By David N. Leff
Editor's note: Science Scan is a round-up of recently published biotechnology-related research:
A man's risk of prostate cancer is higher if his brother has the disease than if his father had it.
This inheritance pattern is typical of genes that reside on the human X chromosome, and so are passed from mothers to sons. Muscular dystrophy and hemophilia are examples.
Now, add prostate cancer to the list of X-linked, male-only inherited afflictions. An international consortium of gene-mappers, co-directed by the U.S. National Human Genome Research Institute (NHGRI) at the National Institutes of Health, in Bethesda, Md., reported their finding in Nature Genetics for October 1998.
The task force studied more than 1,500 men with prostate cancer from over 360 families prone to the disease. They have named the still-to-be-isolated gene HPCX, standing for human prostate cancer X. Besides NHGRI, the team includes five academic and clinical institutions in the U.S., Finland and Sweden.
Having mapped the location of HPCX, the researchers are now looking at several candidate genes in the region. "There's none that jumps out at us and screams that it's the gene we're looking for," observed the project's co-director, William Isaacs, of Johns Hopkins University, in Baltimore.
NHGRI's director, Francis Collins, pointed out that identifying the precise gene and its cancer-causing mutations "will lead to better abilities to predict which men are at highest risk. This can allow them to be carefully watched for early signs of prostate cancer." Such early diagnosis may be life-saving, Collins said. "In the longer term, understanding the molecular causes of prostate cancer is expected to usher in a new generation of more effective therapies," he said.
One difficulty of tracing the inheritance pattern of this disease is that it's almost always diagnosed in men over the age of 60, by which time their parents and grandparents have died, and cannot be studied.
Archived Blood Hints That In Utero Infection and Autoimmunity Are Likely Causes Of Cerebral Palsy
Medical books traditionally attribute cerebral palsy (CP) to suffocation or injury during the birth process. Yet, even though obstetrical methods have improved in recent decades, the number of full-term infants who develop CP hasn't decreased.
Now, new research reports evidence that inflammation and clotting abnormalities during gestation may be important causes of CP in babies delivered at full term — as are half of all children with this disorder. From one to two in 1,000 babies are born with CP, and up to one in 100 premature infants have the disorder.
CP affects about 500,000 people in the U.S. They are afflicted with faulty development or damage to the motor areas of the brain. A victim's arms and legs are mainly affected, leading to movement disabilities and other symptoms.
Because the disorder usually can't be diagnosed before a child is two years old, pinning down exact causes of CP has been frustrated. But in the state of California, a Newborn Screening Program offered a way around this roadblock. It stores blood samples from all newborns in the state to screen for metabolic disorders.
Researchers from the California program, George Washington University Medical Center, in Washington, D.C., and the National Institute of Neurological Disorders and Stroke (NINDS), in Bethesda, Md., analyzed blood samples from 31 neonates who had gone on to develop CP, and 65 who had not. They detected high concentrations of five different cytokines — tumor necrosis factor, RANTES, and interleukins 1, 8 and 9, as well as clotting-factor proteins.
Their report appears in the October 1998 Annals of Neurology.
The study's lead author, pediatric neurologist Karin Nelson, at NINDS, suggested that these findings might betoken autoimmune disorders or chronic infection in the womb. Cytokines, she observed, "are usually found only in very small amounts in the blood. What they are doing in relatively large amounts in these children with CP is a mystery." These results must now be replicated in a larger test population.
Anthrax Spores 'Explode' When Treated With BCTP, A Nano-Scale Emulsion Developed By Novavax
While the U.S. Defense Department is placing some of its chips on a vaccine under development against biowarfare attack by anthrax, its Defense Advanced Research Projects Agency (DARPA) is testing several other candidate antidotes, including an emulsion called BCTP.
This proprietary product was developed by Novavax Inc., at its laboratories in Columbia, Md., by the firm's chief scientific officer, Craig Wright.
In a preclinical in vivo study by internist James Baker Jr. at the University of Michigan Medical Center, in Ann Arbor, BCTP rescued mice from direct attack by anthrax. Baker reported the results late last month in a poster session at the annual meeting of the Interscience Conference on Antimicrobial Agents and Chemotherapy, in San Diego, Calif.
Mice with simulated wounds infected with Bacillus anthracis and then treated with BCTP had 95 percent reduced skin lesions and swelling, compared to untreated control animals, of which 80 percent died. In a prior in vitro experiment, Baker reported, the emulsion inactivated more than 90 percent of B. anthracis spores, after four hours of incubation.
"One of the most remarkable characteristics of this material," he said, "is its ability to rapidly destroy a wide variety of dangerous bacteria and viruses, while remaining non-toxic to people, animals and the environment."
Inventor Wright explained the components in BCTP "form a nanoemulsion of tiny lipid droplets suspended in solvent. These lipids fuse with anthrax spores, which then revert to the pathogen's active state. During this four-to-five-hour process," he continued, "the spore's tough outer membrane changes, and the emulsion's detergent then degrades its interior contents. The spores seem to explode."
Baker said countries hostile to the U.S. have developed strains of anthrax that are resistant to antibiotics and existing vaccines. With funding from DARPA's Unconventional Pathogen Countermeasures Program, he plans to conduct new studies evaluating BCTP's effectiveness against inhaled anthrax spores, as well as other bacteria and enveloped viruses. *