Targeted Therapy for Cancer

January 24, 2024

3 min read

Targeted therapies are cancer treatments designed to treat cancers by targeting the genetic mutations or changes that turn healthy cells into cancer cells.

What is targeted therapy?

Targeted therapy is a cancer treatment that uses drugs or substances to attack specific cancer cells.

Cancer cells need protein to grow, multiply, and spread. Considered the foundation of precision medicine, targeted therapy attacks proteins that control how cancer cells grow, spread, and divide.

Targeted therapy can be used by itself or in combination with radiation therapy, chemotherapy, or surgery.

Types of Targeted Therapy Drugs

Targeted therapy drugs are of two primary types.

Small molecule drugs

They are small enough to enter cells easily and interfere with the molecules inside the cell. They are also used to target the molecules on the cell's surface.

Monoclonal antibodies

They are proteins produced in the lab that attach to targets found on the cancer cells. Also known as therapeutic antibodies, the monoclonal antibodies mark cancer cells to be better seen and destroyed by the body’s immune system.

While some monoclonal antibodies cause cancer cells to self-destruct, others deliver toxins directly to the cancer cells.

Diseases Treated with Targeted Therapy

Targeted therapy is not suitable for all patients and all types of cancers. Certain cancers, like myelogenous leukemia (CML), have targets for certain drugs. Those cancers can be treated using the specific drugs.

To use targeted therapy, tumors must be tested to see if they have any targets for which a drug exists. Biometric testing is done to test cancers for targets and to choose the necessary treatment.

Currently, targeted therapy is used to treat cancers like:

Lung cancer
Kidney cancer
Melanoma
Leukemia
Brain cancer
Prostrate cancer
Myeloma
Breast cancer
Gastrointestinal cancers
Head and neck cancers
Mesothelioma

How does targeted therapy work against cancer?

Targeted therapy can treat cancer in the following ways:

Stops cancer cells from growing and dividing without order. Some targeted therapies block proteins, slowing the process of uncontrollable growth in cells.
Stops signals that form blood vessels in tumors. Tumors grow in size by sending signals to form new blood vessels, a process known as angiogenesis. Some targeted therapies interfere with the signals to prevent blood vessels from forming, keeping the tumors small.
Assists the immune system in destroying cancer cells. Certain targeted therapies boost the immune system to work better against cancer, while others mark cancer cells, making it easier for the immune system to locate and destroy them.
Causes death of cancer cells potentially. Some targeted therapies cause cancer cells to go through cell death, a process called apoptosis.
Delivers cell-killing substances to cancer cells. Some monoclonal antibodies combine with toxins, chemotherapy drugs, or radiation while attaching to the targets on the cancer cells. The cancer cells take up the toxic substances, causing them to die.
Starves cancer of hormones that cause growth. Certain prostate and breast cancers thrive on hormones. Some hormone therapies prevent the body from making certain hormones, while others deter hormones from acting on cancer cells.

Drawbacks of Targeted Therapy

Targeted therapy has certain drawbacks.

Cancer cells can become resistant to targeted therapy.
Developing targeted drugs for cancer treatment can be challenging because of the target’s structure or their function in the cell.