Fighting Cancer with Infection

Salmonella may help treat stomach, liver, spleen, and colon cancer

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) University of Minnesota researchers have discovered an unlikely way to help cancer patients using salmonella - a bacteria that causes thousands of food borne illnesses in the United States each year.

Essentially, the researchers are trying to 'weaponize' salmonella in order to treat cancers around the gut, such as stomach, liver, spleen, and colon cancer. Because salmonella naturally infects the body in these areas, a genetically modified form of salmonella may be able to attack cancer cells in the environment in which the bacteria thrives.

In trials on animals, researchers have already shown that salmonella can control tumors of the gut. Trials on humans are currently underway, with reports showing promise.

dailyRx Insight:  Salmonella may be able to kill stomach cancer.

According to lead researcher Edward Greeno, M.D., Medical Director of the Masonic Cancer Clinic, bacteria and viruses have been shown to work against disease. Consequently, Greeno and his colleagues believe that bacterial infection may also be useful in fighting cancer. In fact, Greeno cites an Austrian report from the 1860s that tells of a tumor patient who was placed in the same room as another patient who had a bad infection. Once the tumor became infected, it all but disappeared. However, the study comes to an unfortunate end: the patient ended up dying from the infection instead of the tumor.

In light of this centuries-old report, Greeno and colleagues' goal for this researcher endeavor was to figure out how to get salmonella to infect and fight a tumor, without making the patient ill.

First, Dan Saltzman, M.D., Ph.D., created a genetically modified and weakened version of salmonella. Interlueken 2 (IL-2) was also added to the modified salmonella. Saltzman describes IL-2 as a 'guard dog' that sniffs around looking for threats to the body. To continue the metaphor, the dog then barks (signals an immune system response) when it finds a threat.

Salmonella naturally finds its way not only to a person's gut and related tissues, but also to a tumor. As such, a convenient way to get IL-2 to a cancer of the bowels is by attaching it to salmonella.

Basically, Greeno and Saltzman created a two-pronged approach to attacking cancer: a combination of the immune response triggered by IL-2 and the infection caused by salmonella.

According to Greeno, it is unlikely that such this new treatment will replace chemotherapy and radiation treatments, but it can still serve as one of many tools in the fight against cancer. Furthermore, the salmonella treatment could potentially be cheaper and less toxic than current treatments.

Cancer is diagnosed in over 12 million people each year, and kills over 7 million. It is the largest cause of death in the developing world, and one out of ever three people will be diagnosed with an invasive cancer at some point in their lifetime. Cancer is a group of diseases classified by abnormal and uncontrolled cellular growth in a particular organ or tissue type in the body. When the growth invades other tissues, causes damage to them, or spreads to different parts of the body it is considered malignant. Cancer is caused by a multitude of factors including genetics and infections, but a majority of cancers can be attributed to environmental causes, such as smoking, and being exposed to carcinogens or radiation. Symptoms of cancer are variable. In some cases, the cancer will produce symptoms that affect the organ it is located in, such as coughing and shortness of breath from a lung cancer, constipation and bloody stools from colon cancer, or headaches and cognitive problems from a brain cancer. Other cancers such as leukemia and blood cancers may produce flu-like symptoms and sudden infections. Some cancers may be discovered by a lump, or physical evidence, such as in breast cancer. Treatment for cancer is usually one of or a combination of surgery to remove it, radiation therapy, and chemotherapy. Newer treatments such as hormonal drugs and targeted drugs are making cancer treatment even more specific to the patient and the disease. Diagnosis is based off of physical examination and several imaging techniques such as MRI, PET scan, and laparoscopy. Definitive diagnosis is achieved when a piece of cancerous tissue is examined by a pathologist.

Funding for this study came from the National Institutes of Health, the Masonic Cancer Center, and Botanic Oil Innovations.

Reviewed by: 
Review Date: 
March 9, 2011
Last Updated:
March 11, 2011