14 documents found, page 1 of 2
A transcriptomic signature mediated by HOXA9 promotes human glioblastoma initia...
Pojo, Marta; Gonçalves, Céline S.; Magalhães, Ana Xavier; Oliveira, Ana Isabel; Gonçalves, Tiago; Correia, Sara; Rodrigues, Ana JoãoGlioblastoma is the most malignant brain tumor, exhibiting remarkable resistance to treatment. Here we investigated the oncogenic potential of HOXA9 in gliomagenesis, the molecular and cellular mechanisms by which HOXA9 renders glioblastoma more aggressive, and how HOXA9 affects response to chemotherapy and survival. The prognostic value of HOXA9 in glioblastoma patients was validated in two large datasets from...
Low frequency of TERT promoter mutations in gastrointestinal stromal tumors (GI...
Reis, R. M.; Campanella, Nathália C.; Celestino, Ricardo; Pestana, Ana; Scapulatempo-Neto, Cristovam; Oliveira, Antônio Talvane TorresSomatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene, mainly at positions c. − 124 and c. − 146 bp, are frequent in several human cancers; yet its presence in gastrointestinal stromal tumor (GIST) has not been reported to date. Herein, we searched for the presence and clinicopathological association of TERT promoter mutations in genomic DNA from 130 bona fide GISTs. We found ...
Analysis of a synchronous gliosarcoma and meningioma with long survival : a cas...
Linhares, Paulo; Martinho, Olga; Carvalho, Bruno; Castro, Lígia; Lopes, José M.; Vaz, Rui; Reis, R. M.BACKGROUND: The simultaneous occurrence of multiple intracranial neoplasms has been reported, especially in genetic familial syndromes and after cranial irradiation. In the absence of these etiologic factors, some reports showed simultaneous occurrence of glioblastoma and meningioma but the association between gliosarcoma and meningioma is unknown. CASE DESCRIPTION: We report a case of a 51-year-old woman with ...
Downregulation of RKIP is associated with poor outcome and malignant progressio...
Martinho, Olga; Granja, Sara Costa; Jaraquemada, Teresa; Caeiro, Cláudia; Gonçalves, Vera M.; Honavar, Mrinalini; Costa, Paulo; Damasceno, MargaridaMalignant gliomas are highly infiltrative and invasive tumors, which precludes the few treatment options available. Therefore, there is an urgent need to elucidate the molecular mechanisms underlying gliomas aggressive phenotype and poor prognosis. The Raf Kinase Inhibitory protein (RKIP), besides regulating important intracellular signaling cascades, was described to be associated with progression, metastasis ...
Impact of EGFR genetic variants on glioma risk and patient outcome
Costa, Bruno Marques; Pereira, Marta Viana; Fernandes, Ricardo; Costa, S.; Linhares, Paulo; Vaz, Rui; Pinheiro, Céline; Lima, Jorge; Soares, PaulaBACKGROUND: The epidermal growth factor receptor (EGFR) regulates important cellular processes and is frequently implicated in human tumors. Three EGFR polymorphisms have been described as having a transcriptional regulatory function: two single-nucleotide polymorphisms in the essential promoter region, -216G/T and -191C/A, and a polymorphic (CA)(n) microsatellite sequence in intron 1. We aimed to elucidate the...
Angiogenesis and breast cancer
Longatto, Adhemar; Lopes, José M.; Schmitt, Fernando C.Angiogenesis is an essential step for breast cancer progression and dissemination. The development of new blood vessels in cancer setting (angiogenesis) is conducted by numerous physiological and pathological stimuli, where the main stimulus is hypoxia. The knowledge of different molecular pathways regulating angiogenesis is constantly growing. An increased and complex scenario of angiogenesis is nowadays avail...
Prognostic value of MGMT promoter methylation in glioblastoma patients treated ...
Costa, Bruno Marques; Caeiro, Cláudia; Guimarães, Inês; Martinho, Olga; Jaraquemada, Teresa; Augusto, Isabel; Castro, Lígia; Osório, LígiaGlioblastoma (GBM) is the most common and aggressive primary brain tumor. The identification of novel molecular prognostic markers of GBM has recently been an area of great interest in neuro-oncology. The methylation status of the MGMT gene promoter is currently a promising molecular prognostic marker, but some controversial data have precluded its clinical use. We analyzed MGMT methylation by methylation-speci...
TP53 germline mutations in Portugal and genetic modifiers of age at cancer onset
Pinto, Carla; Veiga, Isabel; Pinheiro, Manuela; Peixoto, Ana; Pinto, Armando; Lopes, José M.; Reis, R. M.; Baptista, Manuela; Roque, LúciaThe Li-Fraumeni syndrome (LFS) is a rare, autosomal dominant disease caused by TP53 germline mutations. This study aimed to characterize the TP53 mutational spectrum in patients suspected to have LFS in Portugal and to evaluate the influence of the MDM2-SNP309 and TP53-72Arg variants and of telomere length on age of tumor onset. Probands were primarily selected using the classical LFS criteria (two cases) or th...
Analysis of EGFR Overexpression, EGFR gene amplification and the EGFRvIII Mutat...
Viana, Marta Pereira; Lopes, José M.; Little, Suzie; Milanezi, Fernanda; Basto, Diana; Pardal, Fernando; Jones, C.; Reis, R. M.Background: Patients with malignant gliomas do not respond to any current therapy. Epidermal growth factor receptor (EGFR) controls several oncogenic processes, being frequently up-regulated in gliomas due to overexpression, gene amplification and gene mutation. EGFR inhibitors are being tried in gliomas, yet the molecular determinants of therapeutic response are unclear. Materials and Methods: EGFR overexpress...
Molecular alterations of KIT oncogene in gliomas
Gomes, Ana L.; Reis-Filho, Jorge S.; Lopes, José M.; Martinho, Olga; Lambros, Maryou B. K.; Martins, Albino; Schmitt, Fernando; Pardal, FernandoGliomas are the most common and devastating primary brain tumours. Despite therapeutic advances, the majority of gliomas do not respond either to chemo or radiotherapy. KIT, a class III receptor tyrosine kinase (RTK), is frequently involved in tumourigenic processes. Currently, KIT constitutes an attractive therapeutic target. In the present study we assessed the frequency of KIT overexpression in gliomas and i...