[Relationship between selenium and the risk for oral cancer: a case-control study].

Objective: To explore the relationship between selenium and the risk for oral cancer. Methods: We performed a case-control study in 325 cases of newly diagnosed primary oral cancer from the First Affiliated Hospital of Fujian Medical University and 650 controls from the same hospital and community. Unconditional logistic regression and stratification analyses were used to explore the association between selenium and oral cancer. Adjusted OR and corresponding 95%CI were calculated. The analyses on multiple interactions between selenium and smoking or drinking status, and fruit or fish intake frequencies were conducted. Results: The level of serum selenium was 112.42 (80.98-145.06) µg/L in the case group, which was lower than 164.85 (144.44-188.53) µg/L in control group, the difference was statistical significant (P<0.01). There was a negative correlation between serum selenium level and the risk for oral cancer regardless of smoking and drinking status, and fruits and fish intake frequencies (P<0.05). There were multiple interactions between serum selenium level and smoking or drinking status, and fruit and fish intakes. Conclusions: The high level of serum selenium is a protective factor for the incidence of oral cancer, and serum selenium has multiple interactions with smoking or drinking status, and fruit and fish intakes. Therefore, reducing tobacco use and alcohol consumption and increasing the intakes of fruit and fish can reduce the risk for oral cancer to some extent.

[Association of single nucleotide polymorphisms of TBX5 gene and environmental exposure index with susceptibility to oral cancer].

Objective: To explore the association of TBX5 polymorphisms and environmental exposure index with susceptibility to oral cancer. Methods: A case-control study was conducted to collect 300 oral cancer patients hospitalized in the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Fujian Medical University from September 2010 to December 2016. A total of 445 non-tumor patients were selected as the control group. Questionnaires were used to collect the information of all subjects and 5 ml peripheral blood was collected to detect single nucleotide polymorphisms (SNPs) of the rs10492336 locus of TBX5 gene. According to the environmental exposure index score, subjects were divided into two groups, low risk group (0-2.31) and high risk group (2.32-11.76). To analyze the association of TBX5 gene rs10492336 SNPs, environmental exposure index and oral cancer and its interactions. Results: The age of all subjects in the case group and control group were (56.19±13.10) years and (54.56±12.48) years old. Compared with CC genotype, the OR (95%CI) values of the co-dominant genetic model AC genotype and the dominant genetic model AC+AA genotype were 0.69 (0.49-0.98) and 0.70 (0.51-0.97), respectively. Compared with the low risk group, the OR (95%CI) risk of oral cancer in the high risk group was 3.72 (2.55-5.43). The results of gene-environment interaction analysis showed that compared with the group with CC genotype and high risk of environmental exposure index, the OR (95%CI) value of oral cancer in the group with AC+AA genotype and low risk of environmental exposure index was 0.18(0.10-0.31). Furthermore there was a multiplicative interaction between rs10492336 SNPs and environmental exposure index (ß=-0.405, P<0.001). Conclusion: This study suggests that the TBX5 gene rs10492336 SNPs and environmental exposure index were associated with oral cancer. And there was a multiplication interaction between rs10492336 SNPs and environmental exposure index.

High-resolution HLA-A, -B and -DRB1 allele and haplotype frequencies in 7823 Han marrow donors of Liaoning province, China.

BACKGROUND: The human leukocyte antigen (HLA) system is the most polymorphic gene cluster in humans. High-resolution donor-recipient matching for HLA genes improves patient survival after unrelated hematopoietic stem cell transplantation. MATERIALS AND METHODS: In this study, we analyzed the high-resolution allele and haplotype frequencies at the HLA-A, -B and -DRB1 loci in the Liaoning Han population and analyzed its relationships with other populations. RESULTS: The 3 most frequent alleles at the HLA-A, -B and -DRB1 loci were A*24:02, A*02:01:01G, A*11:01; B*13:02, B*46:01, B*40:01:01G; DRB1*09:01, DRB1*15:01 and DRB1*07:01, respectively. The most frequent 2-locus haplotypes were A*30:01-B*13:02 and B*13:02-DRB1*07:01. A*30:01-B*13:02-DRB1*07:01 was determined to be the predominant 3-locus haplotype. Hot maps and multiple correspondence analyses based on the frequencies of HLA specificities, which allow statistical visualization of dependent and independent relationships among variables, indicate that the Liaoning Han population is closely related to Northern populations of China and shows relative close relationships with Asian populations. CONCLUSION: These data will provide an outline of the HLA characteristics of healthy individuals in our region and help bone marrow transplantation patients find suitable HLA-matched donors.

HLA-A, HLA-B, HLA-DRB1 allele and haplotype frequencies of 14,529 Chinese Han bone marrow donors living in Dalian, China.

We investigated the allele and haplotype frequencies of HLA-A, HLA-B and HLA-DRB1 loci in Dalian Chinese Han population using blood samples of unrelated marrow donors who live in Dalian. The genetic relationship between Dalian and different regions worldwide was further explored based on HLA status of different populations. A total of 14,529 samples were genotyped at 2-digit level only by sequence-specific oligonucleotide and sequence-based typing methods. Allele frequencies of HLA-A, HLA-B and HLA-DRB1 were calculated by the direct counting method. Haplotype frequencies and linkage disequilibrium (LD) values were calculated by the maximum likelihood method. F(ST) values were calculated by allele frequency data of each locus. Phylogeny tree of Nei's DA genetic distances was constructed by the UPGMA method. HLA-A*02 was the most frequent allele at HLA-A locus followed by A*11 and A*24. Alleles at HLA-B locus ranked in decreasing order by frequency were B*40, B*15 and B*13. The three highest frequency alleles were DRB1*15, DRB1*09 and DRB1*12 at HLA-DRB1 locus. A*30-B*13-DRB1*07 was the most frequent three-locus haplotype. For the population relationships, Dalian had a relative close genetic relationship with Liaoning and Yantai-Weihai and a relative distant genetic relationship with Australia. The information obtained in this study may provide useful information for anthropological studies, for disease-association studies and helping bone marrow transplantation patients to search HLA-matched donors.

Stabilisation of p53 enhances reovirus-induced apoptosis and virus spread through p53-dependent NF-κB activation.

BACKGROUND: Naturally oncolytic reovirus preferentially kills cancer cells, making it a promising cancer therapeutic. Mutations in tumour suppressor p53 are prevalent in cancers, yet the role of p53 in reovirus oncolysis is relatively unexplored. METHODS: Human cancer cell lines were exposed to Nutlin-3a, reovirus or a combination of the two and cells were processed for reovirus titration, western blot, real-time PCR and apoptosis assay using Annexin V and 7-AAD staining. Confocal microscopy was used to determine translocation of the NF-κB p65 subunit. RESULTS: We show that despite similar reovirus replication in p53(+/+) and p53(-/-) cells, stabilisation of p53 by Nutlin-3a significantly enhanced reovirus-induced apoptosis and hence virus release and dissemination while having no direct effect on virus replication. Enhanced apoptosis by Nutlin-3a was not observed in p53(-/-) or p53 knockdown cells; however, increased expression of Bax and p21 are required. Moreover, elevated NF-κB activation in reovirus-infected cells following Nutlin-3a treatment was necessary for enhanced reovirus-induced apoptosis, as synergistic cytotoxicity was overcome by specific NF-κB inhibitors. CONCLUSION: Nutlin-3a treatment enhances reovirus-induced apoptosis and virus spread through p53-dependent NF-κB activation, and combination of reovirus and Nutlin-3a might represent an improved therapy against cancers harbouring wild-type p53.

Expression of GnTIII in a recombinant anti-CD20 CHO production cell line: Expression of antibodies with altered glycoforms leads to an increase in ADCC through higher affinity for FC gamma RIII.

The gene encoding the rat glycosylation enzyme beta1-4-N-acetylglucosaminyltransferase III (GnTIII) was cloned and coexpressed in a recombinant production Chinese hamster ovary (CHO) cell line expressing a chimeric mouse/human anti-CD20 IgG1 antibody. The new cell lines expressed high levels of antibody and have growth kinetics similar to that of the parent. Relative QPCR showed the cell lines to express varying levels of mRNA. High-performance liquid chromatography (HPLC) analysis showed the enzyme to have added bisecting N-acetylglucosamine (GlcNAc) residues in most (48% to 71%) of the N-linked oligosaccharides isolated from antibody preparations purified from the cell lines. In an ADCC assay the new antibody preparations promoted killing of CD20-positive target cells at approximately 10- to 20-fold lower concentrations than the parent. This activity was blocked using an anti-Fc gamma RIII antibody, supporting the role of Fc gamma RIII binding in this increase. In addition, cell binding assays showed the modified antibody bound better to Fc gamma RIII-expressing cells. The increase in ADCC activity is therefore likely due to an increased affinity of the modified antibody for the Fc gamma RIII receptor.

Human monoclonal antibodies isolated from spontaneous Epstein-Barr virus-transformed tumors of Hu-SPL-SCID mice and specific for fusion protein display broad neutralizing activity toward respiratory syncytial virus.

Two human monoclonal antibodies, RF-1 and RF-2, specifically recognize the fusion protein of the human respiratory syncytial virus (RSV). These were isolated from spontaneous tumors in SCID mice reconstituted with human splenocytes and boosted with fusion protein. The tumors consisted of Epstein-Barr virus-transformed human B cells in animals with antigen-specific antibody titers>105. The binding affinity of RF-1 and RF-2 to the fusion protein is 1010 and 109 M-1, respectively. The antibodies bind specifically to a conformational epitope of the fusion protein on RSV-infected HEp-2 cells. Both antibodies display virus-neutralizing properties in vitro at concentrations varying between 8 and 1000 ng/mL. Virus neutralization applies to a broad variety of wild and laboratory-adapted virus strains belonging to both virus types A and B. These antibodies are potential candidates for passive immunotherapy of severe RSV infections.

Comparison of in vivo plasma and peripheral blood mononuclear cell HIV-1 quasi-species to short-term tissue culture isolates: an analysis of tat and C2-V3 env regions.

OBJECTIVE: To determine whether the HIV-1 genomes that grow out in vitro from peripheral blood mononuclear cells (PBMC) better represent the in vivo quasi-species present in plasma or PBMC. RESULTS: For one patient (9606), PBMC culture represented more accurately the plasma rather than the in vivo PBMC quasi-species distribution, because a large number of tat-defective proviruses present in PBMC in vivo were not detected in plasma nor in the PBMC cultures. For a second patient (9605), PBMC culture was representative of both in vivo PBMC and plasma tat sequences, but selection of C2-V3 env sequences was observed in PBMC cultures compared with sequences present in both plasma and PBMC in vivo. This selection consisted of the absence in vitro of genomes with certain amino-acid substitutions at or near conserved glycosylation sites of the C2 region at positions 276 and 289. Site 276 has been reported to be important for viral infectivity, and these substitutions may therefore have affected infectivity. In the third patient (10095), selection of both tat and C2-V3 sequences was observed in culture as compared to plasma and PBMC in vivo. In contrast to the first two patients, this third patient contained V3 sequences in vivo that were predicted to impart syncytium induction and enhanced replication capacity. It was these sequences that grew out preferentially in vitro. CONCLUSION: This study suggests that short-term PBMC culture is representative of HIV-1 genomes present in PBMC and plasma in vivo to the degree that they are infectious.

Detection of plasma viremia in human immunodeficiency virus-infected individuals at all clinical stages.

Free virus (virus not present within cells) was detected in the plasma of all human immunodeficiency virus (HIV)-infected individuals studied. Plasma samples from asymptomatic individuals and individuals with HIV disease were tested. The levels of virus varied, but high virus titers correlated directly with HIV-related symptoms and low CD4+ lymphocyte counts. Effective detection of infectious virus depended on the use of an enzyme-linked immunosorbent assay for p24 core antigen and culture conditions in which plasma was added to mitogen-stimulated lymphocytes within 3 h of venipuncture. When there were delays in the time to culturing of plasma, neutralizing antibodies and perhaps other factors present in the plasma were found to reduce the efficiency of virus recovery. Plasma stored at -70 degrees C for several months maintained a stable level of free virus. These results suggest that measurement of HIV present in plasma under optimal conditions could be an efficient way of monitoring the clinical state of an individual and the effects of antiviral therapy.

Lack of detection of human immunodeficiency virus in persistently seronegative homosexual men with high or medium risks for infection.

Some studies have suggested that seronegative homosexual men who have practiced high-risk sexual behavior can carry the human immunodeficiency virus (HIV) in a silent state, detectable only by polymerase chain reaction (PCR) or selective viral culture. To assess this concept, blood specimens were studied from 59 homosexual men with recognized risk behaviors: unprotected anal receptive intercourse at least once and many lifetime sex partners. After extensive virologic studies and PCR analysis, only one virus-positive, antibody-negative individual was identified. These findings indicate that HIV virus-positive, seronegative individuals are rare.

CD8+ T cells from HIV-1-infected individuals inhibit acute infection by human and primate immunodeficiency viruses.

T lymphocytes expressing the CD8 surface antigen block HIV replication in CD4+ peripheral blood cells from HIV-infected individuals. We report here that CD4+ cells from HIV seronegative donors, when infected in vitro with HIV, also do not replicate virus when cocultured with CD8+ T cells from HIV-infected individuals. CD8+ cells from HIV-uninfected donors did not show this effect on virus replication. HLA-restriction of the antiviral response was not observed, and virus-containing cells were not eliminated from culture. The antiviral activity was broadly cross-reactive, as CD8+ cells from individuals infected only with HIV-1 suppressed the replication of diverse strains of HIV-1 and HIV-2, as well as the simian immunodeficiency virus. This ability of CD8+ cells to control HIV replication could play an important role in the maintenance of an asymptomatic state in HIV-infected individuals.

Long-term observation of baboons, rhesus monkeys, and chimpanzees inoculated with HIV and given periodic immunosuppressive treatment.

Baboons, rhesus monkeys, and chimpanzees were injected with the human immunodeficiency virus (HIV) and monitored for up to 4 years. Various immunosuppressive regimens were used during this time in attempts to induce development of the acquired immune deficiency syndrome (AIDS). No infectious virus was recovered or anti-HIV antibodies detected in the baboons and rhesus monkeys. Virus has been recovered from lymphocyte cultures of all five of the chimpanzees at intermittent periods following inoculation. The chimpanzees developed anti-HIV antibodies from 1 to 5 months after virus inoculation and had circulating antibodies that neutralized HIV. All the infected animals were capable of in vitro lymphocyte blastogenic responses to recombinant envelope and core HIV antigens. Despite immunosuppressive therapies and evidence of some immunologic abnormalities, none of the five chimpanzees has yet developed AIDS or a related disorder.

Patterns of antibody response in individuals infected with the human immunodeficiency virus.

Immunofluorescence and immunoblot assays were conducted on 488 sera from patients with AIDS and clinically healthy individuals at risk for infection by the human immunodeficiency virus. Of these, 360 contained antiviral antibodies, and nearly all reacted with the envelope precursor glycoprotein gp160. Sera from 103 individuals for whom a complete clinical history was available were evaluated in detail. Most sera recognized both the gp160 and the p55 gag precursor protein. Because these two antigens are found primarily in infected cells, the results suggest that this association makes them more immunogenic. A high prevalence of antibodies to the polymerase gene products (p65 and p31) and to a viral protein p48, which is not yet fully defined, was also noted. Many sera, particularly those from patients with Kaposi's sarcoma or Pneumocystis carinii pneumonia, lacked antibodies to both p25 and gp41. These antibody patterns could help predict the prognosis for virus-infected individuals.

Relation of oral hairy leukoplakia to infection with the human immunodeficiency virus and the risk of developing AIDS.

We investigated the relation of oral hairy leukoplakia (HL) to human immunodeficiency virus (HIV) infection and to the presence or development of AIDS. All 155 patients with HL seen in our clinic were immunosuppressed homosexual men. Of 101 serum samples obtained from patients in this group who did not have AIDS, 100 showed antibodies to HIV. HIV was recovered from peripheral blood mononuclear cells of 22 of 28 patients tested. Most serum samples examined by immunoblot assay reacted with the viral envelope and gag gene precursors gp160 and p55. Of the 155 patients, 12 had AIDS at the time of diagnosis, and the syndrome developed in an additional 43 patients in one to 31 months. Survival analysis showed that the probability of AIDS developing in patients with HL was 48% by 16 months and 83% by 31 months. We conclude that oral HL is highly predictive of the development of AIDS.

Absence of antibodies to the human immunodeficiency virus in sera from Africa prior to 1975.

Three different assays for detection of antibodies to the human immunodeficiency virus (HIV) were conducted on 677 sera obtained from 1964 to 1975 from male and female children and adults in Uganda and other countries in Africa. Several sera were collected from individuals with Kaposi sarcoma. No evidence of antibodies to the virus was noted up to 1975. These results strongly suggest that the emergence of HIV in Africa occurred relatively recently. Further studies are required to determine the geographic origin of the acquired immunodeficiency syndrome virus.

Altered natural killer and natural cytotoxic cellular activities in lpr mice.

Three strains of mice bearing the autosomal recessive lpr gene (MRL, C57BL/6, and C3H) that had spontaneously developed a lupus-like disease were studied sequentially for functional natural killer (NK) and natural cytotoxic (NC) cell activity. Natural killing was impaired in spleen and bone marrow cells from all the lpr strains, as well as from the congenic strain MRL--+/+, which develops a late onset lupus-like disease. The NK cell activity was found to be depleted as early as 2 months of age in all lpr strains, and decreased further with age. NK activity was augmentable by Poly I:C and interleukin 2 (IL-2), suggesting that the residual cells can respond to NK modulators. In contrast with NK cell activity, NC activity was not decreased in lpr mice but could be augmented by IL-3-rich supernatants. The spontaneous decrease in NK cell activity was associated with an increased autologous plaque-forming cell (APFC) response to bromelin-treated mouse red blood cells, which is produced primarily by B cells possessing the Ly-1 phenotype (Lyt-1+ B). When NK cell activity was increased by exogenous administration of Poly I:C, the APFC response diminished. Treatment of spleen cells with anti-asialo GM1 prior to Poly I:C treatment resulted in a decreased NK response but increased both APFC and Lyt-1+ B cells. The possible regulation of autoreactivity by NK cells is discussed.