[Association between human leukocyte antigen and nasopharyngeal-carcinoma].

Nasopharyngeal carcinoma (NPC) is characterized by its distinct racial and geographical distribution with a multifactorial etiology. It has been well accepted that NPC is related to Epstein-Barr(EB) virus infection but environmental and genetics factors also play critical roles. Among host genetic markers associated with NPC, the highly variable class I human leukocyte antigen (HLA) genes on chromosome 6 (6p21.3) have shown a strong and consistent association with NPC risk. As the consequence of new generation DNA sequencing technologies used in HLA genotyping, the number of the reported HLA new alleles is dramaticllyincreasing, and more full length sequences of HLA alleles have been reported. The significant association between HLA genes and NPC has been identifiedin a series of studies, including HLA association study, linkage disequilibrium study for microsatellite markers, and genome wide association study. In this review, we summarize association studies between HLA and NPC to evaluate the role of genetic polymorphisms in NPC development and illustrate the new clues of HLA association for deepexploration.

LMP2-DC Vaccine Elicits Specific EBV-LMP2 Response to Effectively Improve Immunotherapy in Patients with Nasopharyngeal Cancer.

OBJECTIVE: To evaluate the safety and effectiveness of a vaccine based on latent membrane protein 2 (LMP2) modified dendritic cells (DCs) that boosts specific responses of cytotoxic T lymphocytes (CTLs) to LMP2 before and after intradermal injection in patients with nasopharyngeal carcinoma (NPC). METHODS: DCs were derived from peripheral blood monocytes of patients with NPC. We prepared LMP2-DCs infected by recombinant adenovirus vector expressing LMP2 (rAd-LMP2). NPC patients were immunized with 2 × 10 5 LMP2-DCs by intradermal injection at week 0 and after the second and fourth weeks. Specific responses to LMP2 were detected by enzyme-linked immunospot (ELISPOT) assay at week 0 and at the fifth and eighth weeks. Local clinicians performed the follow-up and tracking of patients. RESULTS: We demonstrated that DCs derived from monocytes displayed typical DC morphologies; the expression of LMP2 in the LMP2-DCs vaccine was confirmed by immunocytochemical assay. Twenty-nine patients with NPC were enrolled in this clinical trial. The LMP2-DCs vaccine was well tolerated in all of the patients. Boosted responses to LMP2 peptide sub-pools were observed in 18 of the 29 patients with NPC. The follow-up data of 29 immunized patients from April, 2010 to April 2015 indicated a five-year survival rate of 94.4% in responders and 45.5% in non-responders. CONCLUSION: In this pilot study, we demonstrated that the LMP2-DCs vaccine is safe and effective in patients with NPC. Specific CTLs responses to LMP2 play a certain role in controlling and preventing the recurrence and metastasis of NPC, which warrants further clinical testing.

Infection and integration of high-risk human papillomavirus in HPV-associated cancer cells.

High-risk human papillomaviruses (HPV) have been associated with many human cancers in clinical studies. Integration of HPV into the human genome is a suspected etiological factor in the induction of some HPV-associated cancers. The characteristics of HPV integration in certain HPV-integrated cancer cells remain unclear. In this study, ten HPV-associated carcinoma cell lines were evaluated for the presence, genotype, and integration status of HPV by nested polymerase chain reaction. The HPV genome did not insert in the genome of a mammary cancer cell line (MCF7), adrenal neuroblastoma cell line (NH-6), or three esophageal carcinoma cell lines (KYSE150, KYSE450 and KYSE140). HPV type 18 DNA did infect cell lines of tongue cancer (Tca83), hepatocellular carcinoma (Hep G2), and lung carcinoma (A549), but the HPV type 18 genes were not transcribed into mRNA. However, HPV type 18 integrated into the genomes of the esophageal carcinoma cell lines EC9706 and EC109, and the integration sites for both cell lines were in loci 8q24, which is a gene desert area adjacent to fragile sites. We speculate that HPV transcripts are more likely to integrate near highly susceptible fragile sites. This study suggests that HPV integration is still a significant issue that needs to be fully examined and can possibly be used as individualized biomarkers for the early diagnosis of HPV-related cancers.

[Research progress on hereditary fibrinogen abnormalities].

As the most abundant component of coagulation system, fibrinogen not only takes part in clotting, but also works as one of acute phase proteins, which participates in many physiological and pathophysiological processes. Studies of fibrinogen abnormalities contribute to understand the molecular basis of disorders of fibrinogen protein function and metabolism, caused mainly by gene mutation, commonly associated with bleeding, thrombophilia, or both. Diseases affecting fibrinogen could be classified to the acquired or inherited disease. In this review, the research progress on the molecular basis, possible action mechanism of the hereditary fibrinogen abnormalities and its clinical research are summarized.

Diagnostic significance of combined detection of Epstein-Barr virus antibodies, VCA/IgA, EA/IgA, Rta/IgG and EBNA1/IgA for nasopharyngeal carcinoma.

The objective of this study was to investigate the diagnostic significance of EBV antibody combined detection for nasopharyngeal carcinoma (NPC) in a high incidence region of southern China. Two hundred and eleven untreated NPC patients, 203 non-NPC ENT patients, and 210 healthy controls were recruited for the study. The titers of VCA/IgA and EA/IgA were assessed by immunoenzyme assay, and the levels of Rta/IgG and EBNA1/IgA were determined by enzyme-linked immunosorbent assay. The levels of VCA/IgA, EA/IgA, Rta/IgG and EBNA1/ IgA demonstrated no association with gender or age (p>0.05). The receiver operating characteristic curve and the area under the curve were used to evaluate the diagnostic value. The sensitivity of VCA/IgA (98.1%) and the specificity of EA/IgA (98.5%) were the highest. When a logistic regression model was used to combine the results from multiple antibodies to increase the accuracy, the combination of VCA/IgA+Rta/IgG, whose area under the curve was 0.99, had the highest diagnostic efficiency, and its sensitivity, specificity and Youden index were 94.8%, 98.0% and 0.93 respectively. The data suggest that the combination of VCA/IgA+Rta/IgG may be most suitable for NPC serodiagnosis.

[Prognostic significance of serum anti-Epstein-Barr virus antibodies in nasopharyngeal carcinoma].

OBJECTIVE: This study was aimed to investigate the association between serum against Epstein-Barr virus (EBV) antibodies levels and nasopharyngeal carcinoma (NPC) patients' prognosis. METHODS: Blood samples from 140 primary NPC patients without metastasis were collected before and after treatment. The titers of VCA/IgA and EA/IgA were detected by immunoenzyme assay, and the levels of NA1/IgA and Rta/IgG were detected by enzyme-linked immunosorbent assay (ELISA). All patients received consequent follow-up and long-term efficacy and survival assessment. RESULTS: Post-treatment serum levels of VCA/IgA, EA/IgA, NA1/IgA and Rta/IgG in NPC patients significantly decreased than those before treatment, while had significantly higher than those in control individuals (P < 0.05). Patients in remission had significantly lower pre-treatment serum levels of VCA/IgA and EA/IgA than patients with progression (P < 0.05). None of serum levels of VCA/IgA, EA/IgA, NA1/IgA and Rta/IgG was associated with the 3-year overall survival (P > 0.05). The progression-free survivals were significantly lower in patients with higher pre-treatment VCA/IgA (> or = 1 : 320) and EA/IgA (> or = 1:80) levels than in those with lower VCA/IgA ( < 1 : 320) and EA/IgA (< 1 : 80) levels, respectively (61.8% vs. 86.5% , 61.3% vs. 86.5%, P < 0.001). Cox regression model analysis demonstrated that pre-treatment serum VCA/IgA level was an independent risk factor for progression-free survival (HR = 3.80, P = 0.001). CONCLUSION: Anti-EBV VCA/IgA and EA/IgA might provide information regarding the prognosis of NPC patients.

[Relationship between HLA-A, B alleles and red blood cell parameters of patients with --(SEA/αα) subtype of α(0)-thalassemia of Han ethnic population of Wuzhou city].

This study was purposed to investigate the relationship between HLA-A, B allele polymorphisms and red blood cell parameters of patients with --(SEA/αα) subtype of α(0)-thalassemia in Han ethnic population of Wuzhou city. The HLA genetic polymorphisms were determined by polymerase chain reaction-sequence-based typing (PCR-SBT) in 57 patients with --(SEA/αα) subtype of α(0)-thalassemia of Han ethnic population in Wuzhou city, Guangxi province, China. Mean corpuscular volume (MCV), hemoglobin (Hb), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were detected by automatic blood analyzer system. HbA2 were detected by electrophoretic method. The statistical analysis was performed by ordinal polytomous logistic regression. The results showed that Hb and HbA2 levels were significantly lower in patients positive for HLA-A*33:03, B*15:01 or B*55:02, and were significantly higher in patients positive for B*15:02 (P < 0.05). It is concluded that several HLA alleles may be associated with Hb level of --(SEA/αα) subtype of α(0)-thalassemia of Han ethnic population in Wuzhou city. This result has the value for understanding phenotype-genotype relationships in thalassemia.

[Evaluation of computational methods for HLA three loci haplotype by compare with family-based data].

OBJECTIVE: We evaluated the accuracy and efficiency of computational inference methods for haplotype on estimate HLA-A-B-C haplotype frequencies by compared with the haplotypes manually defined in a family-base dataset. METHODS: 558 individuals with pedigree information were selected, and their haplotyps were compared with the data obtained by the following three method: the Expectation-Maximization (EM) and Excoffier-Laval-Balding (ELB)algorithms using the AELEQUIN software, and the SAS/Genetics PROC HAPLOTYPE method. RESULTS: After performing the SAS/Genetics method, and the Expectation-Maximization (EM) and Excoffier-Laval-Balding (ELB) algorithms using the AELEQUIN software, 248, 247, and 238 different haplotypes were obtained respectively. The accuracy rates of these three methods were 88.5%, 89.1%, and 90.3% respectively. There are no significant different in the accuracy and estimated haplotype frequency comparisons among any two of these computational inference methods. CONCLUSION: High accuracy haplotype frequency estimate rates could be obtained by these three computational inference methods, and there are no significant difference in the comparison of haplotypes estimated by SAS/Genetics, the EM and ELB algorithms using the AELEQUIN software. However, ELB algorithm shows better performance than EM algorithm and SAS/Genetics PROC HAPLOTYPE method for haplotype frequencies estimation in general.

[Molecular detection and haematological analysis of heterozygotes in beta-thalassemia combining deletional alpha-thalassemia].

This study was aimed to investigate the prevalence and genotype distribution of heterozygotes in beta-thalassemia combining deletional alpha-thalassemia by using molecular detection and haematological methods. Three common deletions of alpha-thalassemia were detected by using gap-PCR. The mutations of beta-thalassemia were identified by using PCR with reverse dot blot hybridization. The routine analysis of blood cells was carried out. The results indicated that 15 cases from the 81 beta-thalassemia traits were found to be the compound heterozygosity for beta-thalassemia and alpha-thalassemia with 9 different types of gene defects with 18.52% detection rate. There were 6 cases (7.41%) of beta-thalassemia heterozygote combining alpha-thalassemia-1 gene (--(SEA)/alphaalpha), 8 cases (9.88%) combining with alpha-thalassemia-2 gene including 6 (7.41%) right ward deletion (-alpha(3.7)/alphaalpha) and 2 (2.47%) left ward deletion (-alpha(4.2)/alphaalpha), and 1 case (1.23%) combining deletional HbH gene (--(SEA)/-alpha(3.7)). No significant differences were found between beta-thalassemia heterozygotes combining deletional alpha-thalassemia and pure beta-thalassemia in all RBC parameters. It is concluded that the incidence of beta-thalassemia heterozygotes combining with deletional alpha-thalassemia is frequent in Wuzhou city. The hematological analysis can not give specificity for diagnosing these dual heterozygotes. Gap-PCR as a routine method for thalassemia screening has the advantages in reducing the possibility of failing to detect the combining heterozygosity for beta-thalassemia and alpha-thalassemia. It is more useful for genetic counselling and prenatal diagnosis of this disease.

[Sequence analysis of the deletion and mutation in carboxy terminal region of the Epstein-Barr virus latent membrane protein 1 derived from nasopharyngeal carcinoma patients].

BACKGROUND: To study the deletion and mutation in carboxy terminal region of LMP1 gene derived from nasopharyngeal carcinoma (NPC) in Guangdong and Guangxi, the high risk areas of nasopharyngeal carcinoma in China. METHODS: LMP1 gene carboxy terminal region was amplified from nasopharyngeal carcinoma tissues by PCR, and then cloned and sequenced. RESULTS: Of the 20 cases, 17 were LMP1 positive. In all positive cases, only 1 case did not show deletion. Four positive cases were chosen for DNA sequencing, The rusult showed that all the four cases had mutation and the 30bp deletion. CONCLUSIONS: High frequency of deletion and mutation in LMP1 gene of nasopharyngeal carcinoma tissues was found in Guangdong and Guangxi. Whether it related to the high incidence of NPC should be further studied.