Research IndicatorsGraph generated 16 March 2017 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 16 March, 2017 using data from PubMed, MeSH and CancerIndex
Specific Cancers (6)
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
GEO Profiles, NCBI
Search the gene expression profiles from curated DataSets in the Gene Expression Omnibus (GEO) repository.
Latest Publications: THBS2 (cancer-related)
Zhuo C, Li X, Zhuang H, et al.Elevated THBS2, COL1A2, and SPP1 Expression Levels as Predictors of Gastric Cancer Prognosis.
Cell Physiol Biochem. 2016; 40(6):1316-1324 [PubMed
] Related Publications
BACKGROUND/AIMS: Gastric cancer (GC) is an important health problem. Classification based on molecular subtypes may help to determine the prognosis of patients with GC. Tumor invasion and metastasis are important factors affecting the prognosis of cancer. We aimed to identify genes related to tumor invasion and metastasis, which may serve as indicators of good GC prognosis.
METHODS: Tumor tissues and adjacent normal tissues were collected from 105 patients with primary GC who were treated by undergoing radical surgery. Samples were used for tissue microarray analysis. Identified genes with altered expression were further analyzed using the Gene Ontology (Go) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. The expression levels of THBS2, COL1A2 and SPP1 were analyzed by RT-PCR, western blot and immunohistochemistry. The overall survival curves of patients with high and low expression of each gene of interest were plotted and compared.
RESULTS: Forty-three genes were identified. THBS2, COL1A2 and SPP1 were selected for further analysis. Altered expression levels of THBS2, COL1A2 and SPP1 in tumor tissues were confirmed. Patients with low THBS2 expression had a better prognosis; the expression of COL1A2 and SPP1 might not affect the prognosis of patients with GC.
CONCLUSION: THBS2, but not COL1A2 and SPP1, may serve as an indicator of GC prognosis.
Yan L, Zhan C, Wang S, et al.Genetic analysis of radiation-specific biomarkers in sinonasal squamous cell carcinomas.
Tumour Biol. 2016; 37(9):12001-12009 [PubMed
] Related Publications
The aim of this study was to investigate the differences in the gene expression profiles of radiation-sensitive (RS) and radiation-resistant (RR) sinonasal squamous cell carcinoma (SNSCC) and to identify prognostic markers for the radiation reaction of SNSCC. We first examined the differentially expressed genes (DEGs) in RS and RR SNSCC tissues by analyzing clinical samples with GeneChip Human Transcriptome Array 2.0 (HTA 2.0).To understand the functional significance of the molecular changes, we examined the DEGs with Gene Ontology (GO) and pathway analyses to identify the core genes. The expression of several core genes (CCND2, COL5A2, GADD45B, and THBS2) was confirmed with reverse transcription quantitative PCR (RT-qPCR) in a larger series of tissues. We identified 208 DEGs, of which 76 were upregulated and 132 downregulated in the RS tissues relative to the RR tissues. The DEGs were mainly involved in the regulation of cell proliferation, the NF-kappaB signaling pathway, the cell adhesion molecule signaling pathway, and the extracellular matrix-receptor interaction signaling pathway. RT-qPCR confirmed that the CCND2, COL5A2, GADD45B, and THBS2 genes were significantly differentially expressed in the RS and RR tissues, consistent with the GeneChip data. These results extend our understanding of the molecular mechanisms underlying the sensitivity of SNSCC to radiation. The DEGs are involved in the differential response to radiation therapy and the dysregulated core genes identified in this study can be used to predict radiation sensitivity in SNSCC.
BACKGROUND: Colorectal cancer (CRC) development is accompanied by changes in expression for several genes; but the details of the underlying regulatory procesess remain unknown. Our aims were to assess the role of epigenetic processes in tumour formation and to identify characteristic DNA methylation and miRNA alterations in the colorectal adenoma-carcinoma sequence.
METHODS: Whole genome expression profiling was performed on colonic biopsy samples (49 healthy normal, 49 colorectal adenoma (AD), 49 CRC); on laser capture microdissected (LCM) epithelial and stromal cells from 6 CRC-normal adjacent tissue (NAT) samples pairs, and on demethylated human CRC cell lines using HGU133 Plus 2.0 microarrays (Affymetrix). Methylation status of genes with gradually altering expression along the AD-CRC sequence was further analysed on 10-10 macrodissected and 5-5 LCM samples from healthy colon, from adenoma and from CRC biopsy samples using bisulfite-sequencing PCR (BS-PCR) followed by pyrosequencing. In silico miRNA prediction for the selected genes was performed with miRWALK algorithm, miRNA expression was analysed on 3 CRC-NAT sample pairs and 3 adenoma tissue samples using the Human Panel I + II (Exiqon). SFRP1 immunohistochemistry experiments were performed.
RESULTS: A set of transcripts (18 genes including MAL, SFRP1, SULT1A1, PRIMA1, PTGDR) showed decreasing expression (p < 0.01) in the biopsy samples along the adenoma-carcinoma sequence. Three of those (COL1A2, SFRP2, SOCS3) showed hypermethylation and THBS2 showed hypomethylation both in AD and in CRC samples compared to NAT, while BCL2, PRIMA1 and PTGDR showed hypermethylation only in the CRC group. miR-21 was found to be significantly (p < 0.01) upregulated in adenoma and tumour samples compared to the healthy colonic tissue controls and could explain the altered expression of genes for which DNA methylation changes do not appear to play role (e.g. BCL2, MAL, PTGS2). Demethylation treatment could upregulate gene expression of genes that were found to be hypermethylated in human CRC tissue samples. Decreasing protein levels of SFRP1 was also observed along the adenoma-carcinoma sequence.
CONCLUSION: Hypermethylation of the selected markers (MAL, PRIMA1, PTGDR and SFRP1) can result in reduced gene expression and may contribute to the formation of colorectal cancer.
Tian ZQ, Li ZH, Wen SW, et al.Identification of Commonly Dysregulated Genes in Non-small-cell Lung Cancer by Integrated Analysis of Microarray Data and qRT-PCR Validation.
Lung. 2015; 193(4):583-92 [PubMed
] Related Publications
BACKGROUND: Non-small-cell lung cancer (NSCLC), the most common lung cancer, leads to the largest number of cancer-related deaths worldwide. There are many studies to identify the differentially expressed genes (DEGs) between NSCLC and normal control (NC) tissues by means of microarray technology. Because of the inconsistency of the microarray data sets, we performed an integrated analysis to identify DEGs and analyzed their biological function.
METHODS AND RESULTS: We combined 15 microarray data sets and identified 1063 DEGs between NSCLC and NC tissues; in addition, we found that the DEGs were enriched in regulation of cell proliferation process and focal adhesion signaling pathway. The protein-protein interaction network analysis for the top 20 significantly DEGs revealed that CAV1, COL1A1, and ADRB2 were the significant hub proteins. Finally, we employed qRT-PCR to validate the meta-analysis approach by determining the expression of the top 10 most significantly DEGs and found that the expression of these genes were significantly different between tumor and NC tissues, in accordance with the results of meta-analysis.
CONCLUSION: qRT-PCR results indicated that the meta-analysis approach in our study was acceptable. Our data suggested that some of the DEGs, including MMP12, COL11A1, THBS2, FAP, and CAV1, may participate in the pathology of NSCLC and could be applied as potential markers or therapeutic targets for NSCLC.
Melaiu O, Melissari E, Mutti L, et al.Expression status of candidate genes in mesothelioma tissues and cell lines.
Mutat Res. 2015; 771:6-12 [PubMed
] Related Publications
In order to broaden knowledge on the pathogenesis of malignant pleural mesothelioma (MPM), we reviewed studies on the MPM-transcriptome and identified 119 deregulated genes. However, there was poor consistency among the studies. Thus, the expression of these genes was further investigated in the present work using reverse transcriptase-quantitative PCR (RT-qPCR) in 15 MPM and 20 non-MPM tissue samples. Fifty-nine genes showed a statistically significant deregulation and were further evaluated in two epithelioid MPM cell lines (compared to MET-5A, a non-MPM cell line). Nine genes (ACSL1, CCNO, CFB, PDGFRB, SULF1, TACC1, THBS2, TIMP3, XPOT) were deregulated with statistical significance in both cell lines, 12 (ASS1, CCNB1, CDH11, COL1A1, CXADR, EIF4G1, GALNT7, ITGA4, KRT5, PTGIS, RAN, SOD1) in at least one cell line, whereas 7 (DSP, HEG1, MCM4, MSLN, NME2, NMU, TNPO2) were close but did not reach the statistical significance in any of the cell line. Patients whose MPM tissues expressed elevated mRNA levels of BIRC5, DSP, NME2, and THBS2 showed a statistically significant shorter overall survival. Although MPM is a poorly studied cancer, some features are starting to emerge. Novel cancer genes are suggested here, in particular those involved in cell-cell and cell-matrix interactions.
Zubor P, Hatok J, Moricova P, et al.Gene expression abnormalities in histologically normal breast epithelium from patients with luminal type of breast cancer.
Mol Biol Rep. 2015; 42(5):977-88 [PubMed
] Related Publications
The gene expression profile of breast cancer has been described as a great breakthrough on the way to comprehend differences in cancer origin, behavior and therapy. However, gene expression profile in histologically normal epithelium (HNEpi) which could harbor genetic abnormalities predisposing breast tissue to develop malignancy was minor scope for scientists in the past. Thus, we aimed to analyze gene expressions in HNEpi and breast cancer tissue (BCTis) in order to establish its value as potential diagnostic marker for cancer development. We evaluated a panel of disease-specific genes in luminal type (A/B) of breast cancer and tumor surrounding HNEpi by qRT-PCR Array in 32 microdissected samples. There was 20.2 and 2.4% deregulation rate in genes with at least 2-fold or 5-fold over-expression between luminal (A/B) type breast carcinomas and tumor surrounding HNEpi, respectively. The high-grade luminal carcinomas showed higher number of deregulated genes compared to low-grade cases (50.6 vs. 23.8% with at least 2-fold deregulation rate). The main overexpressed genes in HNEpi were KLK5, SCGB1D2, GSN, EGFR and NGFR. The significant differences in gene expression between BCTis and HNEpi samples were revealed for BAG1, C3, CCNA2, CD44, FGF1, FOSL1, ID2, IL6R, NGFB, NGFR, PAPPA, PLAU, SERPINB5, THBS1 and TP53 gene (p < 0.05) and BCL2L2, CTSB, ITGB4, JUN, KIT, KLF5, SCGB1D2, SCGB2A1, SERPINE1 (p < 0.01), and EGFR, GABRP, GSN, MAP2K7 and THBS2 (p < 0.001), and GSN, KLK5 (p < 0.0001). The ontological gene analyses revealed high deregulations in gene group directly associated with breast cancer prognosis and origin.
BACKGROUND: Thrombospondins (THBSs) are a family of multidomain and secreted matricellular Ca(2+)-binding glycoproteins which has at least five members encoded by independent genes. As a THBSs family member, Thrombospondin2 (THBS2) has been reported to regulate angiogenesis. Nevertheless, the functions and clinical significance of THBS2 still remains unclear in gastric cancer.
METHODS: The mRNA and protein expression levels of THBS2 were assessed in 14 paired of gastric cancer specimens and corresponding normal mucosas using quantitative real-time PCR and western blot analysis. Immunohistochemistry of THBS2 and CD34 on population-based tissue microarrays consisting of 129 gastric cancer cases were used to evaluate the prognostic significance of THBS2 and microvessel density (MVD) of each sample. Survival analyses were performed by Kaplan-Meier method and Cox's proportional hazards model. Colony formation assay, endothelial cell tube formation assay, cell migration assay and apoptosis analysis in MKN-45 and SGC-7901 cell lines were carried out to evaluate the effects of THBS2 on gastric cancer in vitro.
RESULTS: 85.71% (12 of 14) gastric cancer tissues expressed remarkably lower THBS2 in both mRNA and protein levels than the corresponding normal controls. Consistently, tissue microarray (TMA) results showed THBS2 levels were also inhibited in gastric cancer tissues compared with the normal controls. Moreover, we observed that patients with higher levels of THBS2 were significantly correlated with more favourable prognosis while decreased THBS2 expression were associated with poorer histological grades of gastric cancer. Additionally, our in vitro experiments further demonstrated that overexpression of THBS2 could impede both the proliferation rate and the tube formation of Human umbilical vein endothelial cells (HUVECs) in MKN-45 and SGC-7901 cell lines.
CONCLUSION: Our study suggests THBS2 is aberrantly expressed in gastric cancer and plays a critical role in cancer progression, which can be a potential prognosis predictor of gastric cancer.
Chen J, Yao D, Zhao S, et al.MiR-1246 promotes SiHa cervical cancer cell proliferation, invasion, and migration through suppression of its target gene thrombospondin 2.
Arch Gynecol Obstet. 2014; 290(4):725-32 [PubMed
] Related Publications
PURPOSE: To investigate the effects of miR-1246 on proliferation, invasion, and migration in the human (CSCC) cell line SiHa.
METHODS: SiHa cells were assigned into three groups: miR-1246 analog; miR-1246 antagonist; and control. The MTT, transwell, and wound healing assays were performed to evaluate the proliferation, invasion, and migration abilities of SiHa cells, respectively. Western blot was carried out to detect protein expression of thrombospondin-2 (THBS2) before and after transfection with miR-1246 analog, antagonist, or control. In addition, a THBS2 3'-UTR-containing dual luciferase plasmid was generated and co-transfected with miR-1246, the inhibitor, or non-specific miRNA, into SiHa cells to observe its effects on THBS2-driven luciferase enzyme activity.
RESULTS: MTT, transwell, and wound healing assays revealed that proliferation, migration, and invasion were all significantly enhanced (P < 0.01) in SiHa cells transfected with miR-1246 analog, but were suppressed in those transfected with the miR-1246 antagonist. Western blot data showed that miR-1246 analog-transfected SiHa cells had significantly decreased THBS2 expression when compared with control-transfected cells (gray value = 6.28 ± 10.22 vs. 9.58 ± 17.58; P = 0.013) while those transfected with the miR-1246 antagonist had significantly increased THBS2 expression (gray value = 12.90 ± 19.81; P = 0.037). Moreover, SiHa cells co-transfected with miR-1246 and the THBS2 3'-UTR-containing plasmid exhibited decreased luciferase enzyme activity compared with the control.
CONCLUSION: MiR-1246 induced CSCC SiHa cell proliferation, invasion and migration. Preliminary evidence suggests that miR-1246 might promote CSCC tumorigenesis and progression by the suppression of its target gene THBS2.
Noorlag R, van der Groep P, Leusink FK, et al.Nodal metastasis and survival in oral cancer: Association with protein expression of SLPI, not with LCN2, TACSTD2, or THBS2.
Head Neck. 2015; 37(8):1130-6 [PubMed
] Related Publications
BACKGROUND: Gene expression profiling revealed a strong signature predicting lymph node metastases in oral squamous cell carcinoma (OSCC). Four of the most predictive genes are secretory leukocyte protease inhibitor (SLPI), lipocalin-2 (LCN2), thrombospondin-2 (THBS2), and tumor-associated calcium signal transducer 2 (TACSTD2). This study correlates their protein expression with lymph node metastases, overall survival (OS), and disease-specific survival (DSS).
METHODS: Two hundred twelve patients with OSCC were included for protein expression analysis by immunohistochemistry.
RESULTS: SLPI expression correlates with lymph node metastases in the whole cohort, not in a subgroup of cT1 to 2N0. SLPI expression correlates with OS (hazard ratio [HR] = 0.61) and DSS (HR = 0.47) in multivariate analysis. LCN2, THBS2, and TACSTD2 show no correlation with lymph node metastases, OS, or DSS.
CONCLUSION: Although SLPI expression correlates with lymph node metastases, it has no additional value in determining lymph node metastases in early oral cancer. However, it is an independent predictor for both OS and DSS and therefore a relevant prognostic biomarker in OSCC.
Slavin S, Yeh CR, Da J, et al.Estrogen receptor α in cancer-associated fibroblasts suppresses prostate cancer invasion via modulation of thrombospondin 2 and matrix metalloproteinase 3.
Carcinogenesis. 2014; 35(6):1301-9 [PubMed
] Free Access to Full Article Related Publications
The prostate cancer (PCa) microenvironment contains active stromal cells known as cancer-associated fibroblasts (CAF) that may play important roles in influencing tumor progression. Here we studied the role of CAF estrogen receptor alpha (ERα) and found that it could protect against PCa invasion. Immunohistochemistry on prostatectomy specimens showed that PCa patients with ERα-positive stroma had a significantly lower risk for biochemical recurrence. In vitro invasion assays further confirmed that the stromal ERα was able to reduce PCa cell invasion. Dissection of the molecular mechanism revealed that the CAF ERα could function through a CAF-epithelial interaction via selectively upregulating thrombospondin 2 (Thbs2) and downregulating matrix metalloproteinase 3 (MMP3) at the protein and messenger RNA levels. Chromatin immunoprecipitation assays further showed that ERα could bind to an estrogen response element on the promoter of Thbs2. Importantly, knockdown of Thbs2 led to increased MMP3 expression and interruption of the ERα mediated invasion suppression, providing further evidence of an ERα-Thbs2-MMP3 axis in CAF. In vivo studies using athymic nude mice injected with CWR22Rv1 (22Rv1) PCa epithelial cells and CAF cells ± ERα also confirmed that mice coimplanted with PCa cells and CAF ERα+ cells had less tumor foci in the pelvic lymph nodes, less metastases, and tumors showed less angiogenesis, MMP3, and MMP9 (an MMP3 downstream target) positive staining. Together, these data suggest that CAF ERα could play protective roles in suppressing PCa metastasis. Our results may lead to developing new and alternative therapeutic approaches to battle PCa via controlling ERα signaling in CAF.
PURPOSE: To elucidate molecular pathways contributing to metastatic cancer progression and poor clinical outcome in serous ovarian cancer.
EXPERIMENTAL DESIGN: Poor survival signatures from three different serous ovarian cancer datasets were compared and a common set of genes was identified. The predictive value of this gene signature was validated in independent datasets. The expression of the signature genes was evaluated in primary, metastatic, and/or recurrent cancers using quantitative PCR and in situ hybridization. Alterations in gene expression by TGF-β1 and functional consequences of loss of COL11A1 were evaluated using pharmacologic and knockdown approaches, respectively.
RESULTS: We identified and validated a 10-gene signature (AEBP1, COL11A1, COL5A1, COL6A2, LOX, POSTN, SNAI2, THBS2, TIMP3, and VCAN) that is associated with poor overall survival (OS) in patients with high-grade serous ovarian cancer. The signature genes encode extracellular matrix proteins involved in collagen remodeling. Expression of the signature genes is regulated by TGF-β1 signaling and is enriched in metastases in comparison with primary ovarian tumors. We demonstrate that levels of COL11A1, one of the signature genes, continuously increase during ovarian cancer disease progression, with the highest expression in recurrent metastases. Knockdown of COL11A1 decreases in vitro cell migration, invasion, and tumor progression in mice.
CONCLUSION: Our findings suggest that collagen-remodeling genes regulated by TGF-β1 signaling promote metastasis and contribute to poor OS in patients with serous ovarian cancer. Our 10-gene signature has both predictive value and biologic relevance and thus may be useful as a therapeutic target.
Epigenomic markers can identify tumor subtypes, but few platforms can accommodate formalin-fixed paraffin-embedded (FFPE) tumor tissue. We tested different amounts of bisulfite-converted (bs) DNA from six FFPE ovarian carcinomas (OC) of serous, endometrioid, and clear cell histologies and two HapMap constitutional genomes to evaluate the performance of the GoldenGate methylation assay. Methylation status at each 1,505 CpG site was expressed as β-values. Comparing 400 ng versus 250 ng bsDNA, reproducibility of the assay ranged from Spearman r(2) = 0.41 to 0.90, indicating that β-values obtained with a lower DNA amount did not always correlate well with the higher amount. Average methylation for the six samples was higher using 250 ng (β-value = 0.45, SD = 0.29) than with 400 ng (β-value = 0.36, SD = 0.32). Reproducibility between duplicate HapMap samples (r(2) = 0.76 to 0.92) was also variable. Using 400 ng input bsDNA, THBS2 and ERG were differentially methylated across all histologic types and between endometrioid and clear cell types at <0.1% false discovery rate. Methylation did not always correlate with gene expression (r(2) = -0.70 to 0.15). We found that lower bsDNA overestimates methylation, and, using higher bsDNA amounts, we confirmed a previous report of higher methylation of THBS2 in clear cell OC, which could provide new insight into biological pathways that distinguish OC histological types.
Gardi NL, Deshpande TU, Kamble SC, et al.Discrete molecular classes of ovarian cancer suggestive of unique mechanisms of transformation and metastases.
Clin Cancer Res. 2014; 20(1):87-99 [PubMed
] Related Publications
PURPOSE: Tumor heterogeneity and subsistence of high-grade serous ovarian adenocarcinoma (HGSC) classes can be speculated from clinical incidences suggesting passive tumor dissemination versus active invasion and metastases.
EXPERIMENTAL DESIGN: We explored this theme toward tumor classification through two approaches of gene expression pattern clustering: (i) derivation of a core set of metastases-associated genes and (ii) resolution of independent weighted correlation networks. Further identification of appropriate cell and xenograft models was carried out for resolution of class-specific biologic functions.
RESULTS: Both clustering approaches achieved resolution of three distinct tumor classes, two of which validated in other datasets. Networks of enriched gene modules defined biologic functions of quiescence, cell division-differentiation-lineage commitment, immune evasion, and cross-talk with niche factors. Although deviant from normal homeostatic mechanisms, these class-specific profiles are not totally random. Preliminary validation of these suggests that Class 1 tumors survive, metastasize in an epithelial-mesenchymal transition (EMT)-independent manner, and are associated with a p53 signature, aberrant differentiation, DNA damage, and genetic instability. These features supported by association of cell-specific markers, including PAX8, PEG3, and TCF21, led to the speculation of their origin being the fimbrial fallopian tube epithelium. On the other hand, Class 2 tumors activate extracellular matrix-EMT-driven invasion programs (Slug, SPARC, FN1, THBS2 expression), IFN signaling, and immune evasion, which are prospectively suggestive of ovarian surface epithelium associated wound healing mechanisms. Further validation of these etiologies could define a new therapeutic framework for disease management.
Matos AR, Coutinho-Camillo CM, Thuler LC, et al.Expression analysis of thrombospondin 2 in prostate cancer and benign prostatic hyperplasia.
Exp Mol Pathol. 2013; 94(3):438-44 [PubMed
] Related Publications
Thrombospondin 2 (TSP2) is a protein with important roles in different tumor types, mainly related to tumor inhibition. However, there are limiting data regarding TSP2 in prostate cancer (PCa) and benign prostatic hyperplasia (BPH). We aimed to investigate TSP2 transcript and protein expression in tumoral and non-tumoral prostate tissues and cell lines, and its implications for PCa diagnosis and progression. TSP2 transcript expression was evaluated by real time PCR in PCa and BPH tissue samples and in tumoral and non-tumoral cell lines. TSP2 protein expression analysis was conducted by immunohistochemistry in a tissue microarray (TMA) containing PCa and BPH tissue samples. TSP2 transcript was down-regulated in PCa tissue samples and cell lines, when compared to BPH and non-tumoral samples (P<0.01). Receiver Operating Curve (ROC) analysis demonstrated that TSP2 transcript levels can better distinguish PCa from BPH tissue samples (P<0.01) than serum PSA levels (P=0.299). TSP2 protein expression has been observed in the cytoplasm of both PCa and BPH epithelial and stromal compartments. TSP2 stromal staining scores were significantly lower in PCa than in BPH tissues (P<0.01), while similar TSP2 epithelial staining patterns were observed in both diseases. Notably, the TSP2 epithelial staining score was significantly correlated to vascular invasion and biochemical recurrence in PCa tissue samples (P<0.05). Our data indicate that TSP2 is down-regulated at PCa tissues and cell lines, especially at stroma compartment, which could be related to PCa progression. TSP2 levels could potentially be applied for differential PCa and BPH diagnosis.
Agostini J, Benoist S, Seman M, et al.Identification of molecular pathways involved in oxaliplatin-associated sinusoidal dilatation.
J Hepatol. 2012; 56(4):869-76 [PubMed
] Related Publications
BACKGROUND & AIMS: Oxaliplatin-based chemotherapy for colorectal liver metastases (CRLM) can result in vascular liver lesions such as sinusoidal dilatations. Physiopathology remains unclear and variability between patients suggests that there is individual susceptibility. A better understanding of the molecular mechanisms of oxaliplatin liver toxicity may allow the identification of biomarkers and adaptation of chemotherapy delivery.
METHODS: Between 1998 and 2009, 83 non-tumor frozen liver samples were obtained from patients operated on for CRLM after an exclusive oxaliplatin-based chemotherapy. Gene-expression profiles were first analyzed by microarray on a selected population of 19 patients: 9 patients with severe sinusoidal dilatation after a short period of chemotherapy and 10 patients without any sinusoidal dilatation after a long period of chemotherapy. These were compared with a control group of 5 patients without any chemotherapy and lesions. Twenty-two differentially-expressed (at least 1.5-fold difference in expression) genes were selected. These were validated using microfluidic quantitative RT-PCR in an independent set of 58 patients (28 with sinusoidal dilatation and 30 without sinusoidal dilatation).
RESULTS: Among the 22 selected genes, 12 were validated as being up-regulated in samples from patients with sinusoidal dilatation compared to patients without sinusoidal dilatation. Genes involved in angiogenesis (VEGFD, THY-1, GPNMB) and cellular adhesion (VWF, CDH13, THBS2), and extracellular matrix components (COL1A1, COL4A1, SLCO1A2) were over-represented in patients with sinusoidal dilatation.
CONCLUSIONS: This molecular signature confirms the involvement of angiogenesis and coagulation in sinusoidal injuries induced by oxaliplatin and reinforces a potential protective role of bevacizumab and aspirin, as suggested in retrospective clinical studies.
BACKGROUND: Oral Squamous Cell Carcinoma (OSCC) is a major cause of cancer death worldwide, which is mainly due to recurrence leading to treatment failure and patient death. Histological status of surgical margins is a currently available assessment for recurrence risk in OSCC; however histological status does not predict recurrence, even in patients with histologically negative margins. Therefore, molecular analysis of histologically normal resection margins and the corresponding OSCC may aid in identifying a gene signature predictive of recurrence.
METHODS: We used a meta-analysis of 199 samples (OSCCs and normal oral tissues) from five public microarray datasets, in addition to our microarray analysis of 96 OSCCs and histologically normal margins from 24 patients, to train a gene signature for recurrence. Validation was performed by quantitative real-time PCR using 136 samples from an independent cohort of 30 patients.
RESULTS: We identified 138 significantly over-expressed genes (> 2-fold, false discovery rate of 0.01) in OSCC. By penalized likelihood Cox regression, we identified a 4-gene signature with prognostic value for recurrence in our training set. This signature comprised the invasion-related genes MMP1, COL4A1, P4HA2, and THBS2. Over-expression of this 4-gene signature in histologically normal margins was associated with recurrence in our training cohort (p = 0.0003, logrank test) and in our independent validation cohort (p = 0.04, HR = 6.8, logrank test).
CONCLUSION: Gene expression alterations occur in histologically normal margins in OSCC. Over-expression of the 4-gene signature in histologically normal surgical margins was validated and highly predictive of recurrence in an independent patient cohort. Our findings may be applied to develop a molecular test, which would be clinically useful to help predict which patients are at a higher risk of local recurrence.
Insulin-like growth factor-binding protein-3 (IGFBP-3) expression is frequently suppressed in liver cancers and can be reactivated by histone deacetylase (HDAC) inhibition. This study examined the role of IGFBP-3 in mediating the effects of the HDAC inhibitor MS-275 in liver cancer cells and identified IGFBP-3-dependent proteins that regulate proliferation and migration. In HepG2 cells, MS-275 inhibited DNA synthesis, cell cycle activity, and cell viability concomitantly with increased binding of acetylated histone H3 to IGFBP-3 promoter sequences and induction of IGFBP-3 expression. IGFBP-3 down-regulation by siRNA significantly reversed the inhibition of cell viability and DNA synthesis by MS-275, indicating an intermediary role for IGFBP-3. Induction of the cyclin-dependent kinase inhibitor p21 by MS-275 was attenuated by IGFBP-3 down-regulation, providing an explanation for IGFBP-3-dependent effects of MS-275 on cell cycle activity. In contrast, MS-275 stimulated HepG2 cell migration, an effect also inhibited by IGFBP-3 down-regulation. Among genes whose induction by MS-275 was attenuated by IGFBP-3 down-regulation, LYVE1 and THBS2 (thrombospondin-2) were identified as mediators of IGFBP-3-dependent effects of MS-275. Silencing of either protein had no effect on the inhibition of HepG2 viability by MS-275 but reversed its stimulatory effect on cell migration. We conclude that among genes up-regulated by MS-275, IGFBP-3 is a key mediator of effects on hepatoma cell growth and migration, involving IGFBP-3-dependent proteins p21 (proliferation) and LYVE1 and THBS2 (migration). The enhanced cell motility that accompanies reactivation of IGFBP-3 expression in liver cancer by HDAC inhibition suggests the possibility of increased metastatic spread despite inhibited cell proliferation.
BACKGROUND: Our previous studies showed that Salvianolic acid B (Sal B) inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters and such anti-cancer effects might be related to the inhibition of angiogenesis. This study was aimed to further investigate the anti-proliferative effect of Sal B on the most common type of oral cancer, oral squamous cell carcinoma (OSCC) and the possible mechanisms of action with respect to angiogenesis inhibition.
METHODS: Two well-characterized oral squamous cell carcinoma cell lines, CAL27 and SCC4, and premalignant leukoplakia cells were treated with different concentrations of Sal B. Cytotoxicity was assessed by MTT assay. cDNA microarray was utilized to evaluate the expression of 96 genes known to be involved in modulating the biological processes of angiogenesis. Real-time reverse transcription-polymerase chain reaction analysis was conducted to confirm the cDNA microarray data.
RESULTS: Sal B induced growth inhibition in OSCC cell lines but had limited effects on premalignant cells. A total of 17 genes showed a greater than 3-fold change when comparing Sal B treated OSCC cells to the control. Among these genes, HIF-1α, TNFα and MMP9 are specifically inhibited, expression of THBS2 was up-regulated.
CONCLUSIONS: Sal B has inhibitory effect on OSCC cell growth. The antitumor effect can be attributed to anti-angiogenic potential induced by a decreased expression of some key regulator genes of angiogenesis. Sal B may be a promising modality for treating oral squamous cell carcinoma.
BACKGROUND: A recently developed probe-based technology, the NanoString nCounter™ gene expression system, has been shown to allow accurate mRNA transcript quantification using low amounts of total RNA. We assessed the ability of this technology for mRNA expression quantification in archived formalin-fixed, paraffin-embedded (FFPE) oral carcinoma samples.
RESULTS: We measured the mRNA transcript abundance of 20 genes (COL3A1, COL4A1, COL5A1, COL5A2, CTHRC1, CXCL1, CXCL13, MMP1, P4HA2, PDPN, PLOD2, POSTN, SDHA, SERPINE1, SERPINE2, SERPINH1, THBS2, TNC, GAPDH, RPS18) in 38 samples (19 paired fresh-frozen and FFPE oral carcinoma tissues, archived from 1997-2008) by both NanoString and SYBR Green I fluorescent dye-based quantitative real-time PCR (RQ-PCR). We compared gene expression data obtained by NanoString vs. RQ-PCR in both fresh-frozen and FFPE samples. Fresh-frozen samples showed a good overall Pearson correlation of 0.78, and FFPE samples showed a lower overall correlation coefficient of 0.59, which is likely due to sample quality. We found a higher correlation coefficient between fresh-frozen and FFPE samples analyzed by NanoString (r = 0.90) compared to fresh-frozen and FFPE samples analyzed by RQ-PCR (r = 0.50). In addition, NanoString data showed a higher mean correlation (r = 0.94) between individual fresh-frozen and FFPE sample pairs compared to RQ-PCR (r = 0.53).
CONCLUSIONS: Based on our results, we conclude that both technologies are useful for gene expression quantification in fresh-frozen or FFPE tissues; however, the probe-based NanoString method achieved superior gene expression quantification results when compared to RQ-PCR in archived FFPE samples. We believe that this newly developed technique is optimal for large-scale validation studies using total RNA isolated from archived, FFPE samples.
Metodieva SN, Nikolova DN, Cherneva RV, et al.Expression analysis of angiogenesis-related genes in Bulgarian patients with early-stage non-small cell lung cancer.
Tumori. 2011 Jan-Feb; 97(1):86-94 [PubMed
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AIMS AND BACKGROUND: Angiogenesis is a key process in the early stages of tumor development. In this study we aimed to evaluate the expression of a panel of angiogenesis-related genes in a group of Bulgarian patients with early-stage non-small cell lung cancer (NSCLC).
METHODS AND STUDY DESIGN: We analyzed the expression of 84 genes associated with the angiogenic process in 12 NSCLCs of two histological subtypes: 7 adenocarcinomas and 5 squamous cell carcinomas. Eight peripheral nontumorous tissues were used as controls. We performed real-time PCR on pathway-specific gene arrays (SABiosciences).
RESULTS: Our pilot study identified upregulated genes in early-stage NSCLC including growth factors (TGFA and EFNA3), the adhesion molecule THBS2, cytokines and chemokines (MDK, CXCL9, CXCL10), and the serine protease PLAU. Several genes showed downregulation including one growth factor (FIGF), the receptors for growth factors TEK and S1PR1 as well as adhesion molecules (COL4A3 and CDH5), the cytokine IL6, the matrix protein LEP and the transcription factor NOTCH4. The study demonstrated deregulated genes specific for the two histological subtypes including the transcription factor HAND2, which was overexpressed in squamous cell carcinomas but not adenocarcinomas.
CONCLUSIONS: Despite the limited number of patients, our results demonstrated the potential of angiogenesis-related genes as biomarkers in the early stages of NSCLC development.
BACKGROUND: Despite extensive research, the details of the biological mechanisms by which cancer cells acquire motility and invasiveness are largely unknown. This study identifies an invasion associated gene signature shedding light on these mechanisms.
METHODS: We analyze data from multiple cancers using a novel computational method identifying sets of genes whose coordinated overexpression indicates the presence of a particular phenotype, in this case high-stage cancer.
RESULTS: We conclude that there is one shared "core" metastasis-associated gene expression signature corresponding to a specific variant of stromal desmoplastic reaction, present in a large subset of samples that have exceeded a threshold of invasive transition specific to each cancer, indicating that the corresponding biological mechanism is triggered at that point. For example this threshold is reached at stage IIIc in ovarian cancer and at stage II in colorectal cancer. Therefore, its presence indicates that the corresponding stage has been reached. It has several features, such as coordinated overexpression of particular collagens, mainly COL11A1 and other genes, mainly THBS2 and INHBA. The composition of the overexpressed genes indicates invasion-facilitating altered proteolysis in the extracellular matrix. The prominent presence in the signature of INHBA in all cancers strongly suggests a biological mechanism centered on activin A induced TGF-β signaling, because activin A is a member of the TGF-β superfamily consisting of an INHBA homodimer. Furthermore, we establish that the signature is predictive of neoadjuvant therapy response in at least one breast cancer data set.
CONCLUSIONS: Therefore, these results can be used for developing high specificity biomarkers sensing cancer invasion and predicting response to neoadjuvant therapy, as well as potential multi-cancer metastasis inhibiting therapeutics targeting the corresponding biological mechanism.
Chijiwa T, Abe Y, Ikoma N, et al.Thrombospondin 2 inhibits metastasis of human malignant melanoma through microenvironment-modification in NOD/SCID/gammaCnull (NOG) mice.
Int J Oncol. 2009; 34(1):5-13 [PubMed
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Thrombospondin (TSP) 2 interacts with matrix metalloproteinases (MMPs) and matrix serine proteases such as plasminogen activator (PA). Malignant melanoma is an aggressive human neoplasm showing aggressive metastatic features. We examined the effects of TSP2 gene introduction in the human malignant melanoma cell line A375. We established three clones transfected with human TSP2 (A375/TSP2). The in vitro invasiveness was remarkably suppressed (42-61%) in the TSP2-transfectants, while growth properties were preserved. The A375/TSP2 showed significantly decreased liver metastatic potential (liver weight: 3.88+/-0.30 g in A375/TSP2, 7.07+/-0.67 g in vector-transfectant (A375/V), p<0.01, Mann-Whitney U test) in super immuno-deficient mice (NOD/SCID/gammacnull, NOG). The PA inhibitor-1 (PAI-1) and PAI-2 mRNAs were significantly overexpressed in A375/TSP2. The increased activities of PAI-1 and PAI-2 were confirmed by reverse zymography. The vascularity of metastatic lesions was significantly decreased in A375/TSP2 (vascular density: 0.62+/-0.15% in A375/TSP2, 4.96+/-0.61% in A375/V, p<0.01, Welch test). These results suggest that TSP2 suppresses hematogenous metastasis through microenvironment-modification including PAI up-regulation and anti-vascularization in human malignant melanoma.
Czekierdowski A, Czekierdowska S, Danilos J, et al.Microvessel density and CpG island methylation of the THBS2 gene in malignant ovarian tumors.
J Physiol Pharmacol. 2008; 59 Suppl 4:53-65 [PubMed
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We aimed to investigate the role of thrombospondin-2 (THBS2) related angiogenic activity in malignant ovarian tumors and to determine if aberrant methylation associated inactivation is involved in down-regulating THBS2 expression in ovarian cancer. The methylation status of the THBS2 promoter region and microvessel density (MVD) was studied in 70 malignant ovarian tumors and in 15 control ovarian samples. A methylation specific PCR (MSP) method was used to distinguish methylated from unmethylated DNA in the promoter regions of the THBS2 gene. MVD was assessed with anti-CD34 antibodies and the results were compared between tumors with average (AVD) and high (HVD) microvessel density. Alterations in the expression of trombospondin-2 were more often seen in early (FIGO stage I and II ) than in late stage tumors (66% vs. 30%, p=0.01). Age, menopausal status, the histological type and tumor grade did not correlate with thrombospondin-2 expression, however, silencing of THBS2 gene was more often seen in higher rather than in lower grade (50% vs. 28%) cancers and in nonserous rather than in serous (43% vs. 32%) tumors. In 81% of THBS2 mRNA-negative tumors, ahypermethylated promoter region of THBS2 was found (p=0.00003). An unmethylated product of the MSP reaction was more often detected in high grade tumors (93% vs. 76%, p=0.04). The incidence of THBS2 hypermethylation was not related to the tumor histological type, but unmethylated THBS2 was more often found in serous rather than in nonserous tumor (96% vs. 74%, p=0.01). The median MVD in malignant the tumor samples was 21,7 (range: 7.6-55.2). In the group with HVD, 54% were THBS2 mRNAnegative, conversely, in the group with AVD tumors only 26% of the cases had undetectable THSB2 mRNA. A significant correlation between microvessel density and the expression of trombospondin-2 (p=0.009) was found. In the samples with HVD, 51% had hypermethylated THBS2, however methylation pattern had no significant influence on microvessel density. In conclusion, hypermethylation might be responsible for altered expression of thrombospondin-2 in ovarian cancer. The THSB2 methylation pattern had no significant influence on microvessel density.
Rendtlew Danielsen JM, Knudsen LM, Dahl IM, et al.Dysregulation of CD47 and the ligands thrombospondin 1 and 2 in multiple myeloma.
Br J Haematol. 2007; 138(6):756-60 [PubMed
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CD47 and thrombospondin 1 and 2 (TSP1 and TSP2) expression were analysed by real-time reverse transcription polymerase chain reaction in fluorescence-activated cell sorted plasma cells (PCs) from patients at consecutive stages of multiple myeloma (MM) development. 80% of MM patients, but only 39% of patients with monoclonal gammopathy of undetermined significance (MGUS) expressed CD47; median expression level increased 10-fold with progression from MGUS to MM. Elevated TSP1/TSP2 levels occurred in bone marrow cultures from MM patients compared with healthy donors. CD47 and TSP1/TSP2 may have a potential role in the pathophysiology of MM, probably in the interaction between MM PCs and the microenvironment.
Yang S, Shin J, Park KH, et al.Molecular basis of the differences between normal and tumor tissues of gastric cancer.
Biochim Biophys Acta. 2007; 1772(9):1033-40 [PubMed
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To be able to describe the differences between the normal and tumor tissues of gastric cancer at a molecular level would be essential in the study of the disease. We investigated the gene expression pattern in the two types of tissues from gastric cancer by performing expression profiling of 86 tissues on 17K complementary DNA microarrays. To select for the differentially expressed genes, class prediction algorithm was employed. For predictor selection, samples were first divided into a training (n=58), and a test set (n=28). A group of 894 genes was selected by a t-test in a training set, which was used for cross-validation in the training set and class (normal or tumor) prediction in the test set. Smaller groups of 894 genes were individually tested for their ability to correctly predict the normal or tumor samples based on gene expression pattern. The expression ratios of the 5 genes chosen from microarray data can be validated by real time RT-PCR over 6 tissue samples, resulting in a high level of correlation, individually or combined. When a representative predictor set of 92 genes was examined, pathways of 'focal adhesion' (with gene components of THBS2, PDGFD, MAPK1, COL1A2, COL6A3), 'ECM-receptor interaction' pathway (THBS2, COL1A2, COL6A3, FN1) and 'TGF-beta signaling' (THBS2, MAPK1, INHBA) represent some of the main differences between normal and tumor of gastric cancer at a molecular level.
Park BL, Kim YJ, Cheong HS, et al.Association of common promoter polymorphisms of MCP1 with hepatitis B virus clearance.
Exp Mol Med. 2006; 38(6):694-702 [PubMed
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Hepatocellular carcinoma (HCC) is one of the most common malignant cancers closely associated with chronic infection by the hepatitis B virus (HBV) or the hepatitis C virus (HCV) throughout the world. In this study, the genetic associations of 20 known polymorphisms in eight candidate genes, including angiotensinogen (AGT), cadherin 1 (CDH1), cyclooxygenase 2 (COX2), monocyte chemotactic protein-1 (MCP1), multidrug resistance 1 (MDR1), chemokine ligand 5 (RANTES), thrombospondin 2 (THBS2), and thrombospondin 4 (THBS4), were analyzed in a large chronic hepatitis B cohort (n=1,095) recruited from the Korean population. In addition, three polymorphisms in chemokine receptor 4 (CXCR4) and vimentin (VIM) identified in this study were also genotyped. Using logistic regression analysis controlling possible confounding factors, one common (freq.=0.367) promoter polymorphism of MCP1 (MCP1-2518G>A) among analyzed polymorphisms was significantly associated with clearance of HBV infection. The frequency of homozygotes for the MCP1-2518A allele (MCP1-2518A/A) among chronic hepatitis B virus (HBV) carrier patients was significantly higher than that among spontaneously recovered (SR) subjects (17.7% vs. 10.4%)(OR=1.78, P=0.004). Our findings imply a plausible explanation for the contribution of host genetic determinants to the variable outcome of HBV infection, which might provide valuable information for future genetic study in this area.
Cavalli LR, Urban CA, Dai D, et al.Genetic and epigenetic alterations in sentinel lymph nodes metastatic lesions compared to their corresponding primary breast tumors.
Cancer Genet Cytogenet. 2003; 146(1):33-40 [PubMed
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The accumulation of genetic and epigenetic changes plays a pivotal role in tumor development and progression. In this study, we investigated these changes using comparative genomic hybridization and bisulfite polymerase chain reaction analysis for CpG island hypermethylation of the following genes: TP16, THBS2, E-Cadherin (ECAD), RARbeta2, MINT1, MINT2, and MINT31 in six paired primary breast tumors and their matched sentinel lymph nodes (SLN). The most frequent chromosomal alterations observed were the following: losses of 6q13 approximately q23 and 13q13 approximately q32 and gains of 9q31 approximately qter, 11p15 approximately q21, 12q23 approximately qter, and 20q12 approximately qter. Gain of 6p21 approximately pter was observed in the SLN but in none of the primary tumors. Overall, 71% (30/42) of the methylation measurements were identical between the primary tumors and the SLN. Of the six cases, two showed no differences between the primary tumors and SLN, one tumor with 4 of 7 genes hypermethylated in the primary tumor showed loss of all four hypermethylation events in the SLN, and the remaining three tumors showed loss of one methylation event and simultaneous gain of one to two methylation changes in the SLN. This is the first study reporting genetic and epigenetic alterations in breast sentinel lymph nodes compared to their corresponding primary tumors. Characterization of such alterations may lead to identification of initial events associated with the metastatic dissemination process.
Whitcomb BP, Mutch DG, Herzog TJ, et al.Frequent HOXA11 and THBS2 promoter methylation, and a methylator phenotype in endometrial adenocarcinoma.
Clin Cancer Res. 2003; 9(6):2277-87 [PubMed
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PURPOSE: This study was designed to determine whether there is a methylator phenotype in stage I and II endometrioid endometrial adenocarcinoma, and if so, whether methylation correlates with recurrence.
EXPERIMENTAL DESIGN: Bisulfite-converted DNAs from 24 stage I and II primary cancers (12 recurrent and 12 nonrecurrent), and 5 endometrial cancer cell lines were analyzed for methylation in the promoter regions of seven genes. A methylation index (MeI) was calculated for each tumor. Frequent HOXA11 and THBS2 methylation prompted analysis of case-matched bloods and 25 additional nonrecurrent primary cancers. Statistical analysis included Fisher's exact and Student t tests.
RESULTS: Rates of methylation in the initial tumor series were as follows: HOXA11, 70.8%; THBS2, 62.5%; MLH1, 33.3%; CTNNB1, 16.7%; VDR, 4.2%; CDKN2A, 4.2%; and THBS1, 0%. There was no difference in the MeI of recurrent and nonrecurrent cases. However, cell lines had higher mean MeI. High rates of HOXA11 and THBS2 methylation were confirmed in the additional nonrecurrent tumors. None of the 24 case-matched bloods had HOXA11 methylation, whereas three blood DNAs showed THBS2 methylation. There was a statistically significant difference in the rate of HOXA11 methylation in recurrent and nonrecurrent tumors (P = 0.0167).
CONCLUSIONS: Endometrial adenocarcinomas have a methylator phenotype. No correlation between MeI and clinicopathologic variables in early stage tumors was observed. High rates of methylation were found in the HOXA11 and THBS2 promoter regions. HOXA11 promoter methylation was significantly more frequent in recurrent than nonrecurrent cases. HOXA11 methylation in early stage endometrial cancer is associated with poor outcome.
Kamochi J, Tokunaga T, Tomii Y, et al.Overexpression of the thrombospondin 2 (TSP2) gene modulated by the matrix metalloproteinase family expression and production in human colon carcinoma cell line.
Oncol Rep. 2003 Jul-Aug; 10(4):881-4 [PubMed
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Thrombospondin 2 (TSP2) is an extracellular matrix glycoprotein involved in tumor progression and angiogenesis. We evaluated whether overexpression of the TSP2 gene show an alteration of various genes by cDNA arrays in the colon carcinoma cell line SW480. The transformants with the human TSP2 gene overexpression showed a down-regulation of matrix metalloproteinase 2 (MMP2) and MMP9 in comparison to those with vector-control. Protein production of MMP2 and MMP9 decreased in the transformants overexpressing the TSP2 gene. Conversely, the SW480 transformants showed up-regulation of MMP12 and MMP17. These results suggested that the TSP2 gene is a multifunctional modulator of remodeling tissue in which matrix degradation is required.
Garcia-Manero G, Daniel J, Smith TL, et al.DNA methylation of multiple promoter-associated CpG islands in adult acute lymphocytic leukemia.
Clin Cancer Res. 2002; 8(7):2217-24 [PubMed
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PURPOSE: Aberrant methylation of promoter-associated CpG islands is an epigenetic oncogenic mechanism. The objective of this study was to define the methylation characteristics of patients with acute lymphocytic leukemia (ALL).
EXPERIMENTAL DESIGN: Using bisulfite-PCR followed by restriction enzyme digestion (COBRA), we have analyzed the methylation status of 10 promoter-associated CpG islands in 80 untreated adult patients with ALL.
RESULTS: Mean methylation density of MDR1, THBS2, MYF3, ER, p15, THBS1, CD10, C-ABL, and p16 was 24.5%, 20.8%, 17.6%, 16.1%, 11.3%, 8.9%, 4.5%, 3.7%, and 1.3% respectively. p73 was methylated in 17 of 80 cases (21.2%). A total of 86.2% of the cases had methylation of at least one gene, and 42.5% of the cases had methylation of three or more genes. MDR1 methylation was inversely correlated with age (P = 0.01). CD10 methylation inversely correlated with CD10 expression (P = 0.0001). Methylation of MDR1 and THBS1 was inversely associated with the presence of the Philadelphia chromosome, whereas C-ABL methylation correlated with the presence of the p210 variant of the Philadelphia chromosome. In univariate analysis, methylation of THBS1 was associated with a favorable outcome (P = 0.02), whereas methylation of p73, p15, and C-ABL was associated with a trend toward worse prognosis.
CONCLUSIONS: Aberrant DNA methylation of promoter-associated CpG islands is very common in adult ALL and potentially defines subgroups with distinct clinical and biological characteristics.