Abstract 4926: Preclinical intratumoral pharmacokinetics (PK) of capecitabine (Cap) given +/- eribulin (Eri)

Background: Eri & Cap are active as single agents in metastatic breast cancer, but the combination appears particularly active & well tolerated clinically. We explored the hypothesis that normalisation of tumor vasculature by Eri seen in preclinical models may enhance delivery of Cap to the tumor when given in combination.

Methods: Mice bearing MDA-MD-231 xenografts were treated with Cap 540mg/kg p.o. day 1 alone or following Eri 1mg/kg i.v. on day -8 then sacrificed on day 1 at 15min, 30min, 1h, 2h, 4h, 6h or 24h after Cap (n=3/ time point). Concentrations of Cap & its metabolites (5'-deoxy-5-fluorocytidine, 5DFCR; 5-Fluoro-5'-deoxyuridine, 5DFUR; 5-Fluorouracil, 5FU; 5-Fluorouridine, 5FUrd; & 5-Fluoro-2'-deoxyuridine, 5FdUrd) in plasma, tumor, skin & muscle were analysed by LC-MS/MS. Half the tumor was reserved to study Cap distribution using matrix-assisted laser desorption/ionization mass spectrometry imaging with haem imaged as a surrogate marker for tumour vasculature.

Results: We found no differences in the plasma, skin, muscle or tumor PK profiles of Cape & its metabolites with the addition of Eri (Table 1). In both treatment arms intratumoral concentrations of 5DFUR, 5FU, 5FUrd & 5FdUrd appeared higher in tumors while those of Cape & 5DFCR appeared higher in normal healthy tissues. To mitigate the variability in tumor Cape concentrations between animals, we also expressed the results as the ratio of drug concentration in tumour:healthy tissue but again found no apparent effect of Eri on intratumoral drug concentrations. Analyses of drug distribution are on-going & will be presented.

Conclusion: No clear effect of Eri on intratumoral concentrations of Cape or its metabolites was seen. We are exploring potential differences in tumour drug distribution.

Citation Format: Maria Jove Casulleras, Jade Spencer, Paul Loadman, Malcolm Clench, Steve Shnyder, Patricia Cooper, Cristina Russo, Amanda Race, Ramon Salazar, Chris Twelves. Preclinical intratumoral pharmacokinetics (PK) of capecitabine (Cap) given +/- eribulin (Eri) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4926.

Abstract 4231: Analysis of FFPE treated clinical tissue sections obtained from human intraocular malignancy, uveal melanoma by mass spectrometry imaging (MSI)

Introduction

Clinical research into human intraocular disease UM FFPE tissue sections is described. UM remains the most common intraocular malignancy in adults, with poor prognosis for UM within the choroid region and distant sites UM metastasis. Two imaging MS techniques Matrix Assisted Laser Desorption/Ionisation (MALDI) and Desorption Electrospray Ionisation (DESI) MSI were applied. Molecular profiles were obtained and analysed by multivariate statistical approaches, providing insight into the biochemical and biological differences/similarities within the patient sample cohort (n = 15).

Methods

Enucleations were collected over 6 years and subjected to the standard fixation and paraffin embedding protocols. In preparation for MS, 5 μm sections were produced with removal of the paraffin followed by heat induced antigen retrieval.

MALDI MSI tissue sections were prepared by applying a matrix solution onto the tissue sections to help ionization of molecules directly from the tissue. All MSI experiments (MALDI and DESI) were carried out using a SYNAPT mass spectrometer (Waters Corporation, Manchester, UK). Multivariate analyses were performed using MATLAB (MathWorks, Inc., Natick, MA, US) and the Eigenvector PLS_Toolbox.

Results

Initial MALDI MSI images acquired with a spatial resolution of 100 μm x 100 μm in positive ion mode showed distinct spatial distribution of many molecular species throughout the choroid, cornea, retina, lens and UM tumor regions. Further MALDI MSI experiments using consecutive tissue sections at 50 μm x 50 μm spatial resolution show substantial variation in the spatial distribution of species within the low molecular mass range. DESI MSI experiments were carried out at 200 μm x 200 μm in negative ionization mode. Deprotonated molecular ions were detected from a variety of lipid related species, localized to specific regions within the eye including the tumor region.

Multivariate analysis classified UM samples (good vs. poor prognosis). Using unsupervised PCA, an unbiased representation of the data was generated, with clear sample grouping and differentiation observed based upon tumor status. Use of the supervised PLS-DA technique provided even clearer separation between the selected samples, with tumor profiles displaying dominant discriminatory peaks. These peaks could be identified as sphingolipids and Lyso-phosphocholine, a phosphatidylcholine degradation product.

Conclusions

It was possible to analyze clinical research FFPE tissue sections by MALDI and DESI MSI, illustrating that specific small molecular species remained localized to certain tissue types including the UM tumor. Initial correlation with tumor status was determined from the statistical analysis of the MALDI MSI datasets.

Citation Format: Laura M. Cole, Hardeep S. Mudhar, Karen Sisley, Andrew Peck, Mike Batey, Emmanuelle Claude, Malcolm Clench. Analysis of FFPE treated clinical tissue sections obtained from human intraocular malignancy, uveal melanoma by mass spectrometry imaging (MSI). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4231.

Polyphenols are responsible for the proapoptotic properties of pomegranate juice on leukemia cell lines

Pomegranates have shown great promise as anti-cancer agents in a number of cancers including clinical trials in prostate cancer. We have previously shown pomegranate juice (PGJ) induced apoptosis and preferentially alters the cell cycle in leukemia cell lines compared with nontumor control cells. However, the agents responsible have not yet been fully elucidated. Treatment of four leukemia cell lines with five fractions obtained from PGJ by solid phase extraction demonstrated that only the acetonitrile fractions decreased adenosine triphosphate (ATP) levels in all leukemia cell lines. Acetonitrile fractions also significantly activated caspase-3 and induced nuclear morphology characteristic of apoptosis. S phase arrest was induced by acetonitrile fractions which matched S phase arrest seen previously following whole PGJ treatments. The acetonitrile fractions contained higher phenol content than whole PGJ whereas only low levels of phenols were seen in any other fraction. Liquid chromatography mass spectrometry (LC–MS) analysis demonstrated that acetonitrile fractions were enriched in ellagitannins, ellagic acid, and hydroxycinnamic acid derivatives but depleted in anthocyanins. Individual treatments with identified compounds demonstrated that the ellagitannin: punicalagin was the most active and mimicked the responses seen following acetonitrile fraction treatment. Bioactive components within pomegranate were confined to the acetonitrile fraction of PGJ. The enrichment in ellagitannins and hydroxycinnamic acids suggest these may provide the majority of the bioactivities of PGJ. Individual treatments with compounds identified demonstrated that the ellagitannin: punicalagin was the most active agent, highlighting this compound as a key bioactive agent in PGJ.

A novel compound from celery seed with a bactericidal effect against Helicobacter pylori

Objectives

The aim was to purify and characterise an antimicrobial component from celery (Apium graveolens) seeds, which have been used for centuries as a herbal medicine with reported antibacterial effects.

Methods

A crude alcoholic extract of celery seeds was fractionated by organic solvent extractions, column chromatography and HPLC. Fractions were assayed for antimicrobial activity against the gastric pathogen Helicobacter pylori and other bacteria. The purified antibacterial component was characterised via MS and NMR. Preliminary investigation of its mechanism of action included morphological studies, incorporation of macromolecular precursors, membrane integrity and two-dimensional protein electrophoresis.

Key findings

The purified component, termed ‘compound with anti-Helicobacter activity’ (CAH), had potent bactericidal effects against H. pylori; the minimum inhibitory concentration and minimum bactericidal concentration were 3.15 μg/ml and 6.25–12.5 μg/ml, respectively. CAH (Mr = 384.23; empirical formula C24H32O4) had specific inhibitory effects on H. pylori and was not active against Campylobacter jejuni or Escherichia coli. MS and NMR data were consistent with a dimeric phthalide structure. The results appeared to rule out mechanisms that operated solely by loss of membrane integrity or inhibition of protein or nucleic acid synthesis.

Conclusions

CAH may be suitable for further investigation as a potent agent for treating H. pylori infections.

A novel compound from celery seed with a bactericidal effect against Helicobacter pylori

OBJECTIVES

The aim was to purify and characterise an antimicrobial component from celery (Apium graveolens) seeds, which have been used for centuries as a herbal medicine with reported antibacterial effects.

METHODS

A crude alcoholic extract of celery seeds was fractionated by organic solvent extractions, column chromatography and HPLC. Fractions were assayed for antimicrobial activity against the gastric pathogen Helicobacter pylori and other bacteria. The purified antibacterial component was characterised via MS and NMR. Preliminary investigation of its mechanism of action included morphological studies, incorporation of macromolecular precursors, membrane integrity and two-dimensional protein electrophoresis.

KEY FINDINGS

The purified component, termed 'compound with anti-Helicobacter activity' (CAH), had potent bactericidal effects against H. pylori; the minimum inhibitory concentration and minimum bactericidal concentration were 3.15 microg/ml and 6.25-12.5 microg/ml, respectively. CAH (M(r) = 384.23; empirical formula C(24)H(32)O(4)) had specific inhibitory effects on H. pylori and was not active against Campylobacter jejuni or Escherichia coli. MS and NMR data were consistent with a dimeric phthalide structure. The results appeared to rule out mechanisms that operated solely by loss of membrane integrity or inhibition of protein or nucleic acid synthesis.

CONCLUSIONS

CAH may be suitable for further investigation as a potent agent for treating H. pylori infections.

Localization of water-soluble carbohydrates in wheat stems using imaging matrix-assisted laser desorption ionization mass spectrometry

The pool of endogenous water-soluble oligosaccharides found in the stems of wheat (Triticum aestivum) is being investigated as a potential indicator of grain yield. Techniques such as liquid chromatography with mass spectrometry (LC-MS) can profile these analytes but provide no spatial information regarding their distribution in the wheat stem. The imaging matrix-assisted laser desorption ionization (MALDI) mass spectrometry technique has not been utilized for the analysis of oligosaccharides in plant systems previously. Imaging MALDI mass spectrometry was used to analyse cross and longitudinal sections from the stems of Triticum aestivum. A range of oligosaccharides up to Hex(11) were observed. Water-soluble oligosaccharides were ionized as potassiated molecules, and found to be located in the stem pith that is retained predominantly around the inner stem wall. Imaging MALDI analyses provided spatial information on endogenous oligosaccharides present in wheat stems. The technique was found to offer comparable sensitivities for oligosaccharide detection to those of our established LC-MS method, and has potential for broad application in studying the in situ localization of other compound types in plant material.

Studies into the formation of dioxins in the sintering process used in the iron and steel industry. 1. Characterisation of isomer profiles in particulate and gaseous emissions

Dioxin analyses using a DB5MS chromatography column are presented for samples of dust from an electrostatic precipitator and emissions from the main stack of a UK sinter plant. The analyses have been repeated using the SP2331 column, for which the elution order has been determined for the whole range of tetra to octachlorodibenzo-p-dioxins and dibenzofurans, and which provides a larger degree of separation than the DB5MS column. Polychlorinated dibenzofurans are present in significantly larger amounts in both the dust and stack emissions, and are the main contributors to the I-TEQ. Analysis using the SP2331 column for dioxins show considerable similarity to those of Bacher et al. for soot from a wood-burning fire, but differ markedly from those of Addink et al. for simulation of waste incineration. The similarities to Bacher's results are less for the dibenzofurans. Comparison of absolute concentrations with reported vapour pressures shows the retention of significant dioxin in the dust to involve mechanisms other than pure condensation.