Last year, I learned that James Rouse, a good friend of mine, had been diagnosed with an aggressive brain tumour.

I am grateful for the opportunities I have had (and still have) to hang out with James. His poignant reflections on the likelihood that his life will be abbreviated by his illness have not dominated our conversation, but they have been an ever-present background noise.

Life is full of unfairness, and James prefers to think of his life in terms of the blessings he has enjoyed rather than his current misfortune. He is not bitter, and he is not angry.

Being several steps removed from his circumstances though, I am bitter and angry at what he and his family are going through.

I am powerless to help James, but that does not mean there's nothing I can do.

With that in mind, I applied for and secured a place as one of the runners for the charity Brain Tumour Research at this year's London Marathon, and I am grateful to them for providing me with an opportunity to raise money for the vital work they do.

As one of this year's participants for Brain Tumour Research, I was added to a WhatsApp group of the other runners, and I have been absolutely awed by their stories. Out of tales of individual tragedy, they have been inspired to step up, and I am proud to be among them.

At our lowest moments, the struggle against cancer can feel hopeless but, if we pay attention, we should notice the difference being made by research. The progress is astonishing, and many people who are alive today wouldn't be if it weren't for the generosity of those who have helped to fund the research.

Someone asking for you to sponsorship because they are running a marathon provides an impetus for you to play your part in this fund-raising effort.

So, if, after reading this, you want to support this vital research, please do it now... you know how this works, if you don't, you probably won't ever get round to it.