1. ¹Laboratory of Investigative Dermatology, Rockefeller University, New York, New York, USA
2. ²Department of Pathology, Weill Medical College of Cornell, New York, New York, USA
3. ³Laboratory of Statistical Genetics, Rockefeller University, New York, New York, USA
4. ⁴Ronald O. Perelman Department of Dermatology, New York University, New York, New York, USA
5. ⁵Department of Genetics, Washington University School of Medicine, St Louis, Missouri, USA
6. ⁶Section of Mohs Micrographic and Dermatologic Surgery, Department of Dermatology, Weill Medical College of Cornell, New York, New York, USA

Correspondence: Dr John A. Carucci, Section of Mohs Micrographic and Dermatologic Surgery, Department of Dermatology, Weill Medical College of Cornell, 525 East 68th Street, Starr 326, New York, New York 10021, USA. E-mail: JAC2015@med.cornell.edu

Received 20 July 2005; Revised 3 November 2005; Accepted 16 November 2005; Published online 9 February 2006.

Abstract

Using high-density oligonucleotide arrays, we measured expression of >12,000 genes in surgical excisions of invasive human squamous cell carcinomas (SCCs) versus site-matched control skin. This analysis defined >1,900 genes with altered expression in SCCs that were statistically different from controls. As SCCs are composed of epithelial cells, which are both hyperplastic and invasive, we sought to define gene sets associated with these biologic processes by comparing gene expression to psoriasis vulgaris, which is a condition of benign keratinocyte hyperplasia without invasiveness or pre-malignant potential. Through this analysis, we found genes that were commonly upregulated in both conditions and unique genes with increased expression in SCCs. Differential gene regulation in these two conditions was confirmed by real-time reverse transcription-PCR and immunohistochemistry. We found that benign hyperplasia is associated with upregulation of genes including DEFB4 (defensin B4), SERPINB3 (serine proteinase inhibitor, member 3), STAT1 (signal transducer and activator of transcription 1), K16 (keratin 16), CEACAMs (carcinoembryonic antigen-related cell adhesion molecules), and WNT 5A (wingless-type MMTV integration site family, member 5A). WNT receptor frizzled homolog 6 (FZD6) and prostaglandin-metabolizing enzyme hydroxyprostaglandin dehydrogenase were increased in SCC alone. Growth factor pleiotrophin (PTN) was expressed at higher levels in non-tumor-bearing skin adjacent to excised SCC. SCC was further characterized by upregulation of matrix metalloproteinases 1, 10, and 13, cathepsin L2, cystatin E/M as well as STAT3 and microseminoprotein, beta (MSMB), and downregulation of inducible nitric oxide synthase, granzyme B, CD8, and CD83. The current study defines a unique gene expression signature for cutaneous SCC in humans and suggests potential roles for WNT, FZD, and PTN in the pathogenesis of SCC.