Are Breast Cancer Vaccines The New Chemotherapy?

The idea of curing breast cancer with a simple therapeutic vaccine instead of surgery and/or months of chemotherapy or radiation is very appealing to patients and breast cancer centers alike. And while we're not quite there yet scientifically, that certainly is the goal—one that's within reach.

In the past year, medical powerhouses like the Mayo Clinic, Johns Hopkins and MD Anderson have been studying various therapeutic breast cancer vaccines, all showing promise.

The Mayo Clinic is currently working on a breast cancer vaccine for a highly aggressive type called 'triple negative', which affects 15-20% of breast cancer patients. It cannot be treated by estrogen blockers like Tamoxifen, as this particular form of breast cancer is not fueled by estrogen. Instead, chemotherapy for this breast cancer type is currently the only treatment option, and that even with chemotherapy, the breast cancer is likely to return and metastasize.

Johns Hopkins is studying experimental breast cancer vaccine in clinical trials as well. This breast cancer vaccine awakens the immune system and teaches lead immune cells to attack breast cancer cells, something the cells do not inherently detect as foreign or dangerous.

The MD Anderson Cancer Center is studying ways to boost the body's immune system to fight metastatic breast cancer, and to prevent recurrence. Researchers there have taken on hard-to-treat metastatic cancer because of its aggressive nature.

In nearly every cancer center where research is happening (and well funded), breast cancer vaccines are being developed and studied and with good reason. Even with the improved cure rate using current therapies like chemotherapy for breast cancer, experts estimate that more than 200,000 women in the United States will be diagnosed with breast cancer each year.

The collective mission among breast cancer centers, researchers, patients, survivors and the society as a whole is to wipe out breast cancer entirely. To do that, a second kind of breast cancer vaccine is needed: the preventative vaccine.

Currently, the Cleveland Clinic is studying a breast cancer vaccine that the researchers believe will prevent cancer from occurring in the first place. They have already demonstrated success in mice. The study is now in Phase 1 of FDA clinical trials on its effectiveness on humans. This particular breast cancer vaccine is designed to activate the immune system to attack a type of protein only found in breast cancer tumors.

Experts predict that a successful vaccine will be approved and ready for use in a handful of years, not decades. So while chemotherapy for breast cancer is hardly a therapy of the past, breast cancer vaccine research seems to be paving the way for a world without breast cancer chemotherapy, radiation and most importantly, breast cancer itself.

SNCC Offers Immunotherapy, Cancer Vaccines

The immune system is developed to help protect the body from infections and diseases. Immune cells are designed to travel through the body to detect harmful germs or cells that can cause infections. The immune system can also help protect the body from cancer in some ways; however, there are limits to what the immune system can do to fight cancer on its own.

When dealing with cancer, there are many treatment options available. Determining the best and most effective treatment for your cancer case can seem overwhelming, which is why you need a cancer expert on your side to answer questions. And one set of questions you may have may be about immunotherapy, which can include cancer vaccines.

“Immunotherapy is a constantly evolving treatment option for cancer,” said Dr. Jorge Perez with Sierra Nevada Cancer Center. “Its focus is on enhancing the immune system, enacting the body’s own defenses to fight off, or stop, the spread of cancer in the body.”

Immunotherapy can help treat a variety of cancers such as melanoma, breast, prostate and lung cancer.

Melanoma is the deadliest form of skin cancer and is responsible for the majority of skin cancer-related deaths. Breast cancer is the most common cancer diagnosed in women, whereas prostate cancer is the most common cancer among men and lung cancer is a leading cause of cancer deaths. The most common treatment options for these types of cancer may consist of surgery followed by radiation therapy, chemotherapy and targeted therapy.

But for many different types of cancer, immunotherapy has shown to be effective in a variety of clinical outcomes for patients with cancer. Immunotherapy can be used in conjunction with other cancer treatment options such as radiation or chemotherapy.

The most effective immunotherapy treatments for cancer consist of:

• cancer vaccines, which help trigger the immune system to attack tumor antigens;
• monoclonal antibodies (mAbs), where generated molecules or antibodies target cancer tumors by causing an immune response;
• Checkpoint inhibitors, which are target molecules that produce or enhance pre-existing anti-cancer immune responses to attack cancer cells.

Cancer Vaccines

There are two different types of cancer vaccines: vaccines that can prevent certain types of cancer and vaccines that can help treat cancer.

Similar to traditional vaccines used to prevent the chickenpox or the flu, cancer vaccines can help prevent or treat cancer. Preventive cancer vaccines are most effective for cancers known to be caused by infections, like the HPV vaccine, which helps prevent cervical, anal or throat cancers that can begin as an infection. Most cancers such as lung, prostate and breast cancers are not thought to be caused by infections and therefore can not be prevented by a cancer vaccine.

However, treatment cancer vaccines help boost the immune system to attack against cancer cells in the body. Take, for example, Sipuleucel-T (Provenge®), the only U.S. Food and Drug Administration (FDA) approved vaccine used to treat advanced prostate cancer that is no longer being helped by hormone therapy. Although the vaccine cannot cure prostate cancer, it has helped extend the lives of men with prostate cancer.

Monoclonal Antibodies

Monoclonal antibodies (mAbs) are man-made antibodies that specifically target a certain antigen, such as one that is found in cancer cells. When dealing with cancer, creating monoclonal antibodies can be difficult, especially when trying to identify the right antigen to attack. The FDA has approved more than a dozen mAbs to treat certain cancers. There are two main types of mAbs: naked mAbs, which are antibodies not attached to drugs or radioactive material, and conjugated mAbs, which are joined to a chemotherapy drug or a radioactive particle. Adoptive T cell therapy can be similar to mAbs, but instead, T cells are removed from a patient and then modified or treated to enhance activity. They are then transferred back into the patient to improve the immune system’s anti-cancer response.

Checkpoint Inhibitors

Checkpoints in the immune system are important to keep the immune system from attacking the normal cells in the body, but oftentimes cancer cells can find ways to avoid these checkpoints and avoid being attacked by the immune system. Checkpoint inhibitors can access these immune cells that need to be activated to start an immune response to recognize and attack cancer cells in the body. These inhibitors are particularly effective in treating advanced melanoma by blocking the protein that typically prevent the immune system from attacking itself, often shrinking tumors and helping patients live longer.

Although they cannot cure or prevent cancer, these immunotherapy treatments have helped certain patients with their specific cancer case. As researchers begin to understand and learn about the immune system and how it can be used to treat cancer, immunotherapy treatments are constantly changing and advancing. Some immunotherapy treatments focus on simply boosting the body’s immune system, whereas others are used to train the immune system to specifically attack cancer cells.