Fig 1.
Invasive ductal carcinoma (IDC) on chip.
(A) Microanatomical replication of IDC-on-chip. Epithelial cancer cells at the lining of the lumen structure formed through collagen gel. (B) 3D reconstruction of MCF-7 lumen structure in IDC-on-chip platform and cross-sectional images. Magenta stains are plasma membrane and blue are nuclei. (C) E-cadherin (E-cad, green) immunostaining of MCF-7 duct with nuclei (blue). Scale bars indicate 100μm.
Fig 2.
Invasion assay of three subtype-specific breast cancer cell lines in IDC-on-chip.
(A) Time-lapse micrographs of MCF-7, MDA-MB-231 and SUM-159PT ducts in IDC-on-chip at day 1, 3 and 6. Scale bars indicate 300 μm. (B) Quantification of local invasion on DAY1 and DAY3. (C) Quantification of local invasion length. MCF-7; MDA231, MDA-MB-231; 159PT, SUM-159PT; Bar; mean ± standard error. N.S; p>0.05, *; p < 0.05, and **; p < 0.01 (Student t-test).
Fig 3.
Invasion characteristics of SUM-159PT in IDC-on-chip.
(A) Bright field image of SUM-159PT cells in IDC-on-chip at day 3. Scale bar is 300 μm. (B) Confocal micrograph of SUM-159PT at day 3, cells showed characteristics of multicellular collective migration in the protrusion. Cell nuclei along a protrusion are noted with white arrows. Nuclei (blue) and plasma membrane (magenta). (C and D) The duct of SUM-159PT showed regions of matrix collapse, which are thought to be associated with matrix degradation (noted with arrows), it was observed from day 5 to day 7.
Fig 4.
Histology and Immunohistology of SUM-159PT cells in IDC-on-chip.
(A) Structure and cell morphology at the duct in IDC-on-chip. Histological staining of the cells in the duct was performed with Haematoxylin and Eosin (H&E) at day 3 of culture. (B) Evaluation of cell proliferation using BrdU assay. (C) Expression of N-cadherin at the protrusions. Nuclei (blue) and N-cadherin (red). N-cadherin is a cell-cell adhesion marker important for migratory and invasive behavior of tumoral cells.
Fig 5.
Comparison of the expression of cell surface markers CD44, and CD24 between 2D culture and IDC-on-chip for the three subtype-specific breast cancer cell lines.