Blebbishields and mitotic cells exhibit robust macropinocytosis

Area of Science:

• Cell Biology
• Cancer Research
• Apoptosis

Background:

• Cancer stem cells (CSCs) utilize endocytosis for survival and transformation post-apoptosis.
• Endocytosis facilitates the formation of serpentine filopodia, crucial for constructing blebbishields from apoptotic bodies.
• The role and status of macropinocytosis in blebbishields remain largely uncharacterized.

Purpose of the Study:

• To investigate the presence and function of macropinocytosis in blebbishields formed by apoptotic cancer stem cells.
• To determine if macropinocytosis is essential for the construction of blebbishields.

Main Methods:

• Scanning electron microscopy was employed to visualize blebbishield structures.
• Macropinocytosis assays were conducted to quantify the uptake of extracellular material.
• Inhibitory experiments targeting dynamin-mediated endocytosis and macropinocytosis were performed.

Main Results:

• Blebbishields demonstrate significant macropinocytosis activity.
• Inhibition of dynamin-mediated endocytosis did not impact macropinocytosis in blebbishields or mitotic cells.
• Blocking macropinocytosis did not impede the formation of blebbishields from apoptotic bodies.

Conclusions:

• Apoptotic cancer stem cells exhibit robust macropinocytosis.
• Macropinocytosis is not a critical process for the generation of blebbishields.
• Macropinocytosis may have other, yet undefined, roles in blebbishield biology.