Stratégies thérapeutiques innovantes pour stimuler la réponse immune antitumorale de cytotoxiques utilisés pour le traitement des cancers du sein

Cette dernière décennie, de nombreuses données cliniques et pré-cliniques ont démontrées le rôle primordial du système immunitaire dans l'efficacité des chimiothérapies cytotoxiques. Ceci est lié, en partie, au déclenchement d'une mort cellulaire immunogène (MCI) par certains cytotoxiques, stimulant l'adjuvanticité des cellules tumorales. La MCI de la cellule tumorale est caractérisée par l'émission de signaux de dangers permettant de favoriser le recrutement et l'activation des cellules dendritiques, ainsi que la réponse immune antitumorale adaptative médiée par les lymphocytes T. La première étape de la MCI est l'exposition de la calréticuline à la face externe de la membrane plasmique, favorisant la phagocytose par les cellules dendritiques. Ensuite, les cellules tumorales sécrètent de l'ATP dans le milieu extra-cellulaire, par un mécanisme d'exocytose lysosomale dépendant de l'autophagie, favorisant le recrutement des cellules dendritiques. Enfin à un stade tardif, les cellules tumorales mourantes libèrent d'importantes quantité de protéines nucléaires dont l'HMGB1, ce qui entrainera la maturation des cellules dendritiques. Parmi les cancers du sein, le sous-type triple-négatif (TN) est le plus agressif, mais également le plus immunogène. Les patientes présentant un cancer du sein TN métastatique peuvent désormais bénéficier d'une combinaison de chimiothérapie et d'immunothérapie (avec un inhibiteur de checkpoint anti-PD-L1), même si les résultats présentés en septembre 2020 au congrès Européen de cancérologie (ESMO) remettent en cause l'efficacité de cette association. Malgré cette combinaison, la majorité des patientes rechuteront la première année. Le développement de thérapeutiques potentialisant la réponse immune est donc un enjeu majeur. La Dendrogénine A (DDA) est un métabolite suppresseur de tumeur caractérisé par l'équipe de Marc Poirot, avec une activité cytotoxique démontrée dans le cancer du sein hormono-dépendant, le mélanome et la leucémie aigüe myéloïde. La DDA induit une mort cellulaire par le déclenchement d'une autophagie dépendante de la voie du récepteur Liver-X-receptor (LXR) ß. Durant ma thèse, nous avons montré que la DDA exerçait une activité cytotoxique dans plusieurs lignées murines in vitro et in vivo, et une lignée humaine de cancer du sein TN in vitro. Nous avons montré que la DDA induisait des marqueurs d'autophagie dans ce modèle, in vitro et in vivo. Ensuite, nous avons montré qu'un traitement par DDA déclenchait les signaux de MCI sur deux lignées de cancer du sein TN (murine 4T1, et humaine MDA-MB-231), et une lignée murine de mélanome (B16F10). Les signaux de MCI induite par la DDA étaient supérieurs à ceux obtenus avec deux cytotoxiques standard, la doxorubicine et le mafosfamide. Nous avons enfin montré in vivo qu'une vaccination de souris immunocompétentes par des cellules mourantes traitées avec de la DDA, à partir de deux lignées cellulaires distinctes (4T1 et B16F10), induisait une protection prophylactique partielle lors du rechallenge de ces souris avec des cellules tumorales viables, en dehors de tout traitement systémique. Ces résultats nous montrent que la DDA pourrait être une nouvelle thérapeutique potentialisant la réponse immune antitumorale dans le cancer du sein TN.Last decade, several pre-clinical and clinical studies well demonstrated that the efficacy of conventional chemotherapies involves an immunological component. A part of the explanation comes from the demonstration that conventional chemotherapies can boost the adjuvanticity of cancer cells by inducing an immunogenic cell death (ICD). ICD of tumour cells drive an inflammatory response characterized by the activation of dendritic cells and the initiation of a cytotoxic T-lymphocyte immunity. During ICD, the reticulum endoplasmic stress promotes the translocation of the calreticulin protein to the cell surface, that facilitates the phagocytic uptake of tumour cells by immature dendritic cells. Then, the activation of autophagy in tumor cells induces the lysosomal secretion of ATP, that promotes the recruitment of dendritic cells. Lastly, dying cancer cells release a large amount of nuclear proteins including HMGB1, that drives the maturation of dendritic cells upon binding to TLR4. TNBC is defined as the most aggressive subtype of breast cancer, classified by its lack of expression of the hormonal receptor and the human epidermal growth factor receptor 2, but also considered as the most immunogenic subtype of breast cancer. A subset of TNBC patients are now eligible for immunotherapy in combination with chemotherapy, but all of them will finally relapse, mostly during the first year of treatment. Development of novel therapeutics to optimize immune response in these patients is urgently needed. Dendrogenin A has been characterized by the Marc Poirot's team as a tumour suppressor metabolite present in normal breast tissue, but absent in neoplastic breast tumour. DDA has an anti-tumour activity demonstrated in hormone-dependent breast cancer and melanoma cells, through the induction of an LXRß-dependent autophagy. During my thesis, we showed that DDA elicit cell death and autophagy in triple-negative breast cancer (TNBC) models in vitro and in vivo. Then, we demonstrated that DDA induced hallmarks of ICD in vitro in TNBC and melanoma cells lines. Indeed, we demonstrated that a treatment with DDA trigger (1) surface exposure of CALR, (2) release of ATP in the supernatant in an autophagy-dependent manner, and (3) release of HMGB1 in the supernatant. These danger signals were induced by DDA in a larger extent than doxorubicin and mafosfamide, described as two ICD-inducers. We then demonstrated in two different models that cancer cells undergoing ICD after being treated with DDA provide partial immune-mediated prophylactic protection against a subsequent challenge with living cancer cells of the same type. These results suggested that DDA could be a new therapeutic developed to potentiate antitumoral immune response in TNBC

Innovative therapeutics to enhance immune response in breast cancer

Cette dernière décennie, de nombreuses données cliniques et pré-cliniques ont démontrées le rôle primordial du système immunitaire dans l'efficacité des chimiothérapies cytotoxiques. Ceci est lié, en partie, au déclenchement d'une mort cellulaire immunogène (MCI) par certains cytotoxiques, stimulant l'adjuvanticité des cellules tumorales. La MCI de la cellule tumorale est caractérisée par l'émission de signaux de dangers permettant de favoriser le recrutement et l'activation des cellules dendritiques, ainsi que la réponse immune antitumorale adaptative médiée par les lymphocytes T. La première étape de la MCI est l'exposition de la calréticuline à la face externe de la membrane plasmique, favorisant la phagocytose par les cellules dendritiques. Ensuite, les cellules tumorales sécrètent de l'ATP dans le milieu extra-cellulaire, par un mécanisme d'exocytose lysosomale dépendant de l'autophagie, favorisant le recrutement des cellules dendritiques. Enfin à un stade tardif, les cellules tumorales mourantes libèrent d'importantes quantité de protéines nucléaires dont l'HMGB1, ce qui entrainera la maturation des cellules dendritiques. Parmi les cancers du sein, le sous-type triple-négatif (TN) est le plus agressif, mais également le plus immunogène. Les patientes présentant un cancer du sein TN métastatique peuvent désormais bénéficier d'une combinaison de chimiothérapie et d'immunothérapie (avec un inhibiteur de checkpoint anti-PD-L1), même si les résultats présentés en septembre 2020 au congrès Européen de cancérologie (ESMO) remettent en cause l'efficacité de cette association. Malgré cette combinaison, la majorité des patientes rechuteront la première année. Le développement de thérapeutiques potentialisant la réponse immune est donc un enjeu majeur. La Dendrogénine A (DDA) est un métabolite suppresseur de tumeur caractérisé par l'équipe de Marc Poirot, avec une activité cytotoxique démontrée dans le cancer du sein hormono-dépendant, le mélanome et la leucémie aigüe myéloïde. La DDA induit une mort cellulaire par le déclenchement d'une autophagie dépendante de la voie du récepteur Liver-X-receptor (LXR) ß. Durant ma thèse, nous avons montré que la DDA exerçait une activité cytotoxique dans plusieurs lignées murines in vitro et in vivo, et une lignée humaine de cancer du sein TN in vitro. Nous avons montré que la DDA induisait des marqueurs d'autophagie dans ce modèle, in vitro et in vivo. Ensuite, nous avons montré qu'un traitement par DDA déclenchait les signaux de MCI sur deux lignées de cancer du sein TN (murine 4T1, et humaine MDA-MB-231), et une lignée murine de mélanome (B16F10). Les signaux de MCI induite par la DDA étaient supérieurs à ceux obtenus avec deux cytotoxiques standard, la doxorubicine et le mafosfamide. Nous avons enfin montré in vivo qu'une vaccination de souris immunocompétentes par des cellules mourantes traitées avec de la DDA, à partir de deux lignées cellulaires distinctes (4T1 et B16F10), induisait une protection prophylactique partielle lors du rechallenge de ces souris avec des cellules tumorales viables, en dehors de tout traitement systémique. Ces résultats nous montrent que la DDA pourrait être une nouvelle thérapeutique potentialisant la réponse immune antitumorale dans le cancer du sein TN.Last decade, several pre-clinical and clinical studies well demonstrated that the efficacy of conventional chemotherapies involves an immunological component. A part of the explanation comes from the demonstration that conventional chemotherapies can boost the adjuvanticity of cancer cells by inducing an immunogenic cell death (ICD). ICD of tumour cells drive an inflammatory response characterized by the activation of dendritic cells and the initiation of a cytotoxic T-lymphocyte immunity. During ICD, the reticulum endoplasmic stress promotes the translocation of the calreticulin protein to the cell surface, that facilitates the phagocytic uptake of tumour cells by immature dendritic cells. Then, the activation of autophagy in tumor cells induces the lysosomal secretion of ATP, that promotes the recruitment of dendritic cells. Lastly, dying cancer cells release a large amount of nuclear proteins including HMGB1, that drives the maturation of dendritic cells upon binding to TLR4. TNBC is defined as the most aggressive subtype of breast cancer, classified by its lack of expression of the hormonal receptor and the human epidermal growth factor receptor 2, but also considered as the most immunogenic subtype of breast cancer. A subset of TNBC patients are now eligible for immunotherapy in combination with chemotherapy, but all of them will finally relapse, mostly during the first year of treatment. Development of novel therapeutics to optimize immune response in these patients is urgently needed. Dendrogenin A has been characterized by the Marc Poirot's team as a tumour suppressor metabolite present in normal breast tissue, but absent in neoplastic breast tumour. DDA has an anti-tumour activity demonstrated in hormone-dependent breast cancer and melanoma cells, through the induction of an LXRß-dependent autophagy. During my thesis, we showed that DDA elicit cell death and autophagy in triple-negative breast cancer (TNBC) models in vitro and in vivo. Then, we demonstrated that DDA induced hallmarks of ICD in vitro in TNBC and melanoma cells lines. Indeed, we demonstrated that a treatment with DDA trigger (1) surface exposure of CALR, (2) release of ATP in the supernatant in an autophagy-dependent manner, and (3) release of HMGB1 in the supernatant. These danger signals were induced by DDA in a larger extent than doxorubicin and mafosfamide, described as two ICD-inducers. We then demonstrated in two different models that cancer cells undergoing ICD after being treated with DDA provide partial immune-mediated prophylactic protection against a subsequent challenge with living cancer cells of the same type. These results suggested that DDA could be a new therapeutic developed to potentiate antitumoral immune response in TNBC

Molecular minimal residual disease in resected non-small cell lung cancer (NSCLC): results of specifically designed interventional clinical trials eagerly awaited

International audienceNo abstract availabl

STK11/LKB1 Modulation of the Immune Response in Lung Cancer: From Biology to Therapeutic Impact

International audienceThe STK11/LKB1 gene codes for liver kinase B1 (STK11/LKB1), a highly conserved serine/threonine kinase involved in many energy-related cellular processes. The canonical tumor-suppressive role for STK11/LKB1 involves the activation of AMPK-related kinases, a master regulator of cell survival during stress conditions. In pre-clinical models, inactivation of STK11/LKB1 leads to the progression of lung cancer with the acquisition of metastatic properties. Moreover, preclinical and clinical data have shown that inactivation of STK11/LKB1 is associated with an inert tumor immune microenvironment, with a reduced density of infiltrating cytotoxic CD8+ T lymphocytes, a lower expression of PD-(L)1, and a neutrophil-enriched tumor microenvironment. In this review, we first describe the biological function of STK11/LKB1 and the role of its inactivation in cancer cells. We report descriptive epidemiology, co-occurring genomic alterations, and prognostic impact for lung cancer patients. Finally, we discuss recent data based on pre-clinical models and lung cancer cohorts analyzing the results of STK11/LKB1 alterations on the immune system and response or resistance to immune checkpoint inhibitors

Homozygous Co-Deletion of Type I Interferons and CDKN2A Genes in Thoracic Cancers: Potential Consequences for Therapy

International audienceHomozygous deletion (HD) of the tumor suppressor gene CDKN2A is the most frequent genetic alteration in malignant pleural mesothelioma and is also frequent in non-small cell lung cancers. This HD is often accompanied by the HD of the type I interferons (IFN I) genes that are located closed to the CDKN2A gene on the p21.3 region of chromosome 9. IFN I genes encode sixteen cytokines (IFN-a, IFN-b…) that are implicated in cellular antiviral and antitumor defense and in the induction of the immune response. In this review, we discuss the potential influence of IFN I genes HD on thoracic cancers therapy and speak in favor of better taking these HD into account in patients monitoring

HRAS Q61L Mutation as a Possible Target for Non-Small Cell Lung Cancer: Case Series and Review of Literature

International audienceIntroduction: Assessment of actionable gene mutations and oncogene fusions have made a paradigm shift in treatment strategies of non-small cell lung cancer (NSCLC). HRAS mutations involved around 0.2-0.8% of NSCLC patients, mostly on codon 61. For these patients, few data are available regarding clinical characteristics and response to therapies.Methods: Next-Generation Sequencing (NGS) done routinely at Nantes University Hospital was used to identify HRAS molecular alterations in NSCLC patients. We identified and described four HRAS p.GlnQ61Leu mutated patients. Literature of previously HRAS-mutant NSCLC cases was reviewed, and available data in solid tumour with the most advanced H-Ras specific inhibitor, tipifarnib, were presented.Results: Of 1614 patients diagnosed with advanced NSCLC from January 2018 to December 2020, four (0.25%) had HRAS p.Gln61Leu mutation. Three of them died during the first-line systemic therapy. Furthermore, three additional cases were identified in literature. All cases were current or former smokers, most of them had pleural or pericardial effusion at diagnosis.Conclusions: The clinical course of patients with HRAS-mutant NSCLC remains unclear. Furthers cases should be identified in order to clarify prognosis and response to therapies. Tipifarnib, a farnesyl transferase inhibitor, is a promising candidate to target HRAS-mutant tumours and should be explored in NSCLC patients

Décrire le parcours de soins des femmes prises en charge pour un cancer du sein: identifier les parcours « complexes »

International audienceObjectives: We studied both the independent and combined effects of the places of biopsy and treatment on the treatment time interval based on a population-based study.Methods: We analysed the proportion of patients having a treatment time interval higher than the EUSOMA recommendation of 6 weeks, as a function of the number and the type of care centres the patients attended, from a French population-based regional cohort of women treated in 2015 for an incident invasive non-metastatic cancer (n = 505).Results: About 33% [95% CI: 27; 38] of patients had a treatment time interval higher than 6 weeks. About 48% of the patients underwent their biopsy and their initial treatment in the different centres. Results from multivariable analyses supported the impact of the type and number of centres attended on the proportion of time intervals over 6 weeks. This proportion was higher among patients with biopsy and treatment in different centres and among patients treated in a university hospital.Conclusion: We pointed out the independent impact of the type and the number of care centres the patients attended, from biopsy to first treatment, on the treatment time interval, which is a well-known prognosis factor

Prognostic Impact of TP53 Mutations in Metastatic Nonsquamous Non–small-cell Lung Cancer

International audienceBackground: The prognostic impact of TP53 mutations in advanced or metastatic nonsquamous non-small-cell lung cancer (nsNSCLC) patients treated with chemotherapy and/or immune checkpoint inhibitors (ICI) remains unclear.Materials and methods: We retrospectively collected data from patients with nsNSCLC treated in the first line from January 2018 to May 2021. The patient was separated into 2 groups according to their TP53 mutation status (wt vs. mut). Survival was estimated through the Kaplan-Meier method and compared by log-rank test.Results: Of 220 patients included, 126 were in the mutTP53 group, and 94 were in the wtTP53wt group. Median OS (mOS) was not significantly different between the mutTP53 and wtTP53 groups [17.5 months (95% confidence interval (CI), 11.3-21.5) vs. 9.5 months (95% CI, 7.4-14.2), (P = .051)]. In subgroup analyses, the mutTP53 group treated with ICI had a significantly improved mOS compared to the wtTP53 group [(24.7 months (95% CI, 20.8-not reach) vs. 12.0 months (95% CI, 4.7-not reach), (P = .017)] and mPFS [(9.6 months (95% CI, 5.8-not reach) vs. 3.2 months (95% CI, 1.3-13.8) (P = .048)]. There was no difference in terms of mOS and mPFS between the mutTP53 and the wtTP53 group treated by chemotherapy alone or combined with ICI.Conclusion: TP53 mutation had no survival impact in the overall population, but is associated with better outcomes with ICI alone. These results suggest that patients with TP53 mutations could be treated with ICI alone, and wild-type patients could benefit from the addition of chemotherapy

Baseline tumour size is an independent prognostic factor for overall survival in PD-L1 ≥ 50% non-small cell lung cancer patients treated with first-line pembrolizumab

International audienceBackground: Advanced non-small cell lung cancer (NSCLC) with a PD-L1 tumour proportion score ≥ 50% can be treated with pembrolizumab alone. Our aim was to assess the impact of baseline tumour size (BTS) on overall survival (OS) in NSCLC patients treated with pembrolizumab versus chemotherapy.Methods: This retrospective, multicentre study included all patients with untreated advanced NSCLC receiving either pembrolizumab (PD-L1 ≥ 50%) or platinum-based chemotherapy (any PD-L1). The primary endpoint was the impact of BTS (defined as the sum of the dimensions of baseline target lesions according to RECIST v1.1 criteria) on OS.Results: Between 09-2016 and 06-2020, 188 patients were included, 96 in the pembrolizumab (P-group) and 92 in the chemotherapy group (CT-group). The median follow-up was 26.9 months (range 0.13-37.91) and 44.4 months (range 0.23-48.62), respectively, while the median BTS was similar, 85.5 mm (IQR 57.2-113.2) and 86.0 mm (IQR 53.0-108.5), respectively (p = 0.42). The median P-group OS was 18.2 months [95% CI 12.2-not reached (NR)] for BTS > 86 mm versus NR (95% CI 27.2-NR) for BTS ≤ 86 mm (p = 0.0026). A high BTS was associated with a shorter OS in univariate analyses (p = 0.009) as well as after adjustment on confounding factors (HR 2.16, [95% CI 1.01-4.65], p = 0.048). The CT-group OS was not statistically different between low and high BTS patients, in univariate and multivariate analyses (p = 0.411).Conclusions: After adjustment on major baseline clinical prognostic factors, BTS was an independent prognostic factor for OS in PD-L1 ≥ 50% advanced NSCLC patients treated first-line with pembrolizumab