A group of 13-year-old girls will be running five kilometres through the grounds of an Elstree school on Sunday to raise money for a cancer unit.

Adina Sacofsky, of Borehamwood, and Talya Mullish, of Elstree, decided to support their friend Nina Rauch, whose mother, author and journalist Dina Rabinovitch, has breast cancer.

They aim to raise £1,000 by taking part in the Community Fun Run at Haberdashers' Aske's Girls' School, which has been organised by The Jewish Chronicle newspaper.

Nina's mother, who lives in Hendon, is trying to raise £100,000 towards expanding the cancer centre at Mount Vernon Hospital in Northwood - and she has already raised more than £36,000.

Her daughter is delighted that her own fundraising idea has attracted so much sponsorship.

Nina said: "She is trying to raise £100,000 and my nice friends wanted to help. We originally set a £125 target each, and when Talya got £300 we thought we would keep going.

"We've been running around Borehamwood and Hendon. We hope to finish it and not collapse on the way."

The friends, who attend Hasmonean High School, in Mill Hill, will be joined on their run by their friend Tamar Roth, of Golders Green.

Ms Rabinovitch has written of her experience dealing with breast cancer in The Guardian, on her blog, www.dinablog.com, and in her book, Take Off Your Party Dress - When Life's Too Busy for Breast Cancer.

To donate to the appeal, visit www.justgiving.com/dinaspage