Related Experiment Video
Updated: Jun 21, 2026
06:54
Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells
Published on: October 27, 2020
TGF-beta: a new role for an old AktTOR
Pankuri Goraksha-Hicks1, Jeffrey C Rathmell
1Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA.
Developmental Cell
|July 22, 2009
Summary
High glucose levels (hyperglycemia) can drive cell growth. This study reveals that hyperglycemia activates the mTOR pathway, promoting cell hyperplasia, a key event in diseases like cancer and diabetes.
Area of Science:
- Cellular biology
- Metabolism
- Pathophysiology
Background:
- Nutrient overabundance is a known factor in cellular hypertrophy.
- The precise mechanisms linking nutrient excess to pathological cell growth remain largely undefined.
- Hypertrophy is a significant event in diseases such as diabetes and cancer.
Purpose of the Study:
- To elucidate the mechanisms by which nutrient overabundance, specifically hyperglycemia, influences cell growth.
- To establish a novel model connecting metabolic status with cellular proliferation.
- To investigate the role of the transforming growth factor-beta (TGF-beta) and mTOR pathways in hyperglycemia-induced cell growth.
Main Methods:
- Utilized a model system to study the effects of hyperglycemia on cellular processes.
- Investigated the activation pathways of mTOR signaling.
- Examined the interplay between TGF-beta signaling and metabolic cues.
Main Results:
- Demonstrated that hyperglycemia directly promotes cellular hyperplasia.
- Showed that hyperglycemia increases the activation of the mTOR pathway in a TGF-beta-dependent manner.
- Established a link between metabolic state and cell growth regulation.
Conclusions:
- Hyperglycemia can induce cellular hyperplasia by activating the mTOR pathway.
- The findings provide a new model for understanding how metabolic dysregulation contributes to diseases characterized by abnormal cell growth.
- This research highlights potential therapeutic targets for conditions involving cellular hypertrophy and hyperplasia.
Related Concept Videos
01:16TGF - β Signaling Pathway
The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
01:22Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...
01:26Introduction to Actin
Actin is a highly conserved cytoskeletal protein found abundantly in eukaryotic cells. It constitutes 10% weight of the total cellular protein in muscle cells, while in non-muscle cells, it is lower and makes up around 1–5 percent of the total cell protein. Actin found in the unicellular amoebae and complex multicellular animals is around 80% similar, demonstrating their conservation over a billion years of evolution. Actin coding genes are conserved within species and across different species.
01:58Mechanical Protein Functions
Proteins perform many mechanical functions in a cell. These proteins can be classified into two general categories- proteins that generate mechanical forces and proteins that are subjected to mechanical forces. Proteins providing mechanical support to the structure of the cell, such as keratin, are subjected to mechanical force, whereas proteins involved in cell movement and transport of molecules across cell membranes, such as an ion pump, are examples of generating mechanical force.
01:00Enzyme-linked Receptors
Enzyme-linked receptors are proteins that act as both receptor and enzyme, activating multiple intracellular signals. This is a large group of receptors that include the receptor tyrosine kinase (RTK) family. Many growth factors and hormones bind to and activate the RTKs.
Neurotrophin (NT) receptors are a family of RTKs, including trkA, trkB, and trkC (tropomyosin-related kinase) receptors. TrkA is specific for nerve growth factor (NGF), neurotrophin-6, and neurotrophin-7. TrkB binds...
Neurotrophin (NT) receptors are a family of RTKs, including trkA, trkB, and trkC (tropomyosin-related kinase) receptors. TrkA is specific for nerve growth factor (NGF), neurotrophin-6, and neurotrophin-7. TrkB binds...
02:14GTPases and their Regulation
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...
Large G-proteins, also known...