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OBJECTIVES: Serum response factor (SRF), E2F1 and survivin are well-known factors involved in a multitude of cancer-related regulation processes. However, to date, no suitable means has been found to apply their potential in the therapy of non-small cell lung cancer (NSCLC). This study deals with questions of small interfering ribonucleic acid (siRNA) transfection efficiency by a non-viral transfection of NSCLC cell-lines and the power of siRNA to transiently influence cell division by specific silencing. METHODS: Different NSCLC cell lines were cultured under standard conditions and transfected, with specific siRNA targeting SRF, E2F1 and survivin in a non-viral manner. Cells treated with non-specific siRNA (SCR-siRNA) served as controls. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for messenger RNA (mRNA) expression levels. Additionally, transfection efficiency was evaluated by flow cytometry. The analysis of cell proliferation was determined with a CASY cell counter 3 days after transfection with SRF or SCR-siRNA. RESULTS: Transfection of the NSCLC cell lines with specific siRNAs against SRF, E2F1 and survivin resulted in a very considerable reduction of the intracellular mRNA concentration. CASY confirmation of cell viability demonstrated an excellent survival of the cell lines treated with non-specific siRNA, in contrast to with application of specific siRNA. CONCLUSIONS: This study reports a reliable transfectability of NSCLC-cell lines by siRNA, initially in a non-viral manner, and a reproducible knockdown of the focussed targets, consequently leading to the death of the tumour cells. This constitutes a strong candidate for a new assessment strategy in the therapy of non-small cell lung cancer.

OBJECTIVES: Lung cancer is the leading cause of death in cancer statistics throughout developed countries. While single surgical approach provides best results in early stages, multimodality approaches have been employed in advanced disease and demonstrated superior results in selected patients. With either full-dose chemotherapy and/or radiotherapy, patients usually have a poor general condition when entering surgical therapy and therefore neoadjuvant therapy can lead to a higher morbidity and mortality. Especially in the case of pneumonectomy as the completing procedure, mortality rate can exceed over 40%. Therefore, chest physicians often shy away from recommending pneumonectomy as final step in trimodal protocols. We analysed our experience with pneumonectomy after neoadjuvant chemoradiotherapy in advanced non-small-cell lung cancer (NSCLC) with a focus on feasibility, outcome and survival. METHODS: Retrospective, single-centre study of 146 patients with trimodal neoadjuvant therapy for NSCLC Stage III over 17 years time span. Follow-up was taken from our own outpatient files and with survival check of central registry office in Baden-Wurttemberg, Germany. RESULTS: A total of 118 men and 28 women received 62 lobectomies, 6 bi-lobectomies and 78 pneumonectomies after two different neoadjuvant protocols for Stage III NSCLC. Overall morbidity rate was 53 and 56% after pneumonectomy. Overall hospital mortality rate was 4.8 and 6.4% after pneumonectomy. Overall median survival rate was 31 months with a 5-year survival rate of 38% (Kaplan– Meier). Pneumonectomy, right-sited pneumonectomy and initial T- and N-stages were no risk factors for survival (log-rank test). Significant factors for survival were ypT-stage, ypN-stage, yUICC-stage in univariate testing (log-rank test) and ypUICC-stage in multivariate testing (Cox’s regression). CONCLUSIONS: Pneumonectomy in neoadjuvant trimodal approach for Stage III NSCLC can be done safe with acceptable mortality rate. Patients should not withhold from operation because of necessitating pneumonectomy. Not the procedure but the selection, response rate and R0-resection are crucial for survival after trimodal therapy in experienced centres.