Neuroblastoma is a cancer of the sympathetic nervous system that accounts for approximately 10% of all pediatric oncology deaths. Here, we report a genome-wide association study of 2,817 ...neuroblastoma cases and 7,473 controls. We identified two new associations at 6q16, the first within HACE1 (rs4336470; combined P=2.7×10(-11); odds ratio 1.26, 95% confidence interval (CI) 1.18-1.35) and the second within LIN28B (rs17065417; combined P=1.2×10(-8); odds ratio 1.38, 95% CI 1.23-1.54). Expression of LIN28B and let-7 miRNA correlated with rs17065417 genotype in neuroblastoma cell lines, and we observed significant growth inhibition upon depletion of LIN28B, specifically in neuroblastoma cells that were homozygous for the risk allele. Low HACE1 and high LIN28B expression in diagnostic primary neuroblastomas were associated with worse overall survival (P=0.008 and 0.014, respectively). Taken together, these data show that common variants in HACE1 and LIN28B influence neuroblastoma susceptibility and indicate that both genes likely have a role in disease progression.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Neuroblastoma is a childhood cancer that can be inherited, but the genetic aetiology is largely unknown. Here we show that germline mutations in the anaplastic lymphoma kinase (ALK) gene explain most ...hereditary neuroblastomas, and that activating mutations can also be somatically acquired. We first identified a significant linkage signal at chromosome bands 2p23-24 using a whole-genome scan in neuroblastoma pedigrees. Resequencing of regional candidate genes identified three separate germline missense mutations in the tyrosine kinase domain of ALK that segregated with the disease in eight separate families. Resequencing in 194 high-risk neuroblastoma samples showed somatically acquired mutations in the tyrosine kinase domain in 12.4% of samples. Nine of the ten mutations map to critical regions of the kinase domain and were predicted, with high probability, to be oncogenic drivers. Mutations resulted in constitutive phosphorylation, and targeted knockdown of ALK messenger RNA resulted in profound inhibition of growth in all cell lines harbouring mutant or amplified ALK, as well as in two out of six wild-type cell lines for ALK. Our results demonstrate that heritable mutations of ALK are the main cause of familial neuroblastoma, and that germline or acquired activation of this cell-surface kinase is a tractable therapeutic target for this lethal paediatric malignancy.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
More than 900 samples of neuroblastoma were screened for loss of chromosomal material at two loci, 1p36 and 11q23. These abnormalities were associated with high-risk features of neuroblastoma or a ...poor clinical outcome.
In samples of neuroblastoma that were screened for loss of chromosomal material at two loci, abnormalities were associated with high-risk features of neuroblastoma or a poor clinical outcome.
Neuroblastoma is a cancer of early childhood in which genomic changes in the tumor correlate with its behavior and outcome in patients.
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The algorithm devised by the Children's Oncology Group for risk assessment in cases of neuroblastoma has been successful in distinguishing patients with aggressive disease from those with a high likelihood of cure after surgery or even observation alone. The algorithm stratifies patients into three subgroups with expected low, intermediate, and high risks of death from neuroblastoma. This system involves the use of the clinical factors of age at diagnosis, tumor stage, and the results of the Shimada . . .
Neuroblastoma is a malignant neoplasm of the developing sympathetic nervous system that is notable for its phenotypic diversity. High-risk patients typically have widely disseminated disease at ...diagnosis and a poor survival probability, but low-risk patients frequently have localized tumors that are almost always cured with little or no chemotherapy. Our genome-wide association study (GWAS) has identified common variants within FLJ22536, BARD1, and LMO1 as significantly associated with neuroblastoma and more robustly associated with high-risk disease. Here we show that a GWAS focused on low-risk cases identified SNPs within DUSP12 at 1q23.3 (P = 2.07 × 10⁻⁶), DDX4 and IL31RA both at 5q11.2 (P = 2.94 × 10⁻⁶ and 6.54 × 10⁻⁷ respectively), and HSD17B12 at 11p11.2 (P = 4.20 × 10⁻⁷) as being associated with the less aggressive form of the disease. These data demonstrate the importance of robust phenotypic data in GWAS analyses and identify additional susceptibility variants for neuroblastoma.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A more complete understanding of aberrant oncogenic signaling in neuroblastoma, a malignancy of the developing sympathetic nervous system, is paramount to improving patient outcomes. Recently, we ...identified LIN28B as an oncogenic driver in high-risk neuroblastoma. Here, we identify the oncogene RAN as a LIN28B target and show regional gain of chromosome 12q24 as an additional somatic alteration resulting in increased RAN expression. We show that LIN28B influences RAN expression by promoting RAN Binding Protein 2 expression and by directly binding RAN mRNA. Further, we demonstrate a convergence of LIN28B and RAN signaling on Aurora kinase A activity. Collectively, these findings demonstrate that LIN28B-RAN-AURKA signaling drives neuroblastoma oncogenesis, suggesting that this pathway may be amenable to therapeutic targeting.
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•LIN28B and regional gain of chromosome 12q24 mediate RAN oncogene overexpression•RAN promotes cell proliferation in neuroblastoma•LIN28B promotes RAN levels by binding RAN mRNA and via RAN binding protein 2•LIN28B promotes Aurora kinase A expression in a let-7-dependent manner
Extending from prior identification of LIN28B as an oncogenic driver in high-risk neuroblastoma, Schnepp et al. show that LIN28B regulates the RAN level directly by mRNA binding and indirectly via let-7-regulated RANBP2. LIN28B and RAN signaling converge on Aurora kinase A, suggesting therapeutic potential.
Neuroblastoma is a childhood cancer that is often fatal despite intense multimodality therapy. In an effort to identify therapeutic targets for this disease, we performed a comprehensive ...loss-of-function screen of the protein kinome. Thirty kinases showed significant cellular cytotoxicity when depleted, with loss of the cell cycle checkpoint kinase 1 (CHK1/CHEK1) being the most potent. CHK1 mRNA expression was higher in MYC-Neuroblastoma-related (MYCN)-amplified (P < 0.0001) and high-risk (P = 0.03) tumors. Western blotting revealed that CHK1 was constitutively phosphorylated at the ataxia telangiectasia response kinase target site Ser345 and the autophosphorylation site Ser296 in neuroblastoma cell lines. This pattern was also seen in six of eight high-risk primary tumors but not in control nonneuroblastoma cell lines or in seven of eight low-risk primary tumors. Neuroblastoma cells were sensitive to the two CHK1 inhibitors SB21807 and TCS2312, with median IC₅₀ values of 564 nM and 548 nM, respectively. In contrast, the control lines had high micromolar IC₅₀ values, indicating a strong correlation between CHK1 phosphorylation and CHK1 inhibitor sensitivity (P = 0.0004). Furthermore, cell cycle analysis revealed that CHK1 inhibition in neuroblastoma cells caused apoptosis during S-phase, consistent with its role in replication fork progression. CHK1 inhibitor sensitivity correlated with total MYC(N) protein levels, and inducing MYCN in retinal pigmented epithelial cells resulted in CHK1 phosphorylation, which caused growth inhibition when inhibited. These data show the power of a functional RNAi screen to identify tractable therapeutical targets in neuroblastoma and support CHK1 inhibition strategies in this disease.
MicroRNAs are small noncoding RNAs that have critical roles in regulating a number of cellular functions through transcriptional
silencing. They have been implicated as oncogenes and tumor suppressor ...genes (oncomirs) in several human neoplasms. We used
an integrated genomics and functional screening strategy to identify potential oncomirs in the pediatric neoplasm neuroblastoma.
We first identified microRNAs that map within chromosomal regions that we and others have defined as frequently deleted (1p36,
3p22, and 11q23-24) or gained (17q23) in high-risk neuroblastoma. We then transiently transfected microRNA precursor mimics
or inhibitors into a panel of six neuroblastoma cell lines that we characterized for these genomic aberrations. The majority
of transfections showed no phenotypic effect, but the miR-34a (1p36) and miR-34c (11q23) mimics showed dramatic growth inhibition
in cell lines with 1p36 hemizygous deletion. In contrast, there was no growth inhibition by these mimics in cell lines without
1p36 deletions. Quantitative reverse transcription-PCR showed a perfect correlation of absent miR-34a expression in cell lines
with a 1p36 aberration and phenotypic effect after mimetic add-back. Expression of miR-34a was also decreased in primary tumors
( n = 54) with 1p36 deletion ( P = 0.009), but no mutations were discovered in resequencing of the miR-34a locus in 30 neuroblastoma cell lines. Flow cytometric
time series analyses showed that the likely mechanism of miR-34a growth inhibition is through cell cycle arrest followed by
apoptosis. BCL2 and MYCN were identified as miR-34a targets and likely mediators of the tumor suppressor phenotypic effect.
These data support miR-34a as a tumor suppressor gene in human neuroblastoma. (Mol Cancer Res 2008;6(5):735–42)
The majority of patients with neuroblastoma have tumors that initially respond to chemotherapy, but a large proportion will experience therapy-resistant relapses. The molecular basis of this ...aggressive phenotype is unknown. Whole-genome sequencing of 23 paired diagnostic and relapse neuroblastomas showed clonal evolution from the diagnostic tumor, with a median of 29 somatic mutations unique to the relapse sample. Eighteen of the 23 relapse tumors (78%) showed mutations predicted to activate the RAS-MAPK pathway. Seven of these events were detected only in the relapse tumor, whereas the others showed clonal enrichment. In neuroblastoma cell lines, we also detected a high frequency of activating mutations in the RAS-MAPK pathway (11/18; 61%), and these lesions predicted sensitivity to MEK inhibition in vitro and in vivo. Our findings provide a rationale for genetic characterization of relapse neuroblastomas and show that RAS-MAPK pathway mutations may function as a biomarker for new therapeutic approaches to refractory disease.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
We conducted a SNP-based genome-wide association study (GWAS) focused on the high-risk subset of neuroblastoma. As our previous unbiased GWAS showed strong association of common 6p22 SNP alleles with ...aggressive neuroblastoma, we restricted our analysis here to 397 high-risk cases compared to 2,043 controls. We detected new significant association of six SNPs at 2q35 within the BARD1 locus (Pallelic = 2.35 × 10−9-2.25 × 10−8). We confirmed each SNP association in a second series of 189 high-risk cases and 1,178 controls (Pallelic = 7.90 × 10−7-2.77 × 10−4). We also tested the two most significant SNPs (rs6435862, rs3768716) in two additional independent high-risk neuroblastoma case series, yielding combined allelic odds ratios of 1.68 each (P = 8.65 × 10−18 and 2.74 × 10−16, respectively). We also found significant association with known BARD1 nonsynonymous SNPs. These data show that common variation in BARD1 contributes to the etiology of the aggressive and most clinically relevant subset of human neuroblastoma.
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Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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