Making new cells - The engine of the cell cycle

checkpoints in the cell cycle There are several steps in the cell cycle, and specific molecules control the switch from one step to the next. They must be activated and then destroyed at the right time and in the right sequence, in order to drive the process.

These molecules – known as CDKs and cyclins – are crucial for the cell cycle to run smoothly. They act at important checkpoints, where the cell makes sure everything is in order before proceeding.

In 2001, Cancer Research UK scientists Professor Paul Nurse and Dr Tim Hunt were awarded the Nobel Prize for Physiology or Medicine for first discovering these molecules.

Over the years, our scientists have made monumental strides in understanding the molecules that control the cell cycle.

From yeast to humans

Studying dividing cells

Breast cancer cells dividing We funded the work of Professor Paul Nurse for over 20 years. By studying how yeast cells divide, he made the pioneering discovery in the 1980s that CDKs control how cells move from one step in the cell cycle to the next.

Around the same time, another of our eminent scientists, Dr Tim Hunt, discovered that cyclins are also central to the cell cycle. By studying sea urchin egg cells, he showed that cyclins are produced in large quantities and then destroyed at particular points in the cell cycle. He also found that cyclins need to bind to CDKs during cell division.

So CDKs are like the engine of the cell cycle, driving it forwards, and cyclins are the gearbox – regulating the timing and the speed. This cutting-edge research was a real turning point in our understanding of cell division and has opened up promising avenues for cancer treatment.

Researchers have found that levels of CDKs and cyclins are raised in several types of cancer, including breast cancer and malignant brain tumours. Professor Paul Workman, director of the Cancer Research UK Centre for Cancer Therapeutics at The Institute of Cancer Research, is developing and testing molecules to block CDKs. These studies could lead to powerful cancer drugs in the future.

In Cambridge, Professor Jonathon Pines has pioneered the use of fluorescence microscopy (using laser or ultraviolet light and powerful microscopes) to study the movement of cyclins, CDKs and other molecules within living cells. He has made many important discoveries in this area, helping us to understand the cell cycle in healthy cells and in cancer.

Faults in the cell cycle underpin all forms of cancer, so understanding this fundamental aspect of cancer biology is vital if we are to beat cancer. The work of our world-class scientists will help us understand more about how cells divide and what goes wrong in cancer. This will lead to new strategies for tackling many types of cancer in the future.