Dense Collagen-I Matrices Enhance Pro-Tumorigenic Estrogen-Prolactin Crosstalk in MCF-7 and T47D Breast Cancer Cells
Figure 4
High density/ stiff collagen matrices enhance E2 and PRL induced cell growth, and inhibit apoptosis in T47D cells.
a) T47D cells were cultured in LD or HD collagen and treated ± 1nM E2, ± 4nM PRL for 7d. Cells were removed from gels and counted via hemocytometer. n = 4. b) T47D cells were cultured in LD or HD collagen and treated ± 1nM E2, ± 4nM PRL for 72h and lysates were immunoblotted with the indicated antibodies. c) T47D cells were cultured as in (a), and treated ± 4-OHT 1h prior to hormone treatments and quantitation of cell number. n = 4. d,e,f,g) T47D cells were cultured as in (b), fixed and stained for DAPI and Ki-67 (d,e) or cleaved caspase 3 (f,g), and quantified as described in the Materials and Methods. n = 3. Representative images of DAPI/ Ki67 are shown in (e) and DAPI/ cleaved caspase 3 are shown in (g). Different letters represent significant differences (p<0.05) among treatments within each matrix condition (a,d,f) (LD, lower case; HD, upper case) or inhibitor treatments (c) (vehicle, lower case; 4-OHT, upper case). Asterisks indicate significant differences between the same treatments in different densities, *p<0.05, **p<0.01.