title: Mucosal alpha-papillomaviruses are not associated with esophageal squamous cell carcinomas: Lack of mechanistic evidence from South Africa, China and Iran and from a world-wide meta-analysis.
abstract: Epidemiological and mechanistic evidence on the causative role of human papillomaviruses (HPV) in esophageal squamous cell carcinoma (ESCC) is unclear. We retrieved alcohol- and formalin-fixed paraffin-embedded ESCC tissues from 133 patients seropositive for antibodies against HPV early proteins, from high-incidence ESCC regions: South Africa, China and Iran. With rigorous care to prevent nucleic acid contamination, we analyzed these tissues for the presence of 51 mucosotropic human alpha-papillomaviruses by two sensitive, broad-spectrum genotyping methods, and for the markers of HPV-transformed phenotype: (i) HPV16/18 viral loads by quantitative real-time PCR, (ii) type-specific viral mRNA by E6*I/E6 full-length RT-PCR assays and (iii) expression of cellular protein p16(INK4a). Of 118 analyzable ESCC tissues, 10 (8%) were positive for DNA of HPV types: 16 (4 tumors); 33, 35, 45 (1 tumor each); 11 (2 tumors) and 16, 70 double infection (1 tumor). Inconsistent HPV DNA+ findings by two genotyping methods and negativity in qPCR indicated very low viral loads. A single HPV16 DNA+ tumor additionally harbored HPV16 E6*I mRNA but was p16(INK4a) negative (HPV16 E1 seropositive patient). Another HPV16 DNA+ tumor from an HPV16 E6 seropositive patient showed p16(INK4a) upregulation but no HPV16 mRNA. In the tumor tissues of these serologically preselected ESCC patients, we did not find consistent presence of HPV DNA, HPV mRNA or p16(INK4a) upregulation. These results were supported by a meta-analysis of 14 other similar studies regarding HPV-transformation of ESCC. Our study does not support the etiological role of the 51 analyzed mucosotropic HPV types in the ESCC carcinogenesis.
authors.affiliation: Division of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.|Obstetrics & Gynecology, David Geffen School of Medicine at UCLA, Los Angeles, CA.
authors.forename: Gordana
authors.initials: G
authors.lastname: Halec
authors.affiliation: Division of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Schmitt
authors.affiliation: Cancer Council NSW, Cancer Research Division, Sydney, New South Wales, Australia.
authors.forename: Sam
authors.initials: S
authors.lastname: Egger
authors.affiliation: Division of Cancer Epidemiology and Genetics, US National Cancer Institute, Bethesda, MD.
authors.forename: Christian C
authors.initials: CC
authors.lastname: Abnet
authors.affiliation: National Health Laboratory Service, NHLS/MRC Cancer Epidemiology Research Group, Johannesburg, South Africa.
authors.forename: Chantal
authors.initials: C
authors.lastname: Babb
authors.affiliation: Division of Cancer Epidemiology and Genetics, US National Cancer Institute, Bethesda, MD.
authors.forename: Sanford M
authors.initials: SM
authors.lastname: Dawsey
authors.affiliation: Institute of Pathology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Christa
authors.initials: C
authors.lastname: Flechtenmacher
authors.affiliation: Infections and Cancer Biology Group, International Agency for Research on Cancer, Lyon, France.
authors.forename: Tarik
authors.initials: T
authors.lastname: Gheit
authors.affiliation: Department of Anatomical Pathology, National Health Laboratory Service, Johannesburg, South Africa.|Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Martin
authors.initials: M
authors.lastname: Hale
authors.affiliation: Division of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Dana
authors.initials: D
authors.lastname: Holzinger
authors.affiliation: Digestive Disease Research Center, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Malekzadeh
authors.affiliation: Division of Cancer Epidemiology and Genetics, US National Cancer Institute, Bethesda, MD.
authors.forename: Philip R
authors.initials: PR
authors.lastname: Taylor
authors.affiliation: Infections and Cancer Biology Group, International Agency for Research on Cancer, Lyon, France.
authors.forename: Massimo
authors.initials: M
authors.lastname: Tommasino
authors.affiliation: National Health Laboratory Service, NHLS/MRC Cancer Epidemiology Research Group, Johannesburg, South Africa.|Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: Margaret I
authors.initials: MI
authors.lastname: Urban
authors.affiliation: Division of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Tim
authors.initials: T
authors.lastname: Waterboer
authors.affiliation: Division of Molecular Diagnostics of Oncogenic Infections, Research Program Infection, Inflammation and Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Pawlita
authors.affiliation: Cancer Council NSW, Cancer Research Division, Sydney, New South Wales, Australia.|School of Public Health, University of Sydney, New South Wales, Australia.|School of Public Health and Community Medicine, University of New South Wales, Sydney, Australia.
authors.forename: Freddy
authors.initials: F
authors.lastname: Sitas
mesh_terms: D000368:Aged; D063646:Carcinogenesis / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000235:genetics / Q000821:virology*; D002681:China; D004938:Esophageal Neoplasms / Q000453:epidemiology / Q000235:genetics / Q000821:virology*; D000077277:Esophageal Squamous Cell Carcinoma; D005260:Female; D005838:Genotype; D052162:Human papillomavirus 16 / Q000235:genetics / Q000472:pathogenicity*; D052161:Human papillomavirus 18 / Q000235:genetics / Q000472:pathogenicity*; D006801:Humans; D007492:Iran; D008297:Male; D008875:Middle Aged; D009856:Oncogene Proteins, Viral / Q000235:genetics; D012097:Repressor Proteins / Q000235:genetics; D013019:South Africa
chemical_list: C068651:E6 protein, Human papillomavirus type 16; D009856:Oncogene Proteins, Viral; D012097:Repressor Proteins
keywords: HPV RNA; HPV-transformed phenotype; esophageal cancer; human papillomavirus; meta-analysis; p16INK4; serology