Comprehensive Nursing Pharmacology Q 33
Hormonal agents are used to treat some cancers. An example would be:
A. Thyroxine to treat thyroid cancer.
B. ACTH to treat adrenal carcinoma.
C. Estrogen antagonists to treat breast cancer.
D. Glucagon to treat pancreatic carcinoma.
Correct Answer: C. Estrogen antagonists to treat breast cancer.
Estrogen antagonists are used to treat estrogen hormone-dependent cancer, such as breast carcinoma. A well-known estrogen antagonist used in breast cancer therapy is tamoxifen (Nolvadex). This drug, in combination with surgery and other chemotherapeutic drugs, reduces breast cancer recurrence by 30 percent. Estrogen antagonists can also be administered to prevent breast cancer in women who have a strong family history of the disease.
Option A: Thyroxine is a natural thyroid hormone. It does not treat thyroid cancer. Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It is the inactive form and most of it is converted to an active form called triiodothyronine by organs such as the liver and kidneys. Thyroid hormones play vital roles in regulating the body’s metabolic rate, heart, and digestive functions, muscle control, brain development, and maintenance of bones.
Option B: ACTH is an anterior pituitary hormone, which stimulates the adrenal glands to release glucocorticoids. It does not treat adrenal cancer. Adrenocorticotropic hormone (ACTH) is a tropic hormone produced by the anterior pituitary. The hypothalamic-pituitary axis controls it. ACTH regulates cortisol and androgen production. ACTH receptors are in the adrenal cortex, in particular, the zona fasciculata and zona reticularis. The receptors are G protein-coupled receptors thus stimulating adenylyl cyclase. This leads to an increase in intracellular cAMP and activation of protein kinase A.
Option D: Glucagon is a pancreatic alpha cell hormone, which stimulates glycogenolysis and gluconeogenesis. It does not treat pancreatic cancer. Glucagon is a polypeptide hormone commonly used in the treatment of severe hypoglycemia with FDA approval for the treatment of severe hypoglycemia and as a diagnostic aid in imaging of the GI tract. Glucagon binds G-coupled surface receptors found throughout the body in varying concentrations; binding to the glucagon receptors in the liver, GI tract, heart, pancreas, fat, adrenal glands, and kidneys activate adenylate cyclase which in turn raises cAMP levels. cAMP stimulates glycogenolysis and gluconeogenesis, resulting in the release of glucose, primarily from liver glycogen stores. The extrahepatic effects of glucagon are also mediated by adenylate cyclase, including relaxation of GI smooth muscle and positive inotropic effects.