Lineage analysis of human papillomavirus types 31 and 45 in cervical samples of Iranian women

Lineage analysis of human papillomavirus types 33 and 35 based on E6 gene in cervical samples from Tehran, Iran

Knowing the geographical distribution of lineages and sublineages of each HPV type is beneficial for the epidemiological and evolutionary studies of this virus. However, no studies have analyzed the variants of HPV 33 and 35 in Iranian women. To investigate the sequence variation of HPV 33 and 35 E6 gene, 42 and 92 samples were analyzed using nested PCR and sequencing, respectively. Sublineage analysis of HPV 33 showed that most of the samples belonged to the A2 sublineage (85.8%) and the remaining were classified to the A1 sublineage. Four mutations at positions A132C, A213C, A364C, and A480T were detected, among which two mutations A213C and A364C led to amino acid changes corresponding to positions K35N and N86H of amino acid, respectively, in 85.8% of samples. For HPV 35, two sublineages A1 and A2 were found in studied samples with a prevalence of 84.8 and 15.2%, respectively. Seven nucleotide changes were observed at positions of C127G/T, A130C, A131C, C136T, G249T, A326G, and C341T. Three of these mutations including A130C, G249T, and C341T resulted in amino acid changes at positions of E7D, C47F, and R78W in 4.4%, 3.3%, and 9.8% of samples, respectively. Concerning HPV 33 or 35 distinct lineages by histology/cytology status, no statistically significant differences were observed. Our results indicated that sublineages A2 of HPV 33 and A1 of HPV 35 were dominant in Tehran, Iran. However, more studies with larger sample sizes from different histopathological stages of cervix in various geographical regions of Iran are necessary to evaluate the pathogenicity risk of HPV 33 and 35 (sub)lineages in Iranian women with cervical cancer in the future.

Lineage and sublineage analysis of human papillomavirus types 51 and 59 in Iranian women

The current study aimed to investigate the sequence variations of HPV 51 and 59 in normal cervical cells and premalignant/malignant lesions of the cervix to know the common variants of HPV 51 and HPV 59 circulating in Iran. To do this, eighty-five samples that were infected by HPV 51 or HPV 59 were investigated using hemi-PCR to amplify the E6 gene followed by sequencing. Our findings indicated that lineages A and B were detected in 80.4% and 19.6% of HPV 51-positive cases, respectively. Among samples infected with HPV 59, 32.2% belonged to lineage A and 67.8% were classified with lineage B. In conclusion, our results showed that lineage A of HPV 51 and lineage B of HPV 59 are more prevalent and distributed in Iran.

Variant analysis of human papillomavirus type 52 in Iranian women during 2018-2020: A case-control study

Background and Aims

Knowing the regional variants of distinct human papillomavirus (HPV) types is valuable as it can be beneficial for studying their epidemiology, pathogenicity, and evolution. For this reason, the sequence variations of the E6 gene of HPV 52 were investigated among women with normal cervical cytology and premalignant/malignant cervical samples.

Methods

Sixty-four HPV 52-positive samples were analyzed using semi-nested PCR and sequencing.

Results

Our findings showed that all samples belonged to lineage A (61%) or B (39%). Among samples that were infected with the A lineage, sublineages A1 and A2 were detected and sublineage A1 was dominant. No association was found between lineages and stage of disease (p > 0.05).

Conclusion

Our results revealed that the A lineage, sublineage A1, and B lineage were common in Iranian women. Nevertheless, more studies with larger sample sizes are required to estimate the pathogenicity risk of HPV 52 lineages in Iranian women with cervical cancer.

Genetic diversity and bioinformatic analysis in the L1 gene of HPV genotypes 31, 33, and 58 circulating in women with normal cervical cytology

BACKGROUND

HPV-31, -33, and -58, along with HPV-45 and -52, account for almost 11% of HPV-associated cancers. Our previous studies showed that after HPV-16 and -51, HPV-58 was common and HPV-31 was as frequent as HPV-18 among Iranian women with normal cytology. Hence, in this study, we aimed to investigate the intra-type variations in L1 genes of HPV-58, -31, and -33 to find the predominant lineages circulating in women with normal cytology.

METHODS

Complete coding sequencing of the L1 gene was amplified and nucleotide and amino acid sequences were compared to those of the references. The selective pressure on L1 protein and whether the variations of the L1 genes embed in L1 loops, or N-glycosylated sites were also investigated.

RESULTS

B1, A, and A1 (sub)lineages were common in the HPV-58, -33, and -31 samples, respectively. Ninety nucleotide mutations were observed. Twenty nine nucleotide changes corresponded to nonsynonymous substitutions in which seventeen mutations were located in L1 loops. Only one codon position in HPV-58 sequences was found as the positive selection. No difference was observed in N-glycosylation sites between reference and understudied amino acid sequences.

CONCLUSION

In the current study, we reported, for the first time, the (sub) lineages, amino acid, and genetic diversity in the L1 gene of circulating HPV-58, -33, and -31, in women with normal cytology, in Iran. Such studies can not only have epidemiological values, but also aid to set vaccination programs.

Trends in Co-circulation of Oncogenic HPV Genotypes in Single and Multiple Infections among Unvaccinated Community

Cocirculation of multiple human papillomavirus (HPV) infections with low, probably high, and high‐risk genotypes are to be associated with various grades of infections and cancer progression. The oncogenic high‐risk HPVs are distributed and cocirculated throughout the world. This study was investigated to identify HPV genotypes related to genital disorders in unvaccinated women. The subjects were referred from clinics to a molecular lab for HPV testing in Iran as a low‐coverage vaccinated country. HPVs DNAs of cervical scrapping and genital tissue specimens of 1,133 un‐vaccinated women were genotyped using an in vitro diagnostic line probe (reverse hybridization) assay. In addition, phylogenetic trees were constructed on 100 MY09/MY11 polymerase chain reaction (PCR) amplicons of common genotypes of HPV L1 gene by Sanger sequencing. The mean age of the population study was 32.7 ± 8.0 and the mean age of HPV‐positive cases was 31.6 ± 7.8. HPV DNA was detected in 57.8% (655/1133) of women subjects and 42.2% (478/1133) of cases were undetected. Among 655 HPV‐positive cases, 639 subjects (56.4%) were related to defined genotypes and 16 subjects (1.4%) were untypeable. The highest prevalence rate of HPV genotypes was identified in the 25–34 years. The top 6 dominant HPVs in single and multiple genotypes were HPV6 (284/655 [43.4%]), HPV16 (111/655 [16.9%]), HPV31 (72/655 [11%]), HPV53 (67/655 [10.2%]), HPV11 (62/655 [9.5%]), and HPV52 (62/655 [9.5%]). Moreover, single, multiple and untypeable HPV genotypes were diagnosed as follows: 1 type (318/655 [48.5%]), 2 types (162/655 [24.8%]), 3 types (83/655 [12.7%]), 4 types (42/655 [6.5%]), more than 5 types (34/655 [5.3%]), and 1.4% un‐typeable subjects. The sequenced partial L1 gene of HPV genotypes (GenBank databases under the accession numbers: MH253467‐MH253566) confirmed and determined the cocirculated HPV genotypes' origins and addressed helpful insights into the future viral epidemiology investigations. Multiple HPV infections and cocirculation of various oncogenic HPV genotypes among the normal population (women and men) with asymptomatic forms are still challenging in unvaccinated communities. The preventive and organized surveillance programs for HPV screening are needed to be considered and compiled by health policy makers of low or unvaccinated countries.

Lineage and sublineage analysis of human papillomavirus type 56 in cervical samples of Iranian women

Understanding the regional lineages and sublineages of human papillomavirus type 56 (HPV 56) would be of great importance for further evolutionary, epidemiological, and biological investigations. To identify the distribution of lineages and sublineages of HPV 56 in Iran, the sequence variations of the E6 gene were analyzed in normal, premalignant, and malignant samples obtained from the cervix. In total, 58 HPV 56-positive samples were investigated by nested-PCR and followed by bidirectional direct nucleotide sequencing analysis. Both lineages A and B were identified in the studied samples. Lineage B was dominant as it was detected in 88.4% of all samples and the remaining samples belonged to lineage A (11.6%). Sublineages A1 and A2 were detected in 3.3% and 8.3% of all samples, respectively. With regard to the pathological stages of cervical specimens, no statistically significant differences were found in the three studied groups (p > 0.05). In conclusion, our findings showed that lineage B of HPV 56 was prevalent in Iran. However, further studies with a larger sample size are warranted to estimate the pathogenicity risk of HPV 56 lineages/sublineages to the progression of cervical cancer among Iranian women.

Lineage analysis of human papillomavirus type 39 in cervical samples of Iranian women

Background

The data with regards to the regional variants of distinct HPV types is of great value. Accordance with this, this study aimed to investigate the sequence variations of E6 gene and long control region of HPV 39 among normal, premalignant and malignant cervical samples in order to characterize the frequent HPV 39 variants circulating in Tehran, Iran.

Methods

In total, 70 cervical samples (45 normal, 16 premalignant, and 9 malignant samples) infected with HPV 39 were analyzed by nested-PCR and sequencing.

Results

Our results revealed that all samples belonged to A lineage. Almost all sequences (98.6%) were classified in A1 sublineage and only one sample (1.4%) was A2 sub lineage.

Conclusions

Our findings showed that lineages A, sublineage A1, is dominant in Tehran, Iran. However, the small sample size was the most important limitations of this study. Further studies with larger sample size from different geographical regions of Iran are necessary to estimate the pathogenicity risk of HPV 39 variants in this population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-021-01619-8.