Precise control over the oxygen conditions within the Boyden chamber using a microfabricated insert.

Area of Science:

• Biomedical Engineering
• Cancer Research
• Cell Biology

Background:

• Cell migration is crucial for cancer metastasis and is linked to tumor hypoxia.
• The Boyden chamber is a common tool for in vitro cell migration assays.
• Current hypoxic chambers lack precise spatial and temporal control over oxygen levels.

Purpose of the Study:

• To develop a novel microfabricated polydimethylsiloxane (PDMS) device for enhanced control of oxygenation in Boyden chamber assays.
• To investigate the effects of continuous and intermittent hypoxia on MDA-MD-231 breast cancer cell migration.

Main Methods:

• A microfabricated PDMS device was integrated with a standard Boyden chamber.
• The device utilized a Parylene-C coating for improved oxygen equilibration and stability.
• MDA-MD-231 cells were exposed to various oxygen conditions (normoxia, continuous hypoxia, 0-21% IH, 5-21% IH) and their migration was measured.

Main Results:

• The PDMS device achieved 1% oxygen equilibration within 20 minutes.
• Continuous hypoxia and 0-21% intermittent hypoxia (IH) downregulated cell migration compared to normoxia.
• Exposure to 5-21% IH significantly increased cell migration relative to normoxic and other hypoxic conditions.

Conclusions:

• The developed PDMS device offers precise and rapid control over oxygen levels for in vitro hypoxic studies using the Boyden chamber.
• The findings highlight that specific intermittent hypoxia regimens can promote cancer cell migration, a critical factor in metastasis.