A Molecular Overview of Cancer

A Basic Science Perspective of the Challenges Facing Cancer Researchers

The Issue

 Cancer is a disease that has touched the lives of millions of people around the world.  Despite billions of dollars in spending and countless research hours, a cure has yet to be developed.  For many, this concept may be difficult to fathom.  What is the delay?  Why have scientists not figured this out?  Although these are simple questions, the answers are not so straightforward.  A vast amount of literature is available on the diagnosis and physiological understanding of cancer.  However, this article will overview the less common, molecular field of cancer.  This perspective will shed some light on what the current challenges are and why progress appears slow.

Basic Overview of Cancer

Cancer can be defined as the deregulated growth of a cell.  Normally, cells grow for a certain amount of time and then die.  However, in the case of cancer, cell growth is continuous.  As the cancer cell growth continues, the group of cells creates an ‘island’ in the body and develops a novel supply of nutrients from the blood.  This process, angiogenesis, generates new blood vessels that provide the group of cancer cells with all the necessities to support further growth.  This cancer island is then protected from the body’s defence system and is free to continue growth without disruption.  However, this concept begs the question, how did the cells become deregulated in the first place? This question is best addressed through basic molecular biology.

Molecular Biology of Cancer

Proteins predominantly control the various biological functions of a cell (growth, death, differentiation etc).  The proteins themselves are subject to tight regulation to avoid adverse effects on a cell such as deregulated growth.  This protein regulation occurs in many forms such as timely/tissue specific expression of the protein from the gene that encodes for it, modifying the protein to turn it on and controlling binding to targets that allow the protein to function.  These different forms of regulation keep an active protein under control so that a task starts and stops exactly when/where required.  For example, if a cell needs to grow, a protein(s) will become activated in order to allow the growth process to occur.  However, if this protein becomes over active, the cells will continue to grow endlessly and a potential tumour will arise.  This illustrates the need for a tight regulation of protein activity.