Oncogenes and the Hallmarks of Cancer
Q: Which of the following best describes a 'gain-of-function' mutation in an oncogene?
Did You Know?
True. Syndrome of Inappropriate Antidiuretic Hormone (SIADH) is characterized by the persistent, non-physiological release of Antidiuretic Hormone (ADH, or vasopressin) despite normal or low plasma osmolality. This leads to excessive water reabsorption in the kidneys' collecting ducts. The retained water dilutes the sodium in the blood, causing hyponatremia (low serum sodium) and a state of volume expansion (but without edema, because the water is evenly distributed). Common causes include certain cancers (e.g., small cell lung cancer producing ectopic ADH), central nervous system disorders (stroke, infection), pulmonary diseases, and some medications. Symptoms are primarily neurological due to cerebral edema and range from headache, nausea, and confusion to seizures, coma, and death in severe cases. Treatment involves fluid restriction, addressing the underlying cause, and sometimes hypertonic saline or medications like demeclocycline.
Social Sharing!
Share your knowledge:
Zambia