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Lung cancer is one of the most frequent malignancies in the western world. Its frequent association with a wide spectrum of mutations in genes encoding various signal transducers that are often linked to therapy response, emphasizes the obvious need for improved, fast and highly efficient approaches in molecular pathology. Comprehensive analyses of the mutation status of progression and therapy relevant genes can be performed by the novel sequencing forms named next generation sequencing (NGS) providing extremely high capacities for ultra-deep sequence analyses. The 454 pyrosequencing method, the sequencing by synthesis and the semiconductor sequencing platform are now available for parallel sequencing approaches of multitudinous target genes linked to multiple tumor DNA applications. The "one molecule, one clone, one read" principle by the NGS approaches supplies not only information on allele frequencies and mutation rates but also has the advantage of a very sensitive detection of low frequency variants.

There is a growing number of soluble agonistic (IL-6, ciliary neurotropic factor, IL-11, and glia-derived neurotropic factor receptors) and antagonistic (IL-1 and TNF receptors) receptor proteins, modulating the biological functions of their cognate ligands. The physiologic role of these receptor molecules in vivo is unclear. In particular, it is not known how the specificity of function of soluble receptors after release into the blood stream is maintained. We addressed this question by studying the function of the soluble IL-6R (sIL-6R) at the cellular level in the liver. We have generated double transgenic mice coexpressing human sIL-6R and human IL-6 in the liver and have analyzed the expression patterns by in situ hybridization. The expression of the human sIL-6R, driven by the phosphoenolpyruvate carboxykinase promoter, is located mainly in periportal areas, whereas human IL-6 under the control of the metallothionein promoter is uniformly expressed throughout the liver. We show here by in situ hybridization that acute phase protein gene expression induced by human IL-6 and human sIL-6R correlated with the periportal expression of sIL-6R, indicating that sIL-6R acts mainly in an area where it is generated. We conclude that in a concentration-dependent manner, at low concentrations of sIL-6R, there is a predominantly paracrine action at the site of its generation, whereas at higher concentrations of the sIL-6R there are both local and systemic effects.