For the fourth time, all four broadcast networks will put aside their competition for television ratings to focus on the fight against cancer and help fund research with a Stand Up To Cancer special. The networks have aired the commercial-free hour every two years, beginning in 2008.

Actress Gwyneth Paltrow will be back for a second year to executive produce, along with Tenth Planet Producers president Joel Gallen, the networks said in a statement. Paltrow, Gallen and the SU2C Production Team will put together a unique show with performances from musicians and appearances by film and television stars.

In addition to ABC, Fox, NBC and CBS carrying it, several cable networks will as well. Showtime, HBO, ESPNews, MLB Network, E!, Encore, Starz, TNT and National Geographic Channel are just a few of the cable networks that signed up to carry it. The special will air on Friday, Sept. 5, live from Los Angeles’ Dolgy Theater.

The four major English Canadian networks - CBC, City, CTV and Global - will also carry. Money raised through those broadcasts will go directly to research and education programs in Canada.

“Cancer profoundly touched my life when I lost my father to the disease twelve years ago, and Stand Up To Cancer gives me a powerful platform to fight for a cause that I’m passionate about,” Paltrow said in a statement. “I am thrilled to join Joel Gallen to executive produce the Stand Up To Cancer telecast again this year, and honored to continue standing up in my father’s memory.”

This year will also have an added social media element, as so many special TV events do lately. Celebrities will interact with fans, encouraging them to donate by calling, texting or visiting standup2cancer.org.

“When we launched Stand Up To Cancer, our goal was to approach the struggle against cancer in a different way. Just six years into this movement, the incredible generosity of our donors -- of every level -- has enabled major progress in developing new treatments,” Katie Couric, a co-founder of SU2C, added. She said that the show gives viewers a unique way to see how medical science has progressed and that they can still help scientists continue their research.

Couric appeared on Today this morning to announce the new special.

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