MCF-7 human mammary adenocarcinoma cells exhibit augmented responses to human insulin on a collagen IV surface

J Appl Toxicol. 2009 Aug;29(6):470-7. doi: 10.1002/jat.1428.


Human mammary cell lines are extensively used for preclinical safety assessment of insulin analogs. However, it is essentially unknown how mitogenic responses can be optimized in mammary cell-based systems. We developed an insulin mitogenicity assay in MCF-7 human mammary adenocarcinoma cells, under low serum (0.1% FCS) and phenol red-free conditions, with 3H thymidine incorporation as endpoint. Based on EC50 values determined from 10-fold dilution series, beta-estradiol was the most potent mitogen, followed by human IGF-1, human AspB10 insulin and native human insulin. AspB10 insulin was significantly more mitogenic than native insulin, validating the ability of the assay to identify hypermitogenic human insulin analogs. With MCF-7 cells on a collagen IV surface, the ranking of mitogens was maintained, but fold mitogenic responses and dynamic range and steepness of dose-response curves were increased. Also, PI3K pathway activation by insulin was enhanced on a collagen IV surface. This study provided the first determination and ranking of the mitogenic potencies of standard reference compounds in an optimized MCF-7 assay. The optimized MCF-7 assay described here is of relevance for in vitro toxicological testing and carcinogenicity safety assessment of new insulin compounds.

MeSH terms

  • Adenocarcinoma / metabolism*
  • Adenocarcinoma / pathology
  • Animals
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Cell Line, Tumor
  • Collagen Type IV / metabolism*
  • Collagen Type IV / pharmacology
  • Dose-Response Relationship, Drug
  • Estradiol / metabolism
  • Female
  • Humans
  • Hypoglycemic Agents / metabolism
  • Hypoglycemic Agents / pharmacology
  • Insulin / analogs & derivatives
  • Insulin / metabolism*
  • Insulin / pharmacology
  • Lethal Dose 50
  • Mice
  • Mitogens / metabolism
  • Mitosis
  • Reference Standards
  • Reproducibility of Results
  • Thymidine / metabolism


  • Collagen Type IV
  • Hypoglycemic Agents
  • Insulin
  • Mitogens
  • Estradiol
  • Thymidine