Search results for "Oncogene"
showing 10 items of 1005 documents
Abstract LB-017: HSP110 sustains aberrant NFkB signaling in activated B-cell diffuse large B-cell lymphoma through MyD88 stabilization
2017
Abstract Diffuse large B cell lymphoma (DLBCL) is an aggressive lymphoproliferative disorder of B lymphocytes accounting for 30 % of adult Non Hodgkin Lymphoma (NHL). Among DLBCL, Activated B Cell - DLBCL (ABC-DLBCL) is the most aggressive form and has a poor prognosis. Heat-shock proteins (HSPs) are molecular chaperons highly expressed in cancer cells and implicated in resistance to radio- and chemotherapy. Therefore, HSPs are envisioned as therapeutic targets in many cancers. Among the different HSPs, HSP110 has been recently identified as a pro-survival factor in germinal center-derived DLBCL (GC-DLBCL), through stabilization of the GC-DLBCL oncogene Bcl-6. Here, we have explored if HSP1…
In the literature: February 2020.
2020
The phosphatidylinositol-3-kinase (PI3K)/Akt and the mammalian target of rapamycin (mTOR) signaling pathways is one of the most frequently deregulated pathways in human cancers. This pathway controls multiple cellular processes, including metabolism, motility, proliferation, growth and survival. It can be aberrantly activated through multiple mechanisms, including diverse genomic alterations involving oncogenes and tumour suppressor genes.1 These alterations offer opportunities for therapeutic targeting of the pathway. PI3Kα protein complex is composed of regulatory (p85α) and catalytic (p110α) subunits. Pik3ca codes for p110α, which is the most frequently mutated oncogene across different …
PO-298 MYC favours the onset of tumour initiating cells by inducing epigenetic reprogramming of mammary epithelial cells towards a stem cell-like sta…
2018
ABSTRACT Introduction Breast cancer consists of highly heterogenous tumours whose cell of origin resulted difficult to be defined. Recent findings highlighted the possibility that tumor-initiating cells (TICs) may arise from dedifferentiation of lineage-committed cells, by reactivation of multipotency in response to oncogenic insults. MYC is the most frequently amplified oncogene in breast cancer and the activation of MYC pathway has been associated with the basal-like subtype, which is characterised by poor survival and lack of a specific therapeutic strategy. Although MYC has been considered a driver oncogene in breast cancer, its mechanism of action in tumour initiation has been poorly a…
Broad-spectrum Cross-resistance to Anticancer Drugs Mediated by Epidermal Growth Factor Receptor
2019
BACKGROUND The oncogenic role of epidermal growth factor receptor (EGFR) has been intensively studied. However, its emerging role in drug resistance has not been fully addressed. MATERIALS AND METHODS This study systematically investigated the correlation of mRNA and protein expression of EGFR, as well as gene amplification and mutations with the log-transformed half-maximal inhibitory concentration (log10IC50) values obtained from the NCI panel of 60 human tumor cell lines against 83 standard anticancer agents and the top 10 natural cytotoxic products previously screened by us. RESULTS EGFR protein expression, rather than other measurements, was most frequently associated with drug respons…
Uncommon Synchronous Association between Ovarian Carcinoma and Gastrointestinal Stromal Tumor: A Case Study and Literature Review
2013
Background The association of gastrointestinal stromal tumors (GIST) and other cancers is well known, but its synchronous occurrence with gynecological malignancies is very uncommon. Usually, the diagnosis is accidentally established. We describe a patient with GIST and concurrent ovarian cancer and discuss the clinical implications of this finding. Case report A 64-year-old woman with a prior diagnosis of ovarian cancer developed a second recurrence after having undergone two operations and adjuvant chemotherapy. While tumor debulking was performed, a small, nonsuspicious lesion was removed from the greater curvature of the stomach. Histology revealed a GIST. Conclusion The association of …
Mast Cells Infiltrating Inflamed or Transformed Gut Alternatively Sustain Mucosal Healing or Tumor Growth.
2015
Abstract Mast cells (MC) are immune cells located next to the intestinal epithelium with regulatory function in maintaining the homeostasis of the mucosal barrier. We have investigated MC activities in colon inflammation and cancer in mice either wild-type (WT) or MC-deficient (KitW-sh) reconstituted or not with bone marrow-derived MCs. Colitis was chemically induced with dextran sodium sulfate (DSS). Tumors were induced by administering azoxymethane (AOM) intraperitoneally before DSS. Following DSS withdrawal, KitW-sh mice showed reduced weight gain and impaired tissue repair compared with their WT littermates or KitW-sh mice reconstituted with bone marrow-derived MCs. MCs were localized i…
Role of the Ha-ras gene in the malignant transformation of rat liver oval cells.
1997
We have shown that the oval cell line OCICDE 22 can be transformed by the highly carcinogenic fiord-region diol epoxides of benzo[c]phenanthrene. Mutational activation of the ras proto-oncogene family has been proposed to be a critical event in the formation of tumors induced by polycyclic aromatic hydrocarbons. Therefore, we investigated whether in the earlier transformed OCICDE 22 cells any point mutations were detected in the ras proto-oncogene. The results indicate that the malignant transformation of OCICDE 22 cells by the 4 stereoisomeric benzo[c]phenan-threne diol epoxides in vitro is independent of activation of the Ha-ras proto-oncogene. In addition, Northern and Western blot analy…
EWS/FLI-1 rearrangement in small round cell sarcomas of bone and soft tissue detected by reverse transcriptase polymerase chain reaction amplificatio…
1994
Recent cloning of the t(11;22) region has led to the detection of a number of sequences involved in the breakpoints by substituting a sequence which encodes a putative RNA binding domain for that of the DNA binding domain of the human homologue of murine FLI-1. Several tumours display consistent translocation at t(11;22) (q24;q12), a finding that suggests these fusion transcripts could be expressed and detected by reverse transcriptase polymerase chain reaction amplification. To date, only a small number of Ewing's sarcomas (Es) and peripheral neuroectodermal tumours (pPNET) of bone have been tested with this novel molecular biology approach. In this study, we confirmed the presence of the …
Comparative study of human colonic tumor-derived endothelial cells (HCTEC) and normal colonic microvascular endothelial cells (HCMEC): Hypoxia-induce…
2009
Colorectal carcinoma growth and progression is dependent on the vasculature of the tumor microenvironment. Tumor-derived endothelial cells differ functionally from their normal counterpart. For this reason we isolated microvascular endothelial cells from human colon cancer tissue (HCTEC) and compared them with endothelial cells from normal colonic tissue (HCMEC) of the same donor. Since hypoxia is a universal hallmark of carcinomas, we examined its effects on HCTEC of five patients in comparison with the corresponding HCMEC, with respect to the secretion of the soluble form of the two important vascular endothelial growth factor (VEGF) receptors, VEGFR-1 and -2. After dissociation by dispas…
Loss of E-cadherin in the vicinity of necrosis in colorectal carcinomas: Association with NFκB expression
2007
The transcription factor NFkappaB regulates the expression of several tumor-related molecules associated with tumor progression and metastasis. However, the precise mechanisms by which its activation mediates these processes in diverse tumors are unknown. In this study we determined the expression of NFkappaB in various colorectal carcinoma cell lines, in a series of 90 non-metastatic and metastatic colorectal tumors and in an in vitro 3D-spheroid model of HT-29 cells simulating morphological hallmark of these adenocarcinomas, namely neoplastic glandular nests around a necrotic center. We show that the inactive cytoplasmic NFkappaB form is evidently up-regulated in the tumor epithelium, esp…