• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3961-3968
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• 2015

Background: Variants of human papillomavirus (HPV) show more oncogenicity than do prototypes. The HPV16 Asian variant (HPV16As) plays a major role in cervical cancer of Asian populations. Some amino acid changes in the E6 protein of HPV16 variants affect E6 functions such as p53 interaction and host immune surveillance. This study aimed to investigate activities of HPV16As E6 protein on modulation of expression of miRNA-21 as well as interferon regulatory factors (IRFs) 1, 3, 7 and c-fos. Materials and Methods: Vectors expressing E6 protein of HPV16As (E6D25E) or HPV16 prototype (E6Pro) were constructed and transfected into C33A cells. HCK1T cells expressing E6D25E or E6Pro were established by transducing retrovirus-containing E6D25E or 16E6Pro. The E6AP-binding activity of E6 and proliferation of the transfected C33A cells were determined. MiR-21 and mRNA of interesting genes were detected in the transfected C33A cells and/or the HCK1T cells, with or without treatment by culture medium from HeLa cells (HeLa-CM). Results: E6D25E showed binding activity with E6AP similar to that of E6Pro. Interestingly, E6D25E showed a higher activity of miR-21 induction than did E6Pro in C33A cells expressing E6 protein. This result was similar to the HCK1T cells expressing E6 protein, with HeLa-CM treatment. The miR-21 up-regulation significantly corresponded to its target expression. Different levels of expression of IRFs were also observed in the HCK1T cells expressing E6 protein. Interestingly, when treated with HeLa-CM, IRFs 1, 3 and 7 as well as c-fos were significantly suppressed in the HCK1T cells expressing E6D25E, whereas those in the HCK1T cells expressing E6Pro were induced. A similar situation was seen for IFN-${\alpha}$ and IFN-${\beta}$. Conclusions: E6D25E of the HPV16As variant differed from the E6 prototype in its activities on epigenetic modulation and immune surveillance and this might be a key factor for the important role of this variant in cervical cancer progression.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2073-2080
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• 2015

Background: The human papillomavirus (HPV) and its variants show wide geographical distribution and have been reported to cause cervical lesions. With cervical neoplasia as the leading cancer in Indian women, the aim of the present study was to evaluate the multiple infection HPV type distribution and variant genotypes in cervical samples from the coastal Karnataka region, India. Materials and Methods: A total of 212 samples were screened by nested polymerase chain reaction using PGMY9/11 and GP5+/6+ primers. HPV positive samples were sequenced to identify the types and a phylogenetic tree was constructed using the neighbor-joining method. Results: Sequence analysis identified a total of 14 HPV types distributed in 20%, 73.3% and 82.5% of non-malignant, pre-malignant [low grade squamous intraepithelial lesion (LSIL) and high grade squamous intraepithelial lesion (HSIL)] and cervical cancer samples. The distribution of high risk HPV in cancer samples was HPV 16, 76.4%, HPV18, 11.7%, HPV81, 2.9%, HPV31, 1.4%, HPV35, 1.4% and HPV 45, 1.4%. Multiple infections were observed in 11.8% of tumor samples with HPV 16 contributing to 62.5% of cases. In non-malignant samples, 20% of HPV positive samples were detected with HPV16, 82.3%, HPV33, 5.8% and HPV58, 5.8% and very low incidence of multiple infections. Comparative phylogenetic analysis of HPV variants identified 9 HPV sequences as new papillomavirus species, predominantly classified as European lineage type. Conclusions: The findings for HPV infections associated with progression of cervical cancer in coastal Karnataka region and HPV variant analysis provide baseline data for prevention and HPV vaccination programs.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.1151-1157
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• 2015

Human papillomavirus (HPV) is responsible for one of the most frequent sexually transmitted infections. The first phylogenetic analysis was based on a LCR region fragment. Nowadays, 4 variants are known: African (Af-1, Af-2), Asian-American (AA) and European (E). However the existence of sub-lineages of the European variant havs been proposed, specific mutations in the E6 and LCR sequences being possibly related to persistent viral infections. The aim of this study was a phylogenetic study of HPV16 sequences of endocervical samples from C${\acute{o}}$rdoba, in order to detect the circulating lineages and analyze the presence of mutations that could be correlated with malignant disease. The phylogenetic analysis determined that 86% of the samples belonged to the E variant, 7% to AF-1 and the remaining 7% to AF-2. The most frequent mutation in LCR sequences was G7521A, in 80% of the analyzed samples; it affects the binding site of a transcription factor that could contribute to carcinogenesis. In the E6 sequences, the most common mutation was T350G (L83V), detected in 67% of the samples, associated with increased risk of persistent infection. The high detection rate of the European lineage correlated with patterns of human migration. This study emphasizes the importance of recognizing circulating lineages, as well as the detection of mutations associated with high-grade neoplastic lesions that could be correlated to the development of carcinogenic lesions.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3603-3606
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• 2013

Background: To investigate the infection status and predominant genotype distribution of human papillomavirus (HPV) infection among Chinese patients with mucopurulent cervicitis (MPC) or cervical cancer (CC) in Hangzhou. Methods: Initially, 217 cases of healthy cervix controls (n=50), acute MPC (n=89), and CC (n=78) were included; samples were collected between January 1, 2010, and January 30, 2013. Cervical specimens were screened for HPV using a nested polymerase chain reaction assay and DNA sequencing. Results: Overall prevalence of HPV infection was 16.7% in the control group, 51.9% in the MPC group, and 84.4% in the CC group. The predominant genotype detected in all 3 groups was the oncogenic variant HPV 16 (55.8%, 17.3%, and 6.3% in the CC, MPC and control specimens, respectively), HPV58 was the second most predominant HPV type in CC (9.1%), MPC (8.6%), and control group (4.2%). Most or all of the genotypes were oncogenic in the three groups. Conclusions: Infection with HPV was found to be prevalent among Chinese women with MPC or CC and oncogenic variants were in the majority. Therefore, peoples who suffered MPC with HPV DNA positive should be regularly followed-up, for prevention and early treatment of cervical cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.599-606
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• 2012

The characterization of the whole genome of human papillomavirus type 16 (HPV16) from cervical cancer specimens with multiple infections in comparison with single infection samples as the oncogenic potential of the virus may differ. Cervical carcinoma specimens positive for HPV16 by PCR and INNO-LiPA were randomly selected for whole genome characterization. Two HPV16 single infection and six HPV16 multiple infection specimens were subjected to whole genome analysis by using conserved primers and subsequent sequencing. All HPV16 whole genomes from single infection samples clustered in the European (E) lineage while all multiple infection specimens belonged to the non-European lineage. The variations in nucleotide sequences in E6, E7, E2, L1 and Long control region (LCR) were evaluated. In the E6 region, amino acid changes at L83V were related to increased cancer progression. An amino acid variation N29S within the E7 oncoprotein significantly associated with severity of lesion was also discovered. In all three domains of the E2 gene non synonymous mutations were found. The L1 region showed various mutations which may be related to conformation changes of viral epitopes. Some transcription factor binding sites in the LCR region correlated to virulence were shown on GRE/1, TEF-1, YY14 and Oct-1. HPV16 European variant prone to single infection may harbor a major variation at L83V which significantly increases the risk for developing cervical carcinoma. HPV16 non-European variants prone to multiple infections may require many polymorphisms to enhance the risk of cervical cancer development.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8239-8245
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• 2016

The p53 gene is inactivated by the human papillomavirus (HPV) E6 protein in the majority of cervical cancers. Treatment of HeLa S3 cells with siRNA for HPV E6 permitted adenovirus-mediated transduction of a p53 gene linked to an upstream estrogen response element (ERE). Our previous study in non-siRNA treated HHUA cells, which are derived from an endometrial cancer and express estrogen receptor ${\beta}$, showed enhancing effects of an upstream ERE on adenovirus-mediated p53 gene transduction. In HeLa S3 cells treated with siRNA for HPV E6, adenovirus-mediated transduction was enhanced by an upstream ERE linked to a p53 gene carrying a proline variant at codon 72, but not for a p53 gene with arginine variant at codon 72. Expression levels of p53 mRNA and Coxsackie/adenovirus receptor (CAR) mRNA after adenovirus-mediated transfer of an ERE-linked p53 gene (proline variant at codon 72) were higher compared with those after non-ERE-linked p53 gene transfer in siRNA-treated HeLa S3 cells. Western blot analysis showed lower ${\beta}$-tubulin levels and comparatively higher p53/${\beta}$-tubulin or CAR/${\beta}$-tubulin ratios in siRNA-treated HeLa S3 cells after adenovirus-mediated ERE-linked p53 gene (proline variant at codon 72) transfer compared with those in non-siRNA-treated cells. Apoptosis, as measured by annexin V binding, was higher after adenovirus-mediated ERE-linked p53 gene (proline variant at codon 72) transfer compared with that after non-ERE-linked p53 gene transfer in siRNA-treated cells.

• Journal of Life Science
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• v.19 no.6
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• pp.765-769
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• 2009

Recent studies have reported that the distribution of HPV-16 sequence variation differs geographically, and more specifically that HPV-16 E6/E7 intratypic variants might carry a high risk for development of ICC (invasive cervical cancer) and CIN (cervical intraepithelial neoplasia) in a given population. To investigate the genetic diversities of HPV-16 E6/E7 oncogene by region, we collected nineteen HPV-16 isolates from sexually high-risk women in Busan, and analyzed the HPV-16 E6/E7 coding regions (nt 34 to 880) with HPV-16 E6/E7 specific PCR amplification. At the nucleotide levet eleven variants of the E6 genes and nine variants of the E7 genes were identified as follows: E6 T178G (n=l1), E6 T178A (n=l), E6 T350G (n=3), E6 A442C (n=2), E6 AI04T, E6 All1G, E6 C116T, E6 G145T, E6 T183G, E6 C335T, E6 G522C and E7 A647G (n=12), E7 A645C, E7 A777C, E7 G663A, E7 T732C, E7 T760C, E7 A775T, E7 T789C and E7 T795G, respectively. At the amino acid levet the isolated HPV-16 E6 and E7 genes showed eleven E6 variants: E6 D25E (n=12), E6 L83V (n=4), E6 E113D (n=2), E6 MIL, E6 Q3R, E6 P5S, E6 Q14H, E6 D25N, E6 127R, E6 H78Y, E6 C140S and three E7 variants: N29S (n=12), L28F, T72S. HPV16 E6 L83V, the dominant variant in the Caucasian population, showed relatively low frequencies in our study population. We elucidated that the dominant HPV-16 E6/E7 variants were HPV-16 E6 D25E (63.2%) and HPV-16 E7 N29S (63.2%), which were phylogenetically included in Asian lineage. Further study is needed to evaluate the risk of cervical cancer related HPV-16 E6/E7 intratypic variants in the Korean population.