scholarly journals Copy Number Alterations in Hepatoblastoma: Literature Review and a Brazilian Cohort Analysis Highlight New Biological Pathways

2021 ◽  
Vol 11 ◽  
Author(s):  
Juliana Sobral Barros ◽  
Talita Ferreira Marques Aguiar ◽  
Silvia Souza Costa ◽  
Maria Prates Rivas ◽  
Monica Cypriano ◽  
...  

Hepatoblastoma (HB) is a rare embryonal tumor, although it is the most common pediatric liver cancer. The aim of this study was to provide an accurate cytogenomic profile of this type of cancer, for which information in cancer databases is lacking. We performed an extensive literature review of cytogenetic studies on HBs disclosing that the most frequent copy number alterations (CNAs) are gains of 1q, 2/2q, 8/8q, and 20; and losses at 1p and 4q. Furthermore, the CNA profile of a Brazilian cohort of 26 HBs was obtained by array-CGH; the most recurrent CNAs were the same as shown in the literature review. Importantly, HBs from female patients, high-risk stratification tumors, tumors who developed in older patients (> 3 years at diagnosis) or from patients with metastasis and/or deceased carried a higher diversity of chromosomal alterations, specifically chromosomal losses at 1p, 4, 11q and 18q. In addition, we distinguished three major CNA profiles: no detectable CNA, few CNAs and tumors with complex genomes. Tumors with simpler genomes exhibited a significant association with the epithelial fetal subtype of HBs; in contrast, the complex genome group included three cases with epithelial embryonal histology, as well as the only HB with HCC features. A significant association of complex HB genomes was observed with older patients who developed high-risk tumors, metastasis, and deceased. Moreover, two patients with HBs exhibiting complex genomes were born with congenital anomalies. Together, these findings suggest that a high load of CNAs, mainly chromosomal losses, particularly losses at 1p and 18, increases the tendency to HB aggressiveness. Additionally, we identified six hot-spot chromosome regions most frequently affected in the entire group: 1q31.3q42.3, 2q23.3q37.3, and 20p13p11.1 gains, besides a 5,3 Mb amplification at 2q24.2q24.3, and losses at 1p36.33p35.1, 4p14 and 4q21.22q25. An in-silico analysis using the genes mapped to these six regions revealed several enriched biological pathways such as ERK Signaling, MicroRNAs in Cancer, and the PI3K-Akt Signaling, in addition to the WNT Signaling pathway; further investigation is required to evaluate if disturbances of these pathways can contribute to HB tumorigenesis. The analyzed gene set was found to be associated with neoplasms, abnormalities of metabolism/homeostasis and liver morphology, as well as abnormal embryonic development and cytokine secretion. In conclusion, we have provided a comprehensive characterization of the spectrum of chromosomal alterations reported in HBs and identified specific genomic regions recurrently altered in a Brazilian HB group, pointing to new biological pathways, and relevant clinical associations.

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4091-4091
Author(s):  
Maria Sara Felice ◽  
Patricia Laura Rubio ◽  
Myriam Ruth Guitter ◽  
Jorge Gabriel Rossi ◽  
Jorge Alberto Digiorge ◽  
...  

Abstract Introduction: Survival of children with acute lymphoblastic leukemia (ALL) has improved in the last decades, achieving approximately 80% in Argentina. However, relapses remain the most frequent adverse event and the identification of patients with higher risk need to be refined. Deletions in IKZF1(IKZF1del) in addition with deletion of CDKN2A, CDKN2B,PAX5 or PAR1 region define a new subgroup of patients (IKZF1plus) with higher relapse rate and poor survival. Objectives: To analyze the characteristics of patients with IKZF1del and IKZF1plus, assessing the impact of the copy number alterations in several genes on survival of pediatric ALL treated with ALLIC strategy. Methods: This is a retrospective analysis performed in the population of patients admitted from October 2009 to May 2018. Samples of 432 patients with diagnosis of ALL were collected and analyzed by MLPA P-335 (MRC-Holland) for copy number alterations of IKZF1, EBF1, JAK2, CDKN2A, CDKN2B, PAX5, ETV6, BTG1, RB1 genes and PAR1 region. IKZF1plus cases were defined as those with IKZF1del with at least one additional deletion in: PAX5, CDKN2A, CDKN2B, PAR1 region. Patients were treated with 2 consecutive ALLIC protocols, according to studies stratification. Patient characteristics were compared with chi-square and Wilcoxon-sum-rank-test. Survival probability was analyzed with Kaplan-Meier calculation and survival results compared with Log-rank-test. Results: IKZF1 was not deleted in 345 cases, IKZF1del was detected in 87 cases and 47 of them were defined as IKZF1plus. Statistically significant higher WBC, MRD+ positivity on day 15, day 33 and week 12, more BCR-ABL+ and high-risk group cases, null response and higher relapse rate were observed in the IKZF1del group (total) when comparing with IKZF1 not del, and also when comparing IKZF1plus vs IKZF1 not del + IKZF1del only. EFS (SE) and DFS (SE) probabilities were: 73 (4)% and 75 (3)% for IKZF1 not del, 66 (9)% and 70 (9)% for IKZF1del, and 20 (10)% and 21 (10)% for IKZF1plus, respectively (p<0.00001).DFS of the standard-risk group was not influenced by the presence of only 1 case of IKZF1del detected in this risk-group of patients. However, DFS of intermediate-risk patients was 41 (11)% for IKZF1plus while 70 (7)% and 73 (4)% were achieved for IKZF1del and IKZF1 not del respectively (p=0,0083). Therefore, high-risk patients with IKZF1plus achieved DFS of 12 (19)% vs 65 (7)% and 50 (21)% for IKZF not del and IKZF1del respectively (p=0.0085). DFS of patients with IKZF1del + CDKN2Adel was 30 (10)% and CDKN2A not deleted 67 (9)% (p=0.0433). DFS of patients with IKZF1del + CDKN2Bdel was 42 (12)% and 66 (9)% for CDKN2B not del. DFS of cases with IKZF1del in addition to deletion of ETV6, BTG1, EBF1 orJAK2 did not show statistically significant differences when comparing with IKZF1del + normal copy number of these genes. In addition, DFS of cases with RB1del was 36 (13)% while cases without RB1del showed 70 (3)% (p=0.0071). Conclusions: 1- Patients with IKZF1del and IKZF1plus disclosed biological features related to poor outcome. 2- IKZF1plus was associated with a poor outcome in intermediate and high-risk groups according to ALLIC stratification. 3- The addition of CDKN2Adel to IKZF1del influence the outcome. However, CDKN2Bdel did not show the same effect. 4- Copy number alterations of ETV6, BTG1, EBF1 or JAK2 did not demonstrate prognostic impact. 5- RB1 showed negative influence in survival. 6- Identification of patients with IKZF1plus at diagnosis could be very useful for improving risk-group stratification of pediatric ALL patients. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 7-8
Author(s):  
Pablo Mozas ◽  
Cristina López ◽  
Marta Grau ◽  
Sara Valle ◽  
Giancarlo Castellano ◽  
...  

Introduction Outcomes for follicular lymphoma (FL) patients are generally good. Clinical and biological variables have been studied to identify patients at higher risk of early relapse, which markedly impacts survival. However, the genetic landscape of FL according to its clinical behavior (need of treatment and timing of relapse) is not well characterized, which was the aim of the present study. Patients and Methods We included 67 samples from 55 grade 1-3A FL patients from a single institution [55 samples at diagnosis (D), and 12 at relapse (R)]. Five groups were defined according to their clinical behavior: never required treatment after &gt;5 years (y) of follow-up [never treated (NT), n=7]; treated and did not relapse after &gt;9 y of follow-up, [non-relapsed (NR), n=19]; treated and relapsed beyond 24 months of frontline therapy [late relapse (LR), n=14]; treated and relapsed within 24 months of frontline treatment [early relapse (ER), n=11]; and primary refractory (PR, n=4). Of the 48 treated patients, 96% received R-CHOP. Patients developing histologic transformation were not included. DNA was extracted from FFPE tissue biopsies. Copy number alterations (CNA) were assessed in 50 D and 11 R samples [OncoScan CNV Assay (Thermofisher)], and single nucleotide variants (SNV) and insertions/deletions (indels) in 51 D and 10 R samples using a B-cell malignancy NGS panel examining 121 genes (SureSelectXT, Agilent Technologies). Genes and genomic regions were considered altered if they harbored SNV/indels and/or CNA. For comparisons and plotting, only the 52 D samples with both NGS and CNA data were considered. Non-parametric statistical tests were used. Results Median age was 56 y (range, 26−79), and 30 patients (55%) were female. Forty-two patients (76%) had stage III-IV disease, without significant differences among groups. Thirteen patients (25%) had a high-risk FLIPI score, a percentage that was higher in the LR and PR groups (50 and 67%, respectively, P=0.02). With a median follow-up of 12.9 y, 10-y overall survival estimates were 71, 100, 74, 82, and 0% for NT, NR, LR, ER, and PR patients, respectively. We detected CNA in all samples, with a median number of 7 (range, 1−27) for D samples, and of 6 (2−19) for R samples. We also identified SNV/indels in all samples, with a median number of 10 (1−23) for D samples, and of 9 (3−18) for R samples. The most commonly altered genes at diagnosis were KMT2D (82%), CREBBP (73%), SPEN (38%), TNFRSF14 (38%), ARID1A (33%), and BCL2 (33%) (Figure). There were no significant differences in the number of altered genes/regions among the five groups. Genes or regions with significantly different alteration frequency among groups were: CARD11 (57, 12, 0, 9, and 0% for NT, NR, LR, ER, and PR, respectively, P=0.014), CD70 (12% for NR, 50% for PR, and 0 for the remaining groups P=0.026), HIST1H1B (29% for NT, and 0% for the remaining groups, P=0.020), HVCN1 (43, 6, 0, 18, and 0% for NT, NR, LR, ER, and PR, respectively, P=0.048), KLHL6 (12% for NR, 75% for PR, and 0 for the remaining groups, P=0.002), PRKCB (0, 6, 0, 18, 50%, P=0.037), and 13q14.2-q14.3 loss (DLEU1/DLEU2) (24% for NR, 50% for PR, and 0 for the remaining groups, P=0.015). Two genes had a significantly lower alteration rate comparing the cases with a favorable (NT, NR, LR) and more aggressive (ER, PR) clinical behavior: CIITA (22 vs. 53%, P=0.043), and PRKCB (3 vs. 27%, P=0.044). Of the 51 patients for which the m7-FLIPI was calculated, six (12%) had a high-risk score. Of note, none of the high-risk patients belonged to the NT or NR groups. No significant differences were found in the number of altered genes/regions between D and R, or in the alteration frequency of each gene/region. We identified the presence of an ancestral common precursor cell with a divergent evolution in all paired cases. The median percentage of shared alterations between D and R was 50% (range 28−63%). Conclusions In this comprehensive genetic analysis of 55 FL patients, categorized into five groups according to their clinical behavior, alterations in the chromatin modifying genes KMT2D and CREBBP were the most frequent, and CIITA and PRKCB were more frequently altered in cases with a shorter duration of response. These data warrant further study of the mechanisms underlying these mutations, mutual exclusivity/co-occurrence, and relationships with B-cell biology and the tumor microenvironment. Disclosures Nadeu: Janssen: Honoraria. Giné:Gilead: Research Funding; Janssen: Research Funding; Roche: Research Funding. Armando:Janssen: Research Funding; Roche: Consultancy, Research Funding; Gilead: Consultancy, Research Funding; Celgene: Consultancy, Research Funding.


2009 ◽  
Vol 30 (12) ◽  
pp. 1693-1702 ◽  
Author(s):  
Karin Leunen ◽  
Olivier Gevaert ◽  
Anneleen Daemen ◽  
Vanessa Vanspauwen ◽  
Geneviève Michils ◽  
...  

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 704-704 ◽  
Author(s):  
Charles G. Mullighan ◽  
Ryan Morin ◽  
Jinghui Zhang ◽  
Martin Hirst ◽  
Yongjun Zhao ◽  
...  

Abstract Abstract 704 Relapsed ALL is a leading cause of childhood cancer death, and the biologic factors responsible for relapse are poorly understood, particularly in cases lacking sentinel chromosomal alterations. Recent studies from the Children's Oncology Group high risk ALL TARGET (Therapeutically Applicable Research to Generate Effective Targets) project that used genome-wide profiling of DNA copy number alterations and candidate gene resequencing have identified novel biomarkers of relapse (IKZF1 alteration) and therapeutic targets (JAK mutation). As a complementary approach to identify novel genomic alterations, we used second generation sequencing technology to sequence the tumor transcriptome of three cases from the COG P9906 high risk (HR) B-precursor ALL trial. The selected cases had previously been profiled by high resolution SNP and gene expression arrays and candidate gene resequencing, and lacked known sentinel chromosomal rearrangements. Each case bore features previously associated with poor treatment outcome: a gene expression profile (GEP) similar to that of BCR-ABL1 positive ALL (all cases), deletion or mutation of IZKF1 (two cases), and JAK mutation (JAK2 R867Q, one case). cDNA libraries were generated from poly-A enriched RNA and 36-50 base paired-end sequencing performed using the Illumina Genome Analyzer. Sequence alignment, variant detection and fusion transcript identification were performed using custom scripts and multiple published reference alignment and de-novo assembly algorithms. A total of 115-127 million total and 93-97 million mapped, unique reads were obtained per case. The average depth of coverage of Refseq exons ranged from 25- to 39-fold. A minimum of 5 putative fusion transcripts were identified per case, some of which were known from prior transcriptome sequencing to be recurring false positives. However, a novel transcript with an in-frame fusion of exon 9 of the striatin gene STRN3 to exon 18 of JAK2 (STRN3-JAK2) was identified in one case, and confirmed by RT-PCR and direct Sanger sequencing. Fusion of NUP214 to ABL1 was identified in a second case and also confirmed by direct sequencing. The NUP214-ABL1 rearrangement has previously only been identified in T-lineage ALL. In this case, the translocation was accompanied by amplification of the NUP214-ABL1 region at 9q. RT-PCR screening of an additional 60 high-risk ALL cases with GEP data suggestive of kinase alteration identified an additional two cases with NUP214-ABL1 fusion, each of which was accompanied by NUP214-ABL1 amplification. These two novel fusion transcripts are predicted to result in aberrant kinase signaling, and are candidates for novel therapeutic intervention. Both occurred in ALLs with a BCR-ABL1-like GEP that lacked known JAK mutations, suggesting that additional novel activating kinase mutations can be discovered via detailed sequence analysis of the 50% of BCR-ABL1-like ALLs that do not have JAK mutations. Aberrant splice variants and truncated isoforms arising from DNA copy number alterations, including internal deletions of PAX5 and truncating deletions of BTG1 were also identified using the transcriptome sequencing data. In addition, these data identified over 400 candidate non-synonymous single nucleotide and insertion/deletion variations in each patient. Known mutations involving PAX5, IKZF1 and JAK2 were robustly identified. Whole genome sequencing of matched normal DNA is underway to remove germline variation from the list of putative variants, and transcriptomic sequencing of additional cases of HR childhood ALL are being performed. Together, these data indicate that transcriptomic sequencing is a powerful method to identify novel genetic alterations in ALL, and may be used to identify novel targets for therapeutic intervention. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 250-250 ◽  
Author(s):  
Yiming Zhou ◽  
Bart Barlogie ◽  
Damir Herman ◽  
Owen Stephens ◽  
Erming Tian ◽  
...  

Abstract Multiple myeloma (MM) is characterized by a profound genomic instability and a highly variable clinical course. To comprehensively analyze the effects of copy number alterations on gene activity and prognosis, we applied novel bioinformatics and computational approaches to integrate high-resolution aCGH data (Agilent 244K array) and gene expression profiling data (Affymetrix U133Plus2.0 array) from CD138-selected plasma cells from 92 newly diagnosed MM treated with high-dose therapy and stem cell transplantation. We identified what we have termed the “atom region” (AR). ARs are found throughout the genome and define recurrent breakpoint boundaries of sub-chromosomal loss or gain. Genes coding for miRNAs were significantly enriched in regions of the genome defined by ARs. Although many AR-related breakpoints lie in intergenic regions, and thus capture whole genes, a substantial number were identified within genes, making these genes strong candidate disease genes. We found that gain of 1q and loss of 1p represent the most significant copy number alterations linked to early disease-related death. Importantly, 1q gains and 1p loss were significantly linked to a recently described 70-gene expression model of high-risk disease predominated by increased expression of genes mapping to 1q and reduced expression of genes mapping to 1p (1). Gain of 1q and loss of 1p were also highly correlated with a gene-expression-based proliferation index widely used across many tumor types. We provide evidence that gain of 8q24 was also highly correlated with the 70-gene high-risk score, but not the proliferation index. 8q24 gains and survival were linked to elevated expression of EIF2C2/AGO2, a master regulator of microRNA expression and maturation and an overexpressed gene previously identified in our 70-gene high-risk model (1). Interestingly, although the expression of MYC, which also maps to 8q24, was related to copy number changes, its expression was not related to survival. Given the importance of AGO2 in B-cell development (2), and miRNAs in cancer, detailed functional studies of the potential role of AGO2 in MM are underway.


Leukemia ◽  
2021 ◽  
Author(s):  
Anthony V. Moorman ◽  
Emilio Barretta ◽  
Ellie R. Butler ◽  
Eleanor J. Ward ◽  
Katie Twentyman ◽  
...  

AbstractChromosomal abnormalities are established prognostic markers in adult ALL. We assessed the prognostic impact of established chromosomal abnormalities and key copy number alterations (CNA) among 652 patients with B-cell precursor ALL treated on a modern MRD driven protocol. Patients with KMT2A-AFF1, complex karyotype (CK) and low hypodiploidy/near-triploidy (HoTr) had high relapse rates 50%, 60% & 53% and correspondingly poor survival. Patients with BCR-ABL1 had an outcome similar to other patients. JAK-STAT abnormalities (CRLF2, JAK2) occurred in 6% patients and were associated with a high relapse rate (56%). Patients with ABL-class fusions were rare (1%). A small group of patients with ZNF384 fusions (n = 12) had very good survival. CNA affecting IKZF1, CDKN2A/B, PAX5, BTG1, ETV6, EBF1, RB1 and PAR1 were assessed in 436 patients. None of the individual deletions or profiles were associated with survival, either in the cohort overall or within key subgroups. Collectively these data indicate that primary genetic abnormalities are stronger prognostic markers than secondary deletions. We propose a revised UKALL genetic risk classification based on key established chromosomal abnormalities: (1) very high risk: CK, HoTr or JAK-STAT abnormalities; (2) high risk: KMT2A fusions; (3) Tyrosine kinase activating: BCR-ABL1 and ABL-class fusions; (4) standard risk: all other patients.


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