Total and mutated EGFR quantification in cell-free DNA from non-small cell lung cancer patients detects tumor heterogeneity and presents prognostic value.

Mutation analysis of epidermal growth factor receptor (EGFR) gene is essential for treatment selection in non-small cell lung cancer (NSCLC). Analysis is usually performed in tumor samples. We evaluated the clinical utility of EGFR analysis in plasma cell-free DNA (cfDNA) from patients under treatment with EGFR inhibitors. We selected 36 patients with NSCLC and EGFR-activating mutations. Blood samples were collected at baseline and during treatment with EGFR inhibitors. Wild-type EGFR, L858R, delE746-A750, and T790M mutations were quantified in cfDNA by droplet digital PCR. Stage IV patients had higher total circulating EGFR copy levels than stage I (3523 vs. 1003 copies/mL; p < 0.01). There was high agreement for activating mutations between baseline cfDNA and tumor samples, especially for L858R mutation (kappa index = 0.679; p = 0.001). In 34 % of advanced NSCLC patients, we detected mutations in cfDNA not previously detected in tumor samples and double mutations in 17 %. Patients with baseline total EGFR copy levels above the median presented decreased overall survival (OS) (341 vs. 870 days, p < 0.05) and progression-free survival (PFS) (238 vs. 783 days; p < 0.05) compared with those with total EGFR copy levels below the median. Patients with baseline concentrations of activating mutations above the median (94 copies/mL) had lower OS (317 vs. 805 days; p < 0.05) and PFS (195 vs. 724 days; p < 0.05). During follow-up, T790M resistance mutation was detected in 53 % of patients. Total and mutated EGFR analysis in cfDNA seems a relevant tool to characterize the molecular profile and prognosis of NSCLC patients harboring EGFR mutations.

Complement activation product C4d in oral and oropharyngeal squamous cell carcinoma.

OBJECTIVE: Complement C4d-containing fragments have been proposed as diagnostic markers for lung cancer. The purpose of this study was to evaluate the presence of C4d in oropharyngeal (OPSCC) and oral (OSCC) squamous cell carcinomas. SUBJECTS AND METHODS: C4d staining was analyzed by immunohistochemistry in 244 OPSCC surgical specimens. C4d levels were quantified by ELISA in resting saliva samples from 48 patients with oral leukoplakia and 62 with OSCC. Plasma samples from 21 patients with leukoplakia and 30 with oral carcinoma were also studied. RESULTS: C4d staining in OPSCC specimens was associated with nodal invasion (P = 0.001), histopathologic grade (P = 0.014), disease stage (P = 0.040), and focal-adhesion kinase expression (P < 0.001). No association was found between C4d and prognosis. Saliva C4d levels were higher in patients with oral cancer than in subjects with leukoplakia (0.07 ± 0.07 vs 0.04 ± 0.03 µg ml(-1) , P = 0.003). The area under the ROC curve was 0.63 (95%CI: 0.55-0.71). Salivary C4d levels in stage IV patients were higher than in patients with earlier stages (P = 0.028) and correlated with tumor size (P = 0.045). Plasma C4d levels also correlated with salivary C4d levels (P = 0.041), but differences between patients with oral cancer and subjects with leukoplakia were not significant (1.26 ± 0.59 vs 1.09 ± 0.39 µg ml(-1) , P = 0.232). CONCLUSION: C4d-containing fragments are detected in oral primary tumors and are increased in saliva from patients with OSCC.

TGFBI expression is an independent predictor of survival in adjuvant-treated lung squamous cell carcinoma patients.

BACKGROUND: Transforming growth factor ß-induced protein (TGFBI) is a secreted protein that mediates cell anchoring to the extracellular matrix. This protein is downregulated in lung cancer, and when overexpressed, contributes to apoptotic cell death. Using a small series of stage IV non-small cell lung cancer (NSCLC) patients, we previously suggested the usefulness of TGFBI as a prognostic and predictive factor in chemotherapy-treated late-stage NSCLC. In order to validate and extend these results, we broaden the analysis and studied TGFBI expression in a large series of samples obtained from stage I-IV NSCLC patients. METHODS: TGFBI expression was assessed by immunohistochemistry in 364 completely resected primary NSCLC samples: 242 adenocarcinomas (ADCs) and 122 squamous cell carcinomas (SCCs). Kaplan-Meier curves, log-rank tests and the Cox proportional hazards model were used to analyse the association between TGFBI expression and survival. RESULTS: High TGFBI levels were associated with longer overall survival (OS, P<0.001) and progression-free survival (PFS, P<0.001) in SCC patients who received adjuvant platinium-based chemotherapy. Moreover, multivariate analysis demonstrated that high TGFBI expression is an independent predictor of better survival in patients (OS: P=0.030 and PFS: P=0.026). CONCLUSIONS: TGFBI may be useful for the identification of a subset of NSCLC who may benefit from adjuvant therapy.

Overexpression of TMPRSS4 in non-small cell lung cancer is associated with poor prognosis in patients with squamous histology.

BACKGROUND: Mortality rates in lung cancer patients have not decreased significantly in recent years, even with the implementation of new therapeutic regimens. One of the main problems is that a large proportion of patients present local or distant metastasis at the time of diagnosis. The need for identification of novel biomarkers and therapeutic targets for a more effective management of lung cancer led us to investigate TMPRSS4, a protease reported to promote tumour growth and metastasis. MATERIAL AND METHODS: In all, 34 lung cancer cell lines were used to evaluate the TMPRSS4 expression. Cell migration and clonogenic assays, and an in-vivo lung metastasis model were used for functional analysis of the TMPRSS4 downregulation in H358, H441 and H2170 cell lines. The TMPRSS4 expression analysis in normal and malignant lung tissue samples was performed by qPCR. Five different microarray-based publicly available expression databases were used to validate our results and to study prognosis. RESULTS: The TMPRSS4 knock down in H358, H441 and H2170 cells resulted in a significant reduction in proliferation, clonogenic capacity and invasion. A significant (P<0.05) decrease in the lung colonisation and growth was found when mice were injected with TMPRSS4-depleated H358-derived clones, as compared with controls. Expression of TMPRSS4 showed a >30-fold increase (P<0.001) in tumours in comparison with non-malignant samples. Levels in tumours with squamous cell carcinoma (SCC) histology were found to be significantly higher (P<0.001) than those with adenocarcinoma (AC) histology, which was confirmed in data retrieved from the microarrays. Kaplan-Meier curves demonstrated that high levels of TMPRSS4 were significantly associated (P=0.017) with reduced overall survival in the patients with SCC histology, whereas no correlation was found for the AC histology. CONCLUSION: Our results demonstrate that TMPRSS4 has a role in the lung cancer development. The potential use of TMPRSS4 as a biomarker for lung cancer detection or as a predictor of patient's outcome warrants further investigation.

EUELC project: a multi-centre, multipurpose study to investigate early stage NSCLC, and to establish a biobank for ongoing collaboration.

The European Early Lung Cancer (EUELC) project aims to determine if specific genetic alterations occurring in lung carcinogenesis are detectable in the respiratory epithelium. In order to pursue this objective, nonsmall cell lung cancer (NSCLC) patients with a very high risk of developing progressive lung cancer were recruited from 12 centres in eight European countries: France, Germany, southern Ireland, Italy, the Netherlands, Poland, Spain and the UK. In addition, NSCLC patients were followed up every 6 months for 36 months. A European Bronchial Tissue Bank was set up at the University of Liverpool (Liverpool, UK) to optimise the use of biological specimens. The molecular-pathological investigations were subdivided into specific work packages that were delivered by EUELC Partners. The work packages encompassed mutational analysis, genetic instability, methylation profiling, expression profiling utilising immunohistochemistry and chip-based technologies, as well as in-depth analysis of FHIT and RARbeta genes, the telomerase catalytic subunit hTERT and genotyping of susceptibility genes in specific pathways. The EUELC project engendered a tremendous collaborative effort, and it enabled the EUELC Partners to establish protocols for assessing molecular biomarkers in early lung cancer with the view to using such biomarkers for early diagnosis and as intermediate end-points in future chemopreventive programmes.

Molecular characterization of small peripheral lung tumors based on the analysis of fine needle aspirates.

The computed tomography (CT)-based early lung cancer diagnostic technologies allow the detection of very small stage I lung tumors. As part of these screening protocols any suspicious nodule has to be diagnosed morphologically, which requires CT-guided Fine Needle Aspiration, open biopsy or surgery. Fine Needle Aspiration (FNA) cytology is a well-recognised method for a rapid and accurate diagnosis of small lung tumors. Molecular analysis of the FNA specimens could complement cytology diagnosis by the characterization of the biological traits at the preoperative stage. In this study, we aimed to characterize the biological profile of 33 paraffin-embedded transthoracic FNA samples obtained from three groups of lung cancer patients: two groups of small early-detected lung adenocarcinomas (radiologically subsolid and solid nodules) and a third group of small metastatic adenocarcinomas. Genetic analysis was performed by fluorescence in situ hybridization using the four-color LAVysion probe. p53 and Ki-67 protein expression was also evaluated by immunocytochemistry. The samples showed gains for all targets analyzed; two cases had EGFR gene amplification and two cases had MYC amplification. There were no significant differences in the percentage of genetically malignant cells and the expression of Ki-67 among the three groups. However, p53 accumulation was significantly higher in the metastatic group compared to the subsolid early-detected group (P = 0.001). In conclusion, molecular analysis of FNA specimens may provide useful information at preoperative stages. In our series, a good prognostic profile in subsolid early detected adenocarcinomas is suggested.

A blood-tumor barrier limits gene transfer to experimental liver cancer: the effect of vasoactive compounds.

We have evaluated gene transfer efficiency to tumor nodules in diethylnitrosoamine (DENA)-induced hepatocellular carcinoma (HCC) in rats using adenoviral vectors administered by three different routes: intraportal, intra-arterial and intratumoral injection. Our results showed that intraportal infusion could not transduce tumor nodules greater than 1 mm in diameter while the intra-arterial route allowed transduction of nodules up to 2-5 mm in diameter. Tumors greater than this size were resistant to transduction by intravascular route, but could be transduced by direct intratumoral injection, indicating that the obstacle preventing gene transfer to tumor cells was mainly at the level of tumor vasculature and not at the level of neoplastic cells. We have studied the extracellular matrix in tumoral lesions to assess whether nodules with different size and histological pattern have different profiles in relation to transduction efficacy. Immunohistochemical detection showed a high expression of fibronectin (FN), laminin (LN) and alpha-smooth muscle actin (alpha-SMA) in those large HCC, which were resistant to adenoviral infection. Intra-arterial infusion of vasoactive compounds (histamine, angiotensin II or nitric oxide donor nitroglycerin) before vector administration enhanced gene transfer to tumor nodules that were poorly transduced without pre-treatment. Nitroglycerin was active to enhance transduction of large tumors with trabecular or pseudoglandular histological pattern, which were impermeable to adenoviral vectors even after histamine or angiotensin treatments. Our data indicate the presence of a physical barrier between blood and neoplastic cells, which prevents transduction of the tumor by vectors given by the intravascular route. The thickness and impermeability of the barrier increases as the tumor nodule grows. Vasoactive compounds may be of value in gene therapy of liver cancer by increasing transduction efficiency by intravascularly administered vectors.