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1.  DNA Methylation Profile at the DNMT3L Promoter 
Epigenetic events play a prominent role during cancer development. This is evident from the fact that almost all cancer types show aberrant DNA methylation. These abnormal DNA methylation levels are not restricted to just a few genes but affect the whole genome. Previous studies have shown genome-wide DNA hypomethylation and gene-specific hypermethylation to be a hallmark of most cancers. Molecules like DNA methyltransferase act as effectors of epigenetic reprogramming. In the present study we have examined the possibility that the reprogramming genes themselves undergo epigenetic modifications reflecting their changed transcriptional status during cancer development. Comparison of DNA methylation status between the normal and cervical cancer samples was carried out at the promoters of a few reprogramming molecules. Our study revealed statistically significant DNA methylation differences within the promoter of DNMT3L. A regulator of de novo DNA methyltransferases DNMT3A and DNMT3B, DNMT3L promoter was found to have lost DNA methylation to varying levels in 14 out of 15 cancer cervix samples analysed. The present study highlights the importance of DNA methylation profile at DNMT3L promoter not only as a promising biomarker for cervical cancer, which is the second most common cancer among women worldwide, but also provides insight into the possible role of DNMT3L in cancer development.
PMCID: PMC2080824  PMID: 17965599
DNMT3L; DNA methylation; cervical cancer; biomarker; nuclear reprogramming
2.  Prevalence and distribution of high-risk human papilloma virus (HPV) types in invasive squamous cell carcinoma of the cervix and in normal women in Andhra Pradesh, India 
Despite the high incidence of cervical cancer reported from India, large scale population based studies on the HPV prevalence and genotype distribution are very few from this region. In view of the clinical trials for HPV vaccine taking place in India, it is of utmost importance to understand the prevalence of HPV genotypes in various geographical regions of India. We investigated the genotype distribution of high-risk HPV types in squamous cell carcinomas and the prevalence of high-risk HPV in cervicovaginal samples in the southern state of Andhra Pradesh (AP), India.
HPV genotyping was done in cervical cancer specimens (n = 41) obtained from women attending a regional cancer hospital in Hyderabad. HPV-DNA testing was also done in cervicovaginal samples (n = 185) collected from women enrolled in the cervical cancer screening pilot study conducted in the rural community, of Medchal Mandal, twenty kilometers away from Hyderabad.
High-risk HPV types were found in 87.8% (n = 36/41) of the squamous cell carcinomas using a PCR-based line blot assay. Among the HPV positive cancers, the overall type distribution of the major high-risk HPV types was as follows: HPV 16 (66.7%), HPV 18 (19.4%), HPV 33 (5.6%), HPV 35 (5.6%), HPV 45 (5.6%), HPV 52 (2.8%), HPV 58(2.8%), HPV 59(2.8%) and HPV 73 (2.8%). Women participating in the community screening programme provided both a self-collected vaginal swab and a clinician-collected cervical swab for HPV DNA testing. Primary screening for high risk HPV was performed using the Digene Hybrid Capture 2 (hc2) assay. All hc2 positive samples by any one method of collection were further analyzed using the Roche PCR-based line blot for genotype determination. The prevalence of high risk HPV infection in this community-based screening population was 10.3% (19/185) using the clinician-collected and 7.0% (13/185) using the self-collected samples. The overall agreement between self-collected and clinician-collected samples was 92%; however among HPV-positive specimens, the HPV agreement was only moderate (39.1%). The most frequently detected HPV types in the Medchal community are HPV 52 and 16.
Our results suggest that the HPV type distribution in both cervical cancer tissues and in a general screening population from Andhra Pradesh is similar to that reported in India and other parts of the world. We also conclude that an effective vaccine targeting HPV 16 will reduce the cervical cancer burden in AP.
PMCID: PMC1345691  PMID: 16371167
3.  Downregulation of calcineurin activity in cervical carcinoma 
Calcineurin (CaN) is an important serine-threonine phosphatase (PP2B), which plays a crucial role in calcium-calmodulin mediated signal transduction events. Calcineurin has been implicated in pathogenesis of various diseases cardiac hypertrophy, diabetic neuropathy and Alzheimer's, however its role in neoplasia remains unclear.
In view of this we evaluated the calcineurin activity in serum and biopsy samples collected from women diagnosed with invasive squamous cell carcinoma of cervix. A significant reduction was observed in the calcineurin activity in cancer cervix patients compared to the control group. However the calcineurin activity remained unaltered in the cervical scrapes obtained from patients diagnosed with low-grade squamous intra epithelial lesions (LSIL). Interestingly the downregulation of calcineurin activity in squamous cell carcinomas was not accompanied by any significant change in DNA-binding affinity of the transcriptional factor NFAT (Nuclear Factor of Activated T-cells). All the squamous cell carcinoma samples used in the present study were positive for high-risk human papillomavirus (HPV) types.
The present study demonstrates the downregulation of calcineurin activity in squamous cell carcinoma of cervix with high risk HPV infection. We conclude that perturbations in calcineurin-mediated pathway may be involved in development of cervical neoplasia.
PMCID: PMC1087859  PMID: 15801986
cervical neoplasia; squamous cell carcinoma (SCC); calcineurin (PP2B/CaN); calmodulin (CaM)
4.  A Multicountry Evaluation of careHPV Testing, Visual Inspection With Acetic Acid, and Papanicolaou Testing for the Detection of Cervical Cancer 
Supplemental digital content is available in the text.
This study evaluates the feasibility and performance of careHPV, a novel human papillomavirus (HPV) DNA test, when used for screening women for cervical cancer in low-resource settings.
Methods and Materials
Clinician-collected (cervical) and self-collected (vaginal) careHPV specimens, visual inspection with acetic acid (VIA), and Papanicolaou test were evaluated among 16,951 eligible women in India, Nicaragua, and Uganda. Women with positive screening results received colposcopy and histologic follow-up as indicated. The positivity of each screening method was calculated overall, by site, and age. In addition, the clinical performance of each screening test was determined for detection of cervical intraepithelial neoplasia (CIN) grade 2 (CIN2+) and CIN grade 3.
Moderate or severe dysplasia or cancer (taken together as CIN2+) was diagnosed in 286 women. The positivity rate ranged between 2.4% to 19.6% for vaginal careHPV, 2.9% to 20.2% for cervical careHPV, 5.5% to 34.4% for VIA, and 2.8% to 51.8% for Papanicolaou test. Cervical careHPV was the most sensitive for CIN2+ (81.5%; 95% confidence interval [CI], 76.5–85.8) and CIN grade 3 (85.3%; 95% CI, 78.6–90.6) at all sites, followed by vaginal careHPV (69.6% and 71.3%, respectively). The sensitivity of VIA ranged from 21.9% to 73.6% and Papanicolaou test from 40.7% to 73.7%. The pooled specificities of cervical careHPV, vaginal careHPV, VIA, and Papanicolaou test were 91.6%, 90.6%, 84.2%, and 87.7%, respectively.
careHPV performed well in large multicountry demonstration studies conducted in resource-limited settings that have not previously been conducted this type of testing; its sensitivity using cervical samples or vaginal self-collected samples was better than VIA or Papanicolaou test. The feasibility of using careHPV in self-collected vaginal samples opens the possibility of increasing coverage and early detection in resource-constrained areas.
PMCID: PMC4047307  PMID: 24557438
Cancer prevention and control; Early detection; Cervical cancer; Low-resource settings; HPV

Results 1-4 (4)