Purpose The MET receptor is involved in the pathogenesis and progression of non-small-cell lung cancer (NSCLC). Clinical trials with MET inhibitors in NSCLC are planned with patient selection based on immunohistochemistry (IHC) and/or gene copy number assessment. Therefore, a detailed understanding of relationship between these markers and prognosis is essential. Methods This study included tumors from 189 NSCLC patients who underwent pulmonary resection (median follow-up 5.3 years). MET expression was evaluated by IHC on tissue microarrays and scored according to hybrid (H) score (range: 0–400) and by scoring system used in the MetMAb trial (≥50% of cells with moderate or strong staining). MET gene copy number was assessed by silver in-situ hybridization (SISH, N=140 patients). Results Median MET IHC H-score was 60 (range: 0–400; N=174). There were no associations between clinical and pathological characteristics, disease-free or overall survival according to median value (P=0.36 and P=0.38, respectively) or other cut-points. According to MetMAb scoring criteria, IHC positivity rate was 25%, again with no associations to clinico-pathological features nor survival. In 140 tumors evaluable for MET copy number, three (2.1%) showed gene amplification and 14 (10%) had tumors with average of 5 or more copies/nucleus. There were no associations of MET copy number with clinical characteristics, disease-free or overall survival with any analyzed cut-points. Correlation between MET copy number and protein expression was significant (Pearson’s r=0.42, P<0.0001). Conclusions There is a significant correlation between MET protein expression and MET gene copy number in operable NSCLC, but neither is associated with prognosis.

PurposeThe purpose of this study was to characterize insulin-like growth factor-1 receptor (IGF1R) protein expression, mRNA expression, and gene copy number in surgically resected non–small-cell lung cancers (NSCLC) in relation to epidermal growth factor receptor (EGFR) protein expression, patient characteristics, and prognosis.Patients and MethodsOne hundred eighty-nine patients with NSCLC who underwent curative pulmonary resection were studied (median follow-up, 5.3 years). IGF1R protein expression was evaluated by immunohistochemistry (IHC) with two anti-IGF1R antibodies (n = 179). EGFR protein expression was assessed with PharmDx kit. IGF1R gene expression was evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) from 114 corresponding fresh-frozen samples. IGF1R gene copy number was assessed by fluorescent in situ hybridization using customized probes (n = 181).ResultsIGF1R IHC score was higher in squamous cell carcinomas versus other histologies (P < .001) and associated with stage (P = .03) but not survival (P = .46). IGF1R and EGFR protein expression showed significant correlation (r = 0.30; P < .001). IGF1R gene expression by qRT-PCR was higher in squamous cell versus other histologies (P = .006) and did not associate with other clinical features nor survival (P = .73). Employing criteria previously established for EGFR copy number, patients with IGF1R amplification/high polysomy (n = 48; 27%) had 3-year survival of 58%, patients with low polysomy (n = 87; 48%) had 3-year survival of 47% and patients with trisomy/disomy (n = 46; 25%) had 3-year survival of 35%, respectively (P = .024). Prognostic value of high IGF1R gene copy number was confirmed in multivariate analysis.ConclusionIGF1R protein expression is higher in squamous cell versus other histologies and correlates with EGFR expression. IGF1R protein and gene expression does not associate with survival, whereas high IGF1R gene copy number harbors positive prognostic value.

Background:To investigate whether copy number gain of MET or hepatocyte growth factor (HGF) affect trastuzumab sensitivity in HER2-positive metastatic breast cancer (MBC).Methods:We analysed 130 HER2-positive MBC treated with trastuzumab-based therapy. MET and HGF gene copy numbers (GCN) were assessed by fluorescence in situ hybridisation (FISH) in primary breast cancer samples. Receiver operating characteristic analysis was applied to find the best cutoff point for both MET and HGF GCN.Results:MET FISH-positive cases (N=36, mean ⩾3.72) had a significantly higher trastuzumab failure rate (44.4% vs 16.0% P=0.001) and a significantly shorter time to progression (5.7 vs 9.9 months; HR 1.74; P=0.006) than MET FISH-negative cases (N=94, mean <3.72). Hepatocyte growth factor GCN was evaluated in 84 cases (64.6%). Receiver operating characteristic analysis identified 33 HGF FISH-positive patients (mean HGF GCN ⩾3.01). HGF FISH-positive status was significantly associated with higher risk of failure (30.3% vs 7.8% P=0.007) as compared with HGF FISH-negative cases (N=51, mean <3.01). MET and HGF FISH-positive status was highly correlated (P<0.001) and combination of both biomarkers did not increase predictive value of either considered separately.Conclusion:High GCNs of MET and HGF associate with an increased risk of trastuzumab-based therapy failure in HER2-positive MBC.

Background. Patients with human epidermal growth factor receptor (HER)-2؉ breast cancer are at particularly high risk for brain metastases; however, the biological basis is not fully understood. Using a novel HER-2 assay, we investigated the correlation between quantitative HER-2 expression in primary breast cancers and the time to brain metastasis (TTBM) in HER-2 ؉ advanced breast cancer patients treated with trastuzumab.Methods. The study group included 142 consecutive patients who were administered trastuzumab-based therapy for HER-2 ؉ metastatic breast cancer. HER-2/

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7550 Background: IGF1R represents a novel molecular target in NSCLC. We aimed to evaluate the association between IGF1R expression, clinical characteristics and survival in operable NSCLC pts. Methods: 184 consecutive surgically treated pts (median follow up of 32 months [range: 13–51 months]) were included in the study. There were 23% females, 55% pts with squamous cell carcinoma, 28% with adenocarcinoma, 3% with large cell carcinoma, 13% with mixed carcinoma and 1% with other types, 5% were never-smokers. Median age was 64 years (range: 37–85 years). Pathological stage I was diagnosed in 41%, stage II –22%, stage III –33% and stage IV –4% pts. Induction or adjuvant treatment was not routinely used. IGF1R was evaluated in tissue microarray by immunohistochemistry and scored by two observers according to H-score, taking into account proportion of cells with positive staining times staining intensity (scale 0–400). Results: IGF1R IHC expression was low in analyzed samples (median H-score 20, range: 0–223). Higher IGF1R score was observed in adenocarcinomas vs. squamous-cell carcinomas (p=0.02) and never-smokers vs. smokers (p=0.02). IGF1R score did not depend on stage (p=0.98) and sex (p=0.83). When analyzed as a continuous variable, IGF1R score tended to associate with worse survival in the entire cohort (p=0.10), and was significantly associated with inferior survival in patients with complete (R0) resections (p=0.04). When categorized with cut-off point of 50 (30% of patients positive), IGF1R expression was again associated with poor survival (p=0.05). This association was confined to pathological stage I (hazard ratio, HR=3.07; 95% confidence interval, CI=1.41–6.70, p=0.005) vs. all other stages (HR=1.03; 95% CI=0.63–1.70, p=0.90), and to patients with adenocarcinoma histology (HR=2.67; 95%CI=1.17–6.70, p=0.02 vs. all other histologies (HR=1.28; 95%CI=0.79–2.11, p=0.32). Conclusion: In this cohort of operable NSCLC pts, high IGF1R expression was associated with never-smoking history, adenocarcinoma histology, and poor survival, particularly in stage I disease and in patients with adenocarcinoma. These results support involvement of IGF pathway in the progression of early-stage NSCLC. No significant financial relationships to disclose.

505 Background: Brain metastases (BM) of breast cancer constitute an important part of therapeutic failures and are associated with severe morbidity and mortality. The risk of BM is particularly high in HER2+ advanced breast cancer pts. We earlier developed in this group a 13-gene signature strongly predicting for rapid development of BM (J Clin Oncol 2008; 26: 45s). Now, we validated these results in an independent group of pts and on culture model system. Methods: Discovery group included 87 samples analyzed using cDNA synthesis, annealing, selection, extension, ligation and array hybridization (DASL). Independent validation group included 75 samples analyzed using quantitative reverse-transcriptase PCR. 3D culture validation model system used immortal, non-tumorigenic human MCF10A breast epithelial cells with and without ectopic expression of HER-2 and RAD51, a DNA double strand break repair gene (one of the three genes of this group overexpressed in 13-gene signature). The number and morphology of breast acini were scored using indirect immunoflourescence and confocal microscopy. Results: Median brain metastasis-free survival (BMFS) in the discovery group for ‘high’ vs. ‘low’ expression signature tumors was 36 months and 66 months, respectively (P=0.0068), and in the validation group 54 and 86 months, respectively (P=0.032). Short BMFS was also associated with ER-negativity; BMFS in the cohort of ‘high’ 13-gene signature and ER- tumors vs. other 3 groups was 31 months and 66 months in discovery group, and 41 and 77 months in validation group (P<0.0001 and P=0.02, respectively). Overexpression of RAD51 in MCF-10A breast cells altered their three-dimensional acinar morphology and increased the percentage of invasive structures by 6.5 fold, both in the presence and absence of HER2 overexpression. Conclusions: 13-gene signature and ER-negativity predict rapid development of BM in HER+ advanced breast cancer pts. RAD51 may promote aggressiveness in breast epithelial cells. These data may be useful in the design of BM preventive trials and may prompt new treatment strategies.