What does "rapamycin-sensitive oncogenic transformation" mean?
The mammalian target of rapamycin (mTOR) is a Ser/Thr protein kinase that functions as an ATP and amino acid sensor to balance nutrient availability and cell growth. When sufficient nutrients are available, mTOR responds to a phosphatidic acid-mediated signal to transmit a positive signal to p70 S6 kinase and participate in the inactivation of the eIF4E inhibitor, 4E-BP1. These events result in the translation of specific mRNA subpopulations. mTOR is phosphorylated via the PI3 kinase/Akt signaling pathway and also autophosphorylates under translationally repressive conditions. mTOR plays a key role in cell growth and homeostasis and may be abnormally regulated in tumors. It is currently under investigation as a potential target for anti-cancer therapy.

The mTOR signaling pathway shows how mTOR is involved in numerous cell processes that can be dysregulated in cancer, including cell growth, proliferation, angiogenesis, autophagy, and various kinds of metabolism. "Rapamycin-sensitive oncogenic transformation" therefore means that the transformed cells still have intact "wild-type" mTOR complexes that can be down-regulated by the tumor-specific administration of rapamycin analogues, hence inhibiting the above-mentioned processes and arresting or killing the cells.