Distribution of aldehyde dehydrogenase 1-positive stem cells in benign mammary tissue from women with and without breast cancer

Histopathology. 2012 Mar;60(4):617-33. doi: 10.1111/j.1365-2559.2011.04109.x. Epub 2012 Jan 19.


Aims: Aldehyde dehydrogenase 1 (ALDH1) in female breast tissue has been linked to stem cells, but little is known about the benign cellular organization in situ. We investigated the distribution of ALDH1-immunoreactive (ALDH1+) cells in histomorphologically benign breast tissue from 28 women with or without breast cancer.

Methods and results: ALDH1+ cells were detected in benign tissue of women aged 20-72 years, located most commonly at the luminal and intermediate ductular levels and in the stroma. ALDH1+ cell populations and Ki67+ cell populations were present in separate ductules, both cell types rarely showing epithelial differentiation. ALDH1+ cells were non-reactive to Ki67 and oestrogen receptor. Stromal round/oval ALDH1+ non-leukocyte cells in both age groups expressed contractile protein. There was a lower concentration of luminal and intermediate ductular ALDH1+ cells in postmenopausal women than in premenopausal women, and in cancer patients than in non-cancer patients, and a higher concentration in women receiving exogenous hormones.

Conclusions: This study provides further evidence for the stem cell character of ALDH1+ cells, here in benign breast tissue of cancer and non-cancer patients throughout non-lactating adult life, and contributes evidence of benign stromal ALDH1+ cells. The distribution of ductular ALDH1+ stem cells appears to be influenced by hormonal status.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aldehyde Dehydrogenase 1 Family
  • Breast Neoplasms / enzymology*
  • Breast Neoplasms / pathology
  • Female
  • Humans
  • Isoenzymes / metabolism*
  • Mammary Glands, Human / enzymology*
  • Mammary Glands, Human / pathology
  • Middle Aged
  • Retinal Dehydrogenase / metabolism*
  • Stem Cells / enzymology*


  • Isoenzymes
  • Aldehyde Dehydrogenase 1 Family
  • ALDH1A1 protein, human
  • Retinal Dehydrogenase