Proton magnetic resonance spectroscopy (1H-MRS) of surgically collected tumor specimens may contribute to investigating cancer metabolism and the significance of the “total choline” (tCho) peak (3.2 ...ppm) as malignancy and therapy response biomarker. To ensure preservation of intrinsic metabolomic information, standardized handling procedures are needed. The effects of time to freeze (cold ischemia) were evaluated in (a) surgical epithelial ovarian cancer (EOC) specimens using high-resolution (HR) 1H-MRS (9.4 T) of aqueous extracts and (b) preclinical EOC samples (xenografts in SCID mice) investigated by in vivo MRI-guided 1H-MRS (4.7 T) and by HR-1H-MRS (9.4 T) of tumor extracts or intact fragments (using magic-angle-spinning (MAS) technology). No significant changes were found in the levels of 27 of 29 MRS-detected metabolites (including the tCho profile) in clinical specimens up to 2 h cold ischemia, besides an increase in lysine and a decrease in glutathione. EOC xenografts showed a 2-fold increase in free choline within 2 h cold ischemia, without further significant changes for any MRS-detected metabolite (including phosphocholine and tCho) up to 6 h. At shorter times (≤1 h), HR-MAS analyses showed unaltered tCho components, along with significant changes in lactate, glutamate, and glutamine. Our results support the view that a time to freeze of 1 h represents a safe threshold to ensure the maintenance of a reliable tCho profile in EOC specimens.
Proton magnetic resonance spectroscopy (
H-MRS) of surgically collected tumor specimens may contribute to investigating cancer metabolism and the significance of the "total choline" (
Cho) peak (3.2 ...ppm) as malignancy and therapy response biomarker. To ensure preservation of intrinsic metabolomic information, standardized handling procedures are needed. The effects of time to freeze (cold ischemia) were evaluated in (a) surgical epithelial ovarian cancer (EOC) specimens using high-resolution (HR)
H-MRS (9.4 T) of aqueous extracts and (b) preclinical EOC samples (xenografts in SCID mice) investigated by in vivo MRI-guided
H-MRS (4.7 T) and by HR-
H-MRS (9.4 T) of tumor extracts or intact fragments (using magic-angle-spinning (MAS) technology). No significant changes were found in the levels of 27 of 29 MRS-detected metabolites (including the
Cho profile) in clinical specimens up to 2 h cold ischemia, besides an increase in lysine and a decrease in glutathione. EOC xenografts showed a 2-fold increase in free choline within 2 h cold ischemia, without further significant changes for any MRS-detected metabolite (including phosphocholine and
Cho) up to 6 h. At shorter times (≤1 h), HR-MAS analyses showed unaltered
Cho components, along with significant changes in lactate, glutamate, and glutamine. Our results support the view that a time to freeze of 1 h represents a safe threshold to ensure the maintenance of a reliable
Cho profile in EOC specimens.
MicroRNAs have been found to be deregulated in several diseases and, due to their high stability in body fluids, represent promising noninvasively detectable biomarkers. However, numerous technical ...variables can affect accurate measurement of circulating miRNAs. Using a microarray-based method we assessed the: (i) adequate intra- and inter-array reproducibility of miRNA profiling; (ii) feasibility of using archival plasma samples stored for an extended period of time and available in limited amounts; (iii) good correlation between different batches; and (iv) time-dependent increase of background signals close to the chip expiration date.
Breast cancer is the most common type of cancer in women worldwide, with the luminal subtype being the most widespread. Although characterized by better prognosis compared with other subtypes, ...luminal breast cancer is still considered a threatening disease due to therapy resistance, which occurs via both cell- and non-cell-autonomous mechanisms. Jumonji domain-containing 6, arginine demethylase and lysine hydroxylase (JMJD6) is endowed with a negative prognostic value in luminal breast cancer and, via its epigenetic activity, it is known to regulate many intrinsic cancer cell pathways. So far, the effect of JMJD6 in molding the surrounding microenvironment has not been explored.Here, we describe a novel function of JMJD6 showing that its genetic inhibition in breast cancer cells suppresses lipid droplet formation and ANXA1 expression, via estrogen receptor alpha and PPARα modulation. Reduction of intracellular ANXA1 results in decreased release in the tumor microenvironment (TME), ultimately preventing M2-type macrophage polarization and tumor aggressiveness.
Our findings identify JMJD6 as a determinant of breast cancer aggressiveness and provide the rationale for the development of inhibitory molecules to reduce disease progression also through the remodeling of TME composition.
Objectives
To assess quantitatively the impact of a novel reconstruction algorithm (“kernel”) with beam-hardening correction (BHC) on beam-hardening artefacts of the myocardium at dual-energy CT ...myocardial perfusion imaging (DE-CTMPI).
Methods
Rest-series of DE-CTMPI examinations from 14 patients were retrospectively analyzed. Six image series were reconstructed for each patient: a) 100 kV, b) 140 kV, and c) linearly blended MIX
0.5
, each with BHC (D33f kernel) and without (D30f kernel). Seven hundred and fifty-six myocardial regions were assessed. Seven equal regions of interest divided the myocardium in the axial section. Three subdivisions were created within these regions in areas prone to BHA. Reports of SPECT studies performed within 30 days of CT examination were used to confirm the presence and location of true perfusion defects. Paired student
t
-test was used for statistical evaluation.
Results
Overall mean myocardial attenuation was lower using BHC (D30f: 87.3 ± 24.1 HU; D33f: 85.5 ± 21.5 HU;
p
= 0.009). Overall relative difference from average myocardial attenuation (RDMA) was more homogeneous using BHC (D30f: −0.3 ± 11.4 %; D33f: 0.1 ± 10.1 %;
p
< 0.001). Changes in RDMA were greatest in the posterobasal myocardium (D30f: −16.2 ± 10.0 %; D33f: 3.4 ± 10.7 %;
p
< 0.001).
Conclusions
A dedicated reconstruction algorithm with BHC can significantly reduce beam-hardening artefacts in DE-CTMPI.
Key Points
•
Beam-hardening artefacts (BHA) cause interference with attenuation-based CT myocardial perfusion assessment (CTMPI)
.
•
BHA occur mostly in the posterobasal left ventricular wall
.
•
Beam-hardening correction homogenized and decreased mean myocardial attenuation
.
•
BHC can help avoid false-positive findings and increase specificity of static CTMPI
.
To investigate the tumor fraction with cancer stem/tumor initiating cell (CSC/TIC) characteristics, we tested the human cervical carcinoma cell lines A431, Caski and SiHa, by growth as non-adherent ...spheres in specific media and aldehyde dehydrogenase (ALDH) enzymatic activity. A good correlation between the two parameters was observed and the highest levels were observed in A431 cell line that was selected for characterization of the CSC/TIC fraction. A431 parental cells already displayed characteristics common to CSC/TIC, such as sphere forming efficiency, adherent holoclone formation and high ALDH activity. Non-adherent spheres maintained or increased these properties, and, in particular, ALDH-positive fraction increased from 46 to 65% and a transient induction of stem cell markers such as Nanog, Nestin and Oct4 was observed. Furthermore, a significant increase of paraclone forming cells was observed, suggesting that differentiation took place inside sphere cell populations. As compared to parental cells, spheres were characterized by: (1) a ten-fold higher verapamil-sensitive side population fraction; (2) the appearance of a podoplanin-positive subpopulation characterized by a small cell size; (3) the ability to propagate tumors in nude mice at a lower cell dose. The global gene expression analysis demonstrated a strong and reversible modulation of 'sphere' phenotype in comparison to parental and sphere cells re-induced to adherent conditions. All together our results indicated that the growth of A431 cells as a non-adherent sphere was not sufficient by itself to define a stem-like population, but it was essential for the emergence of a small population of tumor cells with CSC properties.
We described a case of fatal septicemic yersiniosis in a young adult brown titi monkey (Plecturocebus brunneus) which presented lethargy and severe anemia. Postmortem external assessment revealed ...marked dehydration and pale pink mucous membranes. The main gross findings included enlarged liver with yellow pinpoints, enlarged spleen with yellow nodules, mucosal ulcerations in the large intestine, enlarged mesenteric lymph nodes, and pulmonary hemorrhage. Histology revealed necrosuppurative hepatosplenitis with intralesional colonies of rod-shaped gram-negative bacteria, ulcerative colitis, reactive lymphoid hyperplasia, and fibrinous and hemorrhagic pneumonia. Bacterial culture and identification using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry confirmed the diagnosis of yersiniosis by Yersinia enterocolitica. This study indicated that yersiniosis should be considered as a differential diagnosis of death in brown titi monkeys.
RESUMO: Descrevemos um caso de yersiniose septicêmica fatal em um zogue-zogue (Plecturocebus brunneus) jovem adulto que apresentava um quadro de letargia e anemia severa. Macroscopicamente, havia acentuada desidratação e as mucosas estavam pálidas. Notou-se hepatomegalia com múltiplos pontos amarelos e esplenomegalia com múltiplos nódulos amarelos pelo parênquima. Ainda, ulcerações da mucosa do intestino grosso, linfonodos mesentéricos aumentados e hemorragia pulmonar foram observados. A avaliação histológica revelou hepatite e esplenite necrossupurativas associadas a agregados bacterianos bacilares gram-negativos intralesionais, colite ulcerativa, hiperplasia linfoide reativa e pneumonia fibrino-hemorrágica. A cultura bacteriana e identificação através do método de espectrometria de massa por ionização e dessorção a laser assistida por matriz associada ao tempo de voo confirmou o diagnóstico de yersiniose por Yersinia enterocolitica. Este estudo demonstra que a yersiniose deve ser considerada como um diagnóstico diferencial de causa de morte em zogue-zogues.
The occurrence of drug resistance limits the efficacy of platinum compounds in the cure of ovarian carcinoma. Since microRNAs (miRNAs) may contribute to this phenomenon by regulating different ...aspects of tumor cell response, the aim of this study was to exploit the analysis of expression of miRNAs in platinum sensitive/resistant cells in an attempt to identify potential regulators of drug response. MiR-483-3p, which may participate in apoptosis and cell proliferation regulation, was found up-regulated in 4 platinum resistant variants, particularly in the IGROV-1/Pt1 subline, versus parental cells. Transfection of a synthetic precursor of miR-483-3p in IGROV-1 parental cells elicited a marked up-regulation of the miRNA levels. Growth-inhibition and colony-forming assays indicated that miR-483-3p over-expression reduced cell growth and conferred mild levels of cisplatin resistance in IGROV-1 cells, by interference with their proliferative potential. Predicted targets of miR-483-3p included PRKCA (encoding PKC-alpha), previously reported to be associated to platinum-resistance in ovarian carcinoma. We found that miR-483-3p directly targeted PRKCA in IGROV-1 cells. In keeping with this finding, cisplatin sensitivity of IGROV-1 cells decreased upon molecular/pharmacological inhibition of PKC-alpha. Overall, our results suggest that overexpression of miR-483-3p by ovarian carcinoma platinum-resistant cells may interfere with their proliferation, thus protecting them from DNA damage induced by platinum compounds and ultimately representing a drug-resistance mechanism. The impairment of cell growth may account for low levels of drug resistance that could be relevant in the clinical setting.
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•miR-483-3p is up-regulated in ovarian carcinoma cells resistant to platinum drugs.•Ectopic expression of miR-483-3p in IGROV-1 confers mild levels of Pt-resistance.•Overexpression of miR-483-3p down-regulates PRKCA levels in ovarian carcinoma cells.•miR 483–3p directly targets PRKCA 3′UTR in IGROV-1 cells.•The contribution of miR-483-3p to Pt-resistance is related to cell proliferation.
Genome-wide gene expression analyses of tumors are a powerful tool to identify gene signatures associated with biologically and clinically relevant characteristics and for several tumor types are ...under clinical validation by prospective trials. However, handling and processing of clinical specimens may significantly affect the molecular data obtained from their analysis. We studied the effects of tissue handling time on gene expression in human normal and tumor colon tissues undergoing routine surgical procedures.
RNA extracted from specimens of 15 patients at four time points (for a total of 180 samples) after surgery was analyzed for gene expression on high-density oligonucleotide microarrays. A mixed-effects model was used to identify probes with different expression means across the four different time points. The p-values of the model were adjusted with the Bonferroni method.
Thirty-two probe sets associated with tissue handling time in the tumor specimens, and thirty-one in the normal tissues, were identified. Most genes exhibited moderate changes in expression over the time points analyzed; however four of them were oncogenes, and two confirmed the effect of tissue handling by independent validation.
Our results suggest that a critical time point for tissue handling in colon seems to be 60 minutes at room temperature. Although the number of time-dependent genes we identified was low, the three genes that already showed changes at this time point in tumor samples were all oncogenes, hence recommending standardization of tissue-handling protocols and effort to reduce the time from specimen removal to snap freezing accounting for warm ischemia in this tumor type.
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