Regulation of cell polarity during carcinogenic processes associated to HPV infections

MARINA BUGNON VALDANO, ANA LAURA CAVATORTA, FEDERICO MARZIALI, FLORENCIA FACCIUTO, ENRIQUE BOCCARDO, DANIELA GARDIOL

Valparaìso

Simposio; III Latin American Zebrafish Network (LAZEN) Symposium; 2014

Latin American Zebrafish Network (LAZEN)

Abstract Regulation of cell polarity proteins during the HPV-associated carcinogenesis Marina Bugnon Valdano1; Ana Laura Cavatorta1; Federico Marziali1; Florencia Facciuto1; Enrique Boccardo2; Daniela Gardiol1 1Área Virología, IBR/CONICET, Fac. Cs. Bioq. y Farmacéuticas, UNR, Argentina; 2Laboratorio de Oncovirología, ICB, USP, Brasil. mbugnonvaldano@yahoo.com.ar Human papillomaviruses (HPV) are classified as low or high risk types, depending on the associated clinical manifestations. Mucosotropic infection by high risk HPV is the key event in the development of cervical carcinoma. We are studying the interference of HPV oncoproteins with cellular proteins involved in cell polarity, whose loss is associated with tumor progression. RAFT organotypic cultures reproduce epithelial differentiation in vitro and closely mimic the HPV-host interaction. In the present work, we developed raft cultures expressing E6 and E7 HPV major oncoproteins. The morphological characteristics of the obtained tissues were examined and in the case of RAFTs expressing both oncoproteins such characteristics differed from those identified in normal epithelium. Hyper-proliferation was observed when both oncoproteins were co-expressed, effect that was not observed for low oncogenic risk HPV. E6 and E7 expression was confirmed by RT-PCR and, when possible, by Western blot (WB). Also, we analyzed the expression of cellular known polarity targets of HPV oncoproteins. We focused on DLG1, a cellular target of high risk HPV, whose expression is altered during malignant progressions and particularly in HPV-related tumors. Using rafts expressing E6 and E7 from high risk HPV, we evaluated the level and localization of DLG1, finding alterations in the expression patterns of this protein. In addition, we extended our analysis to other polarity cellular proteins. Altogether, we have analyzed the expression of polarity cellular targets of HPV, in a context that closely resembles in vivo infections. The implementation of Zebrafish model will be extremely useful to improve our studies on the regulation of cellular polarity proteins during malignant progression.