M30 ELISA Research Articles

Inducing Effect of Corylus avellana on Cytotoxic Activity in Lung and Breast Cancer Cells via Apoptosis

Turkish hazelnut (Corylus avellana L. cv Tombul) is a widely used nut in the chocolate industry and is also rich in polyphenol content, which promises anticancer effects. The anti-cancer and apoptotic effects of hazelnut leaves extracts examined on lung and breast cancer cells. Sulforhodamine B (SRB) and Adenosine 5’- triphosphate (ATP) assays were carried out for cell viability measurement. The mode of cell death was shown morphologically by the double fluorescence staining. Apoptosis was determined by performing caspase-mediated cytokeratin 18 (M30 ELISA) and western blot analysis. PARP, caspase 3, caspase 8, DR4, and GAPHD (Glyceraldehyde-3-phosphate Dehydrogenase) protein bands were visualized as markers of apoptosis. A wound healing test was employed to measure cell migration. Methanol extract of hazelnut leaf exhibited inhibition of cell growth activities in a dose-dependent manner. IC50 values were determined as 32.17 µg/ml in MCF-7, 32.16 µg/ml in MDA-MB-231, 20.40 µg/ml in A549 and 12.04 µg/ml in H1299 cells for ethanol extract while it was determined as 21.08 µg/ml in MCF-7, 40.16 µg/ml in MDA-MB-231, 22.04 µg/ml in A549 and 5.91 µg/ml in H1299 cells in methanol extract. In comparison, methanol leaf extracts were more effective in H1299 cells (IC50 value was 5.91 µg/ml).In comparison, ethanol leaf extracts were more effective in H1299 cells (IC50 value was 9.722 µg/ml). Western blot analysis demonstrated that hazelnut leaf extract treatment of cancer cells led to cell death via apoptosis and inhibited cell migration in lung and breast cancer cell lines. The cytotoxic effects of hazelnut extract on breast and lung cancer cells might be valuable and promising in elucidating cell death mechanisms for the development of new methods in cancer treatment.

Empirical identification and validation of tumor-targeting T cell receptors from circulation using autologous pancreatic tumor organoids

BackgroundTumor-specific cytotoxic T cells and T cell receptors are effective tools for cancer immunotherapy. Most efforts to identify them rely on known antigens or lymphocytes that have infiltrated into the...

Combination of Histone Deacetylase Inhibitor with Cu(II) 5,5-diethylbarbiturate Complex Induces Apoptosis in Breast Cancer Stem Cells: A Promising Novel Approach.

Cancer Stem Cells (CSCs) are a subpopulation within the tumor that play a role in the initiation, progression, recurrence, resistance to drugs and metastasis of cancer. It is well known that epigenetic changes lead to tumor formation in cancer stem cells and show drug resistance. Epigenetic modulators and /or their combination with different agents have been used in cancer therapy. In our study, we scope out the effects of a combination of a histone deacetylases inhibitor, Valproic Acid (VPA), and Cu(II) complex [Cu(barb-κN)(barb-κ2N,O)(phen-κN,N')]·H2O] on cytotoxicity/apoptosis in a stem-cell enriched population (MCF-7s) obtained from parental breast cancer cell line (MCF-7). The viability of the cells was measured by the ATP assay. Apoptosis was elucidated via the assessment of caspase-cleaved cytokeratin 18 (M30 ELISA) and a group of flow cytometry analysis (caspase 3/7 activity, phosphatidylserine translocation by annexin V-FITC assay, DNA damage and oxidative stress) and 2',7'- dichlorofluorescein diacetate staining. The VPA combined with Cu(II) complex showed anti-proliferative activity on MCF-7s cells in a doseand time-dependent manner. Treatment with a combination of 2.5 mM VPA and 3.12 μM Cu(II) complex induced oxidative stress in a time-dependent manner, as well as apoptosis evidenced by the increase in caspase 3/7 activity, positive annexin-V-FITC, and increase in M30 levels. The results suggest that the combination therapy induces apoptosis following increased oxidative stress, thereby making it a possible promising therapeutic strategy for which further analysis is required.

Palladium (II) Complex Enhances ROS-Dependent Apoptotic Effects via Autophagy Inhibition and Disruption of Multiple Signaling Pathways in Colorectal Cancer Cells.

Inhibition of autophagy is reported to be a therapeutically effective strategy in overcoming resistance that is a deadly outcome in cancer. One of the most common reasons for chemo-resistance to treatment is the patients with tumors exhibiting a KRAS mutation, which occurs in approximately 40% of colorectal cancer patients. Hence, we assessed whether a Palladium (Pd)(II) complex is a promising anticancer complex, compared to 5-fluorouracil in KRAS wt HT-29 and KRAS mutant HCT-15 cells. HCT-15 and HT-29 cells were used for colorectal cancer and Chloroquine (CQ) was used as an inhibitor of autophagy. In this context, cells were treated with Pd(II) complex and 5-FU in combination with CQ for 48h and cell viability was measured by SRB assay. Cell death mode was examined with M30 and M65 ELISA assays, using annexin V/propidium iodide. Autophagy was determined by Acridine Orange (AO) staining. Furthermore, the expressions of various autophagy and apoptosis-related proteins were evaluated with Western blotting. Luminex assay and the level of Reactive Oxygen Species (ROS) were examined. Cell viability was found to decrease in a dose-dependent manner and CQ enhanced cytotoxic effect in Pd(II) and 5-FU treated cells in colorectal cancer cells. Our data showed that inhibition of autophagic flux significantly increased intrinsic apoptosis through the activation of ROS. We showed that combinatorial treatment with CQ induced apoptosis via the caspase-dependent mitochondrial pathway. Luminex analysis revealed that the combination resulted in a down-regulation of NF-κB/AKT/CREB signaling pathways in both cell lines, however, decreased Erk1/2 protein expression was only observed after treatment with CQ combination in HCT-15 cells. We suggest that the inhibition of autophagy along with Pd(II) and 5-FU treatment has a synergistic effect on KRAS-mutant colorectal cancer cells. Autophagy inhibition by CQ promotes apoptosis via blockade of the NF-κB/AKT/CREB and activation of ROS.

Elevated serum cytokeratin-18 concentration in patients with type 2 diabetes mellitus and non-alcoholic fatty liver disease.

Serum cytokeratin-18 is believed to be a marker of hepatic cell damage. However, few studies have discussed about the serum cytokeratin-18 concentration in type 2 diabetes mellitus patients and investigated its association with non-alcoholic fatty liver disease as well as metabolic biomarkers. Healthy participants and type 2 diabetes mellitus patients were enrolled. Physical and metabolic factors were recorded, and non-alcoholic fatty liver disease was screened by abdominal ultrasound and the fatty liver index. The cytokeratin-18 concentration was detected using two commercially available immunoassay kits (M30 and M65 ELISA kit, Previa AB, Sweden). Overall, 22.8% (29/127) and 35.9% (42/117) of the participants were diagnosed with non-alcoholic fatty liver disease in the non-diabetes mellitus group and type 2 diabetes mellitus group, respectively. In the non-diabetes mellitus group and type 2 diabetes mellitus group, our result showed that participants with non-alcoholic fatty liver disease had a higher serum cytokeratin-18 M30 and cytokeratin-18 M65 concentration as compared with participants without non-alcoholic fatty liver disease. Interestingly, as compared with healthy participants without non-alcoholic fatty liver disease, our result also demonstrated that type 2 diabetes mellitus patients without non-alcoholic fatty liver disease had a higher serum cytokeratin-18 M30 (108.4 ± 66.2 vs. 87.1 ± 34.6 U/L; P = 0.038) and cytokeratin-18 M65 concentration (285.4 ± 115.3 vs. 248.5 ± 111.3 U/L; P = 0.031). The independent relationship between type 2 diabetes mellitus and cytokeratin-18 was further strengthened by the significant positive association between fasting plasma glucose and serum cytokeratin-18 concentration via multivariate regression analyses (cytokeratin-18 M30: β = 0.034, P = 0.029; cytokeratin-18 M65: β = 0.044, P = 0.002). Independent of non-alcoholic fatty liver disease, our results suggested that the cytokeratin-18 concentration is closely associated with the hyperglycaemic milieu. The association between serum cytokeratin-18 and type 2 diabetes mellitus may be worthy of further investigation.

PO-289 Dual inhibition of WNT/β-catenin signalling and histone deacetylation as a new strategy to eliminate breast cancer stem cells by augmentation of apoptosis

IntroductionEpigenetic changes play a critical role in the regulation of cancer stem cell (CSC) properties and the development of drug resistance. Modulation of histone acetylation program is closely related to differentiation and apoptosis process. CSCs, a subset of tumour cells, are responsible for disease relapse because of an acquired resistance to apoptosis and the Wnt signalling which is associated with cell survival/self-renewal and differentiation, is re-activated in these cells. Therefore, in the present study, we focused on a possible cytotoxic/apoptotic effect of the combination of niclosamide (Wnt/β-catenin pathway inhibitor) and Valproic acid (VPA, histone deacetylase inhibitor) on breast CSCs.Material and methodsThe effect of niclosamide (1 µM, 24 hour pre-treatment) and VPA (0.63–5 mM) combination on the viability of MCF-7s cells (CSCs-enriched population) were demonstrated by the ATP assay. Acetylated histone H3 levels at selected doses for the combination were assessed by ELISA. Protein levels associated with the Wnt/β-catenin signalling pathway, EMT, and histone modifications were shown by western blotting. Cell death mode was investigated via Hoechst 33342/PI double staining, M30 ELISA, real-time PCR (gene levels associated with apoptosis and autophagy) and western blotting (protein levels associated with apoptosis, autophagy and ER stress).Results and discussionsWe found that combination therapy exhibited a marked decrease in cell viability by inducing extrinsic apoptosis along with the stronger Wnt inhibition and increased histone H3 acetylation in MCF-7s cells. Furthermore, it was found that mesenchymal markers (fibronectin, N-cadherin, and ZEB1) were decreased at 72 hour and cytokeratin 18 as an epithelial marker was re-expressed in which H3K9ac and H3K4me3 were also increased. In addition, ER stress and blockade of autophagic flux have also been shown to be involved in this process.ConclusionIn conclusion, the future success of this combination approach in targeting CSCs and converted CSCs to non-CSCs may hold significant promise for successful treatment of breast cancer.

Valproic acid, a histone deacetylase inhibitor, induces apoptosis in breast cancer stem cells

Cancer stem–like cells (CSCs) are a cell subpopulation that can reinitiate tumors, resist chemotherapy, give rise to metastases and lead to disease relapse because of an acquired resistance to apoptosis. Especially, epigenetic alterations play a crucial role in the regulation of stemness and also have been implicated in the development of drug resistance. Hence, in the present study, we examined the cytotoxic and apoptotic activity of valproic acid (VPA) as an inhibitor of histone deacetylases (HDACs) against breast CSCs (BCSCs). Increased expression of stemness markers were determined by western blotting in mammospheres (MCF-7s, a cancer stem cell-enriched population) propagated from parental MCF-7 cells. Anti-growth activity of VPA was determined via ATP viability assay. The sphere formation assay (SFA) was performed to assess the inhibitory effect of VPA on the self-renewal capacity of MCF-7s cells. Acetylation of histon H3 was detected with ELISA assay. Cell death mode was performed by Hoechst dye 33342 and propidium iodide-based flouresent stainings (for pyknosis and membrane integrity), by M30 and M65 ELISA assays (for apoptosis and primary or secondary necrosis) as well as cytofluorimetric analysis (caspase 3/7 activity and annexin-V-FITC staining for early and late stage apoptosis). VPA exhibited anti-growth effect against both MCF-7 and MCF-7s cells in a dose (0.6–20 mM) and time (24, 48, 72 h) dependent manner. As expected, MCF-7s cells were found more resistant to VPA than MCF-7 cells. It was observed that VPA prevented mammosphere formation at relatively lower doses (2.5 and 5 mM) while the acetylation of histon H3 was increased. At the same doses, VPA increased the M30 levels, annexin-V-FITC positivity and caspase 3/7 activation, implying the induction of apoptosis. The secondary necrosis (late stage of apoptosis) was also evidenced by nuclear pyknosis with propidium iodide staining positivity. Taken together, inhibition of HDACs is cytotoxic to BCSCs by apoptosis. Our results suggested that targeting the epigenetic regulation of histones may be a novel approach and hold significant promise for successful treatment of breast cancer.

Enhanced cytotoxic activity of doxorubicin through the inhibition of autophagy in triple negative breast cancer cell line

BackgroundThe outcome of triple negative breast cancer is still poor and requires improvement with better therapy options. Autophagy has recently been shown to play a role in anticancer drug resistance. Therefore, we investigated if the effectiveness of doxorubicin was augmented by the inhibition of autophagy. MethodsMDA-MB-231 was used as a model cell line for triple negative breast cancer and 3-methyladenine was used as an inhibitor of autophagy. Cells were treated with 0.46–1.84μM doxorubicin and 2.5–10μM 3-methyladenine for 48h. Cell death mode was examined with M30 and M65 ELISA assays. ROS level and LDH activity was examined and the cellular acidic compartment of cells was monitored by acridine orange staining. The expression of various autophagy and apoptosis related proteins/genes were evaluated with Western blotting and RT-qPCR respectively. ResultsSynergism was observed between the compounds (CI value<1.0). RT-qPCR analysis revealed that the combination resulted in a down-regulation of autophagy-related genes. Moreover, the combination resulted in a different cell death modality, upregulating necroptosis-related genes. This suggests that the mode of cell death may switch from apoptosis to necroptosis, which is a more severe form of cell death, when autophagy is inhibited. These results were further confirmed at protein level by Western blotting. ConclusionInhibition of autophagy seems to sensitize triple negative breast cancer cells to doxorubicin, warranting further in vivo studies for the proof of this concept. General significanceAutophagy has a key role in drug resistance in MDA-MB-231 cells. Therefore combinatorial approaches may effectively overcome resistance.

The miR-21/PTEN/Akt signaling pathway is involved in the anti-tumoral effects of zoledronic acid in human breast cancer cell lines.

Preclinical data indicate a direct anti-tumor effect of zoledronic acid (ZA) outside the skeleton, but its molecular mechanism is still not completely clarified. The aim of this study was to investigate the anti-cancer effects of ZA in human breast cancer cell lines, suggesting that they may in part be mediated via the miR-21/PTEN/Akt signaling pathway. The effect of ZA on cell viability was measured by MTT assay, and cell death induction was analyzed using either a double AO/EtBr staining and M30 ELISA assay. A Proteome Profiler Human Apoptosis Array was executed to evaluate the molecular basis of ZA-induced apoptosis. Cell cycle analysis was executed by flow cytometry. The effect of ZA on miR-21 expression was quantified by qRT-PCR, and the amount of PTEN protein and its targets were analyzed by Western blot. ZA inhibited cell growth in a concentration- and time-dependent manner, through the activation of cell death pathways and arrest of cell cycle progression. ZA downregulated the expression of miR-21, resulting in dephosphorilation of Akt and Bad and in a significant increase of p21 and p27 proteins expression. These results were observed also in MDA-MB-231 cells, commonly used as an experimental model of bone metastasis of breast cancer. This study revealed, for the first time, an involvement of the miR-21/PTEN/Akt signaling pathway in the mechanism of ZA anti-cancer actions in breast cancer cells. We would like to underline that this pathway is present both in the hormone responsive BC cell line (MCF-7) as well as in a triple negative cell line (MDA-MB-231). Taken together these results reinforce the use of ZA in clinical practice, suggesting the role of miR-21 as a possible mediator of its therapeutic efficacy.

Addition of niclosamide to palladium(II) saccharinate complex of terpyridine results in enhanced cytotoxic activity inducing apoptosis on cancer stem cells of breast cancer

Wnt signaling is one of the core signaling pathways of cancer stem cells (CSCs). It is re-activated in CSCs and plays essential role in the survival, self-renewal and proliferation of these cells. Therefore, we aimed to evaluate the cytotoxic effects of palladium(II) complex which is formulated as [PdCl(terpy)](sac)2H2O and its combination with niclosamide which is an inhibitor of Wnt signaling pathway associated with breast cancer stem cells. Characteristic cell surface markers (CD44+/CD24−) were determined by flow cytometry in CSCs. ATP viability assay was used to determine the cytotoxic activity. The mode of cell death was evaluated morphologically using fluorescence microscopy and biochemically using M30 ELISA assay as well as performing qPCR. Our study demonstrated that the combination of niclosamide (1.5μM) and Pd(II) complex (12.5, 25 and 50μM) at 48h has enhanced cytotoxic activity resulted from the induction of apoptosis (indicated by the presence of pyknotic nuclei, increments in M30 and over expression of proapoptotic genes of TNFRSF10A and FAS). Importantly, the addition of niclosamide resulted in the suppression of autophagy (proved by the decrease in ATG5 gene levels) that might have contributed to the enhanced cytotoxicity. In conclusion, the application of this combination may be regarded as a novel and effective approach for the treatment of breast cancer due to its promising cytotoxic effect on cancer stem cells that cause recurrence of the disease.

Serum cell death biomarkers for prediction of liver fibrosis and poor prognosis in primary biliary cirrhosis.

The development of simple, noninvasive markers of liver fibrosis is urgently needed for primary biliary cirrhosis (PBC). This study examined the ability of several serum biomarkers of cell death to estimate fibrosis and prognosis in PBC. A cohort of 130 patients with biopsy-proven PBC and 90 healthy subjects were enrolled. We assessed the utility of the M30 ELISA, which detects caspase-cleaved cytokeratin-18 (CK-18) fragments and is representative of apoptotic cell death, as well as the M65 and newly developed M65 Epideath (M65ED) ELISAs, which detect total CK-18 as indicators of overall cell death, in predicting clinically relevant fibrosis stage. All 3 cell death biomarkers were significantly higher in patients with PBC than in healthy controls and were significantly correlated with fibrosis stage. The areas under the receiver operating characteristic curve for the M65 and M65ED assays for differentiation among significant fibrosis, severe fibrosis, and cirrhosis were 0.66 and 0.76, 0.66 and 0.73, and 0.74 and 0.82, respectively. In multivariate analysis, high M65ED (hazard ratio 6.13; 95% confidence interval 1.18–31.69; P = 0.031) and severe fibrosis (hazard ratio 7.45; 95% confidence interval 1.82–30.51; P = 0.005) were independently associated with liver-related death, transplantation, or decompensation. High serum M65ED was also significantly associated with poor outcome in PBC (log-rank test; P = 0.001). Noninvasive cell death biomarkers appear to be clinically useful in predicting fibrosis in PBC. Moreover, the M65ED assay may represent a new surrogate marker of adverse disease outcome.

Circulating biomarkers in hepatocellular carcinoma

Our aims are to determine levels of circulating cellular and protein biomarkers in hepatocellular carcinoma (HCC) patients and to analyse any relationships with clinical parameters. Fifty-four consenting patients were recruited. Circulating tumour cells (CTCs) were enumerated (by CellSearch) and characterised via filtration [by isolation by size of epithelial tumour cells (ISET)] with downstream immunohistochemistry (IHC). Glypican-3 (GPC3) expression in tumour biopsies and CTCs (by IHC) was compared, and levels of circulating caspase-cleaved and full-length cytokeratin 18 (CK18, measured using M30 and M65 ELISAs) were examined as a putative prognostic factor and marker of tumour burden. CTCs were identified in 14 out of 50 (28%) patients by CellSearch and in 19 out of 19 (100%) patients by ISET. The presence of GPC3-positive CTCs by ISET was 100% concordant with the presence of GPC3-positive cells in the original tumour (n = 5). No statistically significant correlations were observed between CTC number and clinical characteristics, although trends were noted between CTC subtypes, Child-Pugh score and tumour node metastasis stage. Serum M30 and M65 levels (as continuous variables) significantly correlated with overall survival (OS) in a univariate analysis (p = 0.003 and p < 0.001, respectively); M65 levels remained statistically significant in a multivariate analysis (p = 0.029). This is the first study to detect GPC3-positive CTCs in HCC, important for drug development with this target. The significant association of circulating CK18 with OS in HCC further exemplifies the utility of circulating biomarkers in cancer.

Use of monitoring levels of soluble forms of cytokeratin 18 in the urine of patients with superficial bladder cancer following intravesical Ad-IFNα/Syn3 treatment in a phase l study

A phase l study using intravesical Ad-IFNα/Syn3 for patients with BCG resistant superficial bladder cancer showed a complete remission (CR) of 43% at 90 days after treatment with high levels of IFNα being produced. Ad-IFNα kills bladder cancer cells by two apoptotic and one necrotic mechanism that can be measured by soluble forms of cytokeratin 18 (CK 18) using M30 and M65 ELISAs, assays for caspase –cleaved (apoptotic) and uncleaved (necrotic) cell death, respectively. Therefore we determined whether M30 and M65 levels in the urine after treatment could document all three mechanisms of cancer cell kill and also predict having a CR. High levels of both M30 and M65 were found in all patients within 24 hours after treatment with all three types of cancer cell death occuring. Moreover, the return of both M30 and M65 levels in the urine to normal levels within 5 days or more after treatment was strongly associated with obtaining a CR (p=0.003). This is the first time that such assays have been used to study response to therapy in the urine of patients with bladder cancer and in the future may prove valuable in predicting clinical outcome.

Evaluation of cell death mechanisms induced by the vascular disrupting agent OXi4503 during a phase I clinical trial

Background:OXi4503 is a tubulin-binding vascular disrupting agent that has recently completed a Cancer Research UK-sponsored phase I trial. Preclinical studies demonstrated early drug-induced apoptosis in tumour endothelial cells at 1–3 h and secondary tumour cell necrosis between 6 and 72 h.Methods:To capture both possible outcomes of OXi4503 treatment on cell death, plasma samples for analysis by M30 and M65 ELISAs, which measure different circulating forms of cytokeratin 18 as biomarkers of apoptosis and necrosis, respectively, were collected from patients entered into the trial at early (4/6 h) and later time points (24 h, day 8 and day 15).Results:OXi4503 induced a selective dose-dependent elevation in M30 antigen levels (apoptosis) at 4/6 h and a similar elevation in M65 antigen levels at 24 h (necrosis) consistent with its preclinical cell death profile. For the purposes of investigating potential biomarker relationships to patient characteristics, the trial population was divided into three groups based on radiological and clinical response: (a) early progression, (b) progressive disease and (c) stable disease (SD)/partial response. A significant increase in antigen concentrations was measured by M65 at 24 h in the SD group compared with the two other groups (P=0.015, mean increase 30.9%).Conclusion:These results provide pharmacodynamic evidence of drug mechanism of action in cancer patients and highlight the M65 ELISA as a potentially useful biomarker assay of response to OXi4503.

P4-16-03: Proof of the Anti-Tumour Effect of Zoledronic Acid (ZA) in Naive Bone-Only Metastatic and Locally Advanced Breast Cancer: Results from the Biological Window Therapy.

Abstract Background: Pre-clinical studies have demonstrated an anti-tumour activity of ZA in several cancers. However, the clinical evidence of the ZA anti-tumour effect is still uncertain. Our study aimed to prove that ZA has anti-tumour activity administered alone as a biological window of 14 days therapy on naïve bone-only metastatic and locally advanced breast cancer. Material and Methods: 27 patients with locally advanced breast cancer (Group 1) and 12 patients at their first relapse with bone metastasis only (Group 2) received 4 mg single dose of ZA before starting with any treatment. In Group 1, Ki67 expression was evaluated in tumour specimens obtained before and after ZA administration (basal, day 14). In Group 2, circulating tumour cells (CTCs) were evaluated at baseline, 48 hrs and day 14. In Group 1 and 2, the apoptosis and necrosis of tumour cells were tested on blood samples by M30 and M65 ELISA assay respectively. Parallel, the anti-antitumor activity of ZA, given at the dose of 250 mg/mouse every 4 days for 6 cycles, in MDA-Mb-231 bearing mice was evaluated. Results: A significant reduction of Ki67 expression after 14 days (mean, 25.33% to 21.78%; p=0.035) was observed in Group 1. In Group 2, we detected a significant reduction of CTC number after 48 hrs (median, 16 to 7; p=0.045), followed by a tendency to increase on day 14 (p=0.093). The M30/M65 analysis performed on paired blood samples in Group 2 showed after 14 days a significant increase in M65 (median, 97 to 112 U/L; p=0.018), more accentuated than the concomitant increase in M30 (p=0.308). In MDA-MB-231 bearing mice, ZA treatment caused a significant inhibition of tumor growth. Conclusions: These results are the first prospective clinical data showing a direct anti-tumour effect (either on the tumour or on CTCs) of ZA, confirming the in vitro data. By directly affecting the proliferation, ZA could have an anti-tumour effect via induction of necrosis, suggesting its possible use in combination with conventional oncologic treatments of breast cancer. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-16-03.

The oxidant/antioxidant status and cell death mode in oral squamous cell carcinoma

Objective. Oxidative stress and imbalance in the oxidant/antioxidant system have a critical role in carcinogenesis by affecting necrosis and apoptosis. The aim of this study is to evaluate the oxidant/antioxidant status and cell death modes in patients with oral squamous cell carcinoma (OSCC). Materials and methods. Twenty-nine patients with OSCC and 29 control subjects were included in the study. The levels of malondialdehyde (MDA), advanced oxidation protein products (AOPP) and ferric reducing antioxidant power (FRAP) were determined in plasma samples of all subjects. The necrotic and apoptotic cell death modes were evaluated with M65 ELISA and M30 ELISA, respectively. Results. MDA and AOPP values as oxidative stress markers were higher in patients with OSCC than in the control group. FRAP values evaluating plasma antioxidant status increased in OSCC patients. M65 and M30 levels indicating necrosis and apoptosis were significantly higher in OSCC patients compared to controls. There were significant correlations between MDA, AOPP and FRAP; M65 and M30 values. Conclusions. The elevated levels of oxidative stress markers together with the increase of antioxidant capacity and the presence of a strong correlation between MDA, AOPP and FRAP suggest an activation of antioxidant defense against accentuated oxidative stress determined in OSCC. Enhanced oxidation of lipids and proteins may cause decomposition of cell membranes with subsequent leakage of cytoskeletal cytokeratins as CK18 and caspase-cleaved CK18 (evaluated as M65 and M30, respectively) in the circulation, suggesting that both cell death modes are affected in OSCC.

Optimization of Circulating Biomarkers of Obatoclax-Induced Cell Death in Patients with Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive disease in which, after initial sensitivity to platinum/etoposide chemotherapy, patients frequently relapse with drug-resistant disease. Deregulation of the Bcl-2 pathway is implicated in the pathogenesis of SCLC, and early phase studies of Bcl-2 inhibitors have been initiated in SCLC. Obatoclax is a small-molecule drug designed to target the antiapoptotic Bcl-2 family members to a proapoptotic effect. Preclinical studies were conducted to clarify the kinetics of obatoclax-induced apoptosis in a panel of SCLC cell lines to assist with the interpretation of biomarker data generated during early phase clinical trials. In vitro, obatoclax was synergistic with cisplatin and etoposide, and “priming” cells with obatoclax before the cytotoxics maximized tumor cell death. Peak levels of apoptosis, reflected by cleaved cytokeratin 18 (CK18) levels (M30 ELISA) and caspase activity (SR-DEVD-FMK), occurred 24 hours after obatoclax treatment. A phase 1b-2 trial of obatoclax administered using two infusion regimens in combination with carboplatin and etoposide has been completed in previously untreated patients with extensive-stage SCLC. Circulating pharmacodynamic biomarkers of cell death, full-length and/or cleaved CK18, and oligonucleosomal DNA were studied in the phase 1b trial. All SCLC patients classified as “responders” after two cycles of treatment showed significantly increased levels of full-length and cleaved CK18 (M65 ELISA) on day 3 of study. However, the preclinical data and the absence of a peak in circulating caspase-cleaved CK18 in trial patients suggest suboptimal timing of blood sampling, which will need refinement in future trials incorporating obatoclax.

Application of the β-expectation tolerance interval to method validation of the M30 and M65 ELISA cell death biomarker assays

Method validation should focus on demonstrating that an assay is fit for its intended purpose. We have applied the β-expectation tolerance interval – a statistical approach that predicts the accuracy of assay measurements in the future – to the validation of two different cell death biomarker assays, the M30 and M65 ELISAs. A meta-analysis was conducted on a total of 57 different M30 and M65 assays run over a 2 year period. All code utilised in calculations was developed using MATLAB. The optimal fit to the calibration curve for the M30 assay was shown to be a quartic curve which yielded a β-expectation tolerance interval of +20.5% and −23.6% at β = 95% over a wide range of QC standards (88–810 U/L). However, such a fit required at least 7 points to avoid problems with over fitting. A linear fit to the M65 calibration curve normally produced a tolerance interval of less than ±20%, however, marked inter-batch variations were evident. Amelioration of batch to batch variations was accomplished by fitting M65 calibration data preferably to a 4-parameter logistic function or a cubic spline. The minimum number of QC replicates and different assays required to produce reliable accuracy profiles was determined. The β-expectation tolerance interval approach has resulted in further optimisation of the M30 and M65 ELISAs as biomarker assays that should translate into greater accuracy in results generated from clinical trials samples.

Different cell death mechanisms are triggered by acute or chronic right heart failure-induced liver failure

Background and Aims: Heart failure is a major issue in cardiologic patients and surgical interventions which can lead to liver failure (LF). The prognosis of LF due to right heart failure (RHF) depends on various factors like age of the patient, comorbidities, BMI and amount of cell death within the liver. However, course of liver failure and prognosis are hard to predict. The cytokeratin-18 (CK18) epitopes M65 and M30 are reported to distinguish between overall (necrotic) and apoptotic cell death, respectively. We investigated whether these cell death markers predict outcome of patients with RHF-induced LF and which cell death mechanism is predominant in each group. Methods: In a prospective study, 18 patients with LF on acute right heart failure (ARHF) and 23 patients with chronic right heart failure (CRHF) were included. Demographic and clinical parameters of the patients were collected and CK18/M65 and M30 ELISA was performed. M65 and M30 levels were correlated with outcome of liver failure, patient age and cause of liver failure. Results: Serum M65, representing overall cell death, in patients with ARHF-induced LF was significantly higher than in CRHF (19976.44±3364.63U/ml vs. 1283.29±138.43U/ml, p&lt;0.0001). Absolute M30 (as marker of apoptosis) was also higher in patients with liver affection caused by ARHF as opposed to CRHF (3956.32±1147.97U/ml vs. 642.25±41.82U/ml, p=0.009). In contrast the M30/M65 ratio was significantly higher in CRHF than in ARHF patients (0.54±0.04 vs. 0.22±0.04, p&lt;0.0001), indicating a greater contribution of apoptotic cell death in CRHF. Conclusions: The ratio of CK18 M30/M65 is a potential marker to discriminate between ARHF- induced and CRHF-induced liver failure and could probably be employed to predict outcome in patients with ARHF-induced LF.

Cytokeratin 18-based modification of the MELD score improves prediction of spontaneous survival after acute liver injury

Predicting the probability of patients with acute liver failure (ALF) to recover spontaneously is of major clinical importance. As apoptotic and necrotic cell death are crucial in the pathogenesis of ALF, we determined whether selected cell-death markers predict outcome of patients with ALF and/or discriminate between etiologies. In a prospective study (11/2006-06/2009), 68 ALF patients were recruited consecutively. Data were collected over four weeks or until discharge, death or LTx, including CK18/M65 and M30 ELISA and glutathione S-transferase, subtype alpha. Data at date of admission and at the date of peak levels of M65 were individually analyzed and correlated with the patients' prognosis and etiology. The predictive sensitivity of total serum M65 for lethal outcome was comparable to the Model for End-Stage Liver Disease (MELD) score at time of admission and at its peak value. In contrast, serum bilirubin levels had no prognostic value, neither at admission nor at later time points. In order to accurately predict the clinical prognosis of ALF patients, we tested a modified MELD score where CK18 M65 substituted bilirubin. This CK18/M65-based MELD score significantly better predicted the prognosis of ALF patients compared with the current MELD score or KCC. A combination of tested parameters contributed to improved discrimination of ALF etiologies by applying cell death and established laboratory parameters. The CK18 M65-based MELD score has superior sensitivity and specifically predicts survival of ALF patients. Further prospective clinical studies could validate its potential role to predict requirement of LTx in ALF patients.