Some additional context would be helpful, but it appears that this would mean that the person in question has/will "appear in advertisements" (presumably on television).

More context is needed

(1) If it's someone who can act (an actor, a professional), then you can safely say "act in a commercial".

"acted in commercials" site:uk (UK sites)
http://tinyurl.com/3vjnz2

"acted in commercials" site:-uk (non-UK sites)
http://tinyurl.com/4m87j4


(2) If the participant probably doesn't do "real" acting then you can use a very popular idiom of "to be cast in...".
Examples: animals, little children and amateur actors often "are cast" rather than "act".
But you can use "to be cast" also about actors because it's more general.
Although its dictionary meaning is "to be chosen for a role" (etc.), what matters is often the result, i.e., "was cast..." would quite certainly mean that they indeed did act/appear in the commercial.


"Tiffani was quickly cast in commercials for The Peaches and Cream Barbie Doll."
http://photo.leechvideo.com/Tiffani-Thiessen

"Diannah Morgan, who is continually cast in commercials"
http://www.actingintuitive.com/pages/FAQs.htm

"Andrew Cast in TV Advert
[...] a quick congratulations note to one of my clients Andrew Elston who after working really hard over the past 7 months with me has today been cast in a TV advertisment."
http://www.theheatfitness.co.uk/articlelive/blogs/7/Andrew-C...

"Notice the number of decidedly chubby actors (and I'm not talking Kirstie Alley) who are sympathetically cast in commercials?"
http://www.lacitybeat.com/cms/story/detail/commercials_r_us/...

"31 of Houston's finest actors were cast in the latest set of Time Warner commercials. "
http://www.onlyinhouston.org/en/releases/search.asp?category...

"Moose and Enzo also appeared with Frankie Muniz in the 2000 feature film My Dog Skip. Enzo was cast as Skip in the feature film My Dog Skip; Moose played the older Skip in a few scenes."
http://en.wikipedia.org/wiki/Moose_(dog_actor)

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"cast
[...]
12
a. To choose actors for (a play, for example).
b. To assign a certain role to (an actor): cast her as the lead.
c. To assign an actor to (a part): cast each role carefully."
http://www.bartleby.com/61/65/C0146500.html