Research IndicatorsGraph generated 28 February 2015 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 27 February, 2015 using data from PubMed, MeSH and CancerIndex
Specific Cancers (2)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
Search the Epigenomics database and view relevant gene tracks of samples.
Latest Publications: AIM1 (cancer-related)
Maldonado L, Brait M, Loyo M, et al.GSTP1 promoter methylation is associated with recurrence in early stage prostate cancer.
J Urol. 2014; 192(5):1542-8 [PubMed
] Related Publications
PURPOSE: Recurrent prostate cancer remains a major problem. Staging, grading and prostate specific antigen level at surgery are helpful but still imperfect predictors of recurrence. For this reason there is an imperative need for additional biomarkers that add to the prediction of currently used prognostic factors.
MATERIALS AND METHODS: We evaluated the extent of promoter methylation of genes previously reported as aberrantly methylated in prostate cancer (AIM1, APC, CCND2, GPX3, GSTP1, MCAM, RARβ2, SSBP2 and TIMP3) by quantitative fluorogenic methylation-specific polymerase chain reaction. We used cancer tissue from a nested case-control study of 452 patients surgically treated for prostate cancer. Recurrence cases and controls were compared and the association between methylation extent and recurrence risk was estimated by logistic regression adjusting for patient age at prostatectomy, prostatectomy year, stage, grade, surgical margins and preprostatectomy prostate specific antigen. All statistical tests were 2-sided with p ≤0.05 considered statistically significant.
RESULTS: The extent of GSTP1 methylation was higher in patients with recurrence than in controls (p = 0.01), especially patients with early disease, ie organ confined or limited extraprostatic extension (p = 0.001). After multivariate adjustment GSTP1 promoter methylation at or above the median was associated with an increased risk of recurrence, including in men with early disease (each p = 0.05).
CONCLUSIONS: Greater GSTP1 promoter methylation in cancer tissue was independently associated with the risk of recurrence in patients with early prostate cancer. This suggests that GSTP1 promoter methylation may be a potential tissue based recurrence marker.
PURPOSE: To elucidate the role of biological and clinical impact of aberrant promoter hypermethylation (PH) in ovarian cancer (OC).
EXPERIMENTAL DESIGN: PH of PGP9.5, HIC1, AIM1, APC, PAK3, MGMT, KIF1A, CCNA1, ESR1, SSBP2, GSTP1, FKBP4 and VGF were assessed by quantitative methylation specific PCR (QMSP) in a training set. We selected two genes (VGF and PGP9.5) for further QMSP analysis in a larger independent validation (IV) set with available clinical data. Biologic relevance of VGF gene was also evaluated.
RESULTS: PH frequency for PGP9.5 and VGF were 85% (316/372) and 43% (158/366) respectively in the IV set of samples while no PH was observed in controls. In 372 OC cases with available follow up, PGP9.5 and VGF PH were correlated with better patient survival [Hazard Ratios (HR) for overall survival (OS) were 0.59 (95% Confidence Intervals (CI) = 0.42-0.84, p = 0.004), and 0.73 (95%CI = 0.55-0.97, p = 0.028) respectively, and for disease specific survival (DSS) were 0.57 (95%CI 0.39-0.82, p = 0.003) and 0.72 (95%CI 0.54-0.96, p = 0.027). In multivariate analysis, VGF PH remained an independent prognostic factor for OS (HR 0.61, 95%CI 0.43-0.86, p<0.005) and DSS (HR 0.58, 95%CI 0.41-0.83, p<0.003). Furthermore, PGP9.5 PH was significantly correlated with lower grade, early stage tumors, and with absence of residual disease. Forced expression of VGF in OC cell lines inhibited cell growth.
CONCLUSIONS: Our results indicate that VGF and PGP9.5 PH are potential biomarkers for ovarian carcinoma. Confirmatory cohorts with longitudinal follow-up are required in future studies to define the clinical impact of VGF and PGP9.5 PH before clinical application.
Huang Y, de Leval L, Gaulard PMolecular underpinning of extranodal NK/T-cell lymphoma.
Best Pract Res Clin Haematol. 2013; 26(1):57-74 [PubMed
] Related Publications
Peripheral NK/T-cell lymphoma (PTCL) is a heterogeneous group of uncommon hematologic malignancies with aggressive clinical course and unfavorable prognosis. Extranodal NK/T-cell lymphoma, nasal type (NKTCL) is the most common extranodal entity worldwide, with heterogeneous geographic distribution, and it is characterized by its association with EBV, a nasal or less often extranasal presentation and aggressive behavior. Recent works using array-based technologies have provided novel insights into the pathogenesis and discovered new biomarkers with diagnostic and therapeutic implications in NKTCL. Gene expression profiling identified that most of the NKTCL are derived from activated natural killer cells with distinctively high expression of granzyme H compared to other PTCLs, which might serve as a new diagnostic biomarker. Frequent deletions and promoter methylations in PRDM1, ATG5, AIM1, FOXO3, HACE1 mapping to 6q21-q25, suggest their roles as potential tumor suppressors. The deregulation of oncogenic pathways (PDGF, JAK-STAT, AKT) provides a rationale for developing targeted therapies in the future.
Prostate cancer is a heterogeneous group of diseases and there is a need for more efficient and targeted methods of treatment. In this study, the potential of gene expression data and RNA interference technique were combined to advance future personalized prostate cancer therapeutics. To distinguish the most promising in vivo prevalidated prostate cancer drug targets, a bioinformatic analysis was carried out using genome-wide gene expression data from 9873 human tissue samples. In total, 295 genes were selected for further functional studies in cultured prostate cancer cells due to their high mRNA expression in prostate, prostate cancer or in metastatic prostate cancer samples. Second, RNAi based cell viability assay was performed in VCaP and LNCaP prostate cancer cells. Based on the siRNA results, gene expression patterns in human tissues and novelty, endoplasmic reticulum function associated targets AIM1, ERGIC1 and TMED3, as well as mitosis regulating TPX2 were selected for further validation. AIM1, ERGIC1, and TPX2 were shown to be highly expressed especially in prostate cancer tissues, and high mRNA expression of ERGIC1 and TMED3 associated with AR and ERG oncogene expression. ERGIC1 silencing specifically regulated the proliferation of ERG oncogene positive prostate cancer cells and inhibited ERG mRNA expression in these cells, indicating that it is a potent drug target in ERG positive subgroup of prostate cancers. TPX2 expression associated with PSA failure and TPX2 silencing reduced PSA expression, indicating that TPX2 regulates androgen receptor mediated signaling. In conclusion, the combinatorial usage of microarray and RNAi techniques yielded in a large number of potential novel biomarkers and therapeutic targets, for future development of targeted and personalized approaches for prostate cancer management.
Our aim was to comprehensively analyze promoter hypermethylation of a panel of novel and known methylation markers for thyroid neoplasms and to establish their relationship with BRAF mutation and clinicopathologic parameters of thyroid cancer. A cohort of thyroid tumors, consisting of 44 cancers and 44 benign thyroid lesions, as well as 15 samples of adjacent normal thyroid tissue, was evaluated for BRAF mutation and promoter hypermethylation. Genes for quantitative methylation specific PCR (QMSP) were selected by a candidate gene approach. Twenty-two genes were tested: TSHR, RASSF1A, RARβ2, DAPK, hMLH1, ATM, S100, p16, CTNNB1, GSTP1, CALCA, TIMP3, TGFßR2, THBS1, MINT1, CTNNB1, MT1G, PAK3, NISCH, DCC, AIM1 and KIF1A. The PCR-based "mutector assay" was used to detect BRAF mutation. All p values reported are two sided. Considerable overlap was seen in the methylation markers among the different tissue groups. Significantly higher methylation frequency and level were observed for KIF1A and RARß2 in cancer samples compared with benign tumors. A negative correlation between BRAF mutation and RASSF1A methylation, and a positive correlation with RARß2 methylation were observed in accordance with previous results. In addition, positive correlation with TIMP3 and a marginal correlation with DCC methylation were observed. The present study constitutes a comprehensive promoter methylation profile of thyroid neoplasia and shows that results must be analyzed in a tissue-specific manner to identify clinically useful methylation markers. Integration of genetic and epigenetic changes in thyroid cancer will help identify relevant biologic pathways that drive its development.
The pathogenesis of hepatosplenic T-cell lymphoma (HSTL), a rare entity mostly derived from γδ T cells and usually with a fatal outcome, remains largely unknown. In this study, HSTL samples (7γδ and 2αβ) and the DERL2 HSTL cell line were subjected to combined gene-expression profiling and array-based comparative genomic hybridization. Compared with other T-cell lymphomas, HSTL had a distinct molecular signature irrespective of TCR cell lineage. Compared with peripheral T-cell lymphoma, not otherwise specified and normal γδ T cells, HSTL overexpressed genes encoding NK-cell-associated molecules, oncogenes (FOS and VAV3), the sphingosine-1-phosphatase receptor 5 involved in cell trafficking, and the tyrosine kinase SYK, whereas the tumor-suppressor gene AIM1 (absent in melanoma 1) was among the most down-expressed. We found highly methylated CpG islands of AIM1 in DERL2 cells, and decitabine treatment induced a significant increase in AIM1 transcripts. Syk was present in HSTL cells and DERL2 cells contained phosphorylated Syk and were sensitive to a Syk inhibitor in vitro. Genomic profiles confirmed recurrent isochromosome 7q (n = 6/9) without alterations at the SYK and AIM1 loci. Our results identify a distinct molecular signature for HSTL and highlight oncogenic pathways that offer rationale for exploring new therapeutic options such as Syk inhibitors and demethylating agents.
Aberrations in the methylation status of noncoding genomic repeat DNA sequences and specific gene promoter region are important epigenetic events in melanoma progression. Promoter methylation status in long interspersed nucleotide element-1 (LINE-1) and absent in melanoma-1 (AIM1; 6q21) associated with melanoma progression and disease outcome was assessed. LINE-1 and AIM1 methylation status was assessed in paraffin-embedded archival tissue (PEAT; n = 133) and in melanoma patients' serum (n = 56). LINE-1 U-Index (hypomethylation) and AIM1 were analyzed in microdissected melanoma PEAT sections. The LINE-1 U-Index of melanoma (n = 100) was significantly higher than that of normal skin (n = 14) and nevi (n = 12; P = 0.0004). LINE-1 U-Index level was elevated with increasing American Joint Committee on Cancer (AJCC) stage (P<0.0001). AIM1 promoter hypermethylation was found in higher frequency (P = 0.005) in metastatic melanoma (65%) than in primary melanomas (38%). When analyzed, high LINE-1 U-Index and/or AIM1 methylation in melanomas were associated with disease-free survival (DFS) and overall survival (OS) in stage I/II patients (P = 0.017 and 0.027, respectively). In multivariate analysis, melanoma AIM1 methylation status was a significant prognostic factor of OS (P = 0.032). Furthermore, serum unmethylated LINE-1 was at higher levels in both stage III (n = 20) and stage IV (n = 36) patients compared with healthy donors (n = 14; P = 0.022). Circulating methylated AIM1 was detected in patients' serum and was predictive of OS in stage IV patients (P = 0.009). LINE-1 hypomethylation and AIM1 hypermethylation have prognostic utility in both melanoma patients' tumors and serum.
Castle JC, Kreiter S, Diekmann J, et al.Exploiting the mutanome for tumor vaccination.
Cancer Res. 2012; 72(5):1081-91 [PubMed
] Related Publications
Multiple genetic events and subsequent clonal evolution drive carcinogenesis, making disease elimination with single-targeted drugs difficult. The multiplicity of gene mutations derived from clonal heterogeneity therefore represents an ideal setting for multiepitope tumor vaccination. Here, we used next generation sequencing exome resequencing to identify 962 nonsynonymous somatic point mutations in B16F10 murine melanoma cells, with 563 of those mutations in expressed genes. Potential driver mutations occurred in classical tumor suppressor genes and genes involved in proto-oncogenic signaling pathways that control cell proliferation, adhesion, migration, and apoptosis. Aim1 and Trrap mutations known to be altered in human melanoma were included among those found. The immunogenicity and specificity of 50 validated mutations was determined by immunizing mice with long peptides encoding the mutated epitopes. One-third of these peptides were found to be immunogenic, with 60% in this group eliciting immune responses directed preferentially against the mutated sequence as compared with the wild-type sequence. In tumor transplant models, peptide immunization conferred in vivo tumor control in protective and therapeutic settings, thereby qualifying mutated epitopes that include single amino acid substitutions as effective vaccines. Together, our findings provide a comprehensive picture of the mutanome of B16F10 melanoma which is used widely in immunotherapy studies. In addition, they offer insight into the extent of the immunogenicity of nonsynonymous base substitution mutations. Lastly, they argue that the use of deep sequencing to systematically analyze immunogenicity mutations may pave the way for individualized immunotherapy of cancer patients.
PURPOSE: To evaluate the prognostic significance of six epigenetic biomarkers (AIM1, CDH1, KIF1A, MT1G, PAK3, and RBM6 promoter hypermethlation) in a homogeneous group of prostate cancer patients, following radical prostatectomy (RP).
PATIENTS AND METHODS: Biomarker analyses were performed retrospectively on tumors from 95 prostate cancer patients all with a Gleason score of 3 + 4 = 7 and a minimum follow-up period of 8 years. Using Quantitative Methylation Specific PCR (QMSP), we analyzed the promoter region of six genes in primary prostate tumor tissues. Time to any progression was the primary endpoint and development of metastatic disease and/or death from prostate cancer was a secondary endpoint. The association of clinicopathological and biomolecular risk factors to recurrence was performed using the Log-rank test and Cox proportional hazards model for multivariate analysis. To identify independent prognostic factors, a stepwise selection method was used.
RESULTS: At a median follow-up time of 10 years, 48 patients (50.5%) had evidence of recurrence: Biochemical/PSA relapse, metastases, or death from prostate cancer. In the final multivariate analysis for time to progression, the significant factors were: Older age, HR = 0.95 (95% CI: 0.91, 1.0) (P = 0.03), positive lymph nodes HR = 2.11 (95% CI: 1.05, 4.26) (P = 0.04), and decreased hypermethylation of AIM1 HR = 0.45 (95% CI: 0.2, 1.0) (P = 0.05).
CONCLUSIONS: Methylation status of AIM1 in the prostate cancer specimen may predict for time to recurrence in Gleason 3 + 4 = 7 patients undergoing prostatectomy. These results should be validated in a larger and unselected cohort.
Karube K, Nakagawa M, Tsuzuki S, et al.Identification of FOXO3 and PRDM1 as tumor-suppressor gene candidates in NK-cell neoplasms by genomic and functional analyses.
Blood. 2011; 118(12):3195-204 [PubMed
] Related Publications
Oligo-array comparative genomic hybridization (CGH) and gene-expression profiling of natural killer (NK)-cell neoplasms were used in an effort to delineate the molecular pathogenesis involved. Oligo-array CGH identified two 6q21 regions that were most frequently deleted (14 of 39 or 36%). One of these regions included POPDC3, PREP, PRDM1, ATG5, and AIM1, whereas the other included LACE1 and FOXO3. All genes located in these regions, except for POPDC3 and AIM1, were down-regulated in neoplastic samples, as determined by gene-expression analysis, and were therefore considered to be candidate tumor-suppressor genes. A20 and HACE1, the well-known tumor-suppressor genes located on 6q21-23, were included as candidate genes because they also demonstrated frequent genomic deletions and down-regulated expression. The Tet-Off NK cell line NKL was subsequently established for functional analyses. Seven candidate genes were transduced into Tet-Off NKL and forced re-expression was induced. Re-expression of FOXO3 and PRDM1 suppressed NKL proliferation, but this was not the case after re-expression of the other genes. This effect was confirmed using another NK cell line, SNK10. Furthermore, genomic analyses detected nonsense mutations of PRDM1 that led to functional inactivation in one cell line and one clinical sample. PRDM1 and FOXO3 are considered to play an important role in the pathogenesis of NK-cell neoplasms.
PURPOSE: We investigated the feasibility of detecting aberrant DNA methylation of some novel and known genes in the serum of lung cancer patients.
EXPERIMENTAL DESIGN: To determine the analytic sensitivity, we examined the tumor and the matched serum DNA for aberrant methylation of 15 gene promoters from 10 patients with primary lung tumors by using quantitative methylation-specific PCR. We then tested this 15-gene set to identify the more useful DNA methylation changes in the serum of a limited number of lung cancer patients and controls. In an independent set, we tested the six most promising genes (APC, CDH1, MGMT, DCC, RASSF1A, and AIM1) for further elucidation of the diagnostic application of this panel of markers.
RESULTS: Promoter hypermethylation of at least one of the genes studied was detected in all 10 lung primary tumors. In majority of cases, aberrant methylation in serum DNA was accompanied by methylation in the matched tumor samples. In the independent set, using a single gene that had 100% specificity (DCC), 35.5% (95% CI: 25-47) of the 76 lung cancer patients were correctly identified. For patients without methylated DCC, addition of a logistic regression score that was based on the five remaining genes improved sensitivity from 35.5% to 75% (95% CI: 64-84) but decreased the specificity from 100% to 73% (95% CI: 54-88).
CONCLUSION: This approach needs to be evaluated in a larger test set to determine the role of this gene set in early detection and surveillance of lung cancer.
Nasopharyngeal carcinoma (NPC) is a rare malignancy with unique genetic, viral and environmental characteristic that distinguishes it from other head and neck carcinomas. The clinical management of NPC remains challenging largely due to the lack of early detection strategies for this tumor. In our study, we have sought to identify novel genes involved in the pathogenesis of NPC that might provide insight into this tumor's biology and could potentially be used as biomarkers. To identify these genes, we studied the epigenetics of NPC by characterizing a panel of methylation markers. Eighteen genes were evaluated by quantitative methylation-specific polymerase chain reaction (PCR) in cell lines as well as in tissue samples including 50 NPC tumors and 28 benign nasopharyngeal biopsies. Significance was evaluated using Fisher's exact test and quantitative values were optimized using cut off values derived from receiver-operator characteristic curves. The methylation status of AIM1, APC, CALCA, deleted in colorectal carcinomas (DCC), DLEC, deleted in liver cancer 1 (DLC1), estrogen receptor alpha (ESR), FHIT, KIF1A and PGP9.5 was significantly associated with NPC compared to controls. The sensitivity of the individual genes ranged from 26 to 66% and the specificity was above 92% for all genes except FHIT. The combination of PGP9.5, KIF1A and DLEC had a sensitivity of 84% and a specificity of 92%. Ectopic expression of DCC and DLC1 lead to decrease in colony formation and invasion properties. Our results indicate that methylation of novel biomarkers in NPC could be used to enhance early detection approaches. Additionally, our functional studies reveal previously unknown tumor suppressor roles in NPC.
de Carvalho F, Colleoni GW, Almeida MS, et al.TGFbetaR2 aberrant methylation is a potential prognostic marker and therapeutic target in multiple myeloma.
Int J Cancer. 2009; 125(8):1985-91 [PubMed
] Related Publications
Multiple myeloma (MM) is an incurable hematological malignancy. Different studies demonstrated the occurrence of genetic and epigenetic alterations in MM. The aberrant methylation is one of the most frequent epigenetic alterations in human genome. This study evaluated the aberrant methylation status of 20 genes in 51 MM samples by quantitative methylation-specific PCR (QMSP) and compared the methylation profile with clinicopathological characteristics of the patients. The QMSP analyses showed that PTGS2 (100.0%), SFN (100.0%), CDKN2B (90.2%), CDH1 (88.2%), ESR1 (72.5%), HIC1 (70.5%), CCND2 (62.7%), DCC (45.1%) and TGFbetaR2 (39.2%) are frequently hypermethylated in MM while aberrant methylation of RARbeta (16.6%), MGMT (12.5%), AIM1 (12.5%), CDKN2A (8.3%), SOCS1 (8.3%), CCNA1 (8.3%) and THBS1 (4.1%) are rare events. There was no methylation of GSTP1, MINT31, p14ARF and RB1 in the samples tested. Hypermethylation of ESR1 was correlated positively with isotype IgA, while aberrant methylation of THBS1 correlated negatively with isotype IgG. Furthermore, hypermethylation of DCC and TGFbetaR2 were correlated with poor survival. The multivariate analysis showed ISS and TGFbetaR2 hypermethylation strongly correlated with poor outcome. This study represents the first quantitative evaluation of promoter methylation in MM and our data provide evidence that TGFbetaR2 hypermethylation, besides ISS, may be useful as prognostic indicator in this disease.
Iqbal J, Kucuk C, Deleeuw RJ, et al.Genomic analyses reveal global functional alterations that promote tumor growth and novel tumor suppressor genes in natural killer-cell malignancies.
Leukemia. 2009; 23(6):1139-51 [PubMed
] Related Publications
Natural killer (NK)-cell malignancies are among the most aggressive lymphoid neoplasms with very poor prognosis. We performed array comparative genomic hybridization analysis on a number of NK cell lines and primary tumors to gain better understanding of the pathogenesis and tumor biology of these malignancies. We also obtained transcriptional profiles of genes residing in these regions and compared them with normal and activated NK cells. Only 30-50% of the genes residing in the gained or deleted regions showed corresponding increased or decreased expression. However, many of the upregulated genes in regions of gain are functionally important for the proliferation and growth of the neoplastic population. Genes downregulated in regions of loss included many transcription factors or repressors, tumor suppressors or negative regulators of the cell cycle. The minimal common region of deletion in 6q21 included three known genes (PRDM1, ATG5 and AIM1) showing generally low expression. Mutations resulting in truncated PRDM1 and changes in conserved amino-acid sequences of AIM1 were detected. Highly methylated CpG islands 5' of PRDM1 and AIM1 correlated with low expression of the transcripts. Reversal of methylation by Decitabine induced expression of PRDM1 and cell death. In conclusion, we have shown a general tumor-promoting effect of genetic alterations and have identified PRDM1 as the most likely target gene in del6q21. ATG5, an essential gene for autophagy and AIM1, a gene implicated in melanoma, may also participate in the functional abnormalities.
PURPOSE: The aims of our study were to elucidate the role of methylation of a large panel of genes during multistage pathogenesis of bladder cancer and to correlate our findings with patient age and other clinicopathologic features.
EXPERIMENTAL DESIGN: We studied the methylation status of 21 genes by quantitative methylation-specific PCR in an evaluation set of 25 tumor and 5 normal samples. Based on methylation frequency in tumors and normals in gene evaluation set, we selected 7 candidate genes and tested an independent set of 93 tumors and 26 normals. The presence or absence of methylation was evaluated for an association with cancer using cross-tabulations and chi(2) or Fisher's exact tests as appropriate. All statistical tests were two-sided.
RESULTS: Most primary tumors (89 of 93, 96%) had methylation of one or more genes of independent set; 53 (57%) CCNA1, 29 (31%) MINT1, 36 (39%) CRBP, 53 (57%) CCND2, 66 (71%) PGP9.5, 60 (65%) CALCA, and 78 (84%) AIM1. Normal uroepithelium samples from 26 controls revealed no methylation of the CCNA1 and MINT1 genes, whereas methylation of CRBP, CCND2, PGP9.5, and CALCA was detected at low levels. All the 7 genes in independent set were tightly correlated with each other and 3 of these genes showed increased methylation frequencies in bladder cancer with increasing age. PGP9.5 and AIM1 methylation correlated with primary tumor invasion.
CONCLUSION: Our results indicate that the methylation profile of novel genes in bladder cancers correlates with clinicopathologic features of poor prognosis and is an age-related phenomenon.
Lehmann S, Ogawa S, Raynaud SD, et al.Molecular allelokaryotyping of early-stage, untreated chronic lymphocytic leukemia.
Cancer. 2008; 112(6):1296-305 [PubMed
] Related Publications
BACKGROUND: To the authors' knowledge, genetic abnormalities in early-stage chronic lymphocytic leukemia (CLL) have not been examined fully. Single nucleotide polymorphism (SNP) genomic array (SNP-chip) is a new tool that can detect copy number changes and uniparental disomy (UPD) over the entire genome with very high resolution.
METHODS: The authors performed SNP-chip analysis on 56 samples from patients with early-stage, untreated CLL. To validate the SNP-chip data, fluorescence in situ hybridization (FISH) analysis was performed at selected sites. Expression levels of ZAP-70 and the mutational status of immunoglobulin heavy-chain gene also were examined.
RESULTS: SNP-chip analysis easily detected nearly all changes that were identified by FISH, including trisomy 12, deletion of TP53 (17p13), deletion of ATM (11q22), and deletion of 13q14. Only 10 of 56 CLL samples (18%) had no genomic abnormalities. Excluding the 4 common abnormalities mentioned above, 25 CLL samples (45%) had a total of 45 copy number changes detected by SNP-chip analysis. Four samples had 6q deletion at 6q21 that involved the AIM1 gene. UPD was detected in 4 samples; 2 samples involved whole chromosome 13 resulting in homozygous deletion of micro-RNA-15a (miR-15a)/miR-16-1. CLL samples with deletion of 13q14 and trisomy 12 were mutually exclusive.
CONCLUSIONS: Genetic abnormalities, including whole chromosome 13 UPD, are very common events in early-stage CLL. SNP-chip analysis can detect small genetic abnormalities in CLL and may be able to support or even supplant FISH and cytogenetics.
Tsuzuki S, Karnan S, Horibe K, et al.Genetic abnormalities involved in t(12;21) TEL-AML1 acute lymphoblastic leukemia: analysis by means of array-based comparative genomic hybridization.
Cancer Sci. 2007; 98(5):698-706 [PubMed
] Related Publications
The TEL (ETV6)-AML1 (RUNX1) chimeric gene fusion is the most common genetic abnormality in childhood acute lymphoblastic leukemias. Evidence suggests that this chimeric gene fusion constitutes an initiating mutation that is necessary but insufficient for the development of leukemia. In a search for additional genetic events that could be linked to the development of leukemia, we applied a genome-wide array-comparative genomic hybridization technique to 24 TEL-AML1 leukemia samples and two cell lines. It was found that at least two chromosomal imbalances were involved in all samples. Recurrent regions of chromosomal imbalance (>10% of cases) and representative involved genes were gain of chromosomes 10 (17%) and 21q (25%; RUNX1) and loss of 12p13.2 (87%; TEL), 9p21.3 (29%; p16INK4a/ARF), 9p13.2 (25%; PAX5), 12q21.3 (25%; BTG1), 3p21 (21%; LIMD1), 6q21 (17%; AIM1 and BLIMP1), 4q31.23 (17%; NR3C2), 11q22-q23 (13%; ATM) and 19q13.11-q13.12 (13%; PDCD5). Enforced expression of TEL and to a lesser extent BTG1, both single genes known to be located in their respective minimum common region of loss, inhibited proliferation of the TEL-AML1 cell line Reh. Together, these findings suggest that some of the genes identified as lost by array-comparative genomic hybridization may partly account for the development of leukemia.
Araki K, Nozaki K, Ueba T, et al.High expression of Aurora-B/Aurora and Ipll-like midbody-associated protein (AIM-1) in astrocytomas.
J Neurooncol. 2004 Mar-Apr; 67(1-2):53-64 [PubMed
] Related Publications
OBJECTIVE: Impaired regulation of Aurora-B/AIM-1 expression in human cells causes chromosomal abnormality and instability, and recent observations of high expression but not mutation of Aurora-B/AIM-1 in human cancers imply that Aurora-B/AIM-1 might be a candidate molecule for cancer progression. We analyzed the effects of modification of Aurora-B/AIM-1 expression on the growth of a human glioma cell line and the expression of Aurora-B/AIM-1 in astrocytomas.
METHODS: A glioma cell line, U251MG was transfected with wild type (WT) of Aurora-B/AIM-1 or kinase-inactive mutant of Aurora-B/AIM-1 in order to test the effects of overexpression of WT or kinase-inactive Aurora-B/AIM-1 on cell morphology and cell growth. Brain tissue samples were obtained during surgery and processed for reverse transcription-polymerase chain reaction, immunofluorescence in order to analyze the expression of Aurora-B/AIM-1 mRNA and protein.
RESULTS: Exogenous overexpression of WT of Aurora-B/AIM-1 in cultured cells of U251MG produced multinuclearity and increased ploidy, and inhibited the growth of tumor cells. Exogenous overexpression of kinase-inactive Aurora-B/AIM-1 in a human glioma cell line also suppressed the tumor cell growth without affecting ploidy. Aurora-B/AIM-1 was highly expressed in astrocytomas and U251MG, and mRNA and protein levels of Aurora-B/AIM-1 in tumor tissues well correlated with their histological malignancy (World Health Organization grading). Survival time also negatively correlated with the levels of Aurora-B/AIM-1 mRNA in tumor samples.
CONCLUSION: Aurora-B/AIM-1 was highly expressed in high-grade gliomas and its expression was well correlated with histological malignancy and clinical outcomes. The modification of the level of Aurora-B/AIM-1 expression might be a new target for glioma therapy.
Du J, Fisher DEIdentification of Aim-1 as the underwhite mouse mutant and its transcriptional regulation by MITF.
J Biol Chem. 2002; 277(1):402-6 [PubMed
] Related Publications
Animal pigmentation mutants have provided rich models for the identification of genes modulating pathways from melanocyte development to melanoma. One mouse model is the underwhite locus, alleles of which manifest altered pigmentation of both eye and fur, sometimes in an age-dependent fashion. Here we show that the mouse homolog of a recently identified gene whose mutation produces Japanese gold-colored fish, medaka b, maps to the mouse underwhite locus. We identify distinct mutations of this gene, known as Aim-1, in three underwhite mouse alleles and find that structure/function differences correlate with recessive versus dominant inheritance. The human ortholog of AIM-1 was originally identified as a melanocyte-restricted antigen that is recognized by autologous T cells from a patient with melanoma. We also provide evidence that AIM-1 is transcriptionally modulated by MITF, a melanocyte-specific transcription factor essential to pigmentation and a clinical diagnostic marker in human melanoma. Although AIM-1 appears to reside downstream of MITF, chromatin immunoprecipitations do not reveal binding of MITF to a 5'-flanking region containing histone 3 acetylation, indicating that MITF either acts indirectly on AIM-1 or it binds to a remote regulatory sequence. Nevertheless, MITF links AIM-1 expression and the underwhite phenotype to a transcriptional network central to pigmentation in mammals.
Recent advancement in the research of malignant melanoma is reviewed. Among many gene alterations detected in human melanoma, defect of CDKN2A located at chromosome 9p21 seems to be most important in the earlier developmental phase, though significance of this gene in the evolution of melanoma in situ has not been confirmed yet. Deletions of PTEN/MMAC1 on 10q23.3 and AIM1 on 6q21 as well as mutations of ras gene are involved in the later progression stages of melanoma. Adhesion molecules relevant to development and progression of melanoma have been intensely investigated in recent years, revealing crucial roles of cadherins and alpha(v)beta(3) integrin in the biologic behaviors of melanoma cells. Melanoma is characterized by extremely high potential of developing metastases. Dynamic changes of matrix metalloproteinase activity during invasion and movement of melanoma cells may be a major concern in this field. Fragility of blood vessels in melanoma lesions is another important point related to hematogeneous metastases. Acral lentiginous melanoma is a unique subtype of melanoma, because, in contrast to other subtypes, ultraviolet irradiation is not a major factor in its development. Investigation of pathogenesis of acral lentiginous melanoma surely provides us with new information about mechanism of melanocyte transformation. Recent advances in the management of malignant melanoma are also briefly reviewed, such as biochemotherapy, immunotherapy, and gene therapy. Finally, the concept of molecular classification of melanoma by gene expression profile is introduced, which possibly enables us to give the tailor-made therapy for each melanoma patient in the near future.
Harada M, Li YF, El-Gamil M, et al.Use of an in vitro immunoselected tumor line to identify shared melanoma antigens recognized by HLA-A*0201-restricted T cells.
Cancer Res. 2001; 61(3):1089-94 [PubMed
] Related Publications
An immunoselected melanoma cell line that had lost expression of the dominant melanoma antigens MART-1 and gp100 was generated in an attempt to identify previously unknown tumor antigens. After repeated stimulation with the autologous immunoselected tumor line, a number of HLA-A*0201-restricted T-cell clones were established from the peripheral blood of a single melanoma patient. One T-cell clone (C-22) recognized 14 of 16 HLA-A2+ melanoma cell lines, as well as HLA-A2+ melanocytes but recognized neither HLA-A2+ fibroblasts nor autologous B cells. Screening of an autologous cDNA library resulted in the isolation of a transcript identical to an entry in the expressed sequence tag database. Northern blot analysis revealed that this gene was expressed in most melanoma cell lines and melanocytes but not in normal tissues. The peptide epitope (AMF-GREFCYA) recognized by clone C-22 was identified based on studies of the recognition of truncated cDNAs and the use of the consensus HLAA*0201 binding motif. A second T-cell clone (C-29) was found to recognize a new tyrosinase-related protein 2 epitope (455-463; YAIDLPVSV) in an HLA-A*0201-restricted manner. Together, these results provide additional targets that can be used for the development of immunotherapeutic protocols in HLA-A2+ melanoma patients and demonstrate the utility of immunoselected tumor lines for the identification of new melanoma antigens.
Ray ME, Wistow G, Su YA, et al.AIM1, a novel non-lens member of the betagamma-crystallin superfamily, is associated with the control of tumorigenicity in human malignant melanoma.
Proc Natl Acad Sci U S A. 1997; 94(7):3229-34 [PubMed
] Free Access to Full Article Related Publications
AIM1 is a novel gene whose expression is associated with the experimental reversal of tumorigenicity of human malignant melanoma. The predicted protein product of the major 4.1-kb transcript shows striking similarity to the betagamma-crystallin superfamily. All known members of this superfamily contain two or four characteristic motifs arranged as one or two symmetrical domains. AIM1, in contrast, contains 12 betagamma motifs, suggesting a 6-domain structure resembling a trimer of beta- or gamma-crystallin subunits. The structure of the AIM1 gene shows remarkable similarity to beta-crystallin genes, with homologous introns delineating equivalent protein structural units. AIM1 is the first mammalian member of the betagamma superfamily with a primarily non-lens role. Other parts of the predicted AIM1 protein sequence have weak similarity with filament or actin-binding proteins. AIM1 is a good candidate for the putative suppressor of malignant melanoma on chromosome 6, possibly exerting its effects through interactions with the cytoskeleton.
Ray ME, Su YA, Meltzer PS, Trent JMIsolation and characterization of genes associated with chromosome-6 mediated tumor suppression in human malignant melanoma.
Oncogene. 1996; 12(12):2527-33 [PubMed
] Related Publications
Melanocytic transformation is thought to occur by the sequential accumulation of genetic alterations. Evidence implicating human chromosomes as a site for a gene(s) involved in melanoma suppression comes from studies of LOH [loss of heterozygosity], cytogenetics and biologic reversion of tumorigenicity following the introduction of a normal chromosome 6 by microcell-mediated chromosome transfer (Trent et al., 1990). Using a tumorigenic melanoma cell line (UACC 903) and a chromosome-6 suppressed melanoma subline [UACC 903 (+6)], we have isolated a series of genes uniquely expressed in the suppressed subline. A modified PCR-based cDNA subtraction technique was used to generate subtracted cDNA sublibraries for both the parental and (+6) suppressed cells. A total of 32 randomly selected clones from the suppressed sublibrary were isolated and examined, with 24 detecting a transcript by Northern analysis. Of these 24 clones, 21 (88%) demonstrated elevated expressed by Northern analysis in the suppressed subline relative to the tumorigenic parental cell line. In 6/21 differentially expressed clones (29%), expression was exclusive to the suppressed subline. Partial sequence analysis and database searching of these clones indicated that 5/6 were novel with one representing a previously characterized gene. Chromosomal localization of the five novel clones was performed following PCR amplification of a human/rodent somatic cell hybrid mapping panel or fluorescent in situ hybridization. One cDNA (termed AIM1) was localized to a band-region of chromosome 6 frequently deleted in melanomas (6q21). This novel approach should facilitate the identification of genes whose expression is causally related to the suppressed phenotype.