Immune-Based Therapy May Hold Key to Breast Cancer

By Erika Celeste
Baltimore, Maryland
12 November 2009

(VOA) - Breast cancer is the second leading cause of cancer deaths worldwide, behind lung cancer, and it is the most common cancer among women. Once it begins to spread through the body, it's considered incurable.  But new research into an immune-based therapy by Dr. Leisha Emens at Johns Hopkins Hospital in Baltimore, Maryland may hold the key to treating it.

A completely different approach

"The neat thing about immune-based therapy for cancer treatment is that it works completely differently than anything that's out there," Emens said. Emens, an oncologist, became interested in studying breast cancer when she was 16, after her mother died of the disease.

Dr. Leisha Emens works to elucidate mechanisms of immunoregulation in patients with breast cancer using the vaccine in combination with standard breast cancer drugs and novel therapeutics

"Ever since then I've always been interested in, why? What makes normal cells turn into cancer cells and [I was] thinking that if we could understand that, we would better be able to treat it," she said.

Cancer, Emens explained, is not just one disease, but a whole range of diseases, each of which needs different treatments. "So it's pretty tough to develop 'the cure' because there's probably not going to be just the cure for cancer, there's going to be a lot of different ways to approach it, depending on the type of tumor that it is, and the subtype of tumor within that type," she said.

Cancer cells sneak past the body's defenses

Because cancers result when the body's own cells reproduce uncontrollably, the immune system has a tendency to see them as 'safe' and therefore doesn't try to fight them off. But Emens is working on a vaccine that would re-educate the immune system to recognize subtle changes in tumor cells as dangerous, which would alert the system to seek out and destroy the harmful cells.

To make the breast cancer vaccine, Emens took two major types of breast cancer cells and modified them to secrete a special hormone that stimulates the immune system. She explained that it's specifically programmed to initiate an immune response. "It acts like a danger signal to wake the immune system up. It also attracts a particular type of cell in your body that acts like the orchestra leader for the immune response," she said.

Darby Steadman participated in Emens' first vaccine trial and appreciates Emens' perspective on cancer

Darby Steadman, the mother of two young children who has terminal breast cancer that has spread to her spine, participated in Emens' first vaccine trial.

Steadman appreciated Emens' perspective on cancer. "She was looking at my diagnosis as a chronic disease as opposed to a death warrant. It was such a wonderful way of looking at it, like, 'Oh, I can live with cancer, I'm not dying of cancer, I'm going to live with cancer.' So it was a shocking way of looking at it, as compared to some of the other [doctors] I had been talking to," Steadman said.

A treatment, not a cure

Emens' vaccine is for patients with breast cancer that has spread into areas such as bones, liver or lungs. And it's designed to treat the disease, not prevent it. Still, Steadman welcomed the chance to help test its effectiveness. "This actually can turn something that is so terrible, like metastatic breast cancer, into an opportunity to do something for my children or my siblings or my nieces."
 
Emen's approach might be useful in treating a variety of breast cancers that share a characteristic that allows the vaccine to slip into tumor cells. "We're not directly attacking the tumor and trying to kill tumor cells with the therapy," Emens stressed. " We're actually teaching your body to deal with the tumor itself. So we're actually engaging your own body to fight against the cancer. And the thing about the immune system is that it can remember, so you have this memory response. So that enables us to move this type of therapy earlier and earlier in disease treatment and hopefully prevent people from relapsing," she said.

Climbing mountains for research funding

Developing new drugs is expensive, and Emens must apply for grants and raise money in other ways to continue her research. Most of her funding comes from leading mountain climbing expeditions. She's scaled numerous peaks including Mount Kilimanjaro in Tanzania and Mount Cotopaxi in Ecuador. When asked to elaborate on her adventures on behalf of research, she dismisses the interest, saying she just loves nature and anyone in her place would do the same thing.

But Darby Steadman disagrees. "She's a one-woman show. To me, that's wonderful. She's very proactive when it comes to trying to make sure she has the funding she needs to do this trial."

Steadman has just had her one year check-up. While she will most likely have cancer for the rest of her life, she is healthy for now. She believes Leisha Emens is in part responsible for that. Therefore, she and her friends have started a foundation to help raise money for Emens' research.

"The most important thing for people to know is that there is a human side to trials. It's not some sort of nebulous thing that's in some research paper that some sort of doctor comes up with. There are human patients with stories, and it's amazing to me how one woman has now given us hope that there could be a cure, and maybe this vaccine did do something for me, and look, it may do something for my children and my grandchildren. I think that's a beautiful story," Steadman said.  

Leisha Emens' work is far from complete. Typically, it takes a new drug about 20 years to be researched before the U.S. Food and Drug Administration will approve it for widespread use. She still has at least ten years to go before her vaccine therapy may be approved. And ultimately, she hopes that her research leads to the development of a vaccine that will prevent breast cancer altogether.