Statins have definitely revolutionised medicine – and not just in the cardiovascular field. They don’t just lower your cholesterol, or just smooth out the vascular endothelium, or have benefits with inflammation – it seems that they have some protective effect against cancer as well – in this case, colorectal cancer.
OK, so what you’re looking at above is the mevalonate pathway (also known as the HMG-CoA reductase pathway) – and you can see where statins interfere. Downstream of this, a collection of pyrophosphates (isoprenoids) are formed, which have a significant role in the function of cellular proteins. Some of these proteins play a key part in growth factor signalling and are found in tumours – and because cholesterol is important in cell membranes – statins have a role in preventing malignancy.
Does this translate to a clinical reality? The authors of this meta-analysis looked at a collection of 4002 articles, narrowing it down to 32 after filtering out the irrelevant articles, and found that there is a small but significant decrease in risk in rate of CRC with chronic statin use (about 8%) – but this is only when all the studies are pooled together, the RCTs on their own didn’t reach statistical significance.
It’s all not very strong and definitely needs more definitive work – read all about it here.