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Query: UMLS:C0007097 (
carcinoma
)
152,788
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
With 15,000 new cases each year, bladder tumors are the second leading urological cancer in France, after prostate
carcinoma
. In spite of advances in surgical techniques and therapeutic protocols based on trans-urethral resection associated with additive treatment (immunotherapy or endovesical chemotherapy), the natural course of superficial bladder tumors remains marked by two risks: recurrence and progression. In spite of the impressive efforts developed by molecular biologists searching for new specific markers, none of the markers can currently replace histological features such as stage and grade. Although detection of microsatellite instability is a promising approach, numerous difficulties limit the use of these markers and prevent their application in routine practice. Let us hope that the new techniques for tissue analysis such as DNA or tissue-arrays developed for simultaneous analysis of hundreds or even thousands of tumors will allow identification and validation of biological and even therapeutic markers. Among the various biological markers, only the proliferative index given by the expression of Ki67, the expression of p53 and
EGFR
have been examined in comparative studies. Ki67 seems to be the best marker for progression, its expression and the interpretation of results being more reproducible than for p53.
...
PMID:[Bladder tumors and molecular markers. Current status and perspectives]. 1459 93
Epidermal growth factor (EGF) receptor (
EGFR
) is commonly amplified and/or mutated in high-grade gliomas. Abnormal signaling from this receptor tyrosine kinase is believed to contribute to the malignant phenotypes seen in these tumors. Highly specific small molecule inhibitors of this receptor tyrosine kinase have been developed and may potentially improve the treatment of these highly aggressive brain tumors. A glioma cell line overexpressing
EGFR
was developed to mimic the situation of a malignant glioma with amplified
EGFR
, and this line was used to characterize the response to specific
EGFR
inhibitors. Treatment of our in vitro glioma model with the
EGFR
kinase inhibitors ZD1839 (Iressa) or PD153035, synthetic anilinoquinazolines with high specificity for
EGFR
, resulted in significant suppression of
EGFR
autophosphorylation even with very low levels of drug. However, significantly higher levels of drug were required to fully inhibit signaling through the phosphatidylinositol 3'-kinase/AKT and mitogen-activated protein kinase kinase/extracellular signal-regulated kinase (ERK) pathways. Interestingly, not all downstream signaling pathways displayed this resistance to inhibition. EGF-dependent activation of signal transducers and activators of transcription-3 occurred at low doses of
EGFR
inhibitors. The uncoupling of
EGFR
autophosphorylation and signaling through AKT and ERK was not dependent on
EGFR
overexpression. In addition, although this response was seen in other glioma and the SK-BR3 breast cancer cell lines, it was not universally present. The SQ20B head and neck squamous
carcinoma
cell line demonstrated loss of EGF-dependent AKT and ERK activation even at low doses of inhibitor. Despite significant loss of EGF-dependent autophosphorylation, the inability of low levels of
EGFR
inhibitor to suppress some downstream signaling pathways in our model glioma cell line permitted continued EGF-responsive decreases in the expression of the cyclin-dependent kinase inhibitor p27KIP and EGF-dependent proliferation/cell cycle progression. Although the mechanism responsible for the differential sensitivity of the various signal transduction pathways to
EGFR
inhibitors remains unclear, signaling through erbB2 does not appear to be involved. The ability of certain tumor cells to maintain signaling through AKT and ERK under
EGFR
inhibition may represent a potential mechanism of resistance by which a tumor cell may escape the antiproliferative activity of this new class of drugs.
...
PMID:Resistance to small molecule inhibitors of epidermal growth factor receptor in malignant gliomas. 1461 44
The
EGFR
(epidermal growth factor receptor) plays a key role in the regulation of essential normal cellular processes and in the pathophysiology of hyperproliferative diseases such as cancer. Recent investigations have demonstrated that GPCRs (G-protein-coupled receptors) are able to utilize the
EGFR
as a downstream signalling partner in the generation of mitogenic signals. This cross-talk mechanism combines the broad diversity of GPCRs with the signalling capacities of the
EGFR
and has emerged as a general concept in a multitude of cell types. The molecular mechanisms of
EGFR
signal transactivation involve processing of transmembrane growth factor precursors by metalloproteases which have been recently identified as members of the ADAM (a disintegrin and metalloprotease) family of zinc-dependent proteases. Subsequently, the
EGFR
transmits signals to prominent downstream pathways, such as mitogen-activated protein kinases, the phosphoinositide 3-kinase/Akt pathway and modulation of ion channels. Analysis of GPCR-induced
EGFR
activation in more than 60 human
carcinoma
cell lines derived from different tissues has demonstrated the broad relevance of this signalling mechanism in cancer. Moreover,
EGFR
signal transactivation was linked to diverse biological processes in human cancer cells, such as cell proliferation, migration and anti-apoptosis. Together with investigations revealing the importance of this GPCR-
EGFR
cross-talk mechanism in cardiac hypertrophy, Helicobacter pylori -induced pathophysiological processes and cystic fibrosis, these findings support an important role for GPCR ligand-dependent
EGFR
signal transactivation in diverse pathophysiological disorders.
...
PMID:EGFR signal transactivation in cancer cells. 1464 Oct 26
The erbB receptor family is part of the receptor tyrosine kinase superfamily and consists of four members erbB. The erbB receptor family has been shown to play an important role in both the development of the normal breast and the pathogenesis and progression of breast cancer. Receptor overexpression has also been shown to be a negative prognostic indicator and to correlate with both tumor invasiveness and a lack of responsiveness to standard treatment, both chemotherapy and hormonotherapy. The targeting of
EGFR
mainly resides in two approaches: tyrosine kinase inhibition and monoclonal antibodies blocking ligand fixation. Many experimental data support the potential role of targeting
EGFR
in breast cancer. Particularly tyrosine kinase inhibitors demonstrates activity as single agent or in association with hormonotherapy, chemotherapy and trastuzumab. The association of Iressa with hormonotherapy points out that theses agents may prevent or differ hormonoresistance. Moreover studies in situ
carcinoma
suggest that tyrosine kinase inhibitors may play a role in chemoprevention. So, targeting
EGFR
may be indicated in a large spectrum of breast tumors from early to advanced stages, hormone negative or positive breast tumors. However the complexity of erbB network requires the targeting of multiple molecular sites within the network and the characterization of tumor profiles in order to optimally select patients for these therapies.
...
PMID:[Targeting epidermal growth factor receptor in cancer of the breast]. 1476 49
Mouse, chimeric, humanized and human monoclonal antibodies (MABs) are all in use for treatment of human cancer. Unconjugated antibodies have a complex mechanism of action, dependent on the nature of the target structure. Antibodies can activate the immune system (antibody-dependent cellular cytotoxicity [ADCC], complement-dependent cytotoxicity [CDC], induction of tumor immunity [idiotype network]). ADCC appears to be one of the most important immune effector functions. Antibodies may also induce apoptosis, cell cycle arrest, inhibition of cell proliferation as well as angiogenesis and metastatic spread. For most antibodies there is no clear dose-response relationship in vivo. The effect of antibodies can be enhanced by combination with chemotherapy and/or by agents which activate the immune system. The best therapeutic effect may be obtained if MABs are used early in the course of the disease. Rituximab (anti-CD20) was the first registered MAB for the therapy of follicular lymphoma. Impressive results have been seen in combination with CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisone) in follicular and high-grade lymphomas. In other non-Hodgkin's lymphoma subtypes, promising results are also seen in combination with chemotherapy. Trastuzumab (anti-Her2) is a breakthrough in the treatment of breast cancer in combination with chemotherapeutic agents. This antibody is also in clinical testing for adjuvant treatment. Alemtuzumab (anti-CD52) has shown impressive results both in refractory chronic lymphocytic leukemia and as up-front therapy. There are many other antibodies in late stages of testing for registration. Interesting MABs include cetuximab (anti-epidermal growth factor receptor [
EGFR
]), especially in combination with radiotherapy in head and neck cancer; ABX-EGF (anti-
EGFR
) in renal carcinoma; bevacizumab (anti-vascular endothelial growth factor) in several solid tumors. Antiepithelial cell adhesion molecule antibodies show promise in combination with chemotherapy in the adjuvant setting of colorectal
carcinoma
. It is estimated that about 20 antibodies will be in clinical use by the year 2010.
...
PMID:Monoclonal antibodies in human cancer. 1498 43
Inflammatory breast cancer (IBC) is a rare but very aggressive form of breast cancer. Its definition is based on clinical criteria, but a molecular definition could be useful when data are incomplete or features are missing. Recently, the identification of overexpression of E-cadherin in IBC has improved understanding of the molecular basis of this disease. Consequently, the aim of this study was to try to determine an immunophenotypic 'signature' of IBC. A series of 80 cases of IBC were compared with 552 non-IBC control cases and a model was elaborated to evaluate the probability of an inflammatory
carcinoma
being present in any clinical situation. Tissue microarrays (TMAs) were used to determine the immunohistochemical profile of eight proteins including E-cadherin,
EGFR
, oestrogen and progesterone receptor (ER and PR), MIB1, ERBB2, MUC1, and P53. All the parameters tested were differentially expressed between IBC and control cases in univariate analysis (p < 0.001). The five variables that were significantly associated with IBC in multivariate analysis were E-cadherin > or = 300 [HR = 5.64 (2.92-10.87)], ER negative [HR = 3.00 (1.67-5.51)], MIB1 > 20 [HR = 3.54 (1.87-6.71)], MUC1 cytoplasmic staining [HR = 2.72 (1.49-4.96)], and ERBB2 positive 2+ or 3+ [HR = 2.46 (1.26-4.78)]. The probability that a breast cancer with this full phenotype at diagnosis was an IBC was 90.5%. If any one of the five parameters was missing, this probability dropped to 75% and was less than 50% when one, two, or three parameters were present. The 5-year overall survival (OS) and 5-year disease-free survival (DFS) of patients with IBC were not significantly different from those of the non-IBC control group that expressed four or five parameters (nIBC-1), but this nIBC-1 control group had a significantly worse outcome than the non-IBC control group (nIBC-2) with only 0-3 parameters (p = 0.0049 for OS and p < 0.0001 for DFS). In conclusion, an immunophenotypic signature was suggested for IBC. This could help to determine the worst cases, independent of clinical criteria.
...
PMID:Immunophenotypic analysis of inflammatory breast cancers: identification of an 'inflammatory signature'. 1499 91
Genomic analyses aimed at the detection of high-level DNA amplifications were performed on 13 widely used pancreatic cancer cell lines and 6 pancreatic tumor specimens. For these analyses, array-based comparative genomic hybridization (Matrix-CGH) onto dedicated microarrays was used. In comparison with chromosomal CGH (eight amplifications), a >3-fold number of DNA amplifications was detected (n = 29). The most frequent amplifications mapped to 7p12.3 (three pancreatic cancer cell lines and three pancreatic tumor specimens), 8q24 (four pancreatic cancer cell lines and one pancreatic tumor specimen), 11q13 (three pancreatic cancer cell lines and three pancreatic tumor specimens), and 20q13 (four pancreatic cancer cell lines and three pancreatic tumor specimens). Genes contained in the consensus regions were MYC (8q24),
EGFR
(7p12.3), and FGF3 (11q13). In six of seven pancreatic cancer cell lines and pancreatic tumor specimens with 20q13 amplifications, the novel candidate gene NFAT C2, which plays a role in the activation of cytokines, was amplified. Other amplifications also affected genes for which a pathogenetic role in pancreatic
carcinoma
has not been described, such as BCL10 and BCL6, two members of the BCL family. A subset of amplified genes was checked for overexpression by means of real-time PCR, revealing the highest expression levels for BCL6 and BCL10. Thus, Matrix-CGH allows the detection of a high number of amplifications, resulting in the identification of novel candidate genes in pancreatic cancer.
...
PMID:Genomic DNA-chip hybridization reveals a higher incidence of genomic amplifications in pancreatic cancer than conventional comparative genomic hybridization and leads to the identification of novel candidate genes. 1523 51
Chemical transformation of the SV-40 immortalized bronchial epithelial cell line BEAS2-B induces alterations in molecules involved in cell cycle control, including up-regulation of
EGFR
and cyclin E [Oncogene 13 (1996) 1983; Clin Cancer Res 8 (2002) 54]. The finding that these changes also occur in vivo, in both pre-invasive and invasive lung cancer [Cancer Res 55 (1995) 1365; Cancer Res 59 (1999) 2470], proves this to be a suitable model to study lung carcinogenesis. The current study tested the hypothesis that chemical treatment of BEAS2-B with Cigarette Smoke Condensate (CSC) may affect levels of gene products involved in cell adhesion and tissue remodeling. To this end, we studied the extent of changes in osteonectin (ON) protein levels induced in BEAS 2 B-cells by CSC treatment and its timing to changes occurring in the anchorage independent cloning efficiency. ON, a multimodular protein component of the extra-cellular matrix, has been implicated in tissue remodeling occurring in neoplastic and non-neoplastic conditions, but its role in lung carcinogenesis is incompletely characterized. To validate the in vitro findings, as in our previous reports, we studied resected lung tissue, to assess whether ON expression in neoplastic lung tissue differs from normal, and to determine its cellular localization. We found that CSC treatment of BEAS2-B cells results in a 7-16-fold increase in ON protein levels, that is associated with increased colony forming efficiency. ON is absent in normal lung; in contrast it is present in the majority (39/52) of non-small cell lung cancer (NSCLC). Here, its expression is restricted to peritumoral fibroblasts in squamous cell carcinoma and adenocarcinoma. In contrast, it is localized to tumor cells in pulmonary sarcomatoid
carcinoma
(8/10). Thus, up-regulated ON is linked in vitro to cell transformation and in vivo, it is frequently expressed in tumor-associated fibrosis, compatible with its proposed role in tissue remodelling. Increased ON expression by tumor cells appears to represent a marker of sarcomatoid NSCLC.
...
PMID:Increased osteonectin expression is associated with malignant transformation and tumor associated fibrosis in the lung. 1524 91
The role of biomarkers in disease prognosis continues to be an important investigation in many cancer studies. In order for these biomarkers to have practical application in clinical decision making regarding patient treatment and follow-up, it is common to dichotomize patients into those with low vs. high expression levels. In this study, receiver operating characteristic (ROC) curves, area under the curve (AUC) of the ROC, sensitivity, specificity, as well as likelihood ratios were calculated to determine levels of growth factor biomarkers that best differentiate lung cancer cases versus control subjects. Selected cut-off points for p185(erbB-2) and
EGFR
membrane appear to have good discriminating power to differentiate control tissues versus uninvolved tissues from patients with lung cancer (AUC = 89% and 90%, respectively); while AUC increased to at least 90% for selected cut-off points for p185(erbB-2) membrane,
EGFR
membrane, and FASE when comparing between control versus
carcinoma
tissues from lung cancer cases. Using data from control subjects compared to patients with lung cancer, we presented a simple and intuitive approach to determine dichotomized levels of biomarkers and validated the value of these biomarkers as surrogate endpoints for cancer outcome.
...
PMID:Receiver operating characteristic (ROC) to determine cut-off points of biomarkers in lung cancer patients. 1525 28
Human malignant tumors, such as non-small lung, breast, ovarian, head and neck, prostate, stomach and colorectal cancers express a number of growth factor receptors (e.g.
EGFR
or
EGFR
family members) that are regulated by tumor hypoxia and contribute to tumor growth and failure of cytotoxic therapy. Paclitaxel and docetaxel are indispensable substances in the treatment of these tumors. Despite the active clinical use of taxanes, little is known about their cytotoxic activity under hypoxia. The aim of the present work was to compare the cytotoxic effect of taxanes, paclitaxel and docetaxel on the
EGFR
-expressing
carcinoma
cell lines A431, MDA-MB-231 and NCI-H358 under normoxic and hypoxic conditions. The two taxanes caused different cell cycle distribution and varying aneuploid cell formation under hypoxia.
EGFR
-overexpressing
carcinoma
cells showed hypoxia to severely affect the cytotoxicity of paclitaxel, whereas docetaxel preserved its tumor cell-killing activity even at lowest concentrations (0.5 nM), as was observed for both taxanes under normoxia.
...
PMID:Effects of paclitaxel and docetaxel on EGFR-expressing human carcinoma cells under normoxic versus hypoxic conditions in vitro. 1533 13
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