Growth Factors and Cancer

The fundamental difference between cancer and healthy cells is rapid, uncontrolled multiplication. This results from excessive activity or numbers of growth factor receptors. Modern targeted cancer treatments were developed against these receptors. Let us explore growth factor receptors, important in every aspect of cancer.

What Is a Receptor?

For vital functions, cells must receive external stimuli such as hormones and growth factors at their surface and transmit the message inside. Surface structures binding external molecules are called receptors . Some receptors are not on the surface but inside the cytoplasm or nucleus (such as testosterone receptors).

Receptors binding growth factors that support cell division are called growth factor receptors . The figure below illustrates how a cell-surface growth factor receptor works.

A growth factor in the extracellular microenvironment binds its receptor and activates it. The receptor’s intracellular portion contains a kinase enzyme region. These regions activate a series of intracellular proteins. Proteins transmit signals received from outside to the nucleus. At specific regions of DNA, binding proteins activate genes involved in proliferation, differentiation and other vital activities.

One Cause of Cancer: Continually Active Receptors

Normally, growth factor receptors activate under certain circumstances to regulate proliferation. However, accumulating DNA damage causes receptor changes, making them continuously active and sending the cell a continuous proliferation signal , resulting in cancer development.

Why Are Growth Factor Receptors So Important in Cancer?

• In the tumor microenvironment , growth factors occur in greater than normal amounts. They bind receptors and trigger aggressive cancer growth. In addition, in genes responsible for producing growth factor receptors, mutations also keep the receptors continuously active.
• Growth factor receptor mutations are generally associated with aggressive cancer growth. Clinically, disease course is poor in such cases.
• Growth Factor Receptors in Cancer:
  • Epidermal growth factor receptor - EGFR,
  • Insulin-like growth factor - IGFR,
  • Transforming growth factor receptor - TGF,
  • Vascular Endothelial Growth Factor Receptor - VEGFR,
  • Platelet derived growth factor receptor – PDGFR.
• With advances in genetic testing techniques , mutations in receptor-producing genes have been identified and drugs designed against them. Targeted medicines bind mutated receptors and growth factors, preventing aggressive cancer growth.

Related Topic

WHAT IS CANCER? Why and How Does It Develop? The Entire Process in Brief!