Scattered throughout the body’s tissues are hordes of exquisite cellular machines called Adult Stem Cells (ACS). Each of these marvelous little cells is endowed with the power to perform astonishing works of biological magic.
When your skin is broken, adult skin stem cells at the affected site swing into action. They divide, and morph along the way. Some become sheets of cells, the precursor of new layers of skin. Others form sinuous filaments that wind through and in between the sheets, soon to conduct nutrients and oxygen; these will serve as capillaries. A similar process repairs other organs and tissues, liver, stomach, bone, etc. The process is regulated by untold thousands of biochemical handshakes between each microscopic player, as they grow from individual ASC to tissue containing many different kinds of cells. It’s an amazing phenomenon, and one made all the more fascinating as it happens without any conscious thought or direction. But sometimes, it can take a sinister turn ...
If, in the journey from ASC to new tissues, a few key genes are garbled, the cell may never stop dividing. Worse still, the body’s defenses are fooled by the errant cell’s outward appearance and chemical signature. Nearby quickening cells still dutifully build blood vessels and supporting tissue to nourish the growing collection. The owner will be unaware of the tiny malfunction, until they notice a lump, or until it affects the proper operation of an organ. At which point they consult a doctor, learn the chilling diagnosis, and the battle againt cancer begins.
For some time, researchers have suspected that Adult Stem Calls might play a role on the early development of the disease. More recently, there is some evidence that not only can the malignancy be triggered by an ACS, the cancer itself can arise from a mutated stem cell, a cancer stem cell, which produces only cancerous tissue. Needless to say, even if most of the tumor is removed or shrunk, just one cancer stem cell can give rise to a new tumor. And if those cancerous stem cells drift away from the original tumor, the new cancer appears in whatever tissue the malignant cells settle:
Three years ago, Weissman discovered that mutations and rearrangements of the genomes of stem cells that give rise to all the cells of the blood can lead to some forms of leukemia. Weissman proposed that these changes could underlie the development of cancers in many tissues.
Over one-million Americans will be diagnosed with some form of cancer every year. In some cases, the struggle they will endure, the courage they will summon, is simply unimaginable. If you’ve witnessed or experienced the devastating emotional and physical roller-coaster that makes up a cancer patient’s life, you understand all too well. If not, I hope you never do.
Cancer is second only to cardiovascular disease as the leading cause of death in the US. And yet, the outlook for survivors like Elizabeth Edwards has never been brighter. New treatments are being developed and refined, and insight into the role of adult stem cells, viral infections, and other possible causes holds great promise for future generations. The disease is slowly, ever so slowly, becoming less a death sentence and more a chronic illness which can be managed, especially when caught early. Here’s to hoping that one day, in the near future, with enough funding, research, government leadership, and perhaps most importantly, affordable access to quality healthcare, all the victims of this disease can look forward to a long, healthy, and full life.