Figure 1.

Breast epithelial and carcinoma cells preferentially cluster upon matrix detachment. A, MCF10-A, SUM-159, and Hs578t cells (vector and β4-depleted) were detached and allowed to cluster spontaneously or treated with either 2 mm EDTA or 0. 5% methylcellulose to generate single-cell suspensions. Photomicrographs were taken 2 h post-detachment. Scale bars = 10 microns. B, quantification of MCF10-A, SUM-159, and Hs578t clusters was performed by counting the total number of single and clustered cells, total number of clusters (defined as ≥ 3 cells). Six independent photos of each cell line and each condition were quantified. ***, p < 0.005. C, the β4 integrin subunit was depleted in Hs578t cells by CRISPR/Cas9 using two independent guide RNAs (β4-3 and β4-4). Depletion of β4 expression was verified by immunoblotting.