[1] IUCS, Inst Invest & Formacao Avancada Ciencias & Tecnol, CESPU, Rua Cent Gandra 1317, P-4585116 Gandra, PRD, Portugal
[2] Inst Univ Ciencias Saude, Med & Oral Surg Dept, Gandra, Portugal
[3] Univ Porto, Inst Mol Pathol & Immunol, IPATIMUP, Rua Campo Alegre 823, P-4100 Oporto, Portugal
[4] Univ Porto, Inst Invest & Inovacao Saude, Rua Campo Alegre 823, P-4100 Oporto, Portugal
[5] Univ Porto, Fac Med, Rua Campo Alegre 823, P-4100 Oporto, Portugal
[6] Oporto Hosp Ctr, Hosp Santo Antonio, Dept Stomatol, Oporto, Portugal
[7] Univ Porto, Inst Biomed Sci Abel Salazar ICBAS, Mol Pathol & Immunol Dept, Rua Campo Alegre 823, P-4100 Oporto, Portugal
[8] Univ Porto, Ctr Interdisciplinar Invest Marinha & Ambintal CI, Rua Campo Alegre 823, P-4100 Oporto, Portugal
[9] Kings Coll London, WHO, Collaborating Ctr Oral Canc, Dept Oral Med, London, England