Multi-level evidence that circulating CK18 is a biomarker of tumour burden in colorectal cancer

Pharmacodynamics of Cyclin D1 Degradation in Ovarian Cancer Xenografts with Repeated Oral SHetA2 Dosing

SHetA2 is a promising, orally active small molecule with anticancer properties that target heat shock proteins. In this study, we aimed to investigate the pharmacodynamic (PD) effects of SHetA2 using preclinical in vitro and in vivo models of ovarian cancer and establish a physiologically based pharmacokinetic (PBPK)/PD model to describe their relationships with SHetA2 concentrations in mice. We found that daily oral administration of 60 mg/kg SHetA2 for 7 days resulted in consistent plasma PK and tissue distribution, achieving tumor drug concentrations required for growth inhibition in ovarian cancer cell lines. SHetA2 effectively induced cyclin D1 degradation in cancer cells in a dose-dependent manner, with up to 70% reduction observed and an IC50 of 4~5 µM. We identified cyclin D1 as a potential PD marker for SHetA2, based on a well-correlated time profile with SHetA2 PK. Additionally, we examined circulating levels of ccK18 as a non-invasive PD marker for SHetA2-induced apoptotic activity and found it unsuitable due to high variability. Using a PBPK/PD model, we depicted SHetA2 levels and their promoting effects on cyclin D1 degradation in tumors following multiple oral doses. The model suggested that twice-daily dosing regimens would be effective for sustained reduction in cyclin D1 protein. Our study provides valuable insights into the PK/PD of SHetA2, facilitating future clinical trial designs and dosing schedules.

Hepatocyte-derived biomarkers predict liver-related events at 2 years in Child-Pugh class A alcohol-related cirrhosis

BACKGROUND & AIMS

In patients with compensated alcohol-related cirrhosis, reliable prognostic biomarkers are lacking. Keratin-18 and hepatocyte-derived large extracellular vesicle (lEV) concentrations reflect disease activity, but their ability to predict liver-related events is unknown.

METHODS

We measured plasma keratin-18 and hepatocyte lEV concentrations in 500 patients with Child-Pugh class A alcohol-related cirrhosis. The ability of these hepatocyte-derived biomarkers, alone or combined with model for end-stage liver disease (MELD) and FibroTest scores, to predict liver-related events at 2 years was analyzed, taking into account the alcohol consumption at inclusion and during follow-up.

RESULTS

Keratin-18 and hepatocyte lEV concentrations increased with alcohol consumption. In patients without active alcohol consumption at enrollment (n = 419), keratin-18 concentration predicted liver-related events at 2 years, independently of FibroTest and MELD. Patients with both keratin-18 concentrations >285 U/L and FibroTest >0.74 had a 24% cumulative incidence of liver-related events at 2 years, vs. 5% to 14% in other groups of patients. Similar results were obtained when combining keratin-18 concentrations >285 U/L with MELD >10. In patients with active alcohol consumption at enrollment (n = 81), hepatocyte lEVs predicted liver-related events at 2 years, independently of FibroTest and MELD. Patients with both hepatocyte lEV concentrations >50 U/L and FibroTest >0.74 had a 62% cumulative incidence of liver-related events at 2 years, vs. 8% to 13% in other groups of patients. Combining hepatocyte lEV concentrations >50 U/L with MELD >10 had a lower discriminative ability. Similar results were obtained when using decompensation of cirrhosis, defined according to Baveno VII criteria, as an endpoint.

CONCLUSION

In patients with Child-Pugh class A alcohol-related cirrhosis, combining hepatocyte-derived biomarkers with FibroTest or MELD scores identifies patients at high risk of liver-related events, and could be used for risk stratification and patient selection in clinical trials.

IMPACT AND IMPLICATIONS

In patients with compensated alcohol-related cirrhosis, reliable predictors of outcome are lacking. In patients with Child-Pugh class A alcohol-related cirrhosis, combining hepatocyte-derived biomarkers (keratin-18 and hepatocyte-large extracellular vesicles) with FibroTest or MELD scores identifies those at high risk of liver-related events at 2 years. The identified patients at high risk of liver-related events are the target-of-choice population for intensive surveillance (e.g., referral to tertiary care centers; intensive control of risk factors) and inclusion in clinical trials.

Circulating caspase-cleaved cytokeratin 18 correlates with tumour burden and response to therapy in patients with colorectal cancer liver metastasis

BACKGROUND AND AIMS

Systemic chemotherapy followed by hepatic resection is the treatment of choice for patients with colorectal cancer liver metastasis (CRCLM) but reliable biomarkers predicting response to therapy are needed. Spontaneous apoptosis of single tumour cells is common in CRCLM. We explored the potential of circulating apoptosis markers to predict treatment response.

MATERIALS AND METHODS

Fifty-eight patients with CRCLM or hepatocellular carcinoma (HCC) were included in this study. Tumour tissue and blood samples were obtained before and after initiation of chemotherapy. Immunohistochemistry and ELISA assays were utilized to quantify the apoptosis marker caspase-cleaved cytokeratin 18 (M30) in tissue and circulation.

RESULTS

CRCLM tissues showed more apoptotic tumour cells than HCC, or healthy liver. This was associated with elevated levels of circulating M30 (median = 244 U/l vs. 37 U/l in healthy controls, p = 0.009) which correlated with tumour volume (r² = 0.92). Patients with progressive disease during chemotherapy showed higher M30 levels before therapy than responders (745 U/l vs. 136 U/l, p = 0.016). The predictive potential of M30 was higher than that of the tumour markers CA19-9 or CEA (AUC: 0.93, 0.63, and 0.78, respectively).

CONCLUSIONS

Apoptotic tumour cells release cellular debris into the circulation, which provides information about tumour size and vitality.

Roles of Keratins in Intestine

Keratins make up a major portion of epithelial intermediate filament proteins. The widely diverse keratins are found in both the small and large intestines. The human intestine mainly expresses keratins 8, 18, 19, and 20. Many of the common roles of keratins are for the integrity and stability of the epithelial cells. The keratins also protect the cells and tissue from stress and are biomarkers for some diseases in the organs. Although an increasing number of studies have been performed regarding keratins, the roles of keratin in the intestine have not yet been fully understood. This review focuses on discussing the roles of keratins in the intestine. Diverse studies utilizing mouse models and samples from patients with intestinal diseases in the search for the association of keratin in intestinal diseases have been summarized.

Hsa-miR-186-3p suppresses colon cancer progression by inhibiting KRT18/MAPK signaling pathway

This study aimed to determine the effect of miR-186-3p and KRT18 interaction on the biological behavior of colon cancer cells. A biotin-microRNA pull-down assay was performed to identify potential miRNAs. qRT-PCR was used to verify the KRT18 and miR-186-3p levels. In addition, Western blotting was used to detect the KRT18 protein levels. The functional connection between KRT18 and miR-186-3p was confirmed using a dual luciferase reporter assay. BrdU incorporation, MTT assay, and flow cytometry were performed to verify the biological function coupled with in vivo assays. A significant decrease in miR-186-3p expression was observed in colon carcinoma tissues and cells. Functionally, overexpression of miR-186-3p displayed an obvious suppressive action on cell proliferation and viability, and a stimulatory action on the apoptotic ability of SW620 and SW480 cells. Conversely, reduced miR-186-3p had a marked stimulatory effect on proliferation and viability, and a suppressive apoptotic effect. Inhibition of tumorigenesis was observed in mice treated with the miR-186-3p agomir. Furthermore, we identified that miR-186-3p regulated KRT18 levels in colon carcinoma, where silenced KRT18 suppressed proliferation and viability and promoted apoptosis. However, the addition of a miR-186-3p inhibitor weakened the effects of si-KRT18. Additionally, the activation of MAPK signaling pathway upon miR-186-3p silencing was antagonized by the combined transfection of si-KRT18 and miR-186-3p inhibitor. miR-186-3p suppresses proliferation and viability, but facilitates apoptosis in colon cancer cells by targeting KRT18 and negatively regulating the MAPK signaling pathway, indicating that the miR-186-3p/KRT18 axis may be a promising therapeutic target for colon carcinoma.Abbreviations: KRT18: keratin 18; NC: negative control; si‑: small interfering RNA; inhibitor: miR-186-3p inhibitor; OD: optical density; PI: propidium iodide; FITC: fluorescein isothiocyanate; 3'UTR: 3'untranslated region; WT: wild-type; MUT: mutant-type; miR: microRNA.

Serum Cytokeratin 18 as a Metastatic and Therapeutic Marker for Extramammary Paget's Disease

Extramammary Paget's disease (EMPD) is a rare cutaneous adenocarcinoma with unfavorable prognosis once it becomes invasive. A tumor marker that reflects disease progression is required for adequate management of this disease. Cytokeratin 18 is highly expressed in many types of cancer and its soluble forms are detected by M30 (for caspase-cleaved form) and M65 (for both caspase-cleaved and intact forms) assays. Here, we report that tumor cells of EMPD in both lesional skin and lymph node metastasis are positive for CK18 immunohistochemically and the baseline serum M30 and M65 levels in metastatic EMPD patients are significantly higher than those in non-metastatic patients. In addition, serial serum M30 and M65 levels might reflect recurrence of EMPD and response to chemotherapy. These results suggest that serum CK18 levels may be a useful tumor marker for advanced EMPD.

Effect of oxaliplatin plus 5-fluorouracil or capecitabine on circulating and imaging biomarkers in patients with metastatic colorectal cancer: a prospective biomarker study

BACKGROUND

Patients with metastatic colorectal cancer are treated with cytotoxic chemotherapy supplemented by molecularly targeted therapies. There is a critical need to define biomarkers that can optimise the use of these therapies to maximise efficacy and avoid unnecessary toxicity. However, it is important to first define the changes in potential biomarkers following cytotoxic chemotherapy alone. This study reports the impact of standard cytotoxic chemotherapy across a range of circulating and imaging biomarkers.

METHODS

A single-centre, prospective, biomarker-driven study. Eligible patients included those diagnosed with colorectal cancer with liver metastases that were planned to receive first line oxaliplatin plus 5-fluorouracil or capecitabine. Patients underwent paired blood sampling and magnetic resonance imaging (MRI), and biomarkers were associated with progression-free survival (PFS) and overall survival (OS).

RESULTS

Twenty patients were recruited to the study. Data showed that chemotherapy significantly reduced the number of circulating tumour cells as well as the circulating concentrations of Ang1, Ang2, VEGF-A, VEGF-C and VEGF-D from pre-treatment to cycle 2 day 2. The changes in circulating concentrations were not associated with PFS or OS. On average, the MRI perfusion/permeability parameter, Ktrans, increased in response to cytotoxic chemotherapy from pre-treatment to cycle 2 day 2 and this increase was associated with worse OS (HR 1.099, 95%CI 1.01-1.20, p = 0.025).

CONCLUSIONS

In patients diagnosed with colorectal cancer with liver metastases, treatment with standard chemotherapy changes cell- and protein-based biomarkers, although these changes are not associated with survival outcomes. In contrast, the imaging biomarker, Ktrans, offers promise to direct molecularly targeted therapies such as anti-angiogenic agents.

Signs of carcinogenicity induced by parathion, malathion, and estrogen in human breast epithelial cells (Review)

Cancer development is a multistep process that may be induced by a variety of compounds. Environmental substances, such as pesticides, have been associated with different human diseases. Organophosphorus pesticides (OPs) are among the most commonly used insecticides. Despite the fact that organophosphorus has been associated with an increased risk of cancer, particularly hormone-mediated cancer, few prospective studies have examined the use of individual insecticides. Reported results have demonstrated that OPs and estrogen induce a cascade of events indicative of the transformation of human breast epithelial cells. In vitro studies analyzing an immortalized non-tumorigenic human breast epithelial cell line may provide us with an approach to analyzing cell transformation under the effects of OPs in the presence of estrogen. The results suggested hormone-mediated effects of these insecticides on the risk of cancer among women. It can be concluded that, through experimental models, the initiation of cancer can be studied by analyzing the steps that transform normal breast cells to malignant ones through certain substances, such as pesticides and estrogen. Such substances cause genomic instability, and therefore tumor formation in the animal, and signs of carcinogenesis in vitro. Cancer initiation has been associated with an increase in genomic instability, indicated by the inactivation of tumor-suppressor genes and activation of oncogenes in the presence of malathion, parathion, and estrogen. In the present study, a comprehensive summary of the impact of OPs in human and rat breast cancer, specifically their effects on the cell cycle, signaling pathways linked to epidermal growth factor, drug metabolism, and genomic instability in an MCF-10F estrogen receptor-negative breast cell line is provided.

Plasma Cytokeratin 18 and fecal Alpha-1 Antitrypsin concentrations in dogs with osteosarcoma receiving carboplatin chemotherapy

Gastrointestinal (GI) toxicosis is a common side effect of cytotoxic chemotherapy treatment in humans and dogs. Measurement of cytokeratin 18 (CK18), an intracellular structural protein released during epithelial apoptosis, and Alpha1‐Antitrypsin (A1AT) in faeces provides a mechanism for evaluating damage to the intestinal mucosa secondary to cytotoxic chemotherapy. Our goal was to evaluate the clinical utility of plasma CK18 and faecal A1‐AT levels as non‐invasive biomarkers of cytotoxic chemotherapy induced GI toxicity. We conducted a prospective cohort study in dogs (N = 10) with osteosarcoma undergoing amputation followed by carboplatin chemotherapy. We hypothesized that plasma CK18 and faecal A1‐AT levels would increase following carboplatin administration due to drug‐induced GI epithelial damage/apoptosis, and that plasma CK18 and faecal A1‐AT levels would correlate with severity of GI toxicity. Mean baseline plasma CK18 concentration was variable amongst patients; however, CK18 concentration prior to carboplatin chemotherapy treatment was not significantly different from CK18 levels after treatment. There was significant intra and inter‐patient variability in mean faecal A1‐AT levels at baseline. Mean A1‐AT concentration did not change significantly from day 0 to day 21. Gastrointestinal toxicity was minimal; therefore, we were unable to determine the association of plasma CK18 and faecal A1‐AT concentrations with development of GI toxicosis. In this study population, plasma CK18 and faecal A1‐AT concentration were not clinically useful biomarkers for the detection of GI toxicosis secondary to carboplatin administration. Further prospective evaluation of CK18 and A1‐AT as biomarkers of drug‐induced GI toxicity is warranted in a larger cohort of dogs receiving cytotoxic chemotherapy.

AVMA clinical trial registration number: AAHSD004827.

Keratin intermediate filaments in the colon: guardians of epithelial homeostasis

Keratin intermediate filament proteins are major cytoskeletal components of the mammalian simple layered columnar epithelium in the gastrointestinal tract. Human colon crypt epithelial cells express keratins 18, 19 and 20 as the major type I keratins, and keratin 8 as the type II keratin. Keratin expression patterns vary between species, and mouse colonocytes express keratin 7 as a second type II keratin. Colonic keratin patterns change during cell differentiation, such that K20 increases in the more differentiated crypt cells closer to the central lumen. Keratins provide a structural and mechanical scaffold to support cellular stability, integrity and stress protection in this rapidly regenerating tissue. They participate in central colonocyte processes including barrier function, ion transport, differentiation, proliferation and inflammatory signaling. The cell-specific keratin compositions in different epithelial tissues has allowed for the utilization of keratin-based diagnostic methods. Since the keratin expression pattern in tumors often resembles that in the primary tissue, it can be used to recognize metastases of colonic origin. This review focuses on recent findings on the biological functions of mammalian colon epithelial keratins obtained from pivotal in vivo models. We also discuss the diagnostic value of keratins in chronic colonic disease and known keratin alterations in colon pathologies. This review describes the biochemical properties of keratins and their molecular actions in colonic epithelial cells and highlights diagnostic data in colorectal cancer and inflammatory bowel disease patients, which may facilitate the recognition of disease subtypes and the establishment of personal therapies in the future.

Systemic inflammation is associated with circulating cell death released keratin 18 fragments in colorectal cancer

Systemic inflammation is a stage-independent marker of poor prognosis in colorectal cancer (CRC), activated in a complex, multifactorial process. It has been proposed that one of the main factors driving systemic inflammation may be tumor necrosis. Keratin 18 (KRT18) fragments are released from dead cells and their serum levels are markers for apoptotic and necrotic cell death. In CRC, high KRT18 levels associate with advanced disease, but their relationship with tumor necrosis and systemic inflammation is unknown. In this study, serum total soluble KRT18 (tKRT18) and apoptosis-related, caspase-cleaved fragment (aKRT18) levels were measured preoperatively from 328 CRC patients, and their difference was calculated to assess necrosis related KRT18 (nKRT18) levels. The relationships of these markers with tumor necrosis, clinicopathologic features, systemic inflammation markers (C-reactive protein, albumin, and 13 cytokines), and survival were analyzed. High serum tKRT18, aKRT18, and nKRT18 levels showed association with a higher extent of tumor necrosis, distant metastasis, and increased levels of several markers of systemic inflammation, including CXCL8. High serum tKRT18 (multivariable HR 1.94, 95% CI 1.28-2.95, p = .002) and nKRT18 (multivariable HR 1.87, 95% CI 1.24-2.82, p = .003) levels were associated with poor overall survival independent of potential confounding factors. Our results show that tumor necrosis in CRC contributes to serum levels of KRT18 fragments, and both necrosis and KRT18 levels associate with systemic inflammation. Moreover, we show that serum tKRT18 and nKRT18 levels have independent prognostic value in CRC. Our observations confirm the link between cell death and systemic inflammation.

Phosphorylation of keratin 18 serine 52 regulates mother-daughter centriole engagement and microtubule nucleation by cell cycle-dependent accumulation at the centriole

Serine-52 (Ser52) is the major physiologic site of keratin 18 (K18) phosphorylation. Here, we report that serine-52 phosphorylated K18 (phospho-Ser52 K18) accumulated on centrosomes in a cell cycle-dependent manner. Moreover, we found that phospho-Ser52 K18 was located at the proximal end of the mother centriole. Transfection with the K18 Ser52 → Ala (K18 S52A) mutant prevented centriole localization of phospho-Ser52 K18 and resulted in separation of the mother-daughter centrioles. Inhibition of microtubule polymerization led to the disappearance of aggregated phospho-Ser52 K18 on the centrosome; removal of inhibitors resulted in reaccumulation of phospho-Ser52 K18 in microtubule-organizing centers. Transfection with a K18 S52A mutant inhibited microtubule nucleation. These results reveal a cell cycle-dependent change in centrosome localization of phospho-Ser52 k18 and strongly suggest that the phosphorylation status of Ser52 K18 of mother centrioles plays a critical role in maintaining a tight engagement between mother and daughter centrioles and also contributes to microtubule nucleation.

Circulating biomarkers of cell death

Numerous disease states are associated with cell death. For many decades, apoptosis and accidental necrosis have been assumed to be the two ways how a cell can die. The recent discovery of additional cell death processes such as necroptosis, ferroptosis or pyroptosis revealed a complex interplay between cell death mechanisms and diseases. Depending on the particular cell death pathway, cells secrete distinct molecular patterns, which differ between cell death types. This review focusses on released molecules, detectable in the blood flow, and their potential role as circulating biomarkers of cell death. We elucidate the molecular background of different biomarkers and give an overview on their correlation with disease stage, therapy response and prognosis in patients.

Prognostic value of non-invasive serum Cytokeratin 18 detection in gastrointestinal cancer: a meta-analysis

Background: Gastrointestinal cancer is one of the most common neoplasms. Cytokeratin 18(CK18) is widely expressed in many different organs and cancers. Emerging data suggested conflicting results about the role of CK18 during carcinogenesis. The aim of this study is to systematically review the prognostic value of circulating CK18 (M65) and caspase-Cleaved CK18 (M30) in digestive cancers.

Materials and Methods: We searched major database for manuscripts reporting the effect of pretreatment CK18 on survival of digestive cancer patients. Revman5.3 and R were the software used for analysis. Pooled multivariable-adjusted hazard ratios (HR) for overall survival (OS) were calculated in all patients and many different subgroup analyses by stratifying on tumor type, metastasis stage, and ethnicity.

Results: 11 original studies were included for analysis. A low level of M30 and M65 were shown to be a protective factor for all cancer patients (HR 0.49, 95%CI 0.33-0.73, P=0.0003; HR 0.48, 95% CI 0.32-0.70, P =0.0001, respectively). The low M30 remained to be a protective factor for metastasized cancer patients while M65 had no statistically significant correlation with prognosis.

Conclusions: Non-invasive total and cleaved CK18 level detection by ELISA could be potentially a useful predictor of prognosis of digestive cancer patients. Further studies are warranted to investigate the molecular mechanisms of CK18.

Cytokeratin 18 regulates the transcription and alternative splicing of apoptotic‑related genes and pathways in HeLa cells

Cytokeratin 18 (CK18), one of the major components of intermediate filaments (IF) in simple epithelial cells, undergoes caspase-mediated cleavage upon epithelial cell necrosis and apoptosis. CK18 has been used as a biomarker of several cancers and has been reported to be dysregulated in cervical cancers. The effects of dysregulated expression of CK18 at a molecular level are, however, unclear. In the present study, the function of CK18 in HeLa cells, a cell line derived from a cervical cancer cells, was investigated using shRNA knockdown. Reduced levels of CK18 led to a significant decrease in cell apoptosis, compared with control cells. Notably, RNA-seq analysis of the transcriptomes of HeLa cells, with or without CK18 knockdown, revealed that genes in the NF-κB pathway, and certain apoptosis pathways, were under global transcriptional and alternative splicing regulation. Quantitative RT-PCR confirmed the CK18-regulated transcription of apoptotic genes FAS and FADD, as well as immune genes CXCL2 and CD79B, in addition to alternative splicing of FAS and CTNNB1. Western blot analysis further revealed that CK18 knockdown led to reduced expression of CASP8. In conclusion, the present study indicated that CK18 played a role in apoptosis, which may be mediated via a feed-back regulation loop and may involve regulation of transcription and alternative splicing of a number of genes in apoptotic pathways.

Plasma Tie2 is a tumor vascular response biomarker for VEGF inhibitors in metastatic colorectal cancer

Oncological use of anti-angiogenic VEGF inhibitors has been limited by the lack of informative biomarkers. Previously we reported circulating Tie2 as a vascular response biomarker for bevacizumab-treated ovarian cancer patients. Using advanced MRI and circulating biomarkers we have extended these findings in metastatic colorectal cancer (n = 70). Bevacizumab (10 mg/kg) was administered to elicit a biomarker response, followed by FOLFOX6-bevacizumab until disease progression. Bevacizumab induced a correlation between Tie2 and the tumor vascular imaging biomarker, Ktrans (R:-0.21 to 0.47) implying that Tie2 originated from the tumor vasculature. Tie2 trajectories were independently associated with pre-treatment tumor vascular characteristics, tumor response, progression free survival (HR for progression = 3.01, p = 0.00014; median PFS 248 vs. 348 days p = 0.0008) and the modeling of progressive disease (p < 0.0001), suggesting that Tie2 should be monitored clinically to optimize VEGF inhibitor use. A vascular response is defined as a 30% reduction in Tie2; vascular progression as a 40% increase in Tie2 above the nadir. Tie2 is the first, validated, tumor vascular response biomarker for VEGFi.

The use of circulating biomarkers in early clinical trials in patients with cancer

The development of targeted therapies has changed the approach to early oncological clinical trial design. Identification of patient populations most likely to derive benefit and the biologically effective dose are now as important as determination of the maximum tolerated dose. Completion of the 'pharmacological audit trail' highlights drugs most likely to progress through to license, so resources can be allocated appropriately. Key to the success of this changing model is the validation/qualification of circulating biomarkers. These might provide a readily accessible and dynamic picture of drug effect, tumor response and toxicity with minimum risk to patients. This review article examines circulating biomarkers currently used in early oncological clinical trials. It considers the evidence for their employment, limitations and challenges for future development.

Cediranib or placebo in combination with cisplatin and gemcitabine chemotherapy for patients with advanced biliary tract cancer (ABC-03): a randomised phase 2 trial

BACKGROUND

Cisplatin and gemcitabine is the standard first-line chemotherapy regimen for patients with advanced biliary tract cancer; expression of VEGF and its receptors is associated with adverse outcomes. We aimed to assess the effect of the addition of cediranib (an oral inhibitor of VEGF receptor 1, 2, and 3) to cisplatin and gemcitabine on progression-free survival.

METHODS

In this multicentre, placebo-controlled, randomised phase 2 study, we recruited patients aged 18 years or older with histologically confirmed or cytologically confirmed advanced biliary tract cancer from hepatobiliary oncology referral centres in the UK. Patients were eligible if they had an ECOG performance status of 0-1 and an estimated life expectancy of longer than 3 months. Patients were given first-line cisplatin and gemcitabine chemotherapy (25 mg/m(2) cisplatin and 1000 mg/m(2) gemcitabine [on days 1 and 8 every 21 days, for up to eight cycles]) with either 20 mg oral cediranib or placebo once a day until disease progression. We randomly assigned patients (1:1) with a minimisation algorithm, incorporating the stratification factors: extent of disease, primary disease site, previous treatment, ECOG performance status, and centre. The primary endpoint was progression-free survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00939848, and was closed on Sept 30, 2014; results of the final analysis for the primary endpoint are presented.

FINDINGS

Between April 5, 2011, and Sept 28, 2012, we enrolled 124 patients (62 in each group). With a median follow-up of 12·2 months (IQR 7·3-18·5), median progression-free survival was 8·0 months (95% CI 6·5-9·3) in the cediranib group and 7·4 months (5·7-8·5) in the placebo group (HR 0·93, 80% CI 0·74-1·19, 95% CI 0·65-1·35; p=0·72). Patients who received cediranib had more grade 3-4 toxic effects than did patients who received placebo: hypertension (23 [37%] vs 13 [21%]; p=0·05), diarrhoea (eight [13%] vs two [3%]; p=0·05); platelet count decreased (ten [16%] vs four [6%]; p=0·09), white blood cell decreased (15 [24%] vs seven [11%]; p=0·06) and fatigue (16 [24%] vs seven [11%]; p=0·04).

INTERPRETATION

Cediranib did not improve the progression-free survival of patients with advanced biliary tract cancer in combination with cisplatin and gemcitabine, which remains the standard of care. Although patients in the cediranib group had more adverse events, we recorded no unexpected toxic effects. The role of VEGF inhibition in addition to chemotherapy for patients with advanced biliary tract cancer remains investigational.

FUNDING

Cancer Research UK and AstraZeneca Pharmaceuticals.

(Cleaved) CK18 serum and tissue expression levels differentiate acute HCV reinfection from acute rejection in liver allografts

BACKGROUND & AIMS

Orthotopic liver transplantation (OLT) is the sole therapeutic option to cure end-stage liver diseases including HCV-related cirrhosis. Timely and precise differentiation of relevant acute HCV reinfection from acute rejection after OLT is vital for appropriate therapy. Aim of this study was to evaluate the usefulness of (non-) invasive apoptosis (M30) and necrosis (M65) determination in the differential diagnosis of acute (and chronic) HCV reinfection vs. acute rejection in liver allografts.

METHODS

Serum samples and liver biopsy tissues were available from 76 patients including a control group (19× NAFL, 19× NASH, 16× acute rejection, 11× acute and 11× chronic HCV reinfection) and were analysed using M30- and M65 ELISAs (M30S, M65S) and M30-immunohistochemistry (M30H). Clinical and serological data were collected.

RESULTS

M30S, M65S and M30H were highly correlated with diagnostic groups in the total cohort (all P < 0.0001). M30S, M65S and M30H were independently able to differentiate acute HCV reinfection from acute rejection (P = 0.048, P = 0.001, P = 0.010) with moderate to excellent diagnostic accuracy (sensitivity, specificity, cut-off-value in M30S: 70%, 75%, 1025 U/L; M65S: 100%, 92%, 1308 U/L; M30H: 73%, 88%, 0.3%).

CONCLUSIONS

M30-, M65-ELISAs and M30-immunohistochemistry are potential useful tools in differentiating acute HCV reinfection from acute rejection facilitating both speed and accuracy of the diagnostic process for the clinician and hepatopathologist. In this context, M65S provided superior diagnostic characteristics compared to M30-based methods. However, being the first analysis of (cleaved) CK18 serum and tissue expression levels in this context, the results need to be verified in further studies.

Percentage Change in Plasma Cytokeratin 18 Is Associated with Clinical Outcomes in Patients Receiving Pemetrexed and Carboplatin for the Adenocarcinoma Subtype of NSCLC

BACKGROUND

The adenocarcinoma subtype of non-small cell lung cancer (adeno-NSCLC) is routinely treated with chemotherapy if patients do not have molecular aberrations such as epidermal growth factor receptor mutations or anaplastic lymphoma kinase rearrangements. There are currently no validated biomarkers that can predict if patients will gain clinical benefit from chemotherapy, leading to a majority of patients receiving many cycles of unnecessary chemotherapy. We hypothesized that the percentage rise in plasma caspase-cleaved cytokeratin 18 (cCK18) and total cytokeratin 18 (tCK18) assessed before and after chemotherapy correlates with the radiological response to chemotherapy.

METHODS

Plasma samples from 40 patients with stage IV adeno-NSCLC, treated with first-line chemotherapy with carboplatin (AUC5) plus pemetrexed (500 mg/m(2)), were collected prior to chemotherapy and 48 h after treatment. ELISA was used to quantify cCK18 and tCK18.

RESULTS

The male-to-female ratio was 3:1, and the median age of patients was 63 years. Patients who had a clinical benefit (complete response, partial response or stable disease) at the first radiological assessment following chemotherapy had a significantly higher percentage change in plasma tCK18 levels compared to those who had no clinical benefit, i.e. progressive disease (69.5 ± 75.1 vs. 25.3 ± 30.9%, respectively; p = 0.042). The receiver operating characteristic area was 0.712 (p = 0.039). There was an increase in the percentage change in cCK18 in patients with clinical benefit compared to those without clinical benefit but this was not statistically significant (57.6 ± 112.8 vs. 24.38 ± 45.1%, respectively; p = 0.85).

CONCLUSIONS

The percentage change in plasma tCK18 levels before and after the first cycle of pemetrexed and carboplatin chemotherapy is associated with clinical benefit. If validated in larger cohorts, this test can be used to identify patients unlikely to respond to treatment who can thus be offered alternative treatments or entry into clinical trials.

Keratins in health and disease

The cytoprotective keratins (K) compose the intermediate filaments of epithelial cells and their inherited and spontaneous mutations give rise to keratinopathies. For example, mutations in K1/K5/K10/K14 cause epidermal skin diseases whereas simple epithelial K8/K18/K19 variants predispose to development of several liver disorders. Due to their abundance, tissue- and context-specific expression, keratins constitute excellent diagnostic markers of both neoplastic and non-neoplastic diseases. During injury and in disease, keratin expression levels, cellular localization or posttranslational modifications are altered. Accumulating evidence suggests that these changes modulate multiple processes including cell migration, tumor growth/metastasis and development of infections. Therefore, our understanding of keratins is shifting from diagnostic markers to active disease modifiers.

Serological markers of enterocyte damage and apoptosis in patients with celiac disease, autoimmune diabetes mellitus and diabetes mellitus type 2

Impairment of mucosal barrier integrity of small intestine might be causative in immune-mediated gastrointestinal diseases. We tested the markers of epithelial apoptosis - cytokeratin 18 caspase-cleaved fragment (cCK-18), and enterocyte damage - intestinal fatty acid-binding protein (I-FABP) and soluble CD14 (sCD14) in sera of patients with untreated celiac disease (CLD), those on gluten-free diet (CLD-GFD), patients with autoimmune diabetes mellitus (T1D), T1D with insulitis (T1D/INS), and diabetes mellitus type 2 (T2D). We found elevated levels of cCK-18 (P<0.001), I-FABP (P<0.01) and sCD14 (P<0.05) in CLD when compared to healthy controls. However, the levels of cCK-18 (P<0.01) and I-FABP (P<0.01) in CLD-GFD were higher when compared with controls. Interestingly, elevated levels of cCK-18 and I-FABP were found in T2D and T1D (P<0.001), and T1D/INS (P<0.01, P<0.001). Twenty-two out of 43 CLD patients were seropositive for cCK-18, 19/43 for I-FABP and 11/43 for sCD14; 9/30 of T2D patients were positive for cCK-18 and 5/20 of T1D/INS for sCD14, while in controls only 3/41 were positive for cCK-18, 3/41 for I-FABP and 1/41 for sCD14. We documented for the first time seropositivity for sCD14 in CLD and potential usefulness of serum cCK-18 and I-FABP as markers of gut damage in CLD, CLD-GFD, and diabetes.

Diagnostic value of serum M30 and M65 in patients with nasopharyngeal carcinoma

M30 and M65 are circulating fragments of cytokeratin 18 released during apoptotic cell death and regarded as markers of cell death in patients with various tumor types. Our aim was to investigate the clinical and prognostic significance of the serum M30 and M65 concentrations in patients with advanced nasopharyngeal carcinoma. Thirty-two patients with nasopharyngeal cancer and 32 control subjects were investigated. Serum samples were obtained on first admission before any treatment was initiated. Serum M30 and M65 concentrations were measured by quantitative enzyme-linked immunosorbent assay. Median serum M30 (181.5 vs. 45.5 U/L, p < 0.001) and M65 (384.2 vs. 179.1 U/L, p < 0.001) concentrations were significantly higher in patients with advanced nasopharyngeal carcinomas than in controls. receiver operating characteristic (ROC) analysis showed that a cutoff for M30 of 225 U/L had a sensitivity of 62.5% and a specificity of 73.9% (area under the curve (AUC) = 0.592, 95% confidence interval (CI) 35.3-83.2, p = 0.44), while a cutoff for M65 of 423.4 U/L had a sensitivity of 75.1% and a specificity of 65.6% (AUC = 0.562, 95 % CI 36.0-76.5, p = 0.60). However, serum M30 and M65 were not important prognostic factors for progression-free survival. There were no statistically significant correlations between serum M30 and M65 concentrations and clinicodemographical variables. Serum M30 and M65 concentrations were found to have a diagnostic value in nasopharyngeal cancer. However, neither M30 nor M65 serum levels played a prognostic role in the outcome in nasopharyngeal cancer patients.

Circulating biomarkers in hepatocellular carcinoma

PURPOSE

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Carbamoyl phosphate synthetase-1 is a rapid turnover biomarker in mouse and human acute liver injury

Several serum markers are used to assess hepatocyte damage, but they have limitations related to etiology specificity and prognostication. Identification of novel hepatocyte-specific biomarkers could provide important prognostic information and better pathogenesis classification. We tested the hypothesis that hepatocyte-selective biomarkers are released after subjecting isolated mouse hepatocytes to Fas-ligand-mediated apoptosis. Proteomic analysis of hepatocyte culture medium identified the mitochondrial matrix protein carbamoyl phosphate synthetase-1 (CPS1) among the most readily detected proteins that are released by apoptotic hepatocytes. CPS1 was also detected in mouse serum upon acute challenge with Fas-ligand or acetaminophen and in hepatocytes upon hypoosmotic stress, independent of hepatocyte caspase activation. Furthermore, CPS1 was observed in sera of mice chronically fed the hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Mouse CPS1 detectability was similar in serum and plasma, and its half-life was 126 ± 9 min. Immune staining showed that CPS1 localized to mouse hepatocytes but not ductal cells. Analysis of a few serum samples from patients with acute liver failure (ALF) due to acetaminophen, Wilson disease, or ischemia showed readily detectable CPS1 that was not observed in several patients with chronic viral hepatitis or in control donors. Notably, CPS1 rapidly decreased to undetectable levels in sera of patients with acetaminophen-related ALF who ultimately recovered, while alanine aminotransferase levels remained elevated. Therefore, CPS1 becomes readily detectable upon hepatocyte apoptotic and necrotic death in culture or in vivo. Its abundance and short serum half-life, compared with alanine aminotransferase, suggest that it may be a useful prognostic biomarker in human and mouse liver injury.

Analysis of key genes and pathways associated with colorectal cancer with microarray technology

OBJECTIVE

Microarray data were analyzed to explore key genes and their functions in progression of colorectal cancer (CRC).

METHODS

Two microarray data sets were downloaded from Gene Expression Omnibus (GEO) database and differentially expressed genes (DEGs) were identified using corresponding packages of R. Functional enrichment analysis was performed with DAVID tools to uncover their biological functions.

RESULTS

631 and 590 DEGs were obtained from the two data sets, respectively. A total of 32 common DEGs were then screened out with the rank product method. The significantly enriched GO terms included inflammatory response, response to wounding and response to drugs. Two interleukin-related domains were revealed in the domain analysis. KEGG pathway enrichment analysis showed that the PPAR signaling pathway and the renin-angiotensin system were enriched in the DEGs.

CONCLUSIONS

Our study to systemically characterize gene expression changes in CRC with microarray technology revealed changes in a range of key genes, pathways and function modules. Their utility in diagnosis and treatment now require exploration.

Diagnostic and prognostic significance of cell death and macrophage activation markers in patients with hepatocellular carcinoma

BACKGROUND & AIMS

The serum cell death parameters M30 and M65 and the macrophage activation marker sCD163 (soluble CD163) are elevated in patients with acute and chronic liver diseases. However, their diagnostic and prognostic potential in patients with hepatocellular carcinoma (HCC) has not yet been investigated.

METHODS

Serum levels of M30, M65, and sCD163 were measured in two cohorts of HCC patients and a cohort of cirrhotic patients. The parameters were compared between patients with and without HCC and the overall survival (OS) times according to M30, M65, and sCD163 were assessed.

RESULTS

M30 and M65 levels were higher in HCC patients than in cirrhotic patients (both p < 0.001). M65 was an independent parameter for non-invasive identification of HCC patients by logistic regression analysis and could supplement AFP (alpha-fetoprotein) and abdominal ultrasound in non-invasive detection of HCC patients. High M65 serum levels as well as high sCD163 concentrations were associated with an impaired prognosis in univariate Cox regression analysis. The sCD163 level was associated with OS independently of the CLIP (Cancer of the Liver Italian Program) score, the BCLC (Barcelona Clinic Liver Cancer) stage, and the CRP (C-reactive protein) level in a multivariate Cox regression model.

CONCLUSIONS

Serum M65 has the potential as a new diagnostic parameter for HCC and serum sCD163 is a new prognostic parameter in HCC patients.

The interaction between prognostic and pharmacodynamic biomarkers

Background:

Interactions between prognostic and pharmacodynamic (PD) biomarkers have received little attention.

Methods:

Prognostic and PD utilities were assessed with linear mixed-effects models using published data on repeated measurements of circulating caspase-cleaved (ctCK18) and total (tCK18) cytokeratin 18, in 57 patients with metastatic colorectal cancer undergoing chemotherapy.

Results:

The model for tCK18 (but not cCK18) separated the prognostic/PD interaction from the pure prognostic effect, illustrating the principle of dual prognostic and PD characteristics for a given biomarker.

Conclusion:

These models provide the framework for the analysis and interpretation of longitudinal data to detect prognostic/PD biomarker interactions.