Repurposing Older Drugs For Cancer Treatment
We have long known that the body puts out special hormones or chemicals in response to stress and inflammation. The most important of these are epinephrine (Adrenaline™), cortisone, and hormones called prostaglandins. Most of you are familiar with epinephrine and cortisone but possibly not so much with prostaglandins. Prostaglandins are hormones that are created with a chemical reaction that occurs at the site of an injury. Prostaglandins are unlike epinephrine and cortisone which are secreted from a gland, the adrenal gland. When tissue is damaged or infected, prostaglandins create reactions that cause pain and fever and inflammation, and this sparks the healing process. In women, these hormones can start labor and control ovulation. The problem with prostaglandins is that they can produce unwanted inflammation in the body. Although they are a natural response to stress, excess production can cause chronic pain. Some of the anti-inflammatory medications such as ibuprofen and naproxen work by blocking the enzymes that cause these hormones to be produced, and thereby reducing inflammation and pain. Prostaglandins along with epinephrine and cortisone are secreted what is called the stress – inflammatory process.
Cortisone on the other hand is a synthetic chemical that mimics the action of a hormone called cortisol. Furthermore, cortisol belongs to a larger group of hormones called glucocorticoids. Cortisol is a hormone that reduces inflammation and is often used to inject joints in people who have arthritis and other inflammatory changes. Epinephrine belongs to a group of hormones called catecholamines. Epinephrine is one of our primary stress hormones. When we become afraid, our heartbeat goes up and we may begin to perspire. The secretion of epinephrine is the cause of this type of stress reaction.
Epinephrine, cortisone, and drugs that block prostaglandins have been on the market for decades. But what scientists have now found is that the stress – inflammatory response may trigger spread of cancer, metastases. One of most intense stress- inflammatory responses occurs before, during and after a large surgical procedure. If we could block this stress – inflammatory response, we might be able to improve the cancer cure rate. In recent work on patients with both colorectal and breast cancer, this is precisely what has been done.
In several small studies looking at colorectal and breast cancer, researchers gave patients both propranolol (a drug which blocks epinephrine) and etodolac (Lodine™), a drug that blocks prostaglandins. They administered the drugs for several days before surgery, the day of surgery, and several days after surgery. A second group of patients received a placebo instead of the study medication. In prior studies it was noted that blocking or administering cortisone was of no value so it was given to patients in these current up-to-date studies. Currently, we do not have long-term follow-up on any of these patients. However, the results that are seen strongly favor the group that received the medication when compared to those receiving a placebo.
It therefore appears from the studies that obliterating the inflammatory – stress response to surgery may potentially impact long-term survival.