Feasibility of health-related quality of life (HRQoL) assessment for cancer patients using electronic patient-reported outcome (ePRO) in daily clinical practice

Quality of Life Research - Routine Electronic Monitoring of Health-Related Quality of Life (HRQoL) (REMOQOL) in clinical care with real-time feedback to physicians could help to enhance...     

Cytotoxic T lymphocytes: role in immunosurveillance and in immunotherapy

Experiments in mice and recent human clinical studies have clearly shown the contribution of CD8+ T lymphocyte in the control of tumor development. CD8+ T lymphocytes are a constitutive component of the immune response during the development of cancer. In murine models, the efficiency of various cancer vaccines mainly depends on their ability to induce CD8+ T lymphocytes. Clinical responses in immunotherapy treated cancer patients have been associated with the presence of antitumor specific CD8+ T lymphocytes. In spontaneous regressive melanomas, intratumor antigen specific CD8+ cytotoxic T cells were expanded suggesting their involvement in the tumor shrinkage. Administration of antitumor specific cytotoxic T clones in mice resulted in antitumor responses which directly demonstrated the therapeutic efficiency of these cells. However, in most cases during cancer progression, the presence of antitumor CD8 T lymphocyte is not associated with clinical responses. Intrinsic functional abnormalities of these cells or a defect of CD8+ T cell migration to the tumor may in part explain their failure to inhibit tumor development. On the other hand, tumors also develop immune escape mechanisms (down modulation of tumor antigens, secretion of immunosuppressive factors, expression of anti-apoptotic molecules by the tumors, or pro-apoptotic factors inducing T cell death) to resist to the CD8+ T cell attack. To circumvent these tumor escape mechanisms, efficient cancer vaccines will have to recruit CD8+ T cells associated with other immune effectors.     

Prognostic value of baseline seric Syndecan‐1 in initially unresectable metastatic colorectal cancer patients: a simple biological score

In first‐line metastatic colorectal cancer (mCRC), baseline prognostic factors allowing death risk and treatment strategy stratification are lacking. Syndecan‐1 (CD138) soluble form was never described as a prognostic biomarker in mCRC. We investigated its additional prognostic value for overall survival (OS). mCRC patients with unresectable disease at diagnosis were treated with bevacizumab‐based chemotherapy in two independent prospective clinical trials (development set: n = 126, validation set: n = 51, study NCT00489697 and study NCT00544011, respectively). Serums were collected at baseline for CD138 measurement. OS determinants were assessed and, based on the final multivariate model, a prognostic score was proposed. Two independent OS prognostic factors were identified: Lactate Dehydrogenase (LDH) high level (p = 0.0066) and log‐CD138 high level (p = 0.0190). The determination of CD138 binary information (cutoff: 75 ng/mL) allowed the assessment of a biological prognostic score with CD138 and LDH values, identifying three risk groups for death (median OS= 38.9, 30.1 and 19.8 months for the low, intermediate and high risk groups, respectively; p < 0.0001). This score had a good discrimination ability (C‐index = 0.63). These results were externally confirmed in the validation set. Our study provides robust evidence in favor of the additional baseline soluble CD138 prognostic value for OS, in mCRC patients. A simple biological scoring system is proposed including LDH and CD138 binary status values.     

A decrease of regulatory T cells correlates with overall survival after sunitinib-based antiangiogenic therapy in metastatic renal cancer patients

Sunitinib, an antiangiogenic molecule, is one of the first-line standard of care in the treatment of patients with metastatic renal cell carcinoma. However, it only benefits to a subgroup of patients and no predictive markers of sunitinib efficacy have been identified. Twenty-eight metastatic renal cell carcinomas were treated with sunitinib-based therapy and another subgroup of 7 primary renal cell cancer patients were also treated by sunitinib in a neoadjuvant trial. Measurements of CD3+CD4+CD25(hi) Foxp3+ regulatory T cells, an immunosuppressive cell population, were performed before and after each cycle of treatment in blood and tumor in a prospective study. We observed a decrease in the number of peripheral blood Foxp3+ regulatory T cells after each cycle of sunitinib-based therapy. The overall survival was significantly longer in patients showing a decrease in the number of Foxp3+ regulatory T cells after 2 or 3 cycles of treatment (P<0.05). The decrease in the number of regulatory T cells positively correlated with their number at baseline (P<0.01), but not with modification of tumor volume defined by Response Evaluation Criteria in Solid Tumors criteria. The clinical relevance of these results was also supported by an intratumoral decrease of regulatory T cells in 5 out of 7 patients treated by sunitinib in a neoadjuvant trial. Our study represents the first work reporting that the measurement of regulatory T cells may have a predictive value on antiangiogenic response. Antiangiogenic therapy also reversed immunosuppression in the tumor microenvironment which provides novel argument in human to favor its combination with immunotherapy.     

Analysis and characterization of antitumor T-cell response after administration of dendritic cells loaded with allogeneic tumor lysate to metastatic melanoma patients

The primary goal of cancer vaccines is to induce CD8+ T cells specific for tumor-associated antigens (TAA) but the characterization of these cells has been difficult because of the low sensitivity of ex vivo assays. Here, we focused on TAA-specific CD8+ T-cell responses in melanoma patients after vaccination with autologous dendritic cells loaded with lysates derived from allogeneic tumor-cell lines (Lysate-DC). Out of 40 patients treated, 16 patients developed immune response to tumor-cell lysate and/or CD8+ T cells specific for differentiation and cancer-testis antigens. TAA-specific CD8+ T-cell responses were detected by interferon (IFN)-gamma enzyme-linked immunospot after in vitro sensitization and were, either transient during the treatment period or delayed, that is, observed after completion of all vaccinations. We could not correlate these immune responses to clinical data as none of the patients achieved an overall objective response according to Response Evaluation Criteria in Solid Tumors criteria. Three patients were reported as stable disease and 10 patients presented evidence of antitumor activity. We found that TAA-specific T cells characterized in 4 patients produced perforin ex vivo, but no IFN-gamma in enzyme-linked immunospot. Differential expression of IFN-gamma and perforin was also observed for viral-specific T cells. Altogether, our results show that Lysate-DC therapy elicited tumor-specific CD8+ T cells nonlimited to human leukocyte antigen-A2+ patients, with some T cells secreting perforin ex vivo and IFN-gamma only after restimulation. The differential expression of perforin and IFN-gamma by antitumor and antiviral CD8+ T cells supports that the sole use of IFN-gamma production to monitor T cells overlooks functional T-cell subpopulations triggered by vaccines.     

A CCR4 antagonist combined with vaccines induces antigen-specific CD8+ T cells and tumor immunity against self antigens

Regulatory T cells (Tregs) may impede cancer vaccine efficacy in hematologic malignancies and cancer. CCR4 antagonists, an emergent class of Treg inhibitor, have been shown to block recruitment of Tregs mediated by CCL22 and CCL17. Our aim was to demonstrate the ability of a CCR4 antagonist (a small chemical molecule identified in silico) when combined with vaccines to break peripheral tolerance controlled by Tregs, a prerequisite for the induction of CD8(+) T cells against self Ags. Immunization of transgenic or normal mice expressing tumor-associated self Ags (Her2/neu, OVA, gp100) with a CCR4 antagonist combined with various vaccines led to the induction of effector CD8(+) T cells and partial inhibition of tumor growth expressing self Ags in both prophylactic and therapeutic settings. The CCR4 antagonist was more efficient than cyclophosphamide to elicit anti-self CD8(+) T cells. We also showed that the population of Tregs expressing CCR4 corresponded to memory (CD44(high)) and activated (ICOS(+)) Tregs, an important population to be targeted to modulate Treg activity. CCR4 antagonist represents a competitive class of Treg inhibitor able to induce functional anti-self CD8(+) T cells and tumor growth inhibition when combined with vaccines. High expression of CCR4 on human Tregs also supports the clinical development of this strategy.     

CD20 alternative splicing isoform generates immunogenic CD4 helper T epitopes

Cancer‐specific splice variants gain significant interest as they generate neo‐antigens that could be targeted by immune cells. CD20, a membrane antigen broadly expressed in mature B cells and in B cell lymphomas, is subject to an alternative splicing named D393‐CD20 leading to loss of membrane expression of the spliced isoform. D393‐CD20 expression is detectable in transformed B cells and upregulated in various lymphoma B cells. In this study, we show that D393‐CD20 is translated in malignant B cells and that D393‐CD20 specific CD4 T cells producing IFN‐γ are present in B‐cell lymphoma patients. Then, we have investigated whether the 20mer D393‐CD20 peptide spanning the splicing site might be targeted by the immune system and we have shown that D393‐CD20‐specific CD4 Th1 clones could directly recognize malignant B cell lines and kill autologous lymphoma B cells indicating that D393‐CD20‐derived epitopes are naturally processed and presented on tumor cells. Finally, D393‐CD20 peptide‐based vaccination induced specific CD8 and CD4 T cell responses in HLA‐humanized transgenic mice suggesting the presentation of D393‐CD20 derived peptides on both HLA Class‐I and ‐II. These findings support further investigations on the potential use of D393‐CD20 directed specific immunotherapy in B cell malignancies.     

The Shiga toxin B-subunit targets antigen in vivo to dendritic cells and elicits anti-tumor immunity

The non-toxic B-subunit of Shiga toxin (STxB) interacts with the glycolipid Gb3, which is preferentially expressed on dendritic cells (DC) and B cells. After administration of STxB chemically coupled to OVA (STxB-OVA) in mice, we showed that the immunodominant OVA(257-264) peptide restricted by K(b) molecules is specifically presented by CD11c+ CD8alpha- DC, some of them displaying a mature phenotype. Using mice carrying a transgene encoding a diphtheria toxin receptor (DTR) under the control of the murine CD11c promoter, which allows inducible ablation of DC, we showed that DC are required for efficient priming of CTL after STxB-OVA vaccination. Immunization of mice with STxB-OVA induced OVA-specific CD8+ T cells detected ex vivo; these cells were long lasting, since they could be detected even 91 days after the last immunization and were composed of both central and memory T cells. Vaccination of mice with STxB-OVA and STxB coupled to E7, a protein derived from HPV16, inhibited tumor growth in prophylactic and therapeutic experiments. This effect was mainly mediated by CD8+ T cells. STxB therefore appears to be a powerful carrier directly targeting DC in vivo, resulting in a strong and durable CTL response associated with tumor protection.