Identification of ALK Mutation in Neuroblastoma on the Point of Molecular Heterogeneity.

BACKGROUND AND AIM: In neuroblastoma, anaplastic lymphoma kinase mutations have recently received attention as molecular targets for the treatment of neuroblastoma, as 6% to 10% of patients with neuroblastoma have anaplastic lymphoma kinase mutations. There are little data from the cases in Turkey. We aimed to detect anaplastic lymphoma kinase mutations and molecular heterogeneity in neuroblastoma using next-generation sequencing. This study is the first one with this many cases in Turkey. METHODS: Next-generation sequencing analysis was performed using an Illumina MiniSeq custom gene panel. Clinically important mutations were selected for the analysis. We also gathered clinical data of the patients from Turkish Pediatric Oncology Group cohorts to associate them with anaplastic lymphoma kinase mutations. This study is a retrospective cross-sectional study. We followed STROBE guideline (https://www.equator-network.org/reporting-guidelines/strobe/) on this study. RESULTS: We analyzed anaplastic lymphoma kinase in 108 patients with neuroblastoma, with a mean age of 43.76 months. Pathogenic anaplastic lymphoma kinase mutations were detected in 13 patients (12.04%). We noted that anaplastic lymphoma kinase mutations were primarily observed in intermediate- and high-risk patients (P = .028). R1275Q and F1174-related mutations were predominant; I1171T, L1226F, S1189F, V1135A, and G1125S mutations were rare. Duplicate samples did not exhibit any heterogeneity. CONCLUSIONS: We found that F1174 and R1275Q-related anaplastic lymphoma kinase mutations are the most common pathogenic mutations in neuroblastoma. Anaplastic lymphoma kinase mutation status did not show any heterogeneity, and the mutations were correlated with intermediate- or high-risk groups.

Unraveling the Mystery: Next Generation Sequencing Sheds Light on Neuroblastoma Pathogenesis and Targeted Therapies.

BACKGROUND: There is considerable interest in the molecular evaluation of solid tumors in pediatric cases. Although clinical trials are in progress for targeted therapies against neuroblastoma (NB), novel therapeutic strategies are needed for high-risk cases that are resistant to therapy. The aim of the present study was to document the specific gene mutations related to targeted therapy in relapsed or refractory NB patients by using next generation sequencing (NGS). METHODS: The study included 57 NB patients from amongst 1965 neuroblastic cases in Turkey who experienced a recurrence after multi-model therapy. The cases were diagnosed, risk-stratified, and treated according to the classification system from the International Neuroblastoma Risk Group. Single nucleotide variations in 60 genes were investigated using the Pillar Onco/Reveal Multicancer v4 panel and Pillar RNA fusion panel on the Illumina Miniseq platform. RESULTS: ERBB2 I655V was the most frequent mutation and was found in 39.65% of cases. Anaplastic Lymphoma Kinase (ALK) mutations (F1174L, R1275Q, and rare mutations in the tyrosine kinase domain) were detected in 29.3% of cases. Fusion mutations in NTRK1, NTRK3, ROS1, RET, FGFR3, ALK and BRAF were observed in 19.6% of cases. CONCLUSIONS: This study presents valuable mutation data for relapsed and refractory NB patients. The high frequency of the ERBB2 I655V mutation may allow further exploration of this mutation as a potential therapeutic target. Rare BRAF mutations may also provide opportunities for targeted therapy. The role of ABL1 mutations in NB should also be explored further.

Comparison of Cytotoxic and Ototoxic Effects of Lipoplatin and Cisplatin in Neuroblastoma In Vivo Tumor Model.

BACKGROUND: This study aimed to compare the cytotoxic, cytostatic, and ototoxic effects of lipoplatin compared to cisplatin application in the subcutaneous xenograft nude mouse neuroblastoma tumor model. METHODS: In this study, C1300 neuroblastoma cells were administered subcutaneously to 21 male nude mice. When the tumor reached 150 mm3 diameter, mice were randomized into 3 groups. Saline, cisplatin, and lipoplatin were given intraperitoneally. The auditory function tests were performed before administration and 72 hours after administration. Mice were sacrificed and the tumor and cochlea were removed after 72 hours. Histopathologic evaluation of necrosis and apoptosis was determined by the TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. Cyclooxygenase 2, superoxide dismutase 2, and inducible nitric oxide synthase levels were determined by immunohistochemistry in tissue samples. RESULTS: Apoptosis and necrosis rates were higher in lipoplatin group than in cisplatin group (P=.035 and P=.010, respectively) in tumor tissue. In the spiral ganglion, apoptosis and necrosis were lower in the lipoplatin group than in cisplatin group (P=.002 and P=.002, respectively). Cyclooxygenase 2 pattern in the cochlea was positive in both control and lipoplatin group and negative in cisplatin group (P=.001). Superoxide dismutase 2 and inducible nitric oxide synthase 2 protein expressions showed no difference between groups. The auditory functions were similar to baseline values and had a better threshold value in lipoplatin group than cisplatin group. CONCLUSION: For the treatment of neuroblastoma, the use of lipoplatin seems to be beneficial in reducing side effects of cisplatin. We recommend that the mechanism of these properties of lipoplatin should be evaluated in further studies.

Comparison of Cisplatin with Lipoplatin in Terms of Ototoxicity.

OBJECTIVE: Cisplatin (CDDP) is an anti-neoplastic agent that has been used in treatments of both pediatric and adult cancers. It has many side effects, such as ototoxicity, nephrotoxicity, and neurotoxicity. Lipoplatin (LIPO) is a nanomolecule with 110 nm diameter and composed of lipids and CDDP. In this study, we aimed to compare the toxic effects of LIPO with CDDP in the cochlear cells with anti-tumoral doses determined in neuroblastoma cells. MATERIALS AND METHODS: House Ear Institute Organ Corti 1 (HEI-OC1), MYC-N amplified KELLY, and MYC-N non-amplified SH-SY5Y human neuroblastoma cells were used in this study. Firstly, anti-tumoral lethal dose 50 (LD50) of LIPO and CDDP were determined using the WST-1 assay in both neuroblastoma cells. Then anti-tumoral doses of CDDP and LIPO were applied on HEI-OC1 cells for evaluating the toxic effects. The apoptotic cell death was measured using flow cytometric analysis of annexin-V/7-amino-actinomycin (7-AAD) and cell cycle tests. RESULTS: LIPO or CDDP inhibited cell viability in a dose- and time-dependent manner in both neuroblastoma and HEI-OC1 cells. LD50 values were selected as 20 mM for CDDP and 750 mM for LIPO in neuroblastoma cells. After the 48-hour incubation, KELLY cells treated with 20 mM CDDP and 750 mM LIPO had a 53% viability; SH-SY5Y cells treated 20 mM CDDP and 750 mM LIPO had a 45% and 58% viability, respectively; and HEI-OC1 cells treated with 20 mM CDDP and 750 mM LIPO had a 65% and 82% viability, respectively. CONCLUSION: LIPO showed less toxic effects in the HEI-OC1 cells compared to CDDP at anti-tumoral doses.