Institute Cytology and Genetics

The Oncogenetics Laboratory

Head V.A.Lavrovsky, Dr.Biol.Sci.

Reversion of different tumor cells to normal phenotype

Latent periods of tumor appearance after inoculation of different revertant clones from FCBA2V40 and FC3H3V7 sarcomas

Reversion frequencies of FCBA2V40 sarcoma cells in the process of recloning

Many patients presenting primary tumors already have dormant micrometastatic deposits. Metastatic deposits can be dormant for many years in certain patients. In recent years, the group has focused attention on studies of the mechanisms of the process. The researchers of the Section related the phenomenon with the transient reversion of tumor cells to the normal phenotype. They have shown that many murine and human tumors are able to revert to a normal phenotype in vitro. Furthermore, reversion frequency is an inherited trait of each cell line. It is important that such revertants can readily revert back to the transformed phenotype in vitro and in vivo at different times. The team is attempting to identify the reversion mechanism by using the unique collection of reverted clones.

1. The cDNA library derived from the tumor and reverted clones using the differential display method is under study.

2. The role of different compounds of AP-1 transfection factors in the reversion process is examined.

3. The role of the newly identified growth protein (UGF) secreted by the tumor clones is under study.