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1.
Oncotarget ; 12(5): 412-421, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33747357

RESUMO

INTRODUCTION: Calcium-binding tyrosine phosphorylation-regulated protein (CABYR) is expressed in the human germ line but not in adult human tissues, thus, it is considered a cancer testis protein. The aim of this study is to evaluate the CABYR isoforms: a/b and c mRNA expression in colorectal cancer (CRC) and to determine if these proteins hold promise as vaccine targets. MATERIALS AND METHODS: CABYR mRNA expression in a set of normal human tissues, including the testis, were determined and compared using semi-quantitative PCR. As regards the tumor and normal mucosal samples from study patients, RNA was extracted and cDNA generated after which quantitative PCR was carried out. Analysis of CABYR protein expressions by immunohistochemistry in tumor and normal colon tissues was also performed. RESULTS: A total of 47 paired CRC and normal tissue specimens were studied. The percent of patients with a relative expression ratio of malignant to normal (M/N) tissues over 1 was 70% for CABYR a/b and 72% for CABYR c. The percent with both a M/N ratio over 1 and expression levels over 0.1% of testis was 23.4% for CABYR-a/b and 25.5% for CABYR c. CABYR expression in tumors was further confirmed by immunohistochemistry. CONCLUSIONS: CABYR a/b and c hold promise as specific immunotherapy targets, however, a larger and more diverse group of tumors (Stage 1-4) needs to be assessed and evaluation of blood for anti-CABYR antibodies is needed to pursue this concept.

2.
Oncoscience ; 4(9-10): 139-147, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29142905

RESUMO

INTRODUCTION: Placental-Cadherin (CDH3) is a cell adhesion molecule vital to cellular localization and tissue integrity. It is highly expressed in the placenta (PLC)and is overexpressed by many types of cancer. P-cadherin levels in colorectal cancer (CRC) remains poorly characterized. This study's purpose was to determine P-cadherin expression in CRC and normal tissues and to assess plasma CDH3 levels in order to determine the relationship, if any, between cancer stage, P-cadherin expression and plasma CDH3 levels. METHODS: An IRB approved plasma, tumor, and prospective data bank was utilized. CRC patients for whom tumor and normal colon tissue samples were available were enrolled. Tumor samples were OCT embedded and stored at -80C°. Total purified RNA was isolated from tissue samples and cDNA synthesized. CDH3 expression was analyzed by quantitative PCR (QPCR) using the SYBR Green platform. Tumor expression levels were determined and compared to levels in normal colonic tissue and PLC. Expression in 22 different normal tissues was also assessed by RT-PCR. Plasma CDH3 levels were determined via ELISA in patients for whom preoperative blood samples were available. Results: A total of 77 paired CRC and normal colon specimens (36 M/ 41 F, age 67.3±14.5) were assessed (82% colon, 18% rectal; Cancer Stage 2, 44; Stage 3, 33). All tested tumors had CDH3 expression levels over 0.1% of the PLC level and tumor to normal colon ratios greater than 1. CDH3 expression was noted in 14/22 normal organ tissues. There was a positive correlation between tumor CDH3 QPCR and preoperative CDH3 blood levels (n=57, P= 0.038). Expression levels were significantly higher in rectal vs. colon tumors (p=0.019). Conclusion: CDH3 expression was elevated in CRC tumors as compared to normal tissue. CDH3 was expressed by numerous normal organs and, thus, is not a viable vaccine target, however, the correlation between plasma and tumor CDH3 levels suggests CDH3 may have value as a diagnostic or prognostic marker.

3.
Oncoscience ; 4(3-4): 33-40, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28540335

RESUMO

BACKGROUND: At present, it is difficult to predict which patients with ductal carcinoma-in-situ (DCIS) will subsequently develop frank invasive breast cancer (IDC). A recent survey by our group has shown that NY-ESO-1 and MAGEA are both expressed in DCIS. This study was aimed at determining whether expression of these antigens was related to the later development of IDC. RESULTS: 14 of 42 (33%) of patients developed invasive breast cancer during the follow up period. Only one of those DCIS cases that relapsed was positive for NYESO-1 at diagnosis. In contrast, DCIS samples of 15 of the 28 (54%) of those patients who remained disease-free expressed NY-ESO-1. (Permutation chi square p=0.0033). METHODS: We identified 42 patients with DCIS, and followed them up for more than 10 years. NY-ESO-1 and MAGEA were demonstrated by immunostaining as were CD8+ infiltrates on all sections together with the conventional markers, ER, PR, and HER2. CONCLUSIONS: Expression of NY-ESO-1 may predict those patients who will not subsequently develop invasive breast cancer and could therefore potentially be helpful in defining prognosis in patients with DCIS.

5.
Cancer Immunol Res ; 4(6): 552-61, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27045022

RESUMO

Melanoma is one of the major cancer types for which new immune-based cancer treatments have achieved promising results. However, anti-PD-1 and anti-CTLA-4 therapies are effective only in some patients. Hence, predictive molecular markers for the development of clinical strategies targeting immune checkpoints are needed. Using The Cancer Genome Atlas (TCGA) RNAseq data, we found that expression of ESRP1, encoding a master splicing regulator in the epithelial-mesenchymal transition (EMT), was inversely correlated with tumor-associated immune cytolytic activity. That association holds up across multiple TCGA tumor types, suggesting a link between tumor EMT status and infiltrating lymphocyte activity. In melanoma, ESRP1 mainly exists in a melanocyte-specific truncated form transcribed from exon 13. This was validated by analyzing CCLE cell line data, public CAGE data, and RT-PCR in primary cultured melanoma cell lines. Based on ESRP1 expression, we divided TCGA melanoma cases into ESRP1-low, -truncated, and -full-length groups. ESRP1-truncated tumors comprise approximately two thirds of melanoma samples and reside in an apparent transitional state between epithelial and mesenchymal phenotypes. ESRP1 full-length tumors express epithelial markers and constitute about 5% of melanoma samples. In contrast, ESRP1-low tumors express mesenchymal markers and are high in immune cytolytic activity as well as PD-L2 and CTLA-4 expression. Those tumors are associated with better patient survival. Results from our study suggest a path toward the use of ESRP1 and other EMT markers as informative biomarkers for immunotherapy. Cancer Immunol Res; 4(6); 552-61. ©2016 AACR.


Assuntos
Processamento Alternativo , Biomarcadores Tumorais/metabolismo , Transição Epitelial-Mesenquimal/genética , Melanoma/metabolismo , Proteínas de Ligação a RNA/metabolismo , Biomarcadores Tumorais/genética , Citotoxicidade Imunológica/genética , Citotoxicidade Imunológica/imunologia , Bases de Dados Genéticas , Regulação Neoplásica da Expressão Gênica , Humanos , Melanócitos/metabolismo , Melanoma/genética , Melanoma/imunologia , Melanoma/secundário , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Prognóstico , Proteínas de Ligação a RNA/genética , Transcriptoma
6.
Oncoscience ; 2(6): 607-14, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26244168

RESUMO

INTRODUCTION: IGF2BP3 (IMP3) is a mRNA binding protein that regulates IGF2 translation and function during embryogenesis. Because IGF2BP3 is undetectable in adult human tissues except the testis, and increased IGF2BP3 expression has been noted in several cancers, it is considered a cancer testis (CT) protein. IGF2BP3 mRNA expression in colorectal cancers (CRC) has not been well studied. This study's aim was to quantitatively assess IGF2BP3 mRNA expression in CRC and, thus, determine if IGF2BP3 has potential as a vaccine target. METHOD: Data were collected prospectively from CRC patients in an IRB-approved tissue and data bank. Total RNA was isolated and purified from tumor and normal colonic tissue samples and cDNA synthesized. IGF2BP3 expression was analyzed by quantitative PCR (QPCR). Expression levels of IGF2BP3 in tumors and testis were determined and compared. Tumors with levels greater than 0.1% or more of the testis levels were considered positive. Analysis of IGF2BP3 protein expression by immunohistochemistry (IHC) in tumor and normal tissues was also performed. RESULTS: A total of 84 paired tumor and normal tissue specimens were assessed from patients with Stage 2 and 3 CRC; 43% of tumors had IGF2BP3 mRNA expression levels greater than 0.1 % of that of testis and were considered positive. The median tumor expression level was higher in women (p=0.042). No correlation was found between IGF2BP3 mRNA expression and tumor stage or lymph node involvement. IHC was carried out on paired tumor and normal tissue sections from 46 patients; IGF2BP3 staining was noted in 50% of the tumor sections and in 5% of the normal tissue sections. DISCUSSION: IGF2BP3 mRNA was over expressed in 43% of the tumors whereas the protein was noted in 50% of samples. No correlation between mRNA expression and disease severity was noted. This protein holds promise as a vaccine target, however, a larger study that assesses a more diverse population of patients (Stage 1-4) as well as a study of preoperative serum samples for auto-antibodies to IGF2BP3 are needed to pursue this concept.

7.
J Neurooncol ; 119(1): 59-70, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24797829

RESUMO

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.


Assuntos
Antígenos CD/metabolismo , Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Moléculas de Adesão Celular/metabolismo , Movimento Celular/genética , Placenta/metabolismo , Regulação para Cima , Antígeno 12E7 , Antígenos CD/genética , Astrocitoma/genética , Astrocitoma/patologia , Encéfalo/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Gradação de Tumores , Gravidez
9.
Cancer Immunol Res ; 2(4): 371-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24764584

RESUMO

Cancer-testis (CT) antigens are potential targets for cancer immunotherapy because of their restricted expression in immune-privileged germ cells and various malignancies. Current application of CT-based immunotherapy has been focused on CT expression-rich tumors such as melanoma and lung cancers. In this study, we surveyed CT expression using The Cancer Genome Atlas (TCGA) datasets for ten common cancer types. We show that CT expression is specific and enriched within certain cancer molecular subtypes. For example, HORMAD1, CXorf61, ACTL8, and PRAME are highly enriched in the basal subtype of breast cancer; MAGE and CSAG are most frequently activated in the magnoid subtype of lung adenocarcinoma; and PRAME is highly upregulated in the ccB subtype of clear cell renal cell carcinoma. Analysis of CT gene expression and DNA methylation indicates that some CTs are regulated epigenetically, whereas others are controlled primarily by tissue- and subtype-specific transcription factors. Our results suggest that although for some CT expression is associated with patient outcome, not many are independent prognostic markers. Thus, CTs with shared expression pattern are heterogeneous molecules with distinct activation modes and functional properties in different cancers and cancer subtypes. These data suggest a cancer subtype-orientated application of CT antigen as biomarkers and immunotherapeutic targets.


Assuntos
Antígenos de Neoplasias/imunologia , Biomarcadores Tumorais , Imunoterapia , Neoplasias/imunologia , Neoplasias/terapia , Análise de Variância , Antígenos de Neoplasias/genética , Análise por Conglomerados , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/mortalidade , Prognóstico
10.
Oncoscience ; 1(1): 14-20, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25593980

RESUMO

Cancer/testis (CT) genes represent a unique class of genes, which are expressed by germ cells, normally silenced in somatic cells, but activated in various cancers. CT proteins can elicit spontaneous immune responses in cancer patients and this feature makes them attractive targets for immunotherapy-based approaches. We have previously reported that CTs are relatively commonly expressed in estrogen receptor (ER) negative, high risk carcinomas. In this study, we examined the expression of selected CT genes in ductal carcinoma in situ (DCIS), lobular carcinoma in situ (LCIS) and benign proliferative lesions of the breast. ER negative DCIS were found to be associated with significant CT gene expression together with HER2 positivity and a marked stromal immune response.

11.
PLoS One ; 8(12): e83212, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24340093

RESUMO

The Cancer/Testis (CT) antigen family of genes are transcriptionally repressed in most human tissues but are atypically re-expressed in many malignant tumour types. Their restricted expression profile makes CT antigens ideal targets for cancer immunotherapy. As little is known about whether CT antigens may be regulated by post-translational processing, we investigated the mechanisms governing degradation of NY-ESO-1 and MAGE-C1 in selected cancer cell lines. Inhibitors of proteasome-mediated degradation induced the partitioning of NY-ESO-1 and MAGE-C1 into a detergent insoluble fraction. Moreover, this treatment also resulted in increased localisation of NY-ESO-1 and MAGE-C1 at the centrosome. Despite their interaction, relocation of either NY-ESO-1 or MAGE-C1 to the centrosome could occur independently of each other. Using a series of truncated fragments, the regions corresponding to NY-ESO-1(91-150) and MAGE-C1(900-1116) were established as important for controlling both stability and localisation of these CT antigens. Our findings demonstrate that the steady state levels of NY-ESO-1 and MAGE-C1 are regulated by proteasomal degradation and that both behave as aggregation-prone proteins upon accumulation. With proteasome inhibitors being increasingly used as front-line treatment in cancer, these data raise issues about CT antigen processing for antigenic presentation and therefore immunogenicity in cancer patients.


Assuntos
Antígenos de Neoplasias/metabolismo , Centrossomo/imunologia , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/imunologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Apresentação de Antígeno , Linhagem Celular Tumoral , Centrossomo/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imunoterapia , Camundongos , Células NIH 3T3 , Inibidores de Proteassoma/química , Estrutura Terciária de Proteína , RNA Interferente Pequeno/metabolismo
12.
Proc Natl Acad Sci U S A ; 110(50): 20212-7, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24277834

RESUMO

An autochthonous model of pancreatic ductal adenocarcinoma (PDA) permitted the analysis of why immunotherapy is ineffective in this human disease. Despite finding that PDA-bearing mice had cancer cell-specific CD8(+) T cells, the mice, like human patients with PDA, did not respond to two immunological checkpoint antagonists that promote the function of T cells: anti-cytotoxic T-lymphocyte-associated protein 4 (α-CTLA-4) and α-programmed cell death 1 ligand 1 (α-PD-L1). Immune control of PDA growth was achieved, however, by depleting carcinoma-associated fibroblasts (CAFs) that express fibroblast activation protein (FAP). The depletion of the FAP(+) stromal cell also uncovered the antitumor effects of α-CTLA-4 and α-PD-L1, indicating that its immune suppressive activity accounts for the failure of these T-cell checkpoint antagonists. Three findings suggested that chemokine (C-X-C motif) ligand 12 (CXCL12) explained the overriding immunosuppression by the FAP(+) cell: T cells were absent from regions of the tumor containing cancer cells, cancer cells were coated with the chemokine, CXCL12, and the FAP(+) CAF was the principal source of CXCL12 in the tumor. Administering AMD3100, a CXCL12 receptor chemokine (C-X-C motif) receptor 4 inhibitor, induced rapid T-cell accumulation among cancer cells and acted synergistically with α-PD-L1 to greatly diminish cancer cells, which were identified by their loss of heterozygosity of Trp53 gene. The residual tumor was composed only of premalignant epithelial cells and inflammatory cells. Thus, a single protein, CXCL12, from a single stromal cell type, the FAP(+) CAF, may direct tumor immune evasion in a model of human PDA.


Assuntos
Carcinoma Ductal Pancreático/terapia , Quimiocina CXCL12/metabolismo , Gelatinases/metabolismo , Imunoterapia/métodos , Proteínas de Membrana/metabolismo , Neoplasias Pancreáticas/terapia , Serina Endopeptidases/metabolismo , Evasão Tumoral/genética , Análise de Variância , Animais , Sequência de Bases , Benzilaminas , Carcinoma Ductal Pancreático/imunologia , Ciclamos , Endopeptidases , ELISPOT , Fibroblastos/metabolismo , Citometria de Fluxo , Imunofluorescência , Compostos Heterocíclicos , Imuno-Histoquímica , Camundongos , Dados de Sequência Molecular , Neoplasias Pancreáticas/imunologia , Análise de Sequência de RNA
13.
Front Genet ; 4: 209, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24194746

RESUMO

PROM1 is the gene encoding prominin-1 or CD133, an important cell surface marker for the isolation of both normal and cancer stem cells. PROM1 transcripts initiate at a range of transcription start sites (TSS) associated with distinct tissue and cancer expression profiles. Using high resolution Cap Analysis of Gene Expression (CAGE) sequencing we characterize TSS utilization across a broad range of normal and developmental tissues. We identify a novel proximal promoter (P6) within CD133(+) melanoma cell lines and stem cells. Additional exon array sampling finds P6 to be active in populations enriched for mesenchyme, neural stem cells and within CD133(+) enriched Ewing sarcomas. The P6 promoter is enriched with respect to previously characterized PROM1 promoters for a HMGI/Y (HMGA1) family transcription factor binding site motif and exhibits different epigenetic modifications relative to the canonical promoter region of PROM1.

14.
BMC Med Genomics ; 6: 40, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-24119551

RESUMO

BACKGROUND: Intratumoral heterogeneity is a major obstacle for the treatment of cancer, as the presence of even minor populations that are insensitive to therapy can lead to disease relapse. Increased clonal diversity has been correlated with a poor prognosis for cancer patients, and we therefore examined genetic, transcriptional, and functional diversity in metastatic melanoma. METHODS: Amplicon sequencing and SNP microarrays were used to profile somatic mutations and DNA copy number changes in multiple regions from metastatic lesions. Clonal genetic and transcriptional heterogeneity was also assessed in single cell clones from early passage cell lines, which were then subjected to clonogenicity and drug sensitivity assays. RESULTS: MAPK pathway and tumor suppressor mutations were identified in all regions of the melanoma metastases analyzed. In contrast, we identified copy number abnormalities present in only some regions in addition to homogeneously present changes, suggesting ongoing genetic evolution following metastatic spread. Copy number heterogeneity from a tumor was represented in matched cell line clones, which also varied in their clonogenicity and drug sensitivity. Minor clones were identified based on dissimilarity to the parental cell line, and these clones were the most clonogenic and least sensitive to drugs. Finally, treatment of a polyclonal cell line with paclitaxel to enrich for drug-resistant cells resulted in the adoption of a gene expression profile with features of one of the minor clones, supporting the idea that these populations can mediate disease relapse. CONCLUSION: Our results support the hypothesis that minor clones might have major consequences for patient outcomes in melanoma.


Assuntos
Variação Genética , Melanoma/genética , Melanoma/patologia , Linhagem Celular Tumoral , Células Clonais/patologia , Variações do Número de Cópias de DNA , Feminino , Humanos , Masculino , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Transcriptoma
15.
J Exp Med ; 210(6): 1137-51, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23712428

RESUMO

Fibroblast activation protein-α (FAP) identifies stromal cells of mesenchymal origin in human cancers and chronic inflammatory lesions. In mouse models of cancer, they have been shown to be immune suppressive, but studies of their occurrence and function in normal tissues have been limited. With a transgenic mouse line permitting the bioluminescent imaging of FAP(+) cells, we find that they reside in most tissues of the adult mouse. FAP(+) cells from three sites, skeletal muscle, adipose tissue, and pancreas, have highly similar transcriptomes, suggesting a shared lineage. FAP(+) cells of skeletal muscle are the major local source of follistatin, and in bone marrow they express Cxcl12 and KitL. Experimental ablation of these cells causes loss of muscle mass and a reduction of B-lymphopoiesis and erythropoiesis, revealing their essential functions in maintaining normal muscle mass and hematopoiesis, respectively. Remarkably, these cells are altered at these sites in transplantable and spontaneous mouse models of cancer-induced cachexia and anemia. Thus, the FAP(+) stromal cell may have roles in two adverse consequences of cancer: their acquisition by tumors may cause failure of immunosurveillance, and their alteration in normal tissues contributes to the paraneoplastic syndromes of cachexia and anemia.


Assuntos
Anemia/metabolismo , Medula Óssea/metabolismo , Caquexia/metabolismo , Gelatinases/genética , Gelatinases/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Músculo Esquelético/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Células Estromais/metabolismo , Tecido Adiposo/metabolismo , Anemia/genética , Anemia/patologia , Animais , Caquexia/genética , Caquexia/patologia , Linhagem da Célula/genética , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Endopeptidases , Eritropoese/genética , Folistatina/genética , Folistatina/metabolismo , Hematopoese/genética , Linfopoese/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos/genética , Camundongos Transgênicos/metabolismo , Músculo Esquelético/citologia , Transtornos Musculares Atróficos/genética , Transtornos Musculares Atróficos/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Pâncreas/metabolismo , Células Estromais/citologia , Transcriptoma/genética
16.
Oncotarget ; 4(4): 531-41, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23625514

RESUMO

Cancer/testis (CT) genes are encoded by genes that are normally expressed only in the human germ line but which are activated in various malignancies. CT proteins are frequently immunogenic in cancer patients and their expression is highly restricted to tumors. They are thus important targets for anticancer immunotherapy. In several different tumor types, the expression of CT-X genes is associated with advanced disease and poor outcome, indicating that their expression might contribute to tumorigenesis. CT-X genes encoding members of the MAGE protein family on Xq28 have been shown to potentially influence the tumorigenic phenotype. We used small interfering RNA (siRNA) to investigate whether CT-X mapping to the short arm of the X-chromosome might also have tumorigenic properties and therefore be potentially targeted by functional inhibitors in a therapeutic setting. siRNAs specific to GAGE, SSX and XAGE1 were used in cell proliferation, migration and cell survival assays using cell lines derived from melanoma, a tumor type known to present high frequencies of expression of CT antigens. We found that of these, those specific to GAGE and XAGE1 most significantly impeded melanoma cell migration and invasion and those specific to SSX4 and XAGE1 decreased the clonogenic survival of melanoma cells. Our results suggest that GAGE, XAGE1 and SSX4 might each have a role in tumor progression and are possible therapeutic targets for the treatment of melanoma and other malignancies.


Assuntos
Antígenos de Neoplasias/genética , Genes Ligados ao Cromossomo X/genética , Melanoma/genética , Proteínas de Neoplasias/genética , Proteínas Repressoras/genética , Western Blotting , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Técnicas de Silenciamento de Genes , Humanos , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
17.
Cancer Cell ; 23(5): 618-33, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23623661

RESUMO

Nearly 90% of human melanomas contain inactivated wild-type p53, the underlying mechanisms for which are not fully understood. Here, we identify that cyclin B1/CDK1-phosphorylates iASPP, which leads to the inhibition of iASPP dimerization, promotion of iASPP monomer nuclear entry, and exposure of its p53 binding sites, leading to increased p53 inhibition. Nuclear iASPP is enriched in melanoma metastasis and associates with poor patient survival. Most wild-type p53-expressing melanoma cell lines coexpress high levels of phosphorylated nuclear iASPP, MDM2, and cyclin B1. Inhibition of MDM2 and iASPP phosphorylation with small molecules induced p53-dependent apoptosis and growth suppression. Concurrent p53 reactivation and BRAFV600E inhibition achieved additive suppression in vivo, presenting an alternative for melanoma therapy.


Assuntos
Proteína Quinase CDC2/fisiologia , Ciclina B1/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Melanoma/metabolismo , Proteínas Repressoras/metabolismo , Proteína Supressora de Tumor p53/fisiologia , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Ciclina B1/genética , Ciclina B1/metabolismo , Dimerização , Humanos , Imidazóis/farmacologia , Indóis/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/análise , Pontos de Checagem da Fase M do Ciclo Celular , Melanoma/genética , Melanoma/patologia , Camundongos , Metástase Neoplásica , Nocodazol/farmacologia , Fosforilação/efeitos dos fármacos , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/análise , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Repressoras/análise , Sulfonamidas/farmacologia , Triazóis/farmacologia , Vemurafenib , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Clin Cancer Res ; 19(9): 2460-72, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23444225

RESUMO

PURPOSE: We aim to identify tumor-specific alternative splicing events having potential applications in the early detection, diagnosis, prognosis, and therapy for cancers. EXPERIMENTAL DESIGN: We analyzed RNA-seq data on 470 clear cell renal cell carcinomas (ccRCC) and 68 kidney tissues to identify tumor-specific alternative splicing events. We further focused on the fibroblast growth factor receptor 2 (FGFR2) isoform switch and characterized ccRCCs expressing different FGFR2 isoforms by integrated analyses using genomic data from multiple platforms and tumor types. RESULTS: We identified 113 top candidate alternatively spliced genes in ccRCC. Prominently, the FGFR2 gene transcript switched from the normal IIIb isoform ("epithelial") to IIIc isoform ("mesenchymal") in nearly 90% of ccRCCs. This switch is kidney specific as it was rarely observed in other cancers. The FGFR2-IIIb ccRCCs show a transcriptome and methylome resembling those from normal kidney, whereas FGFR2-IIIc ccRCCs possess elevated hypoxic and mesenchymal expression signatures. Clinically, FGFR2-IIIb ccRCCs are smaller in size, of lower tumor grade, and associated with longer patient survival. Gene set enrichment and DNA copy number analyses indicated that FGFR2-IIIb ccRCCs are closely associated with renal oncocytomas and chromophobe RCCs (chRCC). A reexamination of tumor histology by pathologists identified FGFR2-IIIb tumors as chRCCs and clear cell papillary RCCs (ccpRCC). CONCLUSIONS: FGFR2 IIIb RCCs represent misdiagnosed ccRCC cases, suggesting FGFR2 isoform testing can be used in the diagnosis of RCC subtypes. The finding of a prevalent isoform switch of FGFR2 in a tissue-specific manner holds promise for the future development of FGFR2-IIIc as a distinct early detection biomarker and therapeutic target for ccRCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Neoplasias Renais/patologia , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Processamento Alternativo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Estudos de Casos e Controles , Análise por Conglomerados , Metilação de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Éxons , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/metabolismo , Especificidade de Órgãos , Fenótipo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Análise de Sequência de RNA , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
19.
Cancer Immunol Res ; 1(5): 296-302, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24777967

RESUMO

Meningiomas are the most common primary intracranial tumors. Surgical resection remains the treatment of choice for these tumors. However, a significant number of tumors are not surgically accessible, recur, or become malignant, necessitating the repetition of surgery and sometimes radiation. Chemotherapy is rarely used and is generally not recognized as an effective treatment. Cancer/testis (CT) genes represent a unique class of genes, which are expressed by germ cells, normally silenced in somatic cells, but activated in various cancers. CT proteins can elicit spontaneous immune responses in patients with cancer and this feature makes them attractive targets for immunotherapy-based approaches. We analyzed mRNA expression of 37 testis-restricted CT genes in a discovery set of 18 meningiomas by reverse transcription PCR. The overall frequency of expression of CT genes ranged from 5.6% to 27.8%. The most frequently expressed was NY-ESO-1, in 5 patients (27.8%). We subsequently analyzed NY-ESO-1 protein expression in a larger set of meningiomas by immunohistochemistry and found expression in 108 of 110 cases. In some cases, NY-ESO-1 expression was diffused and homogenous, but in most instances it was heterogeneous. Importantly, NY-ESO-1 expression was positively correlated with higher grade and patients presenting with higher levels of NY-ESO-1 staining had significantly worse disease-free and overall survival. We have also shown that NY-ESO-1 expression may lead to humoral immune response in patients with meningioma. Considering the limited treatment options for patients with meningioma, the potential of NY-ESO-1-based immunotherapy should be explored.


Assuntos
Antígenos de Neoplasias/biossíntese , Proteínas de Membrana/biossíntese , Neoplasias Meníngeas/imunologia , Neoplasias Meníngeas/terapia , Meningioma/imunologia , Meningioma/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antineoplásicos/biossíntese , Anticorpos Antineoplásicos/genética , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Imunoterapia/métodos , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Neoplasias Meníngeas/genética , Meningioma/genética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/terapia , Adulto Jovem
20.
PLoS One ; 7(10): e48240, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23133577

RESUMO

Starting from publicly-accessible datasets, we have utilized comparative and phylogenetic genome analyses to characterize the evolution of the human MAGE gene family. Our characterization of genomic structures in representative genomes of primates, rodents, carnivora, and macroscelidea indicates that both Type I and Type II MAGE genes have undergone lineage-specific evolution. The restricted expression pattern in germ cells of Type I MAGE orthologs is observed throughout evolutionary history. Unlike Type II MAGEs that have conserved promoter sequences, Type I MAGEs lack promoter conservation, suggesting that epigenetic regulation is a central mechanism for controlling their expression. Codon analysis shows that Type I but not Type II MAGE genes have been under positive selection. The combination of genomic and expression analysis suggests that Type 1 MAGE promoters and genes continue to evolve in the hominin lineage, perhaps towards functional diversification or acquiring additional specific functions, and that selection pressure at codon level is associated with expression spectrum.


Assuntos
Regulação da Expressão Gênica , Antígenos Específicos de Melanoma/genética , Antígenos Específicos de Melanoma/fisiologia , Animais , Evolução Biológica , Bases de Dados Genéticas , Cães , Elefantes , Evolução Molecular , Genômica , Humanos , Funções Verossimilhança , Macaca mulatta , Camundongos , Família Multigênica , Pan troglodytes , Filogenia , Pongo , Ratos , Especificidade da Espécie
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