Human papilloma virus genotyping, variants and viral load in tumors, squamous intraepithelial lesions, and controls in a north Indian population subset

Influence of TLR4 and TLR9 polymorphisms and haplotypes on multiple hrHPV infections and HPV16 copy number in cervical cancer and cervicitis

Genetic polymorphism in pathogen recognition receptors tends to influence infection, disease susceptibility, and progression. We analyzed the association of TLR4 and TLR9 gene polymorphisms with multiple hrHPV infections and HPV16 copy number in cervicitis and cervical cancer. A total of 440 cervical cancer, cervicitis, and healthy individuals were studied using PCR-based assays. Student t-test, chi-square test, Welch's t-test, and Fisher's Exact test were utilized to evaluate the association of HPV infection with polymorphisms. Haploview and FAMHAP were used to analyze haplotype association with HPV infection and viral load. Study results revealed HPV45 infection as the most common one in cervical cancer after HPV16, and one-fourth HPV positive cervical cancer patients possessed multiple HPV infections. Mean HPV16 copy number of 264.4 ± 58.7 and 2.1 ± 3.3 copies/cell was detected in cervical cancer and cervicitis, respectively. TLR4 rs10759931 was protective against multiple hrHPV infections. TLR4 haplotype ACAC was associated with an increased risk of multiple hrHPV infections. TLR9 SNPs rs187084, rs352140, and rs352139 were associated with decreased risk of high HPV16 copy number. Augmentation of efforts for the multivalent HPV vaccination in India is suggested. The analyzed polymorphisms were shown to modulate hrHPV co-infections and HPV16 viral load that warrants further analysis.

Association of DNA Repair Genes XRCC1 and APE-1 with the Risk of Cervical Cancer in North Indian population

BACKGROUNDS

Cervical cancer (CC) is one of the leading cause of death in women worldwide, HPV infection is the major risk factor in the disease development, 0and however other risk factor such as chemical carcinogens, genetic susceptibility and altered immune system are also a cause of the disease progression. In the light of the above statement we studied the base excision repair pathway (BER).

METHODS

We identified and studied the association of Single Nucleotide polymorphisms in the DNA repair genes of XRCC1 (Arg194Trp, Arg399G,) and APE-1Asp/148Glu to the susceptibility of cervical cancer (CC) in North Indian population. In our study of cases (n=102). Controls (n=109) were recruited from among women without cervical abnormalities. Genotypes were determined by PCR-CTPP method, Taking DNA from peripheral blood in a case control study.

RESULTS

A positive association was observed between the polymorphisms of XRCC1 genes, that is, in codons 194 (P=0.03, odds ratio (OR) =2.39, 95% confidence interval (CI)=5.2-1.1), 280 (P=0.01, OR=4.1, 95% CI=11.5-1.3) and 399 (P=0.01, OR=3.4, 95% CI=8.6-1.3) while APE-1 genotype GG (p=0.03,odds ratio(OR)=0.2,95% confidence interval (CI)=0.97-0.004) we observed a statistically significant protective role in developing cervical cancer.

CONCLUSION

Our results suggested that, XRCC1 gene is an important candidate gene for susceptibility to cervical cancer. Although the sample size was small, the present study indicate a statistical association between cervical cancer and XRCC1 SNPs. Future studies are needed that may provide a better understanding of the association between gene polymorphism and cervical carcinoma risk.
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Prevalence of high-risk human papilloma virus types and cervical smear abnormalities in female sex workers in Chandigarh, India

PURPOSE

Cervical cancer is the most common cancer among women in developing nations. Nearly 90% of the cases have been linked to the presence of high-risk human papillomavirus (hrHPV) types 16 and 18. The risk of cervical cancer may be high in female sex workers (FSWs) due to multiple sexual partners. This study aimed to determine the prevalence of cytological abnormalities and hrHPV types 16 and 18 in FSWs in Chandigarh, North India using the liquid-based cytology (LBC) approach.

MATERIALS AND METHODS

The cervical brush samples were collected from 120 FSW and 98 age-matched healthy controls (HCs). These were subjected to pap smear using conventional method, LBC and the detection of hrHPV types 16 and 18 was carried out using polymerase chain reaction.

RESULTS

The LBC samples showed better cytological details and also reduced the number of unsatisfactory smears from 11% in Pap to 1.5% in the LBC. A significantly higher number of inflammatory smears were reported in FSWs (51.7% vs. 34.7%, P = 0.01). The hrHPV types 16/18 were detected in 33/120 (27.5%) FSW versus 23/98 (23.5%) HCs. The risk of acquiring hrHPV was higher in FSWs, who had age at first sex ≤25 years, higher income and the habit of smoking.

CONCLUSION

The high prevalence of hrHPV among FSWs and HCs suggests the need for the implementation of effective National Screening Programme for early detection of hrHPV types to decrease the burden of cervical cancer, especially in high-risk population.

Alteration of Human Papillomavirus Type 16 Genetic and Epigenetic Profiles in Cervical Cancer Patients Is Indicative of Poor Disease Prognosis: A Cohort Analysis

Objective

Aim of this study was to assess the changes in genetic and epigenetic profiles of human papillomavirus type 16 (HPV16), if any, in primary cervical cancer (CaCx) and corresponding plasma before and after therapy for possible prognostic evaluation.

Methods

The genetic (integration status) and epigenetic (methylation of enhancer, early promoter, and late promoter sequences) profiles of HPV16 were analyzed in pretherapy CaCx (n = 46), corresponding plasma, posttherapy cervical swabs (n = 39), and corresponding plasma from a single patient cohort. Quantitative viral load was also measured in these HPV16-positive primary CaCx and posttherapy cervical swabs.

Results

Presence of HPV16 in the patients’ plasma before/after therapy was significantly (P= 0.03) associated with higher viral load in the primary tumor site. Human papillomavirus type 16 integration and hypomethylation of the early (14 of 29,Z= 4.47,P< 0.01) and late promoters (20 of 29,Z= 3.74,P< 0.01) were more prevalent in the plasma than the corresponding pretherapy CaCx samples. However, the dissimilarity in integration status (5 of 24) was less evident between posttherapy cervical swabs and corresponding plasma, although hypomethylation of the early promoter and hypermethylation of the late promoter (8 of 24,Z= 2.6,P< 0.01) was seen in posttherapy plasma samples. Whereas in the posttherapy swabs, integrated (22 of 29) or mixed (7 of 29) form of HPV16 prevailed with hypomethylation of the enhancer (6 of 29,Z= 2.0,P< 0.05) and late promoter (18 of 29,Z= 4.4,P< 0.01) compared with the corresponding primary tumors. The patients having high HPV16 copy number in pretherapy and posttherapy cervical lesions and hypomethylation of early promoter/late promoter in the corresponding plasma showed increased disease recurrence with distant metastases.

Conclusions

The genetic-epigenetic profile of HPV16 in pretherapy/posttherapy CaCx samples showed significant association with disease prognosis.

Human papillomavirus (HPV) types 16 and 18 in liquid-based cervical cytology samples

Human papillomavirus (HPV) DNA testing is replacing cervical cytology as a primary cervical cancer screening tool. The aim of this study was to determine the frequency of occurrence of HPV types 16 and 18 in liquid-based cytology (LBC) cervical samples in our set-up. This study comprised of 302 LBC cervical samples. HPV 16 and HPV 18 were detected by polymerase chain reaction (PCR), and the results were compared between normal (n = 155), inflammatory (n = 99), squamous (n = 37) and glandular abnormalities (n = 11). Of our patient cohort, 73.8 % was ≤40 years old. We found HPV 16 DNA in 91/302 (30.1 %) cases and HPV 18 DNA in 21/302 (6.95 %). HPV types 16 and 18 were detected in 25.8 and 4.5 % cytologically normal samples, respectively. HPV 16 was positive in 29.3 % of inflammatory samples. Squamous cervical abnormalities were more often HPV positive (HPV 16 in 48.6 %; HPV 18 in 29.7 %) than glandular abnormalities (36.4 and 18.2 %, respectively). We found high-risk HPV DNA in more than one third of the tested women. A good number of these HPV-positive cases were negative in cervical cytology.

Physical and methylation status of human papillomavirus 16 in asymptomatic cervical infections changes with malignant transformation

AIMS

To evaluate how the genetic and epigenetic profile of human papillomavirus 16 (HPV16) changes from asymptomatic cervical infections to cervical cancer (CaCx) development.

METHODS

HPV16 physical status, methylation of its early-late promoters and its upstream enhancer sequences were analysed in samples from asymptomatic cervical infections (n=89), pre-neoplastic lesions (low and high grade squamous intraepithelial lesions LSIL/HSIL, n=28) and primary CaCx (n=98).

RESULTS

In asymptomatic infection (65%, 58/89) and LSIL/HSIL (57%, 16/28) samples, the episomal form of HPV16 was predominant whereas integration of HPV16 was significantly (p=0.01) higher in CaCx (59%, 57/98). The integrated viral form was also present in asymptomatic (27%, 24/89) and LSIL/HSIL (25%, 7/28) samples. The methylation of the enhancer region was comparable (29-34%) among asymptomatic, LSIL/HSIL and CaCx samples. The episomal form exhibited relatively higher methylation of the early promoter (52%) than that of the late promoter (40%) in asymptomatic infection but the integrated form in asymptomatic carriers showed the opposite methylation pattern (early promoter (42%) vs late-promoter (54%)). A similar pattern was observed in LSIL/HSIL samples, with comparable frequencies (44%) of early and late promoter methylation of the episomal form. However, irrespective of HPV16 physical status, higher methylation of late promoter than that of early promoter was observed in CaCx samples. An inverse correlation was observed between HPV16 integration and overall methylation of the early promoter-enhancer region in CaCx (p=0.05), LSIL/HSIL (p=0.09) and asymptomatic samples (p=0.09).

CONCLUSIONS

Our study indicates that integration of HPV16 along with changes in methylation pattern of early and late promoters is essential for neoplastic transformation of asymptomatic cervical infections.

Advancing cervical cancer prevention in India: implementation science priorities

Cervical cancer is the leading cause of cancer mortality in India, accounting for 17% of all cancer deaths among women aged 30 to 69 years. At current incidence rates, the annual burden of new cases in India is projected to increase to 225,000 by 2025, but there are few large-scale, organized cervical cancer prevention programs in the country. We conducted a review of the cervical cancer prevention research literature and programmatic experiences in India to summarize the current state of knowledge and practices and recommend research priorities to address the gap in services. We found that research and programs in India have demonstrated the feasibility and acceptability of cervical cancer prevention efforts and that screening strategies requiring minimal additional human resources and laboratory infrastructure can reduce morbidity and mortality. However, additional evidence generated through implementation science research is needed to ensure that cervical cancer prevention efforts have the desired impact and are cost-effective. Specifically, implementation science research is needed to understand individual- and community-level barriers to screening and diagnostic and treatment services; to improve health care worker performance; to strengthen links among screening, diagnosis, and treatment; and to determine optimal program design, outcomes, and costs. With a quarter of the global burden of cervical cancer in India, there is no better time than now to translate research findings to practice. Implementation science can help ensure that investments in cervical cancer prevention and control result in the greatest impact.

Serum one-carbon metabolites and risk of cervical cancer

Most cases of cervical cancer are associated with human papilloma virus (HPV) infection of high risk types. In folate deficiency, heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) interferes with HPV16 viral capsid protein synthesis. We aimed to study the importance of 1-carbon metabolism in cervical carcinogenesis by examining serum vitamin B12 (cobalamin), homocysteine, folate levels, and the RNA and protein expression of HPV16 L1, L2, E6, E7, and to correlate them with hnRNP-E1 expression and HPV infection in normals, squamous intraepithelial lesions (SILs), and cervical cancer subjects. Serum cobalamin, folate, and homocysteine were estimated using kits, RNA by real time PCR and proteins by Western blotting. We observed that lower folate and vitamin B12 levels were associated with HPV infection. hnRNP-E1 progressively decreased from normals (100%) to SILs (75%) to cervical cancer (52.6%). The findings show that HPV16 E6 and E7 are overexpresed whereas HPV16 L1 and L2 are downregulated at mRNA and protein levels in cervical cancer as compared to normals and SILs. The results indicate that perhaps the reduced expression of hnRNP-E1 might be involved with the cervical cancer pathogenesis, with folate playing a role in the natural history of HPV infection.

Advancing cervical cancer prevention in India: implementation science priorities

Cervical cancer is the leading cause of cancer mortality in India, accounting for 17% of all cancer deaths among women aged 30 to 69 years. At current incidence rates, the annual burden of new cases in India is projected to increase to 225,000 by 2025, but there are few large-scale, organized cervical cancer prevention programs in the country. We conducted a review of the cervical cancer prevention research literature and programmatic experiences in India to summarize the current state of knowledge and practices and recommend research priorities to address the gap in services. We found that research and programs in India have demonstrated the feasibility and acceptability of cervical cancer prevention efforts and that screening strategies requiring minimal additional human resources and laboratory infrastructure can reduce morbidity and mortality. However, additional evidence generated through implementation science research is needed to ensure that cervical cancer prevention efforts have the desired impact and are cost-effective. Specifically, implementation science research is needed to understand individual- and community-level barriers to screening and diagnostic and treatment services; to improve health care worker performance; to strengthen links among screening, diagnosis, and treatment; and to determine optimal program design, outcomes, and costs. With a quarter of the global burden of cervical cancer in India, there is no better time than now to translate research findings to practice. Implementation science can help ensure that investments in cervical cancer prevention and control result in the greatest impact.

HPV genotyping and site of viral integration in cervical cancers in Indian women

Persistent HPV infection plays a major role in cervical cancer. This study was undertaken to identify HPV types in a cohort of Indian women with locally advanced cervical cancer as well as to determine the physical state and/or site of viral integration in the host genome. Pretreatment biopsies (n = 270) from patients were screened for HPV infection by a high throughput HPV genotyping assay based on luminex xMAP technology as well as MY09/11 PCR and SPF1/2 PCR. Overall HPV positivity was observed to be 95%, with HPV16 being most common (63%) followed by infection with HPV18. Integration status of the virus was identified using Amplification of Papillomavirus Oncogene Transcripts (APOT) assay in a subset of samples positive for HPV16 and/or HPV18 (n = 86) and with an adequate follow-up. The data was correlated with clinical outcome of the patients. Integration of the viral genome was observed in 79% of the cases and a preference for integration into the chromosomal loci 1p, 3q, 6q, 11q, 13q and 20q was seen. Clinical data revealed that the physical state of the virus (integrated or episomal) could be an important prognostic marker for cervical cancer.

Cervical cancer pathogenesis is associated with one-carbon metabolism

Cervical cancer is the most common cancer among women in India and a leading cause of death in these women. Most cases of cervical cancer are associated with human papillomavirus (HPV) infection of the high-risk type. It has been reported that aberrant DNA methylation can be associated with HPV infection and cervical cancer, and folate is directly involved in DNA methylation via one-carbon metabolism. We aimed to study the importance of one-carbon metabolism in the progression of cervical carcinogenesis by examining serum levels of vitamin B(12) (cobalamin), homocysteine, and folate and DNA methylation of tumor suppressor genes CDH1, HIC1, and Retinoic acid receptor beta (RARβ) amid these women ranging from normal to squamous intraepithelial neoplastic lesions (SIL) to cervical cancer. Blood and tissue samples were collected from normal (n = 35), SILs (n = 27), and cervical cancer patients (n = 38) in the age group of 26-70 years. Measurement of serum vitamin B(12), folate, and homocysteine were done using kits (Immulite). Promoter methylation was examined using methylation-specific PCR. The frequency of promoter hypermethylation for all the three tumor suppressor genes CDH1, HIC1, and RARβ showed an increasing trend from normal to dysplastic to invasive cervical cancer (p < 0.05). We observed that lower folate and vitamin B(12) status were associated with HPV infection. Taken together, our findings suggest a role of folate and vitamin B(12) in modulating the risk of cervical cancer and HPV infection. CDH1, HIC1, and RARβ genes can be used as potential biomarkers of cervical cancer risk assessment.

Human papillomavirus (HPV) genotypes and HPV16 variants and risk of adenocarcinoma and squamous cell carcinoma of the cervix

OBJECTIVE

Human papillomavirus (HPV) genotypes have been extensively studied in uterine cervix squamous cell carcinoma and HPV16 variants have been found to be associated with increased cancer risk, but few reports have been published on genotype distribution and HPV16 variant prevalence in adenocarcinoma tumors. The objective of this study was to analyze viral genotypes and HPV16 intratypic variants in cervical adenocarcinoma and squamous cell carcinoma of Italian women.

METHODS

A total of 39 invasive adenocarcinoma and 132 squamous cell carcinoma were reviewed and classified according to the modified WHO classification. HPV sequences were detected by nested PCR, using the broad spectrum consensus-primer pairs MY09/MY11 and the GP5+/GP6+ system, and genotyped by nucleotide sequence analysis. The HPV16-positive cases were amplified with E6-specific oligonucleotides and amplimers subjected to direct nucleotide sequence for variant identification.

RESULTS

The prevalence rate of any HPV infection was 72% in adenocarcinoma, and 85% in cervical squamous cell carcinoma. Among the 140 HPV-positive cancer cases, a total of nine mucosal HPV genotypes (HPV16, 18, 31, 33, 35, 39, 45, 58, 82) epidemiologically classified as carcinogenic or probably carcinogenic viruses were identified. The HPV type 16 was the most common viral type representing 64% and 73% of all infections in adenocarcinoma and squamous cell carcinoma, respectively. The E6 nucleotide sequence analysis of HPV16 isolates allowed the identification of Asian American (AA) variants in 33% of adenocarcinoma and in 20% of squamous cell carcinoma suggesting their stronger association with cancer of glandular origin.

CONCLUSION

These results suggest that HPV16 has a high prevalence in both invasive adenocarcinoma and squamous cell carcinoma from Italian patients. Moreover this study confirms previous observations, summarized in a systematic review of the literature, on the increased cancer risk of HPV16 AA class in adenoglandular cancer, possibly related to their more oncogenic behavior compared to HPV16 European variants.