Lumps, bumps, and unusual marks have long heralded cancer, from a bulging jaw in an australopithecine fossil, to traces of melanoma in a 2,400-year-old Incan mummy, to the frightening discovery of a dimpled breast today. Since the 1970s, a portrait of carcinogenesis has emerged from a series of genetic insults that pushed cells to proliferate, invade, and spread. Today, gene expression profiling is expanding that view to embrace a waxing and waning of protein levels that provide a dynamic bac

Cancer is the price we pay for our multicellularity. The initial sculpting of tissues and organs in the embryo, their elaboration in childhood and maintenance for decades thereafter, requires trillions of cell divisions. With a task of that magnitude it is perhaps inevitable that some of those divisions will be mistimed or misplaced. The result of such an error, if left unchecked, is an out-of-control growth: cancer. It is a wonder that cancer doesn't affect more of us--but one in three is sti

Attenuating or preventing cancer begins with understanding how the deviation starts. While molecular biologists uncover the errant signals that subvert cells, epidemiologists close in on environmental triggers--which are, for now, easier to target. Cancer prevention strategies against long-known culprits are pervasive, yet mostly passive, such as admonitions to avoid smoking, sunning, and obesity. Efforts, however, span several levels, from the World Health Organization's Framework Convention

The Y chromosome has long had an image problem. A male grasshopper lacks a Y, and a male bee stems from an egg that the queen deemed unfertilizable. Turtle eggs laid in the sun become sisters, their shaded brethren, brothers. And although most mammalian males do indeed have Ys, the two species that don't--mole voles--are apparently fine. They even copulate. But the Y's lowly status has changed; now, it seems, the Y has been evolving, not dying, thanks to work by David Page and others at the

Courtesy of Eric D. Laywell SPHERES OF PROMISE These neurospheres, clusters of cells in culture derived from the CNS of mice, are stained with antibodies against a neuronal protein (red), and a astrocyte protein (green). They have a nuclear counterstain (blue). The brain and spinal cord were once considered mitotic dead ends, a division of neurons dwindling with toddlerhood, with memory and learning the consequence of synaptic plasticity, not new neurons. But the discovery of neural stem

5-Prime | Stem Cell Fusion Confusion 1. How did the idea of transdifferentiation arise? In the late 1990s, sex-mismatched transplants and experiments with rodents revealed apparent transgressions of embryonic cell fates. Bone marrow cells could yield liver, muscle, neuron, and endothelium, while neurons could give rise to blood, and hepatocytes to pancreatic beta cells. Stem cells seemed to home in on injury sites, producing daughters that dedifferentiate and redifferentiate into exactly

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Asking students to taste PTC-soaked paper is a classic classroom exercise to demonstrate a simple inherited trait. Some grimace, others look puzzled. "PTC perception is arguably one of the most studied human traits," says Sun-Wei Guo, a professor of pediatrics and biostatistics at the Medical College of Wisconsin in Milwaukee. A new investigation reveals more to chew on: Rare individuals who are not quite sure whether they taste phenylthiocarbamide (PTC) have provided a hint that the inherit

Courtesy: Larry Marsh and Judit Pallos  IN A FLY'S EYE: The regular repeating structure of the Drosophila melanogaster compound eye is disrupted when polyglutamine (polyQ 108) is expressed, making the fly eye an excellent model for huntingtin-derived pathology. Dissecting the mechanism of neuronal demise in Huntington disease (HD) has had its share of twists and turns. It took a decade to go from marker1 to gene,2 and now, after another decade, the details are beginning to come together.

Development of pox-like lesions suggests vaccination doesn't protect against altered viruses.

Courtesy of Upstate Cell Signaling Solutions  CONNECT THE DOTS: Apoptosis is a highly complex cellular process with many discrete and interacting signaling pathways. Apoptosis is about as complex a cellular choreography as one can imagine. Death signals impinge, chromatin cleaves, mitochondria release cell-destroying contents, and membranes undulate and form blebs, eventually shrink-wrapping the shattered cell into neat packages destined for the innards of a phagocyte. Many research grou

Frontlines | Porcine Parts on the Horizon? Courtesy of Scott Bauer Infigen of DeForest, Wis., and BioTransplant of Charlestown, Mass., recently announced the birth of three pigs that mark the next stop on road toward xenotransplantation. The minipigs are clones derived from previous research (J. Betthauser et al., "Production of cloned pigs from in vitro systems," Nat Biotech, 18:1055-9, 2000) as well as knockouts for alpha-1,3-galactosyltransferase (GGTA1), which normally places a particu