Advancing personalized cancer medicine in lung cancer

Transforming growth factor-beta signaling network regulates plasticity and lineage commitment of lung cancer cells

Identification of target cells in lung tumorigenesis and characterization of the signals that control their behavior is an important step toward improving early cancer diagnosis and predicting tumor behavior. We identified a population of cells in the adult lung that bear the EpCAM+CD104+CD49f+CD44+CD24loSCA1+ phenotype and can be clonally expanded in culture, consistent with the properties of early progenitor cells. We show that these cells, rather than being restricted to one tumor type, can give rise to several different types of cancer, including adenocarcinoma and squamous cell carcinoma. We further demonstrate that these cells can be converted from one cancer type to the other, and this plasticity is determined by their responsiveness to transforming growth factor (TGF)-beta signaling. Our data establish a mechanistic link between TGF-beta signaling and SOX2 expression, and identify the TGF-beta/SMAD/SOX2 signaling network as a key regulator of lineage commitment and differentiation of lung cancer cells.

[Lung cancer. Molecular pathology and personalized therapy]

Recent advances in the treatment of non-small cell lung cancer (NSCLC) are based on the identification of so-called driver mutations, resulting in a more personalized treatment setting. Currently about 15% of NSCLC patients benefit from improved treatment protocols based on the genetic background of the tumor. In the last few years cancer immunotherapy has returned to the center of attention and comprises a variety of treatment approaches incorporating adaptive, as well as innate immunity. Current strategies involve the use of monoclonal antitumor antibodies, cancer vaccines, adoptive transfer of ex vivo activated T and NK cells as well as the blockade of so-called immune checkpoints (immune inhibitory pathways). Especially the combination of current treatments with immunotherapy seems promising to achieve highly potent antitumor effects. However, a profound understanding of the dynamic and complex interaction between lung cancer and the host immune system and especially its immune checkpoints is the foundation to identify potential biomarkers for a personalized cancer immunotherapy approach.