Microenvironment and Immunology Fibroblast-Derived Dermal Matrix Drives Development of AggressiveCutaneous SquamousCell Carcinoma in Patients with Recessive Dystrophic Epidermolysis Bullosa

Patients with the genetic skin blistering disease recessive dystrophic epidermolysis bullosa (RDEB) develop aggressive cutaneous squamous cell carcinoma (cSCC). Metastasis leading tomortality is greater in RDEB than in other patient groups with cSCC. Here we investigate the dermal component in RDEB using mRNA expression profiling to compare cultured fibroblasts isolated from individuals without cSCC and directly from tumor matrix in RDEB and non-RDEB samples. Although gene expression of RDEB normal skin fibroblasts resembled that of cancer-associated fibroblasts, RDEB cancer-associated fibroblasts exhibited a distinct and divergent gene expression profile, with a large proportion of the differentially expressed genes involved in matrix and cell adhesion. RDEB cancer-associated fibroblasts conferred increased adhesion and invasion to tumor and nontumor keratinocytes. Reduction of COL7A1, the defective gene in RDEB, in normal dermal fibroblasts led to increased type XII collagen, thrombospondin-1, andWnt-5A, while reexpression of wild type COL7A1 in RDEB fibroblasts decreased type XII collagen, thrombospondin-1, and Wnt-5A expression, reduced tumor cell invasion in organotypic culture, and restricted tumor growth in vivo. Overall, our findings show that matrix composition in patients with RDEB is a permissive environment for tumor development, and type VII collagen directly regulates the composition of matrix proteins secreted by dermal and cancer-associated fibroblasts. Cancer Res; 72(14); 3522–34. 2012 AACR. Introduction Recessive dystrophic epidermolysis bullosa (RDEB) is an inherited skin blistering disease caused exclusively by mutations in the gene-encoding type VII collagen, COL7A1 (1). Type VII collagen is the main component of anchoring fibrils, structures that support anchorage of the epidermis to the underlying dermis (2). The central dogma is that defective anchoring fibrils lead to skin fragility characterized by longterm wounds and healing with scarring, resulting in considerable disruption to dermal architecture (3). This devastating condition is further complicated by the development of numerous, aggressive cutaneous squamous cell carcinoma (cSCC) suggestive of a field effect. Tumors frequently metastasize, resulting in more than 80%mortality by age 50 (4). This rate of metastasis far exceeds other patient groups in which cSCC is also a major complication, such as organ transplant patients and patients with the hereditary disease xeroderma pigmentosum, the reasons for which remain unclear (5). Protocols for the early detection and aggressive management, including amputation, radiation therapy, and chemotherapy, have not been proven to increase survival in RDEB cSCC (6). Previous studies have failed to identify consistent differences between RDEB cSCC and cSCC from the general population or organ transplant recipients in spite of the different clinicopathologic behavior. In fact, in virtually all studies to date, RDEB cSCC exhibit similar characteristics to non-RDEB cSCC and a causative relationship with tumor progression has yet to be unequivocally identified (7–15). With few exceptions these studies have focused on tumor keratinocytes and have ignored the surrounding stroma. Cancer-associated fibroblasts are the main cell type present in tumor stroma andhave been shown to contribute toward cancer invasion (16), initiation, and progression via stromal–epithelial interactions (17–19) and can provide oncogenic signals such as fibroblast growth factors, Authors' Affiliations: Division of Cancer Research, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee; Department of Plastic Surgery, Ninewells Hospital and Medical School, Dundee, United Kingdom; Institute of Medical Biology, A Star, Singapore; Universidad Autonoma de Nuevo Leon, Monterrey, Mexico; St George Hospital, University of New South Wales, Sydney, New South Wales, Australia; Department of Dermatology, Keck School of Medicine, University of Southern California, Los Angeles, California; Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee; and St John's Institute of Dermatology, King's College London (Guy's Campus), London, United Kingdom Note: Supplementary data for this article are available at Cancer Research Online (http://cancerres.aacrjournals.org/). Corresponding Author: Andrew P. South, Division of Cancer Research, Clinical Research Centre, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK. Phone: 44-1382-496432; Fax: 44-1382-436892; E-mail: [email protected] doi: 10.1158/0008-5472.CAN-11-2996 2012 American Association for Cancer Research. Cancer Research Cancer Res; 72(14) July 15, 2012 3522 on September 13, 2017. © 2012 American Association for Cancer Research. cancerres.aacrjournals.org Downloaded from Published OnlineFirst May 7, 2012; DOI: 10.1158/0008-5472.CAN-11-2996