Study suggests cancer may vary among races
Asian American stomach cancer patients have tumors with
biological traits that differ from tumors in non-Asians, which may
explain why they have better survival rates, according to a UC
Irvine College of Medicine study.
The findings, which appear in the November issue of Cancer, may
be the first to link differences in tumor biology to survival rates
among ethnic groups and provide insight into why certain tumors
affect some populations more ““ and more severely ““ than
others.
Hoda Anton-Culver, professor of epidemiology, and Charles
Theuer, assistant professor of surgery, led a team that examined
records from 3,770 Asian and non-Asian stomach cancer patients in
Southern California. They found survival rates of Asians with
stomach cancer were far higher than any other ethnic group and that
tumors in Asians did not invade normal tissues as aggressively
.
“The differences in cancer rates … have been attributed
in the past to varying diet, diagnostic methods and more radical
surgical techniques by Asian doctors,” Anton-Culver said.
“But we found that Asian Americans with the same stage of
disease who received the same health care as non-Asians still
exhibited superior survival rates. The variation indicates
diagnosis, screening and treatment will have to accommodate
biological differences in the way cancer attacks certain ethnic
groups.”
The team is looking at how the biology of cancer cells can
create this protective effect in certain populations and how genes
and molecules control the behavior of cancer cells.
Researchers discover natural medicine
A UC Irvine College of Medicine research team has found a
marijuana-like chemical that occurs naturally in the body may
control coughing and various respiratory functions.
The finding, which appears in the Nov. 2 issue of Nature,
provides the first insight into the causes of certain types of
coughing and may result in the development of new treatments to
combat chronic, dry or nonproductive coughing spells.
Daniele Piomelli, professor of pharmacology, and his colleagues
found a naturally occurring neurotransmitter related to marijuana
called anandamide binding to receptors on muscle cells in the
lungs, controlling the lungs’ reactions to chemical agents
that trigger dry coughing.
“Experiments with patients in the 1970s showed that the
active ingredient in marijuana helped some patients with chronic
asthma, but actually made the symptoms worse in several
patients,” Piomelli said. “Naturally occurring
anandamide in the lung controls the lung’s ability either to
constrict and cough or to dilate and ease breathing.”
Types of chronic dry coughing affected by the body’s
anandamide system are seen in people with some cancers, chronic
obstructive pulmonary disease, hay fever and asthma.
New DNA test used to track Africanized bees
Researchers from the Department of Entomology at the University
of California, Davis are tracking the progress of Africanized
“killer bees” across California.
Scientists developed a genetic test which allows them to
distinguish Africanized bees from those naturally present in
California, according to Robert Page, chair of the entomology
department at UC Davis.
Genetic analysis in 1991 showed some bees carried a genetic type
that could not be distinguished from the African variety.
The marker is carried on mitochondrial DNA, which is inherited
only through the queen bee.
Working with researchers in Mexico, Page’s lab developed a
DNA fingerprinting test to distinguish these varieties.
Compiled from Daily Bruin wire services.