[Targeted therapies and immunotherapies in melanoma: A temporal approach to achieve optimal responses]. / Thérapies ciblées et immunothérapies dans le mélanome - Une approche temporelle pour une réponse optimale.

Title: Thérapies ciblées et immunothérapies dans le mélanome - Une approche temporelle pour une réponse optimale. Abstract: Dans le cadre d'un partenariat avec médecine/sciences, et pour la cinquième année consécutive, des étudiants du module d'enseignement « Immunologie, virologie et cancer ¼ du Master Cancer de Lyon présentent une analyse d'articles scientifiques récents faisant état d'observations innovantes et importantes. Ce travail a été encadré par des chercheurs confirmés du Centre de Recherche en Cancérologie de Lyon (CRCL). Le master Cancer (université Claude Bernard Lyon1- VetAgroSup) accueille chaque année 40 étudiants en M1 et environ 80 en M2. Ce master dit « d'excellence ¼ (master international labellisé université de Lyon) assure aux étudiants de M1 une formation en cancérologie reposant sur un socle de base commun (biologie cellulaire, moléculaire, immunologie, bio-statistique, épidémiologie, recherche translationnelle, etc.). Cette formation repose sur une forte implication des chercheurs et enseignants-chercheurs du CRCL, ainsi que sur un partenariat fort avec plusieurs instituts, dont le MIT (Massachusetts Institute of Technology, Cambridge, États-Unis), l'université d'Harvard (Boston, États-Unis), l'université de Californie à San Diego (UCSD) (États-Unis), la university of City of London (UCL), le Beatson Institute de Glasgow (Royaume-Uni), les universités de Shanghai Jiao Tong (République populaire de Chine, RPC), de Tokyo et Tohoku (Japon), de Melbourne (Australie) et d'Auckland (Nouvelle-Zélande).

Pharmacological targeting of netrin-1 inhibits EMT in cancer.

Epithelial-to-mesenchymal transition (EMT) regulates tumour initiation, progression, metastasis and resistance to anti-cancer therapy1-7. Although great progress has been made in understanding the role of EMT and its regulatory mechanisms in cancer, no therapeutic strategy to pharmacologically target EMT has been identified. Here we found that netrin-1 is upregulated in a primary mouse model of skin squamous cell carcinoma (SCC) exhibiting spontaneous EMT. Pharmacological inhibition of netrin-1 by administration of NP137, a netrin-1-blocking monoclonal antibody currently used in clinical trials in human cancer (ClinicalTrials.gov identifier NCT02977195 ), decreased the proportion of EMT tumour cells in skin SCC, decreased the number of metastases and increased the sensitivity of tumour cells to chemotherapy. Single-cell RNA sequencing revealed the presence of different EMT states, including epithelial, early and late hybrid EMT, and full EMT states, in control SCC. By contrast, administration of NP137 prevented the progression of cancer cells towards a late EMT state and sustained tumour epithelial states. Short hairpin RNA knockdown of netrin-1 and its receptor UNC5B in EPCAM+ tumour cells inhibited EMT in vitro in the absence of stromal cells and regulated a common gene signature that promotes tumour epithelial state and restricts EMT. To assess the relevance of these findings to human cancers, we treated mice transplanted with the A549 human cancer cell line-which undergoes EMT following TGFß1 administration8,9-with NP137. Netrin-1 inhibition decreased EMT in these transplanted A549 cells. Together, our results identify a pharmacological strategy for targeting EMT in cancer, opening up novel therapeutic interventions for anti-cancer therapy.

Netrin-1 blockade inhibits tumour growth and EMT features in endometrial cancer.

Netrin-1 is upregulated in cancers as a protumoural mechanism1. Here we describe netrin-1 upregulation in a majority of human endometrial carcinomas (ECs) and demonstrate that netrin-1 blockade, using an anti-netrin-1 antibody (NP137), is effective in reduction of tumour progression in an EC mouse model. We next examined the efficacy of NP137, as a first-in-class single agent, in a Phase I trial comprising 14 patients with advanced EC. As best response we observed 8 stable disease (8 out of 14, 57.1%) and 1 objective response as RECIST v.1.1 (partial response, 1 out of 14 (7.1%), 51.16% reduction in target lesions at 6 weeks and up to 54.65% reduction during the following 6 months). To evaluate the NP137 mechanism of action, mouse tumour gene profiling was performed, and we observed, in addition to cell death induction, that NP137 inhibited epithelial-to-mesenchymal transition (EMT). By performing bulk RNA sequencing (RNA-seq), spatial transcriptomics and single-cell RNA-seq on paired pre- and on-treatment biopsies from patients with EC from the NP137 trial, we noted a net reduction in tumour EMT. This was associated with changes in immune infiltrate and increased interactions between cancer cells and the tumour microenvironment. Given the importance of EMT in resistance to current standards of care2, we show in the EC mouse model that a combination of NP137 with carboplatin-paclitaxel outperformed carboplatin-paclitaxel alone. Our results identify netrin-1 blockade as a clinical strategy triggering both tumour debulking and EMT inhibition, thus potentially alleviating resistance to standard treatments.