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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