PMID- 38474373 OWN - NLM STAT- MEDLINE DCOM- 20240314 LR - 20240315 IS - 2073-4409 (Electronic) IS - 2073-4409 (Linking) VI - 13 IP - 5 DP - 2024 Feb 27 TI - Discrete Mechanistic Target of Rapamycin Signaling Pathways, Stem Cells, and Therapeutic Targets. LID - 10.3390/cells13050409 [doi] LID - 409 AB - The mechanistic target of rapamycin (mTOR) is a serine/threonine kinase that functions via its discrete binding partners to form two multiprotein complexes, mTOR complex 1 and 2 (mTORC1 and mTORC2). Rapamycin-sensitive mTORC1, which regulates protein synthesis and cell growth, is tightly controlled by PI3K/Akt and is nutrient-/growth factor-sensitive. In the brain, mTORC1 is also sensitive to neurotransmitter signaling. mTORC2, which is modulated by growth factor signaling, is associated with ribosomes and is insensitive to rapamycin. mTOR regulates stem cell and cancer stem cell characteristics. Aberrant Akt/mTOR activation is involved in multistep tumorigenesis in a variety of cancers, thereby suggesting that the inhibition of mTOR may have therapeutic potential. Rapamycin and its analogues, known as rapalogues, suppress mTOR activity through an allosteric mechanism that only suppresses mTORC1, albeit incompletely. ATP-catalytic binding site inhibitors are designed to inhibit both complexes. This review describes the regulation of mTOR and the targeting of its complexes in the treatment of cancers, such as glioblastoma, and their stem cells. FAU - Jhanwar-Uniyal, Meena AU - Jhanwar-Uniyal M AD - Department of Neurosurgery, Westchester Medical Center, New York Medical College, Valhalla, NY 10595, USA. FAU - Zeller, Sabrina L AU - Zeller SL AD - Department of Neurosurgery, Westchester Medical Center, New York Medical College, Valhalla, NY 10595, USA. FAU - Spirollari, Eris AU - Spirollari E AD - Department of Neurosurgery, Westchester Medical Center, New York Medical College, Valhalla, NY 10595, USA. FAU - Das, Mohan AU - Das M AD - Department of Neurosurgery, Westchester Medical Center, New York Medical College, Valhalla, NY 10595, USA. FAU - Hanft, Simon J AU - Hanft SJ AD - Department of Neurosurgery, Westchester Medical Center, New York Medical College, Valhalla, NY 10595, USA. FAU - Gandhi, Chirag D AU - Gandhi CD AD - Department of Neurosurgery, Westchester Medical Center, New York Medical College, Valhalla, NY 10595, USA. LA - eng GR - NA/Advanced Research Foundation/ PT - Journal Article PT - Review DEP - 20240227 PL - Switzerland TA - Cells JT - Cells JID - 101600052 RN - 0 (Intercellular Signaling Peptides and Proteins) RN - EC 2.7.11.1 (Mechanistic Target of Rapamycin Complex 1) RN - EC 2.7.11.1 (Mechanistic Target of Rapamycin Complex 2) RN - EC 2.7.1.- (Phosphatidylinositol 3-Kinases) RN - EC 2.7.11.1 (Proto-Oncogene Proteins c-akt) RN - W36ZG6FT64 (Sirolimus) RN - EC 2.7.11.1 (TOR Serine-Threonine Kinases) SB - IM MH - Humans MH - *Glioblastoma/metabolism MH - Intercellular Signaling Peptides and Proteins/therapeutic use MH - Mechanistic Target of Rapamycin Complex 1/metabolism MH - Mechanistic Target of Rapamycin Complex 2/metabolism MH - Phosphatidylinositol 3-Kinases/metabolism MH - Proto-Oncogene Proteins c-akt/metabolism MH - Signal Transduction MH - *Sirolimus/pharmacology MH - TOR Serine-Threonine Kinases/metabolism MH - *Neoplastic Stem Cells/metabolism PMC - PMC10930964 OTO - NOTNLM OT - 4E-BP1 OT - GBM OT - S6K OT - mTOR OT - mTORC1 OT - mTORC2 COIS- The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results. EDAT- 2024/03/13 06:47 MHDA- 2024/03/14 06:47 PMCR- 2024/02/27 CRDT- 2024/03/13 01:25 PHST- 2024/01/16 00:00 [received] PHST- 2024/02/14 00:00 [revised] PHST- 2024/02/22 00:00 [accepted] PHST- 2024/03/14 06:47 [medline] PHST- 2024/03/13 06:47 [pubmed] PHST- 2024/03/13 01:25 [entrez] PHST- 2024/02/27 00:00 [pmc-release] AID - cells13050409 [pii] AID - cells-13-00409 [pii] AID - 10.3390/cells13050409 [doi] PST - epublish SO - Cells. 2024 Feb 27;13(5):409. doi: 10.3390/cells13050409.