Metabolic consequences of p300 gene deletion in human colon cancer cells.
Metabolite profiling using (1)H nuclear magnetic resonance (NMR) spectroscopy was used to investigate the metabolic changes associated with deletion of the gene for the transcriptional coactivator p300 in the human colon carcinoma cell line HCT116. Multivariate statistical methods were used to distinguish between metabolite patterns that were dependent on cell growth conditions and those that were specifically associated with loss of p300 function. In the absence of serum, wild-type cells showed slower growth, which was accompanied by a marked decrease in phosphocholine concentration, which was not observed in otherwise isogenic cell lines lacking p300. In the presence of serum, several metabolites were identified as being significantly different between the two cell types, including glutamate and glutamine, a nicotinamide-related compound and glycerophosphocholine (GPC). However, in the absence of serum, these metabolites, with the exception of GPC, were not significantly different, leading us to conclude that most of these changes were context dependent. Transcript profiling, using DNA microarrays, showed changes in the levels of transcripts for several enzymes involved in choline metabolism, which might explain the change in GPC concentration. Localized in vivo (1)H NMR measurements on the tumors formed following s.c. implantation of these cells into mice showed an increase in the intensity of the peak from choline-containing compounds in the p300(-) tumors. These data show that NMR-based metabolite profiling has sufficient sensitivity to identify the metabolic consequences of p300 gene deletion in tumor cells in vitro and in vivo.
Bundy
Jacob G
JG
Department of Biochemistry, Hutchison/Medical Research Council Research Centre, University of Cambridge, 80 Tennis Court Road, Cambridge, United Kingdom.
Iyer
N Gopalakrishna
NG
Gentile
Michelle S
MS
Hu
De-En
DE
Kettunen
Mikko
M
Maia
Ana-Teresa
AT
Thorne
Natalie P
NP
Brenton
James D
JD
Caldas
Carlos
C
Brindle
Kevin M
KM
D000818:Animals; D003110:Colonic Neoplasms / Q000235:genetics* / Q000378:metabolism*; D017077:Culture Media, Conditioned; D017353:Gene Deletion; D020869:Gene Expression Profiling; D045325:HCT116 Cells; D006801:Humans; D051379:Mice; D016513:Mice, SCID; D019906:Nuclear Magnetic Resonance, Biomolecular; D014183:Transplantation, Heterologous; D050880:p300-CBP Transcription Factors / Q000172:deficiency* / Q000235:genetics
D017077:Culture Media, Conditioned; D050880:p300-CBP Transcription Factors