12 research outputs found
CCR2-V64I polymorphism is associated with increased risk of cervical cancer but not with HPV infection or pre-cancerous lesions in African women
<p>Abstract</p> <p>Background</p> <p>Cervical cancer, caused by specific oncogenic types of human papillomavirus (HPV), is the second most common cancer in women worldwide. A large number of young sexually active women get infected by HPV but only a small fraction of them have persistent infection and develop cervical cancer pointing to co- factors including host genetics that might play a role in outcome of the HPV infection. This study investigated the role of <it>CCR2-V64I </it>polymorphism in cervical cancer, pre-cancers and HPV infection in South African women resident in Western Cape. <it>CCR2-V64I </it>polymorphism has been previously reported to influence the progression to cervical cancer in some populations and has also been associated with decreased progression from HIV infection to AIDS.</p> <p>Methods</p> <p>Genotyping for <it>CCR2-V64I </it>was done by PCR-SSP in a case-control study of 446 women (106 black African and 340 mixed-ancestry) with histologically confirmed invasive cervical cancer and 1432 controls (322 black African and 1110 mixed-ancestry) group-matched (1:3) by age, ethnicity and domicile status. In the control women HPV was detected using the Digene Hybrid Capture II test and cervical disease was detected by cervical cytology.</p> <p>Results</p> <p>The <it>CCR2-64I </it>variant was significantly associated with cervical cancer when cases were compared to the control group (P = 0.001). Further analysis comparing selected groups within the controls showed that individuals with abnormal cytology and high grade squamous intraepitleial neoplasia (HSIL) did not have this association when compared to women with normal cytology. HPV infection also showed no association with <it>CCR2-64I </it>variant. Comparing SIL positive controls with the cases showed a significant association of <it>CCR2-64I </it>variant (P = 0.001) with cervical cancer.</p> <p>Conclusions</p> <p>This is the first study of the role of <it>CCR2-V64I </it>polymorphism in cervical cancer in an African population. Our results show that <it>CCR2-64I </it>variant is associated with the risk of cervical cancer but does not affect the susceptibility to HPV infection or HSIL in South African women of black and mixed-ancestry origin. This result implies that the role of CCR2 is important in invasive cancer of the cervix but not in HPV infection or in the development of pre-cancers.</p
Human Papillomavirus E7 oncoprotein increases production of the anti-inflammatory IL-18 binding protein (IL-18BP) in keratinocytes
Human papillomavirus can successfully evade the host immune response to establish a persistent infection. We show here that expression of the E7 oncoprotein in primary human keratinocytes results in increased production of IL-18 binding protein (IL-18BP). This anti-inflammatory protein is a natural antagonist of IL-18 and is necessary for skin homeostasis. We map increased IL-18BP production to the CR3 region of E7 and demonstrate that this ability is shared amongst E7 proteins from different HPV types. Furthermore, mutagenesis shows that increased IL-18BP production is mediated by a gamma activated sequence (GAS) in the IL-18BP promoter. Importantly, the increased IL-18BP levels seen in E7 expressing keratinocytes are capable of diminishing IL-18 mediated CD4 lymphocyte activation. This study provides the first evidence for a virus protein that targets IL-18BP and further validates E7 as a key component of the HPV immune evasion armor. Importance: Infection with human papillomavirus is a leading cause of morbidity and mortality worldwide. This study demonstrates that the E7 protein increases production of the anti-inflammatory IL-18BP, a major regulator of epithelial homeostasis. A number of E7 proteins can increase IL-18BP production and a region within the CR3 of E7 is necessary for mediating the increase. A consequence of increased IL-18BP production is a reduction in CD4 positive lymphocyte activation in response to IL-18 co-stimulation. These findings may shed light on the immune evasion abilities of HPV
Reduced expression of chemokine (C-C motif) ligand-2 (CCL2) in ovarian adenocarcinoma
Chemokine (C-C motif) ligand-2 (CCL2) is a chemoattractant and activator of macrophages and is a key determinant of the macrophage infiltrate into tumours. We demonstrate here that CCL2 is expressed in normal human ovarian surface epithelium ( HOSE) cells and is silenced in most ovarian cancer cell lines, and silenced or downregulated in the majority of primary ovarian adenocarcinomas. Analysis of the CCL2 locus at 17q11.2-q12 showed loss of heterozygosity (LOH) in 70% of primary tumours, and this was significantly more common in tumours of advanced stage or grade. However, we did not detect any mutations in the CCL2 coding sequence in 94 primary ovarian adenocarcinomas. These data support the hypothesis that CCL2 may play a role in the pathobiology of ovarian cancers, but additional studies will be required to evaluate this possibility