title: ALDH1 expression is enriched in breast cancers arising in young women but does not predict outcome.
abstract: BACKGROUND
  Tumours arising in younger women appear to be biologically more aggressive and tend to have a poorer outcome. Being relatively resistant to conventional treatments, breast cancer stem cells (CSCs) have been postulated as a possible cause of disease recurrence after treatment. In this study, we used ALDH1 as a CSC marker and determined whether ALDH1 expression correlated with clinical outcome in young women with breast cancer.
  
  
  METHODS
  The expression of ALDH1 was evaluated through immunohistochemistry on microarrayed cores obtained from 141 consecutive patients up to 35 years of age.
  
  
  RESULTS
  The expression of ALDH1 was observed in 25% (35 of 141) of tumours, in a median of 5% of cells. Younger women were 14 times more likely to have ALDH1-positive tumours (P<0.01, OR 14.4, 95% CI 4.34-48.09). The ALDH1 correlated independently with ER negativity (P=0.01, OR 0.33, 95% CI 0.15-0.77). There was no correlation with disease recurrence or breast cancer-related deaths.
  
  
  CONCLUSIONS
  In younger women, ALDH1 was more highly expressed, and it correlated with ER negativity. It, however, did not predict survival in this study.
authors.affiliation: Department of General Surgery, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 308433, Singapore. Ern_Yu_Tan@ttsh.com.sg
authors.forename: E Y
authors.initials: EY
authors.lastname: Tan
authors.forename: A A
authors.initials: AA
authors.lastname: Thike
authors.forename: P H
authors.initials: PH
authors.lastname: Tan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000080924:Aldehyde Dehydrogenase 1 Family; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000201:enzymology* / Q000401:mortality; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D014411:Neoplastic Stem Cells / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism*; D050697:Retinal Dehydrogenase / Q000378:metabolism*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D007527:Isoenzymes; D011960:Receptors, Estrogen; D000080924:Aldehyde Dehydrogenase 1 Family; C510223:ALDH1A1 protein, human; D050697:Retinal Dehydrogenase