Murine Perineural Invasion Model: Generating an In Vivo Model to Simulate Perineural Invasion in Mouse Sciatic Nerve

Perineural invasion is a rare metastatic phenomenon wherein cancer cells metastasize away from the site of origin to invade the perineural space within the nerves. The nerve microenvironment provides a suitable environment for cancer growth and proliferation.

To simulate perineural invasion in vivo, prep an anesthetized mouse in the prone position. Make a small, parallel incision below the thigh bone - femur. Separate the thigh muscles to reveal the underlying sciatic nerve - the largest and most easily accessible nerve in the body.

The sciatic nerve originates in the lower spine and runs through the pelvic muscles to each leg. It relays signals for coordinated movement of lower limbs. Next, remove the surrounding muscles from the nerve and pull it outwards using a sterilized spatula for injection support.

Now, take a syringe filled with the cancer cell suspension and inject it parallelly into the nerve. A visible bulge in the nerve confirms a successful injection, while any leakage around the injection site indicates a failed attempt. Briefly, allow the cells to stabilize within the nerve.

Then, gently retract the needle and reposition the muscles. Subsequently, suture the incision. Allow the mouse to recover. Eventually, the cancer cells start migrating from the injection site towards the spinal cord, confirming perineural invasion.