A genetic variant of FcγRIIIa is strongly associatedwith humoral immunity to cyclin B1 in African American patients with prostate cancer

Autoantibodies in cancer: a systematic review of their clinical role in the most prevalent cancers

Although blood autoantibodies were initially associated with autoimmune diseases, multiple evidence have been accumulated showing their presence in many types of cancer. This has opened their use in clinics, since cancer autoantibodies might be useful for early detection, prognosis, and monitoring of cancer patients. In this review, we discuss the different techniques available for their discovery and validation. Additionally, we discuss here in detail those autoantibody panels verified in at least two different reports that should be more likely to be specific of each of the four most incident cancers. We also report the recent developed kits for breast and lung cancer detection mostly based on autoantibodies and the identification of novel therapeutic targets because of the screening of the cancer humoral immune response. Finally, we discuss unsolved issues that still need to be addressed for the implementation of cancer autoantibodies in clinical routine for cancer diagnosis, prognosis, and/or monitoring.

Immune mechanisms behind prostate cancer in men of African ancestry: A review

BACKGROUND

Men of African ancestry (AA) with prostate cancer suffer from worse outcomes. However, a recent analysis of patients treated with the dendritic cell vaccine sipuleucel-T for prostate cancer suggested that AA patients could have improved outcomes relative to whites.

METHODS

We conducted a focused literature review of Medline-indexed articles and clinical trials listed on clinicaltrials.gov.

RESULTS

We identify several studies pointing to enrichment of inflammatory cellular infiltrates and cytokine signaling among AA patients with prostate cancer. We outline potential genomic and transcriptomic alterations that may contribute to immunogenicity. Last, we investigate differences in host immunity and vaccine responsiveness that may be enhanced in AA patients.

CONCLUSIONS

AA patients with prostate cancer may be enriched for an immunogenic phenotype. Dedicated studies are needed to better understand the immune mechanisms that contribute to existing cancer disparities and test immune-based therapies in this population.

Polymorphisms of CCNB1 Associated With the Clinical Outcomes of Platinum-Based Chemotherapy in Chinese NSCLC Patients

As a crucial cell cycle regulator and G2/M phase promotor, CCNB1 played an essential role in progression of chemotherapy related cell death. Platinum-based chemotherapy is still the first-line chemotherapy regimen for most advanced NSCLC patients. We aim to investigate the correlation of CCNB1 polymorphisms to the efficiency of platinum-based chemotherapy in Chinese advanced NSCLC patients. We enrolled 972 patients with advanced NSCLC, and extracted DNA from their peripheral blood for genotyping CCNB1 four tagSNPs which selected from the Hapmap database. We analyzed the association of CCNB1 four tagSNPs with efficiency of platinum-based chemotherapy. We found that rs2069429 and rs2069433 of CCNB1 were associated with the OS of advanced NSCLC patients. Patients with GG genotype of rs2069429 had longer OS than non-GG patients (HR=0.81, 95%CI=0.68-0.95, p=0.009); and patients with AA genotype of rs2069433 had longer OS than non-AA patients (HR=0.78, 95%CI=0.61-0.98, p=0.036). And the haplotype GAAA of CCNB1 was a putative factor in subgroup patients with clinical stage IV. The association of CCNB1 polymorphisms and toxicities after platinum-based chemotherapy was assessed. Rs2069433 and rs350104 were related with gastrointestinal toxicity of platinum-based chemotherapy. The patients with GG genotype of rs2069433 (p=0.013) and/or non-GG genotype of rs350104 (p=0.042) may have a severe gastrointestinal toxicity after chemotherapy, and then clinician may can reduce the dosage of chemotherapy agents to avoid sever toxicities in these patients. In summary, CCNB1 polymorphisms may contribute to the clinical efficiency of platinum-based chemotherapy in advanced NSCLC patients, and it is helpful for the personalized treatment.

Using Serological Proteome Analysis to Identify Serum Anti-Nucleophosmin 1 Autoantibody as a Potential Biomarker in European-American and African-American Patients With Prostate Cancer

BACKGROUND

The prostate-specific antigen (PSA) testing has been widely implemented for the early detection and management of prostate cancer (PCa). However, the lack of specificity has led to overdiagnosis, resulting in many possibly unnecessary biopsies and overtreatment. Therefore, novel serological biomarkers with high sensitivity and specificity are of vital importance needed to complement PSA testing in the early diagnosis and effective management of PCa. This is particularly critical in the context of PCa health disparities, where early detection and management could help reduce the disproportionately high PCa mortality observed in African-American men. Previous studies have demonstrated that sera from patients with PCa contain autoantibodies that react with tumor-associated antigens (TAAs).

METHODS

The serological proteome analysis (SERPA) approach was used to identify tumor-associated antigens (TAAs) of PCa. In evaluation study, the level of anti-NPM1 antibody was examined in sera from test cohort, validation cohort, as well as European-American (EA) and African-American (AA) men with PCa by using immunoassay.

RESULTS

Nucleophosmin 1 (NPM1) as a 33 kDa TAA in PCa was identified and characterized by SERPA approach. Anti-NPM1 antibody level in PCa was higher than in benign prostatic hyperplasia (BPH) patients and healthy individuals. Receiver operating characteristic (ROC) curve analysis showed similar high diagnostic value for PCa in the test cohort (area under the curve (AUC):0.860) and validation cohort (AUC: 0.822) to differentiate from normal individuals and BPH. Interestingly, AUC values were significantly higher for AA PCa patients. When considering concurrent serum measurements of anti-NPM1 antibody and PSA, 97.1% PCa patients at early stage were identified correctly, while 69.2% BPH patients who had elevated PSA levels were found to be anti-NPM1 negative. Additionally, anti-NPM1 antibody levels in PCa patients at early stage significantly increased after surgery treatment.

CONCLUSION

This intriguing data suggested that NPM1 can elicit autoantibody response in PCa and might be a potential biomarker for the immunodiagnosis and prognosis of PCa, and for supplementing PSA testing in distinguishing PCa from BPH. Prostate 76:1375-1386, 2016. © 2016 Wiley Periodicals, Inc.

Immunoseroproteomic Profiling in African American Men with Prostate Cancer: Evidence for an Autoantibody Response to Glycolysis and Plasminogen-Associated Proteins

African American (AA) men suffer from a disproportionately high incidence and mortality of prostate cancer (PCa) compared with other racial/ethnic groups. Despite these disparities, African American men are underrepresented in clinical trials and in studies on PCa biology and biomarker discovery. We used immunoseroproteomics to profile antitumor autoantibody responses in AA and European American (EA) men with PCa, and explored differences in these responses. This minimally invasive approach detects autoantibodies to tumor-associated antigens that could serve as clinical biomarkers and immunotherapeutic agents. Sera from AA and EA men with PCa were probed by immunoblotting against PC3 cell proteins, with AA sera showing stronger immunoreactivity. Mass spectrometry analysis of immunoreactive protein spots revealed that several AA sera contained autoantibodies to a number of proteins associated with both the glycolysis and plasminogen pathways, particularly to alpha-enolase (ENO1). The proteomic data is deposited in ProteomeXchange with identifier PXD003968. Analysis of sera from 340 racially diverse men by enzyme-linked immunosorbent assays (ELISA) showed higher frequency of anti-ENO1 autoantibodies in PCa sera compared with control sera. We observed differences between AA-PCa and EA-PCa patients in their immunoreactivity against ENO1. Although EA-PCa sera reacted with higher frequency against purified ENO1 in ELISA and recognized by immunoblotting the endogenous cellular ENO1 across a panel of prostate cell lines, AA-PCa sera reacted weakly against this protein by ELISA but recognized it by immunoblotting preferentially in metastatic cell lines. These race-related differences in immunoreactivity to ENO1 could not be accounted by differential autoantibody recognition of phosphoepitopes within this antigen. Proteomic analysis revealed differences in the posttranslational modification profiles of ENO1 variants differentially recognized by AA-PCa and EA-PCa sera. These intriguing results suggest the possibility of race-related differences in the antitumor autoantibody response in PCa, and have implications for defining novel biological determinants of PCa health disparities.

MAD2B contributes to podocyte injury of diabetic nephropathy via inducing cyclin B1 and Skp2 accumulation

It is well documented that mitotic arrest deficiency (MAD)2B can inhibit the anaphase-promoting complex/cyclosome (APC/C) via cadherin (Cdh)1 and, consequently, can destroy the effective mitotic spindle checkpoint control. Podocytes have been observed to rapidly detach and die when being forced to bypass cell cycle checkpoints. However, the role of MAD2B, a cell cycle regulator, in podocyte impairment of diabetic nephropathy (DN) is unclear. In the present study, we investigated the significance of MAD2B in the pathogenesis of DN in patients, an animal model, and in vitro podocyte cultures. By Western blot and immunohistochemistry analyses, we found that MAD2B was evidently upregulated under high glucose milieu in vivo and in vitro, whereas Cdh1 was inhibited with high glucose exposure. Overexpression of MAD2B in podocytes by plasmid DNA transfection suppressed expression of Cdh1 and triggered the accumulation of cyclin B1 and S phase kinase-associated protein (Skp)2, two key molecules involving in cell cycle regulation, and the subsequent podocyte insult. In contrast, MAD2B deletion alleviated the high glucose-induced reduction of Cdh1 as well as the elevation of cyclin B1 and Skp2, which rescued the podocyte from damage. Taken together, our data demonstrate that MAD2B may play an important role in high glucose-mediated podocyte injury of DN via modulation of Cdh1, cyclin B1, and Skp2 expression.

Endogenous antibody responsiveness to epidermal growth factor receptor is associated with immunoglobulin allotypes and overall survival of patients with glioblastoma

BACKGROUND

Immunoglobulin γ marker (GM) and κ marker (KM) allotypes, hereditary antigenic determinants of γ and κ chains, respectively, have been shown to be associated with immunity to a variety of self and nonself antigens, but their possible contribution to immunity to the tumor-associated antigens epidermal growth factor receptor (EGFR) and EGFR variant (v)III has not been evaluated. The aim of the present investigation was to determine whether the interindividual variation in endogenous antibody responsiveness to EGFR and EGFRvIII is associated with particular GM, KM, and Fcγ receptor (FcγR) genotypes and whether antibody levels were associated with the overall survival of patients with glioblastoma.

METHODS

A total of 126 Caucasian participants with glioblastoma were genotyped for several GM, KM, and FcγR alleles and characterized for IgG antibodies to EGFR and EGFRvIII antigens.

RESULTS

The anti-EGFR antibody levels associated with GM 3/3 homozygotes and GM 3/17 heterozygotes were similar (15.9 vs 16.4 arbitrary units [AU]/µL) and significantly lower than those associated with GM 17/17 homozygotes (19.6 AU/µL; nominal P = .007). Participants homozygous for the GM 21 allele also had significantly higher levels of anti-EGFR antibodies than GM 5/5 homozygotes and GM 5/21 heterozygotes (20.1 vs 16.0 and 16.3 AU/µL; nominal P = .005). Similar associations were found with immune responsiveness to EGFRvIII. Higher anti-EGFR and anti-EGFRvIII antibody levels were associated with enhanced overall survival (16 vs 11 mo, nominal P = .038 and 20 vs 11 mo, nominal P = .004, respectively).

CONCLUSIONS

GM allotypes contribute to humoral immunity to EGFR in glioblastoma.

Preferential autoimmune response in prostate cancer to cyclin B1 in a panel of tumor-associated antigens

Previous studies have demonstrated that sera from patients with prostate cancer (PCa) contain autoantibodies that react with tumor-associated antigens (TAAs). Autoantibodies to cyclin B1 and fourteen other TAAs were detected by enzyme-linked immunosorbent assay (ELISA) and Western blotting in 464 sera from patients with PCa, benign prostatic hyperplasia (BPH), and other controls. Autoantibodies to cyclin B1 were detected in 31.0% of sera from randomly selected patients with PCa versus 4.8% in sera with BPH. In the further analysis, 31.4% of sera from PCa patients at the early stage contained anti-cyclin B1 autoantibody, and even 29.4% of patients who had normal prostate-specific antigen (PSA) levels in their serum samples were observed anti-cyclin B1 positive. The cumulative positive rate of autoantibodies against seven selected TAAs (cyclin B1, survivin, p53, DFS70/LEDGFp75, RalA, MDM2, and NPM1) in PCa reached 80.5%, significantly higher than that in normal control sera. In summary, autoantibody to cyclin B1 might be a potential biomarker for the immunodiagnosis of early stage PCa, especially useful in patients with normal PSA level. This study further supports the hypothesis that a customized TAA array can be used for enhancing anti-TAA autoantibody detection, and it may constitute a promising and powerful tool for immunodiagnosis of PCa.

Antigen cross-presentation of immune complexes

The ability of dendritic cells (DCs) to cross-present tumor antigens has long been a focus of interest to physicians, as well as basic scientists, that aim to establish efficient cell-based cancer immune therapy. A prerequisite for exploiting this pathway for therapeutic purposes is a better understanding of the mechanisms that underlie the induction of tumor-specific cytotoxic T-lymphocyte (CTL) responses when initiated by DCs via cross-presentation. The ability of humans DC to perform cross-presentation is of utmost interest, as this cell type is a main target for cell-based immunotherapy in humans. The outcome of a cross-presentation event is guided by the nature of the antigen, the form of antigen uptake, and the subpopulation of DCs that performs presentation. Generally, CD8α⁺ DCs are considered to be the most potent cross-presenting DCs. This paradigm, however, only applies to soluble antigens. During adaptive immune responses, immune complexes form when antibodies interact with their specific epitopes on soluble antigens. Immunoglobulin G (IgG) immune complexes target Fc-gamma receptors on DCs to shuttle exogenous antigens efficiently into the cross-presentation pathway. This receptor-mediated cross-presentation pathway is a well-described route for the induction of strong CD8⁺ T cell responses. IgG-mediated cross-presentation is intriguing because it permits the CD8⁻ DCs, which are commonly considered to be weak cross-presenters, to efficiently cross-present. Engaging multiple DC subtypes for cross-presentation might be a superior strategy to boost CTL responses in vivo. We here summarize our current understanding of how DCs use IgG-complexed antigens for the efficient induction of CTL responses. Because of its importance for human cell therapy, we also review the recent advances in the characterization of cross-presentation properties of human DC subsets.

Suggestive evidence that Fc variants of IgG2 and FcγRIIa loci interact to contribute to the risk of prostate cancer

GM and KM allotypes-hereditary antigenic variants of immunoglobulin γ and κ chains, respectively-and the genetic variants of activating Fcγ receptors (FcγR) are associated with the immunobiology of several malignant diseases, but their role in susceptibility to prostate cancer has not been examined. This investigation aimed to determine whether these genes-individually or in particular epistatic combinations-contribute to the risk of prostate cancer. We genotyped DNA from 200 Caucasian patients with prostate cancer and 185 healthy controls (matched for age, race, gender, and geography) for several GM, KM, FcγRIIa, and FcγRIIIa alleles by molecular methods. None of the genotypes by itself was associated with the risk of prostate cancer. However, particular alleles at GM 23 and FcγRIIa loci interactively contributed to the risk of this malignancy (p = 0.031), the odds ratios ranging from 0.44 in subjects homozygous for the GM 23- allele at the IgG2 locus and for the histidine allele at the FcγRIIa locus to 2.86 in subjects homozygous for the GM 23+ allele at the IgG2 locus and the histidine allele at the FcγRIIa locus. To our knowledge, this is the first report implicating GM and FcγR loci as risk/protective factors for prostate cancer. Additional, independent, studies are warranted to confirm and extend these findings.