Cancer cells, with their unlimited, rapid growth, often consume more than healthy cells. Scientist have considered exploiting this feature to trick cancer cells into ‘eating’ anti-cancer drugs. This would make the drugs more effective and reduce their side effects, as healthy cells would tend not to eat them. One approach is to trick tumour cells into a ‘starved’ state so they more readily consume the drug.

Some immune system cells use endocytosis to engulf cancer cells. Treatments that enhance this ability could encourage the body’s own cells to attack tumours.

Most animal, plant and fungal cells contain mitochondria; one of the compartments within cells called organelles, which carry out specialist functions. The main role of mitochondria is to provide energy to run the cell. Most DNA is in the cell nucleus, but mitochondria have their own DNA. One suggestion is that mitochondria may have in the distant past been free-living bacteria that were captured by other cells through a process similar to endocytosis. The combined cell proved advantageous, and the mitochondria evolved to become an essential organelle of other organisms. The same could be true of chloroplasts, organelles of plants which capture energy from the sun and also have their own DNA. Scientists still need to find definite proof of the endocytosis theory.

A diet with too much of the fat cholesterol is typical of many industrialised, wealthy societies and leads to excess of harmful LDL cholesterol in the blood. This causes some macrophage cells of the immune system to consume too much LDL cholesterol through endocytosis. Overconsumption kills the cells and attracts more macrophages to clear up their remains. Eventually this leads to an inflammation reaction encouraging the build-up of debris that narrows arteries, a hallmark of cardiovascular disease. Gaining a deeper understanding of the endocytosis process, the environmental factors that affect regulation of the mechanism and how it contributes to disease will help in developing new approaches to prevent and treat this disease, which is on the rise worldwide.