title: Quantitative analysis of IL-10 and IFN-gamma mRNA levels in normal cervix and human papillomavirus type 16 associated cervical precancer.
abstract: Human papillomavirus type 16 is a major factor in cervical carcinogenesis. Inappropriate cytokine synthesis may direct the local immune response away from a type-1 (cellular) pattern and may subsequently contribute to the development and progression of precancer. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) using a competitive mimic was carried out to determine type-1 (interferon gamma (IFN-gamma)) and type-2 (interleukin-10 (IL-10)) cytokine mRNA levels in whole cervical specimens (without microdissection) from seven normal and nine HPV-16 positive CIN formalin-fixed paraffin-embedded tissues. Microdissection was used to measure separately the epithelial and sub-epithelial levels of IFN-gamma and IL-10 mRNAs in 11 specimens of normal cervix and 25 HPV-16 positive CIN (nine CIN 1, seven CIN 2 and nine CIN 3). IFN-gamma mRNA was lower in CIN than normal (p=0.04). IL-10 mRNA level in CIN was significantly higher (p=0.005) than in normal cervix (before microdissection). Epithelial IFN-gamma mRNA showed a significant decrease in all grades of CIN (median=3.58) compared with normal (7.74) (p<0.05), but there was no significant difference between the grades. A significant decrease in sub-epithelial IFN-gamma mRNA was found in CIN 1(9.81), CIN 2 (3.82) and CIN 3 (4.62) compared with normal cervix (27.35) (p<0.05). Also, sub-epithelial IFN-gamma mRNA was significantly lower in CIN 2 and CIN 3 than in CIN 1 (p=0.005 and 0.0005, respectively). IL-10 was detected in the epithelium of only one of 11 normal and one of 25 CIN, but sub-epithelial IL-10 was significantly higher in CIN 2 (0.08) and CIN 3 (0.26) than in normal (0.00) (p=0.036 and 0.0032, respectively). There was no significant difference in the sub-epithelial level of IL-10 between normal and CIN 1 (0.00) (p=0.96). Our results suggest that reduced epithelial and sub-epithelial IFN-gamma, as well as increased sub-epithelial IL-10 synthesis may play a role in the development and progression of HPV-16 associated cervical precancer.
authors.affiliation: Division of Pathology, Queens Medical Centre, University Hospital, Nottingham, UK. amiraelsherif@hotmail.com
authors.forename: A M
authors.initials: AM
authors.lastname: El-Sherif
authors.forename: R
authors.initials: R
authors.lastname: Seth
authors.forename: P J
authors.initials: PJ
authors.lastname: Tighe
authors.forename: D
authors.initials: D
authors.lastname: Jenkins
mesh_terms: D002584:Cervix Uteri / Q000276:immunology*; D018450:Disease Progression; D004848:Epithelium / Q000276:immunology; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000235:genetics; D016753:Interleukin-10 / Q000096:biosynthesis* / Q000235:genetics; D027383:Papillomaviridae / Q000145:classification / Q000302:isolation & purification*; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D002583:Uterine Cervical Neoplasms / Q000276:immunology* / Q000473:pathology / Q000821:virology; D002578:Uterine Cervical Dysplasia / Q000276:immunology* / Q000473:pathology / Q000821:virology
chemical_list: D012333:RNA, Messenger; D012334:RNA, Neoplasm; D016753:Interleukin-10; D007371:Interferon-gamma