USE OF A LIGHT-INDUCIBLE ONCOGENE TO STUDY CELL COMPETITION
Isabelle Bonnet1,2, Sarah Moitrier1,2, Olivier Destaing3,4, Pascal Silberzan1,2,
1Institut Curie, France;
2CNRS; UPMC; Sorbonne Universités; PSL;
3Institut Albert Bonniot;
4Inserm; CNRS; Université Grenoble Alpes
To preserve its function, epithelia must eliminate cells that undergo mutations. For example, when tumor cells are present in a healthy tissue, they will compete with the non-transformed cells. This competition results in the development of the tumor or its regression if the healthy tissue can overcome this threat via the extrusion of the transformed cells.
It is well accepted that interactions between transformed cells and their environment (including the normal neighboring cells) play an important role in the early stages of the development of a tumor. However, the interplay of mechanical environment remains unclear as well as the understanding of the interactions between normal cells and a group of transformed cells. We aim at studying the dynamics at the interface between normal and transformed cells in relation with its environment: mechanical state and oncogene activity. The key in these problems is to achieve a good control of the local environment and the initial conditions in space and time. Our strategy consists in a precise tuning of the oncogene transformation using a light-inducible oncogene combined to light patterning in order to create a precisely controlled interface between the two cell types.
We designed a stable MDCK “opto-Src” cell line: if these cells are not exposed to light, they behave like normal MDCK cells, but they overexpress Src oncogene when exposed to blue light. It is therefore possible to select a subset of cells to transform within a normal tissue, using targeted light. We observe that the activation of a circular patch of cells within a tissue gives rise to a budding 3D structure, and are currently characterizing this structure.