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Query: UMLS:C0242379 (lung cancer)
 71,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Despite recent developments in the diagnosis and conventional treatment of non small cell lung cancer (NSCLC), the prognosis remains unsatisfactory, with 5-year survival rates of approximately 15% for all stages. To date, chemotherapy represents the standard treatment for advanced-non small lung cancer, but efficacy of currently available cytotoxic drugs is modest. Median survival does not exceed 8-10 months. New treatment strategies are needed and considerable hope has been placed in therapies that specifically target the molecular mechanisms of tumour growth. One molecular target of particular relevance to lung cancer pathogenesis is the epidermal growth factor receptor (EGFR), a cell membrane receptor tyrosine kinase. Several inhibitors of EGFR fuctinonal activation have been developed. Amon these, erlotinib (Tarceva) and gefitinib (Iressa) are two orally bioavailable, small molecule EGFR inhibitors of the tyrosine kinase enzymatic activity which prevent EGFR autophosphorylation and activation. In monotherapy, gefitinib and erlotinib have determinated a 10-20% response rate and a 30-50% symptom improvement in previously treated, chemotherapy refractory, advanced NSCLC patients. Furthermore, a randomized, placebo controlled, multicenter phase III study has shown a two months improvement in median survival with erlotinib in the second or third line treatment of metastatic NSCLC patients. We will summarize the clinical evidence on the anticancer activity of small molecule EGFR inhibitors.
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PMID:Small molecule epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in non-small cell lung cancer. 1660 81

Interstitial lung disease (ILD) refers to a diverse range of pulmonary fibrotic disorders and may be hard to accurately diagnose, as distinguishing it from other pulmonary diseases can be difficult. Estimations of the incidence in populations are confounded by the complexity of the different forms of the disorder. In addition, ILD is a comorbid disease of lung cancer and is seen after most forms of chemotherapy and radiotherapy for advanced lung cancer. Incidences of >or=10% have been reported; however, whatever the true incidence, both chemotherapy and radiotherapy enhance the risk of developing ILD. ILD has also been reported with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, including erlotinib (Tarceva, OSI-774) and gefitinib (IRESSA). In a large number of gefitinib-treated patients (n > 185,000) an incidence of approx 1% has been observed (approx 2% in Japan; 0.3% in the rest of the world). Nevertheless, as with other treatments for advanced non-small-cell lung cancer, the clinical benefit outweighs the risk of ILD. In this article, we review the data on ILD with EGFR inhibitors and other common lung cancer treatments.
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PMID:Interstitial lung disease in patients with non-small-cell lung cancer treated with epidermal growth factor receptor inhibitors. 1672 Sep 16

Anti-EGFR (epidermal growth factor receptor) therapies, including tyrosine kinase inhibitors (TKIs) and monoclonal antibodies, demonstrate activity in a variety of tumor types. While both inhibit the EGFR pathway, they act via different mechanisms. Monoclonal antibodies bind to the extracellular domain of EGFR, preventing ligand binding and interrupting the signaling cascade. Tyrosine kinase inhibitors bind to the intracellular domain of EGFR and inhibit the downstream effects of EGFR ligand binding. Both categories of agents have been evaluated in a variety of clinical settings and tumor types, including colorectal cancer, non-small-cell lung cancer (NSCLC), and squamous cell carcinoma of the head and neck (SCCHN). Phase II/III trials in patients with previously treated or untreated metastatic colorectal cancer, including those with documented refractory disease, demonstrate activity of the monoclonal antibody cetuximab (Erbitux) as a single agent or in combination with both irinotecan (Camptosar)- and oxaliplatin (Eloxatin)-based chemotherapy. Activity of cetuximab added to chemotherapy in patients who previously progressed on the same regimen suggests an ability to overcome chemotherapy resistance in some patients. In NSCLC, phase II trials of the TKI gefitinib (Iressa) plus combination chemotherapy showed impressive activity with considerable toxicity. Large, randomized, phase II trials (IDEAL 1 and 2) reported modest activity of gefitinib in NSCLC; however, phase III trials (INTACT 1 and 2)failed to demonstrate a benefit to adding gefitinib to chemotherapy. A similar trend was noted in trials of erlotinib (Tarceva) (TALENT and TRIBUTE). Phase II/III trials have shown promising activity of cetuximab in SCCHN, generating significantly improved survival in combination with radiotherapy over radiotherapy alone in locally advanced disease and significantly improved response rates in combination with chemotherapy over chemotherapy alone in recurrent/metastatic disease, with little enhancement of toxicity profiles. Limited clinical experience with TKIs in SCCHN suggests similar degrees of single-agent activity and dermatologic toxicities. Levels of EGFR expression and the presence of EGFR mutations correlate with responsiveness to TKI therapy, while it remains unclear whether a relationship exists between level of EGFR expression and cetuximab efficacy in colorectal cancer. Anti-EGFR therapies are good candidates for combination with other treatment modalities, including chemotherapy and radiotherapy, due to their tolerable safety profile and nonoverlapping toxicities. In addition, these agents represent important treatment options in patients ineligible for chemotherapy due to refractory or resistant disease. Ongoing trials continue to investigate both the monoclonal antibodies and TKIs in various treatment settings.
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PMID:Anti-EGFR therapies: clinical experience in colorectal, lung, and head and neck cancers. 1673 79

(1) There is no standard third-line treatment for locally advanced or metastatic non small-cell lung cancer. (2) Erlotinib, like gefitinib, inhibits the tyrosine kinase activity of the epidermal growth factor (EGF) receptor, and has been licensed for sale in the European Union. (3) A double-blind placebo-controlled trial involving 713 patients who had failed to respond to one or two previous chemotherapy regimens showed that erlotinib increased the median survival time by about 2 months (6.7 versus 4.7 months), without improving the quality of this survival. It is not possible to predict precisely which patients are most likely to respond to erlotinib. (4) In first-line treatment, erlotinib was no more effective than placebo as an adjunct to chemotherapy in 2 trials involving 1079 and 1172 patients. (5) The adverse effect profile of erlotinib seems similar to that of gefitinib, mainly consisting of gastrointestinal disturbances (especially diarrhoea: 54% of patients versus 18% on placebo), skin rash (75% versus 17%), and ocular disorders (conjunctivitis: 12% versus 2%). In the comparative trial of second- or third-line treatment, 0.8% of patients developed interstitial pneumonia. (6) Erlotinib, like gefitinib, is metabolized by the cytochrome P450 isoenzyme CYP3A4, potentially creating a high risk of interactions. (7) In practice, the limited benefit of erlotinib seems to be outweighed by its frequent adverse effects. Erlotinib should therefore only be used in clinical trials designed to identify subgroups of patients in whom the risk-benefit balance may be favourable.
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PMID:Erlotinib: new drug. Non small-cell lung cancer: like gefitinib, no established advantage. 1676 93

Erlotinib and gefitinib are small-molecule inhibitors of the epidermal growth factor tyrosine kinase. Erlotinib is approved for the treatment of locally advanced or metastatic non-small-cell lung cancer after failure of at least one prior chemotherapy regimen. Although it is active in unselected patients, clinical characteristics and tumor molecular markers associated with enhanced benefit have been identified. Notably, never-smoker status or a positive EGFR FISH test has been consistently predictive of greater erlotinib benefit. Other markers, such as EGFR mutations and EGFR protein expression, as determined by immunohistochemistry, and KRAS mutation status have not proven to be consistently associated with differential benefit.
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PMID:Predicting clinical benefit in non-small-cell lung cancer patients treated with epidermal growth factor tyrosine kinase inhibitors. 1686 87

We have developed a new assay for measuring epidermal growth factor receptor (EGFR) activation using the bioluminescence resonance energy transfer (BRET) technology, which directly measures the recruitment of signaling proteins to activated EGFR. Our results demonstrate that EGFR BRET assays precisely measure the pharmacology and signaling properties of EGFR expressed in human embryonic kidney 293T cells. EGFR BRET assays are highly sensitive to known EGFR ligands [pEC50 of epidermal growth factor (EGF)=10.1+/-0.09], consistent with previous pharmacological methods for measuring EGFR activation. We applied EGFR BRET assays to study the characteristics of somatic EGFR mutations that were recently identified in lung cancer. In agreement with recent reports, we detected constitutively active mutant EGFR isoforms, which predominantly signal through the phosphatidylinositol-3-kinase/Akt pathway. The EGFR inhibitors Iressa or Tarceva are severalfold more potent in inhibiting constitutive activity of mutant EGFR isoforms compared with wild-type EGFR. Notable, our results reveal that most of the mutant EGFR isoforms tested were significantly impaired in their response to EGF. The highest level of constitutive activity and nearly complete loss of epidermal growth factor responsiveness was detected in isoforms that carry the activating mutation L858R and the secondary resistance mutation T790M. In summary, our study reveals that somatic mutations in EGFR quantitatively differ in pharmacology and signaling properties, which suggest the possibility of differential clinical responsiveness to treatment with EGFR inhibitors. Furthermore, we demonstrate that the EGFR BRET assays are a useful tool to study the pharmacology of ligand-induced interaction between EGFR and signaling pathway-specifying adapter proteins.
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PMID:Pharmacology and signaling properties of epidermal growth factor receptor isoforms studied by bioluminescence resonance energy transfer. 1696 9

Erlotinib is a small-molecule tyrosine kinase inhibitor of the EGF receptor which has become an important oncological agent, used primarily in treating non-small-cell lung cancer. The most common side effects of this class of EGF receptor antagonists are cutaneous rashes. The severity of the skin rash seems to be correlated to clinical response and should be a motivating factor to continue therapy. We report a case of a patient who developed a follicular rash during therapy with erlotinib.
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PMID:Follicular rash during therapy with erlotinib (Tarceva). 1701 Jan 75

The receptor for epidermal growth factor (EGFR) is overexpressed in many cancers. One important signaling pathway regulated by EGFR is the phosphatidylinositol 3'-kinase (PI3K)-phosphoinositide-dependent kinase 1-Akt pathway. Activation of Akt leads to the stimulation of antiapoptotic pathways, promoting cell survival. Akt also regulates the mammalian target of rapamycin (mTOR)-S6K-S6 pathway to control cell growth in response to growth factors and nutrients. Recent reports have shown that the sensitivity of non-small-cell lung cancer cell lines to EGFR inhibitors such as erlotinib (Tarceva, OSI Pharmaceuticals) is dependent on inhibition of the phosphatidylinositol 3'-kinase-phosphoinositide-dependent kinase 1-Akt-mTOR pathway. There can be multiple inputs to this pathway as activity can be regulated by other receptors or upstream mutations. Therefore, inhibiting EGFR alone may not be sufficient for substantial inhibition of all tumor cells, highlighting the need for multipoint intervention. Herein, we sought to determine if rapamycin, an inhibitor of mTOR, could enhance erlotinib sensitivity for cell lines derived from a variety of tissue types (non-small-cell lung, pancreatic, colon, and breast). Erlotinib could inhibit extracellular signal-regulated kinase, Akt, and S6 only in cell lines that were the most sensitive. Rapamycin could fully inhibit S6 in all cell lines, but this was accompanied by activation of Akt phosphorylation. However, combination with erlotinib could down-modulate rapamycin-stimulated Akt activity. Therefore, in select cell lines, inhibition of both S6 and Akt was achieved only with the combination of erlotinib and rapamycin. This produced a synergistic effect on cell growth inhibition, observations that extended in vivo using xenograft models. These results suggest that combining rapamycin with erlotinib might be clinically useful to enhance response to erlotinib.
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PMID:Rapamycin synergizes with the epidermal growth factor receptor inhibitor erlotinib in non-small-cell lung, pancreatic, colon, and breast tumors. 1712 14

A leading oncologist has warned that some patients with cancer are ordering drugs on the internet because they cannot access them in the UK. Examples include bevacizumab (Avastin) for the treatment of advanced bowel cancer, and erlotinib (Tarceva) for the treatment of lung cancer. The World Health Organization and the Medicines and Healthcare products Regulatory Agency (MHRA) advise great caution about buying medicines over the internet and say it should not be done without a valid prescription. This article discusses the growth of online pharmacies, problems with regulation and the dangers of self-prescribing.
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PMID:Is the online drugs market putting patients at risk? 1714 24

Frequent overexpression of epidermal growth factor receptor (EGFR) in non-small-cell lung cancer (NSCLC) makes EGFR a new therapeutic target. Two specific EGFR tyrosine kinase inhibitors, gefitinib (ZD1839, Iressa) and erlotinib (OSI-774, Tarceva), have been developed and approved by the US Food and Drug Administration for second-line and third-line treatment of advanced NSCLC. Clinical trials have shown considerable variability in the response rate between different patients with NSCLC, which led to the discovery of somatic EGFR-activating mutations. This brief review summarises the discovery and functional consequences of the mutations, their clinicopathological features and significant implications in the treatment and prognosis of NSCLC.
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PMID:Somatic mutations of the epidermal growth factor receptor and non-small-cell lung cancer. 1715 92


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