When cells go wrong and cause cancer

When a few gene in one cell become damaged, or mutated, this can lead to cancer. These faulty genes, or gene mutations, may tell the cell to multiply at the wrong time, or in the wrong place. This is how cancer starts. Sometimes the cell-cycle checkpoints themselves are faulty or the damaged cells are able to side-step them.

This image shows a prostate cancer cell multiplying to form two cells. If abnormal cancer cells are allowed to keep on multiplying they will eventually form a mass of faulty cells, called a tumour.

A tumour takes up a lot of space and can put pressure on surrounding tissues and organs, stopping the body from working properly.

Sometimes cancer cells can break off from the main tumour and enter the bloodstream.This allows the cancer cells to travel around the body and may lead to a second cancer forming in another place - a process that is called metastasis.

Cancer can also spread via the lymphatic system. Lymph is a clear fluid that circulates around the body’s tissues and contains the white blood cells. Cancer cells can travel by the lymphatic system and often end up at the lymph nodes, which are located at different sites in the body. Doctors will often check these nodes to see if cancer has spread there.

You can read more about the causes of cancer using the links below.

Events can lead to cancer

All images were kindly provided by the EM Unit at the London Research Institute and the Science Photo Library.