Differentiation of breast cancer cells in vitro is promoted by the concurrent influence of myoepithelial cells and relaxin.
Our previous studies showed that relaxin promotes differentiation of MCF-7 breast adenocarcinoma cells. In the current investigation, we aimed to elucidate whether the effect of the hormone is potentiated when MCF-7 cells are grown together with myoepithelial cells, thus creating a microenvironment reminiscent of the organised tissue architecture of the mammary parenchyma in vivo. The findings obtained reveal that most MCF-7 cells cultured alone have an undifferentiated, blast-like phenotype, only a minority showing a more differentiated phenotype with more organelles and rudimentary intercellular junctions. When co-cultured with myoepithelial cells more MCF-7 cells acquire ultrastructural features consistent with a more differentiated phenotype, such as a rich organellular complement, apical microvilli and intercellular junctions. When relaxin was added to the co-cultures, the ultrastructural signs of differentiation could be observed in even more MCF-7 cells and became more pronounced than in the absence of the hormone, judged by the appearance of a clear-cut polarisation of cytoplasmic organelles, an almost continuous coat of apical microvilli and numerous intracellular pseudolumina.
Bani
D
D
Department of Human Anatomy and Histology, University of Florence, Italy.
Riva
A
A
Bigazzi
M
M
Bani Sacchi
T
T
D000230:Adenocarcinoma / Q000188:drug therapy / Q000473:pathology* / Q000648:ultrastructure; D001940:Breast / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000648:ultrastructure; D002454:Cell Differentiation / Q000187:drug effects; D003470:Culture Media; D004847:Epithelial Cells; D004848:Epithelium / Q000502:physiology; D006801:Humans; D012065:Relaxin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects
D003470:Culture Media; D012065:Relaxin