17-beta-estradiol affects nuclear image properties in MCF-10F human breast epithelial cells with tumorigenesis.
Treatment of the human breast epithelial cells MCF-10F with 17-beta-estradiol (E2) induces transformation and tumorigenesis. E2-transformed MCF-10F cells are known to exhibit progressive loss of ductulogenesis, and invasive and tumorigenic phenotypes. Although DNA amounts and chromatin supraorganization change in E2-transformed MCF cells, no comparative study has yet been undertaken in the resulting cells selected for aggressive invasiveness (C5) and tumor generation in a heterologous host. The aim of this study was thus to determine whether changes in Feulgen-DNA content and chromatin supraorganization are involved during E2-induced transformation and tumorigenesis of the MCF-10F cells. Image analysis was performed for nontransformed and E2-transformed MCF cells, highly invasive cells (C5), and for cell lines (C5-A6-T6 and C5-A8-T8) derived from tumors generated by injection of C5 cells in SCID mice. A decrease in Feulgen-DNA amounts and nuclear sizes induced by E2 treatment was accented with selection of the highly invasive tumorigenesis potential. However, in the tumor-derived cells a high variability in cellular phenotypes resulted inclusively in near-polyploidy. Significant changes in textural parameters, including nuclear entropy, indicated chromatin structural remodeling with advancing tumorigenesis. An increased variability in the degree of chromatin packing states in the E2-transformed MCF cells is followed by reduction in chromatin condensation and in contrast between condensed and noncondensed chromatin in the highly invasive C5 cells and tumor-derived cell lines. Studies on epigenetic mechanisms involving DNA methylation and/or the histone code would contribute to a better interpretation of the chromatin supraorganization changes reported herein.
Mello
Maria Luiza S
ML
Department of Cell Biology, Institute of Biology, UNICAMP, 13083-863 Campinas (SP), Brazil. mlsmello@unicamp.br
Russo
Patricia
P
Russo
Jose
J
Vidal
Benedicto C
BC
D001940:Breast / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D001943:Breast Neoplasms / Q000473:pathology*; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D004847:Epithelial Cells / Q000187:drug effects / Q000502:physiology; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006801:Humans; D009361:Neoplasm Invasiveness
D004958:Estradiol