title: Breast cancer-associated fibroblasts induce epithelial-to-mesenchymal transition in breast cancer cells.
abstract: Cancer-associated fibroblasts (CAFs) play a role in tumour initiation and progression, possibly by inducing epithelial-to-mesenchymal transition (EMT), a series of cellular changes that is known to underlie the process of metastasis. The aim of this study was to determine whether CAFs and surrounding normal breast fibroblasts (NBFs) are able to induce EMT markers and functional changes in breast epithelial cancer cells. Matched pairs of CAFs and NBFs were established from fresh human breast cancer specimens and characterised by assessment of CXCL12 levels, α-smooth muscle actin (α-SMA) levels and response to doxorubicin. The fibroblasts were then co-cultured with MCF7 cells. Vimentin and E-cadherin expressions were determined in co-cultured MCF7 cells by immunofluorescence and confocal microscopy as well as by western blotting and quantitative PCR. Co-cultured MCF7 cells were also assessed functionally by invasion assay. CAFs secreted higher levels of CXCL12 and expressed higher levels of α-SMA compared with NBFs. CAFs were also less sensitive to doxorubicin as evidenced by less H2AX phosphorylation and reduced apoptosis on flow cytometric analysis of Annexin V compared with NBFs. When co-cultured with MCF7 cells, there was greater vimentin and less E-cadherin expression as well as greater invasiveness in MCF7 cells co-cultured with CAFs compared with those co-cultured with NBFs. CAFs have the ability to induce a greater degree of EMT in MCF7 cell lines, indicating that CAFs contribute to a more malignant breast cancer phenotype and their role in influencing therapy resistance should therefore be considered when treating breast cancer.
authors.affiliation: Hormones and Cancer Group, Kolling Institute of Medical Research, Royal North Shore Hospital, Sydney, New South Wales, Australia. patsy.soon@sydney.edu.au
authors.forename: Patsy S H
authors.initials: PS
authors.lastname: Soon
authors.forename: Edward
authors.initials: E
authors.lastname: Kim
authors.forename: Cindy K
authors.initials: CK
authors.lastname: Pon
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Gill
authors.forename: Katrina
authors.initials: K
authors.lastname: Moore
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Spillane
authors.forename: Diana E
authors.initials: DE
authors.lastname: Benn
authors.forename: Robert C
authors.initials: RC
authors.lastname: Baxter
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D017209:Apoptosis; D015153:Blotting, Western; D001940:Breast / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D018920:Coculture Techniques; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004317:Doxorubicin / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm; D004797:Enzyme-Linked Immunosorbent Assay; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017154:Stromal Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D014746:Vimentin / Q000235:genetics / Q000378:metabolism
chemical_list: D000903:Antibiotics, Antineoplastic; D015820:Cadherins; D017077:Culture Media, Conditioned; D012333:RNA, Messenger; D014746:Vimentin; D004317:Doxorubicin