermore, significant correlations were found between MCD with VEGF, GRO-α, and ENA-78. These findings support that MCs participate in the pathophysiology of MM and is implicated in the angiogenic process and disease progression.

Lack of correlation between angiogenic cytokines and serum insulin-like growth factor-1 in patients with multiple myeloma.

There are many growth factors influencing the expansion of multiple myeloma (MM). Angiogenesis is a process that may enhance MM growth, in various manners. Among them, insulin-like growth factor-1 (IGF-1) is a major factor, acting in many levels. The aim of the study was to measure serum levels of IGF-1 in newly diagnosed MM patients and to correlate them with clinical stage of the disease and with markers of angiogenesis, such as vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and interleukin-6 and 15 (IL-6 and IL-15). Serum levels of the above factors were measured, by ELISA, in 57 newly diagnosed MM patients and in 20 healthy controls. There was no difference in serum levels of IGF-1 in MM patients and in controls, contrary to angiogenic factors, which were higher in MM patients (p < 0.001). Similarly, IGF-1 did not correlate with clinical stage of the disease nor the other angiogenic factors, which also correlated with each other (p < 0.001). Serum IGF-1 concentrations are not influenced in MM patients. Therefore, although it is a proliferation cytokine, it cannot be used as marker of disease activity.

Angiogenesis-related cytokines, RANKL, and osteoprotegerin in multiple myeloma patients in relation to clinical features and response to treatment.

An essential cytokine system for the osteoclast biology in multiple myeloma (MM) consists of the receptor of activator of NF-κB ligand (RANKL), its receptor (RANK), and the soluble decoy receptor, osteoprotegerin (OPG). Myeloma cells cause imbalance in OPG/RANKL interactions. We measured serum levels of OPG, soluble (s) RANKL, sRANKL/OPG ratio, markers of disease activity [LDH, CRP, interleukin-6 (IL-6), ß2-microglobulin (B2M)], and angiogenic factors [hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF)], in 54 newly diagnosed MM patients and in 25 of them in plateau phase. All the above values were higher in MM patients compared to controls and decreased in plateau phase. sRANKL and RANKL/OPG were higher with advancing disease stage and skeletal grade. Significant correlations were found among RANKL and RANKL/OPG with HGF, LDH, VEGF, IL-6, and B2M. In conclusion, RANKL and OPG play significant roles in MM pathophysiology, as regulators of bone turnover and mediators of angiogenesis.

Interleukin-18 in multiple myeloma patients: serum levels in relation to response to treatment and survival.

Interleukin-18 (IL-18) plays a role in the host's response to tumours and angiogenesis. We determined serum levels of IL-18, vascular endothelial growth factor (VEGF), angiogenin (ANG), tumor necrosis factor (TNF-alpha) and CRP in 65 newly diagnosed myeloma patients. IL-18, VEGF, angiogenin, TNF-alpha and CRP were significantly higher at stage III in comparison to stages II and I. These cytokines (measured in 27 patients) significantly decreased after treatment. In survival analysis, higher levels of IL-18 were associated with a poorer prognosis. We conclude that increased serum IL-18 in myeloma patients correlates with advanced disease, increased levels of angiogenic cytokines and worse survival.

The clinical and prognostic significance of erythrocyte sedimentation rate (ESR), serum interleukin-6 (IL-6) and acute phase protein levels in multiple myeloma.

Interleukin-6 (IL-6) and acute phase proteins are commonly increased in patients with multiple myeloma. Several of these acute phase proteins are believed to predict prognosis and influence survival. We measured interleukin-6 (IL-6), C-reactive protein (CRP), alpha-1-antitrypsin (a1AT), acid alpha-1-glycoprotein (a1AG), haptoglobin (HAP), transferrin (TRF), hemoglobin (Hb), beta-2-microglobulin (beta2M) and erythrocyte sedimentation rate (ESR) in 42 newly diagnosed multiple myeloma patients and 25 normal controls. At the time of blood collection, nine patients were at stage I of disease, 14 at stage II, and 19 at stage III according to the Durie and Salmon myeloma staging system. Mean +/- SD values of IL-6, CRP, a1AT, a1AG, HAP, beta2M, and ESR were significantly higher and Hb significantly lower than those found in the controls. Univariate analysis, using the log-rank test, showed that among the acute phase proteins, serum CRP (P < 0.002), a1AT (P < 0.008) and ESR (P < 0.008) were significantly correlated with survival. However, when a multivariate Cox proportional hazard model was performed, ESR, CRP, a1AT, a1AG and beta2M were identified as independent prognostic factors, while the others were not. We conclude that ESR, a simple and easily performed marker, was found to be an independent prognostic factor for survival in patients with multiple myeloma.