Study of disseminated high-risk neuroblastoma in the bone marrow niche; from microenvironmental modelling to therapeutic targeting

[eng] Neuroblastoma (NB) is the most common extracraneal solid tumor diagnosed in the first 5 years of childhood and accounts for approximately 15% of all pediatric cancer-related deaths. At the time of diagnosis, about half of NB patients present disseminated disease, being the bone marrow (BM) the most common site of dissemination. The persistence of infiltrated BM during treatment or relapse is predictive of patient poor outcome. The BM microenvironment has unique biologic properties that favor progression of disseminated NB tumor cells. In this environment, the receptor CXCR4 has a pivotal role for BM homeostasis and is involved in metastatic dissemination in several cancers. In NB, CXCR4 is expressed in tumor cells; however, its oncogenic role in relation with its ligand CXCL12 has shown contradictory results. Using an in vitro model that recapitulates low oxygen levels and chemokine signaling present in the BM environment, we explored whether CXCR4 together with MIF, a second ligand, is critical for NB survival and proliferation in the niche. We also evaluated MIF inhibition as a therapeutic option for NB. To develop a BM-based in vitro model, NB cells were cultured in different conditioned media (CMs) derived from supernatants of patient-derived BM primary cells (CM-BM) and NB cell lines (CM-NB) cultured alone, or in combination (CM-BM/NB). To mimic BM oxygen levels, NB cells were cultured under hypoxia (1% O2), as compared to cell culture normoxia (21% O2). Expanded BM cultures used to generate CMs contained a heterogenic population with a predominant cellularity positive for mesenchymal stromal markers measured by flow cytometry. Cytokine arrays and ELISA assays of CMs revealed MIF as the highest NB released cytokine, whereas CXCL12 was not detected. The expression of MIF and CXCL12 signaling pathways was analyzed with different public NB databases. Among the analyzed genes, the high expression of CXCR4 and MIF was associated with patient poor outcome and high-risk disseminated staging. To further explore the role of CXCR4/MIF axis in high- risk disseminated NB, in vitro and in vivo functional studies were performed with or without the covalent MIF inhibitor 4-IPP and the CXCR4 antagonist AMD3100. When exposed to BM-derived CMs and hypoxia, BM-derived NB cell lines showed increased surface expression of CXCR4 by flow cytometry. The same culture condition increased phosphorylated levels of AKT/PI3K and ERK/MAPK measured by western blot. Cell viability assays showed that hypoxic conditions and BM-derived CMs enhanced NB cell proliferation at different time points. Similarly, in vivo, the co-injection of BM cells favored NB tumor progression by reducing engraftment times in contrast to NB injection alone. Using wound healing assays and Matrigel-coated Transwells, CM-BM/NB chemoattracted and enhanced migration and invasion of LAN-1 cells cultured under hypoxic conditions. These aggressive phenotypes promoted by the BM-based model were reverted by adding sub-lethal concentrations of the MIF inhibitor 4-IPP. We also explored whether MIF present in our CMs affected response to chemotherapy. After treatment with doxorubicin and etoposide at IC50 values LAN-1 cell viability increased in CM-BM/NB compared to control media. In both cases, chemo-sensitivity was restored when 4-IPP was added to CM-BM/NB. Finally, the administration of 4-IPP delayed the tumor progression and increased mice survival in a LAN- 1 subcutaneous xenograft model. In conclusion, our findings provide new understanding of the contribution of BM microenvironment to NB progression. Based on our BM-model, the relationship between the BM microenvironment and NB cells appears mediate, in part, by the autocrine CXCR4/MIF signaling axis. Furthermore, our results suggested that MIF could represent a therapeutic target for the treatment of patients with high-risk NB

Effects of Hyperoxia on Oxygen-Related Inflammation with a Focus on Obesity

Several studies have shown a pathological oxygenation (hypoxia/hyperoxia) on the adipose tissue in obese subjects. Additionally, the excess of body weight is often accompanied by a state of chronic low-degree inflammation. The inflammation phenomenon is a complex biological response mounted by tissues to combat injurious stimuli in order to maintain cell homeostasis. Furthermore, it is believed that the abnormal oxygen partial pressure occurring in adipose tissue is involved in triggering inflammatory processes. In this context, oxygen is used in modern medicine as a treatment for several diseases with inflammatory components. Thus, hyperbaric oxygenation has demonstrated beneficial effects, apart from improving local tissue oxygenation, on promoting angiogenesis, wound healing, providing neuroprotection, facilitating glucose uptake, appetite, and others. Nevertheless, an excessive hyperoxia exposure can lead to deleterious effects such as oxidative stress, pulmonary edema, and maybe inflammation. Interestingly, some of these favorable outcomes occur under high and low oxygen concentrations. Hereby, we review a potential therapeutic approach to the management of obesity as well as the oxygen-related inflammation accompanying expanded adipose tissue, based on elevated oxygen concentrations. To conclude, we highlight at the end of this review some areas that need further clarification

MIF/CXCR4 signaling axis contributes to survival, invasion, and drug resistance of metastatic neuroblastoma cells in the bone marrow microenvironment

Background: The bone marrow (BM) is the most common site of dissemination in patients with aggressive, metastatic neuroblastoma (NB). However, the molecular mechanisms underlying the aggressive behavior of NB cells in the BM niche are still greatly unknown. In the present study, we explored biological mechanisms that play a critical role in NB cell survival and progression in the BM and investigated potential therapeutic targets. Methods: Patient-derived bone marrow (BM) primary cultures were generated using fresh BM aspirates obtained from NB patients. NB cell lines were cultured in the presence of BM conditioned media containing cell-secreted factors, and under low oxygen levels (1% O2) to mimic specific features of the BM microenvironment of high-risk NB patients. The BM niche was explored using cytokine profiling assays, cell migration-invasion and viability assays, flow cytometry and analysis of RNA-sequencing data. Selective pharmacological inhibition of factors identified as potential mediators of NB progression within the BM niche was performed in vitro and in vivo. Results: We identified macrophage migration inhibitory factor (MIF) as a key inflammatory cytokine involved in BM infiltration. Cytokine profiling and RNA-sequencing data analysis revealed NB cells as the main source of MIF in the BM, suggesting a potential role of MIF in tumor invasion. Exposure of NB cells to BM-conditions increased NB cell-surface expression of the MIF receptor CXCR4, which was associated with increased cell viability, enhanced migration-invasion, and activation of PI3K/AKT and MAPK/ERK signaling pathways. Moreover, subcutaneous co-injection of NB and BM cells enhanced tumor engraftment in mice. MIF inhibition with 4-IPP impaired in vitro NB aggressiveness, and improved drug response while delayed NB growth, improving survival of the NB xenograft model. Conclusions: Our findings suggest that BM infiltration by NB cells may be mediated, in part, by MIF-CXCR4 signaling. We demonstrate the antitumor efficacy of MIF targeting in vitro and in vivo that could represent a novel therapeutic target for patients with disseminated high-risk NB

Effects of hyperoxia on oxygen-related inflammation with a focus on obesity

Several studies have shown a pathological oxygenation (hypoxia/hyperoxia) on the adipose tissue in obese subjects. Additionally, the excess of body weight is often accompanied by a state of chronic low-degree inflammation.The inflammation phenomenon is a complex biological response mounted by tissues to combat injurious stimuli in order to maintain cell homeostasis. Furthermore, it is believed that the abnormal oxygen partial pressure occurring in adipose tissue is involved in triggering inflammatory processes. In this context, oxygen is used in modern medicine as a treatment for several diseases with inflammatory components. Thus, hyperbaric oxygenation has demonstrated beneficial effects, apart from improving local tissue oxygenation, on promoting angiogenesis, wound healing, providing neuroprotection, facilitating glucose uptake, appetite, and others. Nevertheless, an excessive hyperoxia exposure can lead to deleterious effects such as oxidative stress, pulmonary edema, and maybe inflammation. Interestingly, some of these favorable outcomes occur under high and low oxygen concentrations. Hereby, we review a potential therapeutic approach to the management of obesity as well as the oxygen-related inflammation accompanying expanded adipose tissue, based on elevated oxygen concentrations. To conclude, we highlight at the end of this review some areas that need further clarification

Effects of hyperoxia on oxygen-related inflammation with a focus on obesity

Several studies have shown a pathological oxygenation (hypoxia/hyperoxia) on the adipose tissue in obese subjects. Additionally, the excess of body weight is often accompanied by a state of chronic low-degree inflammation.The inflammation phenomenon is a complex biological response mounted by tissues to combat injurious stimuli in order to maintain cell homeostasis. Furthermore, it is believed that the abnormal oxygen partial pressure occurring in adipose tissue is involved in triggering inflammatory processes. In this context, oxygen is used in modern medicine as a treatment for several diseases with inflammatory components. Thus, hyperbaric oxygenation has demonstrated beneficial effects, apart from improving local tissue oxygenation, on promoting angiogenesis, wound healing, providing neuroprotection, facilitating glucose uptake, appetite, and others. Nevertheless, an excessive hyperoxia exposure can lead to deleterious effects such as oxidative stress, pulmonary edema, and maybe inflammation. Interestingly, some of these favorable outcomes occur under high and low oxygen concentrations. Hereby, we review a potential therapeutic approach to the management of obesity as well as the oxygen-related inflammation accompanying expanded adipose tissue, based on elevated oxygen concentrations. To conclude, we highlight at the end of this review some areas that need further clarification

GPC2 antibody–drug conjugate reprograms the neuroblastoma immune milieu to enhance macrophage-driven therapies

Background Antibody–drug conjugates (ADCs) that deliver cytotoxic drugs to tumor cells have emerged as an effective and safe anticancer therapy. ADCs may induce immunogenic cell death (ICD) to promote additional endogenous antitumor immune responses. Here, we characterized the immunomodulatory properties of D3-GPC2-PBD, a pyrrolobenzodiazepine (PBD) dimer-bearing ADC that targets glypican 2 (GPC2), a cell surface oncoprotein highly differentially expressed in neuroblastoma.Methods ADC-mediated induction of ICD was studied in GPC2-expressing murine neuroblastomas in vitro and in vivo. ADC reprogramming of the neuroblastoma tumor microenvironment was profiled by RNA sequencing, cytokine arrays, cytometry by time of flight and flow cytometry. ADC efficacy was tested in combination with macrophage-driven immunoregulators in neuroblastoma syngeneic allografts and human patient-derived xenografts.Results The D3-GPC2-PBD ADC induced biomarkers of ICD, including neuroblastoma cell membrane translocation of calreticulin and heat shock proteins (HSP70/90) and release of high-mobility group box 1 and ATP. Vaccination of immunocompetent mice with ADC-treated murine neuroblastoma cells promoted T cell-mediated immune responses that protected animals against tumor rechallenge. ADC treatment also reprogrammed the tumor immune microenvironment to a proinflammatory state in these syngeneic neuroblastoma models, with increased tumor trafficking of activated macrophages and T cells. In turn, macrophage or T-cell inhibition impaired ADC efficacy in vivo, which was alternatively enhanced by both CD40 agonist and CD47 antagonist antibodies. In human neuroblastomas, the D3-GPC2-PBD ADC also induced ICD and promoted tumor phagocytosis by macrophages, which was further enhanced when blocking CD47 signaling in vitro and in vivo.Conclusions We elucidated the immunoregulatory properties of a GPC2-targeted ADC and showed robust efficacy of combination immunotherapies in diverse neuroblastoma preclinical models

Therapeutic targeting of the RB1 pathway in retinoblastoma with the oncolytic adenovirus VCN-01

Retinoblastoma is a pediatric solid tumor of the retina activated upon homozygous inactivation of the tumor suppressor RB1. VCN-01 is an oncolytic adenovirus designed to replicate selectively in tumor cells with high abundance of free E2F-1, a consequence of a dysfunctional RB1 pathway. Thus, we reasoned that VCN-01 could provide targeted therapeutic activity against even chemoresistant retinoblastoma. In vitro, VCN-01 effectively killed patient-derived retinoblastoma models. In mice, intravitreous administration of VCN-01 in retinoblastoma xenografts induced tumor necrosis, improved ocular survival compared with standard-of-care chemotherapy, and prevented micrometastatic dissemination into the brain. In juvenile immunocompetent rabbits, VCN-01 did not replicate in retinas, induced minor local side effects, and only leaked slightly and for a short time into the blood. Initial phase 1 data in patients showed the feasibility of the administration of intravitreous VCN-01 and resulted in antitumor activity in retinoblastoma vitreous seeds and evidence of viral replication markers in tumor cells. The treatment caused local vitreous inflammation but no systemic complications. Thus, oncolytic adenoviruses targeting RB1 might provide a tumor-selective and chemotherapy-independent treatment option for retinoblastoma.Fil: Pascual-Pasto, Guillem. Hospital Sant Joan de Déu; EspañaFil: Bazan-Peregrino, Miriam. No especifíca;Fil: Olaciregui, Nagore G.. Hospital Sant Joan de Déu; EspañaFil: Restrepo Perdomo, Camilo A.. Hospital Sant Joan de Déu; EspañaFil: Mato Berciano, Ana. No especifíca;Fil: Ottaviani, Daniela. Centre National de la Recherche Scientifique; FranciaFil: Weber, Klaus. No especifíca;Fil: Correa, Genoveva. Hospital Sant Joan de Déu; EspañaFil: Paco, Sonia. Hospital Sant Joan de Déu; EspañaFil: Vila Ubach, Monica. Hospital Sant Joan de Déu; EspañaFil: Cuadrado Vilanova, Maria. Hospital Sant Joan de Déu; EspañaFil: Castillo Ecija, Helena. Hospital Sant Joan de Déu; EspañaFil: Botteri, Gaia. Hospital Sant Joan de Déu; EspañaFil: Garcia Gerique, Laura. Hospital Sant Joan de Déu; EspañaFil: Moreno Gilabert, Helena. Hospital Sant Joan de Déu; EspañaFil: Gimenez Alejandre, Marta. No especifíca;Fil: Alonso Lopez, Patricia. No especifíca;Fil: Farrera Sal, Marti. No especifíca;Fil: Torres Manjon, Silvia. Instituto de Investigación Biomédica de Bellvitge; EspañaFil: Ramos Lozano, Dolores. Instituto de Investigación Biomédica de Bellvitge; EspañaFil: Moreno, Rafael. Instituto de Investigación Biomédica de Bellvitge; EspañaFil: Aerts, Isabelle. Centre National de la Recherche Scientifique; FranciaFil: Doz, François. Universite Paris Descartes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Cassoux, Nathalie. Centre National de la Recherche Scientifique; Francia. Universite Paris Descartes; FranciaFil: Chapeaublanc, Elodie. Centre National de la Recherche Scientifique; FranciaFil: Torrebadell, Montserrat. Hospital Sant Joan de Déu; EspañaFil: Roldan, Monica. Hospital Sant Joan de Déu; EspañaFil: König, Andrés. No especifíca;Fil: Suñol, Mariona. Hospital Sant Joan de Déu; EspañaFil: Claverol, Joana. Hospital Sant Joan de Déu; EspañaFil: Lavarino, Cinzia. Hospital Sant Joan de Déu; EspañaFil: De Torres, Carmen. Hospital Sant Joan de Déu; EspañaFil: Fu, Ligia. Hospital Escuela Universitario; HondurasFil: Radvanyi, François. Centre National de la Recherche Scientifique; FranciaFil: Munier, Francis L.. Hopital Ophtalmique Jules Gonin; SuizaFil: Catalá-Mora, Jaume. Hospital Sant Joan de Déu; EspañaFil: Mora, Jaume. Hospital Sant Joan de Déu; EspañaFil: Alemany, Ramón. Instituto de Investigación Biomédica de Bellvitge; EspañaFil: Cascalló, Manel. No especifíca;Fil: Chantada, Guillermo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; ArgentinaFil: Montero Carcaboso, Angel. Hospital Sant Joan de Déu; Españ