Cancer arises from the uncontrolled growth and division of cells, and is caused by the cooperation of mutations in DNA that activate genes that push cell division, and suppress natural anti-cancer mechanisms. Currently in the UK, around 275,000 people per year are diagnosed with cancer and, of these, around 150,000 die. For the 400 people who die each day from the disease, treatment is largely ineffective and offers at best an extension of life, rather than a cure.
Current anti-cancer therapies are primarily based on trying to inhibit cancer cell growth, causing cancer cells to die, or a combination of both. Frequently, initial treatments may appear to be successful, but the disease re-occurs at a later date. Understanding how this happens, and what controls the ability of cancer cells to spread throughout the body, is a crucial aspect of cancer research.
Recent advances in our understanding of cancer have revealed why many current treatments may be ineffective. Within any tumour, there may be many different kinds of cancer cell, only some of which are targeted by a particular treatment. Although a therapy may be successful in killing some of these sub-populations of cells, others survive and these then go on to kill the patient.
The discovery of normal adult stem cells, able to self-renew and regenerate damaged tissue, has led to the idea that cancer may either originate from adult stem cells or contain stem cell-like cells that are self renewing, resistant to therapy and able to seed new tumour growth.
Identifying the stem cell-like cells within cancers and understanding their properties will be crucial if effective anti-cancer therapies are to be developed, since different populations of cancer cells within a tumour can switch back and forth between one cells that divide rapidly but do not invade, and stem cell-like cells that divide slowly but are highly metastatic.
Invasive stem cell-like cells may also have other special properties, like the capacity to evade the immune system and be highly resistant to chemotherapy.
Work in Oxford is directed towards understanding the properties of cancer stem cell-like cells, and finding ways in which they may be targeted in the development of effective anti-cancer strategies.