Learning More About Lung Cancer in the Lab

Christine Wilson, cancer survivor, shares her experiences from the Abramson Cancer Center’s 2012- Focus on Lung Cancer Conference. In this blog, she discusses how basic science research can bring about new treatments for lung cancer.

"The answer lies in our DNA--the blueprint for life." Steven Abeida, MD

Basic science research is complex, but very important because it teaches researchers about how cancer cells grow and respond to treatment.

One way findings from basic science is translating into treatments for lung cancer is through personalized medicine. By studying the way cells act and interact within the body, researchers can explore more personalized approaches to lung cancer treatment.

Cancer occurs when cells grow and divide in an uncontrolled way. That sounds like a relatively simple statement, but the processes that control normal, and abnormal cell growth, turn out to be very complex. In fact, the more researchers learn about how cells behave, the more complex it becomes.

For lung cancer patients, there are several core concepts that can help you understand how unraveling the mysteries of DNA is leading to the new era of personalized medicine.

• Normal cell growth is carefully controlled. Cells only grow and divide when they get a specific signal to do so. Think about wound healing as an example.
• Normal cells are programmed to live for a period of time and then die. Cancer cells are often "immortal," meaning they don't "listen to or receive " the signal to die.
• Cell growth is controlled by genes that turn on and off as needed. Cancer occurs when these genes are damaged and the signaling is disrupted. It is as if you are driving a car and either the accelerator gets stuck in the go position, or the brakes fail.
• These genes don't work by themselves or in isolation. They are all part of pathways--sequences of inter-related reactions that regulate cell growth.
• Researchers have identified a number of "driver mutations” - specific genetic changes that are essential to the growth and survival of the cancer cells. These are the targets of new therapeutic approaches.
• Cancer cells are "smart." They continue to change and evolve, developing new ways of growing and resisting attacks from either standard treatments or newer targeted ones.

What does this mean for lung cancer patients?

Right now, doctors are able to identify several driver mutations in lung cancer and target those with therapies that block the pathways.

• EGFR is a mutation found in about 10% of patients with adenocarcinoma of the lung. It can be targeted with the drug erlotinib.
• ALK-1 is found in about 5% of lung cancer patients. The drug crizotonib is showing real promise in treating people with this mutation.

That' s only 15% of people who have lung cancer though. The goal now is to find more driver mutations, and to develop drugs that target known mutations. KRAS, for example, is found in a higher percentage of lung cancer patients, but there is currently no drug available that targets this mutation.

The real goal for the future is to be able to identify driver mutations in every tumor, and treat that tumor on an individual basis. That means full gene sequencing for every patient.

One obstacle to achieving that goal is the need for tissue, which come only from biopsies. Circulating tumor cells could prove to be another significant advance. This technology allows doctors to find tiny numbers of cancer cells in the blood; cells that can be used to profile tumors, monitor response to treatment and determine the best therapeutic approaches for every patient.