Technology & Innovation

Targeted Therapies

Perhaps the most exciting area of cancer treatment progress has been the development of targeted therapies. These drugs are different than standard chemotherapy in a few ways.

Unlike chemotherapy, which usually attacks all rapidly dividing cells in a patient’s body, targeted therapies act on specific molecules that are important to cancer growth and spread. Targeted therapies don’t always kill cancer cells, but instead, they may simply interfere with cancer cells’ ability to grow or replicate. Because targeted therapies are not necessarily designed to kill cancer cells, they often have far less toxicity and far fewer side effects.

At Mount Sinai, our cancer experts use a variety of targeted therapies to effectively treat different types of cancers. Our growing arsenal of targeted therapies includes the following:

• Hormone therapies, which slow or stop hormone-sensitive tumors from growing. These types of tumors require certain hormones to survive and replicate and are most commonly used to treat patients with breast and prostate cancer.
• Signal transduction inhibitors, which block signals that cancer cells use as part of their replication process. In simple terms, cancer cells don’t have an “off switch” to stop dividing and growing. Signal transduction inhibitors use chemicals to affect how these cancer cells receive information from their environment and ultimately block the signals the cells rely on for replication.
• Apoptosis inducers also work to stop cancer cells from reproducing. These targeted therapies “confuse” cancer cells so that they die in a controlled fashion.
• Anti-angiogenesis drugs block the growth of blood vessels, which are required for tumors to get the blood and nutrients they need to survive. When anti-angiogenesis drugs work, they starve tumors of the blood supply that would otherwise allow the cancer cells to keep growing.
• Immunotherapies work by stimulating a patient’s immune system to attack cancer cells. Much like a vaccine, some immunotherapies rely on the patient’s own disease-fighting defenses by “tagging” cancer cells with molecules that make the cancer cells targets for the immune system. Still, other immunotherapies work by helping the patient’s immune cells more effectively kill cancer cells.
• Monoclonal antibodies are used in immunotherapies, and they’re also used to deliver toxic molecules to cancer cells. The monoclonal antibody attaches to a cancer cell along with another molecule that destroys the cancer cell. Think of it as a bomb attached to a missile. The monoclonal antibody is the missile, and the other molecule is the bomb. And with this type of targeted therapy, only the cancer cells are destroyed.

In addition to these targeted therapies for treating cancer, we also use advanced science to better identify which people may be at higher risk for developing cancer. Through genetic testing, we can determine who carries certain gene mutations that make them more susceptible to developing specific cancers. For example, we know that women and men who have the BRCA1 or BRCA2 gene mutation are much more likely to develop breast cancer, ovarian cancer, or prostate cancer (in men). This type of genetic testing is known as “germline” testing.

We also use genetics to better understand which patients may benefit from certain treatments. This type of testing is called genomic testing, and it examines the genetic makeup of a patient’s tumor to determine how the tumor is different – or mutated – from normal cells. Knowing which mutations are responsible for a patient’s cancer can help us better design treatments and even monitor the presence of disease after treatment by creating tests that measure tumor DNA circulating in a patient’s blood.