Cell-Free DNA Fragmentomes in the Diagnostic Evaluation of Patients With Symptoms Suggestive of Lung Cancer

BACKGROUND

The diagnostic workup of individuals suspected of having lung cancer can be complex and protracted because conventional symptoms of lung cancer have low specificity and sensitivity.

RESEARCH QUESTION

Among individuals with symptoms of lung cancer, can a blood-based approach to analyze cell-free DNA (cfDNA) fragmentation (the DNA evaluation of fragments for early interception [DELFI] score) enhance evaluation for the possible presence of lung cancer?

STUDY DESIGN AND METHODS

Adults were referred to Bispebjerg Hospital (Copenhagen, Denmark) for diagnostic evaluation of initial imaging anomalies and symptoms consistent with lung cancer. Numbers and types of symptoms were extracted from medical records. cfDNA from plasma samples obtained at the prediagnostic visit was isolated, sequenced, and analyzed for genome-wide cfDNA fragmentation patterns. The relationships among clinical presentation, cancer status, and DELFI score were examined.

RESULTS

A total of 296 individuals were analyzed. Median DELFI scores were higher for those with lung cancer (n = 98) than those without cancer (n = 198; 0.94 vs 0.19; P < .001). In a multivariate model adjusted for age, smoking history, and presenting symptoms, the addition of the DELFI score improved the prediction of lung cancer for those who demonstrated symptoms (area under the receiver operating characteristic curve, 0.74-0.94).

INTERPRETATION

The DELFI score distinguishes individuals with lung cancer from those without cancer better than suspicious symptoms do. These results represent proof-of-concept support that fragmentation-based biomarker approaches may facilitate diagnostic resolution for patients with concerning symptoms of lung cancer.

Protein-altering germline mutations implicate novel genes related to lung cancer development

Few germline mutations are known to affect lung cancer risk. We performed analyses of rare variants from 39,146 individuals of European ancestry and investigated gene expression levels in 7,773 samples. We find a large-effect association with an ATM L2307F (rs56009889) mutation in adenocarcinoma for discovery (adjusted Odds Ratio = 8.82, P = 1.18 × 10-15) and replication (adjusted OR = 2.93, P = 2.22 × 10-3) that is more pronounced in females (adjusted OR = 6.81 and 3.19 and for discovery and replication). We observe an excess loss of heterozygosity in lung tumors among ATM L2307F allele carriers. L2307F is more frequent (4%) among Ashkenazi Jewish populations. We also observe an association in discovery (adjusted OR = 2.61, P = 7.98 × 10-22) and replication datasets (adjusted OR = 1.55, P = 0.06) with a loss-of-function mutation, Q4X (rs150665432) of an uncharacterized gene, KIAA0930. Our findings implicate germline genetic variants in ATM with lung cancer susceptibility and suggest KIAA0930 as a novel candidate gene for lung cancer risk.

Elevated plasma YKL-40 and risk of infectious disease: a prospective study of 94665 individuals from the general population

OBJECTIVES

YKL-40 is an acute phase protein elevated in patients with infectious and inflammatory diseases. We tested the hypothesis that baseline elevated YKL-40 is associated with increased risk of future infectious disease in healthy individuals in the general population.

METHODS

We prospectively followed 94 665 individuals from the Danish general population for up to 23 years and analysed for plasma YKL-40 levels (n = 21 584) and CHI3L1 rs4950928 genotype (n = 94 184). Endpoints were any infection, bacterial pneumonia, urinary tract infection, skin infection, sepsis, diarrhoeal disease, and other infections.

RESULTS

For YKL-40 percentile category 91-100% versus 0-33%, the multifactorially and C-reactive protein (CRP) adjusted hazard ratios were 1.71 (95% confidence interval 1.50-1.96; p 4 × 10^-14) for any infection, 1.97 (1.64-2.37; p 4 × 10^-13) for bacterial pneumonia, 1.62 (1.24-2.11; p 0.002) for urinary tract infection, 1.74 (1.31-2.32; p 2 × 10^-4) for skin infection, 1.76 (1.25-2.46; p 0.004) for sepsis, 1.90 (1.29-2.78; p 0.002) for diarrhoeal disease and 2.71 (1.38-5.35; p 0.01) for other infections. In multifactorially and CRP-adjusted models, a twofold increase in YKL-40 was associated with increased risk of all infectious disease endpoints. Mendelian randomization did not support causality, as CHI3L1 rs4950928 was associated with 94% and 190% higher YKL-40 levels (for CG and CC versus GG genotype), but not with increased risk of any infectious disease endpoint.

DISCUSSION

Baseline elevated plasma YKL-40 was not a cause but a strong marker of increased risk of future infectious diseases in individuals in the general population.

Antitumour immunity invoked by hepatic arterial infusion of first-line oxaliplatin predicts durable colorectal cancer control after liver metastasis ablation: 8-12 years of follow-up

In colorectal cancer (CRC), hepatic arterial infusion (HAI) chemotherapy may convert primarily unresectable CRC liver metastases (CLM) into resectability, although the risk of metastatic recurrence remains high after CLM ablation. We investigated the role of antitumour immunity invoked by first-line oxaliplatin-HAI for long-term CLM outcome. In a prospective study cohort of primarily unresectable CLM, we assessed patients' fms-related tyrosine kinase 3 ligand (FLT3LG) in serum, reflecting opportune intratumoural immune activity, at baseline and following 1-3 sequences of oxaliplatin-HAI. The end points were CLM resectability and overall survival. Patients who presented an immediate twofold increment of circulating FLT3LG during the treatment and at its completion were scored as CLM resectable (16.4% with both features), were alive at final follow-up 8-12 years later. All patients experienced FLT3LG increase during the treatment course, but those who remained unresectable or had the disease converted but presented a slow and gradual FLT3LG accretion, later died of the metastatic disease. These data provide further support to our previous findings that tumour-directed immunity invoked by oxaliplatin-containing therapy predicts excellent outcome of early advanced CRC if macroscopic tumour ablation is rendered possible by the 'classic' tumour response to the cytotoxic treatment.

Total circulating cell-free DNA as a prognostic biomarker in metastatic colorectal cancer before first-line oxaliplatin-based chemotherapy

BACKGROUND

Metastatic colorectal cancer (mCRC) is a heterogeneous disease where prognosis is dependent both on tumor biology and host factors. Total circulating cell-free DNA (cfDNA) has shown to harbor prognostic information in mCRC, although less is known about the biological correlates of cfDNA levels in this patient group. The primary objective was to evaluate the prognostic value of pretreatment cfDNA in patients receiving the first-line oxaliplatin-based chemotherapy for mCRC, by using a predefined upper limit of normal (ULN) from a cohort of presumed healthy individuals. The secondary objective was to model cfDNA levels as a function of predefined tumor and host factors.

PATIENTS AND METHODS

This was a retrospective post hoc study based on a prospective multicenter phase III trial, the NORDIC-VII study. DNA was purified from 547 plasma samples and cfDNA quantified by a droplet digital PCR assay (B2M, PPIA) with controls for lymphocyte contamination. Main clinical end point was overall survival (OS).

RESULTS

cfDNA was quantified in 493 patients, 54 were excluded mainly due to lymphocyte contamination. Median cfDNA level was 7673 alleles/ml (1050-1 645 000) for B2M and 5959 alleles/ml (555-854 167) for PPIA. High cfDNA levels were associated with impaired outcome; median OS of 16.6 months for levels above ULN and 25.9 months for levels below ULN (hazard ratio = 1.83, 95% confidence interval 1.51-2.21, P < 0.001). The result was confirmed in multivariate OS analysis adjusting for established clinicopathological characteristics. A linear regression model predicted cfDNA levels from sum of longest tumor diameters by RECIST, the presence of liver metastases and systemic inflammatory response as measured by interleukin 6 (F(6, 357) = 62.7, P < 0.001).

CONCLUSION

cfDNA holds promise as a minimally invasive and clinically relevant prognostic biomarker in mCRC before initiating first-line oxaliplatin-based chemotherapy and may be a complex entity associated with tumor burden, liver metastases and systemic inflammatory response.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT00145314.

Circulating cell-free DNA as predictor of treatment failure after neoadjuvant chemo-radiotherapy before surgery in patients with locally advanced rectal cancer

Background

Treatment of patients with locally advanced rectal cancer (LARC) is based on a combination of chemo-radiotherapy (CRT) and surgery. The rate of distant recurrences remains over 25%. Circulating cell-free DNA (cfDNA) in plasma is a mixture of normal and cancer-specific DNA segments and is a promising biomarker in patients with colorectal cancer. The aim of our study was to investigate plasma cfDNA as a prognostic marker for outcome in patients with LARC treated with neoadjuvant CRT and surgery.

Patients and methods

In total, 123 patients with LARC were included in 2 biomarker studies. Patients were treated with neoadjuvant CRT before TME surgery. Fifty-two (42%) of the patients received induction chemotherapy with capecitabine + oxaliplatin. Total cfDNA was measured by direct fluorescent assay in EDTA plasma samples obtained at baseline, after induction chemotherapy, and after CRT. Serial samples 5 years after surgery were collected in 51 patients (41%).

Results

Median follow-up was 55 months. Distant or local recurrence was seen in 30.9% of the patients. Patients with baseline cfDNA levels above the 75th quartile had a higher risk of local or distant recurrence and shorter time to recurrence compared with patients with plasma cfDNA below the 75th percentile (HR = 2.48, 95% CI: 1.3-4.8, P = 0.007). The same applied to disease-free survival (DFS) (HR = 2.43, 95% CI: 1.27-4.7, P = 0.015). In multivariate analysis, a high cfDNA level was significantly associated with time to progression and DFS. During follow-up, the association remained significant regardless of time point for sample analysis.

Conclusion

We have demonstrated an association between a high baseline plasma level of cfDNA and increased risk of recurrence, shorter time to recurrence, and shorter DFS in patients with LARC. Consequently, cfDNA could potentially improve pre- and post-treatment risk assessment and facilitate individualized therapy for patients with LARC.

Genetic interaction analysis among oncogenesis-related genes revealed novel genes and networks in lung cancer development

The development of cancer is driven by the accumulation of many oncogenesis-related genetic alterations and tumorigenesis is triggered by complex networks of involved genes rather than independent actions. To explore the epistasis existing among oncogenesis-related genes in lung cancer development, we conducted pairwise genetic interaction analyses among 35,031 SNPs from 2027 oncogenesis-related genes. The genotypes from three independent genome-wide association studies including a total of 24,037 lung cancer patients and 20,401 healthy controls with Caucasian ancestry were analyzed in the study. Using a two-stage study design including discovery and replication studies, and stringent Bonferroni correction for multiple statistical analysis, we identified significant genetic interactions between SNPs in RGL1:RAD51B (OR=0.44, p value=3.27x10-11 in overall lung cancer and OR=0.41, p value=9.71x10-11 in non-small cell lung cancer), SYNE1:RNF43 (OR=0.73, p value=1.01x10-12 in adenocarcinoma) and FHIT:TSPAN8 (OR=1.82, p value=7.62x10-11 in squamous cell carcinoma) in our analysis. None of these genes have been identified from previous main effect association studies in lung cancer. Further eQTL gene expression analysis in lung tissues provided information supporting the functional role of the identified epistasis in lung tumorigenesis. Gene set enrichment analysis revealed potential pathways and gene networks underlying molecular mechanisms in overall lung cancer as well as histology subtypes development. Our results provide evidence that genetic interactions between oncogenesis-related genes play an important role in lung tumorigenesis and epistasis analysis, combined with functional annotation, provides a valuable tool for uncovering functional novel susceptibility genes that contribute to lung cancer development by interacting with other modifier genes.

Methodological development and biological observations of cell free DNA with a simple direct fluorescent assay in colorectal cancer

BACKGROUND

Cell free DNA (cfDNA) has shown promising utility as prognostic biomarker for patients with colorectal cancer (CRC), with an ongoing need to optimize and validate the laboratory methodology. Here, we report our optimization and validation of a direct fluorescent assay and display the potential utility in patients with colorectal cancer.

METHODS

Plasma cfDNA was analyzed by a direct fluorescent assay (DFA) and compared to quantification by droplet digital PCR (ddPCR). For clinical validation, baseline blood samples were available for a total of 273 patients from six different Nordic trials, covering patients with locally advanced rectal cancer (n = 176, cohorts A + B), liver limited metastatic CRC (n = 75C + D) and wide spread metastatic CRC (n = 22 E + F).

RESULTS

Validating the DFA analysis with ddPCR revealed a strong correlation with an R2 of 0.81. For the clinical cohorts, the levels of cfDNA were: 0.8 ng/uL (95%CI 0.75-0.83) (A + B), 0.93 ng/uL (95%CI 0.86-1.02) (C + D) and 1.2 ng/uL (95%CI 0.85-1.47) (E + F), respectively (p < 0.01). All cohorts of colorectal cancer had higher levels of cell free DNA than healthy individuals (n = 94) (p < 0.01).

CONCLUSION

Analysis of cell free DNA by a direct fluorescent assay could be an attractive laboratory option for a rapid inexpensive quantification of cell free DNA.

Identification of susceptibility pathways for the role of chromosome 15q25.1 in modifying lung cancer risk

Genome-wide association studies (GWAS) identified the chromosome 15q25.1 locus as a leading susceptibility region for lung cancer. However, the pathogenic pathways, through which susceptibility SNPs within chromosome 15q25.1 affects lung cancer risk, have not been explored. We analyzed three cohorts with GWAS data consisting 42,901 individuals and lung expression quantitative trait loci (eQTL) data on 409 individuals to identify and validate the underlying pathways and to investigate the combined effect of genes from the identified susceptibility pathways. The KEGG neuroactive ligand receptor interaction pathway, two Reactome pathways, and 22 Gene Ontology terms were identified and replicated to be significantly associated with lung cancer risk, with P values less than 0.05 and FDR less than 0.1. Functional annotation of eQTL analysis results showed that the neuroactive ligand receptor interaction pathway and gated channel activity were involved in lung cancer risk. These pathways provide important insights for the etiology of lung cancer.

Predictive value of a multi-biomarker disease activity score for clinical remission and radiographic progression in patients with early rheumatoid arthritis: a post-hoc study of the OPERA trial

OBJECTIVES

Measurement of serum biomarkers at disease onset may improve prediction of disease course in patients with early rheumatoid arthritis (RA). We evaluated the multi-biomarker disease activity (MBDA) score and early changes in MBDA score for prediction of 28-joint Disease Activity Score based on C-reactive protein (DAS28-CRP) remission and radiographic progression in the double-blinded OPERA trial.

METHOD

Treatment-naïve RA patients (N = 180) with moderate or high DAS28 were randomized to methotrexate (MTX) + adalimumab (n = 89) or MTX + placebo (n = 91) in combination with glucocorticoid injection into swollen joints. X-rays of hands and feet were evaluated at months 0 and 12 (n = 164) by the total Sharp van der Heijde score (TSS). The smallest detectable change (1.8 TSS units) defined radiographic progression (∆TSS ≥ 2). Clinical remission (DAS28-CRP < 2.6) was assessed at baseline and 6 months. MBDA score was determined at 0 and 3 months and tested in a multivariable logistic regression model for predicting DAS28 remission at 6 months and radiographic progression at 1 year.

RESULTS

Baseline MBDA score was independently associated with radiographic progression at 1 year [odds ratio (OR) = 1.03/unit, 95% confidence interval (CI) = 1.01-1.06], and changes in MBDA score from baseline to 3 months with clinical remission at 6 months [OR = 0.98/unit, 95% CI 0.96-1.00). In anti-cyclic citrullinated peptide antibody (anti-CCP)-positive patients, 35 of 89 with high MBDA score (> 44) showed radiographic progression (PPV = 39%), compared with 0 of 15 patients (NPV = 100%) with low/moderate MBDA score (≤ 44) (p = 0.003).

CONCLUSION

Early changes in MBDA score were associated with clinical remission based on DAS28-CRP at 6 months. In anti-CCP-positive patients, a non-high baseline MBDA score (≤ 44) had a clinical value by predicting very low risk of radiographic progression at 12 months.

Genome-wide interaction study of smoking behavior and non-small cell lung cancer risk in Caucasian population

Non-small cell lung cancer is the most common type of lung cancer. Both environmental and genetic risk factors contribute to lung carcinogenesis. We conducted a genome-wide interaction analysis between single nucleotide polymorphisms (SNPs) and smoking status (never- versus ever-smokers) in a European-descent population. We adopted a two-step analysis strategy in the discovery stage: we first conducted a case-only interaction analysis to assess the relationship between SNPs and smoking behavior using 13336 non-small cell lung cancer cases. Candidate SNPs with P-value <0.001 were further analyzed using a standard case-control interaction analysis including 13970 controls. The significant SNPs with P-value <3.5 × 10-5 (correcting for multiple tests) from the case-control analysis in the discovery stage were further validated using an independent replication dataset comprising 5377 controls and 3054 non-small cell lung cancer cases. We further stratified the analysis by histological subtypes. Two novel SNPs, rs6441286 and rs17723637, were identified for overall lung cancer risk. The interaction odds ratio and meta-analysis P-value for these two SNPs were 1.24 with 6.96 × 10-7 and 1.37 with 3.49 × 10-7, respectively. In addition, interaction of smoking with rs4751674 was identified in squamous cell lung carcinoma with an odds ratio of 0.58 and P-value of 8.12 × 10-7. This study is by far the largest genome-wide SNP-smoking interaction analysis reported for lung cancer. The three identified novel SNPs provide potential candidate biomarkers for lung cancer risk screening and intervention. The results from our study reinforce that gene-smoking interactions play important roles in the etiology of lung cancer and account for part of the missing heritability of this disease.

Pre-Treatment Prediction of Chemoresistance in Second-Line Chemotherapy of Ovarian Carcinoma: Value of Serological Tumor Marker Determination (Tetranectin, YKL-40, CASA, CA 125)

Objective

To examine if the determination of the levels of serological tumor markers at time of relapse had any predictive value for chemoresistance in the second-line treatment of ovarian cancer patients.

Methods

From a registry of consecutive single-institution patients with epithelial ovarian carcinoma pretreated with paclitaxel plus platinum, we selected 82 patients with (a) solid tumor recurrence, and (b) second-line chemotherapy consisting of topotecan (platinum-resistant disease) or paclitaxel plus carboplatin (platinum-sensitive disease). Stored serum samples were analyzed for the biochemical tumor markers tetranectin, YKL-40, CASA (cancer-associated serum antigen), and CA 125. The serum tumor marker levels at time of relapse were correlated with response status at landmark time after 4 cycles of second-line chemotherapy. Univariate and multivariate logistic regression analyses (chemoresistant vs non-chemoresistant disease) were performed.

Results

At landmark time, 26% of patients had progression according to the GCIG (Gynecologic Cancer Intergroup) progression criteria. In univariate logistic regression analysis, the tumor markers tetranectin (OR 0.4; 95% CI: 0.2–0.8; p=0.008), YKL-40 (OR 1.8; 95% CI: 1.0–3.3; p=0.045), and CASA (OR 1.8; 95% CI: 1.2–2.7; p=0.007) had predictive value for second-line chemoresistance, whereas serum CA 125 had no predictive value. In a multivariate logistic regression analysis, serum tetranectin and CASA both had independent predictive value for chemoresistance. The combined determination of tetranectin and CASA had a specificity of 90% with 33% sensitivity for the prediction of chemoresistance (area under the receiver operating characteristic curve = 0.78; 95% CI: 0.66–0.91; p=0.001).

Conclusion

Low serum levels of tetranectin, or high serum levels of CASA or YKL-40, are associated with increased risk of second-line chemoresistance in patients with ovarian cancer.

Circulating serum interleukin-6, serum chitinase-3-like protein-1, and plasma vascular endothelial growth factor are not predictive for remission and radiographic progression in patients with early rheumatoid arthritis: post-hoc explorative and validation studies based on the CIMESTRA and OPERA trials

OBJECTIVE

To investigate serum interleukin-6 (IL-6), serum chitinase-3-like protein-1 (YKL-40), and plasma vascular endothelial growth factor (VEGF) as measures of disease activity and predictors of clinical remission and radiographic progression in two early rheumatoid arthritis (RA) randomized controlled trials (RCTs).

METHOD

Treatment-naïve patients with early RA (< 6 months' duration) and active disease, participating in two investigator-initiated RCTs, were treated according to a predefined treat-to-target algorithm aiming at inflammatory control, using methotrexate (MTX) + cyclosporine versus MTX + placebo (CIMESTRA study, n = 150, 5 year follow-up) or MTX + adalimumab versus MTX + placebo (OPERA study, n = 180, 2 year follow-up). The 28-joint Disease Activity Score (DAS28) and conventional radiography [bilateral hands and feet at baseline, 2 years and 5 years (only CIMESTRA)] were obtained at baseline and during follow-up. Serum IL-6, serum YKL-40, and plasma VEGF were measured in baseline blood samples and during follow-up. Hypotheses regarding the biomarkers' relation with DAS28 and ability to predict clinical remission (DAS28 < 2.6) and radiographic progression (change in total Sharp van der Heijde score ≥ 2) were generated in CIMESTRA and validated in OPERA, by Spearman's correlation and logistic regression analyses.

RESULTS

Baseline IL-6, YKL-40, and VEGF correlated significantly with DAS28 in CIMESTRA (r = 0.50, r = 0.36, r = 0.36, respectively, all p < 0.01) and these results were confirmed in OPERA patients (r = 0.52, p < 0.01; r = 0.18, p = 0.01; r = 0.23, p = 0.002, respectively). None of the biomarkers (absolute values or change) was predictive of clinical remission or radiographic progression at 2 or 5 years in either study.

CONCLUSION

Serum IL-6, serum YKL-40, and plasma VEGF were significantly correlated with DAS28 at baseline, but did not have consistent predictive value for clinical remission or radiographic progression in two early RA RCTs.

Large-scale association analysis identifies new lung cancer susceptibility loci and heterogeneity in genetic susceptibility across histological subtypes

Although several lung cancer susceptibility loci have been identified, much of the heritability for lung cancer remains unexplained. Here 14,803 cases and 12,262 controls of European descent were genotyped on the OncoArray and combined with existing data for an aggregated genome-wide association study (GWAS) analysis of lung cancer in 29,266 cases and 56,450 controls. We identified 18 susceptibility loci achieving genome-wide significance, including 10 new loci. The new loci highlight the striking heterogeneity in genetic susceptibility across the histological subtypes of lung cancer, with four loci associated with lung cancer overall and six loci associated with lung adenocarcinoma. Gene expression quantitative trait locus (eQTL) analysis in 1,425 normal lung tissue samples highlights RNASET2, SECISBP2L and NRG1 as candidate genes. Other loci include genes such as a cholinergic nicotinic receptor, CHRNA2, and the telomere-related genes OFBC1 and RTEL1. Further exploration of the target genes will continue to provide new insights into the etiology of lung cancer.

The effect of geriatric intervention in frail elderly patients receiving chemotherapy for colorectal cancer: a randomized trial (GERICO)

Background

Better surgical techniques, chemotherapy and biological therapy have improved survival in patients with colorectal cancer (CRC), most markedly in younger patients. About half of patients over 70 years receive dose reductions or early treatment discontinuation of the planned adjuvant or first-line treatment due to side effects. The Comprehensive Geriatric Assessment (CGA) is a multidisciplinary evaluation of an elderly individual’s health status. This assessment in older patients with cancer can predict survival, chemotherapy toxicity and morbidity.

Methods

This randomized phase II trial (GERICO) is designed to investigate whether comprehensive geriatric assessment and intervention before and during treatment with chemotherapy in frail elderly patients with stages II–IV CRC will increase the number of patients completing chemotherapy. All patients ≥70 years in whom chemotherapy for CRC is planned to start at Herlev and Gentofte Hospital are screened for frailty using the G8 questionnaire at the first visit to the outpatient clinic. The G8 questionnaire is a multi-domain screening tool to identify frail or vulnerable patients at risk of increased toxicity and morbidity. Frail patients are offered inclusion and are then randomized to two groups (the intervention group and the control group). Patients in the intervention group receive a full geriatric assessment of comorbidity, medication, psycho-cognitive function, physical, functional and nutrition status, and interventions are undertaken on identified health issues. Simultaneously, they are treated for their cancer according to international guidelines. Patients in the control group receive the same chemotherapy regimens and standard of care. Primary outcome is number of patients completing scheduled chemotherapy at starting dose. Secondary outcomes are dose reductions, treatment delays, toxicity, time to recurrence, survival, cancer-related mortality and quality of life.

Discussion

This ongoing trial is one of the first to evaluate the effect of geriatric intervention in frail elderly patients with CRC. The trial will provide new and valuable knowledge about whether it is beneficial for the elderly patient undergoing chemotherapy to be treated simultaneously by a geriatrician.

Trial registration

ClinicalTrials.gov ID: NCT02748811. The trial was registered retrospectively; registration date 04/28/2016.

Efficacy and toxicity of adjuvant chemotherapy in elderly patients with colorectal cancer: the ACCORE study

Background

Elderly patients with primary colorectal cancer (CRC) are less frequently treated with adjuvant chemotherapy than younger patients due to concerns regarding toxicity and efficiency. We investigated how age, performance status (PS) and comorbidity influence treatment outcomes.

Patients and methods

A retrospective single-centre study of 529 patients with stages II–III CRC treated with adjuvant chemotherapy (5-fluorouracil/capecitabine+/÷oxaliplatin) from 2001 to 2011 at Herlev Hospital, Denmark. Baseline characteristics, chemotherapy and outcome were analysed with respect to age after adjusting for PS and comorbidity.

Results

Elderly patients (>70 years) had significantly more comorbidity (p<0.001) and poorer PS (p=0.001) than younger patients. Elderly were more frequently treated with single-agent therapy (p=0.001) and at lower initial dose (p<0.001). There was no age-dependent difference in 3-year disease-free survival (DFS; HR 1.09, 95% CI 0.80 to 1.47, p=0.59), in grade 3–5 toxicity (29% vs 28%, p=0.86) or in 10-year CRC mortality (28%, HR 1.07, p=0.71). In elderly patients, a reduction in chemotherapy dose intensity compared with full dose had no impact on DFS or CRC mortality. Elderly patients receiving <50% of planned cycles had shorter DFS (HR=1.78, p=0.020) and higher CRC mortality (HR=2.17, p=0.027) than elderly receiving all cycles. Poor PS in younger and elderly patients was related to shorter DFS (HR=1.95, p=0.002; HR=1.6, p=0.035, respectively) and overall survival (OS; HR=2.28, p<0.001; HR=2.03, p=0.002). Comorbidity in younger patients was significantly related to shorter DFS (HR 2.72, p<0.001), OS (HR 3.16, p<0.001) and higher CRC mortality (HR 2.70, p=0.001).

Conclusions

Choice of regimen, primary dose reduction and given dose intensity in patients treated with adjuvant chemotherapy for CRC were highly dependent on age. However, age had no impact on DFS and CRC mortality. Comorbidity in younger patients and PS in all patients were associated with shorter DFS and higher CRC mortality.

YKL-40 in allogeneic hematopoietic cell transplantation after AML and myelodysplastic syndrome

YKL-40, also called chitinase-3-like-1 protein, is an inflammatory biomarker that has been associated with disease severity in inflammatory and malignant diseases, including AML, multiple myeloma and lymphomas. The objective of the current study was to assess the prognostic value of pretransplant recipient and donor plasma YKL-40 concentrations in patients with AML (n=624) or myelodysplastic syndrome (n=157) treated with allogeneic hematopoietic cell transplantation (HCT). In recipients, the plasma YKL-40 concentrations were increased when the HCT-comorbidity index was ⩾5 (P=0.028). There were no significant associations between plasma YKL-40 concentrations in recipients and any outcome measures. In donors with YKL-40 plasma concentrations above the age-adjusted 95th percentile, a trend toward increased grade II-IV acute GvHD in recipients was observed (adjusted hazard ratio 1.39 (95% confidence interval 1.00-1.94), P=0.050), with no significant associations with overall survival, treatment-related mortality or relapse. In conclusion, our study shows that YKL-40 does not aid risk stratification of patients undergoing allogeneic HCT, but suggests that YKL-40 may aid donor selection when multiple, otherwise equal, donors are available.

Role of inflammatory marker YKL-40 in the diagnosis, prognosis and cause of cardiovascular and liver diseases

This review summarizes present evidence for the role of YKL-40 in the diagnosis, prognosis and cause of cardiovascular and alcoholic liver disease. The question of whether YKL-40 is merely a marker or a causal factor in the development of cardiovascular and liver disease is addressed, with emphasis on the Mendelian randomization design. The Mendelian randomization approach uses genetic variants associated with lifelong high plasma YKL-40 levels that are largely unconfounded and not prone to reverse causation. Thus, the approach mimics a controlled double-blind randomized trial, but it uses genetic variants rather than a drug and placebo, and like a blinded trial, it allows inference about causality. Moreover, the review also covers background on the molecular biology and functions of YKL-40, YKL-40 levels in healthy individuals and reference range, and the role of YKL-40 as a biomarker of cardiovascular and alcoholic liver disease. YKL-40 is a plasma protein named after its three N-terminal amino acids, Y (tyrosine), K (lysine) and L (leucine), and its molecular weight of 40 kDa. It is produced by local inflammatory cells in inflamed tissues, such as lipid-laden macrophages inside the vessel wall and perhaps also hepatic stellate cells. Observational studies show that plasma YKL-40 levels are elevated in patients with cardiovascular and liver disease and are associated with disease severity and prognosis. Furthermore, elevated plasma YKL-40 levels in apparently healthy individuals are associated with a 2-fold increased risk of future ischemic stroke and venous thromboembolism, but not with myocardial infarction, suggesting that YKL-40 could play a role in the formation of embolisms rather than atherosclerosis per se. Further, elevated YKL-40 levels combined with excessive alcohol consumption are associated with 10-years risk of alcoholic liver cirrhosis of up to 7%, suggesting that YKL-40 can be used as a strong noninvasive marker of predicting alcoholic liver cirrhosis. Importantly, in Mendelian randomization studies, genetically elevated plasma YKL-40 levels were not associated with risk of cardiovascular and alcoholic liver disease, thus suggesting that plasma YKL-40 does not play a causal role in the development of these diseases. Despite this, plasma YKL-40 levels may play a role in disease progression after diagnosis, and inhibition of YKL-40 activity might be a novel therapy in some cardiovascular and liver diseases.

Clinical and radiographic outcome of a treat-to-target strategy using methotrexate and intra-articular glucocorticoids with or without adalimumab induction: a 2-year investigator-initiated, double-blinded, randomised, controlled trial (OPERA)

OBJECTIVES

To study clinical and radiographic outcomes after withdrawing 1 year's adalimumab induction therapy for early rheumatoid arthritis (eRA) added to a methotrexate and intra-articular triamcinolone hexacetonide treat-to-target strategy (NCT00660647).

METHODS

Disease-modifying antirheumatic drug (DMARD)-naive patients with eRA started methotrexate (20 mg/week) and intra-articular triamcinolone (20 mg/ml) for 2 years. In addition, they were randomised to receive placebo adalimumab (DMARD group, n=91) or adalimumab (40 mg/every other week) (DMARD+adalimumab group, n=89) during the first year. Sulfasalazine and hydroxychloroquine were added if disease activity persisted after 3 months. During year 2, synthetic DMARDs continued. Adalimumab was (re)initiated if active disease reoccurred. Clinical response, remission, disability, quality of life and radiographic changes were assessed.

RESULTS

One year after adalimumab withdrawal, treatment profiles and clinical responses did not differ between groups. In the DMARD/DMARD+adalimumab groups, the median 2-year methotrexate dose was 20/20 mg/week (p=0.45), triple DMARD therapy had been initiated in 33/27 patients (p=0.49), adalimumab was (re)initiated in 12/12 patients and cumulative triamcinolone dose was 160/120 mg (p=0.15). The treatment target (disease activity score, 4 variables, C-reactive protein (DAS28CRP) ≤3.2 or DAS28>3.2 without swollen joints) was achieved at all visits in ≥85% of patients in year 2; remission rates were DAS28CRP<2.6:69%/66%; Clinical Disease Activity Index ≤2.8:55%/57%; Simplified Disease Activity Index <3.3:54%/49%; American College of Rheumatology/European League against Rheumatism (28 joints):44%/45% (p=0.66-1.00). Radiographic progression (Δtotal Sharp score/year) was similar 1.31/0.53 (p=0.12). Erosive progression (Δerosion score (ES)/year) was year 1:0.57/0.06 (p=0.02); year 2:0.38/0.05 (p=0.005). Proportion of patients without erosive progression (ΔES≤0) was year 1: 59%/76% (p=0.03); year 2:64%/79% (p=0.04).

CONCLUSIONS

An aggressive triamcinolone and synthetic DMARD treat-to-target strategy in eRA provided excellent 2-year clinical and radiographic disease control independent of adalimumab induction therapy. ES progression was slightly less during and following adalimumab induction therapy.

TRIAL REGISTRATION NUMBER

NCT00660647.

Primary tumor location and bevacizumab effectiveness in patients with metastatic colorectal cancer

BACKGROUND

There is an unmet need for predictive markers for the antiangiogenic agent bevacizumab in metastatic colorectal cancer (mCRC). We aimed to assess whether the location of the primary tumor is associated with bevacizumab effectiveness when combined with capecitabine and oxaliplatin (CAPEOX) in the first-line treatment of patients with mCRC.

PATIENTS AND METHODS

A cohort of 667 consecutive patients with mCRC from the general community treated from 2006 to 2011 with CAPEOX and bevacizumab as standard first-line therapy was compared with a cohort of 213 patients treated with CAPEOX from 2003 to 2006, before bevacizumab was approved. Main outcome measures were progression-free survival (PFS) and overall survival (OS). Differences in outcome were tested using Kaplan-Meier curves and log-rank tests, and multivariate analyses were carried out using Cox Proportional Hazards models.

RESULTS

Patients treated with CAPEOX and bevacizumab with primary tumors originating in the sigmoid colon and rectum had a significantly better outcome than patients with primary tumors originating from the cecum to the descending colon, both for PFS (median PFS 9.3 versus 7.2 months; hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.56-0.82) and for OS (median OS 23.5 versus 13.0 months; HR 0.47, 95% CI 0.38-0.57). This difference was confirmed in multivariate analyses after adjustment for other potentially prognostic factors. For patients treated with CAPEOX, there was no association between primary tumor location and outcome, neither in unadjusted nor adjusted analyses.

CONCLUSIONS

The addition of bevacizumab to CAPEOX in first-line treatment of patients with mCRC may primarily benefit patients with primary tumors originating in the rectum and sigmoid colon. This hypothesis needs to be validated in data from completed randomized trials.

CLINICALTRIALSGOV IDENTIFICATION NUMBER

NCT00212615.

The inflammatory biomarker YKL-40 at admission is a strong predictor of overall mortality

OBJECTIVES

YKL-40 is an inflammatory biomarker associated with disease activity and mortality in patients with diseases characterized by inflammation and tissue remodelling. The aim of this study was to describe the prognostic value of YKL-40 in an unselected patient population.

DESIGN

In consecutive patients admitted to hospital during a 1-year period, blood was collected and information regarding final diagnosis and mortality was collected. Median follow-up time was 11.5 years.

SETTING

District hospital, Copenhagen, Denmark.

PATIENTS

A total of 1407 patients >40 years of age were admitted acutely.

MAIN OUTCOME MEASURE

All-cause mortality.

RESULTS

Median YKL-40 was increased in patients (157 μg L(-1) , range 13-7704 μg L(-1) ) compared to healthy controls (40 μg L(-1) , range 29-58 μg L(-1) ; P < 0.001). Patients with YKL-40 in the highest quartile had a hazard ratio (HR) of 7.1 [95% confidence interval (CI) 4.2-12.0] for all-cause mortality in the first year and 3.4 (95% CI 2.8-4.2) in the total study period, compared to those in the lowest quartile (HR = 1). The HR for death for all patients with YKL-40 above the normal age-corrected 95th percentile was 2.1 (95% CI 1.6-2.7) after 1 year and 1.5 (95% CI 1.3-1.7) during the total study period, compared to patients with YKL-40 below the age-corrected 95th percentile. The results of multivariable analysis showed that YKL-40 was an independent biomarker of mortality; this was most significant in the first year. YKL-40 was a marker of prognosis in all disease categories. The HR for death was increased in patients with YKL-40 above the normal age-corrected 95th percentile in healthy subjects independent of type of disease (all P < 0.001).

CONCLUSION

The level of YKL-40 at admission is a strong predictor of overall mortality, independent of diagnosis and could be useful as a biomarker in the acute evaluation of all patients.

Bone metabolism and bone status in osteoporotic patients

We have studied bone turnover and bone status in 29 patients with hip fractures and compared them with normal subjects and patients with arthritis of the hip. Markers for bone formation, bone Gla protein, alkaline phosphatase and whole body retention of 99mTc-diphosphonate, and fasting urinary hydroxyproline, a marker for bone resorption, were all significantly higher in the hip fracture group than in the control group. The serum concentrations of 1,25-dihydroxyvitamin D were similar in the three groups, whereas the serum 25-hydroxyvitamin D concentration in the control group was higher than in the patient groups. The bone mineral content (BMC) measured in the distal forearm and the spine was lower than normal in the hip fracture group. We conclude that patients with hip fractures have an increased bone turnover with no signs of bimodality and low BMC values at all locations.

High serum YKL-40 level in a cohort of octogenarians is associated with increased risk of all-cause mortality

YKL-40 is secreted by macrophages, neutrophils, chondrocytes, endothelial-, vascular smooth muscle- and cancer cells. Interleukin (IL)-6 stimulates YKL-40 production in human in vivo studies. High serum YKL-40 is associated with poor prognosis in patients with inflammatory diseases and cancer. We studied whether serum YKL-40 was associated with systemic low-level inflammation, an immune risk phenotype, and mortality in relatively healthy 80-year old humans. Serum YKL-40, IL-6 and tumour necrosis factor (TNF)-alpha were measured by enzyme-linked immunosorbent assays (ELISAs) in octogenarians (n = 151) and serum YKL-40 in 18-30-year-olds (n = 89). Fifty-one of the octogenarians died during the 6-year follow-up. Serum YKL-40 in octogenarians was higher compared to the level in young people (median 116 versus 31 microg/l, P < 0.0005). Serum YKL-40 correlated with serum IL-6 in elderly women (Spearman's rho = 0.30, P = 0.009) and men (rho = 0.25, P = 0.003), but only with serum TNF-alpha (rho = 0.23, P = 0.05) and C-reactive protein (CRP) (rho = 0.57, P < 0.0005) among the elderly women. In addition, high serum level of YKL-40 was associated with a low CD4 : CD8 cell ratio. Univariate analysis of serum YKL-40 (logarithmically transformed and divided by tertiles) showed significant association with all-cause mortality [tertile 3: hazard ratio (HR) = 2.38, 95% confidence interval (CI): 1.19-4.78, P = 0.02]. The effect persisted after adjusting for potential confounders (sex, smoking, body mass index, chronic disease and anti-inflammatory medicine). These results suggest that serum YKL-40 is a prognostic and sensitive biomarker of all-cause mortality in octogenarians.

YKL-40, a biomarker of inflammation, is elevated in patients with type 2 diabetes and is related to insulin resistance

OBJECTIVE AND DESIGN

YKL-40 participates in inflammatory states and vascular processes, which implies that comparison can be made with other inflammatory markers associated with insulin resistance and type 2 diabetes (T2D). In the present study levels of plasma YKL-40 and serum hsCRP were evaluated in patients with T2D.

MATERIALS AND METHODS

Patients with T2D and age-matched healthy controls participated in the study. Insulin resistance was estimated using HOMA-IR model. Biochemical parameters were measured in venous blood after a 10 h fast.

RESULTS

Patients with T2D were insulin resistant (p<0.001) and had raised levels of plasma YKL-40 (p<0.001) and serum hsCRP (p<0.001). YKL-40 was correlated with HOMA-IR (r=0.23, p<0.01), NEFA (r=0.32, p<0.001) and triglycerides (r=0.24, p<0.05). YKL-40 and hsCRP were not correlated (r=0.17, p=NS). All participants with hsCRP<1 mg/l had higher insulin sensitivity (p<0.05 and p<0.01, respectively). HsCRP were predicted by HOMA-IR and BMI (r2=0.48, p<0.01). Plasma YKL-40 was predicted by HOMA-IR and triglycerides (r2=0.27, p<0.01).

CONCLUSIONS

YKL-40 and hsCRP are elevated in patients with T2D and are related to insulin resistance. No correlation was found between YKL-40 and hsCRP indicating that increased levels of YKL-40 occur independently from elevated plasma hsCRP.

High serum levels of YKL-40 in patients with systemic sclerosis are associated with pulmonary involvement

OBJECTIVES

YKL-40, a growth factor of connective tissue cells, is elevated in sera from patients with diseases characterized by inflammation, tissue remodelling, or fibrosis. The aim of the study was to determine serum YKL-40 levels in patients with systemic sclerosis (SSc) and to explore any possible clinical and prognostic associations.

METHODS

YKL-40 was measured in sera from 88 patients with SSc (26 with diffuse and 62 with limited skin involvement) and in sera from 88 matched healthy controls. Immunohistochemical staining for YKL-40 antigen was performed in a biopsy from a patient with pulmonary SSc.

RESULTS

Serum YKL-40 levels of the SSc patients were significantly higher than those of the controls (p<0.00001). Patients with pulmonary fibrosis by chest X-ray, obstructive ventilatory pattern, reduced diffusing capacity (DLco), and digital joint deformity due to skin retraction had significantly higher serum YKL-40 compared with patients without these findings. Patients with elevated serum YKL-40 had shorter survival times than patients with normal serum YKL-40 (p = 0.0005), although this was not independent of age and pulmonary function. YKL-40 protein expression was found in inflammatory cells in fibrosing pulmonary tissue from a patient with SSc.

CONCLUSIONS

Serum YKL-40 is elevated in patients with SSc with pulmonary involvement.

Circulating YKL-40 levels during human endotoxaemia

YKL-40 is secreted by macrophages and neutrophils and patients with bacterial infections have elevated circulating YKL-40. The aim was to evaluate changes in plasma YKL-40 (determined by enzyme-linked immunosorbent assay (ELISA) at 0, 2, 4, 8, 24 and 32 h) in eight healthy volunteers after injection with Esherichia coli endotoxin or saline. Plasma YKL-40 increased after endotoxin injection from 31 microg/l (range 19-39 microg/l) to a maximum of 159 microg/l (61-552 microg/l, P < 0.01) at 24 h. The finding that plasma YKL-40 increased after endotoxin injection compared with saline (P < 0.001) suggests that YKL-40 has a functional role in infections.

Magnetic resonance imaging for accelerated assessment of drug effect and prediction of subsequent radiographic progression in rheumatoid arthritis: a study of patients receiving combined anakinra and methotrexate treatment

OBJECTIVES

By MRI to assess the efficacy of addition of anakinra for controlling synovitis and stopping erosive progression in patients with clinically active RA despite receiving methotrexate, and to determine the predictive value of MRI for subsequent radiographic erosive progression.

METHODS

100 mg anakinra subcutaneously/day was added to the treatment of 17 patients with clinically active RA despite methotrexate. MRI of the non-dominant wrist and 2nd-5th MCP joints (OMERACT evaluation) was performed at weeks 0, 12, and 36, and radiography of both hands and wrists (modified Sharp evaluation) at weeks 0 and 36.

RESULTS

MRI synovitis scores were not significantly changed. Radiography of both hands and wrists after 36 weeks showed erosive progression in 11 patients, and MRI after 12 weeks in 10 patients. Nine of 10 patients with MRI progression at 12 weeks had radiographic progression at 36 weeks. Baseline MRI synovitis and erosion scores, but no clinical/biochemical parameters, correlated significantly with subsequent erosive progression.

CONCLUSION

Addition of anakinra did not significantly reduce MRI signs of synovitis, and most patients had progressive joint destruction. Baseline MRI findings predicted subsequent radiographic erosive progression. Unilateral wrist and MCP joint MRI after 12 weeks had a similar sensitivity for detection of erosive progression as bilateral hand and wrist radiography after 36 weeks.

Serum YKL-40, a potential new marker of disease activity in patients with inflammatory bowel disease

BACKGROUND

YKL-40 is secreted by macrophages and neutrophils and is a growth factor for vascular endothelial cells and fibroblasts. Elevated serum concentrations of YKL-40 are found in patients with diseases characterized by inflammation or ongoing fibrosis. The aim of this study was to seek association between serum YKL-40 in patients with ulcerative colitis (UC) and Crohn disease (CD) and clinical disease activity.

METHODS

One-hundred-and-sixty-four patients with UC and 173 patients with CD were studied. The Simple Clinical Colitis Activity Index (SCCAI) and the Harvey-Bradshaw (H-B) score were used to assess disease activity. Serum YKL-40 (determined by ELISA) was related to C-reactive protein (CRP) and disease activity.

RESULTS

In patients with UC, the median serum YKL-40 rose with increasing disease activity, and patients with severe active disease had higher serum YKL-40 (median 59 microg/L (95% CI: 26-258 microg/L), P < 0.001) than patients with inactive UC (33 microg/L (19-163)) and age-matched controls (43 microg/L (20-124)). Patients with severe active CD had higher serum YKL-40 (59 microg/L (21-654), P < 0.001) than age-matched controls, but not higher than inactive CD patients (43 microg/L (17-306)). Serum YKL-40 was elevated in 41% of the patients with severe UC, in 10% with inactive UC, in 46% with severe CD and in 30% with inactive CD. Serum YKL-40 correlated with SCCAI in UC patients but not with H-B score in CD patients. In both patient groups, low correlations were found between serum YKL-40 and CRP, albumin and leucocytes.

CONCLUSIONS

Serum YKL-40 is elevated in patients with active IBD and may be complementary to inflammatory markers and clinical characteristics in the assessment of disease activity.

Effect of antiviral therapy on markers of fibrogenesis in patients with chronic hepatitis C

BACKGROUND

The possible markers of liver fibrosis (plasma YKL-40, PIIINP, MMP-2 and TIMP-1) were measured at the start (t0) and end of treatment (t12) with alpha-interferon and ribavirin and repeated at 6-months follow-up (t18) in 51 patients with chronic hepatitis C.

METHODS

We evaluated 1) whether treatment response is reflected by a decrease in these markers during antiviral therapy; 2) whether these markers reflect the activity of the disease; and 3) whether these markers could be used as predictors of the treatment response.

RESULTS

Baseline plasma YKL-40, MMP-2, PIIINP and TIMP-1 were significantly increased in patients compared to normal controls. In responders (n = 30), plasma YKL-40 (P < 0.05), MMP-2 (P < 0.05) and TIMP-1 (P < 0.001) decreased significantly at t18, and no changes were observed at t12. Plasma PIIINP was unchanged in responders. In non-responders (n = 19), plasma MMP-2 (P < 0.01) and TIMP-1 (P < 0.01) decreased significantly at t18, whereas plasma YKL-40 and PIIINP were unchanged. The markers were significantly correlated at baseline (P < 0.001). Plasma PIIINP at baseline could predict treatment response (P = 0.01).

CONCLUSIONS

Response to antiviral treatment is associated with a decrease in the fibrogenetic markers, but the markers do not reflect the biochemical disease activity during treatment. Baseline plasma PIIINP was the only marker predicting treatment response.

Serum YKL-40 concentrations in patients with early rheumatoid arthritis: relation to joint destruction

OBJECTIVE

YKL-40 is a secretory glycoprotein of chondrocytes, synovial cells, macrophages, and neutrophils. The aims were to determine serum YKL-40 in patients with early rheumatoid arthritis (RA) and seek associations with early joint erosions.

METHODS

YKL-40 was measured by ELISA in serum samples collected every three month for 36 months from patients with early RA. The patients were treated with DMARDs and some were allocated to additional prednisolone.

RESULTS

Serum YKL-40 was higher in RA patients compared with controls (98 vs. 42 microg/l, p<0.001). The mean serum YKL-40 during the study correlated with the progression in Larsen score (Pearson's test: p=0.004). Patients with a persistently high serum YKL-40 had larger progression in Larsen score compared with patients with normal serum YKL-40 (median progression: 7 vs. 0, p=0.003).

CONCLUSION

These data suggest that elevated serum YKL-40 is related to progression in joint destruction in early RA patients.

Studies on YKL-40 in knee joints of patients with rheumatoid arthritis and osteoarthritis. Involvement of YKL-40 in the joint pathology

OBJECTIVE

The presence of YKL-40 (human cartilage glycoprotein 39) in synovium, cartilage and synovial fluid (SF) from knee joints of patients with rheumatoid arthritis and osteoarthritis (OA) were related to histopathological changes in synovium and cartilage and to serum YKL-40 and other biochemical markers.

METHODS

The localization of YKL-40 in synovium and cartilage was determined by immunohistochemistry. Synovial inflammation was estimated histologically and by magnetic resonance imaging (MRI). Biochemical markers of inflammation, neutrophil activation and cartilage metabolism were analysed. YKL-40 concentrations in serum and SF were determined by RIA and ELISA.

RESULTS

In the synovium YKL-40 positive cells were found in lining and stromal cells (macrophages) and the number of YKL-40 positive cells was related to the degree of synovitis. In arthritic cartilage, YKL-40 was located to chondrocytes. YKL-40 levels in SF were higher in RA patients with moderate/severe or none/slight synovitis of the knee joint compared to OA patients with moderate/severe or none/slight synovitis. SF YKL-40 correlated with the synovial membrane and the joint effusion volumes determined by magnetic resonance imaging (MRI) and with other biochemical markers of intercellular matrix metabolism. SF YKL-40 was higher than serum YKL-40, and a relationship existed between the YKL-40 levels in SF and serum. Intraarticular glucocorticoid injection was followed by clinical remission and a decrease in serum YKL-40, which increased again at clinical relapse.

CONCLUSIONS

YKL-40 in SF is derived from cells in the inflamed synovium, chondrocytes and SF neutrophils. Joint derived YKL-40 influences serum YKL-40. YKL-40 may be involved in the pathophysiology of the arthritic processes and reflect local disease activity.

Regulation of YKL-40 production by human articular chondrocytes

OBJECTIVE

YKL-40 (human cartilage glycoprotein 39) is one of the most abundant proteins secreted by cultured chondrocytes. The objectives of the present study were to identify regulators of YKL-40 production in cartilage and chondrocytes and to map the localization of YKL-40 in chondrocytes.

METHODS

Human articular chondrocytes and cartilage explants (obtained from subjects at autopsy, from a tissue bank, and from osteoarthritis [OA] patients undergoing total joint replacement surgery) were stimulated with cytokines, growth factors, and other agents. YKL-40 expression was analyzed by Northern blot and polymerase chain reaction. YKL-40 secretion into the media was determined by enzyme-linked immunosorbent assay.

RESULTS

YKL-40 production increased to very high levels during the early phase of chondrocyte monolayer culture and in normal cartilage explant cultures as a response to tissue injury. Spontaneous YKL-40 release was higher in OA than in normal cartilage explant cultures. In chondrocyte monolayer cultures, interleukin-1beta (IL-1beta) and transforming growth factor beta (TGFbeta) decreased the levels of secreted YKL-40, and this was associated with a reduction in YKL-40 messenger RNA levels. IL-1beta, but not TGFbeta, reduced YKL-40 production in cartilage explant cultures. Media from explants treated with cycloheximide had no detectable YKL-40, suggesting that the released protein was newly synthesized. Immunofluorescence microscopy showed YKL-40 staining in the Golgi system of the chondrocytes, but YKL-40 could not be detected in the extracellular matrix.

CONCLUSION

The spontaneous increase in the production of YKL-40 in the early phase of culture appears to represent a cellular response to changes in the extracellular matrix environment. This, coupled with the profound suppressive effects of IL-1beta and TGFbeta on YKL-40 production, identifies a novel regulatory pattern for this major chondrocyte-derived protein.

Accumulation of the neutrophil-derived protein YKL-40 during storage of various blood components

OBJECTIVE AND DESIGN

Post transfusion infectious complications associated with allogeneic blood components may depend on storage time and may be related to extracellular accumulation of bioactive substances during storage. YKL-40 is a glycoprotein located in the specific granules of the neutrophils. While exocytosed it may play a role in inflammation and remodelling of the extracellular matrix. We studied the potential accumulation of YKL-40 in blood components during storage.

METHODS

Using a RIA method extracellular accumulation of YKL-40 was determined in supernatants from whole blood, plasma-reduced whole blood, buffy-coat-depleted SAGM (saline-adenine-glucose-mannitol) blood, whole blood leukocyte depleted by prestorage filtration, and whole blood leukocyte depleted by bedside filtration. The blood was donated by volunteer, healthy blood donors, and stored under standard blood bank conditions for 35 days.

RESULTS

Extracellular accumulation of YKL-40 increased significantly in a time-dependent manner during storage for 35 days of non-filtered whole blood, plasma-reduced whole blood, and SAGM blood, respectively. Prestorage leukocyte depletion of whole blood prevented extracellular YKL-40 accumulation, while YKL-40 accumulation was not reduced by bedside leukocyte depletion.

CONCLUSION

YKL-40 appears to accumulate extracellularly in a time-dependent manner in standard erythrocyte components. Prestorage leukocyte depletion by filtration of whole blood may be an effective procedure to prevent extracellular YKL-40 accumulation during storage of erythrocyte components.

Stability of YKL-40 concentration in blood samples

The stability of YKL-40, a mammalian member of the family of 18 glycosylhydrolases, in blood samples handled under different temperatures and different time intervals before centrifugation was studied in paired serum and plasma samples from 25 healthy premenopausal Danish women. Significant elevations of YKL-40 were found in 8 paired serum samples left on the clot for more than 3 h at room temperature compared to paired serum samples left on the clot for 3 h or less. Significant elevations of YKL-40 were found in 8 paired plasma (EDTA) samples left on the blood cells for more than 8 h at room temperature compared to paired plasma (EDTA) samples left on the blood cells for 8 h or less. No elevations were found in YKL-40 levels in serum samples left on the clot at 4 degrees C for 24 h or in plasma (EDTA) samples left on the blood cells for 72 h before centrifugation. Significantly lower concentrations of YKL-40 were measured in plasma (EDTA) compared with paired serum samples with a serum/plasma ratio of 1.4 in samples left on the clot or on blood cells at 4 degrees C for up to 24 h. Repetitive freezing and thawing had no significant effect on the measured YKL-40 concentrations. In conclusion, we have shown that YKL-40 is very dependent on the handling procedures. All the blood samples must be processed into plasma (EDTA) within 8 h at room temperature or into serum in less than 3 h at room temperature. If this is not possible, the blood samples must be stored at 4 degrees C until processed.

Serum YKL-40 is increased in patients with hepatic fibrosis

BACKGROUND/AIMS

YKL-40, a mammalian member of the chitinase family, is a lectin that binds heparin and chitin. The function of YKL-40 is unknown, but it may function in tissue remodelling. The aims of this study were to assess the level of circulating YKL-40 in patients with various kinds and degree of chronic liver disease and its possible relation to liver fibrosis.

METHODS

Serum YKL-40 levels were determined by radioimmunoassay in 129 patients with suspected liver disease and related to histological findings and immunohistochemical staining of YKL-40 in a liver biopsy taken simultaneously with the blood sample.

RESULTS

The median serum YKL-40 was highest in patients with alcoholic cirrhosis (532 microg/l), in particular in patients with additional alcoholic hepatitis (740 microg/l). Patients with alcoholic cirrhosis, post-hepatitic cirrhosis (425 microg/l) and non-cirrhotic fibrosis (330 microg/l) had significantly higher serum YKL-40 than normal subjects (102 microg/l), patients with fatty liver (195 microg/l) or patients with viral hepatitis without fibrosis (174 microg/l). Serum YKL-40 was significantly (p<0.001) related to the degree of liver fibrosis with the highest levels in patients with moderate (466 microg/l) to severe (676 microg/l) fibrosis. Serum YKL-40 was also increased (p=0.018) in patients with slight fibrosis (270 microg/l) compared to patients without fibrosis. Immunohistochemical analysis demonstrated positive staining for YKL-40 antigen in areas with fibrosis, particularly areas with active fibrogenesis. YKL-40 staining was never found in hepatocytes.

CONCLUSIONS

Our study indicates that the increased serum YKL-40 in patients with liver disease of various degree and aetiology seems to reflect fibrosis and fibrogenesis.

YKL-40 in giant cells and macrophages from patients with giant cell arteritis

OBJECTIVE

YKL-40, a mammalian member of the family 18 glycosyl hydrolases, is secreted by activated macrophages at a late stage of differentiation. Macrophages are present in inflammation of the arterial wall and are thought to participate in the pathogenesis of giant cell arteritis (GCA). The aim of this study was to evaluate whether macrophages and giant cells of patients with GCA produce YKL-40, and whether serum YKL-40 concentrations are elevated in these patients.

METHODS

Serum YKL-40 was determined by radioimmunoassay in 19 patients with GCA and 8 patients with polymyalgia rheumatica (PMR) who were followed up prospectively during 1 year of treatment with prednisolone. Immunohistochemical staining for YKL-40 was performed in temporal artery biopsy samples that were obtained before treatment.

RESULTS

In the arteritic vessels of patients with GCA, positive staining for the YKL-40 antigen was found in CD68+ giant cells and mononuclear cells located in the media. Macrophages located in the adventitia and intima were negative for YKL-40. At the time of diagnosis, patients with GCA had an increased median serum level of YKL-40 (256 microg/liter; P<0.01) compared with healthy age-matched controls (median 118 microg/liter), and the serum level of YKL-40 decreased to normal levels during prednisolone treatment (-38% after 1 month; P<0.001). Most patients with PMR had normal serum YKL-40 levels (median 158 microg/liter) and had no changes in the serum YKL-40 levels during prednisolone treatment. The observed changes in serum YKL-40 did not always parallel the changes in serum C-reactive protein levels and erythrocyte sedimentation rate during the 1-year study period.

CONCLUSION

YKL-40 is found in CD68+ giant cells and mononuclear cells in the media of arteritic vessels of patients with GCA, and the concentration of serum YKL-40 may reflect the local activity of these cells in the inflamed artery.

YKL-40 in giant cells and macrophages from patients with giant cell arteritis

OBJECTIVE

YKL-40, a mammalian member of the family 18 glycosyl hydrolases, is secreted by activated macrophages at a late stage of differentiation. Macrophages are present in inflammation of the arterial wall and are thought to participate in the pathogenesis of giant cell arteritis (GCA). The aim of this study was to evaluate whether macrophages and giant cells of patients with GCA produce YKL-40, and whether serum YKL-40 concentrations are elevated in these patients.

METHODS

Serum YKL-40 was determined by radioimmunoassay in 19 patients with GCA and 8 patients with polymyalgia rheumatica (PMR) who were followed up prospectively during 1 year of treatment with prednisolone. Immunohistochemical staining for YKL-40 was performed in temporal artery biopsy samples that were obtained before treatment.

RESULTS

In the arteritic vessels of patients with GCA, positive staining for the YKL-40 antigen was found in CD68+ giant cells and mononuclear cells located in the media. Macrophages located in the adventitia and intima were negative for YKL-40. At the time of diagnosis, patients with GCA had an increased median serum level of YKL-40 (256 microg/liter; P<0.01) compared with healthy age-matched controls (median 118 microg/liter), and the serum level of YKL-40 decreased to normal levels during prednisolone treatment (-38% after 1 month; P<0.001). Most patients with PMR had normal serum YKL-40 levels (median 158 microg/liter) and had no changes in the serum YKL-40 levels during prednisolone treatment. The observed changes in serum YKL-40 did not always parallel the changes in serum C-reactive protein levels and erythrocyte sedimentation rate during the 1-year study period.

CONCLUSION

YKL-40 is found in CD68+ giant cells and mononuclear cells in the media of arteritic vessels of patients with GCA, and the concentration of serum YKL-40 may reflect the local activity of these cells in the inflamed artery.

Pulmonary damage after modest exposure to zinc chloride smoke

Thirteen soldiers (11 men and two women) were exposed to zinc chloride smoke (ZCS) during a combat exercise. Even though their initial symptoms were modest, a prolonged follow up with lung function testing and blood samples was undertaken due to previous cases with fatal outcome after exposure to ZCS. Four weeks after exposure there were statistically significant declines from baseline values in lung diffusion capacity and total lung capacity of 16.2% and 4.3%, respectively. At the same time plasma levels of fibrinogen and zinc were significantly elevated, though mainly within the normal range. All variables showed a tendency towards normalization at follow up 8 weeks and 6 months after exposure. These findings indicate an unexpected quantifiable damage to lung parenchyma with a remarkable delay after modest exposure to zinc chloride smoke despite sparse initial symptoms. Exposure to high concentrations of ZCS may induce adult respiratory distress syndrome (ARDS) after a symptom free period of up to 12 days from exposure. Even though none of the soldiers in the present study developed ARDS the assessment of lung diffusion capacity and acute phase reactants is proposed as a supplement when monitoring patients after exposure to ZCS.

YKL-40, a matrix protein of specific granules in neutrophils, is elevated in serum of patients with community-acquired pneumonia requiring hospitalization

The serum concentration of YKL-40, a matrix protein of specific granules in neutrophils, was determined by RIA in 90 patients hospitalized with pneumonia of suspected bacterial origin. Of these, 64 were followed prospectively during antibiotic treatment with blood samples taken on day 0 (on admission and the start of treatment) and on days 1, 3, 5, 7, 10, and 21. Serum YKL-40 at admission was increased in patients with Streptococcus pneumoniae pneumonia (median, 893 microgram/L; 95% confidence interval [CI], 704-1560), compared with healthy subjects (median, 102 microgram/L; 95% CI, 64-247 microgram/L; P<.001) and in patients with pneumonia of unknown etiology (median, 448 microgram/L; 95% CI, 334-700; P<.05). Peak YKL-40 serum values were observed on day 1 and thereafter declined steeply to almost normal by day 3. During the first 10 days, there was a close relation between serum YKL-40 and markers of specific granules of neutrophils (serum lactoferrin and neutrophil gelatinase-associated lipocalin), which suggests that serum YKL-40 reflects exocytosis of specific granules of neutrophils in persons with acute bacterial pneumonia.

Serum YKL-40 concentrations in patients with rheumatoid arthritis: relation to disease activity

OBJECTIVE

YKL-40, also called human cartilage glycoprotein-39, is secreted by chondrocytes, synovial cells, macrophages and neutrophils. Studies have shown that YKL-40 is an autoantigen in rheumatoid arthritis (RA). We evaluated whether serum YKL-40 was related to disease activity in patients with RA.

METHODS

Serum YKL-40 was determined by radioimmunoassay in 156 patients with RA during a 1 yr longitudinal study.

RESULTS

Serum YKL-40 was increased in 54% of the patients with clinically active disease. Patients with clinically active disease initially who became inactive after 12 months had a significant decrease in serum YKL-40 (-30%, P < 0.002) and patients who changed from inactive to active disease had an increase in serum YKL-40. Patients who remained active had unchanged serum YKL-40 during the study. Serum YKL-40 decreased rapidly (-24% after 7 days, P < 0.01) during prednisolone therapy, and more slowly in patients treated with methotrexate only (-15% after 60 days, P < 0.01). Patients with early RA (disease duration < 3 yr, n = 50) and a persistently elevated serum YKL-40 were at risk of radiological disease progression as determined by Larsen score.

CONCLUSION

Serum YKL-40 varies according to disease activity in RA, but provides in some respect information different from conventional markers. Our previous studies are consistent with a local release of YKL-40 in the arthritic joint followed by a secondary increase in serum YKL-40. YKL-40 may prove to be a new tool for the study of disease activity and pathophysiology of RA.

The distribution of YKL-40 in osteoarthritic and normal human articular cartilage

YKL-40, also called human cartilage glycoprotein-39, is a major secretory protein of human chondrocytes in cell culture. YKL-40 mRNA is expressed by cartilage from patients with rheumatoid arthritis, but is not detectable in normal human cartilage. The aim was to investigate the distribution of YKL-40 in osteoarthritic (n=9) and macroscopically normal (n=5) human articular cartilage, collected from 12 pre-selected areas of the femoral head, to discover a potential role for YKL-40 in cartilage remodelling in osteoarthritis. Immunohistochemical analysis showed that YKL-40 staining was found in chondrocytes of osteoarthritic cartilage mainly in the superficial and middle zone of the cartilage rather than the deep zone. There was a tendency for high number of YKL-40 positive chondrocytes in areas of the femoral head with a considerable biomechanical load. The number of chondrocytes with a positive staining for YKL-40 was in general low in normal cartilage. The present findings, together with previous observations, suggests that YKL-40 may be of importance in cartilage remodelling/degradation of osteoarthritic joints.

Serum YKL-40 and colorectal cancer

YKL-40 is a mammalian member of the chitinase protein family. Although the function of YKL-40 is unknown, the pattern of its expression suggests a function in remodelling or degradation of extracellular matrix. High serum YKL-40 has been found in patients with recurrent breast cancer and has been related to short survival. In the present study we analysed YKL-40 in preoperative sera from patients with colorectal cancer and evaluated its relation to survival. Serum YKL-40 was determined by RIA in 603 patients. Survival after operation was registered, and median follow-up time was 61 months. Three hundred and forty patients died. Sixteen per cent of the patients with Dukes' A, 26% with Dukes' B, 19% with Dukes' C and 39% with Dukes' D had high serum YKL-40 levels (adjusted for age). Analysis of serum YKL-40 as a continuous variable showed an association between increased serum YKL-40 and short survival (P < 0.0001). Patients with high preoperative serum YKL-40 concentration had significantly shorter survival than patients with normal YKL-40 (HR = 1.7; 95% CI: 1.3-2.1, P < 0.0001). Multivariate Cox analysis including serum YKL-40, serum CEA, Dukes' stage, age and gender showed that high YKL-40 was an independent prognostic variable for short survival (HR = 1.4; 95% CI: 1.1-1.8, P = 0.007). These results suggest that YKL-40 may play an important role in tumour invasion.

YKL-40, a mammalian member of the chitinase family, is a matrix protein of specific granules in human neutrophils

YKL-40, also called human cartilage glycoprotein-39 (HC gp-39), is a member of family 18 glycosyl hydrolases. YKL-40 is secreted by chondrocytes, synovial cells, and macrophages, and recently it has been reported that YKL-40 has a role as an autoantigen in rheumatoid arthritis (RA). The function of YKL-40 is unknown, but the pattern of its expression in normal and disease states suggests that it could function in remodeling or degradation of the extracellular matrix. High levels of YKL-40 are found in synovial fluid from patients with active RA. Neutrophils are abundant in synovial fluid of patients with RA, and the cells are assumed to play a role in joint destruction in that disorder. Therefore, we examined whether neutrophils are a source of YKL-40. YKL-40 was found to colocalize and comobilize with lactoferrin (the most abundant protein of specific granules) but not with gelatinase in subcellular fractionation studies on stimulated and unstimulated neutrophils. Double-labeling immunoelectron microscopy confirmed the colocalization of YKL-40 and lactoferrin in specific granules of neutrophils. Immunohistochemistry on bone marrow cells showed that neutrophil precursors begin to synthesize YKL-40 at the myelocyte-metamyelocyte stage, the stage of maturation at which other specific granule proteins are formed. Assuming that YKL-40 has a role as an autoantigen in RA by inducing T cell-mediated autoimmune response, YKL-40 released from neutrophils in the inflamed joint could be essential for this response. In RA and other inflammatory diseases, YKL-40 released from specific granules of neutrophils may be involved in tissue remodeling or degradation.

Plasma YKL-40: a new potential marker of fibrosis in patients with alcoholic cirrhosis?

BACKGROUND

YKL-40 (human cartilage glycoprotein-39, or 38-kDa heparin-binding glycoprotein) is a mammalian member of a protein family that includes bacterial chitinases. YKL-40 mRNA is expressed by human liver and may play a role in tissue remodelling. The aims were to assess whether circulating YKL-40 is released or extracted in the hepatosplanchnic system and to localize YKL-40 in liver tissue.

METHODS

Plasma YKL-40 was determined by radioimmunoassay in 25 patients with liver diseases (alcoholic cirrhosis (n = 20), chronic active hepatitis (n = 2), cirrhosis of unknown aetiology (n = 2), and fatty liver (n = 1) and in 18 subjects with normal liver function during a haemodynamic investigation with catheterization of liver vein and the femoral artery. Immunohistochemical studies of the localization of YKL-40 in cryostal liver biopsy specimens were obtained from eight other patients with alcoholic liver disease.

RESULTS

Plasma YKL-40 was significantly increased in patients with alcoholic cirrhosis (median, 523 micrograms/l; P < 0.001) compared with controls (106 micrograms/l), and plasma YKL-40 in the hepatic vein was higher (P < 0.01) than that of the artery in both the patients and controls, showing release of YKL-40 from the hepatosplanchnic area. The release rate of YKL-40 from the hepatosplanchnic area was higher in patients with liver disease than in controls (11.0 versus 2.1 micrograms/min, P < 0.05). Furthermore, the highest plasma YKL-40 levels were found in patients with a moderate or severe degree of liver fibrosis, and immunohistochemical studies showed positive staining for YKL-40 antigen in areas of the liver biopsy with fibrosis.

CONCLUSIONS

The increased plasma YKL-40 in patients with alcoholic cirrhosis may reflect the remodelling of liver fibrosis.

Serum YKL-40 levels in healthy children and adults. Comparison with serum and synovial fluid levels of YKL-40 in patients with osteoarthritis or trauma of the knee joint

YKL-40 is a recently discovered human glycoprotein which is related in amino acid sequence to the chitinase protein family. YKL-40 is a major secretory protein of human chondrocytes and synoviocytes, and could play a role in tissue remodelling. The aim of the study was to establish the serum YKL-40 level in normal subjects and to evaluate serum YKL-40 as a marker for osteoarthritis. Serum YKL-40 was 80 micrograms/l in healthy children (n = 476) and 102 micrograms/l in healthy adults (n = 260). No age or sex differences were found in serum YKL-40 in subjects younger than 70 yr, but thereafter serum YKL-40 increased significantly. Patients with late-stage osteoarthritis of the knee (n = 37) had significantly higher serum YKL-40 (1.5-fold; P < 0.01) compared to healthy age-matched subjects, whereas patients with early-stage osteoarthritis of the knee or recent torn cruciate ligaments or menisci did not have elevated serum YKL-40. The level of YKL-40 in serum and synovial fluid correlated significantly, and 10-fold higher values were found in synovial fluid. YKL-40 levels in serum and synovial fluid of patients with acute severe synovial inflammation were significantly higher (P < 0.05-P < 0.001) than those in patients with no, light or moderate synovitis of the knee joint. Furthermore, YKL-40 correlated significantly (P < 0.01) with the amino-terminal propeptide of type III procollagen, but not with serum C-reactive protein. Our data indicate that YKL-40 in synovial fluid and serum may reflect human articular cartilage degradation and the degree of synovial inflammation in the knee joint.

Serum YKL-40: a new potential marker of prognosis and location of metastases of patients with recurrent breast cancer

YKL-40 is a recently discovered glycoprotein which is related in amino acid sequence to the chitinase protein family, but has no chitinase activity. Although the function of YKL-40 is presently unknown, the pattern of its expression by some tissues suggests that YKL-40 could function in tissue remodelling. The diagnostic features and relation to survival of serum YKL-40 have not been examined previously in human malignancies. In the present study YKL-40 was measured in serum obtained from 60 patients at the time that breast cancer recurrence was suspected. The median serum YKL-40 in patients with visceral or bone metastases was 328 and 157 micrograms/l, respectively and significantly higher compared to controls (99 micrograms/l, P < 0.001). Kaplan-Meier survival curves demonstrated that survival rates after 18 months were 24% for patients with high serum YKL-40 (> 207 micrograms/l = the 95 percentile of controls) and 60% for patients with normal serum YKL-40. The significance of the difference between the shorter survival of patients with high serum YKL-40 and the longer survival of patients with normal serum YKL-40 was high (P < 0.0009). When evaluated with other prognostic factors of survival after recurrence of breast cancer, serum YKL-40 and serum lactate dehydrogenase (LDH) were the most significant independent factors. The results indicate that determination of serum YKL-40 can be used as a prognostic marker related to the extent of disease and survival of patients with recurrence of breast cancer. In addition, the serum YKL-40 level may be of value in the follow-up of patients with breast cancer and in evaluating potential metastatic spread.

Tissue kinetics, ion transport, and recruitment of mitochondria-rich cells in the skin of the toad (Bufo bufo) in response to exposure to distilled water

Mitochondria-rich cells (MRC) of the amphibian epidermis are responsible for active chloride uptake at low external salinity, and new MRCs are recruited in response to exposure to distilled (deionized) water. The time-course of this recruitment, the tissue kinetics and ion transport have been studied in toads (Bufo bufo) immediately before, and after 2,7, and 14 days exposure to distilled water. General epidermal structure was not affected. However, the numbers of MRCs per mm2 (DMRC) increased throughout the experiment as revealed by staining of epidermal sheets with AgNO3 (Ag) or methylene blue (MB). Part of the increased DMRC was accounted for by an increase in MRC subpopulation(s) that stained neither with Ag nor MB. The cell birth rate (Kb) decreased and cell loss by moulting (Kd) increased without any significant change in epidermal cell pool size, indicating a reduced apoptotic rate. The increase in DMRC was accompanied by a 3-fold increase in Cl- current (ICl). At day-2 there was a transient reduction in the ICl per MRC. H+ secretion was progressively reduced during prolonged exposure to distilled water. Thus, at day-2 MRCs appeared incompletely differentiated as indicated by decreased ICl and H+ flux per MRC, and by the increased proportion of MRCs unstained by Ag or MB. Full Cl- (but not H+) transport capacity, was restored at day-7. We conclude that increased DMRC following exposure to low external Cl-, rather than being due to an increased Kb, is the combined effect of a decreased apoptotic rate and an increased rate of differentiation, where 'morphological differentiation' precedes 'functional differentiation'.