Figure legends
Figure 1 Schematic diagram of the sampling, quenching and
extraction procedures for Hela cells from 2D monolayer cultures and 3D
MTS.
Figure 2 Parameters evaluated during the optimization of
metabolome extraction and analysis conditions. The cell collection
procedure remains constant for all different combinations of metabolome
quenching, extraction and GC/LC-MS analysis. Metabolic quenching is
achieved by adding quenchers to the cells. Then, cell separation and
metabolite extraction are performed at the same time by scraping the
cells in different extraction solvents.
Figure 3 Comparison of the
leakage degree of metabolites in different quenchers. (a) The leakage
degree of amino acids in different quenchers; (b) The leakage degree of
organic acids, phosphate sugars, adenosine nucleotide and coenzymes in
different quenchers. Values were the mean of three biological
replicates. Error bars represented standard deviation.
Figure 4 The relationship between the degree of leakage and
molecular weight in 2D cells. The degree of leakage was calculated based
on the level of metabolites in the quencher and the overall metabolite
level (quencher + extractant).
Figure 5 The total number of metabolites obtained by each
extraction method.
Figure 6 The sum of the different kind metabolites identified
in cell extracts only in 2D cells. Significant analysis was performed
against N2-A group.
Figure 7 Eighteen amino acids were identified in 12
quenching-extraction methods. Values were the mean of three biological
replicates. Error bars represented standard deviation.
Figure 8 Eight organic
acids, nine sugar phosphates, eight adenosine nucleotides and coenzymes
were identified in twelve extraction methods. Values were the mean of
three biological replicates. Error bars represented standard deviation.
Figure 9 The application of 12 intracellular extraction methods
on 3D MTSs. (A) Heat map of the
degree of leakage of the two quenchers in 3D MTSs; (B) 43 metabolites
were identified in twelve extraction methods in 3D MTSs.
Figure 10 The measured concentrations of extracellular:
glucose, glutamine, ammonium and lactate. The culture time of 2D cells
and 3D MTSs was shown on the bottom and top axis, respectively.
Figure 11 Heat map of the absolute amount of metabolites. The
2D/3D cells were treated with a medium containing 1 μM of DOX for 48 h.
Figure 12 Kyoto Encyclopedia of Genes and Genomes (KEGG)
pathways affected by DOX using pathway enrichment with the MetaboAnalyst
pathway analysis module.