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Background Human papillomavirus (HPV) type 67 is phylogenetically classified into Alphapapillomavirus species 9 (alpha-9) together with other carcinogenic types (HPV16, 31, 33, 35, 52 and 58), but is the only alpha-9 type defined as possibly carcinogenic. This study aimed to determine whole-genome sequences of HPV67 isolated from Japanese women with cervical cancer or cervical intraepithelial neoplasia (CIN) to better understand the genetic basis of the oncogenic potential of HPV67. Methods Total cellular DNA isolated from cervical exfoliated cells that were single positive for HPV67 (invasive cervical cancer, n = 2; CIN3, n = 6; CIN 2, n = 1; CIN1, n = 2; the normal cervix, n = 1) was subjected to PCR to amplify HPV67 DNA, followed by next generation sequencing to determine the complete viral genome sequences. Variant lineages/sublineages were assigned through viral whole-genome phylogenetic analysis. The transcriptional activity of the virus early promoter was assessed by luciferase reporter assays in cervical cancer cell lines. Results Phylogenetic analyses of HPV67 genomes from Japan (n = 12) revealed that 11 belonged to lineage A (sublineage A1, n = 9; sublineage A2, n = 2) and one belonged to lineage B. All cancer cases contained sublineage A1 variants, and one of these contained an in-frame deletion in the E2 gene. The long control region of the HPV67 genome did not induce transcription from the virus early promoter in HeLa cells, but showed weak transcriptional activity in CaSki cells. Conclusions The single detection of HPV67 in cervical cancer and precancer specimens strongly suggests the carcinogenic potential of this rare genotype. The phylogenetic analysis indicates a predominance of lineage A variants among HPV67 infections in Japan. Since only 23 complete genome sequences of HPV67 had been obtained until now, the newly determined genome sequences in this study are expected to contribute to further functional and evolutionary studies on the genetic diversity of HPV67.

The development of cervical cancer is initiated by human papillomavirus (HPV) infection and involves both viral and host genetic factors. Genome-wide association studies (GWAS) of cervical cancer have identified associations in the HLA locus and two loci outside HLA, but the principal genes that control infection and pathogenesis have not been identified. In the present study, we performed GWAS of cervical cancer in East Asian populations, involving 2609 cases and 4712 controls in the discovery stage and 1461 cases and 3295 controls in the follow-up stage. We identified novel-significant associations at 5q14 with the lead single nucleotide polymorphism (SNP) rs59661306 (P = 2.4 × 10-11) and at 7p11 with the lead SNP rs7457728 (P = 1.2 × 10-8). In 5q14, the chromatin region of the GWAS-significant SNPs was found to be in contact with the promoter of the ARRDC3 (arrestin domain-containing 3) gene. In our functional studies, ARRDC3 knockdown in HeLa cells caused significant reductions in both cell growth and susceptibility to HPV16 pseudovirion infection, suggesting that ARRDC3 is involved in the infectious entry of HPV into the cell. Our study advances the understanding of host genes that are responsible for cervical cancer susceptibility and guides future research on HPV infection and cancer development.

The TEAD family of transcription factors requires associating cofactors to induce gene expression. TEAD1 is known to activate the early promoter of human papillomavirus (HPV), but the precise mechanisms of TEAD1-mediated transactivation of the HPV promoter, including its relevant cofactors, remain unexplored. Here, we reveal that VGLL1, a TEAD-interacting cofactor, contributes to HPV early gene expression. Knockdown of VGLL1 and/or TEAD1 led to a decrease in viral early gene expression in human cervical keratinocytes and cervical cancer cell lines. We identified 11 TEAD1 target sites in the HPV16 long control region (LCR) by in vitro DNA pulldown assays; 8 of these sites contributed to the transcriptional activation of the early promoter in luciferase reporter assays. VGLL1 bound to the HPV16 LCR via its interaction with TEAD1 both in vitro and in vivo. Furthermore, introducing HPV16 and HPV18 whole genomes into primary human keratinocytes led to increased levels of VGLL1, due in part to the upregulation of TEADs. These results suggest that multiple VGLL1/TEAD1 complexes are recruited to the LCR to support the efficient transcription of HPV early genes. IMPORTANCE Although a number of transcription factors have been reported to be involved in HPV gene expression, little is known about the cofactors that support HPV transcription. In this study, we demonstrate that the transcriptional cofactor VGLL1 plays a prominent role in HPV early gene expression, dependent on its association with the transcription factor TEAD1. Whereas TEAD1 is ubiquitously expressed in a variety of tissues, VGLL1 displays tissue-specific expression and is implicated in the development and differentiation of epithelial lineage tissues, where HPV gene expression occurs. Our results suggest that VGLL1 may contribute to the epithelial specificity of HPV gene expression, providing new insights into the mechanisms that regulate HPV infection. Further, VGLL1 is also critical for the growth of cervical cancer cells and may represent a novel therapeutic target for HPV-associated cancers.

金沢大学医薬保健研究域医学系, Background: Human papillomavirus (HPV) infection is a primary cause of cervical cancer. Although epidemiologic study revealed that carcinogenic risk differs according to HPV genotypes, the expression patterns of HPV-derived transcripts and their dependence on HPV genotypes have not yet been fully elucidated. Methods: In this study, 382 patients with abnormal cervical cytology were enrolled to assess the associations between HPV-derived transcripts and cervical intraepithelial neoplasia (CIN) grades and/or HPV genotypes. Specifically, four HPV-derived transcripts, namely, oncogenes E6 and E6*, E1^E4, and viral capsid protein L1 in four major HPV genotypes-HPV 16, 18, 52, and 58-were investigated. Results: The detection rate of E6/E6*increased with CIN progression, whereas there was no significant change in the detection rate of E1^E4 or L1 among CIN grades. In addition, we found that L1 gene expression was HPV type-dependent. Almost all HPV 52-positive specimens, approximately 50% of HPV 58-positive specimens, around 33% of HPV 16-positive specimens, and only one HPV18-positive specimen expressed L1. Conclusions: We demonstrated that HPV-derived transcripts are HPV genotype-dependent. Especially, expression patterns of L1 gene expression might reflect HPV genotype-dependent patterns of carcinogenesis. © 2020 The Author(s).

Persistent infection with oncogenic human papillomaviruses (HPVs) causes cervical cancer, accompanied by the accumulation of somatic mutations into the host genome. There are concomitant genetic changes in the HPV genome during viral infection; however, their relevance to cervical carcinogenesis is poorly understood. Here, we explored within-host genetic diversity of HPV by performing deep-sequencing analyses of viral whole-genome sequences in clinical specimens. The whole genomes of HPV types 16, 52, and 58 were amplified by type-specific PCR from total cellular DNA of cervical exfoliated cells collected from patients with cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC) and were deep sequenced. After constructing a reference viral genome sequence for each specimen, nucleotide positions showing changes with >0.5% frequencies compared to the reference sequence were determined for individual samples. In total, 1,052 positions of nucleotide variations were detected in HPV genomes from 151 samples (CIN1, n = 56; CIN2/3, n = 68; ICC, n = 27), with various numbers per sample. Overall, C-to-T and C-to-A substitutions were the dominant changes observed across all histological grades. While C-to-T transitions were predominantly detected in CIN1, their prevalence was decreased in CIN2/3 and fell below that of C-to-A transversions in ICC. Analysis of the trinucleotide context encompassing substituted bases revealed that TpCpN, a preferred target sequence for cellular APOBEC cytosine deaminases, was a primary site for C-to-T substitutions in the HPV genome. These results strongly imply that the APOBEC proteins are drivers of HPV genome mutation, particularly in CIN1 lesions. IMPORTANCE HPVs exhibit surprisingly high levels of genetic diversity, including a large repertoire of minor genomic variants in each viral genotype. Here, by conducting deep-sequencing analyses, we show for the first time a comprehensive snapshot of the within-host genetic diversity of high-risk HPVs during cervical carcinogenesis. Quasispecies harboring minor nucleotide variations in viral whole-genome sequences were extensively observed across different grades of CIN and cervical cancer. Among the within-host variations, C-to-T transitions, a characteristic change mediated by cellular APOBEC cytosine deaminases, were predominantly detected throughout the whole viral genome, most strikingly in low-grade CIN lesions. The results strongly suggest that within-host variations of the HPV genome are primarily generated through the interaction with host cell DNA-editing enzymes and that such within-host variability is an evolutionary source of the genetic diversity of HPVs.

Recent large-scale genomics studies of human papillomaviruses (HPVs) have shown a high level of genomic variability of HPV16, the most prevalent genotype in HPV-associated malignancies, and provided new insights into the biological and clinical relevance of its genetic variations in cervical cancer development. Here, we performed deep sequencing analyses of the viral genome to explore genetic variations of HPV16 that are prevalent in Japan. A total of 100 complete genome sequences of HPV16 were determined from cervical specimens collected from Japanese women with cervical intraepithelial neoplasia and invasive cervical cancer, or without cervical malignancies. Phylogenetic analyses revealed the variant distribution in the Japanese HPV16 isolates, overall, lineage A was the most prevalent (94.0%), in which sublineage A4 was dominant (52.0%), followed by sublineage A1 (21.0%). The relative risk of sublineage A4 for cervical cancer development was significantly higher compared to sublineages A1/A2/A3 (odds ratio = 6.72, 95% confidence interval = 1.78&ndash, 28.9). Interestingly, a novel cluster of variants that branched from A1/A2/A3 was observed for the Japanese HPV16 isolates, indicating that unique HPV16 variants are prevalent among Japanese women.

Persistent infection with oncogenic human papillomavirus (HPV) causes cervical cancer. However, viral genetic changes during cervical carcinogenesis are not fully understood. Recent studies have revealed the presence of adenine/thymine-clustered hypermutation in the long control region of the HPV16 genome in cervical intraepithelial neoplasia (CIN) lesions, and suggested that apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) proteins, which play a key role in innate immunity against retroviral infection, potentially introduce such hypermutation. This study reports for the first time the detection of adenine/thymine-clustered hypermutation in the E2 gene of HPV16 isolated from clinical specimens with low- and high-grade CIN lesions (CIN1/3). Differential DNA denaturation PCR, which utilizes lower denaturation temperatures to selectively amplify adenine/thymine-rich DNA, identified clusters of adenine/thymine mutations in the E2 gene in 4 of 11 CIN1 (36.4%), and 6 of 27 CIN3 (22.2%) samples. Interestingly, the number of mutations per sample was higher in CIN3 than in CIN1. Although the relevance of E2 hypermutation in cervical carcinogenesis remains unclear, the observed hypermutation patterns strongly imply involvement of APOBEC3 proteins in editing the HPV16 genome during natural viral infection.

Apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like (APOBEC) proteins are cellular DNA/RNA-editing enzymes that play pivotal roles in the innate immune response to viral infection. APOBEC3 (A3) proteins were reported to hypermutate the genome of human papillomavirus 16 (HPV16), the causative agent of cervical cancer. However, hypermutation did not affect viral DNA maintenance, leaving the exact role of A3 against HPV infection elusive. Here we examine whether A3 proteins affect the virion assembly using an HPV16 pseudovirion (PsV) production system, in which PsVs are assembled from its capsid proteins L1/L2 encapsidating a reporter plasmid in 293FT cells. We found that co-expression of A3A or A3C in 293FT cells greatly reduced the infectivity of PsV. The reduced infectivity of PsV assembled in the presence of A3A, but not A3C, was attributed to the decreased copy number of the encapsidated reporter plasmid. On the other hand, A3C, but not A3A, efficiently bound to L1 in co-immunoprecipitation assays, which suggests that this physical interaction may lead to reduced infectivity of PsV assembled in the presence of A3C. These results provide mechanistic insights into A3s’ inhibitory effects on the assembly phase of the HPV16 virion.

After trauma or excision of malignant tumor, it is difficult to achieve satisfactory results when reconstructing deformed eyelids and the socket for an ocular prosthesis. The authors demonstrate examples of successful reconstruction for a prosthetic eye that provided adequate and aesthetic soft-tissue support achieved by applying a three-step surgical procedure of reconstruction of the eye socket, the eyelids, and the tarsus and eyelid margin. Because it is highly vascularized and its distal end can be divided into two or three portions for easy three-dimensional reconstruction, the expanded forehead flap alone, with a galea flap, or with a free rectus abdominis muscle perforator flap was used. The expanded forehead flap also provides excellent thin upper lid contour and good color-matching with a recipient site. For the eye socket, sufficient volume of tissue was provided from the expanded forehead flap with or without a galea or a free rectus abdominis muscle perforator flap, and a deep and convex fornix was formed. This resulted in a good fit and in stability of the ocular prosthesis. The surface and the inner lining of the eyelids were reconstructed using portions of the expanded forehead flap. For the tarsus and eyelid margin, conventional reconstruction techniques use cartilage of the concha, which has limitations of length and which does not fit the shape of the tarsal margin. The authors used the scapha composite graft, and a natural shape and good elasticity resulted.

High prevalence of infection with high-risk human papilloma virus (HPV) ranging from 25 to 100% (average 31%) was observed in breast cancer (BC) patients in Singapore using novel DNA chip technology. Early stage of BC demonstrated higher HPV positivity, and BC positive for estrogen receptor (ER) showed significantly higher HPV infection rate. This unique association of HPV with BC in vivo prompted us to investigate a possible involvement of HPV in early stages of breast carcinogenesis. Using normal breast epithelial cells stably transfected with HPV-18, we showed apparent upregulation of mRNA for the cytidine deaminase, APOBEC3B (A3B) which is reported to be a source of mutations in BC. HPV-induced A3B overexpression caused significant γH2AX focus formation, and DNA breaks which were cancelled by shRNA to HPV18 E6, E7 and A3B. These results strongly suggest an active involvement of HPV in the early stage of BC carcinogenesis via A3B induction.

Viral genetic diversity within infected cells or tissues, called viral quasispecies, has been mostly studied for RNA viruses, but has also been described among DNA viruses, including human papillomavirus type 16 (HPV16) present in cervical precancerous lesions. However, the extent of HPV genetic variation in cervical specimens, and its involvement in HPV-induced carcinogenesis, remains unclear. Here, we employ deep sequencing to comprehensively analyze genetic variation in the HPV16 genome isolated from individual clinical specimens. Through overlapping full-circle PCR, approximately 8-kb DNA fragments covering the whole HPV16 genome were amplified from HPV16-positive cervical exfoliated cells collected from patients with either low-grade squamous intraepithelial lesion (LSIL) or invasive cervical cancer (ICC). Deep sequencing of the amplified HPV16 DNA enabled de novo assembly of the full-length HPV16 genome sequence for each of 7 specimens (5 LSIL and 2 ICC samples). Subsequent alignment of read sequences to the assembled HPV16 sequence revealed that 2 LSILs and 1 ICC contained nucleotide variations within E6, E1 and the non-coding region between E5 and L2 with mutation frequencies of 0.60% to 5.42%. In transient replication assays, a novel E1 mutant found in ICC, E1 Q381E, showed reduced ability to support HPV16 origin-dependent replication. In addition, partially deleted E2 genes were detected in 1 LSIL sample in a mixed state with the intact E2 gene. Thus, the methods used in this study provide a fundamental framework for investigating the influence of HPV somatic genetic variation on cervical carcinogenesis.

A VeraCode-allele-specific primer extension (ASPE) method was applied to the detection and genotyping of human papillomavirus (HPV)-DNA. Oligonucleotide primers containing HPV-type-specific L1 sequences were annealed to HPV-DNA amplified by PGMY-PCR, followed by ASPE to label the DNA with biotinylated nucleotides. The labeled DNA was captured by VeraCode beads through hybridization, stained with a streptavidin-conjugated fluorophore, and detected by an Illumina BeadXpress® reader. By using this system, 16 clinically important HPV types (HPV6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68) were correctly genotyped in a multiplex format. The VeraCode-ASPE genotyping of clinical DNA samples yielded identical results with those obtained by validated PGMY-reverse blot hybridization assay, providing a new platform for high-throughput genotyping required for HPV epidemiological surveys.

In gene therapy trials, adeno-associated virus (AAV) vectors are injected directly into target tissues such as muscle and liver. Direct injection can lead to the introduction of a low level of the vector into blood circulation. To determine the systemic effects of the vector released in the blood, we extensively examined the biodistribution of intravenously administered AAV serotype 2 (AAV2) vector in cynomolgus monkeys. Although the vector distribution pattern varied from monkey to monkey, the vector DNA was maintained in the various tissues beyond 7 months post-inoculation (pi). The vector DNA was detected in the lymphoid tissues, particularly in the spleen, more frequently and at a much higher level than in the other tissues tested (i.e., brain, lung, liver, heart, gallbladder, pancreas, colon, kidney, ovary, uterus, etc.). The expression of a transgene was detected in the lymph nodes at 3 months pi. The distribution of two pseudotyped vectors, AAV2/10 and AAV2/11, was similar to that of the AAV2 vector. The present results suggest that when introduced intravenously, the AAV vector DNA persists and may induce transgene expression in various monkey tissues. Thus, the possibility of inadvertent gene transfer to various non-target tissues should be considered in a gene therapy strategy with an AAV vector.

We demonstrated the presence of two adeno-associated viruses (AAVs), designated AAV10 and AAV11, in cynomolgus monkeys by isolating and sequencing the entire viral coding regions from the monkey DNA. AAV10 and AAV11 capsid proteins shared 84% and 65%, respectively, of amino acids with AAV2. A phylogenetic analysis of AAV capsid proteins showed that AAV10 and AAV11 resembled most AAV8 and AAV4, respectively. To characterize the capsid protein, we pseudotyped an AAV2 vector with the monkey AAV capsid proteins and examined the resulting pseudotypes AAV2/10 and AAV2/11, in comparison with the AAV2 vector, for their host ranges in cell lines and tissue tropism in mice. AAV2/10 and AAV2/11 transduced primate cells less efficiently than AAV2. Whereas AAV2 transduced undifferentiated C2C12 mouse myoblasts more efficiently than differentiated ones, AAV2/10 and AAV2/11 transduced the undifferentiated myoblasts less efficiently than differentiated ones. Three weeks after injection to the muscle of the hind legs, AAV2/10 and AAV2 induced transgene expression similarly, but AAV2/11 did not transduce the skeletal muscle. Six weeks after systemic administration, transduced vector DNA was detected by PCR in the liver and spleen of mice inoculated with AAV2, in the liver, heart, muscle, lung, kidney, and uterus of mice with AAV2/10, and the muscle, kidney, spleen, lung, heart, and stomach of mice with AAV2/11. Mouse antisera against capsid protein VP2 of the three AAVs neutralized the respective vector particles in a type-specific manner. The results indicate that AAV10 and AAV11 capsid proteins, which are antigenically distinct from each other and AAV2, are likely to determine their host ranges and tissue tropism that are different from AAV2s, suggesting that cynomolgus AAVs could provide a broader choice of pseudotype AAV vectors for gene therapy.

Background Co-infection of multiple genotypes of human papillomavirus (HPV) is commonly observed among women with abnormal cervical cytology, but how different HPVs interact with each other in the same cell is not clearly understood. A previous study using cultured keratinocytes revealed that genome replication of one HPV type is inhibited by co-existence of the genome of another HPV type, suggesting that replication interference occurs between different HPV types when co-infected; however, molecular mechanisms underlying inter-type replication interference have not been fully explored. Methods Replication interference between two most prevalent HPV types, HPV16 and HPV18, was examined in HPV-negative C33A cervical carcinoma cells co-transfected with genomes of HPV16 and HPV18 together with expression plasmids for E1/E2 of both types. Levels of HPV16/18 genome replication were measured by quantitative real-time PCR. Physical interaction between HPV16/18 E1s was assessed by co-immunoprecipitation assays in the cell lysates. Results The replication of HPV16 and HPV18 genomes was suppressed by co-expression of E1/E2 of heterologous types. The interference was mediated by the heterologous E1, but not E2. The oligomerization domain of HPV16 E1 was essential for HPV18 replication inhibition, whereas the helicase domain was dispensable. HPV16 E1 co-precipitated with HPV18 E1 in the cell lysates, and an HPV16 E1 mutant Y379A, which bound to HPV18 E1 less efficiently, failed to inhibit HPV18 replication. Conclusions Co-infection of a single cell with both HPV16 and HPV18 results in replication interference between them, and physical interaction between the heterologous E1s is responsible for the interference. Heterooligomers composed of HPV16/18 E1s may lack the ability to support HPV genome replication.