Metabolic system alterations in pancreatic cancer patient serum: potential for early detection.

BACKGROUND: The prognosis of pancreatic cancer (PC) is one of the poorest among all cancers, due largely to the lack of methods for screening and early detection. New biomarkers for identifying high-risk or early-stage subjects could significantly impact PC mortality. The goal of this study was to find metabolic biomarkers associated with PC by using a comprehensive metabolomics technology to compare serum profiles of PC patients to healthy control subjects. METHODS: A non-targeted metabolomics approach based on high-resolution, flow-injection Fourier transform ion cyclotron resonance mass spectrometry (FI-FTICR-MS) was used to generate comprehensive metabolomic profiles containing 2478 accurate mass measurements from the serum of Japanese PC patients (n=40) and disease-free subjects (n=50). Targeted flow-injection tandem mass spectrometry (FI-MS/MS) assays for specific metabolic systems were developed and used to validate the FI-FTICR-MS results. A FI-MS/MS assay for the most discriminating metabolite discovered by FI-FTICR-MS (PC-594) was further validated in two USA Caucasian populations; one comprised 14 PCs, six intraductal papillary mucinous neoplasms (IPMN) and 40 controls, and a second comprised 1000 reference subjects aged 30 to 80, which was used to create a distribution of PC-594 levels among the general population. RESULTS: FI-FTICR-MS metabolomic analysis showed significant reductions in the serum levels of metabolites belonging to five systems in PC patients compared to controls (all p<0.000025). The metabolic systems included 36-carbon ultra long-chain fatty acids, multiple choline-related systems including phosphatidylcholines, lysophosphatidylcholines and sphingomyelins, as well as vinyl ether-containing plasmalogen ethanolamines. ROC-AUCs based on FI-MS/MS of selected markers from each system ranged between 0.93 ±0.03 and 0.97 ±0.02. No significant correlations between any of the systems and disease-stage, gender, or treatment were observed. Biomarker PC-594 (an ultra long-chain fatty acid), was further validated using an independently-collected US Caucasian population (blinded analysis, n=60, p=9.9E-14, AUC=0.97 ±0.02). PC-594 levels across 1000 reference subjects showed an inverse correlation with age, resulting in a drop in the AUC from 0.99 ±0.01 to 0.90 ±0.02 for subjects aged 30 to 80, respectively. A PC-594 test positivity rate of 5.0% in low-risk reference subjects resulted in a PC sensitivity of 87% and a significant improvement in net clinical benefit based on decision curve analysis. CONCLUSIONS: The serum metabolome of PC patients is significantly altered. The utility of serum metabolite biomarkers, particularly PC-594, for identifying subjects with elevated risk of PC should be further investigated.

Safety and immunogenicity of a 30-valent M protein-based group a streptococcal vaccine in healthy adult volunteers: A randomized, controlled phase I study.

BACKGROUND: Streptococcus pyogenes (group A Streptococcus, Strep A) is a widespread pathogen that continues to pose a significant threat to human health. The development of a Strep A vaccine remains an unmet global health need. One of the major vaccine strategies is the use of M protein, which is a primary virulence determinant and protective antigen. Multivalent recombinant M protein vaccines are being developed with N-terminal M peptides that contain opsonic epitopes but do not contain human tissue cross-reactive epitopes. METHODS: We completed a Phase I trial of a recombinant 30-valent M protein-based Strep A vaccine (Strep A vaccine, StreptAnova™) comprised of four recombinant proteins containing N-terminal peptides from 30 M proteins of common pharyngitis and invasive and/or rheumatogenic serotypes, adjuvanted with aluminum hydroxide. The trial was observer-blinded and randomized in a 2:1 ratio for intramuscular administration of Strep A vaccine or an alum-based comparator in healthy adult volunteers, at 0, 30 and 180 days. Primary outcome measures were assessments of safety, including assays for antibodies that cross-reacted with host tissues, and immunogenicity assessed by ELISA with the individual vaccine peptides and by opsonophagocytic killing (OPK) assays in human blood. RESULTS: Twenty-three Strep A-vaccinated participants and 13 controls completed the study. The Strep A vaccine was well-tolerated and there was no clinical evidence of autoimmunity and no laboratory evidence of tissue cross-reactive antibodies. The vaccine was immunogenic and elicited significant increases in geometric mean antibody levels to 24 of the 30 component M antigens by ELISA. Vaccine-induced OPK activity was observed against selected M types of Strep A in vaccinated participants that seroconverted to specific M peptides. CONCLUSION: The Strep A vaccine was well tolerated and immunogenic in healthy adults, providing strong support for further clinical development. [ClinicalTrials.gov NCT02564237].

A Randomized Controlled Study to Evaluate the Safety and Reactogenicity of a Novel rVLP-Based Plant Virus Nanoparticle Adjuvant Combined with Seasonal Trivalent Influenza Vaccine Following Single Immunization in Healthy Adults 18-50 Years of Age.

Inactivated influenza vaccines efficacy is variable and often poor. We conducted a phase 1 trial (NCT02188810), to assess the safety and immunogenicity of a novel nanoparticle Toll-like receptor 7/8 agonist adjuvant (Papaya Mosaic Virus) at different dose levels combined with trivalent influenza vaccine in healthy persons 18-50 years of age. Hemagglutination-inhibition assays, antibody to Influenza A virus nucleoprotein and peripheral blood mononuclear cells for measurement of interferon-gamma ELISPOT response to influenza antigens, Granzyme B and IFNγ:IL-10 ratio were measured. The most common adverse events were transient mild to severe injection site pain and no safety signals were observed. A dose-related adjuvant effect was observed. Geometric mean hemagglutination-inhibition titers increased at day 28 in most groups and waned over time, but fold-antibody responses were poor in all groups. Cell mediated immunity results were consistent with humoral responses. The Papaya Mosaic Virus adjuvant in doses of 30 to 240 µg combined with reduced influenza antigen content was safe with no signals up to 3 years after vaccination. A dose-related adjuvant effect was observed and immunogenicity results suggest that efficacy study should be conducted in influenza antigen-naïve participants.

Serum Metabolite Profiling for the Detection of Pancreatic Cancer: Results of a Large Independent Validation Study.

OBJECTIVES: To improve the detection of pancreatic cancer (PC), a robust diagnostic biomarker is essential. We have previously discovered 4 serum metabolites (PC-594, lysophosphatidylcholine, phosphatidylcholine, and sphingomyelin) in distinguishing patients with PC from healthy controls. Here, we report the results of our validation phase by using larger numbers of independent and blinded samples. METHODS: We collected 3 mL of serum from 116 patients with PC and 138 healthy controls. Samples were blinded and expression of the 4 candidate metabolites in each sample was determined by triple quadrupole tandem mass spectrometry. We then used cutoffs established in the discovery phase to predict the disease state of each of the validation samples. RESULTS: All 4 metabolites showed significantly lower expression in patients with PC compared with healthy controls. PC-594 showed 73.3% sensitivity and 92.0% specificity, whereas the other 3 metabolites showed 58.6% and 92.0%, 76.7% and 69.6%, and 58.6% and 81.9% sensitivity and specificity, respectively. Area under the receiver operating characteristic curve for PC-594 alone was 0.92, whereas a combination method using all 4 metabolites showed 86.2% sensitivity and 84.8% specificity. CONCLUSIONS: Our validation results confirmed that a reduction in PC-594, along with 3 other serum-based choline metabolites, is highly associated with PC.

Novel plasma phospholipid biomarkers of autism: mitochondrial dysfunction as a putative causative mechanism.

Autism is a neurological disorder that manifests as noticeable behavioral and developmental abnormalities predominantly in males between the ages of 2 and 10. Although the genetics, biochemistry and neuropathology of this disease have been extensively studied, underlying causal factors to this disease have remained elusive. Using a longitudinal trial design in which three plasma samples were collected from 15 autistic and 12 non-autistic age-matched controls over the course of 1 year, universal and unambiguous alterations in lipid metabolism were observed. Biomarkers of fatty acid elongation and desaturation (poly-unsaturated long chain fatty acids (PUFA) and/or saturated very long chain fatty acids (VLCFA)-containing ethanolamine phospholipids) were statistically elevated in all autistic subjects. In all 8 of the affected/non-affected sibling pairs, the affected sibling had higher levels of these biomarkers than the unaffected sibling. Exposure of neurons, astrocytes and hepatocytes in vitro to elevated extracellular glutamate levels resulted in lipid biomarker changes indistinguishable from those observed in autistic subjects. Glutamate stress also resulted in in vitro decreased levels of reduced glutathione (GSH), methionine and cysteine, in a similar way to the decreases we observed in autism plasma. Impaired mitochondrial fatty acid oxidation, elevated plasma VLCFAs, and glutamate toxicity as putative causal factors in the biochemistry, neuropathology, and gender bias in autism are discussed.

RIZ1 is potential CML tumor suppressor that is down-regulated during disease progression.

BACKGROUND: RIZ1 expression and activity are reduced in many cancers. In AML cell lines and patient material, RIZ1 expression is reduced relative to normal bone marrow. In chronic myelogenous leukemia (CML), blastic transformation is associated with loss of heterozygosity in the region where RIZ1 is located. RIZ1 is a PR domain methyltransferase that methylates histone H3 lysine 9, a modification important for transcriptional repression. In CML blast crisis cell lines RIZ1 represses insulin-like growth factor-1 expression and autocrine signaling. Together these observations suggest that RIZ1 may have a role in the chronic phase to blast crisis transition in CML. RESULTS: In CML patient material, we observed that RIZ1 expression was decreased during progression from chronic phase to blast crisis. RIZ1 was expressed in mature myeloid and CD34+ cells demonstrating that decreased RIZ1 expression in blast crisis is not due to an increased immature cell population. Expression of RIZ1 CML blast crisis cell lines decreased proliferation, increased apoptosis, and enhanced differentiation. CONCLUSION: RIZ1 is a candidate tumor suppressor gene whose expression is decreased in blast crisis. Loss of RIZ1 activity results in decreased apoptosis and differentiation and enhanced proliferation. Together these results suggest that loss of RIZ1 expression will lead to an increase in myeloid blast cell population resulting in CML progression.