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1.
ESMO Open ; 7(6): 100637, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36423362

RESUMEN

BACKGROUND: COGNITION (Comprehensive assessment of clinical features, genomics and further molecular markers to identify patients with early breast cancer for enrolment on marker driven trials) is a diagnostic registry trial that employs genomic and transcriptomic profiling to identify biomarkers in patients with early breast cancer with a high risk for relapse after standard neoadjuvant chemotherapy (NACT) to guide genomics-driven targeted post-neoadjuvant therapy. PATIENTS AND METHODS: At National Center for Tumor Diseases Heidelberg patients were biopsied before starting NACT, and for patients with residual tumors after NACT additional biopsy material was collected. Whole-genome/exome and transcriptome sequencing were applied on tumor and corresponding blood samples. RESULTS: In the pilot phase 255 patients were enrolled, among which 213 were assessable: thereof 48.8% were identified to be at a high risk for relapse following NACT; 86.4% of 81 patients discussed in the molecular tumor board were eligible for a targeted therapy within the interventional multiarm phase II trial COGNITION-GUIDE (Genomics-guided targeted post neoadjuvant therapy in patients with early breast cancer) starting enrolment in Q4/2022. An in-depth longitudinal analysis at baseline and in residual tumor tissue of 16 patients revealed some cases with clonal evolution but largely stable genetic alterations, suggesting restricted selective pressure of broad-acting cytotoxic neoadjuvant chemotherapies. CONCLUSIONS: While most precision oncology initiatives focus on metastatic disease, the presented concept offers the opportunity to empower novel therapy options for patients with high-risk early breast cancer in the post-neoadjuvant setting within a biomarker-driven trial and provides the basis to test the value of precision oncology in a curative setting with the overarching goal to increase cure rates.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/tratamiento farmacológico , Medicina de Precisión , Estudios Prospectivos
2.
Neuropathol Appl Neurobiol ; 45(2): 108-118, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30326163

RESUMEN

AIMS: Mutations of isocitrate dehydrogenase (IDH)1/2 affect almost all astrocytomas of WHO grade II and III. A subset of IDH-mutant astrocytic tumours progresses to IDH-mutant glioblastoma or presents with the histology of a glioblastoma at first presentation. We set out here to assess the molecular spectrum of IDH-mutant glioblastomas. METHODS: We performed an integrated molecular analysis of a mono-centric cohort (n = 97); assessed through genome-wide DNA methylation analysis, copy-number profiling and targeted next generation sequencing using a neurooncology-tailored gene panel. RESULTS: Of these 97 IDH-mutant glioblastomas, 68 had a glioblastoma at first presentation ('de novo' IDH-mutant glioblastoma) and 29 emerged from a prior low-grade lesion ('evolved' IDH-mutant glioblastoma). Unsupervised hierarchical clustering of DNA methylation data disclosed that IDH-mutant glioblastoma ('de novo' and 'evolved') formed a distinct group separate from other diffuse glioma subtypes. Homozygous deletions of CDKN2A/B were found to be associated with shorter survival. CONCLUSIONS: This study demonstrates DNA methylation patterns in IDH-mutant glioblastoma to be distinct from lower-grade astrocytic counterparts but homogeneous within de novo and evolved IDH-mutant glioblastomas, and identifies CDKN2A as a marker for possible genetic sub-stratification.


Asunto(s)
Astrocitoma/patología , Neoplasias Encefálicas/patología , Glioblastoma/genética , Glioma/patología , Isocitrato Deshidrogenasa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Astrocitoma/genética , Neoplasias Encefálicas/genética , Glioma/genética , Humanos , Persona de Mediana Edad , Mutación/genética , Clasificación del Tumor/métodos , Adulto Joven
3.
Oncogene ; 36(37): 5231-5242, 2017 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-28504719

RESUMEN

Group3 medulloblastoma (MBG3) that predominantly occur in young children are usually associated with MYC amplification and/or overexpression, frequent metastasis and a dismal prognosis. Physiologically relevant MBG3 models are currently lacking, making inferences related to their cellular origin thus far limited. Using in utero electroporation, we here report that MBG3 mouse models can be developed in situ from different multipotent embryonic cerebellar progenitor cells via conditional expression of Myc and loss of Trp53 function in several Cre driver mouse lines. The Blbp-Cre driver that targets embryonic neural progenitors induced tumors exhibiting a large-cell/anaplastic histopathology adjacent to the fourth ventricle, recapitulating human MBG3. Enforced co-expression of luciferase together with Myc and a dominant-negative form of Trp53 revealed that GABAergic neuronal progenitors as well as cerebellar granule cells give rise to MBG3 with their distinct growth kinetics. Cross-species gene expression analysis revealed that these novel MBG3 models shared molecular characteristics with human MBG3, irrespective of their cellular origin. We here developed MBG3 mouse models in their physiological environment and we show that oncogenic insults drive this MB subgroup in different cerebellar lineages rather than in a specific cell of origin.


Asunto(s)
Neoplasias Cerebelosas/genética , Cerebelo/embriología , Cerebelo/patología , Meduloblastoma/genética , Proteínas Proto-Oncogénicas c-myc/genética , Animales , Neoplasias Cerebelosas/metabolismo , Neoplasias Cerebelosas/patología , Cerebelo/citología , Cerebelo/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Meduloblastoma/metabolismo , Meduloblastoma/patología , Ratones , Ratones Transgénicos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transfección
4.
Oncogene ; 36(29): 4124-4134, 2017 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-28319069

RESUMEN

Antiestrogen-resistant and triple-negative breast tumors pose a serious clinical challenge because of limited treatment options. We assessed global gene expression changes in antiestrogen-sensitive compared with antiestrogen-resistant (two tamoxifen resistant and two fulvestrant resistant) MCF-7 breast cancer cell lines. The branched-chain amino acid transaminase 1 (BCAT1), which catalyzes the first step in the breakdown of branched-chain amino acids, was among the most upregulated transcripts in antiestrogen-resistant cells. Elevated BCAT1 expression was confirmed in relapsed tamoxifen-resistant breast tumor specimens. High intratumoral BCAT1 levels were associated with a reduced relapse-free survival in adjuvant tamoxifen-treated patients and overall survival in unselected patients. On a tissue microarray (n=1421), BCAT1 expression was detectable in 58% of unselected primary breast carcinomas and linked to a higher Ki-67 proliferation index, as well as histological grade. Interestingly, BCAT1 was predominantly expressed in estrogen receptor-α-negative/human epidermal growth factor receptor-2-positive (ERα-negative/HER-2-positive) and triple-negative breast cancers in independent patient cohorts. The inverse relationship between BCAT1 and ERα was corroborated in various breast cancer cell lines and pharmacological long-term depletion of ERα induced BCAT1 expression in vitro. Mechanistically, BCAT1 indirectly controlled expression of the cell cycle inhibitor p27Kip1 thereby affecting pRB. Correspondingly, phenotypic analyses using a lentiviral-mediated BCAT1 short hairpin RNA knockdown revealed that BCAT1 sustains proliferation in addition to migration and invasion and that its overexpression enhanced the capacity of antiestrogen-sensitive cells to grow in the presence of antiestrogens. Importantly, silencing of BCAT1 in an orthotopic triple-negative xenograft model resulted in a massive reduction of tumor volume in vivo, supporting our findings that BCAT1 is necessary for the growth of hormone-independent breast tumors.


Asunto(s)
Neoplasias de la Mama/metabolismo , Antagonistas de Estrógenos/farmacología , Receptor alfa de Estrógeno/metabolismo , Transaminasas/genética , Animales , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Resistencia a Antineoplásicos , Femenino , Perfilación de la Expresión Génica , Xenoinjertos , Humanos , Células MCF-7 , Ratones , Ratones Endogámicos BALB C , Tamoxifeno/farmacología , Transaminasas/antagonistas & inhibidores , Transaminasas/biosíntesis , Transaminasas/metabolismo , Regulación hacia Arriba
5.
Leukemia ; 31(10): 2048-2056, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28196983

RESUMEN

Recent developments in sequencing technologies led to the discovery of a novel form of genomic instability, termed chromothripsis. This catastrophic genomic event, involved in tumorigenesis, is characterized by tens to hundreds of simultaneously acquired locally clustered rearrangements on one chromosome. We hypothesized that leukemias developing in individuals with Ataxia Telangiectasia, who are born with two mutated copies of the ATM gene, an essential guardian of genome stability, would show a higher prevalence of chromothripsis due to the associated defect in DNA double-strand break repair. Using whole-genome sequencing, fluorescence in situ hybridization and RNA sequencing, we characterized the genomic landscape of Acute Lymphoblastic Leukemia (ALL) arising in patients with Ataxia Telangiectasia. We detected a high frequency of chromothriptic events in these tumors, specifically on acrocentric chromosomes, as compared with tumors from individuals with other types of DNA repair syndromes (27 cases total, 10 with Ataxia Telangiectasia). Our data suggest that the genomic landscape of Ataxia Telangiectasia ALL is clearly distinct from that of sporadic ALL. Mechanistically, short telomeres and compromised DNA damage response in cells of Ataxia Telangiectasia patients may be linked with frequent chromothripsis. Furthermore, we show that ATM loss is associated with increased chromothripsis prevalence in additional tumor entities.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/fisiología , Ataxia Telangiectasia/genética , Proteínas de Neoplasias/fisiología , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Ataxia Telangiectasia/complicaciones , Proteínas de la Ataxia Telangiectasia Mutada/deficiencia , Proteínas de la Ataxia Telangiectasia Mutada/genética , Niño , Preescolar , Cromosomas Humanos/ultraestructura , Cromotripsis , Reparación del ADN/genética , ADN de Neoplasias/genética , Femenino , Genoma Humano , Inestabilidad Genómica , Humanos , Hibridación Fluorescente in Situ , Masculino , Mutación , Proteínas de Neoplasias/deficiencia , Proteínas de Neoplasias/genética , Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , ARN Neoplásico/genética , Análisis de Secuencia de ADN , Análisis de Secuencia de ARN , Acortamiento del Telómero/genética , Transcriptoma
6.
Leukemia ; 30(3): 570-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26522085

RESUMEN

Chronic lymphocytic leukemia (CLL) is characterized by apoptosis resistance and a dysfunctional immune system. Previous reports suggested a potential role of myeloid cells in mediating these defects. However, the composition and function of CLL-associated myeloid cells have not been thoroughly investigated in vivo. Using the Eµ-TCL1 mouse model, we observed severe skewing of myeloid cell populations with CLL development. Monocytes and M2-like macrophages infiltrated the peritoneal cavity of leukemic mice. Monocytes also accumulated in the spleen in a CCR2-dependent manner, and were severely skewed toward Ly6C(low) patrolling or nonclassical phenotype. In addition, the percentage of MHC-II(hi) dendritic cells and macrophages significantly dropped in the spleen. Gene expression profiling of CLL-associated monocytes revealed aberrantly high PD-L1 expression and secretion of multiple inflammatory and immunosuppressive cytokines like interleukin-10, tumor necrosis factor-α and CXCL9. In vivo myeloid cell depletion using liposomal Clodronate resulted in a significant control of CLL development accompanied by a pronounced repair of innate immune cell phenotypes and a partial resolution of systemic inflammation. In addition, CLL-associated skewing of T cells toward antigen-experienced phenotypes was repaired. The presented data suggest that targeting nonmalignant myeloid cells might serve as a novel immunotherapeutical strategy for CLL.


Asunto(s)
Ácido Clodrónico/farmacología , Regulación Leucémica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Monocitos/efectos de los fármacos , Animales , Antígenos Ly/genética , Antígenos Ly/inmunología , Antígeno B7-H1/genética , Antígeno B7-H1/inmunología , Quimiocina CXCL9/genética , Quimiocina CXCL9/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/patología , Modelos Animales de Enfermedad , Humanos , Inmunofenotipificación , Interleucina-10/genética , Interleucina-10/inmunología , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/patología , Macrófagos/inmunología , Macrófagos/patología , Ratones , Ratones Transgénicos , Monocitos/inmunología , Monocitos/patología , Cavidad Peritoneal/patología , Fenotipo , Receptores CCR2/genética , Receptores CCR2/inmunología , Transducción de Señal , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/patología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/patología , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
7.
Cell Death Differ ; 21(9): 1419-31, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24832469

RESUMEN

p53 loss of heterozygosity (p53LOH) is frequently observed in Li-Fraumeni syndrome (LFS) patients who carry a mutant (Mut) p53 germ-line mutation. Here, we focused on elucidating the link between p53LOH and tumor development in stem cells (SCs). Although adult mesenchymal stem cells (MSCs) robustly underwent p53LOH, p53LOH in induced embryonic pluripotent stem cells (iPSCs) was significantly attenuated. Only SCs that underwent p53LOH induced malignant tumors in mice. These results may explain why LFS patients develop normally, yet acquire tumors in adulthood. Surprisingly, an analysis of single-cell sub-clones of iPSCs, MSCs and ex vivo bone marrow (BM) progenitors revealed that p53LOH is a bi-directional process, which may result in either the loss of wild-type (WT) or Mut p53 allele. Interestingly, most BM progenitors underwent Mutp53LOH. Our results suggest that the bi-directional p53LOH process may function as a cell-fate checkpoint. The loss of Mutp53 may be regarded as a DNA repair event leading to genome stability. Indeed, gene expression analysis of the p53LOH process revealed upregulation of a specific chromatin remodeler and a burst of DNA repair genes. However, in the case of loss of WTp53, cells are endowed with uncontrolled growth that promotes cancer.


Asunto(s)
Alelos , Pérdida de Heterocigocidad , Células Madre/metabolismo , Proteína p53 Supresora de Tumor/genética , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Desnudos , Ratones SCID , Proteína p53 Supresora de Tumor/metabolismo
8.
Cell Death Differ ; 21(6): 929-40, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24531536

RESUMEN

Glioblastomas are highly aggressive brain tumours and are characterised by substantial cellular heterogeneity within a single tumour. A sub-population of glioblastoma stem-like cells (GSCs) that shares properties with neural precursor cells has been described, exhibiting resistance to therapy and therefore being considered responsible for the high recurrence rate in glioblastoma. To elucidate the underlying cellular processes we investigated the role of phosphatases in the GSC phenotype, using an in vitro phosphatome-wide RNA interference screen. We identified a set of genes, the knockdown of which induces a significant decrease in the glioma stem cell marker CD133, indicating a role in the glioblastoma stem-like phenotype. Among these genes, the ecto-nucleotidase ENPP1 (ectonucleotide pyrophosphatase/phosphodiesterase 1) was found to be highly expressed in GSCs compared with normal brain and neural stem cells. Knockdown of ENPP1 in cultured GSCs resulted in an overall downregulation of stem cell-associated genes, induction of differentiation into astrocytic cell lineage, impairment of sphere formation, in addition to increased cell death, accumulation of cells in G1/G0 cell cycle phase and sensitisation to chemotherapeutic treatment. Genome-wide gene expression analysis and nucleoside and nucleotide profiling revealed that knockdown of ENPP1 affects purine and pyrimidine metabolism, suggesting a link between ENPP1 expression and a balanced nucleoside-nucleotide pool in GSCs. The phenotypic changes in E-NPP1-deficient GSCs are assumed to be a consequence of decreased transcriptional function of E2F1. Together, these results reveal that E-NPP1, by acting upstream of E2F1, is indispensable for the maintenance of GSCs in vitro and hence required to keep GSCs in an undifferentiated, proliferative state.


Asunto(s)
Neoplasias Encefálicas/genética , Glioblastoma/genética , Células-Madre Neurales/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Pirofosfatasas/metabolismo , Antígeno AC133 , Antígenos CD/biosíntesis , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Puntos de Control del Ciclo Celular/genética , Diferenciación Celular/genética , Línea Celular Tumoral , Linaje de la Célula , Factor de Transcripción E2F1/metabolismo , Regulación Neoplásica de la Expresión Génica , Glioblastoma/metabolismo , Glioblastoma/patología , Glicoproteínas/biosíntesis , Humanos , Péptidos , Hidrolasas Diéster Fosfóricas/genética , Pirofosfatasas/genética
9.
Leukemia ; 28(6): 1289-98, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24280868

RESUMEN

Chronic lymphocytic leukemia (CLL) is an incurable malignancy of mature B cells. One of the major challenges in treatment of CLL is the achievement of a complete remission to prevent relapse of disease originating from cells within lymphoid tissues and subsequent chemoresistance. In search for novel drugs that target CLL cells in protective microenvironments, we performed a fungal extract screen using cocultures of primary CLL cells with bone marrow-derived stromal cells. A secondary metabolite produced by Penicillium aquamarinium was identified as Chaetoglobosin A (ChA), a member of the cytochalasan family that showed preferential induction of apoptosis in CLL cells, even under culture conditions that mimic lymphoid tissues. In vitro testing of 89 CLL cases revealed effective targeting of CLL cells by ChA, independent of bad prognosis characteristics, like 17p deletion or TP53 mutation. To provide insight into its mechanism of action, we showed that ChA targets filamentous actin in CLL cells and thereby induces cell-cycle arrest and inhibits membrane ruffling and cell migration. Our data further revealed that ChA prevents CLL cell activation and sensitizes them for treatment with PI3K and BTK inhibitors, suggesting this compound as a novel potential drug for CLL.


Asunto(s)
Apoptosis/efectos de los fármacos , Citocinesis/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Alcaloides Indólicos/farmacología , Leucemia Linfocítica Crónica de Células B/patología , Micotoxinas/farmacología , Células del Estroma/efectos de los fármacos , Actinas/metabolismo , Western Blotting , Estudios de Casos y Controles , Adhesión Celular/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Técnicas de Cocultivo , Citoesqueleto/metabolismo , Citometría de Flujo , Hongos/química , Voluntarios Sanos , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Células del Estroma/metabolismo , Células del Estroma/patología , Células Tumorales Cultivadas
10.
Leukemia ; 27(2): 353-61, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22810507

RESUMEN

Recently, the p53-miR-34a network has been identified to have an important role in tumorigenesis. As in acute myeloid leukemia with complex karyotype (CK-AML) TP53 alterations are the most common known molecular lesion, we further analyzed the p53-miR-34a axis in a large cohort of CK-AML with known TP53 status (TP53(altered), n=57; TP53(unaltered), n=31; altered indicates loss and/or mutation of TP53). Profiling microRNA (miRNA) expression delineated TP53 alteration-associated miRNA profiles, and identified miR-34a and miR-100 as the most significantly down- and upregulated miRNA, respectively. Moreover, we found a distinct miR-34a expression-linked gene expression profile enriched for genes belonging to p53-associated pathways, and implicated in cell cycle progression or apoptosis. Clinically, low miR-34a expression and TP53 alterations predicted for chemotherapy resistance and inferior outcome. Notably, in TP53(unaltered) CK-AML, high miR-34a expression predicted for inferior overall survival (OS), whereas in TP53(biallelic altered) CK-AML, high miR-34a expression pointed to better OS. Thus, detailed molecular profiling links impaired p53 to decreased miR-34a expression, but also identifies p53-independent miR-34a induction mechanisms as shown in TP53(biallelic altered) cell lines treated with 15-deoxy-Δ(12,14)-prostaglandin. An improved understanding of this mechanism might provide novel therapeutic options to restore miR-34a function and thereby induce cell cycle arrest and apoptosis in TP53(altered) CK-AML.


Asunto(s)
Biomarcadores de Tumor/genética , Aberraciones Cromosómicas , Leucemia Mieloide Aguda/genética , MicroARNs/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Adulto , Anciano , Células Cultivadas , Femenino , Perfilación de la Expresión Génica , Humanos , Cariotipificación , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tasa de Supervivencia , Adulto Joven
11.
Oncogene ; 31(27): 3235-43, 2012 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-22056879

RESUMEN

The concept of cancer stem-like cells (CSCs) has gained considerable attention in various solid tumors including glioblastoma, the most common primary brain tumor. This sub-population of tumor cells has been intensively investigated and their role in therapy resistance as well as tumor recurrence has been demonstrated. In that respect, development of therapeutic strategies that target CSCs (and possibly also the tumor bulk) appears a promising approach in patients suffering from primary brain tumors. In the present study, we utilized RNA interference (RNAi) to screen the complete human kinome and phosphatome (682 and 180 targets, respectively) in order to identify genes and pathways relevant for the survival of brain CSCs and thereby potential therapeutical targets for glioblastoma. We report of 46 putative candidates including known survival-related kinases and phosphatases. Interestingly, a number of genes identified are involved in metabolism, especially glycolysis, such as PDK1 and PKM2 and, most prominently PFKFB4. In vitro studies confirmed an essential role of PFKFB4 in the maintenance of brain CSCs. Furthermore, high PFKFB4 expression was associated with shorter survival of primary glioblastoma patients. Our findings support the importance of the glycolytic pathway in the maintenance of malignant glioma cells and brain CSCs and imply tumor metabolism as a promising therapeutic target in glioblastoma.


Asunto(s)
Glioma/genética , Glioma/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Fosfofructoquinasa-2/deficiencia , Fosfofructoquinasa-2/genética , Interferencia de ARN , Adenosina Trifosfato/biosíntesis , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Muerte Celular/genética , Supervivencia Celular/genética , Regulación Neoplásica de la Expresión Génica/genética , Glioma/diagnóstico , Glioma/metabolismo , Glucólisis/genética , Humanos , Isoenzimas/deficiencia , Isoenzimas/genética , Ácido Láctico/biosíntesis , Lentivirus/genética , Pronóstico , ARN Interferente Pequeño/genética
12.
Oncogene ; 31(29): 3409-18, 2012 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-22158042

RESUMEN

Deletions of chromosomal arms 1p and 19q are frequent in oligodendroglial tumours and linked to radio- and chemotherapy response as well as longer survival. The molecular mechanisms underlying this clinically important association are as yet unknown. Here, we studied the peroxiredoxin 1 (PRDX1) gene at 1p34.1 for promoter methylation and expression in primary gliomas and investigated its role in radio- and chemosensitivity of glioma cells in vitro. In total, we screened primary glioma tissues from 93 patients for methylation of the 5'-CpG island of PRDX1 by sodium bisulfite sequencing. PRDX1 mRNA and protein expression levels were determined in subsets of the tumours by quantitative PCR and western blot analysis, respectively. PRDX1 hypermethylation and reduced expression were frequently detected in oligodendroglial tumours and secondary glioblastomas, but not in primary glioblastomas. In oligodendroglial tumours, both PRDX1 hypermethylation and reduced mRNA expression were significantly associated with 1p/19q-deletion. Stable knockdown of PRDX1 by lentiviral transduction of short-hairpin (sh)RNA constructs significantly increased apoptosis and reduced cell viability of Hs683 glioma cells exposed to ionizing irradiation or temozolomide in vitro. Taken together, our findings indicate that epigenetic silencing of PRDX1 is frequent in 1p/19q-deleted oligodendroglial tumours and likely contributes to radio- and chemosensitivity of these tumours.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 1/genética , Glioma/patología , Oligodendroglía/metabolismo , Peroxirredoxinas/genética , Regiones Promotoras Genéticas/genética , Tolerancia a Radiación/genética , Adulto , Anciano , Apoptosis/efectos de los fármacos , Apoptosis/genética , Apoptosis/efectos de la radiación , Línea Celular Tumoral , Islas de CpG/genética , Metilación de ADN/efectos de los fármacos , Metilación de ADN/efectos de la radiación , Dacarbazina/análogos & derivados , Dacarbazina/farmacología , Regulación hacia Abajo/genética , Femenino , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/radioterapia , Humanos , Isocitrato Deshidrogenasa/genética , Masculino , Persona de Mediana Edad , Mutación , Oligodendroglía/efectos de los fármacos , Oligodendroglía/patología , Oligodendroglía/efectos de la radiación , Peroxirredoxinas/deficiencia , Regiones Promotoras Genéticas/efectos de los fármacos , Regiones Promotoras Genéticas/efectos de la radiación , Temozolomida , Adulto Joven
13.
Pathologe ; 31 Suppl 2: 211-4, 2010 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-20711583

RESUMEN

To establish precise diagnostic algorithms and standardised treatment of sarcomas in specialized centers, the interdisciplinary research group KoSar (sarcoma competence network) has been funded by German Cancer Aid. A sarcoma tissue repository and a diagnostic reference center have been set up, presently containing about 1000 accurately diagnosed sarcomas of different entities. Significant gene expression profiles for synovial sarcomas, leiomyosarcomas, myxoid liposarcomas and a small profile for myxofibrosarcomas as well as a new classification of angiosarcomas were defined. We systematically searched for activated signal transduction pathways in sarcoma cell lines and xenograft transplant models and candidate targets for molecular therapies were identified. Based on these results first clinical studies have been initiated by the German Interdisciplinary Sarcoma Study Group (GISG).


Asunto(s)
Sarcoma/genética , Sarcoma/patología , Animales , Investigación Biomédica , Línea Celular Tumoral , Conducta Cooperativa , Evaluación Preclínica de Medicamentos , Fibrosarcoma/diagnóstico , Fibrosarcoma/tratamiento farmacológico , Fibrosarcoma/genética , Fibrosarcoma/patología , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Comunicación Interdisciplinaria , Leiomiosarcoma/diagnóstico , Leiomiosarcoma/tratamiento farmacológico , Leiomiosarcoma/genética , Leiomiosarcoma/patología , Liposarcoma Mixoide/diagnóstico , Liposarcoma Mixoide/tratamiento farmacológico , Liposarcoma Mixoide/genética , Liposarcoma Mixoide/patología , Técnicas de Diagnóstico Molecular , Terapia Molecular Dirigida , Trasplante de Neoplasias , Sarcoma/diagnóstico , Sarcoma/tratamiento farmacológico , Sarcoma Sinovial/diagnóstico , Sarcoma Sinovial/tratamiento farmacológico , Sarcoma Sinovial/genética , Sarcoma Sinovial/patología , Transducción de Señal/genética
14.
Gut ; 59(9): 1236-44, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20479215

RESUMEN

BACKGROUND AND AIMS: Liver metastases are the leading cause of death in colorectal cancer. To gain better insight into the biology of metastasis and possibly identify new therapeutic targets we systematically investigated liver-metastasis-specific molecular aberrations. METHODS: Primary colorectal cancer (pCRC) and matched liver metastases (LMs) from the same patients were analysed by microarray-based comparative genomic hybridisation in 21 pairs and gene expression profiling in 18 pairs. Publicly available databases were used to confirm findings in independent datasets. RESULTS: Chromosome aberration patterns and expression profiles of pCRC and matched LMs were strikingly similar. Unsupervised cluster analysis of genomic data showed that 20/21 pairs were more similar to each other than to any other analysed tumour. A median of only 11 aberrations per patient was found to be different between pCRC and LM, and expression of only 16 genes was overall changed upon metastasis. One region on chromosome band 11p15.5 showed a characteristic gain in LMs in 6/21 patients. This gain could be confirmed in an independent dataset of LMs (n=50). Localised within this region, the growth factor IGF2 (p=0.003) and the intestinal stem cell specific transcription factor ASCL2 (p=0.029) were found to be over-expressed in affected LM. Several ASCL2 target genes were upregulated in this subgroup of LM, including the intestinal stem cell marker OLFM4 (p=0.013). The correlation between ASCL2 expression and four known direct transcriptional targets (LGR5, EPHB3, ETS2 and SOX9) could be confirmed in an independent expression dataset (n=50). CONCLUSIONS: With unprecedented resolution a striking conservation of genomic alterations was demonstrated in liver metastases, suggesting that metastasis typically occurs after the pCRC has fully matured. In addition, we characterised a subset of liver metastases with an ASCL2-related stem-cell signature likely to affect metastatic behaviour of tumour cells.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Cromosomas Humanos Par 11/genética , Neoplasias Colorrectales/metabolismo , Factor II del Crecimiento Similar a la Insulina/biosíntesis , Neoplasias Hepáticas/secundario , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Aberraciones Cromosómicas , Análisis por Conglomerados , Neoplasias Colorrectales/genética , Perfilación de la Expresión Génica/métodos , Genoma/genética , Humanos , Factor II del Crecimiento Similar a la Insulina/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
15.
Oncogene ; 29(23): 3411-22, 2010 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-20305691

RESUMEN

All-trans retinoic acid is a potent promoter of cellular differentiation processes, which is used in cancer therapy. Glioblastoma spheroid cultures are enriched in tumor-initiating cells, and provide a model to test new treatment options in vitro. We investigated the molecular mechanisms of response to exposure to differentiation-promoting conditions in such cultures. Microarray analyses of five independent cultures showed that after induction of differentiation, inhibitors of transforming growth factor-beta/bone morphogenetic protein, Wnt/beta-catenin and IGF signaling were upregulated, whereas expression of several microRNAs decreased, particularly that of the miR-17-92 cluster. In primary astrocytic gliomas (n=82), expression of several members of miR-17-92 was significantly higher relative to those of normal brain (n=8) and significantly increased with tumor grade progression (P<0.05). A high-level amplification of the miR-17-92 locus was detected in one glioblastoma specimen. Transfection of inhibitors of miR-17-92 induced increased apoptosis and decreased cell proliferation in glioblastoma spheroids. Mir-17-92 inhibition was also associated with increased messenger RNA (mRNA) and/or protein expression of CDKN1A, E2F1, PTEN and CTGF. The CTGF gene was shown to be a target of miR-17-92 in glioblastoma spheroids by luciferase reporter assays. Our results suggest that miR-17-92 and its target CTGF mediate effects of differentiation-promoting treatment on glioblastoma cells through multiple regulatory pathways.


Asunto(s)
Neoplasias Encefálicas/patología , Factor de Crecimiento del Tejido Conjuntivo/fisiología , Glioblastoma/patología , Esferoides Celulares/patología , Proteínas Reguladoras de la Apoptosis/genética , Proteína 11 Similar a Bcl2 , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Factor de Crecimiento del Tejido Conjuntivo/genética , Islas de CpG , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Metilación de ADN , Factor de Transcripción E2F1/genética , Humanos , Proteínas de la Membrana/genética , MicroARNs , Fosfohidrolasa PTEN/genética , Proteínas Proto-Oncogénicas/genética , Transducción de Señal
16.
Ann Oncol ; 21(8): 1636-1642, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20147743

RESUMEN

BACKGROUND: A single-nucleotide polymorphism (SNP) in the FGFR4 gene is associated with poor prognosis in solid tumors. A recent study presented the first evidence that FGFR4 Arg388 could predict resistance to adjuvant chemotherapy in breast cancer. The present study evaluates the potential of this SNP to predict response to neoadjuvant chemotherapy (NCT) for primary breast cancer (PBC). METHODS: As part of a randomized phase II trial, 257 patients received either doxorubicin-cyclophosphamide (AC) or doxorubicin-pemetrexed (AP) followed by docetaxel (Doc; Taxotere) as NCT for T2-4/N0-2/M0 PBC. FGFR4 genotype analyzed on germline DNA was correlated with clinicopathologic variables, clinical response, and pathological complete response (pCR) using univariate and multivariate analyses. RESULTS: Only axillary lymph node status was associated with FGFR4 Arg388 [odds ratio (OR) 1.82, P = 0.03]. Joint analysis of both treatment arms revealed a correlation of FGFR4 Arg388 with clinical response (OR 2.14, P = 0.03) but not with pCR. In the AC-Doc arm, however, FGFR4 Arg388 was a strong predictor of pCR in the multivariate analysis (OR 3.79, P = 0.03). A significant interaction between FGFR4 genotype and treatment (P = 0.01) was found, indicating a therapy-specific effect. CONCLUSION: We provide the evidence that FGFR4 388Arg is an independent predictor of pCR following AC-Doc as NCT in PBC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Arginina/genética , Neoplasias de la Mama/genética , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos/genética , Adulto , Anciano , Arginina/química , Secuencia de Bases , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Cartilla de ADN , Femenino , Genotipo , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Pronóstico , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos/química , Inducción de Remisión
17.
Leukemia ; 23(11): 2018-26, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19641524

RESUMEN

The two B-cell non-Hodgkin's lymphoma entities, chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), show recurrent chromosomal gains of 3q25-q29, 12q13-q14 and 18q21-q22. The pathomechanisms affected by these aberrations are not understood. The aim of this study was to identify genes, located within these gained regions, which control cell death and cell survival of MCL and CLL cancer cells. Blood samples collected from 18 patients with CLL and 6 patients with MCL, as well as 6 cell lines representing both malignancies were analyzed by gene expression profiling. By a comparison of genomic DNA and gene expression, 72 candidate genes were identified. We performed a limited RNA interference screening with these candidates to identify genes affecting cell survival. CCDC50 (coiled coil domain containing protein 50), SERPINI2 and SMARCC2 mediated a reduction of cell viability in primary CLL cells as well as in cell lines. Gene knockdown and a nuclear factor kappa B (NFkappaB) reporter gene assay revealed that CCDC50 is required for survival in MCL and CLL cells and controls NFkappaB signaling.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/genética , Leucemia Linfocítica Crónica de Células B/genética , Linfoma de Células del Manto/genética , ARN Interferente Pequeño , Células de la Médula Ósea/citología , Línea Celular Tumoral , Supervivencia Celular/fisiología , Proteínas de Unión al ADN , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Pruebas Genéticas , Genómica , Humanos , Péptidos y Proteínas de Señalización Intracelular/química , Riñón/citología , Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células del Manto/patología , FN-kappa B/metabolismo , Proteínas de Neoplasias/genética , Estructura Terciaria de Proteína , Serpinas/genética , Factores de Transcripción/genética , Transfección
18.
Am J Transplant ; 8(9): 1786-97, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18786225

RESUMEN

Mycophenolic acid (MPA) is a potent inhibitor of the inosine monophosphate dehydrogenase and used as an immunosuppressive drug in transplantation. MPA inhibits proliferation of T- and B-lymphocytes by guanosine depletion. Since fibroblasts rely on the de novo synthesis of guanosine nucleotides, it is assumed that MPA interacts with fibroblasts causing an increased frequency of wound healing problems. We show a downregulation of the cytoskeletal proteins vinculin, actin and tubulin in fibroblasts exposed to pharmacological doses of MPA using microarray technology, real-time polymerase chain reaction (PCR) and Western blot. This reduction in RNA and protein content is accompanied by a substantial rearrangement of the cytoskeleton in MPA-treated fibroblasts as documented by immunofluorescence. The dysfunctional fibroblast growth was validated by scratch test documenting impaired migrational capacity. In contrast, cell adhesion was increased in MPA-treated fibroblasts. The results of the cultured human fibroblasts were applied to skin biopsies of renal transplant recipients. Skin biopsies of patients treated with MPA expressed less vinculin, actin and tubulin as compared to control biopsies that could explain potential wound healing problems posttransplantation. The perspective of MPA-induced cytoskeletal dysfunction may go beyond wound healing disturbances and may have beneficial effects on (renal) allografts with respect to scarring.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Inmunosupresores/farmacología , Ácido Micofenólico/farmacología , Biopsia , Carbocianinas/metabolismo , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Procedimientos Quirúrgicos Dermatologicos , Relación Dosis-Respuesta a Droga , Fluoresceína-5-Isotiocianato/metabolismo , Colorantes Fluorescentes/metabolismo , Humanos , Inmunohistoquímica , Indoles/metabolismo , Faloidina/metabolismo , Rodaminas/metabolismo , Piel/citología
19.
Leukemia ; 21(12): 2463-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17728785

RESUMEN

Primary mediastinal B-cell lymphoma (PMBL) is an aggressive extranodal B-cell non-Hodgkin's lymphoma with specific clinical, histopathological and genomic features. To characterize further the genotype of PMBL, we analyzed 37 tumor samples and PMBL cell lines Med-B1 and Karpas1106P using array-based comparative genomic hybridization (matrix- or array-CGH) to a 2.8k genomic microarray. Due to a higher genomic resolution, we identified altered chromosomal regions in much higher frequencies compared with standard CGH: for example, +9p24 (68%), +2p15 (51%), +7q22 (32%), +9q34 (32%), +11q23 (18%), +12q (30%) and +18q21 (24%). Moreover, previously unknown small interstitial chromosomal low copy number alterations (for example, -6p21, -11q13.3) and a total of 19 DNA amplifications were identified by array-CGH. For 17 chromosomal localizations (10 gains and 7 losses), which were altered in more than 10% of the analyzed cases, we delineated minimal consensus regions based on genomic base pair positions. These regions and selected immunohistochemistries point to candidate genes that are discussed in the context of NF-kappaB transcription activation, human leukocyte antigen class I/II defects, impaired apoptosis and Janus kinase/signal transducer and activator of transcription (JAK/STAT) activation. Our data confirm the genomic uniqueness of this tumor and provide physically mapped genomic regions of interest for focused candidate gene analysis.


Asunto(s)
Aberraciones Cromosómicas , Secuencia de Consenso , Perfilación de la Expresión Génica/métodos , Linfoma de Células B/genética , Neoplasias del Mediastino/genética , Adulto , Apoptosis/genética , Línea Celular Tumoral/metabolismo , Deleción Cromosómica , Femenino , Amplificación de Genes , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Humanos , Quinasas Janus/genética , Quinasas Janus/metabolismo , Linfoma de Células B/patología , Masculino , Neoplasias del Mediastino/patología , Persona de Mediana Edad , FN-kappa B/metabolismo , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Factores de Transcripción STAT/genética , Factores de Transcripción STAT/metabolismo
20.
Ann Hematol ; 86(10): 733-9, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17653548

RESUMEN

As chromosomal instability may contribute to leukemogenesis in patients with congenital bone marrow failure (CBMF) disorders, it was the aim of this study to characterize chromosomally aberrant clones that arise during the clinical course of disease by means of R-banding and fluorescence in situ hybridization (FISH) analyses. In addition, multicolor-FISH and array-comparative genomic hybridization (CGH) were applied to characterize clonal chromosome aberrations in more detail. Between January 2004 and December 2005, we prospectively analyzed 90 samples of 73 patients with proven or suspected CBMF disorders enrolled in a German Study Network of CBMF diseases. Clonal aberrations could be identified in four of 73 patients examined. In one child with congenital thrombocytopenia, Jacobsen syndrome [del(11)(q24)c] was diagnosed, and thus a CBMF could be excluded. In a girl with Shwachman-Diamond syndrome, two independent clones, one with an isochromosome i(7)(q10), another with a complex aberrant karyotype, were identified. Simultaneously, transition into a myelodysplastic syndrome (MDS) occurred. The brother, who was also afflicted with Shwachman-Diamond syndrome, showed an isochromosome i(7q) as a single aberration. In the fourth patient with severe congenital neutropenia, an add(21)(q22) marker containing a low-level amplification of the AML1 gene was identified at the time point of transition into acute myelogenous leukemia (AML). In summary, we suggest that follow-up of patients with CBMF using chromosome and FISH analyses will be helpful for the early detection of transition into MDS or AML and thus should be an integral part of the clinical management of these patients.


Asunto(s)
Aberraciones Cromosómicas , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Síndrome de Deleción Distal 11q de Jacobsen/genética , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicos/genética , Neutropenia/genética , Adolescente , Adulto , Estudios de Casos y Controles , Transformación Celular Neoplásica/genética , Niño , Preescolar , Inestabilidad Cromosómica , Cromosomas Humanos/genética , Femenino , Estudios de Seguimiento , Humanos , Hibridación Fluorescente in Situ , Lactante , Recién Nacido , Síndrome de Deleción Distal 11q de Jacobsen/complicaciones , Leucemia Mieloide Aguda/etiología , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/congénito , Neutropenia/complicaciones , Neutropenia/congénito
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