Targeted Therapy

Targeted therapy uses drugs to target specific molecules (for example, proteins) inside cancer cells or on their surface. Targeted therapy is also called molecularly targeted therapy. It is used to:

• slow the growth of cancer
• destroy cancer cells
• relieve symptoms caused by cancer

There are different types of targeted therapy drugs. They each work differently depending on what molecule (gene or protein) the drug is targeting. A treatment is chosen based on the types of proteins or molecules made by a person’s tumour. Targeted therapy drugs target mutated proteins or mutated genes in cancer cells. This allows doctors to tailor cancer treatment for each person. Targeted therapy is an important part of personalized medicine(also known as precision medicine) which uses information about a person’s genes and proteins to prevent, diagnose and treat cancer.

How targeted therapy works?

Targeted therapy targets the molecules that send signals that tell cancer cells to grow or divide. By targeting these molecules, the drugs act on the cells internal environment, block their signals and stop the growth and spread of cancer cells while harming normal cells as little as possible.

Important to note is that targeted therapy only works if a cancer cell has the gene or protein target that the drug is trying to block. So it isn’t given to everyone. People who are planned to be given targeted therapy have to first undergo special tests to test for these targets. If that target is present in a person’s tumour, the drug against that target can be given. But even if a person’s cancer cell has a certain target, it doesn’t mean that targeted therapy will surely work. This is because the protein or gene that the treatment is destined to target may only be a part of the reason that the tumour is growing.

Targeted therapy may cure cancer by itself or it may be very useful when combined with other types of cancer treatment such as surgery, chemotherapy or radiation therapy.

Types of Targeted Therapy

Most targeted therapies are either small-molecule drugs or monoclonal antibodies.

• Small-molecule drugs: are small enough to enter cells easily, so they are used for targets that are inside cells.
• Monoclonal antibodies: also known as therapeutic antibodies, are proteins produced in the lab. These proteins are designed to attach to specific targets found on cancer cells. Some monoclonal antibodies mark cancer cells so that they will be better seen and destroyed by the immune system. Other monoclonal antibodies directly stop cancer cells from growing or cause them to self-destruct. Still others carry toxins to cancer cells.

How does targeted therapy work against cancer?

• Helps the immune system destroy cancer cells
• Stop cancer cells from growing.
• Stop signals that help form blood vessels
• Causes cancer cell death
• Deliver cell-killing substances to cancer cells

These targeted therapies are latest medicines developed for treatment of cancer. They go and kill only cancer cells and hence are very effective. You should ask your doctor about these medications during counselling sessions. Moreover, these medicines are mostly oral tablets hence they are easy to take for the patients.