C. Camps

114P: Expression analysis of tumorspheres from non-small cell lung cancer show significant differences in CSC-markers and signaling pathways

monoclonal antibodies attached to pull down epithelial derived CTCs. Here, we conducted a study using this effective device, to monitor CTC counts before as well as on different time points after surgery in non-small cell lung cancer (NSCLC) patients. Methods: In total, 18 lung cancer patients (with different stages) were screened for CTCs at different time points: preoperative, 30 minutes after resection, 1 week postoperative as well as in 3-monthly intervals up to 2 years. In addition, 1 patient with a benign lung disease were included in this study. Results: Applying the GILUPI CellCollector®, CTCs were isolated independent from the tumor stages and tumor size. Moreover a difference between CTC occurrence before and after surgery was seen and we were able to detect a correlation between CTC enumeration and clinical lack of recurrence. Conclusions: The GILUPI CellCollector® overcomes blood volume limitations of other diagnostic approaches and thereby increases the diagnostic sensitivity of CTC analysis. It allows enumeration and molecular characterization of CTCs which might help to monitor therapy efficacy and improve treatment strategies. Legal entity responsible for the study: Thomas Lesser Funding: GILUPI GmbH Disclosure: All authors have declared no conflicts of interest.

149P: The role of CTCs and cfDNA for diagnosis and monitoring of EGFR mutations in advanced NSCLC patients

S. Calabuig-Fariñas1, E. Jantus Lewintre2, C. Mayo-De-Las-Casas3, A. Blasco Cordellat4, M.A. Molina-Vila3, R. Rosell5, C. Camps6. 1 Department of Pathology, Universitat de València, Molecular Oncology Laboratory, General University Hospital Research Foundation, Valencia, Spain , 2 Department of Biotechnology, Universidad Politécnica de Valencia, Molecular Oncology Laboratory, General University Hospital Research Foundation, Valencia, Spain, 3 Laboratory of Oncology/Pangaea Biotech S.L, Hospital Quiron Dexeus, Barcelona, Spain, 4 Servicio de Oncologia Medica, Hospital General Universitario Valencia, Valencia, Spain, 5 Translational Cancer Research Unit, Instituto Oncológico Dr.Rosell, Quirón Dexeus University Hospital, Catalan Institute of Oncology, Hospital Germans Trias i Pujol Badalona, Barcelona, Spain, 6 Department of Medicine, Universitat de València, Department of Medical Oncology, Hospital General Universitario Valencia, Molecular Oncology Laboratory, General University Hospital Research Foundation, Valencia, Spain

Association of Foxp3 expression with prognosis in resected non-small cell lung cancer (NSCLC).

e21114 Background: Regulatory T cells (Tregs) play a critical role in suppressing T-cell-mediated immunity in patients with cancer. A highly specific marker for Tregs is Foxp3, a transcription factor which appears to be a master control gene for their development and function. The aim of this study was to evaluate the role of Foxp3 as a prognostic marker in resectable NSCLC patients.nnnMETHODSnFoxp3 expression was assessed by RT-PCR in frozen samples (tumor and normal lung) from 150 NSCLC patients. Foxp3 relative expression was normalized by an endogenous gene (GUSB) and compared with clinicopathological variables. Statistical analyses were considered significant at p<0.05.nnnRESULTSnRT-PCR analysis showed that Foxp3 was over-expressed (>2.0X) in 41/150 tumor lung tissues. No significant associations were found between Foxp3 expression and gender, ECOG-PS, stage or histology. Patients with Foxp3 > 1.48X (median value) showed a shorter TTP (median 22.1 vs 66.6 months, p= 0.017) and OS (median 26.8 vs 49.7 months, p= 0.036) than others.nnnCONCLUSIONSnFoxp3 is a transcription factor necessary and sufficient for induction of the immunosuppressive functions in Tregs. In concordance, our results indicate that high expression of Foxp3 in tumor samples is a poor prognostic marker for TTP and OS in resectable NSCLC. It could be inferred that overcoming Treg activity, may be beneficial for the treatment of this type of cancer. Supported by grants PS09-01149 and RD06/0020/1024 from ISCIII.

Prognostic implications of lymphangiogenic markers in early-stage NSCLC.

e21108 Background: The lymphatic system constitutes one of the most important pathways for tumor cell dissemination. The process of lymphangiogenesis is mainly regulated by VEGF family members. Specifically, the activation of VEGFR-3 by the binding of VEGF-C and VEGF-D is the initial signal stimulating the proliferation and migration of lymphatic endothelial cells. The aim of the present study was to analyze the expression of these genes in a cohort of resectable NSCLC patients and to correlate them with clinico-pathological variables and prognosis.nnnMETHODSnRNA was obtained from tumor and normal lung specimens from 150 resectable NSCLC patients. RT-PCR was performed to assess the expression of VEGF-C, VEGF-D and VEGFR-3. Relative expression was normalized by an endogenous gene (GUS) using the Pfaffl formulae. Differences were considered statistically significant at p<0.05.nnnRESULTSnWe found that tumor samples had a significant lower expression of VEGF-D compared to normal tissue (0.030X). In regard to the smoking status, the group of active smoking patients showed higher expressions levels of VEGF-C and VEGFR-3 genes (p=0.012 and p=0.014, respectively). There was s trend correlating lower expression of VEGF-D with lymph node metastasis. The survival analysis revealed that the group of patients with values of VEGF-D below the median had a significantly reduced OS rate (p=0.002).nnnCONCLUSIONSnVEGF-D is a master control gene of the lymphangiogenic process and may have a crucial role in the development of metastasis, therefore the lower expression of this gene found in tumor samples compared with normal lung tissue needs to be further investigated. Moreover, the expression of VEGF-D below the median is a poor prognostic marker for OS in our cohort of early-stage NSCLC patients. Supported by grants PS09-01149 and RD06/0020/1024 from ISCIII.