Regulation and characterization of the polarity of cells embedded in a reconstructed basement matrix using a three-dimensional micro-culture system.
Three cell lines, that is, the human breast cancer cell line (MCF-7) and the human mammary epithelial cell line (S-1) and its malignant form (T4-2) were embedded in a reconstituted basement membrane (Matrigel) that had 20-nL pyramid-shaped silicon microstructures. The proliferative behavior of the MCF-7 cells was dependent on the surrounding conditions (2-D, collagen gel, or Matrigel), whereas the respiratory activity of a single cell (F(c)) was almost identical under different culture conditions. The F(c) value changed with cellular polarity. The F(c) value for the S-1 cells was observed to decrease slightly, whereas that of the T4-2 cells increased 2 days after cultivation in the microstructures within the Matrigel. However, when the T4-2 cells were cultured in the presence of tyrphostin AG 1478 (T4-2 tyr) to inhibit epidermal growth factor (EGF) signaling, the F(c) value decreased slightly and remained almost constant for an additional 1 week; this was similar to the behavior of the S-1 cells. Further, fluorescence images showed that the T4-2 tyr cells formed polar structures that were similar to those formed by the S-1 cells whereas the T4-2 cells did not form such structures. These results indicate that cellular polarity can be assessed by measuring cellular respiratory activity.
Torisawa
Yu-Suke
YS
Graduate School of Environmental Studies, Tohoku University, Sendai 980-8579, Japan.
Nashimoto
Yuji
Y
Yasukawa
Tomoyuki
T
Shiku
Hitoshi
H
Matsue
Tomokazu
T
D001485:Basement Membrane / Q000502:physiology*; D001943:Breast Neoplasms / Q000378:metabolism / Q000648:ultrastructure; D018929:Cell Culture Techniques / Q000379:methods*; D016764:Cell Polarity / Q000502:physiology*; D004847:Epithelial Cells / Q000166:cytology / Q000502:physiology*; D005109:Extracellular Matrix / Q000502:physiology*; D009368:Neoplasm Transplantation; D014407:Tumor Cells, Cultured / Q000378:metabolism / Q000648:ultrastructure