Elevated levels of interleukin-1beta-converting enzyme and caspase-cleaved cytokeratin-18 in acute myocardial infarction

Cytokeratin 18 as a Novel Biomarker in Patients with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a heart muscle disease associated with an increased risk for sudden cardiac death (SCD). Cytokeratin 18-based proteins, such as M30 and M65 antigens, are known cell-death biomarkers. M30 antigen is released from cells during apoptosis, and M65 antigen is released during cell death from any cause, such as apoptosis or necrosis. We aimed to study the expression of M30 and M65 antigens in peripheral blood obtained by 46 HCM patients and compare with 27 age- and sex-matched patients without HCM. We also investigated the CK18 expression in myocardium from postmortem HCM hearts. M30 and M65 antigens were significantly increased in the HCM vs. non-HCM group (Μ30: 338 ± 197 U/uL vs. 206 ± 166 U/uL, p = 0.003; M65: 428 ± 224 U/uL vs. 246 ± 214 U/uL, p = 0.001), and HCM patients with a higher expression of these markers (M30: 417 ± 208 vs. 271 ± 162 U/uL, p = 0.011; M65: 518 ± 242 vs. 351 ± 178 U/uL, p = 0.011) had a higher risk for SCD. In HCM, both apoptosis and necrosis are increased, but particularly necrosis (M30/M65 ratio: 0.75 ± 0.09 vs. 0.85 ± 0.02, p < 0.001). CK18 is expressed in the HCM myocardium (1.767 ± 0.412 vs. 0.537 ± 0.383, % of area, p = 0.0058). Therefore, M30 and M65 antigens may be novel biomarkers in HCM.

The effect of Remote Ischemic Preconditioning (RIPC) on myocardial injury and inflammation in patients with severe aortic valve stenosis undergoing Transcatheter Aortic Valve Replacement (TAVΙ)

BACKGROUND

Remote ischemic preconditioning (RIPC) is being evaluated as a strategy to reduce cardiac injury and inflammation in patients undergoing diverse cardiac invasive and surgical procedures. However, it is unclear whether RIPC has protective effects in patients undergoing the transfemoral- transcatheter aortic valve implantation (TF-TAVΙ) procedure.

METHODS

Between September 2013 and September 2015, 55 random consecutive patients were prospectively assigned to receive SHAM preconditioning (SHAM, 22 patients) or Remote Ischemic Preconditioning (RIPC) (4 cycles of 5 min intermittent leg ischemia and 5 min reperfusion, 33 patients) prior to TF-TAVI. The primary endpoint was to determine the serum levels of: hs-cTn-I (necrosis), CK-18 (apoptosis), and IL-1b (inflammation). Quantification was performed using commercially available ELISA kits. Patients were sampled 1-day pre TF-TAVΙ and 24-hours post TF-TAVΙ. Secondary endpoints included: total mortality, incidence of periprocedural clinical acute myocardial infarction (AMI), acute kidney injury (AKI), and stroke.

RESULTS

22 SHAM patients and 33 RIPC patients were finally analyzed. Our data revealed no significant difference in serum levels of hs-cTn-I and CK-18 among various groups. However, in the RIPC group, the increase in IL1b level was significantly lower for 24-h post TF-TAVΙ, (p < 0.01). There were no significant differences between groups in the secondary endpoints at the follow-up interval of one month. RIPC-related adverse events were not observed.

CONCLUSIONS

Our data suggest that RIPC did not exhibit significant cardiac or kidney protective effects regarding necrosis and apoptosis in patients undergoing TF-TAVΙ. However, an important anti-inflammatory effect was detected in the RIPC group.

Effect of Synbiotic and Probiotic Supplementation on Serum Levels of Endothelial Cell Adhesion Molecules in Hemodialysis Patients: a Randomized Control Study

The aim of this study was to investigate the effect of synbiotic and probiotic supplementation on serum vascular dysfunction and necrosis markers in hemodialysis (HD) patients. In this randomized, double-blind, placebo-controlled trial, 75 HD patients were randomly assigned to either the synbiotic or probiotic or placebo group. The patients in the synbiotic group received 15 g of prebiotics and 5 g probiotic powder containing Lactobacillus acidophilus strain T16 (IBRC-M10785), Bifidobacterium bifidum strain BIA-6, Bifidobacterium lactis strain BIA-6, Bifidobacterium longum strain LAF-5 (2.7 × 10⁷ CFU/g each) in sachets (n = 25), whereas the probiotic group received 5 g probiotics same to the first group with 15 g of maltodextrin powder in sachets (n = 25) and the placebo group received 20 g of maltodextrin powder in sachets (n = 25) for 12 weeks. At baseline and the end of the study, serum concentrations of soluble intercellular adhesion molecule type 1 (sICAM-1), soluble vascular cell adhesion molecule type 1 (sVCAM-1), cytokeratin 18 (CK-18) as the necrosis marker, uric acid, and phosphate levels were measured. Feces also were collected for microbiota colony counting. Serum ICAM-1 level reduced significantly in the synbiotic group after the intervention period (P = 0.02), and this reduction was significantly different in the synbiotic group in comparison to the placebo group (P = 0.03). Serum levels of VCAM-1 and CK-18 were not significantly different between the groups. However, the reduction in serum levels of VCAM-1 in the synbiotic group was significantly higher in comparison to the placebo group (P = 0.01). Multivariate linear regression analysis revealed that ∆ phosphate was the sole independent determinant of ∆ICAM-1 (P = 0 < 001). The study indicated that synbiotic supplementation reduced serum ICAM-1 level, which is a risk factor for cardiovascular diseases in HD patients, but has no effect on the necrosis marker. Trial registration: www.irct.ir (IRCT2017041233393N1).

Subacute Elevation of Plasma Level of Caspase-Cleaved Cytokeratin-18 is Associated with Hemorrhagic Transformation and Functional Outcome in Ischemic Stroke

BACKGROUND

Caspase-cleaved cytokeratin-18 (CCCK-18) is an apoptosis marker. Here, we analyzed the relationship between plasma level of CCCK-18 in the acute and subacute stage of ischemic stroke and early and late functional outcome. Besides, correlation among CCCK-18 and complications, such as hemorrhagic transformation (HT) were also explored.

METHODS

Plasma concentration of CCCK-18 was investigated in 54 patients at admission and poststroke 72 hours. HT was evaluated by CT scans on 24 poststroke hours. Outcome measures were assessed by modified Rankin scale at hospital discharge and 6-month later. Receiver operating characteristics (ROC) analysis was used to determine the best cut-off values of CCCK-18 as a predictor of unfavorable functional outcome.

RESULTS

Significantly elevated CCCK-18 level was observed at 72 hours after onset of stroke, in nonsurviving compared to surviving patients (331 ± 191 ng/L versus 251 ± 164 ng/L, P = .01). Based on ROC analysis, the cut-off value of plasma CCCK-18 levels >223 ng/L at 72 poststroke hours predicted 6-month unfavorable stroke outcome with a sensitivity of 84.4% and a specificity of 77.3% (area under the curve: .851, 95% confidence interval = .745-.955, P < .001). The rate of complications such as HT and in-hospital infection was significantly higher in patients presented with a plasma CCCK-18 level above the cut-off value.

CONCLUSIONS

The association between high serum CCCK-18 levels and unfavorable early and late stroke outcome in an unselected study population was first described here. Besides, the apoptosis marker CCCK-18 might be a predictor of further complication such as HT and in-hospital infection.

Comparative study of cardio-protective effects of zinc oxide nanoparticles and zinc sulfate in streptozotocin-induced diabetic rats

The cardio-protective effects of zinc oxide nanoparticles (Zn NPs) against diabetes-induced cardiopathy were evaluated and compared with zinc sulfate (ZnSO₄). A total of 120 Wistar rats were randomly categorized as healthy and diabetic groups. Then, the 2 groups were classified in 5 subgroups. The animals received oral supplementations containing different Zn NP (ie, doses of 1, 3, and 10mg/kg) and ZnSO₄ (30mg/kg) concentrations over 8 weeks. Blood and cardiac tissue samples were collected in the different time intervals and subjected to biochemical and histopathological analysis. Zn NPs showed dual effects, as its middle dose played protective role and recovered cardiac damages evidenced by significant reduction of serum cholesterol, HDL-cholesterol, lipoprotein (a), atherogenic index, TNF-α, cardiac MDA, B-type natriuretic peptide and caspase-3 activity. Apoptosis indices and histopathological features also were improved. However, the highest dose was found to be toxic and resulted in aggravation of the injuries. Another interesting finding is the ability of the higher doses of Zn-NPs (3 and 10mg/kg) to elevate cardiac zinc levels above the normal range in healthy animal. ZnSO₄ also helped to recuperation of the damages, but the middle dose of Zn NPs was more efficient as compared to ZnSO₄. Conclusively, Zn NPs have the potential for Zn delivery in diabetic patients.

The predictive value of M30 and oxidative stress for left ventricular remodeling in patients with anterior ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention

BACKGROUND

Left ventricular (LV) remodeling is an important pathophysiological event that develops following acute myocardial infarction and causes LV systolic dysfunction. Mechanisms such as apoptosis, necrosis, and oxidative stress play an important role in LV remodeling.

OBJECTIVES

This study aimed to determine the relationship between the development of LV remodeling and the apoptosis marker M30 in patients with anterior ST-segment elevation myocardial infarction (STEMI) who were treated with primary percutaneous coronary intervention (PCI).

MATERIALS AND METHODS

This retrospective study included 255 consecutive patients (210 men, 45 women, mean age 54.9±11.8 years) with anterior STEMI who were treated with primary PCI. Blood samples were obtained from each patient at admission and 24 h after admission for measurements of M30, M65, oxidative parameters, and biochemical parameters. Transthoracic echocardiography was performed in each patient within 24 h of infarction and 6 months after infarction. LV remodeling was defined as greater than or equal to 20% increase in end-diastolic volume 6 months after primary PCI. The patients were divided into two groups on the basis of 6 months of post-primary PCI follow-up findings: LV remodeling group and non-LV remodeling group.

RESULTS

In all, 60 patients received LV remodeling and 195 did not receive LV remodeling at 6 months after primary PCI. Total oxidative stress, M30 and M65 levels, and the oxidative stress index were significantly higher and the total antioxidant capacity and M65/M30 ratio were lower in the LV remodeling group (P<0.05, for all). Brain natriuretic peptide, M30, and oxidative stress index were independent predictors of LV remodeling (P<0.05 for all). Receiver operating characteristic curve analysis showed that the M30 cut-off value for predicting LV remodeling was 144.9 U/l (80% sensitivity and 77% specificity, P<0.001).

CONCLUSION

In patients with anterior STEMI treated with primary PCI, the apoptosis marker M30 might be useful for predicting LV remodeling and subsequent LV systolic dysfunction.

Circulating Levels of M30 and M65 Molecules in Transitional Cell Carcinoma of the Bladder and Their Relation to Tumor Progression

BACKGROUND

Various markers are suggested for diagnosis and monitoring of transitional cell carcinoma of the bladder (TCC), including cytokeratins (CKs).

OBJECTIVES

In the present study, the circulating CK18 (M65) and its caspase-cleaved form, ccCK18 (M30), have been investigated in a group of patients with TCC.

PATIENTS AND METHODS

Serum samples were obtained from 60 patients before surgical resection, among which the samples of 26 patients after resection were also included. We measured the levels of soluble M30 and M65 molecules by enzyme-linked immunosorbent assay. The relation between these markers and patients' clinical characteristics was evaluated.

RESULTS

M30 and M65 in total patient sera were 148 ± 16 U/L and 318 ± 34 U/L, respectively. A correlation existed between pre-operative M30 and M65 levels (P < 0.0001, Spearman r = 0.51). M65, but not M30, showed a significant relation to tumor stage and grade. The M65 quantity in patients with T3/T4 tumor stages (350 ± 42 U/L) was higher than that of patients with T1/T2 stages (293 ± 45U/L; P < 0.038). Patients with tumor grades III/IV also showed higher levels of M65 compared to patients with tumor grades I/II (P < 0.04). The M30:M65 ratio in all patients was 0.54 ± 0.04. There was a lower M30:M65 ratio in patients with T3/T4 stage tumors and those with tumor grades III/IV (P < 0.02). The M30 (133 ± 19 U/L) and M65 levels (240 ± 21 U/L) after surgery did not significantly differ compared to their pre-operative values. However, a correlation between the pre- and post-operative M30:M65 ratio in patients ≥ 70 years was seen (P = 0.009).

CONCLUSIONS

These data suggested a relationship of both M65 and the M30:M65 ratio to tumor progression which might imply their importance in TCC monitoring.

Plasma IL-1 receptor antagonist levels correlate with the development of non-alcoholic steatohepatitis

Aim: Nonalcoholic steatohepatitis (NASH) is a liver disease characterized by lipid accumulation and inflammation. Here, we aimed to evaluate plasma IL-1Ra as a marker for NASH and to determine whether diagnosis of NASH can be further improved by adding IL-1Ra measurements. Materials & methods: Therefore, plasma concentrations of IL-1Ra were measured from 146 subjects of a biopsy-proven NASH cohort with matched controls. Results: NASH patients had higher levels of plasma IL-1Ra compared with patients with steatosis or healthy controls. Conclusion: Our data confirm that IL-1Ra can be a useful tool in the diagnosis of hepatic inflammation and suggest that measuring plasma IL-1Ra levels in addition to ALT will improve the diagnosis for NASH at all stages of the disease.

Serum caspase-cleaved cytokeratin-18 levels and outcomes after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Cell apoptosis is involved in acute brain injury after aneurysmal subarachnoid hemorrhage (aSAH). The protein cytokeratin-18 (CK-18) is cleaved by the action of caspases during apoptosis, and the resulting fragments are released into the blood as caspase-cleaved CK (CCCK)-18. Our study examined the relationship between circulating CCCK-18 levels and long-term clinical outcomes among aSAH patients.

METHODS

We recruited 128 aSAH patients and 128 controls (matched on age and sex). Serum was collected at admission to the emergency department. Unfavorable outcome was defined as the Glasgow Outcome Score scores of 1-3. After a 6-month follow-up period, outcomes were assessed using a logistic regression analyses. The prognostic predictive values were evaluated according to receiver operating curves analysis.

RESULTS

aSAH patients had higher plasma CCCK-18 levels compared to controls (235.1 ± 86.8 U/L vs. 25.6 ± 23.4 U/L, P<0.001). CCCK-18 was independently associated with World Federation of Neurological Surgeons (WFNS) scores (t=4.460, P<0.001) and modified Fisher scores (t=3.781, P<0.001). Furthermore, CCCK-18 levels were markedly higher among patients with an unfavorable outcome and among non-survivors. CCCK-18 was yet identified as an independent prognostic predictor for mortality (odds ratio, 5.769; 95% confidence interval, 1.196-27.832; P=0.029) and unfavorable outcome (odds ratio, 4.909; 95% confidence interval, 1.521-15.838; P=0.008), as well as had similar predictive values for them compared with WFNS scores and modified Fisher scores.

CONCLUSIONS

High circulating CCCK-18 levels were associated with injury severity and a poor clinical outcome after aSAH and CCCK-18 had the potential to be a good prognostic biomarker for aSAH.

Predictive value of serum caspase-cleaved cytokeratin-18 concentrations after acute intracerebral hemorrhage

BACKGROUND

Caspase-cleaved Cytokeratin-18 (CCCK-18) is released during apoptosis. Serum CCCK-18 concentrations are associated with prognosis of some critical illness. We investigated the potential relationships between serum CCCK-18 concentrations and disease severity and long-term clinical outcomes after intracerebral hemorrhage.

METHODS

Serum CCCK-18 concentrations were determined in a total of 102 patients and 102 controls. Multivariate models were used to predict high concentration of CCCK-18 and 6-month clinical outcomes. The predictive values were evaluated based on areas under receiver operating curve.

RESULTS

Compared with controls, serum CCCK-18 concentrations were increased in patients (245.8±108.3U/l vs. 23.6±18.1U/l, P<0.001). National Institute of Health Stroke Scale scores [odds ratio (OR), 1.164; 95% confidence interval (CI), 1.027-1.320; P=0.003] and hematoma volumes (OR, 1.079; 95% CI, 1.018-1.205; P=0.008) were independent predictors of high concentration of CCCK-18. CCCK-18 was identified as an independent predictor of 6-month mortality (OR, 1.019; 95% CI, 1.010-1.038; P=0.013) and 6-month unfavorable outcome (OR, 1.017; 95% CI, 1.008-1.029; P=0.032) and possessed high predictive values.

CONCLUSION

Increased serum CCCK-18 concentrations are associated with disease severity and clinical outcomes, suggesting that CCCK represent a novel prognostic predictive biomarker after intracerebral hemorrhage.

Keratin 18 and heat-shock protein in chronic kidney disease

Chronic kidney disease (CKD) is an affliction associated with increased systemic stress and cell death. We will review the role of keratin 18 (K-18) and caspase-cleaved CK-18 (ccK-18) as markers for increased apoptosis and necrosis during renal failure progression. The importance of preventative expression of heat-shock proteins (HSPs) in response to cell stress will also be discussed. The frequent development of CKD leads to serious complications. The potential of use of K-18 and HSP as early biomarkers of renal failure will be reviewed. Also, the role of these proteins with respect to dialysis regimes and in acute ischemic kidney injury following renal transplantation will be discussed.

Assessment of circulating biomarkers for potential pharmacodynamic utility in patients with lymphoma

Purpose:

Treatment efficacy and toxicity are difficult to predict in lymphoma patients. In this study, the utility of circulating biomarkers in predicting and/or monitoring treatment efficacy/toxicity were investigated.

Patients and methods

Circulating biomarkers of cell death (nucleosomal DNA (nDNA) and cytokeratin 18 (CK18)), and circulating FLT3 ligand, a potential biomarker of myelosuppression, were assessed before and serially after standard chemotherapy in 49 patients with Hodgkin and non-Hodgkin lymphoma. Cytokeratin 18 is not expressed in lymphoma cells so is a potential biomarker of epithelial toxicity in this setting. Tumour response was assessed before and after completion of chemotherapy by 2D and 3D computed tomography radiological response.

Results:

Baseline nDNA level was significantly higher in all lymphoma subtypes compared with 61 healthy controls and was prognostic for progression-free survival in diffuse large B-cell lymphoma (DLBCL). Decreases in nDNA levels were observed in the first week after chemotherapy; in FL, early falls in nDNA predicted for long remission following therapy. In DLBCL, elevations in nDNA occurred in cases with progressive disease. Circulating CK18 increased within 48 h of chemotherapy and was significantly higher in patients experiencing epithelial toxicity graded >3 by Common Terminology for Classification of Adverse Events criteria. FLT3 ligand was elevated within 3–8 days of chemotherapy initiation and predicted those patients who subsequently developed neutropenic sepsis.

Conclusion:

These data suggest circulating biomarkers contribute useful information regarding tumour response and toxicity in patients receiving standard chemotherapy and have potential utility in the development of individualised treatment approaches in lymphoma. These biomarkers are now being tested within multicentre phase III trials to progress their qualification.

Role of the gp85/trans-sialidases in Trypanosoma cruzi tissue tropism: preferential binding of a conserved peptide motif to the vasculature in vivo

Background

Transmitted by blood-sucking insects, the unicellular parasite Trypanosoma cruzi is the causative agent of Chagas' disease, a malady manifested in a variety of symptoms from heart disease to digestive and urinary tract dysfunctions. The reasons for such organ preference have been a matter of great interest in the field, particularly because the parasite can invade nearly every cell line and it can be found in most tissues following an infection. Among the molecular factors that contribute to virulence is a large multigene family of proteins known as gp85/trans-sialidase, which participates in cell attachment and invasion. But whether these proteins also contribute to tissue homing had not yet been investigated. Here, a combination of endothelial cell immortalization and phage display techniques has been used to investigate the role of gp85/trans-sialidase in binding to the vasculature.

Methods

Bacteriophage expressing an important peptide motif (denominated FLY) common to all gp85/trans-sialidase proteins was used as a surrogate to investigate the interaction of this motif with the endothelium compartment. For that purpose phage particles were incubated with endothelial cells obtained from different organs or injected into mice intravenously and the number of phage particles bound to cells or tissues was determined. Binding of phages to intermediate filament proteins has also been studied.

Findings and Conclusions

Our data indicate that FLY interacts with the endothelium in an organ-dependent manner with significantly higher avidity for the heart vasculature. Phage display results also show that FLY interaction with intermediate filament proteins is not limited to cytokeratin 18 (CK18), which may explain the wide variety of cells infected by the parasite. This is the first time that members of the intermediate filaments in general, constituted by a large group of ubiquitously expressed proteins, have been implicated in T. cruzi cell invasion and tissue homing.

Chagas' disease, caused by the protozoon Trypanosoma cruzi, is an ailment affecting approximately 12–14 million people in Iberoamerica and is becoming increasingly important in North America and Europe as a result of migratory currents. The parasite invades mainly cells of the heart or the walls of the digestive tract. The patients with symptoms develop heart disease or gastrointestinal motor disorders. We and others have implicated the T. cruzi gp85/trans-sialidase surface protein family in the attachment of the parasite to the host cells. These proteins share a peptide motif called FLY. The involvement of FLY in parasite interaction with endothelial cells from different organs has been studied using bacteriophages expressing the FLY peptide as surrogates. We found that phages expressing FLY bind to endothelial cells in an organ dependent manner, particularly in the heart. Also, this peptide binds strongly to intermediate cell filaments, like cytokeratins and vimentin. These results indicate that FLY might be an important contributor to tissue tropism. It also supports the notion that the vasculature and the endothelial cells are important players in Chagas' disease. These data may have important implications in the pathology of Chagas' disease and novel therapeutic approaches for patients afflicted with this disease.

Increased soluble serum markers caspase-cleaved cytokeratin-18, histones, and ST2 indicate apoptotic turnover and chronic immune response in COPD

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a worldwide burden and a major cause of death. The disease is accompanied by chronic inflammation and increased cellular turnover that is partly due to an overwhelming induction of apoptosis. In this study, we hypothesized that systemic markers of apoptosis are altered in patients with mild-to-severe COPD.

MATERIALS AND METHODS

A total number of 64 patients and controls were enrolled in the study. Lung function parameters of all groups (nonsmoker, healthy smoker, COPD GOLD I&II, COPD GOLD III&IV) were evaluated at the time of inclusion. Enzyme-linked immunosorbent assays were used to quantify protein levels in serum samples.

RESULTS

Serum contents of apoptotic end-products caspase-cleaved cytokeratin-18 and histone-associated-DNA-fragments were increased in patients with COPD, whereas anti-inflammatory soluble ST2 showed a peak in patients with COPD I&II (P=0.031) compared to healthy smokers. Levels of pro-inflammatory caspase-1/ ICE correlated significantly with the number of pack years (R=0.337; P=0.007).

DISCUSSION

Our results indicate a systemic release of apoptosis-specific proteins as markers for increased cellular turnover accompanied by progression of COPD. Furthermore, soluble ST2 seems to have a critical role in the anti-inflammatory regulatory mechanism at early stages of the disease.

Serial changes in circulating M30 antigen, a biomarker of apoptosis, in patients with acute coronary syndromes: relationship with the severity of coronary artery disease

OBJECTIVES

Growing evidence has indicated the potential clinical usefulness of measuring different forms of cytokeratin 18 in patient sera (M30 antigen for apoptosis and M65 antigen for necrosis) for distinguishing different forms of cell death. Preliminary data have reported altered levels of cytokeratin 18 fragments in patients with acute coronary syndrome (ACS) and ischemic heart disease. In this study, serum levels of M30 and M65 were measured in 74 patients with ACS [including 17 cases with unstable angina and 57 patients with acute myocardial infarction (AMI)], 25 patients with stable angina, and 23 controls.

METHODS

In patients with ACS, serial measurements of M30 and M65 were obtained, and for each patient, the following values were determined: (i) values at admission, (ii) values obtained 24 h after symptom onset, and (iii) values obtained at 48 h after symptom onset. The severity of coronary atherosclerosis was expressed using the Gensini score.

RESULTS

On admission, M30 and M65 levels in ACS patients were similar to those observed in stable angina patients and control participants. In AMI patients, serum levels of M30 peaked at 24 h and declined thereafter at 48 h. Notably, serum levels of M30 measured at 24 h correlated significantly and positively with the extent of coronary artery disease as measured by the Gensini score in AMI patients (r = 0.253, P<0.05).

CONCLUSION

Serum levels of the apoptotic marker M30 peak at 24 h after AMI and reflects the extent of coronary artery disease in this patient group.

Cytokeratin 18 in plasma of patients with gastrointestinal adenocarcinoma as a biomarker of tumour response

Background:

Plasma biomarkers may be particularly useful as a predictor or early marker of clinical response to treatment in addition to radiological imaging. Cytokeratin 18 (CK18) is an epithelial-specific cytokeratin that undergoes cleavage by caspases during apoptosis. Measurement of caspase-cleaved (CK18–Asp396) or total cytokeratin 18 (CK18) from epithelial-derived tumours could be a simple, non-invasive way to monitor or predict responses to treatment.

Methods:

Soluble plasma CK18–Asp396 and CK18 were measured by ELISA from 73 patients with advanced gastrointestinal adenocarcinomas before treatment and during chemotherapy, as well as 100 healthy volunteers.

Results:

Both CK18–Asp396 and total CK18 plasma levels were significantly higher in patients compared with the healthy volunteers (P=0.015, P<0.001). The total CK18 baseline plasma levels before treatment were significantly higher (P=0.009) in patients who develop progressive disease than those who achieve partial response or stable disease and this correlation was confirmed in an independent validation set. The peak plasma levels of CK18 occurring in any cycle following treatment were also found to be associated with tumour response, but peak levels of CK18–Asp396 did not reach significance (P=0.01, and P=0.07, respectively).

Conclusion:

Plasma levels CK18 are a potential marker of tumour response in patients with advanced gastrointestinal malignancy.

Pro-inflammatory interleukin-18 and Caspase-1 serum levels in liver failure are unaffected by MARS treatment

BACKGROUND

The pro-inflammatory cytokine IL-18 and its activator Caspase-1 are involved in acute liver failure and acute-on-chronic-liver-failure. In acute liver failure and acute-on-chronic-liver-failure, the MARS system has been used to support liver function. Enhancement of IL-18, as seen in other extracorporeal-support systems like hemodialysis might thus have mitigated beneficial effects of the MARS system in acute hepatic failure.

PATIENTS AND METHODS

We measured serum concentrations of IL-18 and Caspase-1 in 10 patients with acute liver failure and 10 patients suffering from acute-on-chronic-liver-failure, who were all treated with MARS. Thirteen patients suffering from chronic hepatic failure and 15 healthy individuals served as controls. Data are given as mean with 95% CI.

RESULTS

Baseline IL-18 serum concentrations were significantly increased in acute liver failure and acute-on-chronic-liver-failure patients as compared to chronic hepatic failure (P=0.0039 and P=0.0011, respectively) and controls (P=0.0028 and P=0.0014, respectively). Caspase-1 serum concentrations were as well significantly elevated in the acute liver failure and acute-on-chronic-liver-failure groups as compared to chronic hepatic failure patients (P=0.0039 and P=0.0232, respectively) and controls P<0.0001 and P<0.0007, respectively). IL-18 and Caspase-1 did not change significantly during MARS treatment in acute liver failure and acute-on-chronic-liver-failure patients.

CONCLUSIONS

MARS had no effect on IL-18 and Caspase-1 serum concentrations in acute liver failure and acute-on-chronic-liver-failure, providing no evidence of harmful effects by the increase of these potentially hepatocidal cytokines.

Clinical evaluation of M30 and M65 ELISA cell death assays as circulating biomarkers in a drug-sensitive tumor, testicular cancer

Circulating full-length and caspase-cleaved cytokeratin 18 (CK18) are considered biomarkers of chemotherapy-induced cell death measured using a combination of the M30 and M65 ELISAs. M30 measures caspase-cleaved CK18 produced during apoptosis and M65 measures the levels of both caspase-cleaved and intact CK18, the latter of which is released from cells undergoing necrosis. Previous studies have highlighted their potential as prognostic, predictive, and pharmacological tools in the treatment of cancer. Disseminated testicular germ cell cancer (TC) is a paradigm for a chemosensitive solid malignancy of epithelial origin and has a cure rate of 80% to 90%. We conducted M30/M65 analyses on 34 patients with TC before and during treatment with bleomycin, etoposide, and cisplatin and showed that prechemotherapy serum levels of M65 and M30 antigens are correlated with established TC tumor markers lactate dehydrogenase, alpha-fetoprotein, and beta-human chorionic gonadotropin, probably reflecting tumor load. Cumulative percentage change of M65 and M30 from baseline to end of study was highest in poor prognosis patients (P < .05). Moreover, area under the curve profiles of M65 and M30 during chemotherapy mirrored dynamic profiles for lactate dehydrogenase, alpha-fetoprotein, and beta-human chorionic gonadotropin. Consequently, M65 and M30 levels appear to reflect chemotherapy-induced changes that correlate with changes in markers routinely used in the clinic for management of patients with TC. This is the first clinical study where M65 and M30 antigen levels correlate with established prognostic markers and provides impetus for their exploration in other epithelial cancers where there is a pressing need for informative circulating biomarkers.

Myocardial lipofuscin-laden lysosomes contain the apoptosis marker caspase-cleaved cytokeratin-18

BACKGROUND

Acute coronary syndrome is related to increased circulatory concentration of soluble apoptosis specific caspase-cleaved cytokeratin-18 (ccCK-18). Potential cardiac sources of this intermediate filament derivative have not been investigated to date.

MATERIALS AND METHODS

Paraffin embedded tissue of normal myocardium, and chronically damaged samples of ischaemic, congestive and hypertrophic cardiomyopathy were analysed by histology and by CK-8, CK-18, ccCK-18 immunohistochemistry (each group, n = 15). Antibody specificity of the ccCK-18 antibody M30 was checked by immunoblotting on lysed myocardium and enriched myocardial lysosomes.

RESULTS

ccCK-18 and CK-18 but not CK-8 were present in all forms of cardiomyopathy, most prominently in ischaemic cardiomyopathy while only traces were detectable immunohistochemically in normal myocardium. Weak CK-18 and strong ccCK-18 staining co-localized to lysosomes with cardiac age pigment lipofuscin. Weak staining of CK-18 was detected in the cytoplasm of coronary endothelia.

CONCLUSION

Our study reveals that cardiac lipofuscin-laden lysosomes contain ccCK-18, a marker of apoptosis and its precursor CK-18. This ccCK-18 pool might contribute to increased systemic levels of ccCK-18 in acute coronary syndrome thus monitoring myocardial damage.

Optimisation of circulating biomarkers of cell death for routine clinical use

BACKGROUND

M30 and M65 enzyme-linked immunosorbent assays detect circulating cytokeratin 18 fragments released during caspase-dependent or total cell death, respectively, and have potential as biomarkers in epithelial cancers. While these assays have been validated, their robustness for routine clinical use is unknown.

PATIENTS AND METHODS

M30 and M65 were measured in matched serum and plasma samples from 31 lung cancer patients and 18 controls.

RESULTS

Time allowable between sample acquisition and processing is critical for assays in clinical use. A 4-h delay in processing at room temperature increased M30 (P < 0.0001), an effect minimised by incubation on ice. M30 and M65 in serum were resistant to processing variations including delays. Serum and plasma measurements correlated well although M30 but not M65 was lower in serum (P < 0.0005). Less variation between duplicate assays was observed in serum. Prolonged storage (-80 degrees C) led to increased M30 (12%, 6 months; 34%, 1 year). Sample dilution in the supplied assay diluent proved non-linear, whereas dilution in donor serum or porcine plasma restored linearity up to a ratio of 1 : 6.

CONCLUSION

We present recommendations that improve the reliability of these assays for clinical use and recommend serum as the preferred matrix with data more resistant to variations in collection.