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2.
J Neurooncol ; 119(1): 59-70, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24797829

ABSTRACT

In the present study, we searched for genes highly expressed in placenta and that could contribute to the establishment and maintenance of a malignant phenotype in different types of tumours, and in astrocytomas in particular. We employed a strategy based on the integration of in silico data from previously generated massively parallel signature sequencing and public serial analysis of gene expression databases. Among 12 selected genes, CD99 exhibited the highest relative mRNA expression in GBM compared to non-neoplastic brain tissues. In a larger cohort of astrocytic tumours, we further demonstrated increased CD99 expression in all malignant grades, with GBMs showing the highest values. These findings were confirmed at the protein level by Western blotting and immunohistochemistry. Additionally, we demonstrated the CD99 localisation profile in astrocytic tumours. Interestingly, CD99 expression was confined to the cytoplasm or membrane in more malignant astrocytomas, in contrast to non-neoplastic brain tissue or non-infiltrative pilocytic astrocytoma, which showed no obvious staining in these structures. Comparison of three GBM cell lines revealed higher CD99 expression at the membrane and higher migratory capacity in the A172 and U87MG lines, but lower CD99 expression and no migratory ability in the T98 line. Knocking down CD99 expression by siRNA decreased significantly the migration of both cell lines. These integrated CD99 gene and protein expression results suggest that CD99 expression in astrocytomas of different malignant grades might contribute to the infiltrative ability and support the importance of CD99 as a potential target to reduce infiltrative astrocytoma capacity in migration and invasion.


Subject(s)
Antigens, CD/metabolism , Astrocytoma/metabolism , Brain Neoplasms/metabolism , Brain/metabolism , Cell Adhesion Molecules/metabolism , Cell Movement/genetics , Placenta/metabolism , Up-Regulation , 12E7 Antigen , Antigens, CD/genetics , Astrocytoma/genetics , Astrocytoma/pathology , Brain/pathology , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Adhesion Molecules/genetics , Cell Line, Tumor , Female , Gene Expression Regulation, Neoplastic , Humans , Neoplasm Grading , Pregnancy
3.
J Orthop Sci ; 16(4): 458-66, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21691740

ABSTRACT

BACKGROUND: Osteosarcoma (OS) is the most frequent bone tumor in children and adolescents. Tumor antigens are encoded by genes that are expressed in many types of solid tumors but are silent in normal tissues, with the exception of placenta and male germ-line cells. It has been proposed that antigen tumors are potential tumor markers. OBJECTIVES: The premise of this study is that the identification of novel OS-associated transcripts will lead to a better understanding of the events involved in OS pathogenesis and biology. METHODS: We analyzed the expression of a panel of seven tumor antigens in OS samples to identify possible tumor markers. After selecting the tumor antigen expressed in most samples of the panel, gene expression profiling was used to identify osteosarcoma-associated molecular alterations. A microarray was employed because of its ability to accurately produce comprehensive expression profiles. RESULTS: PRAME was identified as the tumor antigen expressed in most OS samples; it was detected in 68% of the cases. Microarray results showed differences in expression for genes functioning in cell signaling and adhesion as well as extracellular matrix-related genes, implying that such tumors could indeed differ in regard to distinct patterns of tumorigenesis. CONCLUSIONS: The hypothesis inferred in this study was gathered mostly from available data concerning other kinds of tumors. There is circumstantial evidence that PRAME expression might be related to distinct patterns of tumorigenesis. Further investigation is needed to validate the differential expression of genes belonging to tumorigenesis-related pathways in PRAME-positive and PRAME-negative tumors.


Subject(s)
Antigens, Neoplasm/genetics , Bone Neoplasms/genetics , Gene Expression Profiling , Osteosarcoma/genetics , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Young Adult
4.
Nucleic Acids Res ; 39(14): 6056-68, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21493686

ABSTRACT

Although patterns of somatic alterations have been reported for tumor genomes, little is known on how they compare with alterations present in non-tumor genomes. A comparison of the two would be crucial to better characterize the genetic alterations driving tumorigenesis. We sequenced the genomes of a lymphoblastoid (HCC1954BL) and a breast tumor (HCC1954) cell line derived from the same patient and compared the somatic alterations present in both. The lymphoblastoid genome presents a comparable number and similar spectrum of nucleotide substitutions to that found in the tumor genome. However, a significant difference in the ratio of non-synonymous to synonymous substitutions was observed between both genomes (P = 0.031). Protein-protein interaction analysis revealed that mutations in the tumor genome preferentially affect hub-genes (P = 0.0017) and are co-selected to present synergistic functions (P < 0.0001). KEGG analysis showed that in the tumor genome most mutated genes were organized into signaling pathways related to tumorigenesis. No such organization or synergy was observed in the lymphoblastoid genome. Our results indicate that endogenous mutagens and replication errors can generate the overall number of mutations required to drive tumorigenesis and that it is the combination rather than the frequency of mutations that is crucial to complete tumorigenic transformation.


Subject(s)
Breast Neoplasms/genetics , Genetic Variation , Genome, Human , Cell Line, Transformed , Cell Line, Tumor , Chromosome Aberrations , Female , Humans , Lymphocytes , Middle Aged , Mutation , Point Mutation , Protein Interaction Mapping , Sequence Analysis, DNA
5.
Genomics ; 94(3): 153-60, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19540335

ABSTRACT

Cancer/testis Antigens (CTAs) are immunogenic proteins with a restricted expression pattern in normal tissues and aberrant expression in different types of tumors being considered promising candidates for immunotherapy. We used the alignment between EST sequences and the human genome sequence to identify novel CT genes. By examining the EST tissue composition of known CT clusters we defined parameters for the selection of 1184 EST clusters corresponding to putative CT genes. The expression pattern of 70 CT gene candidates was evaluated by RT-PCR in 21 normal tissues, 17 tumor cell lines and 160 primary tumors. We were able to identify 4 CT genes expressed in different types of tumors. The presence of antibodies against the protein encoded by 1 of these 4 CT genes (FAM46D) was exclusively detected in plasma samples from cancer patients. Due to its restricted expression pattern and immunogenicity FAM46D represents a novel target for cancer immunotherapy.


Subject(s)
Antigens, Neoplasm/immunology , Expressed Sequence Tags , Neoplasm Proteins/immunology , Neoplasms/blood , Antigens, Neoplasm/genetics , Case-Control Studies , Databases, Nucleic Acid , Genome, Human , Humans , Male , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Neoplasms/pathology , Nucleotidyltransferases , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Testis/immunology , Tumor Cells, Cultured
6.
Exp Hematol ; 37(4): 446-9, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19211183

ABSTRACT

OBJECTIVE: This study aims to analyze the expression of cancer testis antigen 45 (CT45) in normal tissues and in plasma cell disorders and to identify possible associations with clinical data and prognosis in multiple myeloma (MM) patients. MATERIALS AND METHODS: Expression of CT45 was studied in 20 normal tissues (testis, placenta, skeletal muscle, bladder, lung, spleen, heart, brain and fetal brain, thymus, uterus, stomach, mammary gland, pancreas, prostate, small intestine, kidney, adrenal gland, spinal cord, colon, and one pool of 10 normal bone marrow samples) and bone marrow aspirates from 3 monoclonal gammopathies of undetermined significance, 5 solitary plasmacytomas, 61 newly diagnosed MM patients and MM cell line U266 by reverse transcriptase polymerase chain reaction. RESULTS: CT45 was positive in 3 of 20 (15%) normal tissues tested: lung, brain (both fetal and adult), and spinal cord. Among monoclonal gammopathies, CT45 was positive in 2 of 5 (40%) solitary plasmacytomas bone marrow aspirates, 10 of 61 (16%) MM bone marrow aspirates, and in the U266 MM cell line. CONCLUSIONS: We did not find associations between bone marrow histology and CT45 expression. However, we demonstrated for the first time that positive expression of CT45 was associated with poor prognostic (International Staging System) and poor outcomes in MM patients, meaning that CT45-positive cases presented seven times more chance of worse evolution than the negative ones.


Subject(s)
Antigens, Neoplasm/blood , Antigens, Neoplasm/metabolism , Bone Marrow/metabolism , Gene Expression Regulation, Neoplastic , Multiple Myeloma/physiopathology , Aged , Disease Progression , Female , Humans , Male , Middle Aged , Multiple Myeloma/diagnosis , Multiple Myeloma/metabolism , Predictive Value of Tests , Prognosis , Reference Standards , Reverse Transcriptase Polymerase Chain Reaction
7.
Cancer Lett ; 278(1): 41-8, 2009 Jun 08.
Article in English | MEDLINE | ID: mdl-19171422

ABSTRACT

Serial analysis of gene expression (SAGE) allows a comprehensive profiling of gene expression within a given tissue and also an assessment of transcript abundance. We generated SAGE libraries from normal and neoplastic plasma cells to identify genes differentially expressed in multiple myeloma (MM). Normal plasma cells were obtained from palatine tonsils and MM SAGE library was generated from bone marrow plasma cells of MM patients. We obtained 29,918 SAGE tags from normal and 10,340 tags from tumor libraries. Computer-generated genomic analysis identified 46 upregulated genes in the MM library. Ten upregulated genes were selected for further investigation. Differential expression was validated by quantitative real-time PCR in purified plasma cells of 31 patients and three controls. P53CSV, DDX5, MAPKAPK2 and RANBP2 were found to be upregulated in at least 50% of the MM cases tested. All of them were also found upregulated in MM when compared to normal plasma cells in a meta-analysis using ONCOMINE microarray database. Antibodies specific to DDX5, RANBP2 and MAPKAPK2 were used in a TMA containing 57 MM cases and confirmed the expression of these proteins in 74%, 96%, and 21% of the MM samples, respectively. Analysis of differential expression using SAGE could identify genes important for myeloma tumorigenesis (P53CSV, DDX5, MAPKPK2 and RANBP2) and that could potentially be useful as therapeutic targets.


Subject(s)
DEAD-box RNA Helicases/genetics , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Intracellular Signaling Peptides and Proteins/genetics , Molecular Chaperones/genetics , Multiple Myeloma/genetics , Nuclear Pore Complex Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Bone Marrow Transplantation , DNA Primers , Female , Humans , Male , Meta-Analysis as Topic , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/pathology , Multiple Myeloma/surgery , Neoplasm Staging , Oligonucleotide Array Sequence Analysis , Polymerase Chain Reaction , Syndecan-1/analysis , Transcription, Genetic , Tumor Suppressor Protein p53/genetics , Up-Regulation
8.
Nucleic Acids Res ; 37(Database issue): D816-9, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18838390

ABSTRACT

The potency of the immune response has still to be harnessed effectively to combat human cancers. However, the discovery of T-cell targets in melanomas and other tumors has raised the possibility that cancer vaccines can be used to induce a therapeutically effective immune response against cancer. The targets, cancer-testis (CT) antigens, are immunogenic proteins preferentially expressed in normal gametogenic tissues and different histological types of tumors. Therapeutic cancer vaccines directed against CT antigens are currently in late-stage clinical trials testing whether they can delay or prevent recurrence of lung cancer and melanoma following surgical removal of primary tumors. CT antigens constitute a large, but ill-defined, family of proteins that exhibit a remarkably restricted expression. Currently, there is a considerable amount of information about these proteins, but the data are scattered through the literature and in several bioinformatic databases. The database presented here, CTdatabase (http://www.cta.lncc.br), unifies this knowledge to facilitate both the mining of the existing deluge of data, and the identification of proteins alleged to be CT antigens, but that do not have their characteristic restricted expression pattern. CTdatabase is more than a repository of CT antigen data, since all the available information was carefully curated and annotated with most data being specifically processed for CT antigens and stored locally. Starting from a compilation of known CT antigens, CTdatabase provides basic information including gene names and aliases, RefSeq accession numbers, genomic location, known splicing variants, gene duplications and additional family members. Gene expression at the mRNA level in normal and tumor tissues has been collated from publicly available data obtained by several different technologies. Manually curated data related to mRNA and protein expression, and antigen-specific immune responses in cancer patients are also available, together with links to PubMed for relevant CT antigen articles.


Subject(s)
Antigens, Neoplasm/metabolism , Databases, Protein , Neoplasm Proteins/metabolism , Testis/metabolism , Antigens, Neoplasm/genetics , Antigens, Neoplasm/immunology , Expressed Sequence Tags , Humans , Immunity , Male , Neoplasm Proteins/genetics , Neoplasm Proteins/immunology , Polymerase Chain Reaction , PubMed , RNA, Messenger/metabolism
9.
Acta Trop ; 108(2-3): 263-6, 2008.
Article in English | MEDLINE | ID: mdl-18834847

ABSTRACT

In the 1990s, WHO/TDR created a product development program and initiated collaborations with other major international donors to promote rapid vaccine development and other tools for the control of endemic diseases. This "push strategy" was chosen to achieve effective research projects fostering innovation in the context of rapid product development. In the field of vaccine development, the aim was to bring forth ways and means to immunize against the most important human parasite diseases. Although the malaria vaccine projects scored initial successes it has been difficult to move forward decidedly. With regard to schistosomiasis, more than 10 important antigens with strong potential as vaccines candidates emerged from the several 100 scientific projects supported by international donor agencies and national research programs over the last few decades. Among those still seriously pursued, the Fatty Acid-Binding Protein (FABP)-14 kDa Schistosoma mansoni (Sm14) antigen stands out, both due to its steady progress towards field trials and because it represents the sole vaccine candidate to emerge from an endemic country. Work has now progressed to the scale-up level and an industrial production process has successfully been put in place. The very special feature of Sm14 is its strong immunological reactivity with an antigen shared between two different important parasites, which give this vaccine candidate the potential to be used against more than one infection. It has been demonstrated that it has effect not only against S. mansoni in humans but also against Fasciola hepatica, a parasite that causes disease in cattle and sheep leading to annual losses over 3 $US billion to the food industry worldwide. The Sm14 patents, granted to Oswaldo Cruz Foundation (FIOCRUZ), a Brazilian scientific institution directly linked to the Brazilian Ministry of Health, have been licensed to a private company which has the intention to lead the Sm14 project to success, both in the veterinary and in the human field. The objective is to provide economic performance by fostering scientific and economic progress and thus reach the global market. Sm14 is at present at the stage of planning clinical trials under a private-public partnership (PPP) initiative in collaboration with FIOCRUZ which has recently received significant financial support from FINEP, a public Brazilian Financial Agency.


Subject(s)
Antigens, Helminth/immunology , Fascioliasis/veterinary , Fatty Acid Transport Proteins/immunology , Helminth Proteins/immunology , Schistosomiasis mansoni/prevention & control , Vaccines/immunology , Animals , Cattle , Cattle Diseases/prevention & control , Fasciola hepatica/immunology , Fascioliasis/prevention & control , Humans , Schistosoma mansoni/immunology , Sheep , Sheep Diseases/prevention & control
10.
Cancer Immun ; 8: 7, 2008 Apr 22.
Article in English | MEDLINE | ID: mdl-18426187

ABSTRACT

Medulloblastoma is the most common childhood malignant tumor of the central nervous system. Treatment of medulloblastoma requires harmful therapy and nevertheless carries a poor prognosis. Due to their presence in various cancers and their limited expression in normal tissues, CT antigens are ideal vaccine targets for tumor immunotherapy. CT antigens, such as MAGE and NY-ESO-1, have been employed in clinical trials in various malignancies but little is known about their presence in medulloblastoma. We analyzed 25 medulloblastomas for the expression of a panel of CT antigens by RT-PCR and immunohistochemistry. Messenger RNA expression in the samples was as follows: GAGE 64%, MAGEA3/6 56%, SYCP1 44%, SLCO6A1 32%, MAGEC1 28%, MAGEC2 28%, MAGEA4 28%, NY-ESO-1 20%, MAGEA1 16%, and TPTE 0%. All cases except one (96%) were positive for mRNA expression of at least one CT gene. However, CT antigen expression was scarce on a protein level. Immunoreaction to monoclonal antibody E978 (NY-ESO-1) was negative in all cases; MA454 (MAGEA1), 57B (MAGEA4), M3H67 (MAGEA3/6), CT10#5 (MAGEC2) and #23 (GAGE) were each positive in 1 case, while the highest incidence of positive immunostaining, albeit heterogeneous, was seen with CT7-33 (MAGEC1) in 3 out of the 25 cases. The absence of correlation between mRNA and protein expression in medulloblastoma has not been observed in other tumors and further studies addressing the biology of CT antigens are necessary to investigate the present discrepant results.


Subject(s)
Antigens, Neoplasm/biosynthesis , Cerebellar Neoplasms/immunology , Medulloblastoma/immunology , Adult , Antigens, Neoplasm/analysis , Antigens, Neoplasm/genetics , Cancer Vaccines , Cerebellar Neoplasms/genetics , Cerebellar Neoplasms/pathology , Child , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Medulloblastoma/genetics , Medulloblastoma/pathology , Membrane Proteins/biosynthesis , Membrane Proteins/genetics , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , RNA Processing, Post-Transcriptional/genetics , RNA, Messenger/metabolism , Testis/metabolism , Testis/pathology
11.
Int J Cancer ; 122(4): 807-15, 2008 Feb 15.
Article in English | MEDLINE | ID: mdl-17960622

ABSTRACT

We have performed cDNA microarray analyses to identify gene expression differences between highly invasive glioblastoma multiforme (GBM) and typically benign pilocytic astrocytomas (PA). Despite the significant clinical and pathological differences between the 2 tumor types, only 63 genes were found to exhibit 2-fold or greater overexpression in GBM as compared to PA. Forty percent of these genes are related to the regulation of the cell cycle and mitosis. QT-PCR validation of 6 overexpressed genes: MELK, AUKB, ASPM, PRC1, IL13RA2 and KIAA0101 confirmed at least a 5-fold increase in the average expression levels in GBM. Maternal embryonic leucine zipper kinase (MELK) exhibited the most statistically significant difference. A more detailed investigation of MELK expression was undertaken to study its oncogenic relevance. In the examination of more than 100 tumors of the central nervous system, we found progressively higher expression of MELK with astrocytoma grade and a noteworthy uniformity of high level expression in GBM. Similar level of overexpression was also observed in medulloblastoma. We found neither gene promoter hypomethylation nor amplification to be a factor in MELK expression, but were able to demonstrate that MELK knockdown in malignant astrocytoma cell lines caused a reduction in proliferation and anchorage-independent growth in in vitro assays. Our results indicate that GBM and PA differ by the expression of surprisingly few genes. Among them, MELK correlated with malignancy grade in astrocytomas and represents a therapeutic target for the management of the most frequent brain tumors in adult and children.


Subject(s)
Astrocytoma/genetics , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Protein Serine-Threonine Kinases/genetics , Adult , Apoptosis , Astrocytoma/pathology , Brain/metabolism , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Proliferation , Child , DNA Methylation , Gene Dosage , Glioblastoma/pathology , Humans , Oligonucleotide Array Sequence Analysis , Promoter Regions, Genetic , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , RNA, Small Interfering/pharmacology , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured
12.
Proc Natl Acad Sci U S A ; 103(48): 18066-71, 2006 Nov 28.
Article in English | MEDLINE | ID: mdl-17114284

ABSTRACT

Cancer/testis (CT) antigens are immunogenic proteins expressed in normal gametogenic tissues and in different types of tumors. CT antigens are promising candidates for cancer immunotherapy, and the identification of novel CT antigens is a prerequisite for the development of cancer vaccines. We have identified a CT antigen, named CTSP-1, with partial similarity to the breast differentiation antigen NY-BR-1. CTSP-1 presents several splicing and polyadenylation variants and has a very restricted expression pattern among normal tissues. CTSP-1 is exclusively expressed in normal testis and is aberrantly expressed in 47.6% (10 of 21) of tumor cell lines and in 44.4% (75 of 169) of tumors from different histological types. The highest percentages of positive expression were observed in melanomas (59.0%) followed by prostate (58.0%) and lung (57.0%) tumors. CTSP-1 is part of a highly conserved gene family, and members of this family also have a restricted expression pattern and similar protein structure. Antibodies against members of this gene family were detected in 10% (14 of 141) of plasma samples from patients with a wide spectrum of tumors. The highest percentages of antibody response were observed in patients with prostate (20.8%), thyroid (20.0%), and breast (16.6%) tumors. Because of its very restricted expression pattern in normal tissues and immunogenicity in different types of tumors, CTSP-1 should be considered a promising candidate for cancer immunotherapy.


Subject(s)
Antigens, Neoplasm/genetics , Antigens, Neoplasm/immunology , Neoplasms/genetics , Neoplasms/immunology , Nuclear Proteins/genetics , Nuclear Proteins/immunology , Alternative Splicing/genetics , Animals , Antigens, Neoplasm/classification , Antigens, Neoplasm/metabolism , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Genetic Variation/genetics , Humans , Male , Mice , Molecular Sequence Data , Neoplasms/classification , Neoplasms/metabolism , Nuclear Proteins/classification , Nuclear Proteins/metabolism , Polyadenylation , RNA, Messenger/genetics , RNA, Messenger/metabolism
13.
Genet Mol Res ; 5(2): 315-22, 2006 Jun 30.
Article in English | MEDLINE | ID: mdl-16819711

ABSTRACT

The methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is associated with the expression of a thermolabile enzyme with decreased activity that influences the pool of methyl-donor molecules. Several studies have reported an association between C677T polymorphism and susceptibility to colorectal cancer (CRC). Considering that methylation abnormalities appear to be important for the pathogenesis of CRC, we examined the correlation between the genotype of the MTHFR C677T polymorphism, hypermethylation of the promoter region of five relevant genes (DAPK, MGMT, hMLH1, p16(INK4a), and p14(ARF)), and microsatellite instability, in 106 patients with primary CRCs in Brazil. We did not find significant differences in the genotypic frequencies of the MTHFR C677T polymorphism when one or more loci were hypermethylated. However, we did find a significant excess of 677TT individuals among patients with CRC who had microsatellite instability. This strong association was independent of the methylation status of hMLH1 and of the biogeographical genomic ancestry of the patients. Although the mechanism responsible for the link between the C677T polymorphism and microsatellite instability was not apparent, this finding may provide a clue towards a better understanding of the pathogenesis of microsatellite instability in human colorectal cancer.


Subject(s)
Biomarkers, Tumor/genetics , Colorectal Neoplasms/genetics , DNA Methylation , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Genetic/genetics , Case-Control Studies , Colorectal Neoplasms/enzymology , Female , Genetic Predisposition to Disease , Genomic Instability/genetics , Genotype , Humans , Male , Microsatellite Repeats/genetics , Promoter Regions, Genetic/genetics
14.
Leuk Res ; 30(11): 1333-9, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16620968

ABSTRACT

The preferentially expressed antigen in melanoma (PRAME) gene is aberrantly expressed in chronic lymphoproliferative disorders (CLD). We produced and characterized an anti-PRAME monoclonal antibody (MoAb), which was then applied in a quantitative flow cytometric (QFC) method to evaluate PRAME expression in leukemic cells from the peripheral blood (PB) of 47 patients with chronic lymphocytic leukemia and seven with mantle cell lymphoma as well as in the PB mononuclear cells (PBMCs) and B lymphocytes from 15 healthy subjects. Approximately 90% of CLD, but none of the normal samples, presented more than 20% of PRAME+ lymphocytes. Moreover, the intensity of PRAME expression was significantly higher in CLD cells compared to normal B lymphocytes and PBMCs. By immunofluorescence microscopy and by permeabilized flow cytometry we demonstrated that PRAME is a membrane antigen and a cytoplasmic protein aberrantly expressed in malignant CLD. Our results suggest that the analysis of PRAME protein may contribute for the distinction between normal and leukemic cells in CLD, and that PRAME may be a potential target for therapy.


Subject(s)
Antigens, Neoplasm/biosynthesis , Antigens, Neoplasm/genetics , Gene Expression Profiling , Gene Expression Regulation, Leukemic , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Lymphoma, Mantle-Cell/genetics , Lymphoproliferative Disorders/genetics , Antibodies, Monoclonal/immunology , Antibody Specificity , Antigen-Antibody Reactions , Antigens, Neoplasm/immunology , Cell Line, Tumor , Flow Cytometry/methods , Fluorescent Antibody Technique/methods , Humans , In Situ Hybridization, Fluorescence/methods , Reverse Transcriptase Polymerase Chain Reaction/methods
15.
Oncol Rep ; 13(2): 325-8, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15643519

ABSTRACT

Cancers often exhibit aberrant methylation of gene promoter regions associated with loss of tumor suppressor and/or DNA repair gene function. Such methylation constitutes an excellent marker for the molecular detection of micro-metastases and the diagnosis of tumor recurrences. We have developed a multiplex methylation-specific PCR (MSP) procedure for rapid and simultaneous assessment of the methylation of 5 loci: the tumor suppressor genes p16INK4a, death-associated protein kinase (DAPK) and p14ARF, and the DNA repair genes hMLH1 and O6-methylguanine-DNA-methyltransferase (MGMT). This multiplex test uses one single PCR reaction and only one electrophoretic run. In 98 samples of colorectal cancer studied, methylation of MGMT, DAPK, p16, hMLH1 and p14 was present in 31, 20, 17, 16 and 14% of tumors, respectively. In 58% of the tumors at least one methylated gene was found. This multiplex MSP constitutes a simple and inexpensive method for screening of molecular signatures in colorectal cancer and can be used profitably before employing more expensive and complex techniques such as microarray testing.


Subject(s)
Colorectal Neoplasms/diagnosis , DNA Methylation , Polymerase Chain Reaction/methods , Adaptor Proteins, Signal Transducing , Apoptosis Regulatory Proteins , Calcium-Calmodulin-Dependent Protein Kinases/genetics , Carrier Proteins , Colorectal Neoplasms/genetics , Death-Associated Protein Kinases , Genes, p16 , Humans , MutL Protein Homolog 1 , Neoplasm Proteins/genetics , Nuclear Proteins , Sensitivity and Specificity
16.
Genet Mol Res ; 3(3): 395-409, 2004 Sep 30.
Article in English | MEDLINE | ID: mdl-15614730

ABSTRACT

Levels of mtDNA(4977) deletions (DeltamtDNA(4977)) have been found to be lower in tumors than in adjacent non-tumoral tissues. In 87 cancer patients, DeltamtDNA(4977) was detected by multiplex polymerase chain reaction (PCR) amplification in 43 (49%) of the tumors and in 74 (85%) of the samples of non-tumoral tissues that were adjacent to the tumors. DeltamtDNA(4977) deletions were detected in 24% of the breast tumors, 52% of the colorectal tumors, 79% of the gastric tumors, and 40% of the head and neck tumors as compared with 77, 83, 100, and 90% of the adjacent respective non-tumoral tissues at the same DNA template dilution. Based on limiting dilution PCR of 16 tumors and their adjacent non-tumoral tissues, it was found that the amount of DeltamtDNA(4977) was 10- to 100-fold lower in the tumor than in the respective control non-tumoral tissues. Real-time PCR experiments were performed to quantify the number of DeltamtDNA(4977) deletions per cell, by determining the mitochondrial-to-nuclear DNA ratio. In all of the cases of breast, colorectal, gastric, and head and neck cancer the proportion of DeltamtDNA(4977) in tumors was lower than that of the respective non-tumoral tissue. Traces of DeltamtDNA(4977) in tumors were apparently due to contamination of tumor tissue with surrounding non-tumoral tissue, as evidenced by tumor microdissection and in situ PCR techniques, suggesting that tumors are essentially free of this mutation. Although the metabolic effect of DeltamtDNA(4977) may be minimal in normal (non-tumor) tissue, in tissue under stress, such as in tumors, even low levels of DeltamtDNA(4977) deletions may be intolerable.


Subject(s)
Breast Neoplasms/genetics , Colorectal Neoplasms/genetics , Head and Neck Neoplasms/genetics , Mutation/genetics , Sequence Deletion/genetics , Stomach Neoplasms/genetics , Case-Control Studies , DNA, Mitochondrial/genetics , Female , Humans , Polymerase Chain Reaction , Tumor Cells, Cultured
17.
Leuk Res ; 28(12): 1281-6, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15475069

ABSTRACT

Cancer patients receiving chemotherapy are exposed to high doses of cytotoxic and genotoxic drugs which, in some cases, can lead to treatment related leukemia. Since this only occurs in a minority of patients, however, it is possible some individuals are predisposed due to genetic polymorphisms in genes for enzymes that mediate drug metabolism. To address this possibility we measured the genotoxicity of chemotherapeutic agents in patients receiving treatment for ALL by the frequency of the Vgamma/Jbeta trans-rearrangement in their peripheral blood leukocytes and compared this with CYP3A4 genotype. CYP3A4 is the most abundant of the cytochrome P450 (CYP) enzyme in the liver and intestine which contains a common -392A>G substitution in the promoter region (CYP3A4*1B allele). We found a significant increase in the frequency of rearrangements during chemotherapy only in patients homozygous for the wild type CYP3A4*1A allele. This provides a direct link between CYP3A4 genotype and susceptibility to drug genotoxicity thus strengthening the possibility that predisposition to treatment related leukemia may be measurable by simple genetic testing.


Subject(s)
Cytochrome P-450 Enzyme System/genetics , Drug-Related Side Effects and Adverse Reactions/genetics , Immunoglobulin Variable Region/genetics , Leukocytes , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Antineoplastic Agents/toxicity , Cytochrome P-450 CYP3A , Gene Rearrangement , Genotype , Humans , Neoplasms, Second Primary/chemically induced , Neoplasms, Second Primary/etiology , Neoplasms, Second Primary/genetics , Polymorphism, Genetic , Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy
18.
Mol Plant Microbe Interact ; 17(8): 827-36, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15305603

ABSTRACT

The genome sequence of Leifsonia xyli subsp. xyli, which causes ratoon stunting disease and affects sugarcane worldwide, was determined. The single circular chromosome of Leifsonia xyli subsp. xyli CTCB07 was 2.6 Mb in length with a GC content of 68% and 2,044 predicted open reading frames. The analysis also revealed 307 predicted pseudogenes, which is more than any bacterial plant pathogen sequenced to date. Many of these pseudogenes, if functional, would likely be involved in the degradation of plant heteropolysaccharides, uptake of free sugars, and synthesis of amino acids. Although L. xyli subsp. xyli has only been identified colonizing the xylem vessels of sugarcane, the numbers of predicted regulatory genes and sugar transporters are similar to those in free-living organisms. Some of the predicted pathogenicity genes appear to have been acquired by lateral transfer and include genes for cellulase, pectinase, wilt-inducing protein, lysozyme, and desaturase. The presence of the latter may contribute to stunting, since it is likely involved in the synthesis of abscisic acid, a hormone that arrests growth. Our findings are consistent with the nutritionally fastidious behavior exhibited by L. xyli subsp. xyli and suggest an ongoing adaptation to the restricted ecological niche it inhabits.


Subject(s)
Actinomycetales/genetics , Genome, Bacterial , Actinomycetales/classification , Base Composition , Genes, Bacterial , Molecular Sequence Data , Pseudogenes , Saccharum/microbiology
19.
Mem Inst Oswaldo Cruz ; 99(2): 153-8, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15250468

ABSTRACT

The first and second internal transcribed spacer regions (ITS1 and ITS2) of the ribosomal DNA of Biomphalaria tenagophila complex (B. tenagophila, B. occidentalis, and B. t. guaibensis) were sequenced and compared. The alignment lengths of these regions were about 655 bp and 481 bp, respectively. Phylogenetic relationships among the Biomphalaria species were inferred by Maximum Parsimony and Neighbor-joining methods. The phylogenetic trees produced, in most of the cases, were in accordance with morphological systematics and other molecular data previously obtained by polymerase chain reaction and restriction fragment length polymorphism analysis. The present results provide support for the proposal that B. tenagophila represents a complex comprising B. tenagophila, B. occidentalis and B. t. guaibensis.


Subject(s)
Biomphalaria/genetics , DNA, Helminth/genetics , DNA, Ribosomal Spacer/genetics , Phylogeny , Animals , Base Sequence , Biomphalaria/classification , Molecular Sequence Data , Polymerase Chain Reaction
20.
Oral Oncol ; 40(6): 604-10, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15063389

ABSTRACT

Squamous cell carcinoma of the upper aerodigestive tract (UADT) is associated with environmental factors, especially tobacco and alcohol consumption. Genetic factors, including cyclin D1 (CCND1) polymorphism have been suggested to play an important role in tumorigenesis and progression of UADT cancer. To investigate the relationship between CCND1 polymorphism on susceptibility for UADT cancers, 147 cancer and 135 non-cancer subjects were included in this study. CCND1 genotype at codon 242(G870A) in exon 4 was undertaken using denaturing high performance liquid chromatography (DHPLC) and DNA sequencing. Significant odds ratio (OR) of the AA+GA genotypes [OR=7.5 (95% CI: 1.4-39.7)] was observed in non-drinkers but for non-smokers a non-significant [OR=5.4 (95% CI: 0.9-31.4)] was found in the adjusted model. These results suggest that allele A may be a risk factor for UADT cancer, especially in non-alcoholics. However, further epidemiological studies are needed to establish the exact role of CCND1 polymorphism and the development of UADT cancers.


Subject(s)
Carcinoma, Squamous Cell/genetics , Cyclin D1/genetics , Head and Neck Neoplasms/genetics , Polymorphism, Genetic/genetics , Adult , Age Factors , Aged , Aged, 80 and over , Alleles , Female , Genotype , Humans , Hypopharyngeal Neoplasms/genetics , Laryngeal Neoplasms/genetics , Male , Middle Aged , Mouth Neoplasms/genetics , Oropharyngeal Neoplasms/genetics , Risk Factors
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