Giuseppe Di Feo

Immune thrombocytopenia (ITP) is the most common pediatric thrombocytopenia, characterized by immune-mediated platelet destruction and altered inflammatory responses. Among these alterations, mesenchymal stromal cells (MSCs) from ITP patients display reduced viability and impaired immunoregulatory functions. Our previous work revealed dysregulated iron metabolism in ITP-MSCs, with increased intracellular iron accumulation driven by hepcidin–FPN1 axis disruption and overexpression of iron importers. Given the link between iron overload, oxidative stress, and ferroptosis, a regulated iron-dependent form of cell death, we investigated whether ITP-MSCs exhibit oxidative and molecular alterations associated with ferroptosis. ITP-MSCs showed increased ROS levels and ACSL4 expression, together with reduced expression of proteins involved in ferroptosis-related antioxidant defense, including SLC3A2, SLC7A11, and GPX4. Increased extracellular release of HMGB1, a DAMP associated with cellular stress and different forms of regulated cell death, was also observed. Treatment with Ferrostatin-1 (Fer-1) and Deferasirox (DFX) reduced oxidative stress and partially restored the expression of ferroptosis-related markers. Similarly, high-dose dexamethasone (HD-Dexa) reduced ROS and ACSL4 levels and limited extracellular HMGB1 release. Collectively, these findings support increased susceptibility to ferroptotic stress in ITP-MSCs and reveal a ferroptosis-associated oxidative stress phenotype with concomitant alterations in ferroptosis-related molecular pathways. Moreover, the effects of HD-Dexa, DFX, and Fer-1 suggest that modulation of these pathways may represent a potential strategy for limiting oxidative cellular damage in ITP-MSCs.

Ferroptosis is a regulated form of cell death caused by iron-dependent membrane lipid peroxidation. Iron metabolism, membrane lipid composition, cellular metabolic pathways, and antioxidant defense systems regulate ferroptosis. Recently, ferroptosis has attracted interest as a target in cancer therapy, in particular cancer cells have developed several biological adaptative mechanisms to evade ferroptosis, thus enhancing tumor progression, metastatic dissemination, stemness, and resistance to conventional therapies. Interestingly, ferroptosis is regulated by the tumor microenvironment, where hypoxia, immune cells, and stromal components can either stimulate or inhibit ferroptotic cell death. It has been demonstrated that targeting ferroptosis, alone or in combination with chemotherapy, radiotherapy and immunotherapy, has anticancer effects in preclinical models and may contribute to avoid treatment resistance. However, the role of ferroptosis in pediatric cancer remains incompletely understood since these kinds of tumors show different developmental, genomic, and metabolic features that may contribute to create different ferroptosis vulnerabilities. Emerging evidence in neuroblastoma, B-cell acute lymphoblastic leukemia, osteosarcoma, and medulloblastoma supports the involvement of ferroptosis-related pathways in tumor biology and treatment response. Preclinical studies also indicate that ferroptosis induction may represent a therapeutic strategy in selected pediatric cancer models, although tumor heterogeneity, drug delivery, and potential toxicity to developing tissues remain important translational challenges. This review summarizes the molecular mechanisms underlining the relationship between ferroptosis and cancer biology, tumor progression, tumor microenvironment, and therapy resistance, with particular interest in its emerging relevance and therapeutic potential in pediatric oncology, while critically considering the current evidence and major challenges for clinical translation.

OS is the most common primary malignant bone tumor, predominantly affecting children, adolescents, and young adults. Despite advances in multimodal treatment, patient outcomes have remained largely unchanged over the past decades, particularly in cases of metastatic or recurrent disease. Increasing evidence highlights the pivotal role of the tumor microenvironment (TME) in OS progression, metastasis, immune evasion, and therapeutic resistance. The OS TME comprises a complex and dynamic network of tumor cells, immune cells, cancer-associated fibroblasts, mesenchymal stromal cells, endothelial cells, extracellular matrix components, and soluble factors that collectively regulate tumor behavior. This review summarizes the current understanding of the OS TME, highlighting the interactions between malignant cells and their surrounding microenvironment and their contribution to tumor growth, angiogenesis, invasion, metastatic dissemination, and treatment response. Moreover, here we discuss the strengths and limitations of the most relevant preclinical models currently used to investigate OS biology and evaluate novel therapeutic strategies. Three-dimensional (3D) culture systems, including spheroids, organoids, and biomimetic scaffold-based models, today are considered the models able to best recapitulate the structural, mechanical, and cellular complexity of the native tumor microenvironment than conventional two-dimensional cultures. In addition, patient-derived xenograft (PDX) models are reviewed for their ability to preserve the histopathological, molecular, and genetic characteristics of the original tumors, making them valuable platforms for translational research, biomarker discovery, and personalized medicine.

Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy, characterized by the clonal proliferation of immature lymphoid precursors. The distinction between B-cell ALL (B-ALL) and T-cell ALL (T-ALL) is fundamental, as each subtype exhibits distinct cytomorphological, genetic, and clinical features influencing prognosis and therapeutic strategies. Conventional multi-phase chemotherapy has significantly improved survival rates, yet its efficacy is limited by severe short- and long-term toxicities, highlighting the need for more selective therapeutic approaches. Advances in molecular profiling have enabled the identification of key oncogenic pathways, paving the way for targeted therapies such as tyrosine kinase inhibitors (TKIs), JAK-STAT pathway inhibitors, BCL-2 antagonists, and agents modulating epigenetic and cell cycle regulators. Concurrently, immunotherapeutic strategies have transformed the therapeutic landscape of pediatric ALL. Bispecific antibodies such as blinatumomab (anti-CD19), antibody–drug conjugates like inotuzumab ozogamicin (anti-CD22), and monoclonal antibodies such as daratumumab (anti-CD38) have demonstrated efficacy in relapsed or refractory disease with improved safety profiles. Moreover, CAR-T-cell therapy, particularly CD19-directed products, has shown unprecedented remission rates in refractory B-ALL. The integration of targeted and immune-based therapies into conventional regimens represents a decisive step toward precision medicine, aiming to enhance survival outcomes while reducing treatment-related toxicity and improving quality of life in ALL children. This review aims to provide a comprehensive overview of the current understanding of ALL pathobiology and therapeutic approaches, with particular emphasis on the expanding role of immunotherapeutic strategies in pediatric disease.

Osteosarcoma (OS) is the most severe bone tumor in children. A chemotherapy regimen includes a combination of high-dose Methotrexate (MTX), doxorubicin, and cisplatin. These drugs cause acute and chronic side effects, such as infections, thrombocytopenia, neutropenia, DNA damage, and inflammation. Therefore, to identify new therapeutic strategies, effective and with a safety profile, is necessary. The Hedgehog (Hh) signaling pathway involved in tumorigenesis is active in OS. Hh components Patched receptor 1 (PTCH1), Smoothened (SMO), and glioma-associated oncogene homolog transcription factors (GLI1 and GLI2) are overexpressed in OS cell lines and patient samples. Curcumin (CUR)—with antioxidant and anti-cancer properties—downregulates Hh components in cancer, inhibiting progression. This study investigates CUR effects on the MG-63 OS cell line, alone and combined with MTX, to propose a novel therapeutic approach. Our study suggests CUR as a novel therapeutic agent in OS, particularly when combined with MTX. Targeting the Hh signaling pathway, CUR and MTX showed significant pro-apoptotic effects, increasing the BAX/Bcl-2 ratio and total apoptotic cell percentage. They reduced the expression of Hh pathway components (PTCH1, SMO, GLI1, and GLI2), inhibiting OS cell proliferation, survival, and invasion. CUR and MTX combined determined a β-Catenin decrease and a trend toward reducing NF-kB and matrix metalloproteinases (MMP-2 and MMP-9). Our findings suggest CUR as a support to OS treatment, improving outcomes and reducing the adverse effects of current therapies.

Hemoglobinopathies are monogenic disorders affecting hemoglobin synthesis. Thalassemia and sickle cell disease (SCD) are considered the two major hemoglobinopathies. Thalassemia is a genetic disorder and one of the major hemoglobinopathies determined by an impairment of globin chain production, which causes an alteration of erythropoiesis, an improvement in hemolysis, and an alteration of iron homoeostasis. In SCD, the mutations are on the β-globin chain of hemoglobin which results in a substitution of glutamic acid by valine with consequent formation of Hemoglobin S (HbS). Several factors are involved in bone metabolism alteration in patients with hemoglobinopathies, among them hormonal deficiency, bone marrow hyperplasia, iron overload, inflammation, and increased bone turnover. Bone metabolism is the result of balance maintenance between bone deposition and bone resorption, by osteoblasts (OBs) and osteoclasts (OCs). An impairment of this balance is responsible for the onset of bone diseases, such as osteoporosis (OP). Therefore, here we will discuss the alteration of bone metabolism in patients with hemoglobinopathies and the possible therapeutic strategies to contain and/or counteract bone health impairment in these patients, taking into consideration not only the pharmacological treatments already used in the clinical armamentarium, but also the new possible therapeutic strategies.

The advancement of anti-cancer therapies has markedly improved the survival rate of children with cancer, making them long-term childhood cancer survivors (CCS). Nevertheless, these treatments cause a low-grade inflammatory state, determining inflamm-aging and, thus, favoring the early onset of chronic diseases normally associated with old age. Identification of novel and safer therapeutic strategies is needed to counteract and prevent inflamm-aging. Macrophages are cells involved in immune and inflammatory responses, with a pivotal role in iron metabolism, which is related to inflammation. We obtained macrophages from CCS patients and evaluated their phenotype markers, inflammatory states, and iron metabolism by Western blotting, ELISA, and iron assays. We observed a strong increase in classically activated phenotype markers (M1) and iron metabolism alteration in CCS, with an increase in intracellular iron concentration and inflammatory markers. These results suggest that the prevalence of M1 macrophages and alteration of iron metabolism could be involved in the worsening of inflammation in CCS. Therefore, we propose macrophages and iron metabolism as novel therapeutic targets to counteract inflamm-aging. To avoid toxic regimens, we tested some nutraceuticals (resveratrol, curcumin, and oil-enriched lycopene), which are already known to exert anti-inflammatory properties. After their administration, we observed a macrophage switch towards the anti-inflammatory phenotype M2, as well as reductions in pro-inflammatory cytokines and the intracellular iron concentration. Therefore, we suggest—for the first time—that nutraceuticals reduce inflammation in CCS macrophages through a novel anti-inflammatory mechanism of action, modulating iron metabolism.