Ranko Hirata

Human papillomavirus type 16 E6 variants and HLA class II alleles among Japanese women with cervical cancer

The enhanced oncogenicity of particular human papillomavirus type 16 (HPV16) E6 variants is population‐dependent, implying the involvement of additional genetic cofactors. This study was designed to investigate the association between E6 variants and human leukocyte antigen (HLA) polymorphism within a Japanese population. Fifty‐seven women with HPV16‐positive cervical cancer were analyzed for E6 sequence variation and its relationship to HLA class II alleles. Compared with local controls (n = 138) and published controls (n = 916), DRB1*1501 and DQB1*0602 frequencies were significantly increased among patients with HPV16 E6 prototype (n = 11). Additionally, DRB1*1502 was positively associated with a particular E6 variant designated D25E (n = 25), although we could not find a significant association between HLA class II alleles and L83V variants (n = 16). Our observations suggest that a specific match between E6 variant proteins and HLA types may contribute to HPV16‐related cervical carcinogenesis.

HLA class II DRB1*1302 allele protects against progression to cervical intraepithelial neoplasia grade 3: a multicenter prospective cohort study.

Objective Genetic variations in human leukocyte antigens (HLA) class II regions may influence the risk of cervical cancer by altering the efficiency of the immune responses to human papillomavirus antigens. This prospective study was designed to evaluate the effects of HLA class II alleles on the natural course of cervical precursor lesions. Methods We followed a total of 454 Japanese women with cytological low-grade squamous intraepithelial lesion (LSIL) and histological cervical intraepithelial neoplasia grades 1 to 2 (CIN1-CIN2). Patients were tested for HLA class II alleles and cervical human papillomavirus DNA at the time of entry and then monitored by cytology and colposcopy every 4 months for a mean follow-up of 39.0 months. We analyzed cumulative probabilities of cytological regression to at least 2 consecutive negative Papanicolaou tests and histological progression to biopsy-positive CIN3. Results During the follow-up period, 39 lesions progressed to CIN3, and 282 lesions regressed to normal cytology. Progression to CIN3 did not occur in DRB1*1302-positive women, and this protective effect of DRB1*1302 was statistically significant (P = 0.03). Low-grade squamous intraepithelial lesion regressed to normal cytology more quickly in DRB1*1302-positive women than in DRB1*1302-negative women (median time, 8.9 months vs 14.2 months), although the difference was not statistically significant (P = 0.16). The risk of LSIL persistence or progression to CIN3 within 5 years was not affected by any other HLA class II alleles. Conclusion By using a prospective study design, we demonstrated the protective effect of the DRB1*1302 allele against progression to CIN3 among Japanese women with LSIL.

Analysis of HLA‐DRB1*0901‐binding HPV‐16 E7 helper T cell epitope†

Aim:  This study sought to determine the human papillomavirus (HPV)‐16 E7 epitopes that would be presented by HLA‐DR molecules to CD4‐positive T cells in patients with cervical carcinoma.

Association of human leukocyte antigen and T cell message with human papillomavirus 16–positive cervical neoplasia in Japanese women

To investigate whether an association exists between human leukocyte antigen (HLA) haplotype and cervical neoplasia within the Japanese population, we analyzed the human papillomavirus (HPV) genotypes, the HLA class I specificities and class II alleles, and the T-cell responses in the lesions of patients with cervical neoplasia. Eighty-one patients, consisting of 62 cervical intraepithelial neoplasia (CIN) lesions and 19 invasive cervical cancers (ICC), were examined. The frequencies of HPV infection in the CIN I/II and CIN III/ICC groups were 68.0% (17/25) and 80.4% (45/56), respectively. All patients and 138 local Japanese controls were analyzed for HLA-A, HLA-B, HLA-DRB1, and HLA-DQB1. For major histocompatibility complex (MHC) class II HLA-DRB1 alleles, the frequency of DRB1*0901 was significantly elevated in HPV 16–positive CIN III/ICC patients compared with controls (59.3% versus 29.7%, P= 0.0031, OR = 3.44). Similarly for the HLA-DQB1 alleles, a significant increase in the DQB1*03032 frequency was observed in HPV 16–positive CIN III/ICC patients compared with controls (59.3% versus 28.3%, P= 0.0018, OR = 3.69). In the analysis of the T-cell responses in the lesions, Fas ligand was detected at a decreased frequency in HPV 16–positive CIN III/ICC patients with the HLA-DRB1*0901–DQB1*03032 haplotype. The presence of helper T cell–specific messenger RNAs in the cervical lesions supports an association among MHC class II, helper T cells, the immune response to HPV, and the development of cervical carcinoma. Accordingly, a specific MHC class II haplotype, DRB1*0901–DQB1*03032, may be a risk factor for cervical carcinoma in the Japanese population.

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

We investigated the role of human leukocyte antigen (HLA) class II alleles in multistage cervical carcinogenesis. Cross‐sectional analysis for HLA association with cervical cancer included 1253 Japanese women: normal cytology (NL, n = 341), cervical intraepithelial neoplasia grade 1 (CIN1, n = 505), CIN grade 2 or 3 (CIN2/3, n = 96), or invasive cervical cancer (ICC, n = 311). The HLA class II allele frequencies were compared by Fishers exact test or the χ2‐test. The Bonferroni adjustment corrected for multiple comparisons. Among the study subjects, 454 women with low‐grade squamous intraepithelial lesion cytology were prospectively monitored by cytology and colposcopy every 3–4 months to analyze cumulative risk of CIN3 within the next 10 years in relation to HLA class II alleles. HLA class II DRB1*1302 allele frequency was similar between women with NL (11.7%) and CIN1 (11.9%), but significantly decreased to 5.2% for CIN2/3 and 5.8% for ICC (P = 0.0003). Correction for multiple testing did not change this finding. In women with low‐grade squamous intraepithelial lesion cytology, the cumulative risk of CIN3 diagnosed within 10 years was significantly reduced among DRB1*1302‐positive women (3.2% vs. 23.7%, P = 0.03). In conclusion, the two different types of analysis in this single study showed the protective effect of the DRB1*1302 allele against progression from CIN1 to CIN2/3.

Two-Dimensional IEF Analysis of DR, DQ, and DP Molecules from DRW8-Carrying Haplotypes

HLA-DR, DQ, and DP molecules were isolated from eight HLA-DRw8 homozygous B-cell lines using the monoclonal antibodies (MAb) submitted to the 10th International Histocompatibility Workshop. These molecules were analyzed by two-dimensional IEF gel electrophoresis as previously described (1).

DR2 and DQw1 Molecules in Narcolepsy

Narcolepsy is a clinical disease entity characterized by excessive daytime sleepiness and cataplexy. The cause and genetic basis for the disease has been unknown until 1984, when an extraordinary association between HLA-DR2 and narcolepsy was reported (1,2). This association was confirmed to be complete by the HTC typing (Dw2) (3,4) and by molecular genetics (DQR2.6) (4,5) and was confined to a specific DR2-carrying haplotype, HLA-DR2-Dw2-DQw1 (6). We have isolated DR2 and DQw1 molecules from nine DR2-positive Japanese patients with narcolepsy using anti-DR and anti-DQw1 related monoclonal antibodies and analyzed them by one- and two-dimensional IEF gel electrophoresis. The results indicated that both DQw1 α and β chains focused identically among patients and DR2-Dw2-positive normals but clearly distinct from those of DR2-Dw12 normal Japanese. DR2 α and β chains were identical among patients and DR2-Dw12 as well ad DR2-Dw2 normals. A second DR2 β chain isolated from one DR2 homozygous patient was identical with those of normal DR2-Dw2 individuals but distinct from DR2-Dw12 normals. The data strongly suggest that both DR2 and DQw 1 molecules are identical among patients and normals.

Three Subtypes of DRw52 Molecules Among DR3, DR5, and DRw6 Haplotypes

In the HLA-DR subregion, two allelic series of DR molecules, DR1-DRw14 and DRw52–DRw53, have been recognized. DRw52 is supertypic to DR and is found in association with DR3, DR5, DRw6, and DRw8. We recently produced a monoclonal antibody PLM16 that strongly reacted with DR3, DR5, and DRw6 and thus showed the DRw52-like specificity. The antibody bound to a single DR 13 chain from DR5 and DRw6 haplotypes but two DR 13 chains from DR3 haplotype. These DR 13 chains carrying the DRw52-like determinant, i.e., DRw52 molecules. from cells of DR3, DR5, and DRw6 types were directly compared by one-dimensional IEFgel electrophoresis and immunoblotting methods. Three subtypes of DRw52 13 chains became evident; the most acidic type, DRw52a, was found in association with DR3, DRwil, DRw13, and DRw14; an intermediate one, DRw52b, with DRw13; and the most basic one, DRw52c, with DRw12 (1).