Word: celling
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Dates: during 1990-1999
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Cancer, scientists now realize, is a genetic disease. It is caused by multiple mutations in the genes that control cell division, the process through which a cell makes a copy of itself by splitting in two. Some of these genes, known as oncogenes, stimulate cell division, while still others, called tumor-suppressor genes, damp it down. In their normal form, both types of genes work together, enabling the body to replace dead cells and repair damaged ones. But mutations in these genes--whether inherited or acquired through environmental insult--very quickly cause a cell to careen out of control, like...
...essence, cancer is an evolutionary drama played out in one part of the body or another--the lung, the breast, the brain. Over time, a single abnormal cell becomes two, then four, then eight, then 16. Early on, these cells develop a repertoire of "tricks" that confer a survival advantage. Among other things, the tricks ensure that mutation will pile on mutation by shucking off, or silencing, genes that ordinarily monitor replicating DNA for chemical errors. The malignant cells quickly become resistant to the poisons physicians prescribe to kill them. They also acquire the disturbing ability to stimulate the formation...
STOPPING THE CELL CYCLE When a cell divides, normally or otherwise, it does so not all at once but in a series of carefully orchestrated steps. Each step provides oncologists with an opportunity to intervene in the process. In order to complete a successful division, for example, a cell must first faithfully copy its DNA. If a cell makes mistakes in this critical task, vigilant enzymes quickly call a halt to the process until repairs can be made. Sometimes, however, the DNA of a dividing cell is too badly damaged to be salvaged. At this point, these same enzymes help...
Virtually all anticancer drugs interfere with cell division in some fashion. Cyclophosphamide, the compound that finally banished Dustin Fagan's cancer, belongs to a broad class of drugs that damage the DNA molecule by plastering it with sticky cross-links, thus triggering the suicide sequence. By contrast, the taxoids--including taxol, the compound isolated from the bark of the yew tree that was approved by the Food and Drug Administration as a weapon against ovarian cancer in 1992--cause the same suicidal result by deactivating a molecular machine that, just before cell division, separates the DNA in each chromosome into...
...source of the new hope is the experience of Patricia Haut, a former real estate broker from Auburn, Michigan. Eleven years ago, Haut, then 44, was found to have a slowly progressing but often fatal form of B-cell lymphoma, a disease that afflicts the very white blood cells that make antibodies in the first place. Like most patients, she initially responded to chemotherapy. But after each treatment, the cancer recurred. Then three years ago, as her remissions grew ominously shorter, Haut enrolled in an experimental trial of monoclonal-antibody therapy at Michigan. Over the course of five weeks...