Search

Purpose: Dynamic changes in circulating tumor DNA (ctDNA) are under investigation as an early indicator of treatment outcome., Experimental Design: Serial plasma ctDNA (baseline, 8 weeks, and at progression) was prospectively incorporated into the SWOG S1403 clinical trial of afatinib ± cetuximab in tyrosine kinase inhibitor-naïve, EGFR mutation tissue-positive non-small cell lung cancer., Results: EGFR mutations were detected in baseline ctDNA in 77% (82/106) of patients, associated with the presence of brain and/or liver metastases and M1B stage. Complete clearance of EGFR mutations in ctDNA by 8 weeks was associated with a significantly decreased risk of progression, compared with those with persistent ctDNA at Cycle 3 Day 1 [HR, 0.23; 95% confidence interval (CI), 0.12-0.45; P < 0.0001], with a median progression-free survival (PFS) of 15.1 (95% CI, 10.6-17.5) months in the group with clearance of ctDNA versus 4.6 (1.7-7.5) months in the group with persistent ctDNA. Clearance was also associated with a decreased risk of death (HR, 0.44; 95% CI, 0.21-0.90), P = 0.02; median overall survival (OS): 32.6 (23.5-not estimable) versus 15.6 (4.9-28.3) months., Conclusions: Plasma clearance of mutant EGFR ctDNA at 8 weeks was highly and significantly predictive of PFS and OS, outperforming RECIST response for predicting long-term benefit., (©2022 American Association for Cancer Research.)

Purpose: FGFR1 copy-number gain (CNG) occurs in head and neck squamous cell cancers (HNSCC) and is used for patient selection in FGFR-specific inhibitor clinical trials. This study explores FGFR1 mRNA and protein levels in HNSCC cell lines, primary tumors, and patient-derived xenografts (PDX) as predictors of sensitivity to the FGFR inhibitor, NVP-BGJ398., Experimental Design: FGFR1 status, expression levels, and BGJ398 sensitive growth were measured in 12 HNSCC cell lines. Primary HNSCCs (n = 353) were assessed for FGFR1 CNG and mRNA levels, and HNSCC TCGA data were interrogated as an independent sample set. HNSCC PDXs (n = 39) were submitted to FGFR1 copy-number detection and mRNA assays to identify putative FGFR1-dependent tumors., Results: Cell line sensitivity to BGJ398 is associated with FGFR1 mRNA and protein levels, not FGFR1 CNG. Thirty-one percent of primary HNSCC tumors expressed FGFR1 mRNA, 18% exhibited FGFR1 CNG, 35% of amplified tumors were also positive for FGFR1 mRNA. This relationship was confirmed with the TCGA dataset. Using high FGFR1 mRNA for selection, 2 HNSCC PDXs were identified, one of which also exhibited FGFR1 CNG. The nonamplified tumor with high mRNA levels exhibited in vivo sensitivity to BGJ398., Conclusions: FGFR1 expression associates with BGJ398 sensitivity in HNSCC cell lines and predicts tyrosine kinase inhibitor sensitivity in PDXs. Our results support FGFR1 mRNA or protein expression, rather than FGFR1 CNG as a predictive biomarker for the response to FGFR inhibitors in a subset of patients suffering from HNSCC., (©2015 American Association for Cancer Research.)

Squamous cell lung cancer (SCC) represents an area of unmet need in lung cancer research. For the past several years, therapeutic progress in SCC has lagged behind the now more common non-small cell lung cancer histologic subtype of adenocarcinoma. However, recent efforts to define the complex biology underlying SCC have begun to bear fruit in a multitude of ways, including characterization of previously unknown genomic and signaling pathways, delineation of new, potentially actionable molecular targets, and subsequent development of a large number of agents directed against unique SCC-associated molecular abnormalities. For the first time, SCC-specific prognostic gene signatures and predictive biomarkers of new therapeutic agents are emerging. In addition, recent and ongoing clinical trials, including the Lung-MAP master protocol, have been designed to facilitate approval of targeted therapy-biomarker combinations. In this comprehensive review, we describe the current status of SCC therapeutics, recent advances in the understanding of SCC biology and prognostic gene signatures, and the development of innovative new clinical trials, all of which offer new hope for patients with advanced SCC., (©2015 American Association for Cancer Research.)

The Lung Master Protocol (Lung-MAP, S1400) is a groundbreaking clinical trial designed to advance the efficient development of targeted therapies for squamous cell carcinoma (SCC) of the lung. There are no approved targeted therapies specific to advanced lung SCC, although The Cancer Genome Atlas project and similar studies have detected a significant number of somatic gene mutations/amplifications in lung SCC, some of which are targetable by investigational agents. However, the frequency of these changes is low (5%-20%), making recruitment and study conduct challenging in the traditional clinical trial setting. Here, we describe our approach to development of a biomarker-driven phase II/II multisubstudy "Master Protocol," using a common platform (next-generation DNA sequencing) to identify actionable molecular abnormalities, followed by randomization to the relevant targeted therapy versus standard of care., (©2015 American Association for Cancer Research.)

Rapid development of molecularly targeted drugs requires a "companion diagnostic" that could delay drug development and limit availability of active drugs for relevant patients. Were the negative results from MetMab studies in patients with advanced non-small cell lung cancer due to drug failure or failure of the right companion diagnostic?, (©2014 American Association for Cancer Research.)

Purpose: FGFR1 gene copy number (GCN) is being evaluated as a biomarker for FGFR tyrosine kinase inhibitor (TKI) response in squamous cell lung cancers (SCC). The exclusive use of FGFR1 GCN for predicting FGFR TKI sensitivity assumes increased GCN is the only mechanism for biologically relevant increases in FGFR1 signaling. Herein, we tested whether FGFR1 mRNA and protein expression may serve as better biomarkers of FGFR TKI sensitivity in lung cancer., Experimental Design: Histologically diverse lung cancer cell lines were submitted to assays for ponatinib sensitivity, a potent FGFR TKI. A tissue microarray composed of resected lung tumors was submitted to FGFR1 GCN, and mRNA analyses and the results were validated with The Cancer Genome Atlas (TCGA) lung cancer data., Results: Among 58 cell lines, 14 exhibited ponatinib sensitivity (IC50 values ≤ 50 nmol/L) that correlated with FGFR1 mRNA and protein expression, but not with FGFR1 GCN or histology. Moreover, ponatinib sensitivity associated with mRNA expression of the ligands, FGF2 and FGF9. In resected tumors, 22% of adenocarcinomas and 28% of SCCs expressed high FGFR1 mRNA. Importantly, only 46% of SCCs with increased FGFR1 GCN expressed high mRNA. Lung cancer TCGA data validated these findings and unveiled overlap of FGFR1 mRNA positivity with KRAS and PIK3CA mutations., Conclusions: FGFR1 dependency is frequent across various lung cancer histologies, and FGFR1 mRNA may serve as a better biomarker of FGFR TKI response in lung cancer than FGFR1 GCN. The study provides important and timely insight into clinical testing of FGFR TKIs in lung cancer and other solid tumor types., (©2014 American Association for Cancer Research.)

pAMPK and pmTOR favorably predicted outcome in early non-small cell lung cancer (NSCLC). The differences were small. Phosphoprotein lability makes routine clinical use and validation difficult. Protein immunohistochemistry is unlikely to be clinically useful, and numerous efforts to create predictive models to select resected patients for therapy have been unsuccessful., (©2014 AACR.)

The role of cetuximab in the treatment of advanced non-small cell lung cancer (NSCLC) is currently unclear. The molecular target of cetuximab, epidermal growth factor receptor (EGFR), as measured by FISH, has shown potential as a predictive biomarker for cetuximab efficacy in NSCLC. SWOG S0819 is a phase III trial evaluating both the value of cetuximab in this setting and EGFR FISH as a predictive biomarker. This work describes the decision process for determining the design and interim monitoring plan for S0819. Six possible designs were evaluated in terms of their properties and the hypotheses that can be addressed within the design constraints. A subgroup-focused, multiple-hypothesis design was selected for S0819 that incorporates coprimary endpoints to assess cetuximab in both the overall study population and among EGFR FISH-positive (FISH(+)) patients, with the sample size determined based on evaluation in the EGFR FISH(+) group. The chosen interim monitoring plan specifies interim evaluations of both efficacy and futility in the EGFR FISH(+) group alone. The futility-monitoring plan to determine early stopping in the EGFR FISH-nonpositive group is based on evaluation within the positive group, the entire study population, and the nonpositive group. SWOG S0819 uses a design that addresses both the biomarker-driven and general-efficacy objectives of this study.

Introduction: Epidermal growth factor receptor (EGFR) protein expression in non-small cell lung cancer (NSCLC) is not recommended for predicting response to EGFR tyrosine kinase inhibitors (TKI) due to conflicting results, all using antibodies detecting EGFR external domain (ED). We tested the predictive value of EGFR protein expression for response to an EGFR TKI with an antibody that detects the intracellular domain (ID) and compared fluorescence-based Automated QUantitative Analysis (AQUA) technology to immunohistochemistry (IHC)., Methods: Specimens from 98 gefitinib-treated NSCLC Japanese patients were evaluated by IHC (n = 98 of 98) and AQUA technology (n = 70 of 98). EGFR ID (5B7)- and ED-specific antibodies (3C6 and 31G7) were compared., Results: EGFR expression evaluated with 5B7 was significantly higher in responders versus nonresponders to gefitinib both with IHC and with AQUA. ED-specific antibodies did not significantly predict response. Using AQUA and ID-specific antibody resulted in the best prediction performance with a positive and negative predictive value (PPV/NPV) for responders of 50% and 87%, respectively. EGFR expression with ID-specific antibody and AQUA also predicted responders in EGFR-mutated patients. Increased EGFR expression with the ID antibody is associated with increased median progression free survival (PFS; 11.7 months vs. 5.0, log rank, P = 0.034) and overall survival (OS; 38.6 vs. 14.9, P = 0.040) from gefitinib therapy., Conclusions: EGFR protein expression using an ID-specific antibody specifically predicts response to gefitinib in NSCLC patients, including in EGFR-mutated patients, and increased PFS/OS from gefitinib. These data suggest that the choice of diagnostic antibody and methodology matters to predict response and outcome to specific therapies. The potential clinical application needs further validation. Clin Cancer Res; 17(24); 7796-807. ©2011 AACR., (©2011 AACR.)

Purpose: VEGF receptor 2 (VEGFR-2) plays a crucial role in mediating angiogenic endothelial cell responses via the VEGF pathway, and angiogenesis inhibitors targeting VEGFR-2 are in clinical use. As angiogenesis is a host-driven process, functional heritable variation in KDR, the gene encoding VEGFR-2, may affect VEGFR-2 function and, ultimately, the extent of tumor angiogenesis., Experimental Design: We resequenced KDR using 24 DNAs each from healthy Caucasian, African American, and Asian groups. Nonsynonymous genetic variants were assessed for function by phosphorylation assays. Luciferase reporter gene assays were used to examine effects of variants on gene expression. KDR mRNA and protein expression and microvessel density (MVD) were measured in non-small cell lung cancer (NSCLC) tumor samples, and matching patient DNA samples were genotyped to test for associations with variants of interest., Results: KDR resequencing led to the discovery of 120 genetic variants, of which 25 had not been previously reported. Q472H had increased VEGFR-2 protein phosphorylation and associated with increased MVD in NSCLC tumor samples. -2854C and -2455A increased luciferase expression and associated with higher KDR mRNA levels in NSCLC samples. -271A reduced luciferase expression and associated with lower VEGFR-2 levels in NSCLC samples. -906C and 23408G associated with higher KDR mRNA levels in NSCLC samples., Conclusions: This study has defined KDR genetic variation in 3 populations and identified common variants that impact on tumoral KDR expression and vascularization. These findings may have important implications for understanding the molecular basis of genetic associations between KDR variation and clinical phenotypes related to VEGFR-2 function., (©2011 AACR.)

The development of molecular markers is crucial for improving therapy in advanced non-small cell lung cancer (NSCLC). Here, we review perspectives of biomarker-driven personalized therapy in NSCLC, with particular reference to the detection of EML4-ALK gene rearrangements. Different molecular assays, validation, and clinical application to different types of tissue specimens are discussed., (©2010 AACR.)

Background: A plethora of agents is in early stages of development for colorectal cancer (CRC), including those that target the insulin-like growth factor I receptor (IGFIR) pathway. In the current environment of numerous cancer targets, it is imperative that patient selection strategies be developed with the intent of preliminary testing in the latter stages of phase I trials. The goal of this study was to develop and characterize predictive biomarkers for an IGFIR tyrosine kinase inhibitor, OSI-906, that could be applied in CRC-specific studies of this agent., Methods: Twenty-seven CRC cell lines were exposed to OSI-906 and classified according to IC(50) value as sensitive (5 micromol/L). Cell lines were subjected to immunoblotting and immunohistochemistry for effector proteins, IGFIR copy number by fluorescence in situ hybridization, KRAS/BRAF/phosphoinositide 3-kinase mutation status, and baseline gene array analysis. The most sensitive and resistant cell lines were used for gene array and pathway analyses, along with shRNA knockdown of highly ranked genes. The resulting integrated genomic classifier was then tested against eight human CRC explants in vivo., Results: Baseline gene array data from cell lines and xenografts were used to develop a k-top scoring pair (k-TSP) classifier, which, in combination with IGFIR fluorescence in situ hybridization and KRAS mutational status, was able to predict with 100% accuracy a test set of patient-derived CRC xenografts., Conclusions: These results indicate that an integrated approach to the development of individualized therapy is feasible and should be applied early in the development of novel agents, ideally in conjunction with late-stage phase I trials., ((c) 2010 AACR.)

The majority of lung cancers are caused by long term exposure to the several classes of carcinogens present in tobacco smoke. Although a significant fraction of lung cancers in never smokers may also be attributable to tobacco, many such cancers arise in the absence of detectable tobacco exposure, and may follow a very different cellular and molecular pathway of malignant transformation. Recent studies summarized here suggest that lung cancers arising in never smokers have a distinct natural history, profile of oncogenic mutations, and response to targeted therapy. The majority of molecular analyses of lung cancer have focused on genetic profiling of pathways responsible for metabolism of primary tobacco carcinogens. Limited research has been conducted evaluating familial aggregation and genetic linkage of lung cancer, particularly among never smokers in whom such associations might be expected to be strongest. Data emerging over the past several years show that lung cancers in never smokers are much more likely to carry activating mutations of the epidermal growth factor receptor (EGFR), a key oncogenic factor and direct therapeutic target of several newer anticancer drugs. EGFR mutant lung cancers may represent a distinct class of lung cancers, enriched in the never-smoking population, and less clearly linked to direct tobacco carcinogenesis. These insights followed initial testing and demonstration of efficacy of EGFR-targeted drugs. Focused analysis of molecular carcinogenesis in lung cancers in never smokers is needed, and may provide additional biologic insight with therapeutic implications for lung cancers in both ever smokers and never smokers.

Purpose: TRIBUTE was a phase III trial evaluating the addition of erlotinib to carboplatin and paclitaxel as a first-line treatment for advanced non-small cell lung cancer that did not meet its primary end point of improving overall survival. Here, we assess the value of using epidermal growth factor receptor (EGFR) gene copy number in tumor biopsy samples, as determined by fluorescence in situ hybridization (FISH), as a predictor of treatment outcome., Methods: EGFR FISH analysis was done using LSI EGFR SpectrumOrange/CEP7 SpectrumGreen probe., Results: Of 275 samples, 245 (89.1%) were successfully analyzed by FISH. One hundred (40.8%) of patients were EGFR FISH(+). Median overall survival was not different between FISH(+) and FISH(-) patients in either the chemotherapy+erlotinib arm or the chemotherapy+placebo arm. In FISH(+) patients, median time to progression (TTP) was 6.3 months in the erlotinib arm versus 5.8 months in the placebo arm (hazard ratio, 0.59; 95% confidence interval, 0.35-0.99; P = 0.0430); in FISH(-) patients, median TTP was 4.6 months versus 6.0 months (hazard ratio, 1.42; 95% confidence interval, 0.95-2.14; P = 0.0895; treatment interaction test, P = 0.007). After 6 months of treatment, a notable separation of the TTP curves in favor of erlotinib emerged. Objective response rates were 11.6% versus 29.8% in FISH(+) patients (chemotherapy+erlotinib arm versus chemotherapy+placebo arm; P = 0.0495) and 21.8% versus 25.4%, respectively, for FISH(-) patients (P = 0.6954)., Conclusions: EGFR gene copy number by FISH did not predict survival benefit. However, among EGFR FISH(+) patients, TTP was longer in patients who received erlotinib and continued to receive it after completing first-line therapy.

Purpose: Recognition that the epidermal growth factor receptor (EGFR) was a therapeutic target in non-small cell lung cancer (NSCLC) and other cancers led to development of the small-molecule receptor tyrosine kinase inhibitors gefitinib and erlotinib. Clinical trials established that EGFR tyrosine kinase inhibitors produced objective responses in a minority of NSCLC patients. We examined the sensitivity of 23 NSCLC lines with wild-type or mutated EGFR to gefitinib to determine genes/proteins related to sensitivity, including EGFR and HER2 cell surface expression, phosphorylated EGFR expression, EGFR gene copy number, and EGFR mutational status. Downstream cell cycle and signaling events were compared with growth-inhibitory effects., Experimental Design: We determined gefitinib sensitivity by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, EGFR expression by fluorescence-activated cell sorting and immunohistochemistry, phosphorylated EGFR by Western blotting, EGFR gene copy number by fluorescence in situ hybridization, and EGFR mutation by sequencing. The cellular effects of gefitinib on cell cycle were determined by flow cytometry and the molecular effects of gefitinib EGFR inhibition on downstream signal proteins by Western blotting. Gefitinib in vivo effects were evaluated in athymic nude mice bearing sensitive and resistant NSCLC xenografts., Results: There was a significant correlation between EGFR gene copy number, EGFR gene mutations, and gefitinib sensitivity. EGFR protein was necessary but not sufficient for predicting sensitivity. Gefitinib-sensitive lines showed a G(1) cell cycle arrest and inactivation of downstream signaling proteins; resistant cell lines had no changes. The in vivo effects mirrored the in vitro effects., Conclusions: This panel of NSCLC lines characterized for gefitinib response was used to identify predictive molecular markers of response to gefitinib. Several of these have subsequently been shown to identify NSCLC patients likely to benefit from gefitinib therapy.

Recent evidence indicates that high epidermal growth factor receptor (EGFR) gene copy number evaluated by fluorescence in situ hybridization is an excellent predictive biomarker for response and survival benefit in patients with non-small cell lung cancer who receive epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. Data on EGFR protein expression by immunohistochemistry as a selection marker are conflicting, although several studies showed that the treatment benefit was confined to EGFR-positive patients. Our studies and others showed that fluorescence in situ hybridization and immunohistochemistry were associated with the best predictive value. Expeditious validation of this information in prospective clinical trials with patient selection to first-line treatment is currently being done or planned by several cancer research groups worldwide.

Purpose: Epidermal growth factor receptor (EGFR) mRNA expression and EGFR gene dosage by quantitative PCR in tumor samples obtained from patients with gefitinib-treated non-small cell lung cancer were analyzed in order to determine the association with treatment outcome, clinical, and biological features [EGFR copy number by fluorescent in situ hybridization (FISH), EGFR tyrosine kinase mutations, and EGFR protein expression]., Experimental Design: EGFR mRNA expression was measured by real-time quantitative reverse transcription-PCR in 64 patients, and EGFR gene dosage was analyzed by real-time quantitative PCR in 82 patients from paraffin-embedded specimens., Results: EGFR mRNA expression was higher in responders to gefitinib as compared with nonresponders (P = 0.012). Patients with high EGFR mRNA expression (>5.01) had 43% response probability, whereas patients with low EGFR mRNA expression had 8% response probability (P = 0.006). Patients with high EGFR mRNA expression had longer median progression-free (5.3 versus 2.8 months, P = 0.028) but not overall survival (13.8 versus 10.9 months, P = 0.87). EGFR mRNA expression was higher in FISH-positive patients (P = 0.001) and in patients with positive EGFR immunostaining (P < 0.001) but not in patients with EGFR mutations (P = 0.19). EGFR gene dosage did not predict response (P = 0.54), progression-free (P = 0.73), or overall survival (P = 0.89). EGFR gene dosage was not associated with FISH positivity (P = 0.15), relative mRNA expression (P = 0.27), EGFR mutation status (P = 0.39), and EGFR protein expression (P = 0.35)., Conclusion: EGFR mRNA expression is a predictive biomarker for response to gefitinib and to progression-free survival after gefitinib treatment. EGFR gene dosage is neither predictive for response nor progression-free nor overall survival.

Purpose: Lung cancer is preceded by a premalignant phase during which intervention could decrease associated morbidity and mortality. Molecular characterization of factors involved in controlling progression of bronchial dysplasias will provide markers of premalignant change and identify targets for chemoprevention., Experimental Design: Immunohistochemical analysis of epidermal growth factor receptor (EGFR; c-ErbB1/EGFR), HER-2/neu (c-ErbB2/HER-2), Ki-67, and minichromosome maintenance protein 2 (MCM2) expression in bronchial dysplasia was undertaken to characterize molecular alterations associated with the progression of these lesions in 268 bronchoscopically obtained biopsies from 134 subjects., Results: Analysis of biopsies with the most severe diagnosis from each subject showed a linear relationship between increasing marker expression and severity of dysplastic change for EGFR (P < 0.001), Ki-67 (P < 0.001), and MCM2 (P = 0.001) but not HER-2 (P = 0.102). Increased expression of either EGFR or HER-2 was associated with increased levels of Ki-67 and MCM2 expression, and combined overexpression of these receptors was associated with the highest levels of proliferation, suggesting a synergistic effect. Finally, the lack of an associated trend toward increased EGFR expression when comparing the worst and best biopsies within each subject indicated a potential field effect in the induction of EGFR expression., Conclusions: The results suggest a prominent role for EGFR overexpression in the development and progression of bronchial dysplasia and provide rationale for exploring inhibition of EGFR signaling in lung cancer chemoprevention.

Bronchioloalveolar carcinoma (BAC) is a previously uncommon subset of non-small cell lung cancer (NSCLC) with unique epidemiology, pathology, clinical features, radiographic presentation, and natural history compared with other NSCLC subtypes. Recent data suggest that the incidence of BAC is increasing, notably in younger nonsmoking women. Despite reports of prolonged survival after repeated surgical resection of multifocal lesions and slow growth kinetics, advanced bilateral or recurrent diffuse BAC remains incurable, with the vast majority of patients dying of respiratory failure or intercurrent pneumonia within 5 years. Limited data suggest that chemotherapy may yield poor results in BAC. However, anecdotal reports of prolonged complete response to tyrosine kinase inhibitors of the epidermal growth factor receptor (EGFR), a member of the human epidermal growth factor receptor (erbB) family, have raised considerable interest in studying this NSCLC subset. Here we present clinical data and preliminary results of correlative science studies analyzing human epidermal growth factor receptor pathways from the following two prospective Southwest Oncology Group clinical trials performed in advanced stage BAC: S9714 testing a 96-h continuous infusion of paclitaxel (Taxol) and S0126 evaluating the small molecule EGFR inhibitor gefitinib (ZD1839 or Iressa). These studies provide a biological rationale for investigating BAC as a model of predictive markers of EGFR inhibition.

The prognostic significance of epidermal growth factor receptor (EGFR) expression in lung cancer and, more importantly, its ability to predict response to anti-EGFR therapies, are currently subjects of active research. In a meta-analysis, EGFR overexpression confirmed a worse prognosis (HR 1.13) in eight studies using immunohistochemistry, although cutoff values were generally selected arbitrarily by investigators. Most applied clinical research on the EGFR has been focused on the overexpression of the receptor, whereas less research has addressed the potential role of other mechanisms of increased signaling or of nonmembrane-bound events. The emerging concept of EGFR signaling reveals a multilayered network that allows for horizontal interactions and permits multiple combinatorial responses that may explain the specificity of cellular outcomes to receptor activation. New technologies such as nucleotide arrays and proteomics will help to elucidate the issue by providing information on how EGFR signaling may affect the expression of genes and proteins in cancer cells.

Overexpression of the Her-2/neu oncogene and receptor protein was reported in approximately 20% of breast cancers and was associated with a poor prognosis. Her-2/neu expression was a predictor for response to trastuzumab, a monoclonal antibody that recognizes the Her-2/neu cell surface receptor. Data regarding the expression of Her-2/neu in lung cancer are far more limited, and there is little information regarding the influence of Her-2/neu expression and response to trastuzumab alone or in combination with chemotherapeutic agents. In this report we evaluated Her-2/neu gene expression by fluorescence in situ hybridization (FISH) and the cell surface expression of the Her-2/neu receptor by immunohistochemistry using the HercepTest and by FACS analysis in 31 lung cancer cell lines with 5 breast cancer cell lines as controls. By FACS, we found Her-2/neu overexpression (mean fluorescence intensity >8) in 2 of the 22 non-small cell lung cancer (NSCLC) cell lines (9%), none of 11 small cell lung cancer (SCLC) cell lines, and 4 of 5 breast cancer cell lines. A positive HercepTest (2+ or 3+) was found in 6 of 19 NSCLC cell lines (26%, 2+; 5%, 3+), 1 of 3 SCLC cell lines (33%), and 4 of 5 breast cancer cell lines (80%). One of 6 NSCLC cell lines examined (17%) had gene amplification with >32 copies of Her-2/neu/cell and had homogeneous staining regions. One NSCLC cell line had a maximum of 14 copies of Her-2/neu/cell, and 3 had modest increases in Her-2/neu gene copy number without gene amplification (maximum 5-8 copies/cell). None of the SCLC cell lines had more than a maximum of 4 copies/cell, whereas the 2 breast cancer cell lines had maximum Her-2/neu copy numbers of 80 and 5, respectively. Aneusomy rather than true amplification was the major cause of increased Her-2/neu expression in most of the NSCLC cell lines. There was a strong correlation when the results of fluorescence-activated cell sorter, HercepTest results, and FISH were compared in pairs. Furthermore, Trastuzumab produced a G(1) cell cycle arrest and growth inhibition only in cell lines expressing Her-2/neu. The IC(50) for growth inhibition was correlated with cell surface Her-2/neu expression. The combination of trastuzumab and chemotherapeutic agents produced more than additive growth inhibition in cell lines expressing Her-2/neu, but the level of additivity was not related to the amount of Her-2/neu expression. These data indicate that trastuzumab alone and in combination with chemotherapeutic agents should be tested in NSCLC patients and that Her-2/neu should be assessed by both immunohistochemistry and FISH methods in these studies to determine which test is the best predictor of outcome.

Lung cancer is the most common cause of cancer death in developed countries. The prognosis is poor, with less than 15% of patients surviving 5 years after diagnosis. The poor prognosis is attributable to lack of efficient diagnostic methods for early detection and lack of successful treatment for metastatic disease. Most patients (>75%) present with stage III or IV disease and are rarely curable with current therapies. Within the last decade, rapid advances in molecular biology, pathology, bronchology, and radiology have provided a rational basis for improving outcome. These advancements have led to a better documentation of morphological changes in the bronchial epithelium before development of clinical evident invasive carcinomas. This has changed our concept of lung carcinogenesis and emphasized the multistep carcinogenesis approach on several levels. Combined with the technical developments in bronchoscopic techniques, e.g., laser-induced fluorescence endoscope (LIFE) bronchoscopy, we now have improved methods to localize preinvasive and early-invasive bronchial lesions. With the LIFE bronchoscope, a new morphological entity (angiogenic squamous dysplasia) has been recognized, which might be an important biomarker and target for antiangiogenic chemopreventive agents. To reduce the mortality of lung cancer, these new technologies have been taken into the clinic in different scientific settings. The use of low-dose spiral computed tomography in the screening of a high-risk population has demonstrated the possibility of diagnosing small peripheral tumors that are not seen on conventional X-ray. A shift in the therapeutic paradigm from targeting advanced clinically manifest lung cancer toward asymptomatic preinvasive and early-invasive cancer is occurring. The present article reviews the recent advances in the diagnosis of preinvasive and early-invasive cancer to identify biomarkers for early detection of lung cancer and for chemoprevention studies.