Related Experiment Video
Updated: Mar 8, 2026

SA-β-Galactosidase-Based Screening Assay for the Identification of Senotherapeutic Drugs
Published on: June 28, 2019
14-3-3β Depletion Drives a Senescence Program in Glioblastoma Cells Through the ERK/SKP2/p27 Pathway
Sung Bin Seo1,2, Je-Jung Lee3, Hye Hyeon Yun1,2
1Department of Biochemistry, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea.
Abstract:
The induction of senescence in cancer cells has recently been implicated as a mechanism of tumor regression in response to various modes of stress. 14-3-3 proteins are conserved scaffolding molecules that are involved in various cellular functions. Among the seven isoforms, 14-3-3β is specifically expressed in astrocytoma in correlation with the malignancy grade. We investigated the possible role of 14-3-3β in the regulation of senescence induction in A172 glioblastoma cells. The knockdown of 14-3-3β by specific small interfering RNA resulted in a significant change in cellular phenotypes and an increase in cells staining positive for senescence-associated β-galactosidase. Western blotting of the 14-3-3β-depleted A172 cells revealed increased p27 expression and decreased SKP2 expression, while the expression of p53 and p21 was not altered. Subsequently, we demonstrated that ERK is a key modulator of SKP2/p27 axis activity in 14-3-3β-mediated senescence based on the following: (1) 14-3-3β knockdown decreased p-ERK levels; (2) treatment with U0126, an MEK inhibitor, completely reproduced the senescence morphology as well as the expression profiles of p27 and SKP2; and (3) the senescence phenotypes induced by 14-3-3β depletion were considerably recovered by constitutively active ERK expression. Our results indicate that 14-3-3β negatively regulates senescence in glioblastoma cells via the ERK/SKP2/p27 pathway. Furthermore, 14-3-3β depletion also resulted in senescence phenotypes in U87 glioblastoma cells, suggesting that 14-3-3β could be targeted to induce premature senescence as a therapeutic strategy against glioblastoma progression.
Insights
14-3-3 beta protein negatively regulates cancer cell senescence. Depleting this protein induces senescence in glioblastoma cells via the ERK/SKP2/p27 pathway, offering a potential therapeutic target.
Area of Science:
- Oncology
- Cellular Biology
- Molecular Biology
Background:
- Cellular senescence is a key mechanism in tumor regression following stress.
- 14-3-3 proteins are crucial scaffolding molecules with diverse cellular roles.
- 14-3-3 beta (14-3-3β) expression correlates with astrocytoma malignancy.
Purpose of the Study:
- To investigate the role of 14-3-3β in regulating senescence induction in glioblastoma cells.
- To elucidate the molecular pathways involved in 14-3-3β-mediated senescence.
- To assess the therapeutic potential of targeting 14-3-3β for glioblastoma treatment.
Main Methods:
- Utilized small interfering RNA (siRNA) to knockdown 14-3-3β in A172 glioblastoma cells.
- Assessed senescence phenotypes using senescence-associated β-galactosidase staining.
- Analyzed protein expression levels (p27, SKP2, p53, p21, p-ERK) via Western blotting.
- Investigated the role of ERK signaling using MEK inhibitor (U0126) and constitutively active ERK expression.
Main Results:
- 14-3-3β knockdown induced significant cellular phenotypic changes and increased senescence markers.
- Depletion of 14-3-3β led to elevated p27 and reduced SKP2 expression, without altering p53 or p21 levels.
- ERK signaling was identified as a key modulator; 14-3-3β knockdown decreased p-ERK, while MEK inhibition mimicked senescence phenotypes, and active ERK reversed them.
- Senescence was also induced in U87 glioblastoma cells upon 14-3-3β depletion.
Conclusions:
- 14-3-3β acts as a negative regulator of senescence in glioblastoma cells.
- The ERK/SKP2/p27 pathway is critical for 14-3-3β-mediated senescence.
- Targeting 14-3-3β to induce premature senescence presents a promising therapeutic strategy for glioblastoma.
More Related Videos
Related Concept Videos
Negative Regulator Molecules
Inhibition of Cdk Activity
Replicative Cell Senescence
PI3K/mTOR/AKT Signaling Pathway
DNA Damage Can Stall the Cell Cycle
DNA Damage can Stall the Cell Cycle

