Emanuela Romano

Baseline Peripheral Blood Biomarkers Associated with Clinical Outcome of Advanced Melanoma Patients Treated with Ipilimumab.

Purpose: To identify baseline peripheral blood biomarkers associated with clinical outcome following ipilimumab treatment in advanced melanoma patients. Experimental Design: Frequencies of myeloid-derived suppressor cells (MDSC) and regulatory T cells (Treg), serum lactate dehydrogenase (LDH), routine blood counts, and clinical characteristics were assessed in 209 patients. Endpoints were overall survival (OS) and best overall response. Statistical calculations were done by Kaplan–Meier and Cox regression analysis, including calibration and discrimination by C-statistics. Results: Low baseline LDH, absolute monocyte counts (AMC), Lin−CD14+HLA-DR−/low-MDSC frequencies, and high absolute eosinophil counts (AEC), relative lymphocyte counts (RLC), and CD4+CD25+FoxP3+-Treg frequencies were significantly associated with better survival, and were considered in a combination model. Patients (43.5%) presenting with the best biomarker signature had a 30% response rate and median survival of 16 months. In contrast, patients with the worst biomarkers (27.5%) had only a 3% response rate and median survival of 4 months. The occurrence of adverse events correlated with neither baseline biomarker signatures nor the clinical benefit of ipilimumab. In another model, limited to the routine parameters LDH, AMC, AEC, and RLC, the number of favorable factors (4 vs. 3 vs. 2–0) was also associated with OS (P < 0.001 for all pairwise comparisons) in the main study and additionally in an independent validation cohort. Conclusions: A baseline signature of low LDH, AMC, and MDSCs as well as high AEC, Tregs, and RLC is associated with favorable outcome following ipilimumab. Prospective investigation of the predictive impact of these markers following ipilimumab and other treatments, e.g., PD-1 antibodies, is warranted. Clin Cancer Res; 22(12); 2908–18. ©2016 AACR.

Baseline Biomarkers for Outcome of Melanoma Patients Treated with Pembrolizumab

Purpose: Biomarkers for outcome after immune-checkpoint blockade are strongly needed as these may influence individual treatment selection or sequence. We aimed to identify baseline factors associated with overall survival (OS) after pembrolizumab treatment in melanoma patients. Experimental Design: Serum lactate dehydrogenase (LDH), routine blood count parameters, and clinical characteristics were investigated in 616 patients. Endpoints were OS and best overall response following pembrolizumab treatment. Kaplan–Meier analysis and Cox regression were applied for survival analysis. Results: Relative eosinophil count (REC) ≥1.5%, relative lymphocyte count (RLC) ≥17.5%, ≤2.5-fold elevation of LDH, and the absence of metastasis other than soft-tissue/lung were associated with favorable OS in the discovery (n = 177) and the confirmation (n = 182) cohort and had independent positive impact (all P < 0.001). Their independent role was subsequently confirmed in the validation cohort (n = 257; all P < 0.01). The number of favorable factors was strongly associated with prognosis. One-year OS probabilities of 83.9% versus 14.7% and response rates of 58.3% versus 3.3% were observed in patients with four of four compared to those with none of four favorable baseline factors present, respectively. Conclusions: High REC and RLC, low LDH, and absence of metastasis other than soft-tissue/lung are independent baseline characteristics associated with favorable OS of patients with melanoma treated with pembrolizumab. Presence of four favorable factors in combination identifies a subgroup with excellent prognosis. In contrast, patients with no favorable factors present have a poor prognosis, despite pembrolizumab, and additional treatment advances are still needed. A potential predictive impact needs to be further investigated. Clin Cancer Res; 22(22); 5487–96. ©2016 AACR.

Proportions of blood-borne Vδ1+ and Vδ2+ T-cells are associated with overall survival of melanoma patients treated with ipilimumab

Human γδ T-cells possess regulatory and cytotoxic capabilities, and could potentially influence the efficacy of immunotherapies. We analysed the frequencies of peripheral γδ T-cells, including their most prominent subsets (Vδ1+ and Vδ2+ cells) and differentiation states in 109 melanoma patients and 109 healthy controls. We additionally analysed the impact of γδ T-cells on overall survival (OS) calculated from the first dose of ipilimumab in melanoma patients. Higher median frequencies of Vδ1+ cells and lower median frequencies of Vδ2+ cells were identified in patients compared to healthy subjects (Vδ1+: 30% versus 15%, Vδ2+: 39% versus 64%, both pxa0<xa00.001). Patients with higher frequencies of Vδ1+ cells (≥30%) had poorer OS (pxa0=xa00.043) and a Vδ1+ differentiation signature dominated by late-differentiated phenotypes. In contrast, higher frequencies of Vδ2+ cells (≥39%) were associated with longer survival (pxa0=xa00.031) independent of the M category or lactate dehydrogenasexa0level. Patients with decreasing frequencies of Vδ2+ cells under ipilimumab treatment had worse OS and a lower rate of clinical benefit than patients without such decreases. Therefore, we suggest frequencies of both Vδ1+ and Vδ2+ cells as candidate biomarkers for outcome in melanoma patients following ipilimumab. Further studies are needed to validate these results and to clarify whether they represent prognostic associations or whether γδ T-cells are specifically and/or functionally linked to the mode of action of ipilimumab.

Wnt/β-catenin signaling in melanoma: Preclinical rationale and novel therapeutic insights

WNT signaling regulates embryonic development and tissue homeostasis in the adult stage. Evolutionarily, activation of the WNT pathway is triggered by a large family of cytokines and activates a broad spectrum of downstream targets through two independent branches mediated by β-catenin (defined as canonical pathway) or PLC and small GTPase (defined as non-canonical pathway), respectively. Recent studies revealed the crucial role of WNT in the maintenance of cell metabolism and stemness as well as its deregulation in tumourigenesis and malignant transformation through oncogenic reprogramming, which contributes to cancer cell proliferation and differentiation, survival, stress response and resistance. In addition, multiple functional mutations discovered in human tumours have been reported to cause malignancy, indicating this pathway as a novel therapeutic target in oncology. Notably, emerging data highlights its involvement in the crosstalk between immune and cancer cells. However, contradictory effects have been also observed in different pre-clinical models when strategic(???) inhibitors are tested. In this review, we address the multifaceted regulatory mechanisms of WNT signaling in cancer, with a particular focus on current melanoma therapy, which has witnessed dramatic improvement in the last five years.

Peripheral CD8 effector-memory type 1 T-cells correlate with outcome in ipilimumab-treated stage IV melanoma patients

The role of the assessment of peripheral T-cell phenotypes in predicting overall survival (OS) after ipilimumab treatment is unclear. Here, we analysed mononuclear cells in the blood before and at different time points during treatment with ipilimumab in 137 late-stage melanoma patients. The proportions of baseline naïve and memory T-cells were measured by flow cytometry and correlated with OS, with an emphasis on PD-1 expression. High frequencies (>13%) of CD8 effector-memory type 1 (EM1) T-cells at baseline correlated with longer OS (pxa0=xa00.029) and higher clinical response rates (pxa0=xa00.01). The frequency of these EM1 cells and the M category had independent impacts on OS (hazard ratioxa0=xa01.5, pxa0=xa00.033; and hazard ratioxa0=xa01.9, pxa0=xa00.007). In contrast, high baseline frequencies of late stage-differentiated effector memory CD8 cells (>23.8%) were negatively associated with OS (pxa0=xa00.034) but did not correlate with clinical response. Following treatment, a decrease of CD8 cells from baseline to the time of the second drug dose and at later time points was strongly and consistently correlated with a high clinical response rate. Our observations thus suggest an important predictive role of baseline CD8 EM1 cells and changes in CD8 cells for clinical response of ipilimumab. Further validation of these biomarker candidates is warranted.

Mechanisms of Resistance to Immune Checkpoint Antibodies

Immunotherapy using checkpoint inhibitors has changed the way we treat several aggressive cancers such as melanoma, non-small cell lung and head & neck cancers, among others, with durable responses achieved in the metastatic setting. However, unfortunately, the vast majority of patients do not respond to checkpoint inhibition therapy and a minority of patients, who do respond to treatment, develop secondary resistance and experience relapse by mechanisms still inadequately understood. Emerging evidence shows that alterations in multiple signaling pathways are involved in primary and/or secondary resistance to checkpoint inhibition. In this review we discuss how selected cancer-cell autonomous cues may influence the outcome of cancer immunotherapy, particularly immune checkpoint inhibition.

Baseline β-catenin, programmed death-ligand 1 expression and tumour-infiltrating lymphocytes predict response and poor prognosis in BRAF inhibitor-treated melanoma patients

BACKGROUNDnThe activation of oncogenic Wnt/β-catenin pathway in melanoma contributes to a lack of T-cell infiltration. Whether baseline β-catenin expression in the context of tumour-infiltrating lymphocytes (TILs) and programmed death ligand-1 (PD-L1) overexpression correlates with prognosis of metastatic melanoma patients (MMPs) treated with mitogen-activated protein kinase, MAPK inhibitorxa0(MAPKi) monotherapy, however, has not been fully clarified.nnnPATIENTS AND METHODSnSixty-four pre-treatment formalin-fixed and paraffin embedded melanoma samples from MMP treated with a BRAF inhibitor (nxa0=xa039) or BRAF and MEK inhibitors (nxa0=xa025) were assessed for presence of β-catenin, PD-L1, cluster of differentiation (CD)8, CD103xa0and forkhead box protein P3 (FOXP3) expression by immunohistochemistry, and results were correlated with clinical outcome. Quantitative assessment of mRNA transcripts associated with Wnt/β-catenin pathway and immune response was performed in 51 patients.nnnRESULTSnWe found an inverse correlation between tumoural β-catenin expression and the level of CD8, CD103 or forkhead box protein P3 (FOXP3) positivity in the tumour microenvironment (TME). By multivariate analysis, PD-L1 <5% (odds ratio, OR 0.12, 95% confidence interval, CI 0.03-0.53, pxa0=xa00.005) and the presence of CD8+ T cells (OR 18.27, 95%CI 2.54-131.52, pxa0=xa00.004) were significantly associated with a higher probability of response to MAPKi monotherapy. Responding patients showed a significantly increased expression of mRNA transcripts associated with adaptive immunity and antigen presentation. By multivariate analysis, progression-free survival (PFS) (hazards ratio (HR)xa0=xa00.25 95%CI 0.10-0.61, pxa0=xa00.002) and overall survival (OS) (HRxa0=xa00.24 95%CI 0.09-0.67, pxa0=xa00.006) were longer in patients with high density of CD8+ T cells and β-catenin <10% than those without CD8+ T cells infiltration and β-catenin ≥10%.nnnCONCLUSIONnOur findings provide evidence that in the context of MAPKi monotherapy, immune subsets in the (TME) and gene signature predict prognosis in MMPs.

HPV circulating tumor DNA to monitor the efficacy of anti-PD-1 therapy in metastatic squamous cell carcinoma of the anal canal: A case report

Squamous cell carcinoma of the anal canal (SCCA) is a rare HPV‐associated cancer with limited sensitivity to standard chemotherapy. In a phase 2 study, nivolumab, an anti PD‐1 immune checkpoint inhibitor, demonstrated significant efficacy as single‐agent therapy in metastatic SCCA patients. Nevertheless, imaging assessment by standard RECIST criteria of the efficacy of immune therapy can be difficult in some patients due to tumor immune cell infiltration, and biomarkers of treatment efficacy are needed. We have previously developed a quantitative droplet digital PCR (ddPCR) technique to detect HPV circulating tumor DNA (HPV ctDNA), with excellent sensitivity and specificity. Here, we report, for the first time, the kinetics of HPV ctDNA during therapy in a patient with metastatic SCCA, who obtained sustained partial response to single‐agent nivolumab. We observed an early and very significant decrease of HPV ctDNA during therapy from the baseline level of 3713 copies/ml plasma to 564 copies/ml plasma at 4 weeks, and 156 copies/ml at 6 weeks, followed by a plateau. This observation provides proof‐of‐concept that HPV ctDNA can be used as a noninvasive early dynamic biomarker to monitor the efficacy of new immunotherapy agents.

Les inhibiteurs du cycle cellulaire et cancer du sein hormonodépendant

Dysregulation of cellular cycle is a key component of carcinogenesis and its targeting represents an interesting approach. Recently, the development of selective inhibitors of the cycle targeting the cyclin-dependent kinases (CDK) 4xa0and 6xa0revived interest in this therapeutic class after the failure of pan-inhibitors. Palbociclib, ribociclib, and abemaciclib are the 3xa0drugs with the most advanced development. They demonstrated preclinical activity in luminal breast cancer models and are under clinical evaluation. The first available studies demonstrate the value of these compounds with an improved prognosis of metastatic patients in combination with endocrine therapy (palbociclib, ribociclib) or in monotherapy (abemaciclib). The results of ongoing studies will clarify the role of these agents in our new strategies and the individualisation of biomarkers will help to define patients who benefit most from this approach.

Challenges of Oncoimmunology for Ovarian and Breast Cancers

Over the past decade, the ability of cancer cells to evade immune destruction has become recognized as one of the hallmarks of cancer. This understanding has paved the way for the development of novel therapeutic agents that can enhance activation of antitumor immune responses or reverse immunosuppressive mechanisms through which tumors escape immune-mediated rejection. The treatment of ovarian and breast cancers remains a therapeutic challenge, as these malignancies are often diagnosed in advanced stages, and many patients relapse despite appropriate management. Clinical trials have shown efficacy for various immunotherapeutic strategies, especially the use of tumor stroma-targeting antibodies; enhancement of tumor antigen presentation, such as with vaccines and toll-like receptor agonists; and the targeting of immunosuppressive mechanisms, via checkpoint blockade. Emerging preclinical and clinical data provide a strong rationale for combinatorial approaches in these malignancies.