Transient receptor potential ion channels (TRPCs) are a superfamily of six transmembrane segment-spanning, gated cation channels. TRPA1 is a TRP-related channel that responds to cold temperatures and pungent compounds and plays a role in both nociceptor and hair cell transduction. It is a transformation-associated gene product in lung epithelia, whereas its protein distribution is primarily restricted to sensory neurons. Blocking TRPA1 may be a therapeutic target for treating cold hyperalgesia caused by inflammation and nerve damage. It is now known that TRPA1 protein is also widely expressed outside of the CNS and is dys-regulated during oncogenic transformation.