Platinum-based doublet chemotherapy remains the cornerstone of therapy in the first-line setting in advanced non-small-cell lung cancer (NSCLC) for patients with good performance status. However, this paradigm has recently been challenged by the results of a study that showed a survival benefit with the addition of bevacizumab to carboplatin and paclitaxel in bevacizumab-eligible patients and by the superior efficacy of gefitinib and erlotinib compared to chemotherapy in epidermal growth factor receptor (EGFR) gene mutation-positive tumors (mainly adenocarcinomas). In addition, histology has been recently recognized as a potential predictive factor in advanced NSCLC patients treated with chemotherapy. Prospective data from a preplanned subgroup analysis of a phase III study and retrospective reviews consistently reported a significant interaction between treatment by histology and response/survival in nonsquamous NSCLCs treated with pemetrexed, compared to squamous cell carcinoma (SCC). Thymidylate synthase, the main target of pemetrexed, was found to be differentially expressed among the histotypes of lung cancer, being lower in adenocarcinoma and higher in SCC and small-cell lung cancer. Thus, the availability of adequate amounts of tissue from biopsies to allow accurate pathologic subclassifications at diagnosis will be critical to help the oncologist select the most appropriate chemotherapy regimen as we move toward an individualized molecularly based approach. less...

Gefitinib is an orally active, selective epidermal growth factor receptor-tyrosine kinase inhibitor. The present study was aimed at evaluating the antitumor activity of gefitinib alone or in combination with other antitumor agents. Gefitinib showed higher cytotoxicity against five human tumor cell lines (HSC-2, HSC-3, HSC-4, T98G and U87MG) than against three human normal oral cells (gingival fibroblast HGF, pulp cell HPC and periodontal ligament fibroblast HPLF). Gefitinib showed little or no growth stimulation effects at lower concentrations (so-called hormetic effect). Non-cytotoxic concentration of gefitinib effectively enhanced the cytotoxicity of docetaxel against HSC-2 and T98G cell, but failed to enhance the cytotoxicity of other antitumor agents (mitoxantrone, doxorubicin, methotrexate, cisplatin, sodium ascorbate, sodium fluoride) or herbal extracts (Drynaria baronii, Angelica sinensis and Cornus officinalis Sieb. et Zucc). Gefitinib alone and combined with docetaxel induced internucleosomal DNA fragmentation and caspase-3 activation in human promyelocytic leukemia HL-60 cells, but not in HSC-2 or T98G cells. Combination treatment with gefitinib and docetaxel induced the formation of acidic organelles (stained with acridine orange) and mitochondrial shrinkage, vacuolization and production of autophagosome and the loss of cell surface microvilli, without destruction of cell surface and nuclear membranes in HSC-2 and T98G cells (demonstrated by transmission electron microscopy), suggesting the induction of autophagy in HSC-2 and T98G cells. less...

Glioblastoma is the most frequent and devastating primary malignant brain tumor in adults. Surgery followed by standard radiotherapy with concomitant and adjuvant chemotherapy with temozolomide is the standard of care in patients with glioblastoma, however the prognosis remains poor with a median survival in the range of 12-15 months. Common genetic abnormalities in glioblastoma are associated with aberrant activation or suppression of cellular signal transduction pathways and resistance to radiation and chemotherapy. Special attention has been focused on targets such as epidermal growth factor receptor, vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and on pathways such as the phosphatidylinositol-3kinase/Akt/mammalian target of rapamycin and Ras/Raf/mitogen-activated protein-kinase pathways. Several signal transduction inhibitors have been examined in preclinical and clinical malignant glioma trials, including antiangiogenic agents (bevacizumab, enzastaurin), and inhibitors of epidermal growth factor receptor tyrosine kinase (gefitinib and erlotinib), mammalian target of rapamycin (temsirolimus, everolimus) and integrin (cilengitide). Although preliminary clinical results of the use of targeted agents have not translated into significantly better survival, more recent phase II trials are exploring the combination of multitargeted drugs with cytotoxic chemotherapy and radiotherapy in order to overcome the resistance of tumors to single-agent targeted therapies. This review summarizes the current results with cytotoxic and targeted molecular agents in glioblastoma and the development of new chemoradiation strategies under evaluation to increase their effectiveness. less...

BACKGROUND: Pemetrexed is one of the standard second-line therapies in advanced non-small cell lung cancer (NSCLC). Currently, there are no standard cytotoxic treatments beyond second-line therapy. We evaluated the efficacy and safety of pemetrexed as a salvage regimen in heavily pretreated NSCLC patients. We also analyzed thymidylate synthase (TS) expression in tumor tissues to determine whether TS expression is correlated with the clinical efficacy of pemetrexed. METHODS: One hundred and ten NSCLC patients who received pemetrexed as third- or fourth-line therapy at the Samsung Medical Center between June 2006 and June 2008 were retrospectively reviewed. TS expression was analyzed by immunohistochemical staining in 55 NSCLC tissue specimens. The relationships between TS expression and clinicopathological factors were evaluated. Univariate and multivariate analyses were performed to define the predictive factors and prognostic significances. RESULTS: The median age of patients in this study was 59 years (range: 24-84), 50.9% were men, and 27 (24.6%) were smokers or previous smokers. Sixty-five patients (59.1%) received pemetrexed as third-line treatment, and 95 (86.4%) had non-squamous cell carcinoma. Platinum-based chemotherapy (84.6%) was the most common first-line therapy, and EGFR TKIs [erlotinib (17.3%) or gefitinib (43.6%)] were a common second-line therapy. The median time from date of diagnosis to the date of the first pemetrexed treatment was 12.8 months (range: 1.8-62.2 months) and the median number of pemetrexed treatments was 4 (range 1-22). Eighteen patients achieved PR (16.3%), 41 patients SD (37.3%), and 43 patients PD (39.1%), with a disease control rate of 53.6%. The median follow-up duration was 16.1 months, the median progression-free survival (PFS) was 3.2 months (95% CI: 1.9-4.5 months), and the median overall survival (OS) was 11.6 months (95% CI: 9.0-14.1 months). Male gender was the only independent variable for poor PFS (HR=1.673, 95% CI: 1.103-2.535), with poor performance status (HR=2.454, 95% CI: 1.405-4.287) and history of smoking (HR=1.856, 95% CI: 1.087-3.168) being independent adverse factors for OS. Thirteen of 55 tumor tissues (23.6%) showed TS expression; however, there were no significant correlations between TS expression and the clinicopathological factors. CONCLUSION: Pemetrexed was suggested as a third- or fourth-line therapy due to its favorable efficacy and tolerable toxicity. Further studies are warranted to define the adequate sequence of salvage treatments, especially in patients with adenocarcinoma lung cancer. less...

AIM: Cediranib is a highly potent inhibitor of vascular endothelial growth factor receptor (VEGFR) signalling. Preclinical and clinical data suggest that inhibition of the VEGFR and epidermal growth factor receptor (EGFR) pathways may be synergistic. Combination treatment with cediranib and gefitinib, an EGFR signalling inhibitor, was evaluated in patients with advanced solid tumours. PATIENTS AND METHODS: Ninety patients received treatment in this four-part, open-label study (NCT00502060). The patients received once-daily oral doses of cediranib (20-45mg) and gefitinib 250mg (part A1; n=16) or 500mg (part B1; n=44). A cohort expansion phase investigated the potential pharmacokinetic interaction of cediranib 30mg with gefitinib 250mg (part A2; n=15) or 500mg (part B2; n=15). The primary objective was to assess the safety and tolerability of cediranib with gefitinib. Secondary assessments included pharmacokinetics, efficacy and pharmacodynamics. RESULTS: Combination treatment was generally well tolerated; the protocol-defined maximum-tolerated dose of cediranib was 30mg/day with gefitinib 250mg/day (part A1) and cediranib 45mg/day was the maximum dose investigated with gefitinib 500mg/day (part B1). The most common adverse events were diarrhoea (84 [93%]), anorexia (63 [70%]) and fatigue (60 [67%]). Cediranib pharmacokinetic parameters were not substantially different when given alone or in combination with gefitinib. Gefitinib pharmacokinetic parameters were similar to those seen previously with gefitinib monotherapy. Efficacy results included eight (9%) confirmed partial responses (6 renal; 1 lung; 1 osteosarcoma) and 38 (42%) patients with stable disease. Pharmacodynamic assessments demonstrated changes in levels of VEGF and soluble VEGFR-2 following treatment CONCLUSIONS: Combination treatment was generally well tolerated and showed encouraging antitumour activity in patients with advanced solid tumours. These results merit further exploration. less...

The epidermal growth factor (EGF) family of receptor tyrosine kinases consists of four members: EGFR (HER1/ErbB1), HER2/neu (ErbB2), HER3 (ErbB3) and HER4 (ErbB4). Receptor activation via ligand binding leads to downstream signaling that influence cell proliferation, angiogenesis, invasion and metastasis. Aberrant expression or activity of EGFR and HER2 have been strongly linked to the etiology of several human epithelial cancers including but not limited to head and neck squamous cell carcinoma (HNSCC), non-small cell lung cancer (NSCLC), colorectal cancer (CRC), and breast cancer. With this, intense efforts have been made to inhibit the activity of the EGFR and HER2 by designing antibodies against the ligand binding domains (cetuximab, panitumumab and trastuzumab) or small molecules against the tyrosine kinase domains (erlotinib, gefitinib, and lapatinib). Both approaches have shown considerable clinical promise. However, increasing evidence suggests that the majority of patients do not respond to these therapies, and those who show initial response ultimately become refractory to treatment. While mechanisms of resistance to tyrosine kinase inhibitors have been extensively studied, resistance to monoclonal antibodies is less well understood, both in the laboratory and in the clinical setting. In this review, we discuss resistance to antibody-based therapies against the EGFR and HER2, similarities between these resistance profiles, and strategies to overcome resistance to HER family targeting monoclonal antibody therapy. less...

BACKGROUND:: We investigated the risk of central nervous system (CNS) failure after clinical benefit with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in Korean patients with nonsmall-cell lung cancer (NSCLC) METHODS:: We retrospectively evaluated the pattern of disease progression of 287 advanced NSCLC patients who were treated with gefitinib or erlotinib. Patients whose best tumor response was complete response, partial response, or stable disease (>/=90 days) were classified into the group receiving clinical benefit with these drugs. RESULTS:: The clinical benefit group had a higher incidence of CNS failure as an initial progression, compared with the non-clinical benefit group (26% vs 4%; P < .001). Isolated CNS failure was also more frequent in the clinical benefit group than in the non-clinical benefit group (13% vs 1%; P < .001). In a multivariate analysis, clinical benefit with EGFR-TKIs significantly increased the risk of isolated CNS failure, with an adjusted hazard ratio of 10.9 (95% confidence interval [CI], 1.4-29.1, P = .01). In patients with isolated CNS failure, the median time from initial intracranial failure to extracranial failure was 9.9 months (95% CI, 1.9-21.9 months) and to death was 12.9 months (95% CI, 3.3-22.5 months). CONCLUSIONS:: The CNS was frequently the initial failure site after clinical benefit with EGFR-TKIs in Korean NSCLC patients. Patients with isolated CNS failure showed durable extracranial control after cranial progression. A role for close surveillance of the CNS during EGFR-TKI treatment or prophylactic measures appears worthy of further study in these patients. Cancer 2010. (c) 2010 American Cancer Society. less...

CONTEXT: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors are molecular-targeted drugs that are innovatively effective for non-small cell lung carcinomas with EGFR mutations. Epidermal growth factor receptor is a transmembrane receptor forming dimers on ligand binding. These then stimulate signals by activating receptor autophosphorylation through tyrosine kinase activity. Autophosphorylation triggers intracellular pathways facilitating malignant conversion. The most clinically advanced EGFR inhibition strategies include small-molecule inhibition of the intracellular tyrosine kinase domain (gefitinib and erlotinib) and monoclonal antibody-mediated blockade of the extracellular ligand-binding domain (cetuximab). Lung cancers with EGFR mutations are prevalent among patients who are female, of Asian ethnicity, and nonsmokers; thus, they can obtain benefit from EGFR tyrosine kinase inhibitors. OBJECTIVE: To survey histopathologic findings and examine correlations with EGFR mutations. We mainly focused on component cell types (hobnail, columnar, and polygonal) and presence or absence of bronchioloalveolar carcinoma elements and a micropapillary pattern. Although EGFR mutations can be detected by various methods, including polymerase chain reaction-Invader assay or direct sequencing, these are inconvenient. DATA SOURCES: Review of the published literature. CONCLUSION: Detailed pathologic examination showed significant genotype-phenotype correlations between EGFR mutations and presence of a bronchioloalveolar carcinoma component, a micropapillary pattern, and the hobnail cell type. We conclude that these characteristic histologic features are good predictors of EGFR mutations, and patients with these features might be good candidates for and could benefit from therapy with EGFR tyrosine kinase inhibitors. less...

OBJECTIVE: To retrospectively evaluate the efficacy and safety of gefitinib in elderly patients with advanced non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor mutations. METHODS AND PATIENTS: Nine patients aged 70 years or older who had advanced NSCLC with mutations of the epidermal growth factor receptor gene were treated with gefitinib, 250 mg daily. Clinical data, types of epidermal growth factor receptor mutations, efficacy and toxicity of gefitinib were evaluated in these patients. Tumor responses were assessed by computed tomography scan using the Response Evaluation Criteria in Solid Tumors. RESULTS: Six patients showed a partial response, and the other three exhibited stable disease. The overall response rate was 66.7%. The median progression-free survival was 396 days, whereas the median over all survival was 523 days. No serious toxicities were observed. CONCLUSION: Gefitinib is very efficacious and safe for elderly patients with adenocarcinoma of the lung harboring an EGFR tyrosine kinase mutation. The present data support the use of gefitinib in this particular subgroup. less...

Cytotoxic chemotherapy offers a modest benefit for patients with advanced non-small cell lung cancer (NSCLC), with response rates of 20-35% and median survival of 10-12 months. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), gefitinib and erlotinib are active against lung cancer. In retrospective studies, EGFR-TKI therapy among patients harboring EGFR mutations showed response rates higher than 65% and a median survival of 20-30 months. Gefitinib is well tolerated and less toxic compared to conventional cytotoxic drugs, but gefitinib-related interstitial lung disease (ILD) has been reported as a serious adverse effect. Although the mechanism remains unknown, multivariate analysis revealed male sex, history of smoking, and the coexistence of interstitial pneumonia or pre-existence of pulmonary fibrosis and poor performance status were all significant risk factors. Here, we reported a case of gefitinib pneumonitis with severe hypoxemia and impending respiratory failure who showed poor response to intermediate dose of systemic steroids but good recovery with high-dose pulse therapy. less...