Credit: Dimitrios Kambouris/

Jennifer Aniston has bared her chest in the name of breasts!

At Lifetime's Five premiere in NYC on Monday, Aniston ditched her regular red-carpet LBD for a sexy Dolce & Gabbana pantsuit that included a cleavage-baring vest that showed off her lacy black bra.

Joined by her serious beau, Justin Theroux, inside the theatre, the 42-year-old actress had a lot to celebrate, like her behind-the-camera debut -- she directed one of the short movies in the emotional film that depicts the lives of different breast cancer sufferers.

An insider tells Us Weekly, "When the film was over, Justin was the first to stand and clap and cheer. He had his hand on her leg the entire movie. At the reception, Justin seem like a very good boyfriend and was lovingly looking at her. He seemed very proud of her and was smiling a lot." See more pics of Jen and Justin at the premiere from PopSugar.

Aniston wasn't the only star who bared her chest on the red carpet -- Alicia Keys, who also directed one of the films, also wore a peek-a-boo black bra underneath a tailored blazer.