Polyphyllin II Induces Apoptosis in Fibrosarcoma Cells via Activating Pyruvate Kinase M2

Area of Science:

• Biochemistry
• Molecular Biology
• Cancer Research

Background:

• Aerobic glycolysis is crucial for tumor cell proliferation, supplying energy and mass.
• Pyruvate kinase M2 (PKM2) plays a vital role in aerobic glycolysis and is a target for anticancer drug development.
• Polyphyllin II (PP2), a steroidal saponin, exhibits toxicity to cancer cells and may interfere with PKM2 activity.

Purpose of the Study:

• To investigate whether PP2 affects PKM2 activity and its downstream effects.
• To elucidate the mechanism by which PP2 impacts cancer cell metabolism and survival.
• To evaluate the therapeutic potential of PP2 in fibrosarcoma.

Main Methods:

• Assessed PP2's effect on recombinant and intracellular PKM2 activation and oligomeric state.
• Measured nuclear PKM2 content and mRNA levels of downstream genes (Glut1, LDHA, MYC).
• Investigated PP2-induced oxidative stress, antioxidant protein expression, mitochondrial dysfunction, and apoptosis in HT-1080 cells.

Main Results:

• PP2 was identified as a novel PKM2 agonist, activating both recombinant and intracellular PKM2.
• PP2 decreased nuclear PKM2, suppressed its kinase function, and inhibited downstream gene expression.
• PP2 induced oxidative stress, downregulated antioxidant proteins, caused mitochondrial dysfunction, and promoted apoptosis in HT-1080 cells.
• PP2 reduced HT-1080 cell proliferation and migration.

Conclusions:

• PP2 acts as a PKM2 agonist, modulating glycolysis and inducing cancer cell apoptosis.
• Targeting the glycolysis pathway via PP2 offers a novel mechanism for fibrosarcoma therapy.
• PP2 demonstrates potential for further development as an anticancer agent for fibrosarcoma.