MM-129 Counteracts 5-Fluorouracil-Induced Cellular Senescence in Colon Cancer via SIRT1/STAT3 Signaling Pathway

Area of Science:

• Oncology
• Cell Biology
• Pharmacology

Background:

• Cellular senescence is a key factor in colorectal cancer (CRC) development and progression.
• 5-fluorouracil (5-FU) chemotherapy can induce senescence, potentially leading to chemoresistance and tumor recurrence in CRC.
• Investigating novel senotherapeutics is crucial for improving CRC treatment outcomes.

Purpose of the Study:

• To investigate the effect of 5-FU on colon cancer cell senescence.
• To evaluate the potential of MM-129 (pyrazolo[4,3-e]tetrazolo[4,5-b][1,2,4]triazine sulfonamide) to antagonize 5-FU-induced senescence.
• To elucidate the underlying molecular mechanisms of MM-129's senotherapeutic activity.

Main Methods:

• Senescence was assessed via senescence-associated β-galactosidase (SA-β-gal) and p21 expression.
• Key senescence-associated secretory phenotype (SASP) cytokines (IL-6, TNF-α) and E-cadherin (CDH1) were measured.
• The SIRT1/STAT3 pathway was analyzed to understand MM-129's mechanism of action.
• Experiments were conducted in vitro, in zebrafish xenografts, and in DLD-1 and HT-29 mouse xenografts.

Main Results:

• MM-129 effectively counteracted 5-FU-induced senescence in colon cancer models.
• MM-129 reduced p21 levels and the number of SA-β-gal-positive cells in various models.
• MM-129 suppressed SASP cytokines (IL-6, TNF-α), restored E-cadherin (CDH1), and modulated the SIRT1/STAT3 pathway.

Conclusions:

• MM-129 demonstrates potential as a novel senotherapeutic agent for colorectal cancer.
• By targeting the SIRT1/STAT3 axis, MM-129 may suppress SASP and pro-survival signaling, aiding senescent cell clearance.
• Combining senotherapeutics like MM-129 with conventional therapies offers a promising avenue for enhancing CRC treatment efficacy.