mTOR Signaling Pathway

Through two distinct protein complexes mTORC1 and mTORC2, the mechanistic Target of Rapamycin (mTOR) coordinates eukaryotic cell growth and metabolism with environmental inputs including nutrients and growth factors ⁽¹⁾. mTOR was also shown to be regulated by other external stresses, such as oxygen deprivation (hypoxia), radiation, high salt concentration, DNA topoisomerase inhibitors, and histone deacetylase inhibitors ⁽⁶⁾.
The distinct roles of mTOR were identified in gene transcription, protein synthesis, tissue regeneration and repair, oxidative stress, immunity, aging, and cell death that include autophagy and apoptosis, insulin resistance, adipogenesis, and T-lymphocyte activation ^(2,4).

The de-regulated activity of mTOR is involved in many pathophysiological conditions, such as aging, Alzheimer’s disease, obesity, diabetic complications, pulmonary hypertension, cardiovascular diseases, neurodegeneration, and cancer ^(2,3,7).
Through diverse mechanisms (promotion of growth factor receptor signaling, angiogenesis, glyolytic metabolism, lipid metabolism, cancer cell migration, and suppression of autophagy), recent studies suggest that mTOR signaling pathway plays an essential role in the regulation of tumor cell motility, invasion and metastasis ⁽⁵⁾. Hence, mTOR is a promising target for cancer therapy by developing mTOR inhibitors ⁽⁷⁾.