Promoter Hypermethylation Analysis of Host Genes in Cervical Cancer Patients With and Without Human Immunodeficiency Virus in Botswana

Abstract

Background: Epidemics of human immunodeficiency virus (HIV) and cervical cancer are interconnected. DNA hypermethylation of host genes' promoter in cervical lesions has also been recognized as a contributor to cervical cancer progression.Methods: For this purpose we analyzed promoter methylation of four tumor suppressor genes (RARB, CADM1, DAPK1 and PAX1) and explored their possible association with cervical cancer in Botswana among women of known HIV status. Overall, 228 cervical specimens (128 cervical cancers and 100 non-cancer subjects) were used. Yates-corrected chi-square test and Fisher's exact test were used to explore the association of promoter methylation for each host gene and cancer status. Subsequently, a logistic regression analysis was performed to find which factors, HIV status, high risk-HPV genotypes, patient's age and promoter methylation, were associated with the following dependent variables: cancer status, cervical cancer stage and promoter methylation rate.Results: In patients with cervical cancer the rate of promoter methylation observed was greater than 64% in all the genes studied. Analysis also showed a higher risk of cervical cancer according to the increased number of methylated promoter genes (OR = 6.20; 95% CI: 3.66–10.51; P < 0.001). RARB methylation showed the strongest association with cervical cancer compared to other genes (OR = 15.25; 95% CI: 6.06–40.0; P < 0.001). Cervical cancer and promoter methylation of RARB and DAPK1 genes were associated with increasing age (OR = 1.12; 95% CI: 1.01-1.26; P = 0.037 and OR = 1.05; 95% CI: 1.00-1.10; P = 0.040). The presence of epigenetic changes at those genes appeared to be independent of HIV status among subjects with cervical cancer. Moreover, we found that cervical cancer stage was influenced by RARB (χ2= 7.32; P = 0.002) and CADM1 (χ2=12.68; P = 0.013) hypermethylation, and HIV status (χ2= 19.93; P = 0.001).Conclusion: This study confirms the association between invasive cervical cancer and promoter gene methylation of tumor suppressing genes at the site of cancer. HIV infection did not show any association to methylation changes in this group of cervical cancer patients from Botswana. Further studies are needed to better understand the role of HIV in methylation of host genes among cancer subjects leading to cervical cancer progression.

Digital Loop-Mediated Isothermal Amplification-Based Absolute Methylation Quantification Revealed Hypermethylated DAPK1 in Cervical Cancer Patients

“…Similar to the conventional HpaII-edited LAMP assay, high methylation levels were detected in HeLa cells. However, low methylation levels of DAPK1 were found in L-02 cells (6.42%) by HEADLAMP, which is consistent with previous literature reports of low levels of methylated DAPK1 in normal tissues. − This result demonstrated the advantage of HEADLAMP in discovering trace methylated genes.…”

Increased Gene Expression of C1orf74 Is Associated with Poor Prognosis in Cervical Cancer

“…Epigenetic regulation of gene expression through DNA methylation and post-translational modifications of histones at specific loci can result in uncontrolled cell proliferation and cervical carcinogenesis [39]. CpG islands are usually present at 5' promoter regions of many genes [40].…”

Deciphering DNA Methylation in HIV Infection

“…Methylation levels of the tumour suppressor EPB41L3 were significantly higher in HIV seropositive women with moderate grade neoplasia compared to HIV seronegative women ( 123 ). Methylation levels of microRNA-124–2 (miR-124–2), was significantly associated with HIV positive women with low, moderate and severe grade neoplasia compared to HIV negative women ( 124 ); however, no association was found between the methylation content of the tumour suppressor genes CADM1, MAL RARB, DAPK1 and PAX1 in HIV ( 124 , 125 ). The methylation of ASCL1, LHX8 and ST6GALNAC5 was significantly higher in HIV seropositive women with low to moderate grade neoplasia than HIV seronegative women.…”

“…With only a few studies evaluating the influence of HIV on the methylation of specific host genes, further examination is essential ( 26 , 38 , 41 , 107 , 117 , 123 , 125 , 126 ). Henceforth, we discuss potential host genes whose methylation status should be investigated with regard to HIV.…”