Optimising urinary catecholamine metabolite diagnostics for neuroblastoma.

INTRODUCTION: The analysis of urinary catecholamine metabolites is a cornerstone of neuroblastoma diagnostics. Currently, there is no consensus regarding the sampling method, and variable combinations of catecholamine metabolites are being used. We investigated if spot urine samples can be reliably used for analysis of a panel of catecholamine metabolites for the diagnosis of neuroblastoma. METHODS: Twenty-four-hour urine or spot urine samples were collected from patients with and without neuroblastoma at diagnosis. Homovanillic acid (HVA), vanillylmandelic acid (VMA), dopamine, 3-methoxytyramine, norepinephrine, normetanephrine, epinephrine and metanephrine were measured by high-performance liquid chromatography coupled with fluorescence detection (HPLC-FD) and/or ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry (UPLC-MS/MS). RESULTS: Catecholamine metabolite levels were measured in urine samples of 400 neuroblastoma patients (24-hour urine, n = 234; spot urine, n = 166) and 571 controls (all spot urine). Excretion levels of catecholamine metabolites and the diagnostic sensitivity for each metabolite were similar in 24-hour urine and spot urine samples (p > .08 and >.27 for all metabolites). The area under the receiver-operating-characteristic curve (AUC) of the panel containing all eight catecholamine metabolites was significantly higher compared to that of only HVA and VMA (AUC = 0.952 vs. 0.920, p = .02). No differences were observed in metabolite levels between the two analysis methods. CONCLUSION: Catecholamine metabolites in spot urine and 24-hour urine resulted in similar diagnostic sensitivities. The Catecholamine Working Group recommends the implementation of spot urine as standard of care. The panel of eight catecholamine metabolites has superior diagnostic accuracy over VMA and HVA.

Mutational spectrum of ATRX aberrations in neuroblastoma and associated patient and tumor characteristics.

Neuroblastoma is the most common extracranial solid tumor in children. The chromatin remodeler ATRX is frequently mutated in high-risk patients with a poor prognosis. Although many studies have reported ATRX aberrations and the associated clinical characteristics in neuroblastoma, a comprehensive overview is currently lacking. In this study, we extensively characterize the mutational spectrum of ATRX aberrations in neuroblastoma tumors reported in previous studies and present an overview of patient and tumor characteristics. We collected the data of a total of 127 neuroblastoma patients and three cell lines with ATRX aberrations originating from 20 papers. We subdivide the ATRX aberrations into nonsense, missense, and multiexon deletions (MEDs) and show that 68% of them are MEDs. Of these MEDs, 75% are predicted to be in-frame. Furthermore, we identify a missense mutational hotspot region in the helicase domain. We also confirm that all three ATRX mutation types are more often identified in patients diagnosed at an older age, but still approximately 40% of the patients are aged 5 years or younger at diagnosis. Surprisingly, we found that 11q deletions are enriched in neuroblastomas with ATRX deletions compared to a reference cohort, but not in neuroblastomas with ATRX point mutations. Taken together, our data emphasizes a distinct ATRX mutation spectrum in neuroblastoma, which should be considered when studying molecular phenotypes and therapeutic strategies.

Transmission of breast cancer by a single multiorgan donor to 4 transplant recipients.

We report 4 cases of breast cancer transmission to transplant recipients from a single organ donor that occurred years after donation. The diagnosis of breast cancer was occult at the time of donation. All of the recipients developed a histologically similar type of breast cancer within 16 months to 6 years after transplantation. Three out of 4 recipients died as a result of widely metastasized disease. One of the recipients survived after transplant nephrectomy followed by cessation of immunosuppression and chemotherapy. This extraordinary case points out the often fatal consequences of donor-derived breast cancer and suggests that removal of the donor organ and restoration of immunity can induce complete remission.

Integrative analysis of neuroblastoma by single-cell RNA sequencing identifies the NECTIN2-TIGIT axis as a target for immunotherapy.

Pediatric patients with high-risk neuroblastoma have poor survival rates and urgently need more effective treatment options with less side effects. Since novel and improved immunotherapies may fill this need, we dissect the immunoregulatory interactions in neuroblastoma by single-cell RNA-sequencing of 24 tumors (10 pre- and 14 post-chemotherapy, including 5 pairs) to identify strategies for optimizing immunotherapy efficacy. Neuroblastomas are infiltrated by natural killer (NK), T and B cells, and immunosuppressive myeloid populations. NK cells show reduced cytotoxicity and T cells have a dysfunctional profile. Interaction analysis reveals a vast immunoregulatory network and identifies NECTIN2-TIGIT as a crucial immune checkpoint. Combined blockade of TIGIT and PD-L1 significantly reduces neuroblastoma growth, with complete responses (CR) in vivo. Moreover, addition of TIGIT+PD-L1 blockade to standard relapse treatment in a chemotherapy-resistant Th-ALKF1174L/MYCN 129/SvJ syngeneic model induces CR. In conclusion, our integrative analysis provides promising targets and a rationale for immunotherapeutic combination strategies.

Urinary 3-Methoxytyramine Is a Biomarker for MYC Activity in Patients With Neuroblastoma.

PURPOSE: Elevated urinary 3-methoxytyramine (3MT) level at diagnosis was recently put forward as independent risk factor for poor prognosis in neuroblastoma. Here, we investigated the biologic basis underlying the putative association between elevated 3MT levels and poor prognosis. METHODS: Urinary 3MT levels and prognosis were investigated in both retrospective Italian (N = 90) and prospective Dutch (N = 95) cohorts. From the Dutch Cancer Oncology Group cohort (N = 122), patients with available urinary 3MT and gene expression data (n = 90) were used to generate a 3MT gene signature. The 3MT gene signature score was then used to predict survival outcome in the Children's Oncology Group (N = 247) and German Pediatric Oncology Group (N = 498) cohorts and compared with other known gene signatures. Immunohistochemistry of MYCN and dopamine ß-hydroxylase proteins was performed on primary tumors. RESULTS: Elevated urinary 3MT levels were associated with poor prognosis in a retrospective cohort and a prospective cohort. Moreover, elevated urinary 3MT levels were associated with eight differentially expressed genes, providing a 3MT gene signature that successfully predicted poor clinical outcome. Even among low-risk patients, high 3MT signature score was associated with poor 5-year overall survival (72% v 99% among low-risk patients with a low 3MT signature score), and the 3MT signature score was correlated with MYC activity in the tumor (R = 82%, P < .0001). Finally, a strong MYCN and weak dopamine ß-hydroxylase staining of tumors derived from patients with elevated urinary 3MT levels was observed, linking MYC activity in the tumor to both catecholamine biosynthesis and elevated urinary 3MT levels. CONCLUSION: Elevated urinary 3MT is a promising biomarker for poor prognosis and reflects increased MYC activity in the tumor. Therefore, urinary 3MT levels should be measured at diagnosis and may assist in assessing risk.