Promotion of cellular senescence by THG-1/TSC22D4 knockout through activation of JUNB

Area of Science:

• Oncology
• Cell Biology
• Molecular Biology

Background:

• Cellular senescence induction is a key cancer treatment strategy.
• Cancer cells can resist senescence by inactivating tumor suppressors.
• Developing methods to induce senescence in cancer cells is crucial for new therapies.

Purpose of the Study:

• To investigate the role of TSC-22 homologous gene-1 (THG-1, also known as TSC22D4) in cellular senescence suppression.
• To identify pathways involved in THG-1-mediated senescence regulation.
• To explore THG-1 as a potential target for cancer therapy.

Main Methods:

• CRISPR/Cas9 gene editing to create THG-1 knockout (KO) esophageal tumor cells.
• Analysis of cell proliferation and senescence markers in THG-1 KO cells.
• siRNA-mediated knockdown of JUNB to assess its role in P21(CDKN1A) transcription and senescence.

Main Results:

• THG-1 KO cells showed delayed proliferation and induced cellular senescence.
• Elevated expression of CDK inhibitor P21(CDKN1A) was observed in senescent cells.
• JUNB pathway was identified as critical for P21(CDKN1A) transcription; JUNB knockdown reduced P21(CDKN1A) mRNA and senescence in THG-1 KO cells.

Conclusions:

• THG-1 (TSC22D4) suppresses cellular senescence in esophageal tumor cells.
• The JUNB pathway is essential for P21(CDKN1A) induction and senescence in THG-1 deficient cells.
• Targeting THG-1 presents a novel approach for inducing cancer cell senescence.