RESUMO
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.
Assuntos
Antígenos de Neoplasias/sangue , Antígenos de Neoplasias/metabolismo , Medula Óssea/metabolismo , Regulação Neoplásica da Expressão Gênica , Mieloma Múltiplo/fisiopatologia , Idoso , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/metabolismo , Valor Preditivo dos Testes , Prognóstico , Padrões de Referência , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
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.
Assuntos
RNA Helicases DEAD-box/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Chaperonas Moleculares/genética , Mieloma Múltiplo/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas Serina-Treonina Quinases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Transplante de Medula Óssea , Primers do DNA , Feminino , Humanos , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/cirurgia , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Sindecana-1/análise , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Regulação para CimaRESUMO
This study aims to analyze the expression of 14 cancer/testis (CT) antigens in multiple myeloma (MM) to identify possible prognostic markers and therapeutic targets. The expression of MAGEA1, MAGEA2, MAGEA3/6, MAGEA4, MAGEA10, MAGEA12, BAGE1, MAGEC1/CT7, the GAGE family, LAGE-1, PRAME, NY-ESO-1, SPA17 and SSX1 was studied by RT-PCR in 15 normal tissues, a pool of 10 normal bone marrow samples, 3 normal tonsils and bone marrow aspirates from 6 normal donors, 3 monoclonal gammopathies of undetermined significance (MGUS), 5 solitary plasmacytomas, 39 MM samples (95% advanced stage) and the MM cell line U266. MAGEC1/CT7 was expressed in bone marrow aspirates from one MGUS and one plasmacytoma. The frequencies at which CT antigen were found to be expressed in MM patients were MAGEC1/CT7 77%, LAGE-1 49%, MAGEA3/6 41%, MAGEA2 36%, GAGE family 33%, NY-ESO-1 33%, BAGE-1 28%, MAGEA1 26%, PRAME 23%, SSX-1 26%, MAGEA12 20.5%, MAGEA4 0%, and MAGEA10 0%. Cox's regression model showed that GAGE family expression and having >6 CT antigens expressed were independent prognostic factors when all patients were analyzed. However, MAGEC1/CT7 expression was the only independent prognostic factor when non-transplanted patients where analyzed. Based on our findings, MAGEC1/CT7, MAGEA3/6 and LAGE-1 are good candidates for immunotherapy, since together they cover 85% of our MM cases. Furthermore, expression of the GAGE family, >6 CT antigens and MAGEC1/CT7 seem to have impact on MM prognosis.
