title: Decreased cellular levels of palmitic amide are linked to 5-fluorouracil resistance in human colon cancer cells.
abstract: OBJECTIVE
  The aim of this study was to investigate whether profiling metabolic compounds in human colon cancer cells with induced 5-florouracil resistance enables identification of predictive biomarkers for 5-florouracil resistance.
  
  
  METHODS
  5-florouracil resistant and parental cells were extracted using methanol/chloroform solution, and analyzed by MALDI-TOF. Principal components analysis and discriminant analysis was performed to select low-mass ions with strong discriminating power between 5-florouracil resistant and parental cells. The correlation between the intensities of low-mass ions and intrinsic 5-florouracil resistance in 11 colon cancer cells was analyzed using the Spearman rank coefficient.
  
  
  RESULTS
  Eleven low-mass ions had strong discrimi-nating power between 5-florouracil-resistant and parental cells. Of these, the intensity of a low-mass ion with 256.29 m/z was negatively correlated with intrinsic 5-florouracil resistance in 11 colon cancer cells (r = -0.6545, P = 0.0338). By searching the H+ adduct with 0.05 m/z tolerance in the Human Metabolome Database, a low-mass ion of 256.29 m/z was identified as palmitic amide. Interestingly, extracellular treatment with palmitic amide reduced 5-florouracil resistance and invasiveness in 5-florouracil-resistant cells.
  
  
  CONCLUSIONS
  Palmitic amide showed potential not only as a predictor of 5-florouracil resistance, but also for reduction of 5-florouracil resistance in colon cancer cells.
authors.forename: Jun Hwa
authors.initials: JH
authors.lastname: Lee
authors.forename: Seung Cheol
authors.initials: SC
authors.lastname: Kim
authors.forename: Kyung-Hee
authors.initials: KH
authors.lastname: Kim
authors.forename: Won Ki
authors.initials: WK
authors.lastname: Kim
authors.forename: Min Jun
authors.initials: MJ
authors.lastname: Lee
authors.forename: Byong Chul
authors.initials: BC
authors.lastname: Yoo
authors.forename: Seung-Gu
authors.initials: SG
authors.lastname: Yeo
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D014408:Biomarkers, Tumor / Q000378:metabolism; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D019008:Drug Resistance, Neoplasm; D004357:Drug Synergism; D005472:Fluorouracil / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D010169:Palmitic Acids / Q000008:administration & dosage / Q000378:metabolism* / Q000494:pharmacology*; D025341:Principal Component Analysis; D015398:Signal Transduction / Q000187:drug effects; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D018709:Statistics, Nonparametric
chemical_list: D014408:Biomarkers, Tumor; D010169:Palmitic Acids; C014025:hexadecanamide; D005472:Fluorouracil