Individualized metabolic profiling stratifies pancreatic and biliary tract cancer: a useful tool for innovative screening programs and predictive strategies in healthcare

Molecular Biomarkers in Cholangiocarcinoma: Focus on Bile

Hepatobiliary system cancers have demonstrated an increasing incidence rate in the past years. Without the presence of early symptoms, the majority of such cancers manifest with a set of similar symptoms, such as cholestasis resulting in posthepatic icterus. Differential diagnosis of hepatobiliary cancers is required for the therapy selection, however, the similarity of the symptoms complicates diagnostics. Thus, the search for molecular markers is of high interest for such patients. Cholangiocarcinoma (CCA) is characterized by a poor prognosis due to a low resectability rate, which occurs because this disease is frequently beyond the limits of surgical therapy at the time of diagnosis. The CCA is diagnosed by the combination of clinical/biochemical features, radiological methods, and non-specific serum tumor biomarkers, although invasive examination is still needed. The main disadvantage is limited specificity and sensitivity, which complicates early diagnostics. Therefore, prognostic and predictive biomarkers are still lacking and urgently needed for early diagnosis. In contrast to serum, bile is more accessible to identify biliary disease due to its simpler composition. Moreover, bile can contain higher concentrations of tumor biomarkers due to its direct contact with the tumor. It is known that the composition of the main bile component - bile acids, may vary during different diseases of the biliary tract. This review summarizes the recent developments in the current research on the diagnostic biomarkers for CCA in serum and bile and provides an overview of the methods of bile acids analysis.

Experimental Assessment of Leptomeningeal Metastasis Diagnosis in Medulloblastoma Using Cerebrospinal Fluid Metabolomic Profiles

Diagnosing leptomeningeal metastasis (LM) in medulloblastoma is currently based on positive cerebrospinal fluid (CSF) cytology or magnetic resonance imaging (MRI) finding. However, the relevance of discordant results has not been established. We evaluated the diagnostic potential of CSF metabolomic profiles in the medulloblastoma LM assessment. A total of 83 CSF samples from medulloblastoma patients with documented MRI and CSF cytology results at the time of sampling for LM underwent low-mass ions (LMIs) analysis using liquid chromatography-mass spectrometry. Discriminating LMIs were selected by a summed sensitivity and specificity (>160%) and LMI discriminant equation (LOME) algorithms, evaluated by measuring diagnostic accuracy for verifying LM groups of different MRI/cytology results. Diagnostic accuracy of LM in medulloblastoma was 0.722 for cytology and 0.889 for MRI. Among 6572 LMIs identified in all sample, we identified 27 discriminative LMIs differentiating MRI (+)/cytology (+) from MRI (-)/cytology (-). Using LMI discriminant equation (LOME) analysis, we selected 9 LMIs with a sensitivity of 100% and a specificity of 93.6% for differentiating MRI (+)/cytology (+) from MRI (-)/cytology (-). Another LOME of 20 LMIs significantly differentiated sampling time relative to treatment (p = 0.007) and the presence or absence of LM-related symptoms (p = 0.03) in the MRI (+)/cytology (-) group. CSF metabolomics of medulloblastoma patients revealed significantly different profiles among LM diagnosed with different test results. We suggest that LM patients could be screened by appropriately selected LOME-generated LMIs to support LM diagnosis by either MRI or cytology alone.

Health screening program revealed risk factors associated with development and progression of papillomacular bundle defect

BACKGROUND/AIMS

The papillomacular bundle (PMB) area is an important anatomical site associated with central vision. As preventive medicine and health screening examinations are now becoming commonplace, the incidental detection of papillomacular bundle defect (PMBD) on fundus photography has been increasing. However, clinical significance of incidental PMBD has not been well documented to date. Thus, through long-term and longitudinal observation, we aimed to investigate the risk factors for the development and progression of PMBD and its predictive role associated with systemic diseases and glaucoma.

METHODS

This longitudinal study included subjects who had undergone standardized health screening. We retrospectively reviewed patients for whom PMBD had been detected in fundus photography and followed up for more than 5 years. For a comparative analysis, non-PMBD groups of age- and gender-matched healthy controls were selected.

RESULTS

A total of about 67,000 fundus photographs were analyzed for 8.0 years, and 587 PMBD eyes were found. Among them, 234 eyes of 234 patients who had had fundus photographs taken for more than 5 years were finally included. A total of 216 eyes (92.3%) did not progress during the 8.1 ± 2.7 years, whereas 18 eyes (7.7%) showed progression at 7.6 ± 2.9 years after initial detection. A multivariate logistic regression analysis using 224 non-PMBD healthy controls revealed low body mass index (BMI < 20 kg/m2), systemic hypertension, and sclerotic changes of retinal artery as the significant risk factors for the development of PMBD. Regarding PMBD progression, low BMI, concomitant retinal nerve fiber layer defect (RNFLD) at non-PMB sites, optic disc hemorrhage, and higher vertical cup/disc ratio were individual significant risk factors.

CONCLUSION

PMBD is associated with ischemic effects. Although the majority of PMBD do not progress, some of cases are associated with glaucomatous damage in a long-term way. PMBD might be a personalized indicator representing ischemia-associated diseases and a predictive factor for diagnosis and preventive management of glaucoma.

An Updated Review of Pro- and Anti-Inflammatory Properties of Plasma Lysophosphatidylcholines in the Vascular System

Lysophosphatidylcholines are a group of bioactive lipids heavily investigated in the context of inflammation and atherosclerosis development. While present in plasma during physiological conditions, their concentration can drastically increase in certain inflammatory states. Lysophosphatidylcholines are widely regarded as potent pro-inflammatory and deleterious mediators, but an increasing number of more recent studies show multiple beneficial properties under various pathological conditions. Many of the discrepancies in the published studies are due to the investigation of different species or mixtures of lysophatidylcholines and the use of supra-physiological concentrations in the absence of serum or other carrier proteins. Furthermore, interpretation of the results is complicated by the rapid metabolism of lysophosphatidylcholine (LPC) in cells and tissues to pro-inflammatory lysophosphatidic acid. Interestingly, most of the recent studies, in contrast to older studies, found lower LPC plasma levels associated with unfavorable disease outcomes. Being the most abundant lysophospholipid in plasma, it is of utmost importance to understand its physiological functions and shed light on the discordant literature connected to its research. LPCs should be recognized as important homeostatic mediators involved in all stages of vascular inflammation. In this review, we want to point out potential pro- and anti-inflammatory activities of lysophospholipids in the vascular system and highlight recent discoveries about the effect of lysophosphatidylcholines on immune cells at the endothelial vascular interface. We will also look at their potential clinical application as biomarkers.

Discovery of Pancreatic Adenocarcinoma Biomarkers by Untargeted Metabolomics

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal cancers, with a 5-year survival rate of less than 5%. In fact, complete surgical resection remains the only curative treatment. However, fewer than 20% of patients are candidates for surgery at the time of presentation. Hence, there is a critical need to identify diagnostic biomarkers with potential clinical utility in this pathology. In this context, metabolomics could be a powerful tool to search for new robust biomarkers. Comparative metabolomic profiling was performed in serum samples from 59 unresectable PDAC patients and 60 healthy controls. Samples were analyzed by using an untargeted metabolomics workflow based on liquid chromatography, coupled to high-resolution mass spectrometry in positive and negative electrospray ionization modes. Univariate and multivariate analysis allowed the identification of potential candidates that were significantly altered in PDAC patients. A panel of nine candidates yielded excellent diagnostic capacities. Pathway analysis revealed four altered pathways in our patients. This study shows the potential of liquid chromatography coupled to high-resolution mass spectrometry as a diagnostic tool for PDAC. Furthermore, it identified novel robust biomarkers with excellent diagnostic capacities.

Mass spectrometry based proteomics and metabolomics in personalized oncology

Precision medicine (PM) means the customization of healthcare with decisions and practices adjusted to the individual patient. It includes personalized diagnostics, patients' sub-classification, individual treatment selection and the monitoring of its effectiveness. Currently, in oncology, PM is based on the molecular and cellular features of a tumor, its microenvironment and the patient's genetics and lifestyle. Surprisingly, the available targeted therapies were found effective only in a subset of patients. An in-depth understanding of tumor biology is crucial to improve their effectiveness and develop new therapeutic targets. Completion of genetic information with proteomics and metabolomics can give broader knowledge about tumor biology which consequently provides novel biomarkers and indicates new therapeutic targets. Recently, metabolomics and proteomics have extensively been applied in the field of oncology. In the context of PM, human studies, with the use of mass spectrometry (MS) which allows the detection of thousands of molecules in a large number of samples, are the most valuable. Such studies, focused on cancer biomarkers discovery or patients' stratification, are presented in this review. Moreover, the technical aspects of MS-based clinical proteomics and metabolomics are described.

Metabolic rearrangements in primary liver cancers: cause and consequences

Primary liver cancer (PLC) is the fourth most frequent cause of cancer-related death. The high mortality rates arise from late diagnosis and the limited accuracy of diagnostic and prognostic biomarkers. The liver is a major regulator, orchestrating the clearance of toxins, balancing glucose, lipid and amino acid uptake, managing whole-body metabolism and maintaining metabolic homeostasis. Tumour onset and progression is frequently accompanied by rearrangements of metabolic pathways, leading to dysregulation of metabolism. The limitation of current therapies targeting PLCs, such as hepatocellular carcinoma and cholangiocarcinoma, points towards the importance of deciphering this metabolic complexity. In this Review, we discuss the role of metabolic liver disruptions and the implications of these processes in PLCs, emphasizing their clinical relevance and value in early diagnosis and prognosis and as putative therapeutic targets. We also describe system biology approaches able to reconstruct the metabolic complexity of liver diseases. We also discuss whether metabolic rearrangements are a cause or consequence of PLCs, emphasizing the opportunity to clinically exploit the rewired metabolism. In line with this idea, we discuss circulating metabolites as promising biomarkers for PLCs.

Efficacy and safety of nivolumab for metastatic biliary tract cancer

Objective

PD-1 inhibitors have improved efficacy in many cancers. There are currently no reports of the use of PD-1 inhibitors, such as nivolumab, for metastatic biliary tract cancer (mBTC). This study reviewed the efficacy and safety of nivolumab for mBTC with the aim of exploring ways to improve efficacy and survival.

Methods

Thirty patients with mBTC were voluntarily treated with nivolumab at the PLA General Hospital. Nivolumab 3 mg/kg was administered. Progression-free survival (PFS) and overall survival were evaluated by Kaplan-Meier and univariate and multivariate analyses were carried out for clinical characteristics. Objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (AEs) were also evaluated.

Results

The median treatment cycle is four cycles. One case was complete response, 5 cases partial response, 12 cases stable, and 12 cases progression. ORR was 20%, DCR was 60%, and PFS was 3.1 months (95% CI: 2.13-4.06). The AEs of nivolumab monotherapy were fatigue (three cases), fever (two cases), hypothyroidism (one case), skin reaction (one case), and liver injury (one case). Nivolumab combined with chemotherapy related grade 1-2 hematologic toxicity were leukopenia (five cases) and thrombocytopenia (two cases), and grade 3-4 were leukopenia (three cases). Non-hematologic toxicity grade 1-2 were nausea and vomiting (four cases), fatigue (four cases), fever (three cases), peripheral neurotoxicity (three cases), and hypothyroidism (one case). Univariate analysis showed that PFS of nivolumab combined with chemotherapy was statistically significant compared with that of nivolumab monotherapy (4.1 vs 2.3 months, P=0.031). Programmed death-ligand 1 (PD-L1) expression positively has no relationship with better PFS in contrast with PD-L1 negatively (3.6 vs 3.0 months P>0.05). Multivariate analysis show nivolumab combined with chemotherapy was only the independent factor for longer PFS (HR: 0.432, P<0.05).

Conclusion

The safety of nivolumab in mBTC is controllable. Further selection of superior populations is needed to improve the efficacy of nivolumab in mBTC.