Comparative analysis of human papillomavirus type 6 complete genomes originated from head and neck and anogenital disorders

A Case-Control Study of Photodynamic Therapy Combined with Thymosin in the Treatment of Condyloma Acuminatum in Anal Canal

A case-control study is performed in this paper to explore various possible effects and clinical value of the photodynamic therapy combined with thymosin for the treatment process of the condyloma acuminatum (CA) in the anal canal. For this purpose, a hundred (100) patients specifically with CA in the anal canal who were regularly treated in the hospital from February 2019 to April 2021 were recruited. The first group, that is, the control group, was treated with thymosin, whereas photodynamic therapy combined with thymosin was used as a treatment for the study group. The curative effect, clinical index, LTN, SP, TGF-β 1, TNF-α, CD3+, CD4+, CD8+, and the adverse reactions of incidence were compared between these groups. Moreover, 27 cases were observed to be obviously effective, 22 were observed to be effective, and a single case was observed to be ineffective. Thus, 98% is the total effective rate where a single case relapses. Likewise, in the control group, 15 cases were observed to be obviously effective, 28 effective, and 13 ineffective. Thus, 86% is the total rate of effectiveness where thirteen (13) cases relapse. We have observed that the study group has a higher rate of effectiveness than the control group and the rate of recurrence of the former group was slightly lower than that of the latter group, that is, the control group ( $P$  < 0.05). In addition, the time of symptom improvement, the amount of bleeding, the disappearance time of bloody stool, and the time of the first recurrence of the study group were observed to be lower than those of the control group ( $P$  < 0.05). In levels of LTN and SP, we have observed no or zero significant differences between these groups before treatment. However, LTN’s levels of both groups increased after the treatment, and SP’s level decreased. LTN’s level of the study group was observed to be higher than that of the other group, and SP’s level in the former group was lower than that in the latter group. Zero significant differences were observed in the TGF-β 1 and TNF-α’s levels between these groups before treatment, but the level of TGF-β 1 and TNF-α has increased and decreased, respectively, in both groups specifically after treatment. The level of TGF-β 1 in the former group was observed to be slightly higher than that in the latter group, that is, the control group, while TNF-α’s level in the study group was lower than that in the control group. We have not observed any significant difference in CD4+, CD3+, and CD8+ levels between these groups before treatment. However, after treatment, CD3+ and CD4+ levels increased, and the levels of CD8+ decreased in both groups, while CD3+ and CD4+ levels in the former group were evident to be higher than those in the latter group and the level of the CD8+ in the study group was observed to be lower than that in the control group. Finally, we compared the adverse reactions of incidence between these groups. There were 4 cases of tingling sensation and 1 case of redness and swelling in the group study along with a total incidence of 10%. There were 5 cases of tingling sensation and 2 cases of redness and swelling in the control group along with a total incidence of 14%. The incidence of adverse reactions in the study group was observed to be slightly lower than that in the control group, but a significant difference was not observed between these groups (χ2 = 0.378; $P$  > 0.05).

Genomic diversity of human papillomavirus type 6 from patients with condyloma acuminatum in Eastern China

OBJECTIVE

Human papillomavirus type 6 (HPV6) is the major etiological agent of anogenital warts both men and women. However, there is limited data on its genomic characterization in mainland China. The aim of this study was to understand the complete genomic diversity of HPV6 from patients with condyloma acuminatum (CA) and to explore the prevalence of different variant lineages/sublineages in eastern China.

METHODS

CA samples were collected in 3 hospitals in Shandong Province, China from January 2020 to March 2021. DNA extraction, PCR amplification, Sanger sequencing and sequence assembly were performed on HPV6-positive samples. The complete genomes obtained in this study were analyzed phylogenetically with global HPV6 sequences in GenBank database using MEGA 11.

RESULTS

A total of 55 complete genomic sequences of HPV6 were obtained in this study. They were classified as HPV6 variant lineage A (n = 20), sublineage B1 (n = 34) and sublineage B3 (n = 1) by phylogenetic analysis. Sequence alignment showed E1, E5A, E5B, L1, L2, LCR were relatively highly variable regions for sublineage B1 whereas E1, E5A, L2 for lineage A. Both phylogenetic trees of lineage A and sublineage B1 composed of two main branches. Chinese sequences of lineage A segregated into the major branch while those in sublineage B1 belonged to both branches. Genomic divergence between sequences from China and other countries was 0.00% - 0.33% in lineage A and 0.00% - 0.40% in sublineage B1.

CONCLUSIONS

This is the first study on HPV variant lineages circulating in mainland China. The results revealed that lineage A and sublineage B1 were prevalent and they had different highly variable regions. Further surveillance is needed to understand the dynamic change of different variants in the population.

Effect of E2 and long control region polymorphisms on disease severity in human papillomavirus type 11 mediated mucosal disease: Protein modelling and functional analysis

Interaction of the long control region (LCR) and the E2 protein of HPV11s was studied by in silico modelling and in vitro functional analysis. Genomes of HPV11s from fifteen (six known and nine novel) patients (two solitary papillomas, eleven respiratory papillomatoses of different severity, one condyloma acuminatum and one cervical atypia) were sequenced; E2 polymorphisms were analysed in silico by protein modelling. E2 and LCR variants were cloned into pcDNA3.1+ expression vector and into pALuc reporter vector, respectively, transfected to HEp2 cells alone or in different combinations and the luciferase activity was measured. In the E2, the ubiquitous polymorphism K308R caused stronger binding between the dimers but did not alter DNA binding; E2s with this polymorphism were significantly less efficient than the reference in promoting LCR activity. The unique polymorphism Q86K changed the negative surface charge of E2 (Q86) to positive (K86). The unique polymorphisms S245F and N247T in the hinge region disrupt a probable phosphorylation site in a RXXS motif targeted by protein kinase A and B, but do not affect directly the amino acids critical to nuclear transport. Both unique patterns partly restored the LCR activating potential disrupted by K308R. A unique E2/E4 ORF with a 58-bp deletion leading to a frameshift and an early stop codon resulted in a practically nonfunctional E2, and was associated with a papillomatosis with dysplasia. When testing existing LCR-E2 combinations, LCR with intrinsically lower enhancer capacity was only marginally activated by its E2 (R308 and the deletion mutant), and did not significantly exceed the activity of the reference LCR without E2. Combined with more potent LCRs associated with more severe disease, the activity was significantly higher, but still significantly lower than LCRs with reference E2. In summary, LCR-E2 interaction determined by their polymorphisms may explain, at least partly, differences in disease severity.

Coordinated Expression of HPV-6 Genes with Predominant E4 and E5 Expression in Laryngeal Papilloma

Laryngeal papilloma (LP) associated with human papillomavirus (HPV)-6 or -11 infection shows aggressive growth. However, the detailed molecular mechanism of virus-driven tumorigenesis has not been uncovered fully. HPV-6 viral gene expression and dynamic alterations were investigated with in situ localization of viral DNA and RNA in 13 patients with HPV-6-infected laryngeal papilloma. The average viral load was 4.80 × 10⁵ ± 1.86 × 10⁵ copies/ng DNA. E4, E5a, and E5b mRNAs accounted for 96% of the expression of 9 mRNAs. The alteration of viral DNA load during recurrence paralleled the mRNA expression levels, and the expression of all mRNAs showed a similar curve. E4, E5a, and E5b were expressed in the middle to upper part of the epithelium and were co-expressed in the same cells. E4 immunohistochemistry demonstrated an extensively positive reaction in the upper cell layer in accordance with E4 mRNA expression. These results suggest that individual viral genes are coordinately expressed for viral replication, virus release, and immunosurveillance avoidance. The newly developed E4-specific monoclonal antibody can be applied to further functional studies and clinical applications such as targeted molecular therapies.