Aherne, who has starred in The Mrs Merton Show, The Royle Family and The Fast Show, is recovering from treatment for lung cancer.
Macmillan Cancer Support says the star will speak at an event aimed at helping to improve care in Manchester on the 26th June.
Aherne said of the appeal: "I've had cancer and my brother's had cancer and we know how it affects people."
"They’ve asked me to get involved and I’m really glad that I can do my bit to encourage Manchester people to speak up about where things do go wrong with cancer care."
Caroline Aherne as Denise in The Royal Family which she starred in and wrote
Advertisement
Aherne has previously been treated for eye cancer along with her brother when she was a child.
Aherne and her brother, Patrick, now 52, were both born with a rare cancer of the retina and she was left almost blind in one eye as a result.
She also revealed that she had been treated for bladder cancer in the past.
During the 1990s she suffered from depression and drink problems following the death of her father and the breakdown of her marriage and in 1998 she attempted suicide.
She moved to Australia that year and then back to England in 2002.
She is currently working as the narrator on Channel 4's Gogglebox and said she hopes to continue for "as long as Gogglebox want me."
