Human leukocyte antigen class II DRB1*1302 allele protects against cervical cancer: At which step of multistage carcinogenesis?

Biomarkers differentiating regression from progression among untreated cervical intraepithelial neoplasia grade 2 lesions

BACKGROUND

Cervical intraepithelial neoplasia grade 2 (CIN2) is one of the precursor stages before cervical lesions develop into cervical cancer. The spontaneous development of CIN2 is ambiguous. One part of CIN2 lesions will progress to cervical intraepithelial neoplasia grade 3 or worse (CIN3+), another part will regress to cervical intraepithelial neoplasia grade 1 or less (CIN1-), and the last part will persist. Although the guidelines suggest that CIN2 patients with fertility requirements can be treated conservatively to minimize the risk of infertility and obstetric complications, most CIN2 patients undergo surgical treatment to prevent the progression of the disease, which will lead to over-treatment and unnecessary complications.

AIM OF REVIEW

The clinical outcome of CIN2 lesions is unpredictable and depends on histopathological examinations. Thus, it is necessary to identify the biomarkers differentiating regression lesions from progression lesions, which is conducive to supporting individualised treatment. The natural history of CIN2 is commonly regulated by the interaction of human papillomavirus (HPV) viral factors (HPV genotype and HPV methylation), host factors (p16/Ki-67 status, host gene methylation effects, human leukocyte antigen subtypes and immune microenvironment) and other factors (vaginal microbiota).

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review summarized the biomarkers predicting the spontaneous regression of CIN2, which correlated with HPV infection, the (epi)genetic change of host genes and microenvironment change. However, potential biomarkers must be validated with prospective cohort studies, which should be conducted with expanded enrollment, a longer observational period and the tracking of more patients.

Immunogenetic Determinants of Susceptibility to Head and Neck Cancer in the Million Veteran Program Cohort

Increasing rates of human papillomavirus (HPV)-driven oropharyngeal cancer (OPC) have largely offset declines in tobacco-associated head and neck squamous cell carcinoma (HNSCC) at non-OPC sites. Host immunity is an important modulator of HPV infection, persistence, and clearance, and also of immune evasion in both virally- and nonvirally-driven cancers. However, the association between collective known cancer-related immune gene variants and HNSCC susceptibility has not been fully characterized. Here, we conducted a genetic association study in the multiethnic Veterans Affairs Million Veteran Program cohort, evaluating 16,050 variants in 1,576 immune genes in 4,012 HNSCC cases (OPC = 1,823; non-OPC = 2,189) and 16,048 matched controls. Significant polymorphisms were further examined in a non-Hispanic white (NHW) validation cohort (OPC = 1,206; non-OPC = 955; controls = 4,507). For overall HNSCC susceptibility in NHWs, we discovered and validated a novel 9q31.1 SMC2 association and replicated the known 6p21.32 HLA-DQ-DR association. Six loci/genes for overall HNSCC susceptibility were selectively enriched in African-Americans (6p21.32 HLA-G, 9q21.33 GAS1, 11q12.2 CD6, 11q23.2 NCAM1/CD56, 17p13.1 CD68, 18q22.2 SOCS6); all 6 genes function in antigen-presenting regulation and T-cell activation. Two additional loci (10q26 DMBT1, 15q22.2 TPM1) were uncovered for non-OPC susceptibility, and three loci (11q24 CRTAM, 16q21 CDH5, 18q12.1 CDH2) were identified for HPV-positive OPC susceptibility. This study underscores the role of immune gene variants in modulating susceptibility for both HPV-driven and non-HPV-driven HNSCC. Additional large studies, particularly in racially diverse populations, are needed to further validate the associations and to help elucidate other potential immune factors and mechanisms that may underlie HNSCC risk.

SIGNIFICANCE

Several inherited variations in immune system genes are significantly associated with susceptibility to head and neck cancer, which could help improve personalized cancer risk estimates.

Regional differences in human papillomavirus type 52 prevalence among Japanese women with cervical intraepithelial neoplasia†

Although geographical differences in the distribution of human papillomavirus genotypes have been observed worldwide, no studies have reported on national differences in the prevalence of human papillomavirus types in Japan. Here, we report a cross-sectional study to explore regional differences in the prevalence of human papillomavirus types among Japanese women with cervical intraepithelial neoplasia or invasive cervical cancer. Using human papillomavirus genotyping data from the nationwide prospective study on human papillomavirus vaccine effectiveness, we compared the frequency of detection of 15 high-risk and two low-risk human papillomavirus types in each disease category between the women who visited hospitals located in eastern Japan and those who visited hospitals located in western Japan. The risk of cervical intraepithelial neoplasia progression was assessed by calculating a prevalence ratio of each human papillomavirus type for cervical intraepithelial neoplasia grade 2/3 versus grade 1. Among the human papillomavirus types studied, human papillomavirus 52 was detected significantly more frequently in western hospitals than in eastern hospitals in cervical intraepithelial neoplasia grade 1 patients, but was less frequent in cervical intraepithelial neoplasia grade 2/3. The prevalence of particular human papillomavirus types was not significantly different between patients in hospitals in eastern Japan and those in hospitals in western Japan for invasive cervical cancer. In both eastern and western hospitals, a higher risk of cervical intraepithelial neoplasia progression was observed in patients infected with human papillomavirus 16, 31 or 58. In contrast, there was a significantly higher prevalence of human papillomavirus 52 infection in women with cervical intraepithelial neoplasia grade 2/3 than in those with cervical intraepithelial neoplasia grade 1 in eastern hospitals (prevalence ratio, 1.93; 95% confidence interval, 1.48-2.58), but not in western hospitals (prevalence ratio, 1.03; 95% confidence interval, 0.83-1.30). Regional differences of human papillomavirus 52 prevalence in cervical intraepithelial neoplasia lesions may exist and emphasize the importance of continuous monitoring of human papillomavirus type prevalence throughout the country in order to accurately assess the efficacy of human papillomavirus vaccines.

Inside the pocket: Critical elements of HLA-mediated susceptibility to cervical precancerous lesions

Human papillomavirus (HPV) infection is a necessary cause for cervical cancer (CC), but it also depends on genetic factors, such as HLA polymorphism. However, few reports addressed the role of amino acids residues at the HLA peptide-binding cleft in HPV-related cervical disease. Therefore, we aimed to investigate the association between HLA-B, HLA-C, and HLA-DRB1 polymorphism and amino acid residues composing the pockets of the peptide-binding cleft of the respective polypeptide chains with cervical intraepithelial neoplasia (CIN II/III). HLA typing was performed by PCR-SSOP in 184 women with CIN II/III and 174 controls from South Brazil. Associations were estimated by multivariate logistic regression. FDR test was performed to correct the p-value for multiple comparisons. HLA-DRB1*13:01 was associated with protection against CIN II/III, while HLA-C*03:04 was associated with susceptibility. The amino acid residues isoleucine, tyrosine, and leucine at positions 95, 116, and 163 of HLA-C, respectively, were associated with CIN II/III susceptibility. In contrast, serine at positions 11 and 13 of HLA-DRB1 was associated with protection against the disease. Our results confirm previously reported associations between HLA and cervical diseases caused by HPV and suggest a role for amino acid residues at different positions of HLA-C and HLA-DRB1 in CIN II/III. This finding may be further explored to better understand the genetic risk and the influence of immune response to CC development.

Fine Mapping of the Major Histocompatibility Complex Region and Association of the HLA-B*52:01 Allele With Cervical Cancer in Japanese Women

IMPORTANCE

Understanding the genetic contribution of the major histocompatibility complex (MHC) region to the risk of cervical cancer (CC) will help understand how immune responses to infection with human papillomaviruses are associated with CC.

OBJECTIVE

To determine whether the HLA-B*52:01 allele is associated with CC in Japanese women.

DESIGN, SETTING, AND PARTICIPANTS

This was a multicenter genetic association study. Genotype and phenotype data were obtained from BioBank Japan Project. Additional patients with CC were enrolled from the Aichi Cancer Center Research Institute. An MHC fine-mapping study was conducted on CC risk in the Japanese population by applying a human leukocyte antigen (HLA) imputation method to the large-scale CC genome-wide association study data of using the Japanese population-specific HLA reference panel. Participants included 540 women in BioBank Japan Project with CC or 39 829 women without gynecologic diseases, malignant neoplasms, and MHC-related diseases as controls. An additional 168 patients with CC were recruited from Aichi Cancer Center Research Institute. Histopathological subtypes and clinical stages were not considered. Participants with low genotype call rate, closely related participants, and outliers in the principal component analysis were excluded. Data analysis was performed from August 2018 to January 2020.

MAIN OUTCOMES AND MEASURES

Loci within the MHC region associated with CC risk, and the direction and size of association.

RESULTS

A total of 704 CC cases and 39 556 controls were analyzed. All participants were Japanese women with a median (range) age of 67 (18 to 100) years. One of the class I HLA alleles of HLA-B*52:01 was significantly associated with CC risk (odds ratio, 1.60; 95% CI, 1.38-1.86; P = 7.4 × 10-10). Allele frequency spectra of HLA-B*52:01 are heterogeneous among worldwide populations with high frequency in Japanese populations (0.109 in controls), suggesting its population-specific risk associated with CC. The conditional analysis suggested that HLA-B*52:01 could explain most of the MHC risk associated with CC because no other HLA alleles remained significant after conditioning on the HLA-B*52:01. The HLA amino acid residue-based analysis suggested that HLA-B p.Tyr171His located in the peptide-binding groove was associated with the most significant CC risk (odds ratio, 1.47; 95% CI, 1.30-1.66; P = 1.2 × 10-9).

CONCLUSIONS AND RELEVANCE

The results of this study contribute to understanding of the genetic background of CC. The results suggest that immune responses mediated by class I HLA molecules are associated with susceptibility to CC.

The Host-Microbe Interplay in Human Papillomavirus-Induced Carcinogenesis

Every year nearly half a million new cases of cervix cancer are diagnosed worldwide, making this malignancy the fourth commonest cancer in women. In 2018, more than 270,000 women died of cervix cancer globally with 85% of them being from developing countries. The majority of these cancers are caused by the infection with carcinogenic strains of human papillomavirus (HPV), which is also causally implicated in the development of other malignancies, including cancer of the anus, penis cancer and head and neck cancer. HPV is by far the most common sexually transmitted infection worldwide, however, most infected people do not develop cancer and do not even have a persistent infection. The development of highly effective HPV vaccines against most common high-risk HPV strains is a great medical achievement of the 21st century that could prevent up to 90% of cervix cancers. In this article, we review the current understanding of the balanced virus-host interaction that can lead to either virus elimination or the establishment of persistent infection and ultimately malignant transformation. We also highlight the influence of certain factors inherent to the host, including the immune status, genetic variants and the coexistence of other microbe infections and microbiome composition in the dynamic of HPV infection induced carcinogenesis.

From HPV Infection to Lesion Progression: The Role of HLA Alleles and Host Immunity

Persistent high-risk human papillomavirus (HPV) infection has been associated with increased risk for cervical precancerous lesions and cancer. The host's genetic variability is known to play a role in the development of cervical cancer. The human leukocyte antigen (HLA) genes are highly polymorphic and have shown to be important risk determinants of HPV infection persistence and disease progression. HLA class I and II cell surface molecules regulate the host's immune system by presenting HPV-derived peptides to T-cells. The activation of T-cell response may vary depending on the HLA allele polymorphism. The engagement of the T-cell receptor with the HPV peptide-HLA complex to create an active costimulatory signal is essential for the activation of the T-cell response. Functional peptide presentation by both HLA class I and II molecules is needed to activate efficient helper and effector T-cell responses in HPV infection recognition and clearance. Some of these HLA risk alleles could also be used as preventive tools in the detection of HPV-induced cervical lesions and cancer. These HLA alleles, together with HPV vaccines, could potentially offer possible solutions for reducing HPV-induced cervical cancer as well as other HPV-related cancers.

Distribution of Human Papillomavirus Genotype in Anal Condyloma Acuminatum Among Japanese Men: The Higher Prevalence of High Risk Human Papillomavirus in Men Who Have Sex with Men with HIV Infection

Human papillomavirus (HPV) infection is known to cause anal condyloma acuminatum (CA) and squamous cell carcinoma. Men who have sex with men (MSM) with HIV infection are frequently co-infected with HPV, especially high risk HPV (HR-HPV) that causes anal squamous cell carcinoma. However, there are few reports of HPV genotype studies in anal lesion of Japanese men. We tried to estimate the distribution of HPV genotypes in anal CA tissue specimens from the Japanese men to elucidate the risk of anal cancer. A total of 62 patients who had anal CA surgically excised were enrolled. They included 27 HIV-positive MSM, 18 HIV-negative MSM, 1 HIV-positive man who have sex with women (MSW), and 16 HIV-negative MSW. HPV genotypes in anal CA tissue were determined by the polymerase chain reaction technique with reverse line blot hybridization. HR-HPV was detected in 45.2% of the CA tissue specimens and high grade squamous intraepithelial lesion (HSIL) was observed in 15.3%. Moreover, the prevalence of HR-HPV in the HIV-positive MSM (70.4%) was higher than the HIV-negative MSM (33.3%, p = .0311) or the HIV-negative MSW (18.8%, p = .0016). The conditional logistic regression analysis suggested HIV positivity as the primary risk factor for the HR-HPV infection in CA. In addition, HSIL was detected in higher frequency in CA tissues from HIV-positive MSM (25.9%) than HIV-negative MSW (0.0%, p = .0346). HR-HPV and HSIL were frequently detected in anal CA tissues from Japanese MSM patients with HIV infection, suggesting the necessity of surveillance for this population.

A functional polymorphism in the NKG2D gene modulates NK-cell cytotoxicity and is associated with susceptibility to Human Papilloma Virus-related cancers

Human papillomavirus (HPV) is the most common sexually transmitted agent worldwide and is etiologically linked to several cancers, including cervical and genital cancers. NKG2D, an activating receptor expressed by NK cells, plays an important role in cancer immune-surveillance. We analyzed the impact of a NKG2D gene variant, rs1049174, on the incidence of HPV-related cancers in Vietnamese patients and utilized various molecular approaches to elucidate the mechanisms of NKG2D receptor regulation by rs1049174. In a group of 123 patients with HPV+ anogenital cancers, the low cytotoxicity allele LNK was significantly associated with increased cancer susceptibility (p = 0.016). Similar results were also observed in a group of 153 women with cervical cancer (p = 0.05). In functional studies, NK cells from individuals with LNK genotype showed a lower NKG2D expression and displayed less efficient NKG2D-mediated functions than NK cells with HNK genotype. Notably, the rs1049174 variant occurs within a targeting site for miR-1245, a negative regulator of NKG2D expression. Compared with the higher cytotoxicity allele HNK, the LNK allele was more efficiently targeted by miR-1245 and thus determined lower NKG2D expression in NK cells with the LNK genotype. The NKG2D variants may influence cancer immunosurveillance and thus determine susceptibility to various malignancies, including HPV-induced cancers.