Molecular Classification of Grade 3 Endometrioid Endometrial Cancers Identifies Distinct Prognostic Subgroups.

Our aim was to investigate whether molecular classification can be used to refine prognosis in grade 3 endometrial endometrioid carcinomas (EECs). Grade 3 EECs were classified into 4 subgroups: p53 abnormal, based on mutant-like immunostaining (p53abn); MMR deficient, based on loss of mismatch repair protein expression (MMRd); presence of POLE exonuclease domain hotspot mutation (POLE); no specific molecular profile (NSMP), in which none of these aberrations were present. Overall survival (OS) and recurrence-free survival (RFS) rates were compared using the Kaplan-Meier method (Log-rank test) and univariable and multivariable Cox proportional hazard models. In total, 381 patients were included. The median age was 66 years (range, 33 to 96 y). Federation Internationale de Gynecologie et d'Obstetrique stages (2009) were as follows: IA, 171 (44.9%); IB, 120 (31.5%); II, 24 (6.3%); III, 50 (13.1%); IV, 11 (2.9%). There were 49 (12.9%) POLE, 79 (20.7%) p53abn, 115 (30.2%) NSMP, and 138 (36.2%) MMRd tumors. Median follow-up of patients was 6.1 years (range, 0.2 to 17.0 y). Compared to patients with NSMP, patients with POLE mutant grade 3 EEC (OS: hazard ratio [HR], 0.36 [95% confidence interval, 0.18-0.70]; P=0.003; RFS: HR, 0.17 [0.05-0.54]; P=0.003) had a significantly better prognosis; patients with p53abn tumors had a significantly worse RFS (HR, 1.73 [1.09-2.74]; P=0.021); patients with MMRd tumors showed a trend toward better RFS. Estimated 5-year OS rates were as follows: POLE 89%, MMRd 75%, NSMP 69%, p53abn 55% (Log rank P=0.001). Five-year RFS rates were as follows: POLE 96%, MMRd 77%, NSMP 64%, p53abn 47% (P=0.000001), respectively. In a multivariable Cox model that included age and Federation Internationale de Gynecologie et d'Obstetrique stage, POLE and MMRd status remained independent prognostic factors for better RFS; p53 status was an independent prognostic factor for worse RFS. Molecular classification of grade 3 EECs reveals that these tumors are a mixture of molecular subtypes of endometrial carcinoma, rather than a homogeneous group. The addition of molecular markers identifies prognostic subgroups, with potential therapeutic implications.

Traceability in stem cell research: from participant sample to induced pluripotent stem cell and back.

This paper describes a traceability system developed for the Stem cells for Biological Assays of Novel drugs and prediCtive toxiCology consortium. The system combines records and labels that to biological material across geographical locations and scientific processes from sample donation to induced pluripotent stem cell line. The labeling system uses a unique identification number to link every aliquot of sample at every stage of the reprogramming pathway back to the original donor. Only staff at the clinical recruitment site can reconnect the unique identification number to the identifying details of a specific donor. This ensures the system meets ethical and legal requirements for protecting privacy while allowing full traceability of biological material. The system can be adapted to other projects and for use with different primary sample types.

Robo4 vaccines induce antibodies that retard tumor growth.

Tumor endothelial specific expression of Robo4 in adults identifies this plasma membrane protein as an anti-cancer target for immunotherapeutic approaches, such as vaccination. In this report, we describe how vaccination against Robo4 inhibits angiogenesis and tumor growth. To break tolerance to the auto-antigen Robo4, mice were immunised with the extracellular domain of mouse Robo4, fused to the Fc domain of human immunoglobulin within an adjuvant. Vaccinated mice show a strong antibody response to Robo4, with no objectively detectable adverse effects on health. Robo4 vaccinated mice showed impaired fibrovascular invasion and angiogenesis in a rodent sponge implantation assay, as well as a reduced growth of implanted syngeneic Lewis lung carcinoma. The anti-tumor effect of Robo4 vaccination was present in CD8 deficient mice but absent in B cell or IgG1 knockout mice, suggesting antibody dependent cell mediated cytotoxicity as the anti-vascular/anti-tumor mechanism. Finally, we show that an adjuvant free soluble Robo4-carrier conjugate can retard tumor growth in carrier primed mice. These results point to appropriate Robo4 conjugates as potential anti-angiogenic vaccines for cancer patients.

Adenovirus E1A interacts directly with, and regulates the level of expression of, the immunoproteasome component MECL1.

Proteasomes represent the major non-lysosomal mechanism responsible for the degradation of proteins. Following interferon γ treatment 3 proteasome subunits are replaced producing immunoproteasomes. Adenovirus E1A interacts with components of the 20S and 26S proteasome and can affect presentation of peptides. In light of these observations we investigated the relationship of AdE1A to the immunoproteasome. AdE1A interacts with the immunoproteasome subunit, MECL1. In contrast, AdE1A binds poorly to the proteasome ß2 subunit which is replaced by MECL1 in the conversion of proteasomes to immunoproteasomes. Binding sites on E1A for MECL1 correspond to the N-terminal region and conserved region 3. Furthermore, AdE1A causes down-regulation of MECL1 expression, as well as LMP2 and LMP7, induced by interferon γ treatment during Ad infections or following transient transfection. Consistent with previous reports AdE1A reduced IFNγ-stimulated STAT1 phosphorylation which appeared to be responsible for its ability to reduce expression of immunoproteasome subunits.

A phase II study of adoptive immunotherapy using dendritic cells pulsed with tumor lysate in patients with hepatocellular carcinoma.

UNLABELLED: This is a phase II clinical trial investigating the safety and efficacy of intravenous vaccination with mature autologous dendritic cells (DCs) pulsed ex vivo with a liver tumor cell line lysate (HepG2) in patients with advanced hepatocellular carcinoma (HCC). HCC is an attractive target for immunotherapy as evidenced by an active recruitment of tumor-infiltrating lymphocytes that are capable of lysing autologous tumor cells in ex vivo studies. DCs are the most potent antigen-presenting cells, with the capacity to take up, process, and present tumor antigens to T cells and stimulate an immune response, thus providing a rational platform for vaccine development. Thirty-five patients with advanced HCC and not suitable for radical or loco-regional therapies received a maximum of six DC vaccinations each at 3-week intervals. In total, 134 DC infusions were administered with no significant toxicity and no evidence of autoimmunity. Twenty-five patients who received at least three vaccine infusions were assessed clinically for response. The radiologically determined disease control rate (combined partial response and stable disease >or=3 months) was 28%. In 17 patients the baseline serum alpha-fetoprotein (AFP) was >or= 1,000 ng/mL; in four of these patients, it fell to <30% of baseline following vaccination. In one patient there was a radiological partial response associated with a fall in AFP to <10% of baseline. Immune responses were assessed using an ELIspot assay of interferon-gamma (IFN-gamma) release. In several cases there was induction of T cell responses to the vaccine and/or AFP following vaccination. CONCLUSION: Autologous DC vaccination in patients with HCC is safe and well tolerated with evidence of antitumor efficacy assessed radiologically and serologically, with generation of antigen-specific immune responses in some cases.

Human papillomavirus (HPV) type 16-specific CD8+ T cell responses in women with high grade vulvar intraepithelial neoplasia.

Human papillomavirus (HPV)-associated vulvar intraepithelial neoplasia (VIN) has serious sequelae for the sufferer. Current treatments are associated with poor response and high relapse rates. The development of HPV-specific T cell immunotherapies offers a new approach to treatment. This will require a detailed understanding of the spectrum of T cell responses induced by HPV antigens, and how effectively viral antigens can be accessed by the immune system. We have investigated the frequency and spectrum of HPV16-specific CD8+ T cell responses to three HPV16 antigens in 9 women with high grade VIN (VIN3). CD4-depleted populations of responder cells were screened against overlapping 30-35mer peptides covering the sequences of HPV16 E6, E7 and E4 using ELISPOT assays of IFN-gamma release. We demonstrated CD8+ T cell reactivity to one or more of the proteins in 6 of 9 patient samples. All 6 of these responders recognised peptides covering the E7 protein, 3 of 9 women responded to E6 peptides, but no reactivity was seen to E4. Our results suggest that HPV16-specific cytotoxic T cells (CTLs) are relatively common in women with persistent VIN3. The HPV-specific CTL response, however, seems to be ineffective. There is some evidence that there are problems associated with the processing and presentation of HPV antigens by the infected vulvar epithelium. It will be crucial to address this in the design of any T cell based therapy for HPV-associated VIN and vulval cancer.

Detection of CD8+ T cell responses to human papillomavirus type 16 antigens in women using imiquimod as a treatment for high-grade vulval intraepithelial neoplasia.

OBJECTIVES: To investigate CD8+ T cell reactivity to human papillomavirus (HPV) 16 antigens in patients with high-grade vulval intraepithelial neoplasia (VIN) before, during and after treatment with 5% imiquimod cream. METHODS: CD8-enriched responder cell populations were obtained from 10 patients with high-grade VIN using imiquimod cream as a treatment. Overlapping synthetic peptides covering the entire primary sequences of the HPV16 E6, E7 and E4 proteins were used to screen for CD8+ T cell responses using an ELISPOT assay of interferon (IFN)-gamma release. RESULTS: Reactivity to the proteins was detected in all patients on at least one occasion. With the exception of one patient, CD8+ T cell reactivity generally increased at some stage during treatment. The magnitude and specificities of responses changed over the treatment period. This was particularly noticeable in response to peptides derived from the E4 protein. CD8+ T cell reactivity to HPV16 E7 appeared to be dominant amongst women with high-grade VIN. The magnitude and specificity of response had no correlation with clinical response to imiquimod. CONCLUSIONS: HPV16 specific CD8+ T cell activity was detected in patients with high-grade VIN. Imiquimod use appeared to increase the magnitude of the response and broaden the specificity of response in some patients. Despite the presence of these CD8+ T cells, the disease state persisted; therefore, a role for HPV-specific cytotoxic T cells (CTLs) in VIN resolution remains unproven.

Detection of CD4(+)- and CD8(+)-T-cell responses to human papillomavirus type 1 antigens expressed at various stages of the virus life cycle by using an enzyme-linked immunospot assay of gamma interferon release.

Human papillomavirus (HPV) antigens are expressed in epithelial cells at different stages of differentiation, and this may affect how they are handled by the immune system. We assessed the relative immunogenicities of four different HPV type 1 proteins: E6 and E7, which are made early in basal or parabasal cells; E4, which is made suprabasally in differentiating cells; and L1, a late protein which appears in the highly differentiated upper spinous layers. Pools of 15-mer peptides covering the primary sequences of all four proteins were used to screen 15 normal donors in enzyme-linked immunospot assays of gamma interferon release for both CD4(+)- and CD8(+)-T-cell reactivities. CD8(+)-T-cell responses were detected to the L1 protein in 7 of the 15 samples examined. No responses to E6, E7, or E4 were detected. CD4(+)-T-cell reactivities were again detected in 7 of the 15 donors. A broader spectrum of responses to E6 (three of seven), E4 (six of seven), and L1 (three of seven) was apparent, but there was no reactivity to E7. The predominant CD4(+) response was to E4. Reactivities were seen in some cases to corresponding regions on other common HPV types but were probably due to a multiple infection rather than to a cross-reaction. Antibodies to HPV1 virus-like particles were detected in 12 of the 15 (80%) donors, but antibody status did not correlate with T-cell reactivity. The differences in the relative immunogenicities of the four proteins revealed in this study are discussed in relation to how they may be processed and presented to the immune system by differentiating epithelial cells.