Stratégies vaccinales contre le mélanome

Le mélanome est une pathologie de plus en plus fréquente, sévère, pour laquelle les traitements antitumoraux standards sont peu efficaces. Étant donné la chimiorésistance et la radiorésistance intrinsèque de cette tumeur, d’une part, et d’autre part l’existence d’un rejet spontané, certes rare, de certains mélanomes, de grands espoirs se portent sur les techniques d’immunothérapie. Le développement récent de techniques de surveillance immunologique, l’« immunomonitorage », la caractérisation de nombreux antigènes tumoraux et la découverte de cytokines nécessaires à la culture ex vivo de cellules dendritiques ont ouvert de nouvelles voies thérapeutiques. Cet article fait le point sur les différentes stratégies de vaccination contre le mélanome.Melanoma incidence increases and conventional antitumor therapies are often ineffective, encouraging the design of novel therapies. Several lines of evidence support the notion of an immunological control of melanoma growth. Based on this information, active immunotherapy (vaccination) and adoptive immunotherapy trials (T cell therapy) were conducted in metastatic melanoma patients. The proof of principle of effective immunotherapy was brought up by pionnering trials using tumor infiltrated lymphocytes in lymphodepleted recipients or anti-CTLA4 Ab leading to tumor eradication but also autoimmune diseases. With the identification and characterization of tumor antigens recognized by cytotoxic T lymphocytes, the utilization of tumor rejection antigens along with adjuvants become available as tumor vaccines. The last five years have witnessed the emergence of dendritic cell based-vaccines that were efficient in priming and/or boosting T cell responses in normal volunteers and patients. This review highlights preclinical bases of cancer vaccines, their clinical development and discusses their limits. Correlations between immunomonitoring and tumor regressions await larger trials

Transcriptional and non-transcriptional roles of LXRs in cancer cells

Liver X Receptors (LXRs) have been proposed to have some anticancer properties. LXRs affect cancer cell proliferation and cell death through mechanisms that seems mostly to rely on its transcriptional activities. We recently identified a new non-genomic role of LXR? in colon cancer cells. Under LXR agonist treatment, LXR? induces an atypical cell death called pyroptosis in vitro and in vivo. Together with other reports, we raise the importance of targeting LXRs in cancer treatment

FOLFIRI-bevacizumab as a second-line treatment for advanced biliary tract cancer after gemcitabine-based chemotherapy

BackgroundAdvanced biliary tract cancer (BTC) has a poor prognosis. Gemcitabine with platinum chemotherapy was the standard first-line chemotherapeutic regimen until the recent addition of anti-PD-1/PD-L1 antibodies. After disease progression, the only second-line chemotherapy that has demonstrated a survival benefit versus supportive care is FOLFOX (folinic acid, fluorouracil, and oxaliplatin), with a modest benefit. This study aimed to assess the efficacy and safety of second-line FOLFIRI (folinic acid, fluorouracil, and irinotecan) combined with bevacizumab for advanced BTC.MethodsThis single-center retrospective study enrolled patients with metastatic BTC (intrahepatic cholangiocarcinoma [ICC], extrahepatic cholangiocarcinoma [ECC], or gallbladder carcinoma) that progressed after first-line gemcitabine-based chemotherapy. FOLFIRI-bevacizumab was administered intravenously every 2 weeks [folinic acid 200 mg/m², fluorouracil 400 mg/m² (bolus), fluorouracil 2400 mg/m² (46-h continuous intravenous infusion), irinotecan 180 mg/m², and bevacizumab 5 mg/kg] until unacceptable toxicity, patient refusal, or disease progression.ResultsOverall, 28 patients received the FOLFIRI-bevacizumab regimen after gemcitabine-based chemotherapy. The median overall survival (OS) was 9.0 months (95% CI 6.4–16.5). The OS rate was 39.3% (95% CI 24.8–62.3) and 10.7% (95% CI 3.7–32.1) at 12- and 24-months respectively. The median progression-free survival (PFS) was 5.2 months (95% CI 3.1–10.2) with FOLFIRI-bevacizumab. The PFS rates at 12 months and 24 months were 17.9% (95% CI 8.19–39.5] and 10.7% (95% CI 3.7–31.2), respectively. The overall response rate (ORR) to FOLFIRI-bevacizumab was 23.1%, with a disease control rate (DCR) of 69.3%. Grade 3-4 adverse events (sAE) were reported in 20 patients (71.4%) treated with FOLFIRI-bevacizumab.ConclusionFOLFIRI-bevacizumab as a second-line treatment for advanced BTC after gemcitabine-based chemotherapy showed efficacy and safety with a promising tumor response rate in this retrospective single-center study

Comparison of hyperthermia and adrenaline to enhance the intratumoral accumulation of cisplatin in a murin model of peritoneal carcinomatosis

<p>Abstract</p> <p>Background</p> <p>The best method to deliver intraperitoneal chemotherapy (IPC) for peritoneal carcinomatosis from ovarian cancer is not well defined. The aim of this study was to assess the ability of hyperthermia and adrenaline to enhance the intratumoral accumulation of cisplatin in a rat model of peritoneal carcinomatosis.</p> <p>Methods</p> <p>Four groups of 5 BDIX rats with ovarian peritoneal carcinomatosis underwent IPC with 30 mg/l of cisplatin according to the following conditions: normothermia at 37° for 1 or 2 hours, hyperthermia at 42°C for 1 hour or normothermia at 37°C for 2 hours with 2 mg/l adrenaline. Tissue platinum content was measured by atomic absorption spectroscopy. The effect of hyperthermia, adrenaline and the duration of exposure to the drug was measured <it>in vivo </it>(tissue concentration of platinum in tumor, abdominal and extra abdominal tissues) and <it>in vitro </it>(cytotoxicity on human ovarian cancer cells).</p> <p>Results</p> <p><it>In vitro</it>, hyperthermia and longer exposure enhanced the accumulation and the cytotoxic effect of cisplatin on cancer cells. <it>In vivo</it>, only the 2 hours treatment with adrenaline resulted in increased platinum concentrations. The rats treated with adrenaline showed significantly lower concentrations of cisplatin in extra peritoneal tissues than those treated with hyperthermia.</p> <p>Conclusion</p> <p>Adrenaline is more effective than hyperthermia in order to enhance the intratumoral concentration of cisplatin in rats with peritoneal carcinomatosis from ovarian origin. It may also decrease the systemic absorption of the drug.</p

Production of Adenosine by Ectonucleotidases: A Key Factor in Tumor Immunoescape

It is now well known that tumor immunosurveillance contributes to the control of cancer growth. Many mechanisms can be used by cancer cells to avoid the antitumor immune response. One such mechanism relies on the capacity of cancer cells or more generally of the tumor microenvironment to generate adenosine, a major molecule involved in antitumor T cell response suppression. Adenosine is generated by the dephosphorylation of extracellular ATP released by dying tumor cells. The conversion of ATP into adenosine is mediated by ectonucleotidase molecules, namely, CD73 and CD39. These molecules are frequently expressed in the tumor bed by a wide range of cells including tumor cells, regulatory T cells, Th17 cells, myeloid cells, and stromal cells. Recent evidence suggests that targeting adenosine by inhibiting ectonucleotidases may restore the resident antitumor immune response or enhance the efficacy of antitumor therapies. This paper will underline the impact of adenosine and ectonucleotidases on the antitumor response

Tumor cells convert immature myeloid dendritic cells into TGF-β–secreting cells inducing CD4+CD25+ regulatory T cell proliferation

The mechanisms through which regulatory T cells accumulate in lymphoid organs of tumor-bearing hosts remain elusive. Our experiments indicate that the accumulation of CD4+CD25+ regulatory T cells (T reg cells) expressing FoxP3 and exhibiting immunosuppressive function originates from the proliferation of naturally occurring CD25+ T cells and requires signaling through transforming growth factor (TGF)–β receptor II. During tumor progression, a subset of dendritic cells (DCs) exhibiting a myeloid immature phenotype is recruited to draining lymph nodes. This DC subset selectively promotes the proliferation of T reg cells in a TGF-β–dependent manner in mice and rats. Tumor cells are necessary and sufficient to convert DCs into regulatory cells that secrete bioactive TGF-β and stimulate T reg cell proliferation. In conclusion, tumor expansion can stimulate T reg cells via a specific DC subset

465 Bintrafusp alfa in combination with chemotherapy in patients with stage IV NSCLC: safety and pharmacokinetic results of the INTR@PID LUNG 024 study

BackgroundBintrafusp alfa is a first-in-class bifunctional fusion protein composed of the extracellular domain of the TGF-βRII receptor (a TGF-β "trap") fused to a human IgG1 mAb blocking PD-L1. Here we report cumulative safety and pharmacokinetic (PK) results from the global, phase 1b/2 INTR@PID LUNG 024 study (NCT03840915), which evaluated bintrafusp alfa in combination with chemotherapy (CT) in patients with stage IV NSCLC.MethodsAdult patients with stage IV nonsquamous or squamous NSCLC and an ECOG PS ≤1 were included. Cohorts A, B, and C included patients with no prior systemic therapy; patients in cohort D had disease that progressed with previous anti–PD-(L)1 therapy. Cohorts received bintrafusp alfa 2400 mg every 3 weeks intravenously in combination with CT for 4 cycles (A [nonsquamous only]: cisplatin or carboplatin + pemetrexed; B: carboplatin + nab-paclitaxel or paclitaxel; C: cisplatin or carboplatin + gemcitabine; D: docetaxel) followed by bintrafusp alfa maintenance (monotherapy or in combination with pemetrexed in cohort A) for up to 31 cycles. The primary objective of this study was to evaluate the safety of bintrafusp alfa in combination with CT. Dose-limiting toxicities (DLTs) were assessed during a 3-week observation period. Serial samples were drawn to assess serum concentration and calculate PK parameters by noncompartmental analysis.ResultsAs of the May 5, 2021, data cutoff, 70 patients received bintrafusp alfa in combination with CT. Of 35 patients included in the DLT analysis, 4 experienced 1 DLT according to a safety monitoring committee (data cutoff May 5, 2021; A: n=1/8; B: n=1/8; C: n=0/8; D: n=2/11). Cumulative safety data are reported in table 1. PK data were available for 67 patients (A: n=38; B: n=9; C: n=8; D: n=12). PK profiles were similar across cohorts and between patients who did and did not experience a DLT. Observed bintrafusp alfa first-cycle exposures (Cmax, AUC, and Ctrough) were consistent with the published population PK (popPK) model.1Abstract 465 Table 1Safety results from the INTR@PID LUNG 024 studyConclusionsThe safety profile of bintrafusp alfa in combination with CT was manageable and similar to that reported for ICIs in combination with CT, with the exception of TGF-β–related skin lesions known to occur with TGF-β inhibition. No new safety signals were identified and there were no treatment-related deaths. The PK profile was consistent with the predicted monotherapy popPK model, suggesting no victim DDI potential for bintrafusp alfa with CT.AcknowledgementsThe authors thank the patients and their families, investigators, co-investigators, and the study teams at each of the participating centers, at the healthcare business of Merck KGaA, Darmstadt, Germany, and at EMD Serono, Billerica, Massachusetts, USA.Trial RegistrationNCT03840915ReferenceWilkins JJ, Vugmeyster Y, Dussault I. Population pharmacokinetic analysis of bintrafusp alfa in different cancer types. Adv Ther 2019;36:2414–2433.Ethics ApprovalThe trial was approved by each site's independent ethics committee

CD4+CD25+ regulatory T cells inhibit natural killer cell functions in a transforming growth factor–β–dependent manner

Tumor growth promotes the expansion of CD4+CD25+ regulatory T (T reg) cells that counteract T cell–mediated immune responses. An inverse correlation between natural killer (NK) cell activation and T reg cell expansion in tumor-bearing patients, shown here, prompted us to address the role of T reg cells in controlling innate antitumor immunity. Our experiments indicate that human T reg cells expressed membrane-bound transforming growth factor (TGF)–β, which directly inhibited NK cell effector functions and down-regulated NKG2D receptors on the NK cell surface. Adoptive transfer of wild-type T reg cells but not TGF-β−/− T reg cells into nude mice suppressed NK cell–mediated cytotoxicity, reduced NKG2D receptor expression, and accelerated the growth of tumors that are normally controlled by NK cells. Conversely, the depletion of mouse T reg cells exacerbated NK cell proliferation and cytotoxicity in vivo. Human NK cell–mediated tumor recognition could also be restored by depletion of T reg cells from tumor-infiltrating lymphocytes. These findings support a role for T reg cells in blunting the NK cell arm of the innate immune system

Radiomics combined with transcriptomics to predict response to immunotherapy from patients treated with PD-1/PD-L1 inhibitors for advanced NSCLC

IntroductionIn this study, we aim to build radiomics and multiomics models based on transcriptomics and radiomics to predict the response from patients treated with the PD-L1 inhibitor.Materials and methodsOne hundred and ninety-five patients treated with PD-1/PD-L1 inhibitors were included. For all patients, 342 radiomic features were extracted from pretreatment computed tomography scans. The training set was built with 110 patients treated at the Léon Bérard Cancer Center. An independent validation cohort was built with the 85 patients treated in Dijon. The two sets were dichotomized into two classes, patients with disease control and those considered non-responders, in order to predict the disease control at 3 months. Various models were trained with different feature selection methods, and different classifiers were evaluated to build the models. In a second exploratory step, we used transcriptomics to enrich the database and develop a multiomic signature of response to immunotherapy in a 54-patient subgroup. Finally, we considered the HOT/COLD status. We first trained a radiomic model to predict the HOT/COLD status and then prototyped a hybrid model integrating radiomics and the HOT/COLD status to predict the response to immunotherapy.ResultsRadiomic signature for 3 months’ progression-free survival (PFS) classification: The most predictive model had an area under the receiver operating characteristic curve (AUROC) of 0.94 on the training set and 0.65 on the external validation set. This model was obtained with the t-test selection method and with a support vector machine (SVM) classifier. Multiomic signature for PFS classification: The most predictive model had an AUROC of 0.95 on the training set and 0.99 on the validation set. Radiomic model to predict the HOT/COLD status: the most predictive model had an AUROC of 0.93 on the training set and 0.86 on the validation set. HOT/COLD radiomic hybrid model for PFS classification: the most predictive model had an AUROC of 0.93 on the training set and 0.90 on the validation set.ConclusionIn conclusion, radiomics could be used to predict the response to immunotherapy in non-small-cell lung cancer patients. The use of transcriptomics or the HOT/COLD status, together with radiomics, may improve the working of the prediction models