Gemcitabine therapeutically disrupts essential SIRT1-mediated p53 repression in atypical teratoid/rhabdoid tumors

Area of Science:

• Neuro-oncology
• Developmental Biology
• Molecular Oncology

Background:

• Atypical teratoid/rhabdoid tumors (ATRTs) are aggressive pediatric embryonal central nervous system tumors with poor outcomes.
• Novel therapeutic strategies are urgently needed for ATRTs.

Purpose of the Study:

• To investigate the therapeutic potential of gemcitabine against ATRTs.
• To elucidate the molecular mechanisms underlying gemcitabine's efficacy in ATRTs.

Main Methods:

• Utilized patient-derived ATRT cell cultures and xenograft models.
• Performed gene expression and protein analyses to identify molecular targets.
• Assessed gemcitabine's effect on cell viability, signaling pathways (SIRT1, NF-κB, p53, SHH/GLI2), and tumor growth in vivo.

Main Results:

• ATRTs demonstrated selective sensitivity to gemcitabine.
• Gemcitabine induced sirtuin 1 (SIRT1) degradation, activating nuclear factor κB (NF-κB) and p53, leading to cell death.
• Gemcitabine treatment caused GLI2 translocation, enhancing sensitivity in SHH-subtype ATRTs.
• Gemcitabine significantly increased median survival (>30%) and generated long-term survivors in ATRT xenograft models.

Conclusions:

• Gemcitabine exhibits significant anti-tumor activity against ATRTs.
• The mechanism involves SIRT1 degradation and subsequent activation of NF-κB and p53 pathways.
• Gemcitabine represents a promising therapeutic agent for ATRTs and may be incorporated into future treatment regimens.