A US team of scientists have developed a new vaccine which eliminates a type of breast cancer.
The research focussed on breast cancer caused by excessive levels of the protein HER2 . HER2 receptors promote normal cell growth, but in cases of HER2-positive, the breast cells have many more receptors which promote an aggressive cancerous tumour. This type of breast cancer affects around 30% of all breast cancer patients.
The experiments used electrical pulses to inject the new vaccine into the leg muscles of mice. Once injected, the vaccine increased HER2 receptors which stimulated an immune system reaction, enabling them to fight the cancer. Scientists used a drug to suppress T cell activity (regulatory cells that normally trigger the immune system’s response). Without the interference of the T cells, the immune system was able to react more effectively to the vaccine. Researchers found that once the HER2 had been injected, the cancer was destroyed and no side-effects were apparent.
Lead researcher Professor Wei-Zen Wei said: “The immune response against HER2-positive receptors we saw in this study is powerful. Both tumour cells that respond to current targeted therapies and those that are resistant to these treatments were eradicated. This may be an answer for women with these tumours who become resistant to the current therapies.”
There are a number of drug therapies available to treat this form of breast cancer, including Herceptin. However, they are ineffective for the many patients. The same group of researchers previously developed a vaccine based on similar principles, and which is currently in early clinical trials. This new wave of drug development though is believed to be a more effective treatment, containing genes that produce the HER2 receptor.
Dr Sarah Rawlings, of the charity Breakthrough Breast Cancer, commented that although the news is very positive, it is still “very early research that has only been carried out in mice so we don’t actually know if it could be used in women.” She added: “Much more research is needed to find out if it works, to either treat HER2 positive breast cancer or prevent the disease, and if there are any side effects.”
The US based scientists found that the vaccine could destroy tumours resistant to current drug treatments, and believe the vaccine may even be used to prevent initial development of the tumours in cancer-free women.
The study is by Wayne State University and is published in the journal Cancer Research.
