Recent discoveries that shed light on how tumors grow are giving doctors new tools to fight cancer. It's just the beginning, and there's a long way to go, but the future of cancer treatment is hopeful.
The Role of Genes in Cancer
The Human Genome Project mapped all of the genes in the human body. This huge project gave scientists a blueprint of our genes and how they control the body. It’s had a big impact on our understanding of cancer.
The roots of cancer lie in genes. Cancer begins when a gene changes, or "mutates." This allows cells to grow out of control.
Scientists knew that genes play a role in cancer. But mapping the sequence of DNA helped them see what was normal and what wasn't. Now they can pinpoint problems with genes that are linked to cancer and see how cells interact to spark tumor growth.
These new insights help doctors create new cancer treatments. They can prescribe drugs that zero in on certain parts of cells -- like genes, proteins, or blood vessels -- that trigger the growth of tumors.
These treatments are different from standard cancer treatments like chemotherapy because they focus on specific targets. Chemotherapy kills quickly dividing cells all over the body, including hair cells and immune cells.
EGFR inhibitors are one type of targeted therapy. Some people with lung cancer have a mutation in the EGFR gene, which helps cancer cells grow. Drugs that block this gene may slow or stop cancer growth.
Another type of targeted therapy is called an angiogenesis inhibitor. It blocks the growth of new blood vessels that tumors need to survive.
Targeted therapy is used to treat several types of cancer, including breast, colorectal, head and neck, liver, lung, leukemia, lymphoma, kidney, stomach, and melanoma. Researchers are studying other possible cancer targets.
Cancer and the Immune System
Scientists have pulled back the curtain on how the immune system, your body's defense against germs, responds to cancer. That research has opened the way for new drugs that give your immune system the power to attack cancer. It's an approach called immunotherapy.
Your immune system often has trouble targeting cancer cells. Sometimes its response is too weak to help. Other times it doesn't recognize the cells. And some cancer cells trick immune cells into ignoring them.
Immunotherapy tackles these problems in different ways.
Some treatments, like interferon and interleukin, rev up your immune system response against the cancer. Others, like cancer vaccines, train your immune cells to hunt down the cancer.
Another type of immunotherapy works on checkpoints. Think of them as beacons attached to your body's normal cells. They help your immune system identify your own cells so it won't go after them. Cancer cells can hide behind these checkpoints. Inhibitors turn off the checkpoints on cancer cells to help your immune system find them.
Immunotherapy doesn't work for everyone or for all types of cancer. These drugs have been successful in treating several cancers including bladder, colorectal, head and neck, kidney, leukemia, lymphoma, melanoma, and stomach.
Doctors now have several immunotherapy drugs to choose from, and more treatments are in studies.
There's still plenty of work to be done in cancer research. Figuring out who will benefit from targeted treatment and immunotherapy is an important next step. And more types of tumors -- and treatments for them -- need in-depth study.
Researchers still need to make more progress in understanding individual differences. People with cancer don't all respond to treatments in the same way.
The next frontier is to tailor treatments for different people. Targeting treatments to the unique genetic makeup of each cancer will help improve the odds that the drugs will work. A personalized approach could bring new breakthroughs in cancer treatment in the years ahead.