Plasma YKL-40 and total and disease-specific mortality in the general population.

BACKGROUND: Increased plasma YKL-40 is associated with short-term survival in patients with cardiovascular disease and cancer. We tested the hypothesis that increased plasma YKL-40 is associated with total and disease-specific mortality in the general population. METHODS: We measured plasma YKL-40 in 8899 study participants, aged 20-95 years, in the Copenhagen City Heart Study from the Danish general population who were followed for 16 years: 3059 died, 2158 had ischemic cardiovascular disease, 2271 had cancer, and 2820 had other diseases associated with increased YKL-40. Hazard ratios for early death and absolute 10-year mortality rates were calculated according to plasma YKL-40 percentile groupings computed within sex and age decade: 0%-33%, 34%-66%, 67%-90%, 91%-95%, and 96%-100%. RESULTS: Median survival age decreased from 83 years for participants with plasma YKL-40 in category 0%-33% to 69 years in category 96%-100% (trend, P < 0.0001). Risk of early death was increased (multifactorially adjusted hazard ratios) by 10% for YKL-40 category 34%-66%, by 30% for 67%-90%, by 70% for 91%-95%, and by 90% for 96%-100% vs YKL-40 category 0%-33% (trend, P < 0.0001). Corresponding increases in participants with ischemic cardiovascular disease were 10%, 20%, 80%, and 60% (P < 0.0001); in those with cancer were 10%, 20%, 50%, and 70% (P < 0.0001); and in those with other diseases were 10%, 20%, 40%, and 60% (P < 0.0001). Highest absolute 10-year mortality rates were 78% and 90% in women and men, respectively, who were >70 years old, smoked, and were in YKL-40 category 96%-100%. CONCLUSIONS: Increased plasma YKL-40 is associated with risk of early death from cardiovascular disease, cancer, and other diseases in the general population.

Report of the European Myeloma Network on multiparametric flow cytometry in multiple myeloma and related disorders.

The European Myeloma Network (EMN) organized two flow cytometry workshops. The first aimed to identify specific indications for flow cytometry in patients with monoclonal gammopathies, and consensus technical approaches through a questionnaire-based review of current practice in participating laboratories. The second aimed to resolve outstanding technical issues and develop a consensus approach to analysis of plasma cells. The primary clinical applications identified were: differential diagnosis of neoplastic plasma cell disorders from reactive plasmacytosis; identifying risk of progression in patients with MGUS and detecting minimal residual disease. A range of technical recommendations were identified, including: 1) CD38, CD138 and CD45 should all be included in at least one tube for plasma cell identification and enumeration. The primary gate should be based on CD38 vs. CD138 expression; 2) after treatment, clonality assessment is only likely to be informative when combined with immunophenotype to detect abnormal cells. Flow cytometry is suitable for demonstrating a stringent complete remission; 3) for detection of abnormal plasma cells, a minimal panel should include CD19 and CD56. A preferred panel would also include CD20, CD117, CD28 and CD27; 4) discrepancies between the percentage of plasma cells detected by flow cytometry and morphology are primarily related to sample quality and it is, therefore, important to determine that marrow elements are present in follow-up samples, particularly normal plasma cells in MRD negative cases.

High serum YKL-40 concentration is associated with severe bone disease in newly diagnosed multiple myeloma patients.

OBJECTIVES: In multiple myeloma (MM) YKL-40 is present in the bone marrow microenvironment and is suggested to play a role in remodelling of the extracellular matrix. Here, the association between serum YKL-40 and severity of bone disease in MM is investigated. METHODS: Serum YKL-40 was measured in 34 MM patients at diagnosis. Bone disease was assessed by radiography and biochemical markers of bone metabolism. Patients were treated with conventional chemotherapy and followed for up to 30 months. RESULTS: Patients with a serum YKL-40 elevated above the age specific reference range (56%) had a higher total X-ray score (P = 0.003) and higher levels of the markers of bone resorption serum C-terminal telopeptide of collagen type I (P = 0.003), urine pyridinoline (P = 0.04) and urine deoxypyridinoline (P = 0.002), while the levels of urine N-terminal telopeptide of collagen type I (NTX-1) and the markers of bone formation equalled those seen in patients with a normal serum YKL-40. Serum YKL-40 level (beta = 7.6; P = 0.002) and urine NTX-1 (log(2)) (beta = 3.5; P = 0.006) were independent predictors of total X-ray score at diagnosis. Patients with elevated serum YKL-40 at diagnosis had shorter time to first osteolytic event compared to patients with normal serum YKL-40 (12 months vs. not reached; Log rank test: P = 0.03). CONCLUSIONS: Newly diagnosed MM patients with elevated serum concentrations of YKL-40 have more severe bone destruction including increased bone resorptive activity and shorter time to progression of bone disease. At this point, a potential role for YKL-40 in myeloma-related bone disease must be considered.

High serum concentration of YKL-40 is associated with short survival in patients with acute myeloid leukemia.

PURPOSE: YKL-40 is secreted by cancer cells, macrophages, and neutrophils. It may be a growth or differentiation factor, play a role in angiogenesis, or protect against apoptosis. High serum YKL-40 is associated with poor prognosis in solid carcinomas. The aim was to examine serum YKL-40 in patients with acute myeloid leukemia (AML). EXPERIMENTAL DESIGN: YKL-40 was measured by ELISA in serum from 77 patients recently diagnosed with AML before and during the first month of chemotherapy. RESULTS: Forty (52%) of the AML patients had elevated serum YKL-40 (compared with age-matched healthy subjects) and their survival was shorter than in patients with normal serum YKL-40 (median, 128 days; interquartile range, 18-629 days versus 386 days; interquartile range, 180-901; P=0.018 Mann-Whitney test). Univariate analysis of serum YKL-40 (logarithmically transformed and treated as a continuous covariate) showed significant association with survival within the first month after start of chemotherapy [hazard ratio (HR), 1.7; 95% confidence interval (CI), 1.2-2.4; P=0.002], first 12 months (HR, 1.6; 95% CI, 1.2-2.0; P=0.0002), and overall survival (HR, 1.3; 95% CI, 1.1-1.6; P=0.003). Multivariate Cox analysis showed that serum YKL-40 was an independent prognostic variable for survival (first month: HR, 1.7; P=0.011; 12 months: HR, 1.6; P=0.0002; overall survival: HR, 1.4; P=0.002). High serum YKL-40 at start of chemotherapy was a risk factor for pneumonia within the first month, and serum YKL-40 increased (P=0.002) at time of pneumonia and was unchanged in patients without infections. CONCLUSIONS: Serum YKL-40 is a prognostic biomarker of survival in AML patients. Its role in AML and infections needs to be determined.

N-terminal pro-C-type natriuretic peptide in serum associated with bone destruction in patients with multiple myeloma.

AIM: To examine whether N-terminal proCNP concentrations in serum is associated with bone destruction in patients with multiple myeloma. MATERIALS & METHODS: N-terminal proCNP and biochemical bone markers were measured in 153 patients. Radiographic bone disease and skeletal-related events were evaluated at specific time-points. RESULTS: N-terminal proCNP concentrations increased with age. High N-terminal proCNP concentrations were associated with high-risk disease and renal impairment. Renal function explained 22% of the variation. N-terminal proCNP concentrations correlated with serum bone ALP and serum PINP, but lacked association with bone resorption markers, radiographic bone disease and skeletal-related events. CONCLUSION: Serum N-terminal proCNP are associated with bone formation activity in patients with multiple myeloma, but should be interpreted with caution in patients with renal impairment.

Serum YKL-40: a new independent prognostic marker for skeletal complications in patients with multiple myeloma.

In a time of increasing treatment options for multiple myeloma bone disease, risk factors predicting progression need to be elucidated. This study investigated the value of serum YKL-40, previously shown to be associated with radiographic progression of bone destruction, as a predictor for time to clinical progression, i.e. skeletal-related events (SREs), in 230 newly diagnosed patients with multiple myeloma receiving intravenous bisphosphonates. Serum concentrations of YKL-40 and biochemical bone markers (CTX-MMP, CTX-I, PINP) were measured at diagnosis. Patients were evaluated every third month for SRE and at 9 and 24 months for radiographic progression. Elevated serum YKL-40 was seen in 47% of patients and associated with high-risk disease (International Staging System stage III; p < 0.001), increased bone resorption (serum CTX/MMP; p < 0.001) and early radiographic progression at 9 months (p = 0.01). Serum YKL-40 together with serum CTX-MMP/PINP ratio and World Health Organization status were independent predictors of time to first SRE.

Multiparametric flow cytometry profiling of neoplastic plasma cells in multiple myeloma.

BACKGROUND AND AIM: The clinical impact of multiparametric flow cytometry (MFC) in multiple myeloma (MM) is still unclear and under evaluation. Further progress relies on multiparametric profiling of the neoplastic plasma cell (PC) compartment to provide an accurate image of the stage of differentiation. The primary aim of this study was to perform global analysis of CD expression on the PC compartment and subsequently to evaluate the prognostic impact. Secondary aims were to study the diagnostic and predictive impact. DESIGN AND METHODS: The design included a retrospective analysis of MFC data generated from diagnostic bone marrow (BM) samples of 109 Nordic patients included in clinical trials within NMSG. Whole marrow were analyzed by MFC for identification of end-stage CD45(-) /CD38(++) neoplastic PC and registered the relative numbers of events and mean fluorescence intensity (MFI) staining for CD19, CD20, CD27, CD28, CD38, CD44, CD45, CD56, and isotypes for cluster analysis. RESULTS: The median MFC-PC number was 15%, and the median light microscopy (LM)-PC number was 35%. However, the numbers were significant correlated and the prognostic value with an increased relative risk (95% CI) of 3.1 (1.7-5.5) and 2.9 (1.4-6.2), P < 0.0003 and P < 0.004 of MFC-PC and LM-PC counts, respectively. Unsupervised clustering based on global MFI assessment on PC revealed two clusters based on CD expression profiling. Cluster I with high intensity for CD56, CD38, CD45, right-angle light-scatter signal (SSC), forward-angle light-scatter signal (FSC), and low for CD28, CD19, and a Cluster II, with low intensity of CD56, CD38, CD45, SSC, FSC, and high for CD28, CD19 with a median survival of 39 months and 19 months, respectively (P = 0.02). CONCLUSIONS: The MFC analysis of MM BM samples produces diagnostic, prognostic, and predictive information useful in clinical practice, which will be prospectively validated within the European Myeloma Network (EMN). © 2010 International Clinical Cytometry Society.

Elevated plasma YKL-40 predicts increased risk of gastrointestinal cancer and decreased survival after any cancer diagnosis in the general population.

PURPOSE: Elevated plasma YKL-40 is a biomarker of poor prognosis in cancer patients. We tested the hypotheses that elevated plasma YKL-40 predicts risk of cancer as well as survival after a cancer diagnosis in the general population. PATIENTS AND METHODS: A prospective cohort study of 8,899 subjects (20 to 95 years) from the Danish general population, the Copenhagen City Heart Study, observed for 11 years for cancer incidence and 14 years for death: 1,432 participants had a first incident cancer, 968 of these died. Hazard ratios (HRs) for cancer events and death after events according to plasma YKL-40 in sex and 10 years age percentile categories: 0% to 33%, 34% to 66%, 67% to 90%, 91% to 95%, and 96% to 100%. RESULTS: The cumulative incidence of gastrointestinal cancer increased with increasing YKL-40 (trend P < .0001). Multifactorially adjusted HRs for gastrointestinal cancer were 1.0 (95% CI, 0.7 to 1.5) for YKL-40 in category 34% to 66%, 1.5 for 67% to 90% (95% CI, 1.0 to 2.3), 2.4 for 91% to 95%, (95% CI, 1.3 to 4.6), and 3.4 for 96% to 100% (95% CI, 1.9 to 6.1) versus YKL-40 category 0% to 33% (P < .0001). Participants with any cancer event and YKL-40 category 91% to 100% had a median survival time after the diagnosis of 1 year versus 4 years in participants with YKL-40 category 0% to 33% (P < .0001). Corresponding values for gastrointestinal cancer were 6 months versus 1 year (P = .007). Multifactorially adjusted HRs for early death were 1.8 (95% CI, 1.3 to 2.5; P < .0001) after any cancer and 2.4 (95% CI, 1.3 to 4.3; P = .005) after gastrointestinal cancer in participants with YKL-40 category 91% to 100% versus 0% to 33%. CONCLUSION: In the general population, elevated plasma YKL-40 predicts increased risk of gastrointestinal cancer and decreased survival after any cancer diagnosis.

Serum YKL-40 concentrations in newly diagnosed multiple myeloma patients and YKL-40 expression in malignant plasma cells.

OBJECTIVES: A potential role in cancer biology is suggested for YKL-40 (CHI3L1, HC gp-39). The purpose of this study was to evaluate the clinical value of serum YKL-40 (sYKL-40) in multiple myeloma (MM) and to examine YKL-40 expression in malignant plasma cells (MM PCs). METHODS: sYKL-40 was measured by enzyme-linked immunosorbent assay (ELISA) in 82 patients with newly diagnosed MM. YKL-40 expression in immunophenotypically defined plasma cells was investigated by double-labelled immunohistochemistry in 21 MM patients and by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in cDNA archives generated by global RT-PCR in seven controls, 14 patients with monoclonal gammopathy of undetermined significance (MGUS), 45 MM patients, nine patients with extramedullary myeloma (exMM), and seven human myeloma cell lines (HMCLs). RESULTS: sYKL-40 was elevated above a constructed reference range for healthy controls in 29% of the patients investigated. Patients with elevated sYKL-40 had reduced overall survival and event-free survival when compared to patients with normal sYKL-40, but sYKL-40 level was defeated by beta(2)-microglobulin in the multivariate analyses. Intramedullary MM PCs lacked significant expression of YKL-40, but high levels of YKL-40 expression were seen in extramedullary MM PCs from one exMM patient and in six HMCLs. Further investigations of other bone marrow (BM) cells showed YKL-40 expression in megakaryocytes, neutrophils and adherent cells from long-term BM cultures. CONCLUSIONS: In newly diagnosed MM-patients, a sYKL-40 elevated above the reference range predicts a poor clinical outcome, and YKL-40 is expressed by other BM cells than MM PCs. At this point, routine measurements of sYKL-40 are not warranted, but YKL-40 should be considered as a potential player in the pathophysiology of MM.