16 research outputs found
Short-chain fatty acid level and field cancerization show opposing associations with enteroendocrine cell number and neuropilin expression in patients with colorectal adenoma
BACKGROUND: Previous reports have suggested that the VEGF receptor neuropilin-1 (NRP-1) is expressed in a singly dispersed subpopulation of cells in the normal colonic epithelium, but that expression becomes dysregulated during colorectal carcinogenesis, with higher levels in tumour suggestive of a poor prognosis. We noted that the spatial distribution and morphology if NRP-1 expressing cells resembles that of enteroendocrine cells (EEC) which are altered in response to disease state including cancer and irritable bowel syndrome (IBS). We have shown that NRP-1 is down-regulated by butyrate in colon cancer cell lines in vitro and we hypothesized that butyrate produced in the lumen would have an analogous effect on the colon mucosa in vivo. Therefore we sought to investigate whether NRP-1 is expressed in EEC and how NRP-1 and EEC respond to butyrate and other short-chain fatty acids (SCFA - principally acetate and propionate). Additionally we sought to assess whether there is a field effect around adenomas. METHODOLOGY: Biopsies were collected at the mid-sigmoid, at the adenoma and at the contralateral wall (field) of 28 subjects during endoscopy. Samples were fixed for IHC and stained for either NRP-1 or for chromogranin A (CgA), a marker of EEC. Stool sampling was undertaken to assess individuals' butyrate, acetate and propionate levels. RESULT: NRP-1 expression was inversely related to SCFA concentration at the colon landmark (mid-sigmoid), but expression was lower and not related to SCFA concentration at the field. Likewise CgA+ cell number was also inversely related to SCFA at the landmark, but was lower and unresponsive at the field. Crypt cellularity was unaltered by field effect. A colocalisation analysis showed only a small subset of NRP-1 localised with CgA. Adenomas showed extensive, weaker staining for NRP-1 which contrastingly correlated positively with butyrate level. Field effects cause this relationship to be lost. Adenoma tissue shows dissociation of the co-regulation of NRP-1 and EEC. CONCLUSION: NRP-1 is inversely associated with levels of butyrate and other SCFA in vivo and is expressed in a subset of CgA expressing cells. EEC number is related to butyrate level in the same way
Influence of washing and quenching in profiling the metabolome of adherent mammalian cells: A case study with the metastatic breast cancer cell line MDA-MB-231
Metabolome characterisation is a powerful tool in oncology. To obtain a valid description of the intracellular
metabolome, two of the preparatory steps are crucial, namely washing and quenching. Washing
must effectively remove the extracellular media components and quenching should stop the metabolic
activities within the cell, without altering the membrane integrity of the cell. Therefore, it is important to
evaluate the efficiency of the washing and quenching solvents. In this study, we employed two previously
optimised protocols for simultaneous quenching and extraction, and investigated the effects of a number
of washing steps/solvents and quenching solvent additives, on metabolite leakage from the adherent
metastatic breast cancer cell line MDA-MB-231. We explored five washing protocols and five quenching
protocols (including a control for each), and assessed for effectiveness by detecting ATP in the medium
and cell morphology changes through scanning electron microscopy (SEM) analyses. Furthermore, we
studied the overall recovery of eleven different metabolite classes using the GC-MS technique and compared
the results with those obtained from the ATP assay and SEM analysis. Our data demonstrate that a
single washing step with PBS and quenching with 60% methanol supplemented with 70 mM HEPES
(−50 °C) results in minimum leakage of intracellular metabolites. Little or no interference of PBS (used in
washing) and methanol/HEPES (used in quenching) on the subsequent GC-MS analysis step was noted.
Together, these findings provide for the first time a systematic study into the washing and quenching
steps of the metabolomics workflow for studying adherent mammalian cells, which we believe will
improve reliability in the application of metabolomics technology to study adherent mammalian cell
metabolism
Genetic Background Can Result in a Marked or Minimal Effect of Gene Knockout (GPR55 and CB2 Receptor) in Experimental Autoimmune Encephalomyelitis Models of Multiple Sclerosis
PMCID: PMC379391
Tennessee: Oral Interview with Mary A. Anderson (Part 1 of 2)
Oral interview conducted with Tennessee legislator Mary A. Anderson for the Southern Women Legislators Project
Tennessee: Oral Interview with Mary A. Anderson (Part 2 of 2)
Oral interview conducted with Tennessee legislator Mary A. Anderson for the Southern Women Legislators Project
Short-chain fatty acid level and field cancerization show opposing associations with enteroendocrine cell number and neuropilin expression in patients with colorectal adenoma
Abstract Background Previous reports have suggested that the VEGF receptor neuropilin-1 (NRP-1) is expressed in a singly dispersed subpopulation of cells in the normal colonic epithelium, but that expression becomes dysregulated during colorectal carcinogenesis, with higher levels in tumour suggestive of a poor prognosis. We noted that the spatial distribution and morphology if NRP-1 expressing cells resembles that of enteroendocrine cells (EEC) which are altered in response to disease state including cancer and irritable bowel syndrome (IBS). We have shown that NRP-1 is down-regulated by butyrate in colon cancer cell lines in vitro and we hypothesized that butyrate produced in the lumen would have an analogous effect on the colon mucosa in vivo. Therefore we sought to investigate whether NRP-1 is expressed in EEC and how NRP-1 and EEC respond to butyrate and other short-chain fatty acids (SCFA - principally acetate and propionate). Additionally we sought to assess whether there is a field effect around adenomas. Methodology Biopsies were collected at the mid-sigmoid, at the adenoma and at the contralateral wall (field) of 28 subjects during endoscopy. Samples were fixed for IHC and stained for either NRP-1 or for chromogranin A (CgA), a marker of EEC. Stool sampling was undertaken to assess individuals' butyrate, acetate and propionate levels. Result NRP-1 expression was inversely related to SCFA concentration at the colon landmark (mid-sigmoid), but expression was lower and not related to SCFA concentration at the field. Likewise CgA+ cell number was also inversely related to SCFA at the landmark, but was lower and unresponsive at the field. Crypt cellularity was unaltered by field effect. A colocalisation analysis showed only a small subset of NRP-1 localised with CgA. Adenomas showed extensive, weaker staining for NRP-1 which contrastingly correlated positively with butyrate level. Field effects cause this relationship to be lost. Adenoma tissue shows dissociation of the co-regulation of NRP-1 and EEC. Conclusion NRP-1 is inversely associated with levels of butyrate and other SCFA in vivo and is expressed in a subset of CgA expressing cells. EEC number is related to butyrate level in the same way.</p
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The relationship between semaphorin 3C and microvessel density in the progression of breast and oral neoplasia
This study aimed to identify the expression of semaphorin 3C (SEMA3C) in the normal-metastatic spectrum of breast and oral cancers, and correlate expression with microvessel density (MVD, CD31), a surrogate marker of angiogenesis. Histological analysis revealed that SEMA3C expression was reduced in the development of oral cancer from normal oral tissue (P. <. 0.0001) and expression was inversely correlated with MVD (r. =. -. 0.394, P. =. 0.05). In contrast, SEMA3C expression increased in the transition from normal to invasive breast disease in epithelial/tumour cells (P. =. 0.001) and endothelial cells (P. =. 0.006), with both correlating weakly with MVD (r. =. 0.35, p. =. 0.03 and r. =. 0.243, p. =. 0.041 respectively). Furthermore, histological analysis of a breast cancer tissue microarray revealed a weak positive correlation with tumour grade (r. =. 0.305, P. =. <. 0.001) and biological phenotype (r. =. 0.237, p. =. 0.004) with tumour cell expression of SEMA3C highest in triple negative and ER. -, PR. -, HER2. + subtypes. These data suggest that SEMA3C expression is differentially regulated in the development and progression of breast versus oral neoplasia, and that increased expression of SEMA3C may be modulating breast cancer progression and angiogenesis, and could represent a biomarker of metastatic disease. © 2015 Elsevier Inc