BRIEF REPORT Effects of cytokines on long control region transcriptional activity in high-risk cutaneous human papillomavirus types 5 and 8 Manuela Donalisio • Alice Poli • Andrea Civra • Santo Landolfo • David Lembo Received: 16 November 2009 / Accepted: 6 January 2010 / Published online: 25 February 2010 Ó Springer-Verlag 2010 Abstract Cytokines play an important role in the control of mucosal HPV transcription. However, there is little data available on cutaneous HPVs, which are associated with non-melanoma skin cancers. Here, we describe a cell-based assay exploiting HaCaT keratinocytes stably transfected with a reporter construct containing the long control region (LCR) regulatory sequence of gene transcription in HPV-5 and HPV-8. This novel assay has allowed the first sys- tematic analysis of the effects of cytokines on HPV-5 and HPV-8 LCR activity and provides a valuable tool for the search for cutaneous HPV-gene expression inhibitors. Human papillomaviruses (HPVs) are small double- stranded DNA viruses that cause a wide variety of hyper- proliferative lesions of the skin and other mucosae [16]. The mucosal HPVs are grouped into the genus Alphapap- illomavirus of the family Papillomaviridae, while the cutaneous types mostly belong to the genus Betapa- pillomavirus [9]. Infections with certain mucosal HPV types (e.g. HPV-16 and HPV-18) have a high risk of undergoing malignant transformation [31, 42]. In contrast, the role of the cutaneous HPV types in skin carcinogenesis is not yet fully understood. There has been increasing evidence demonstrating the association between some cutaneous HPV types (e.g. HPV-5 and HPV-8) and the development of non-melanoma skin cancers (NMSCs), which include basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) [8, 11, 15, 25, 33, 39]. The E6 and E7 oncogenes of high-risk mucosal HPV types, those that are consistently expressed in cervical cancer, play a key role during carcinogenesis, interfering with cell-cycle regulation and apoptosis [10, 24, 30, 42]. Although the mechanisms by which cutaneous E6 and E7 act as oncoproteins are poorly understood, several features support their active roles in skin lesions [1, 6, 7, 17, 18, 26, 28, 38, 41]. The development and progression of lesions associated with mucosal and cutaneous HPV depends on virus gene expression, intracellular control mechanisms and deficien- cies in the host’s immunosurveillance. In this context, an important role is played by the local release of arrays of cytokines by the keratinocytes and the mononuclear cells infiltrating the skin and the mucosae [2]. Indeed, besides their immunomodulatory activities, cytokines may also exert direct antiviral effects through the suppression of mucosotropic HPV-gene transcription [3, 21]. In a previous paper, we reported the systematic analysis of the effects of cytokines on early gene transcription of the mucosotropic HPV-16, employing a cell-based reporter assay [23]. Among the inhibitory cytokines, type-1 interferons, TGF- b, IL-14 and IL-13 exerted the greatest effects. As very little is known about the effect of cytokines on the tran- scription of the high-risk cutaneous HPV type, the aim of the present study was to assess the effects of a large array of cytokines on the long control region (LCR) transcrip- tional activity of cutaneous HPV. HPV-5 and HPV-8 were chosen for this investigation, as they represent beta geno- types that are involved in NMSC in EV. HPV-16 was included as the prototype of a mucosal high-risk genotype. M. Donalisio Á A. Poli Á A. Civra Á D. Lembo (&) Department of Clinical and Biological Sciences, S. Luigi Gonzaga Hospital, University of Turin, Regione Gonzole, 10, 10043 Orbassano, Turin, Italy e-mail: david.lembo@unito.it S. Landolfo Department of Public Health and Microbiology, University of Turin, 10126 Turin, Italy 123 Arch Virol (2010) 155:583–587 DOI 10.1007/s00705-010-0615-2