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Supplementary Data from Genomic Profiling of Chondrosarcoma: Chromosomal Patterns in Central and Peripheral Tumors

Purpose: Histologic grade is currently the best predictor of clinical course in chondrosarcoma patients. Grading suffers, however, from extensive interobserver variability and new objective markers are needed. Hence, we have investigated DNA copy numbers in chondrosarcomas with the purpose of identifying markers useful for prognosis and subclassification.Experimental Design: The overall pattern of genomic imbalances was assessed in a series of 67 chondrosarcomas using array comparative genomic hybridization. Statistical analyses were applied to evaluate the significance of alterations detected in subgroups based on clinical data, morphology, grade, tumor size, and karyotypic features. Also, the global gene expression profiles were obtained in a subset of the tumors.Results: Genomic imbalances, in most tumors affecting large regions of the genome, were found in 90% of the cases. Several apparently distinctive aberrations affecting conventional central and peripheral tumors, respectively, were identified. Although rare, recurrent amplifications were found at 8q24.21-q24.22 and 11q22.1-q22.3, and homozygous deletions of loci previously implicated in chondrosarcoma development affected the CDKN2A, EXT1, and EXT2 genes. The chromosomal imbalances in two distinct groups of predominantly near-haploid and near-triploid tumors, respectively, support the notion that polyploidization of an initially hyperhaploid/hypodiploid cell population is a common mechanism of chondrosarcoma progression. Increasing patient age as well as tumor grade were associated with adverse outcome, but no copy number imbalance affected metastasis development or tumor-associated death.Conclusion: Despite similarities in the overall genomic patterns, the present findings suggest that some regions are specifically altered in conventional central and peripheral tumors, respectively.

Undifferentiated pleomorphic sarcoma of bone (UPSb) is a rare tumor often difficult to differentiate from fibrosarcoma of bone (FSb), diagnostically. We applied array comparative genomic hybridization (array CGH) to screen for genes with potential importance in the tumor and compared the results with alterations seen in FSb. Twenty-two fresh frozen tissue specimens from 20 patients (18 primary tumors and 4 local recurrences) with UPSb were studied. DNA was isolated and hybridized onto Agilent 244K CGH oligoarrays. The hybridization data were analyzed using Agilent DNA Analytics Software. The number of changes ranged from 2 to 168 (average ¼ 66). Losses were most frequently seen at 8p, 9p, 10, 13q, and 18q, and gains at 4q, 5p, 6p, 7p, 8q, 12p, 14q, 17q, 19p, 20q, 22q, and X. Homozygous deletions of CDKN2A, RB1, TP53, and ING1 were seen in 8/20, 7/20, 3/20, and 2/20 cases, respectively. Hypermethylation of both p16 INK4a and p14 ARF was found in two cases with loss at CDKN2A. Inactivation either of CDKN2A, RB1 ,o rTP53 was detected in 18/20 cases. One case showed high level gains of CDK4 and MDM2. Frequent gains were seen at MYC, PDGFRA, KIT, and KDR. Immunohistochemical positivity of KIT, PDGFRA, KDR, and PDGFRB was found in 8/14, 5/14, 4/14, and 4/14 cases, respectively. The regions most significantly discriminating between UPSb and FSb included RB1 and MYC. No homozygous deletions of RB1 were found in FSb. In conclusion, our analysis showed the disruption of G1/S checkpoint regulation to be crucial for the oncogenesis of UPSb. V C 2011 Wiley-Liss, Inc.

Very little is known about the genetics of fibrosarcoma (FS) of bone. We applied array comparative genomic hybridization (CGH) to identify genes and genomic regions with potential role in the pathogenesis of this tumor. Seventeen patients with FS of bone were included in the study. Array CGH analysis was carried out in 13 fresh frozen tissue specimens from 11 of these patients (nine primary tumors and four local recurrences). DNA was extracted and hybridizations were performed on Agilent 244K CGH oligoarrays. The data were analyzed using Agilent DNA Analytics Software. The number of changes per patient ranged from 0 to 132 (average = 43). Losses were most commonly detected at 6q, 8p, 9p, 10, 13q, and 20p. CDKN2A was homozygously deleted in 7/11 patients. Hypermethylation of both p16(INK4a) and p14(ARF) was found in 1/14 patients. An internal deletion of STARD13 was found in a region with common losses at 13q13.1. The most frequent gains were seen at 1q, 4q, 5p, 8q, 12p, 15q, 16q, 17q, 20q, 22q, and Xp. Single recurrent high level amplification was detected at 4q12, including KIT, PDGFRA, and KDR. No activating mutations were found in any of them. Immunohistochemistry revealed expression of PDGFRA and/or PDGFRB in 12/17 samples. Moreover, small regions of gains pinpointed genes of particular interest, such as IGF1R at 15q26.3 and CHD1L at 1q21.1. In conclusion, our analysis provided novel findings that can be exploited when searching for markers for diagnosis and prognosis, and targets of therapy in this tumor type.

Purpose: Histologic grade is currently the best predictor of clinical course in chondrosarcoma patients. Grading suffers, however, from extensive interobserver variability and new objective markers are needed. Hence, we have investigated DNA copy numbers in chondrosarcomas with the purpose of identifying markers useful for prognosis and subclassification. Experimental Design: The overall pattern of genomic imbalances was assessed in a series of 67 chondrosarcomas using array comparative genomic hybridization. Statistical analyses were applied to evaluate the significance of alterations detected in subgroups based on clinical data, morphology, grade, tumor size, and karyotypic features. Also, the global gene expression profiles were obtained in a subset of the tumors. Results: Genomic imbalances, in most tumors affecting large regions of the genome, were found in 90% of the cases. Several apparently distinctive aberrations affecting conventional central and peripheral tumors, respectively, were identified. Although rare, recurrent amplifications were found at 8q24.21-q24.22 and 11q22.1-q22.3, and homozygous deletions of loci previously implicated in chondrosarcoma development affected the CDKN2A, EXT1, and EXT2 genes. The chromosomal imbalances in two distinct groups of predominantly near-haploid and near-triploid tumors, respectively, support the notion that polyploidization of an initially hyperhaploid/hypodiploid cell population is a common mechanism of chondrosarcoma progression. Increasing patient age as well as tumor grade were associated with adverse outcome, but no copy number imbalance affected metastasis development or tumor-associated death. Conclusion: Despite similarities in the overall genomic patterns, the present findings suggest that some regions are specifically altered in conventional central and peripheral tumors, respectively.

Background As the treatment results of childhood ALL have improved, avoidance of late effects has become increasingly important. Identification of favorable prognostic factors helps to achieve this goal. Procedure We studied the prognostic value of TEL–AML1 fusion and a risk factor composed of age, white blood cell count (WBC), lymphomatous features, and hemoglobin level (Hb). We also compared outcome between two cohorts; cohort 1 (n = 100) diagnosed 1975–1981, and cohort 2 (n = 102) 1989–1991. Both cohorts were retrospectively divided in two groups: very-low-risk (WBC

Summary. The expression of apoptosis-related genes BCL2, BAX, BCL2L1, BCL2A1, MCL1, DAPK1 and MYC was studied by quantitative real-time polymerase chain reaction on total RNA samples from patients with acute lymphoblastic leukaemia (ALL, n = 16), acute myeloid leukaemia (AML, n = 27), chronic myeloid leukaemia (CML, n = 12), mantle cell lymphoma (MCL, n = 19) and chronic lymphoid leukaemia (CLL, n = 32). BCL2, BAX, BCL2A1, MCL1, DAPK1 and MYC were overexpressed in all patient groups. BCL2L1 was underexpressed in CLL and CML, but not in AML, ALL and MCL. MCL1 levels were significantly higher in CD13 and CD33-positive ALL, and in CD56-positive AML samples. BCL2, BCL2L1, BCL2A1 and MCL1 were overexpressed and DAPK1 was underexpressed in CLL samples with a 11q23 deletion. MYC overexpression was significantly associated with shorter overall survival in MCL (P

The knowledge about the genetics of bone tumors has considerably expanded in the past two decades, including discovery of a number of tumor-specific genetic alterations. The studies have provided novel biomarkers for bone tumor diagnostics, as well as candidate targets for therapies. This review gives a comprehensive overview about genetic alterations in both benign and malignant bone tumors, covering nearly all bone tumor entities and lacking only a few rarest ones with extremely scarce data. In addition, the most important techniques used in the diagnostics and research of bone tumors are presented.

The molecular and genetic characteristics of ameloblastoma are still poorly understood. We analyzed gene expression in fresh-frozen ameloblastomas and human fetal tooth germs, using a cDNA microarray. Thirty-four genes exhibited significant changes in expression levels in the ameloblastoma. Eleven genes were overexpressed more than three-fold, and 23 genes were underexpressed to below 0.4 of the control level. The oncogene FOS was the most overexpressed gene (from eight- to 14-fold), followed by tumor-necrosis-factor-receptor 1 ( TNFRSF1A). Genes for sonic hedgehog ( SHH), TNF-receptor-associated-factor 3 ( TRAF3), rhoGTP-ase-activating protein 4 ( ARHGAP4), deleted in colorectal carcinoma ( DCC), cadherins 12 and 13 ( CDH12 and 13), teratocarcinoma-derived growth-factor-1 ( TDGF1), and transforming growth-factor-ß1 ( TGFB1) were underexpressed in all tumors. In selected genes, a comparison between cDNA microarray and real-time RT-PCR confirmed similar relative gene expression changes. The gene expression profile identifies candidate genes that may be involved in the origination of ameloblastoma and several genes previously unidentified in relation to human tooth development.

Background Genetic aberrations provide prognostic information in childhood ALL. The proportion of patients with detectable aberrations can be increased by combining G-banding with comparative genomic hybridization (CGH). Procedure We studied 79 children with ALL by CGH and G-banding, and explored the relationship of these findings to clinical features and outcome. Results CGH revealed DNA copy number changes in 57 patients (72%), 9 of whom had normal karyotype by G-banding. Gains were more frequent than losses, and changes of whole chromosomes more frequent than partial aberrations. Two frequent partial losses were found; at 9p and 12p. The 9 patients with loss at 12p were studied for the deletion of TEL (ETV6) gene and the fusion of TEL and AML1 genes by fluorescent in situ hybridization (FISH). Eight out of the 9 children with loss at 12p harbored the TEL–AML1 translocation and all 9 had the deletion of a nontranslocated TEL allele. All 9 had precursor-B phenotype and L1 morphology, and 8/9 had WBC below 50 × 109/liter. All children were treated according to Nordic ALL protocols, had a good response to treatment based on day 15 bone marrow morphology, and 7 out of the 9 survived in continuous complete remission (median follow-up 74 months). Conclusions CGH is a valuable tool in screening for genetic aberrations in childhood ALL. DNA copy number losses detected at 12p associate with TEL–AML1 fusion as well as with favorable prognostic features. Med Pediatr Oncol 2001; 37:419–425. © 2001 Wiley-Liss, Inc.

Background Xenografts have been shown to provide a suitable source of tumor tissue for molecular analysis in the absence of primary tumor material. We utilized ES xenograft series for integrated microarray analyses to identify novel biomarkers. Method Microarray technology (array comparative genomic hybridization (aCGH) and micro RNA arrays) was used to screen and identify copy number changes and differentially expressed miRNAs of 34 and 14 passages, respectively. Incubated cells used for xenografting (Passage 0) were considered to represent the primary tumor. Four important differentially expressed miRNAs (miR-31, miR-31*, miR-145, miR-106) were selected for further validation by real time polymerase chain reaction (RT-PCR). Integrated analysis of aCGH and miRNA data was performed on 14 xenograft passages by bioinformatic methods. Results The most frequent losses and gains of DNA copy number were detected at 9p21.3, 16q and at 8, 15, 17q21.32-qter, 1q21.1-qter, respectively. The presence of these alterations was consistent in all tumor passages. aCGH profiles of xenograft passages of each series resembled their corresponding primary tumors (passage 0). MiR-21, miR-31, miR-31*, miR-106b, miR-145, miR-150*, miR-371-5p, miR-557 and miR-598 showed recurrently altered expression. These miRNAS were predicted to regulate many ES-associated genes, such as genes of the IGF1 pathway, EWSR1, FLI1 and their fusion gene (EWS-FLI1). Twenty differentially expressed miRNAs were pinpointed in regions carrying altered copy numbers. Conclusion In the present study, ES xenografts were successfully applied for integrated microarray analyses. Our findings showed expression changes of miRNAs that were predicted to regulate many ES associated genes, such as IGF1 pathway genes, FLI1, EWSR1, and the EWS-FLI1 fusion genes.

Chondrosarcoma is a malignant bone tumor that is often resistant to chemotherapy and radiotherapy. We applied high resolution oligonucleotide array comparative genomic hybridization to 46 tumor specimens from 44 patients with chondrosarcoma and identified several genes with potential importance for the development of chondrosarcoma. Several homozygous deletions were detected. The tumor suppressor genes CDKN2A and MTAP were each homozygously deleted in four of the cases, and the RB1 gene was homozygously deleted in one. Two homozygous deletions of MTAP did not affect CDKN2A. Deletions were also found to affect genes of the cadherin family, including CDH4 and CDH7, each of which had a targeted homozygous loss in one case, and CDH19, which had a targeted homozygous loss in two cases. Loss of the EXT1 and EXT2 genes was uncommon; EXT1 was homozygously deleted in none and EXT2 in two of the cases, and large heterozygous losses including EXT1 and/or EXT2 were seen in three cases. Targeted gains and amplifications affected the MYC, E2F3, CDK6, PDGFRA, KIT, and PDGFD genes in one case each. The data indicate that chondrosarcomas develop through a combination of genomic imbalances that often affect the RB1 signaling pathway. The inactivation of cadherin genes may also be critical in the pathogenesis of the tumor.

Very little is known about the genetics of fibrosarcoma (FS) of bone. We applied array comparative genomic hybridization (CGH) to identify genes and genomic regions with potential role in the pathogenesis of this tumor. Seventeen patients with FS of bone were included in the study. Array CGH analysis was carried out in 13 fresh frozen tissue specimens from 11 of these patients (nine primary tumors and four local recurrences). DNA was extracted and hybridizations were performed on Agilent 244K CGH oligoarrays. The data were analyzed using Agilent DNA Analytics Software. The number of changes per patient ranged from 0 to 132 (average = 43). Losses were most commonly detected at 6q, 8p, 9p, 10, 13q, and 20p. CDKN2A was homozygously deleted in 7/11 patients. Hypermethylation of both p16(INK4a) and p14(ARF) was found in 1/14 patients. An internal deletion of STARD13 was found in a region with common losses at 13q13.1. The most frequent gains were seen at 1q, 4q, 5p, 8q, 12p, 15q, 16q, 17q, 20q, 22q, and Xp. Single recurrent high level amplification was detected at 4q12, including KIT, PDGFRA, and KDR. No activating mutations were found in any of them. Immunohistochemistry revealed expression of PDGFRA and/or PDGFRB in 12/17 samples. Moreover, small regions of gains pinpointed genes of particular interest, such as IGF1R at 15q26.3 and CHD1L at 1q21.1. In conclusion, our analysis provided novel findings that can be exploited when searching for markers for diagnosis and prognosis, and targets of therapy in this tumor type.

As the treatment results of childhood ALL have improved, avoidance of late effects has become increasingly important. Identification of favorable prognostic factors helps to achieve this goal.We studied the prognostic value of TEL-AML1 fusion and a risk factor composed of age, white blood cell count (WBC), lymphomatous features, and hemoglobin level (Hb). We also compared outcome between two cohorts; cohort 1 (n=100) diagnosed 1975-1981, and cohort 2 (n=102) 1989-1991. Both cohorts were retrospectively divided in two groups: very-low-risk (WBC10 x 10(9)/L, age 2 to10 years, no lymphomatous features, Hb90 g/L), and non-low-risk (=the remainder). We performed fluorescent in situ hybridization (FISH) of TEL-AML1 fusion of the marrow samples obtained at diagnosis.The median follow-up is 20 years in cohort 1, and 8 years in cohort 2. In both cohorts, the very-low-risk category comprised one-fourth of the children. TEL-AML1 fusion was more frequent in the very-low-risk (35%) than in the non-low-risk group (17%) (P=0.03). The 8-year event-free survival (EFS) of children with the fusion was better than of those without, 74 vs. 54% (P=0.040). The 8-year EFS in the very-low-risk group was 76% in cohort 1, and 79% in cohort 2 (n.s.). In the non-low-risk groups, EFS was 39 vs. 64% (P=0.02), respectively.Our data support the reported association of TEL-AML1 fusion with a favorable outcome although the risk group had a greater impact. These very-long-term follow-up data also indicate that children with very-low-risk ALL (slow disease) had a favorable outcome already in the late 1970s, and may be over treated with the contemporary ALL protocols.

Translocation-associated gene fusions are well recognized in acute myeloid leukemia. Other molecular genetic changes are less well known. The novel cDNA technology has opened the avenue to large-scale gene expression analysis. Our aim was to perform cDNA microarray analysis of acute myeloid leukemia (AML).We performed cDNA microarray analysis using the Clontech hematology filter (containing 406 genes) on 15 patients to study gene expression profiling in AML. As reference, we used whole bone marrow from 5 healthy donors.Our results revealed 50 differentially expressed genes in at least 3 out of 15 patients. Twenty-two genes were upregulated (ratioor =4), whereas 28 genes were downregulated (ratioor =0.25). All but one of the 13 genes tested by real-time polymerase chain reaction (PCR) showed the same expression profiles. Among the overexpressed genes, several were those earlier associated with chromosomal translocations and gene fusions. These genes were FGFR1, MYC, NPM1, DEC, and BCL2. The expression of two upregulated genes, HOXA4 and CSF1R, was significantly higher in patients with a white blood cell count higher than 30 x 10(9)/L cells. In patients whose white blood cell count was higher than 100 x 10(9)/L cells, both CLC and GRN were significantly underexpressed, whereas HOXA4 and DAPK1 were overexpressed. FGFR1 and CAMLG were more frequently significantly overexpressed in patients with CD56 immunophenoytpe.Clinical and prognostic significance of differential gene expression should be studied with a larger series of patients by using other techniques, such as quantitative real-time PCR.

Several specific cytogenetic changes are known to be associated with childhood acute lymphoblastic leukemia (ALL), and many of them are important prognostic factors for the disease. Little is known, however, about the changes in gene expression in ALL. Recently, the development of cDNA array technology has enabled the study of expression of hundreds to thousands of genes in a single experiment. We used the cDNA array method to study the gene expression profiles of 17 children with precursor-B ALL. Normal B cells from adenoids were used as reference material. We discuss the 25 genes that were most over-expressed compared to the reference. These included four genes that are normally expressed only in the myeloid lineages of the hematopoietic cells: RNASE2, GCSFR, PRTN3 and CLC. We also detected over-expression of S100A12, expressed in nerve cells but also in myeloid cells. In addition to the myeloid-specific genes, other over-expressed genes included AML1, LCP2 and FGF6. In conclusion, our study revealed novel information about gene expression in childhood ALL. The data obtained may contribute to further studies of the pathogenesis and prognosis of childhood ALL.