Exploring the association between the lineages of human papillomavirus type 16 and viral physical status in the development of cervical cancer in Iran

Q: How were HPV-16 lineages and viral physical status determined in the study?

Viral physical status was inferred from quantitative Real-Time PCR measurements of E2 and E6 and calculation of the E2/E6 ratio. HPV-16 lineages were assigned by full sequencing of the E6 gene.

Q: What viral physical status forms were analyzed, and how did they differ by disease group?

HPV-16 physical status was categorized into episomal, mixed, and integrated forms. The integrated form was more prevalent in invasive cervical cancer patients than in CIN I-III and normal groups.

Q: Did the study find a direct statistical difference in integration status across HPV-16 lineages overall?

Overall, no statistically significant differences were identified between HPV-16 lineages and integration status. However, when stratified by histology, an association between lineage D and the integrated form was observed.

Sep 23, 2026

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Study investigates whether HPV-16 lineages relate to viral physical status during cervical cancer development in Iran. DNA from 125 HPV-16–positive cervical samples (normal, precancerous, and cancerous) was analyzed by quantitative Real-Time PCR using the E2/E6 ratio to infer physical status, and the E6 gene was fully sequenced to assign lineages. Lineages A, C, and D were detected, with distinct integration prevalence in ICC versus CIN I-III and normal, and higher integrated levels in patients over 40 years. Associations by histology were found for lineage D.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages8

Reading Time20 min

AccessFree to download

Study background

HPV-16 integration and lineage hypotheses

Materials and methods

Sample collection and PCR-based assessment

E6 sequencing for lineage identification

Results

Distribution of HPV-16 lineages

Viral physical status forms and integration patterns

Associations with histology and age

Lineage-specific relationships after stratification

Conclusion and recommendations

[www. nature.com/scientificreports](www. nature.com/scientificreports) OPEN Exploring the association between the lineages of human papillomavirus type 16 and viral physical status in the development of cervical cancer in Iran Hassan Karami1,4, Rahim Soleimani-Jelodar2,4, Zohreh Khezeli1, Zabihollah Shoja3, ArashArashkia3, Sajad Varmazyar1 & Somayeh Jalilvand1􀀍 Human papillomaviruses (HPVs) are well-established etiological causes of invasive cervical cancer (ICC), with type 16 being the main contributor. This virus is often found to be integrated into the host genome in precancerous lesions and advanced cervical cancers. It is suggested that distinct lineages of HPV-16 differ in their persistence, carcinogenic potential, and geographic distribution. Given that genomic integration is one of the most critical steps in the development of cervical cancer, and lineage D has a higher propensity to integrate the viral genome into the host genome, it is necessary to conduct a study to investigate a possible relationship between HPV-16 lineages and physical status in Iran. In this study, a total of 125 laboratory-confirmed HPV-16-positive cervical samples (comprising 30 normal, 39 precancerous, and 56 cancerous specimens) were analyzed. The DNA level of E2 and E6 viral genes was measured using the quantitative Real-Time PCR method, and the E2/E6 ratio was used to calculate the physical status of the HPV-16 DNA in the studied samples. The full sequence of the E6 gene was also sequenced to determine HPV-16 lineages. Three lineages, A (32.8%), C (0.8%), and D (66.4%) of HPV-16, were found in this study. HPV-16 exhibits different integration profiles, with viral DNA detected in three forms: episomal, mixed, and integrated. The physical status of the genome was statistically different based on histology and age. The integrated form was more prevalent in ICC patients than in CIN I-III and normal groups (P=0.000048). Also, the integrated form of the genome was found in higher amounts in the age group >40 years in comparison to <40 years (P= 0.00117). Regarding lineages, no statistically significant differences were identified between HPV-16 lineages and the integration status. However, when the samples were stratified by histology status, an association between lineage D and integrated form was observed, while no association was found for lineage A. In conclusion, lineages A and D were found to be dominant in the Iranian population. Moreover, an association was found between lineage and integration status, as lineage D has a higher propensity to integrate than lineage A. However, it is recommended that further studies with larger sample sizes from different regions of Iran be conducted to estimate whether a specific lineage or sublineage has a higher chance of integrating into the host genome, persisting, and causing cancer. Keywords Human papillomavirus, HPV-16 lineage, Virus integration, Cervical cancer Human papillomaviruses (HPVs) are small and non-enveloped viruses genetically characterized by a circular double-stranded DNA that consists of early region genes (E1, E2, E4, E5, E6, and E7), late region genes (L1, L2), and an upstream regulatory region ( URR)1,2. There are over 400 types of HPVs with almost 45 mucosal types that classified into two main categories including high-risk (HR) [including 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68] and low-risk (LR) [e.g., 6, 11, 42, 43, and 44]1,3. These viruses are linked to the development 1Department of Virology, School of Public Health, Tehran University of Medical Sciences, Tehran 14155, Iran. 2Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 3Department of Virology, Pasteur Institute of Iran, Tehran, Iran. 4Hassan Karami, Rahim Soleimani-Jelodar are the authors contributed equally to this work. 􀀍 email: [sjalilvand@tums.ac.ir](sjalilv

FAQs

How were HPV-16 lineages and viral physical status determined in the study?

Viral physical status was inferred from quantitative Real-Time PCR measurements of E2 and E6 and calculation of the E2/E6 ratio. HPV-16 lineages were assigned by full sequencing of the E6 gene.

What viral physical status forms were analyzed, and how did they differ by disease group?

HPV-16 physical status was categorized into episomal, mixed, and integrated forms. The integrated form was more prevalent in invasive cervical cancer patients than in CIN I-III and normal groups.

Did the study find a direct statistical difference in integration status across HPV-16 lineages overall?

Overall, no statistically significant differences were identified between HPV-16 lineages and integration status. However, when stratified by histology, an association between lineage D and the integrated form was observed.

Sep 23, 2026

Uploaded by OmBimo