Semi-quantitative analyses of metabolic systems of human colon cancer metastatic xenografts in livers of superimmunodeficient NOG mice

Abstract

Analyses of energy metabolism in human cancer have been difficult because of rapid turnover of the metabolites and difficulties in reducing time for collecting clinical samples under surgical procedures. Utilization of xenograft transplantation of human-derived colon cancer HCT116 cells in spleens of superimmunodeficient NOD/SCID/IL-2Rγnull (NOG) mice led us to establish an experimental model of hepatic micrometastasis of the solid tumor, whereby analyses of the tissue sections collected by snap-frozen procedures through newly developed microscopic imaging mass spectrometry (MIMS) revealed distinct spatial distribution of a variety of metabolites. To perform intergroup comparison of the signal intensities of metabolites among different tissue sections collected from mice in fed states, we combined matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry (MALDI–TOF-IMS) and capillary electrophoresis–mass spectrometry (CE–MS), to determine the apparent contents of individual metabolites in serial tissue sections. The results indicated significant elevation of ATP and energy charge in both metastases and the parenchyma of the tumor-bearing livers. To note were significant increases in UDP-N-acetyl hexosamines, and reduced and oxidized forms of glutathione in the metastatic foci versus the liver parenchyma. These findings thus provided a potentially important method for characterizing the properties of metabolic systems of human-derived cancer and the host tissues in vivo.Electronic supplementary materialThe online version of this article (doi:10.1007/s00216-011-4895-5) contains supplementary material, which is available to authorized users.

Alternative splicing of CD44 mRNA by ESRP1 enhances lung colonization of metastatic cancer cell

“…4T1 lung metastasis tissues snap-frozen in liquid nitrogen were dissected to prepare cryosections with 5-µm thickness by use of a cryostat (CM 1900; Leica Microsystems, Wetzlar, Germany). The sections were thaw-mounted on indium-tin oxide slides (Bruker Daltonik GmbH, Bremen, Germany) and were dried in silica gel-containing plastic tubes and, then, sprayed with 9-aminoacridine (9-AA, 20 mg in 4 ml 70% MeOH) by use of a 0.2-mm nozzle calibre airbrush (Procon boy FWA Platinum; Mr Hobby, Tokyo, Japan) to conduct matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry in negative ion mode 34,35 . Adjacent sections were fixed with 4% buffered formalin (Nacalai Tesque, Kyoto, Japan) and stained with anti-CD44v antibody 52 .…”

“…Together, these results indicated that lung metastasis results in enrichment of ROS-resistant cells with high GSH levels. To examine whether CD44v-expressing cells maintain high GSH levels in vivo, we applied imaging mass spectrometry to visualize GSH and oxidized glutathione (GSSG) in frozen tissue samples 34,35 . CD44v + lung metastases formed by 4T1 cells manifested high levels of GSH but not of GSSG (Fig.…”

Energy Management by Enhanced Glycolysis in G1-phase in Human Colon Cancer Cells In Vitro and In Vivo

“…Cryosections (5 mm) of the liver samples were thaw-mounted on indium-tin oxide slides (8-12 ohm/sq; Sigma; ref. 27). Protocols for the abovementioned experiments were approved by Institutional Committee of Animal Care and Ethics in School of Medicine, Keio University.…”

“…Fluorescent images of metastatic foci on tissue slices were acquired with a built-in fluorescence microscope and 2 fluorescence mirror units (U-MGFPHO for green fluorescence and U-MWIG3 for red fluorescence; Olympus). Matrix application (27) and acquisition of MALDI imaging data (27) with spatial interval of 20 mm and data processing (27,28) were carried out as described previously. Measurement points with Fucci-green fluorescence were considered to be cells in S þ G 2 -M phases.…”

“…To observe changes in metabolism in cell-cycle progression in vivo, we used a NOG mouse model for liver metastasis of Fucci-HCT116 cells. With MALDI-IMS, relative concentrations of metabolites, all of which we have described as successful quantitation (27), in tumor cells were determined. Measurement points corresponding to tumor cells with Fuccigreen fluorescence (S þ G 2 -M phases) and those with Fuccired fluorescence (G 1 phase) were assigned precisely using built-in fluorescence image capturing system (Fig.…”