Phylogenetic analysis of Human papillomavirus 16 variants isolated from Indian Breast cancer patients showed difference in genetic diversity with that of cervical cancer isolates

HPV-Associated Breast Cancer: Myth or Fact?

Some estimates place the proportion of human malignancies attributable to viruses at between 15 and 20 percent. Viruses including the human papillomavirus are considered an interesting but controversial etiological risk factor for breast cancer. HPV infection is anticipated to be an early trigger in breast cancer carcinogenesis, followed by cumulative alterations over time ("hit and run" mechanism) through synergy with other environmental factors. The association between HPV and breast cancer has not yet been verified. There are very conflicting data on the presence of HPV DNA in breast cancer samples, and we lack a clarified, exact mode of HPV transmission to the breast. In our review article we analyzed the up-to-date knowledge about the association of HPV and breast cancer. Furthermore, we summarized the available original research published since 2010. In conclusion, the complexity and inconsistency of the available results together with the relatively low prevalence of HPV infection requires extensive research with much larger studies and exact and unified diagnostic methods are required to better understand the role of the HPV in breast carcinogenesis.

Characterization of the Human Papillomavirus 16 Oncogenes in K14HPV16 Mice: Sublineage A1 Drives Multi-Organ Carcinogenesis

The study of human papillomavirus (HPV)-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.

Phylogenetic Analysis of HPV16 Isolated from Women with Cervical Cancer Based on L2 Gene Partial Sequence in the Province of Dhi-Qar, Iraq

BACKGROUND: As a causative agent for cervical cancer, the human papillomavirus (HPV) is well-recognized. Being a high-risk form, HPV16 is considered and has been confirmed to be associated specifically with cancer of the cervix. AIM: HPV16’s phylogenetic tree and genetic diversity are well known worldwide, but in Iraq, documents on HPV16 genetic diversity among women with cervical cancer are lacking; therefore, the present study focused on phylogenetic analysis of HPV16 isolated cervical cancer based on L2 gene partial sequence. METHODOLOGY: The current study focused on the investigation of HPV16 in women who suffer from cervical cancer. This survey was performed on 93 adult females suffering from cervical cancer during the period from 2017 to 2020. For the molecular study, DNA was extracted and subjected to a polymerase chain reaction (PCR) for detection and amplification of minor capsidprotein L2 gene. Nucleotide sequences of amplified capsid L2 gene were searched using the advanced simple local alignment search tool at GenBank (BLAST). RESULTS: Genetic screening on HPV16 L2 gene by conventional PCR showed that 60 (65%) of cervical cancer cases infected by HPV16 while only 5 (8%) of the healthy control group are positive for HPV16. The results of the NCBI-BLAST homology sequence showed that genetic variation appeared in four strains from five strains of HPV16. CONCLUSION: HPV16 from the main causative factors for cervical cancer with high genetic variation.

Genetic diversity and phylogenetic analysis of HPV 16 & 18 variants isolated from cervical specimens of women in Saudi Arabia

Human papillomavirus (HPV) are well known to be associated with the development of cervical cancer. HPV16 and HPV 18 are known as high-risk types and reported to be predominantly associated with cervical cancer. The prevalence and genetic diversity of HPV have been well documented globally but, in the Kingdom of Saudi Arabia, data on HPV genetic diversity are lacking. In this study, we have analyzed the genetic diversity of both HPV16 and HPV18 based on their L1 gene sequence because L1 gene is a major capsid protein gene and has been utilized to develop a prophylactic vaccine. In January 2011-2012, a total of forty samples from cervical specimens of women in Saudi Arabia were collected. The association of HPV16, HPV18 was detected by polymerase chain reaction, sequenced and submitted to GenBank. The sequences identity matrix and the phylogenetic relationship were analyzed with selected HPVs. The highest sequence identity (99.5%) for HPV16 and (99.3%) for HPV was observed with selected HPVs. The phylogenetic analysis results showed that HPVs from Saudi Arabia formed a closed cluster with African, Asian, East Asian as well as American HPVs distributed into multiple linages from various geographical locations. The results provided the valuable information about genetic diversity, but there is an urgent need to generate full genome sequence information which will provide a clearer picture of the genetic diversity and evolution of HPVs in Saudi Arabia. In conclusion, the generated data will be highly beneficial for developing molecular diagnostic tools, analyzing and correlating the epidemiological data to determine the risk of cervical cancer and finally to develop a vaccine for Saudi Arabian population.

Findings of multiple HPV genotypes in cervical carcinoma are associated with poor cancer-specific survival in a Swedish cohort of cervical cancer primarily treated with radiotherapy

Cervical cancer (CC) is one of the most common cancers in women and virtually all cases of CC are a result of a persistent infection of human papillomavirus (HPV). For disease detected in early stages there is curing treatment but when diagnosed late with recurring disease and metastasis there are limited possibilities. Here we evaluate HPV impact on treatment resistance and metastatic disease progression. Prevalence and distribution of HPV genotypes and HPV16 variants in a Swedish CC patient cohort (n=209) was evaluated, as well as HPV influence on patient prognosis. Tumor samples suitable for analysis (n=204) were genotyped using two different real-time PCR methods. HPV16 variant analysis was made using pyrosequencing. Results showed that HPV prevalence in the total series was 93%. Of the HPV-positive samples, 13% contained multiple infections, typically with two high-risk HPV together. Primary cure rate for the complete series was 95%. Recurrence rate of the complete series was 28% and distant recurrences were most frequent (20%). Patients with tumors containing multiple HPV-strains and particularly HPV genotypes belonging to the alpha 7 and 9 species together had a significantly higher rate of distant tumor recurrences and worse cancer-specific survival rate.