Anti-GD2 antibody-containing immunotherapy postconsolidation therapy for people with high-risk neuroblastoma treated with autologous haematopoietic stem cell transplantation

Advances in CAR T cell immunotherapy for paediatric brain tumours

Brain tumours are the most common solid tumour in children and the leading cause of cancer related death in children. Current treatments include surgery, chemotherapy and radiotherapy. The need for aggressive treatment means many survivors are left with permanent severe disability, physical, intellectual and social. Recent progress in immunotherapy, including genetically engineered T cells with chimeric antigen receptors (CARs) for treating cancer, may provide new avenues to improved outcomes for patients with paediatric brain cancer. In this review we discuss advances in CAR T cell immunotherapy, the major CAR T cell targets that are in clinical and pre-clinical development with a focus on paediatric brain tumours, the paediatric brain tumour microenvironment and strategies used to improve CAR T cell therapy for paediatric tumours.

Molecular Basis and Clinical Features of Neuroblastoma

Neuroblastoma, a neoplasm of the sympathetic nervous system, originates from neuroblastoma stem cells during embryogenesis. It exhibits unique clinical features including a tendency for spontaneous regression of tumors in infants and a high frequency of metastatic disease at diagnosis in patients aged over 18 months. Genetic risk factors and epigenetic dysregulation also play a significant role in the development of neuroblastoma. Over the past decade, our understanding of this disease has advanced considerably. This has included the identification of chromosomal copy number aberrations specific to neuroblastoma development, risk groups, and disease stage. However, high-risk neuroblastoma remains a therapeutic challenge for pediatric oncologists. New therapeutic approaches have been developed, either as alternatives to conventional chemotherapy or in combination, to overcome the dismal prognosis. Particularly promising strategies are targeted therapies that directly affect cancer cells or cancer stem cells while exhibiting minimal effect on healthy cells. This review summarizes our understanding of neuroblastoma biology and prognostic features and focuses on novel therapeutic strategies for this intractable disease.

Characterization of glycosphingolipids from gastrointestinal stromal tumours

Gastrointestinal stromal tumours (GISTs) are the major nonepithelial neoplasms of the human gastrointestinal tract with a worldwide incidence between 11 and 15 per million cases annually. In this study the acid and non-acid glycosphingolipids of three GISTs were characterized using a combination of thin-layer chromatography, chemical staining, binding of carbohydrate recognizing ligands, and mass spectrometry. In the non-acid glycosphingolipid fractions of the tumors globotetraosylceramide, neolactotetraosylceramide, and glycosphingolipids with terminal blood group A, B, H, Le^x, Le^a, Le^y and Le^b determinants were found. The relative amounts of these non-acid compounds were different in the three tumour samples. The acid glycosphingolipid fractions had sulfatide, and the gangliosides GM3, GD3, GM1, Neu5Acα3neolactotetraosylceramide, GD1a, GT1b and GQ1b. In summary, we have characterized the glycosphingolipids of GISTs and found that the pattern differs in tumours from different individuals. This detailed characterization of glycosphingolipid composition of GISTs could contribute to recognition of new molecular targets for GIST treatment and sub-classification.

Disialoganglioside GD2 Expression in Solid Tumors and Role as a Target for Cancer Therapy

Gangliosides are carbohydrate-containing sphingolipids that are widely expressed in normal tissues, making most subtypes unsuitable as targets for cancer therapy. However, the disialoganglioside GD2 subtype has limited expression in normal tissues but is overexpressed across a wide range of tumors. Disialoganglioside GD2 can be considered a tumor-associated antigen and well-suited as a target for cancer therapy. Disialoganglioside GD2 is implicated in tumor development and malignant phenotypes through enhanced cell proliferation, motility, migration, adhesion, and invasion, depending on the tumor type. This provides a rationale for targeting disialoganglioside GD2 in cancer therapy with the development of anti-GD2 monoclonal antibodies and other therapeutic approaches. Anti-GD2 monoclonal antibodies target GD2-expressing tumor cells, leading to phagocytosis and destruction by means of antibody-dependent cell-mediated cytotoxicity, lysis by complement-dependent cytotoxicity, and apoptosis and necrosis through direct induction of cell death. Anti-GD2 monoclonal antibodies may also prevent homing and adhesion of circulating malignant cells to the extracellular matrix. Disialoganglioside GD2 is highly expressed by almost all neuroblastomas, by most melanomas and retinoblastomas, and by many Ewing sarcomas and, to a more variable degree, by small cell lung cancer, gliomas, osteosarcomas, and soft tissue sarcomas. Successful treatment of disialoganglioside GD2-expressing tumors with anti-GD2 monoclonal antibodies is hindered by pharmacologic factors such as insufficient antibody affinity to mediate antibody-dependent cell-mediated cytotoxicity, inadequate penetration of antibody into the tumor microenvironment, and toxicity related to disialoganglioside GD2 expression by normal tissues such as peripheral sensory nerve fibers. Nonetheless, anti-GD2 monoclonal antibody dinutuximab (ch14.18) has been approved by the U.S. Food and Drug Administration and dinutuximab beta (ch14.18/CHO) has been approved by the European Medicines Agency for the treatment of high-risk neuroblastoma in pediatric patients. Clinical trials of anti-GD2 therapy are currently ongoing in patients with other types of disialoganglioside GD2-expressing tumors as well as neuroblastoma. In addition to anti-GD2 monoclonal antibodies, anti-GD2 therapeutic approaches include chimeric antigen receptor T-cell therapy, disialoganglioside GD2 vaccines, immunocytokines, immunotoxins, antibody-drug conjugates, radiolabeled antibodies, targeted nanoparticles, and T-cell engaging bispecific antibodies. Clinical trials should clarify further the potential of anti-GD2 therapy for disialoganglioside GD2-expressing malignant tumors.

Development and Validation of an RNA-Seq-Based Prognostic Signature in Neuroblastoma

Objective: The stratification of neuroblastoma (NBL) prognosis remains difficult. RNA-based signatures might be able to predict prognosis, but independent cross-platform validation is still rare.

Methods: RNA-Seq-based profiles from NBL patients were acquired and then analyzed. The RNA-Seq prognostic index (RPI) and the clinically adjusted RPI (RCPI) were successively established in the training cohort (TARGET-NBL) and then verified in the validation cohort (GSE62564). Survival prediction was assessed using a time-dependent receiver operating characteristic (ROC) curve and area under the ROC curve (AUC). Functional enrichment analysis of the genes was conducted using bioinformatics methods.

Results: In the training cohort, 10 gene pairs were eventually integrated into the RPI. In both cohorts, the high-risk group had poor overall survival (OS) (P < 0.001 and P < 0.001, respectively) and favorable event-free survival (EFS) (P = 0.00032 and P = 0.06, respectively). ROC curve analysis also showed that the RPI predicted OS (60 month AUC values of 0.718 and 0.593, respectively) and EFS (60 month AUC values of 0.627 and 0.852, respectively) well in both the training and validation cohorts. Clinicopathological indicators associated with prognosis in the univariate and multivariate regression analyses were identified and added to the RPI to form the RCPI. The RCPI was also used to divide populations into different risk groups, and the high-risk group had poor OS (P < 0.001 and P < 0.001, respectively) and EFS (P < 0.05 and P < 0.05, respectively). Finally, the RCPI had higher accuracy than the RPI for the prediction of OS (60 month AUC values of 0.730 and 0.852, respectively) and EFS (60 month AUC values of 0.663 and 0.763, respectively) in both the training and validation cohorts. Moreover, these differentially expressed genes may be involved in certain NBL-related events.

Conclusions: The RCPI could reliably categorize NBL patients based on different risks of death.

Anti-GD2 antibody-containing immunotherapy postconsolidation therapy for people with high-risk neuroblastoma treated with autologous haematopoietic stem cell transplantation

BACKGROUND

Neuroblastoma is a rare malignant disease that primarily affects children. The tumours mainly develop in the adrenal medullary tissue, and an abdominal mass is the most common presentation. High-risk disease is characterised by metastasis and other primary tumour characteristics resulting in increased risk for an adverse outcome. The GD2 carbohydrate antigen is expressed on the cell surface of neuroblastoma tumour cells and is thus a promising target for anti-GD2 antibody-containing immunotherapy.

OBJECTIVES

To assess the efficacy of anti-GD2 antibody-containing postconsolidation immunotherapy after high-dose chemotherapy (HDCT) and autologous haematopoietic stem cell transplantation (HSCT) compared to standard therapy after HDCT and autologous HSCT in people with high-risk neuroblastoma. Our primary outcomes were overall survival and treatment-related mortality. Our secondary outcomes were progression-free survival, event-free survival, early toxicity, late non-haematological toxicity, and health-related quality of life.

SEARCH METHODS

We searched the electronic databases CENTRAL (2018, Issue 9), MEDLINE (PubMed), and Embase (Ovid) on 20 September 2018. We searched trial registries and conference proceedings on 28 October 2018. Further searches included reference lists of recent reviews and relevant articles as well as contacting experts in the field. There were no limits on publication year or language.

SELECTION CRITERIA

Randomised controlled trials evaluating anti-GD2 antibody-containing immunotherapy after HDCT and autologous HSCT in people with high-risk neuroblastoma.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, abstracted data on study and participant characteristics, and assessed risk of bias and GRADE. Any differences were resolved by discussion, with third-party arbitration unnecessary. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions. We used the five GRADE considerations, that is study limitations, consistency of effect, imprecision, indirectness, and publication bias, to judge the quality of the evidence.

MAIN RESULTS

We identified one randomised controlled trial that included 226 people with high-risk neuroblastoma who were pre-treated with autologous HSCT. The study randomised 113 participants to receive immunotherapy including isotretinoin, granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-2, and ch14.18, a type of anti-GD2 antibody also known as dinutuximab. The study randomised another 113 participants to receive standard therapy including isotretinoin.The results on overall survival favoured the dinutuximab-containing immunotherapy group (hazard ratio (HR) 0.50, 95% confidence interval (CI) 0.31 to 0.80; P = 0.004). The results on event-free survival also favoured the dinutuximab-containing immunotherapy group (HR 0.61, 95% CI 0.41 to 0.92; P = 0.020). Randomised data on adverse events were not reported separately. The study did not report progression-free survival, late non-haematological toxicity, and health-related quality of life as separate endpoints. We graded the quality of the evidence as moderate.

AUTHORS' CONCLUSIONS

The evidence base favours dinutuximab-containing immunotherapy compared to standard therapy concerning overall survival and event-free survival in people with high-risk neuroblastoma pre-treated with autologous HSCT. Randomised data on adverse events are lacking, therefore more research is needed before definitive conclusions can be made regarding this outcome.