title: Co-culture of 3D tumor spheroids with fibroblasts as a model for epithelial-mesenchymal transition in vitro.
abstract: Epithelial-mesenchymal transition (EMT) acts as a facilitator of metastatic dissemination in the invasive margin of malignant tumors where active tumor-stromal crosstalks take place. Co-cultures of cancer cells with cancer-associated fibroblasts (CAFs) are often used as in vitro models of EMT. We established a tumor-fibroblast proximity co-culture using HT-29 tumor spheroids (TSs) with CCD-18 co fibroblasts. When co-cultured with TSs, CCD-18 co appeared activated, and proliferative activity as well as cell migration increased. Expression of fibronectin increased whereas laminin and type I collagen decreased in TSs co-cultured with fibroblasts compared to TSs alone, closely resembling the margin of in vivo xenograft tissue. Active TGFβ1 in culture media significantly increased in TS co-cultures but not in 2D co-cultures of cancer cells-fibroblasts, indicating that 3D context-associated factors from TSs may be crucial to crosstalks between cancer cells and fibroblasts. We also observed in TSs co-cultured with fibroblasts increased expression of α-SMA, EGFR and CTGF; reduced expression of membranous β-catenin and E-cadherin, together suggesting an EMT-like changes similar to a marginal region of xenograft tissue in vivo. Overall, our in vitro TS-fibroblast proximity co-culture mimics the EMT-state of the invasive margin of in vivo tumors in early metastasis.
authors.affiliation: Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea. Electronic address: j.sarah.k@gmail.com.
authors.forename: Sun-Ah
authors.initials: SA
authors.lastname: Kim
authors.affiliation: Department of Biochemistry, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea; Cancer Evolution Research Center, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea. Electronic address: leeek@catholic.ac.kr.
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Lee
authors.affiliation: Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea; Cancer Evolution Research Center, College of Medicine, The Catholic University of Korea, Seoul 137-701, Republic of Korea. Electronic address: hkuh@catholic.ac.kr.
authors.forename: Hyo-Jeong
authors.initials: HJ
authors.lastname: Kuh
mesh_terms: D000818:Animals; D002465:Cell Movement; D018920:Coculture Techniques; D019008:Drug Resistance, Neoplasm; D058750:Epithelial-Mesenchymal Transition; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000502:physiology*; D019073:HT29 Cells; D006801:Humans; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation; D018874:Spheroids, Cellular / Q000502:physiology*; D053773:Transforming Growth Factor beta1 / Q000502:physiology
chemical_list: D053773:Transforming Growth Factor beta1
keywords: 3D culture; Cancer-associated fibroblasts (CAFs); Colorectal cancer (CRC); Epithelial–mesenchymal transition (EMT); Proximity co-culture; Tumor spheroids (TS)