Concomitant high gene copy number and protein overexpression of IGF1R and EGFR negatively affect disease-free survival of surgically resected non-small-cell-lung cancer patients

BACKGROUND

Insulin-like growth factor 1 receptor (IGF1R) represents a novel molecular target in non-small-cell-lung cancer (NSCLC). IGF1R and epidermal growth factor receptor (EGFR) activation are essential to mediate tumor cell survival, proliferation, and invasion. This study investigates the prognostic role of IGF1R and EGFR in surgically resected NSCLC.

MATERIALS AND METHODS

IGF1R and EGFR copy number gain (CNG) were tested by fluorescence in situ hybridization (FISH) and protein expression by immunohistochemistry (IHC) in 125 stage I-II-IIIA NSCLC patients.

RESULTS

Fourty-six tumors (40.3%) were IGF1R FISH-positive (FISH+), and 76 (67.2%) were EGFR FISH+. Tumors with concomitant IGF1R/EGFR FISH+ were observed in 34 cases (30.1%). IGF1R and EGFR FISH+ were associated with SCC histology (p = 0.01 and p = 0.04, respectively). IGF1R and EGFR protein over-expression (IHC+) were detected in 45 (36.0%) and 69 (55.2%) cases, respectively. Tumors with concomitant IGF1R/EGFR IHC+ were detected in 31 (24.8%) patients. IGF1R/EGFR FISH+ and IGF1R/EGFR IHC+ were significantly associated (χ(2) = 4.02, p = 0.04). Patients with IGF1R/EGFR FISH+ and IGF1R/EGFR IHC+ were associated with shorter disease-free survival (DFS) (p = 0.05 and p = 0.05, respectively). Patients with concomitant IGF1R/EGFR FISH+/IHC+ had a worse DFS and overall survival (p = 0.005 and p = 0.01, respectively). The multivariate model confirmed that IGF1R/EGFR FISH+/IHC+ (hazard ratio (HR), 4.08; p = 0.01) and tumor stage (II-III vs I) (HR, 4.77; p = 0.003) were significantly associated with worse DFS.

CONCLUSIONS

IGF1R/EGFR FISH+ correlates with IGF1R/EGFR IHC+. IGF1R/EGFR FISH+/IHC+ is an independent negative prognostic factor for DFS in early NSCLC. These features may have important implications for future anti-IGF1R therapeutic approaches.

[Dust and silica exposure on metallurgical furnace maintenance using refractory materials]

In the metallurgical industries the silica risk has long been known, particularly for the refractoryes maintenance workers. The maintenance of furnaces, ladles and tundisches refractory linings, on the current organization of production, is provided by companies under contract. The information available about the characterization of risk for this group of workers are at present inadequate. The study investigates the exposure to dust, also containing free crystalline silica (SLC), through the analysis of samples of commercial products used in the reconstruction of refractory linings of furnaces, ladles and tundisches, materials from the demolition of refractory articles and dust from work areas. It also presents the results of an environmental investigation conducted during the demolition and reconstruction of the refractory in three steel mills. The Authors, by the numerous inspections and the systematic survey of working conditions, have formulated a SLC risk profile and some proposals for prevention.

Correlation of polymorphisms of genes involved in platinum/gemcitabine (P/G)-based metabolism with toxicity and clinical response in patients (pts) with advanced non-small cell lung cancer (NSCLC)

8093

Background: Selecting patients according to key genetic characteristics may help to tailor chemotherapy and optimize the treatment in NSCLC. Genetic variations in drugs metabolism may affect the clinical response, toxicity and prognosis of NSCLC pts treated with P/G-based therapy. Methods: We evaluated 8 single nucleotide polymorphisms (SNPs) of 6 genes (P53 Arg72Pro (G/C); XRCC3 Thr241Met (C/T); XPD Lys751Gln (A/C); ERCC1 Asn118Asn (C/T); CDA Lys27Gln (A/C), Ala70Thr (G/A), Thr145Thr (C/T) and RRM1 C524T) involved in P/G-based metabolism in a homogeneous population of pts with advanced NSCLC treated with this regime. Genomic DNA was extracted from whole blood samples using the QIAamp DNA estraction kit on Biorobot EZ1 (Qiagen). Polymorphisms were detected with TaqMan-probe based assays using the 7300 Real-Time PCR System (Applied Biosystems, Foster City, CA). Association between SNPs and response, toxicity, progression free survival and overall survival was estimated using logistic regression model, the Kaplan-Meier method, the long-rank test and the Cox proportional hazard model. Results: We performed a retrospective analysis in 192 chemotherapy-naive pts (median age 63 years), including M/F:74/26%; stage IIIb/IV:24/76%; Adeno/Squa/other Ca:42/27/31%; ECOG PS:0–1/2–3:94/6%. Overall response rate was 32.3%, stable disease 25% and disease progression 42.7%. The CDA Thr145Thr T/T genotype significantly correlated with poorer response (partial response in 23.1% of pts versus 42.3% and 34.6% in C/T and C/C genotypes, respectively; p=0.03). The ERCC1 T/T genotype was significantly associated with haematological toxicity (G1–4) (p=0.05) compared to ERCC1 C/C allele. The CDA Thr145Thr C/T genotype was significantly associated with non-haematological toxicity (G3–4) (p=0.02) compared to CDA Thr145Thr C/C allele. The median overall survival (OS) time and progression free survival (PFS) were 12.7 and 4.7 months, respectively. None of the analyzed polymorphisms was related to PFS or OS. Conclusions: These data suggest that genetic polymorphisms in the ERCC1 and CDA genes may modulate the toxicity and response to P/G-based therapy in pts with advanced NSCLC.

No significant financial relationships to disclose.

Effect of genetic polymorphisms on toxicity and survival in advanced non-small cell lung cancer (NSCLC) patients (pts) treated with carboplatin (CBDCA) and pemetrexed disodium regimen

e19028

Background: Identification of genetic polymorphisms which influence chemotherapy outcome may help towards individually optimized therapy. We investigated the influence of ten single nucleotide polymorphisms (SNPs) of 7 genes (P53 Arg72Pro (G/C); XRCC3 Thr241Met (C/T); XPD Lys751Gln (A/C); ERCC1 Asn118Asn (C/T); GARFT C/G, GARFT C/T, DHFR C/G, DHFR A/G, TS 5’UTR, TS 3’UTR involved with metabolism of CBDCA and Alimta regimen in pts with advanced NSCLC. Methods: Genomic DNA was extracted from whole blood samples using the QIAamp DNA estraction kit on Biorobot EZ1 (Qiagen). Polymorphisms were detected with TaqMan-probe based assays using the 7300 Real-Time PCR system (Applied Biosystems, Foster City, CA) or PCR followed by RFLP. The results of SNPs were assessed by Cox model for survival/PFS & logistics regression for response/toxicity. Results: We performed a retrospective analysis in 57 advanced pretreated (2nd or 3th line) NSCLC pts treated with CBDCA(AUC=5) + Alimta (500 mg/m2). Median age was 59 years (range 26–79), M/F:63/37%; Adeno/Squa/other Ca:65/20/15%; ECOG PS:0–1/2–3:96/4%. Overall response rate was 38.6%, stable disease 38.6% and disease progression 21.1%. At median follow-up of 7.9 months, 10 pts (17.5%) died, 47 pts (82.5%) are alive. The median progression free survival (PFS) was 7.4 months, the median survival time not reached. P53 Pro72Pro was significantly associated with shorter survival (HR 5.5, 95%CI 1.01–30.5, p=0.04) when compared to P53 Arg72Arg. None of the analyzed polymorphisms was related to response to therapy. No associations were found between the analyzed polymorphisms and toxicity considered either as the maximum observed grade, or as sum of each toxicity pattern grade, probably due to low number of events observed for toxicity within this data set. Conclusions: P53 Pro72Pro may be associated with shorter survival in pts with advanced NSCLC. Further studies are warranted to validate this finding. Genotype-related differences in common toxicities and in response to therapy were not observed. The small sample size limits interpretation of these data.

No significant financial relationships to disclose.