February 8,2005
news @michigandaily.com

SCIENCE

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AGAUNIST OCAiwcrR

Recently developed medical treatments move closer to defeating the disease

Lymphoma
drug proves
effective
By Brandon Harig
Daily Staff Reporter
Hair loss, nausea and vomiting are just some of the pain-
ful side effects cancer patients endure when they undergo
chemotherapy to treat their illness. But a new drug may pro-
vide patients afflicted with lymphoma - one of the most
prevalent forms of cancer - with a more effective treatment
without having to bear chemotherapy's physical costs.
A study by researchers of the University's Comprehen-
sive Cancer Center, published Feb. 3 in the New England
Journal of Medicine, showed the effectiveness of a new
drug called Bexxar on non-Hodgkin's lymphoma patients.
Lymphoma, a cancer of the blood, bone marrow and
lymph nodes - part of the human immune system - has
thirty different variations.
Typically treated with chemotherapy to force it
into remission, lymphoma may require more than six
months of cancer therapy. According to the Ameri-
can Cancer Society, lymphoma is one of the fastest-
growing causes of cancer mortality and the sixth
leading form of cancer death in the United States.
The University's study focused on 76 patients
diagnosed with advanced-stage follicular lymphoma
- the most common variation of non-Hodgkin's
lymphoma. Treated with Bexxar before any other
treatment, the patients recovered with amazing
results, with 75 percent showing signs of complete
lymphoma remission. All the more significant is that
advanced follicular lymphoma is commonly thought
to be incurable.
Mark Kaminski, head of the study and director of
the University's Lymphoma/Leukemia Program, said
in a statement, "(the results) support the notion that
there's a real possibility of putting chemotherapy on
the back burner for this disease." Kaminski devel-
oped Bexxar with former University Prof. Richard
Wahl, now at Johns Hopkins University. The drug
received approval from the Food and Drug Adminis-
tration in June 2003.
Compared to traditional chemotherapy, Bexxar
produces a much smaller range of negative effects.
Kaminski said Bexxar's most important advantage
is that the drug offers "shorter treatment and less
toxicity" than chemotherapy. While the price of the
drug is comparable to that of chemotherapy, the time
required for treatment is not. While chemotherapy
may take half a year or more, Bexxar therapy is con-
ducted over only one to two weeks.
Part of the drug's effectiveness may come from
how it is delivered, Kaminski said. Chemotherapy
works by targeting cells that are rapidly dividing - a
characteristic of cancerous cells - and restricts their
growth. The problem with the treatment is that the
chemotherapy may also target, albeit erroneously,
normal cells within the body and cause negative side
effects. Though the body is able to repair these cells,
the damage can make treatment difficult and affect
the patient's health and mood.
Kaminski said the difference with Bexxar is the
drug directly attacks cancer cells. Composed of both
antibodies that can seek out cancer cells and radioac-
tive iodine 131, Bexxar works by traveling through
the patient's bloodstream. The antibodies then deliv-
er the iodine to the cancer cells, killing the diseased
cells off with the radiation from the iodine. As a
result, fewer normal cells are damaged and the treat-
ment is less hazardous to patient's health.
As of now, the drug is available for patients who
have previously been treated with chemotherapy
for low-grade or follicular lymphoma. The drug is
marketed in the United States by the pharmaceutical
company GlaxoSmithKline.

New uses For
old breast
cancer drugs
By Sunil Patel
For the Daily
A new class of drugs may prove to be the next power-
ful weapon in the fight against breast cancer.
While one of the most popular treatments for breast
cancer is the use of the drug tamoxifen, four large clini-
cal trials have shown that compounds called aromatase
inhibitors have a slight advantage - 4 to 5 percent
- over tamoxifen in preventing tumor recurrence, said
Daniel Hayes, clinical director of the University's breast
oncology program.
This advantage is small but significant. In earlier tri-
als, AIs were successful in patients whose cancer had
already metastasized, or spread to other parts of the
body. These new trials suggest that AIs may be useful
in preventing the spread from occurring.
According to the American Cancer Society, breast
cancer kills more than 40,000 people each year in the
United States. Although incidences have been increasing
over the last 50 or 60 years, mortality has been dropping
"relatively steeply" in the United States, Hayes said.
One reason for this drop is adjuvant therapy, which
supplements the treatment of the breast with treatment
of the entire body. Aside from chemotherapy, there is
also hormone therapy, which targets hormones cancer
cells need to grow. Treatment with tamoxifen and AIs

are examples of therapy that
Hayes said the
advantage of
Als is pretty
small, and
so far, they
have seen
no difference
in survival.
On the other hand, AIs -

target the hormone estro-
gen. More than half of
breast cancers require:
estrogen, and these can-
cer cells have estrogen
receptors, which are
detectable by doctors.
"If you think of a can-
cer cell like an automo-
bile," Hayes said, "the
estrogen receptor is like
a gas tank, and estrogen
is like gasoline."
Tamoxifen, which
blocks the estrogen
receptor, is like putting
water in the gas tank
to screw up the engine,'
Hayes said.
which include Arimidex,

ANTIBODY INDUCES APOPTOSIS,
OR CELL DISINTEGRATION, AND
DELIVERS RADIATION TO THE CELL.
HOW BEXXAR WORKS
GRAPHIC BY MATTHEW DANIELS
SCI ENCE FACTS
Non-Hodgkins lymphoma, a cancer of the
lymphatic system, attacks the body's immune system
Unlike the more easily curable Hodgkins disease,
non-Hodgkins lymphoma is the sixth leading
cause of cancer death in the United States.

Aromasin and Femara - act at an earlier point in the
process - they stop the estrogen from being made in
the first place. Because of their unique point of attack,
they are only effective in postmenopausal women.
Hayes said the advantage of AIs is pretty small, and
so far, they have seen no difference in survival. They
do, however, prevent tumor recurrence as well as or bet-
ter than tamoxifen. By stopping the spread of cancer to
the rest of the body - as well as keeping it from coming
back - they increase the patients' quality of life. This
may lead to an increase in survival, but a difference may
not be apparent after the short duration of the study.
For a patient with a good prognosis and some sign
of osteoporosis, Hayes recommends tamoxifen because
AIs elevate the risk of osteoporosis. For a patient with
a bad prognosis and no sign of osteoporosis, however,
Hayes thinks AIs are a good choice because of their,
effectiveness in preventing tumor recurrence and metas-
tasis.
Despite the increased risk of osteoporosis, AIs lower,
the risk of uterine cancer and blood clots, Hayes said.
Tamoxifen has been around for thirty years. "I think"
we know everything bad about tamoxifen that we're
gonna know," Hayes said. AIs, on the other hand, have
only been around for ten years, and the early trials were
on patients who already had metastatic cancers.
"We may see things from these drugs that we don't
know about in the next five or ten years," Hayes said.

" Prof says 200 solar masses may be as big as stars can get

The recent findings result
from the data sets of various
star cluster data
By Kingson Man
Daily Staff Reporter
Everybody knows that whales in the ocean are big,
but do they ever stop growing? Given the opportunity
and the good supply, would whales keep growing with-
out limit, or would some intrinsic quality check their
size at some leviathan amount?
This was the analogy that Sally Oey, an assistant pro-
fessor in the University's Department of Astronomy,
wrestled with in the course of determining the size lim-
its of the most massive stars in the universe.
Working with C.J. Clarke, a researcher at Oxford
University, the two may have a figure for the maximum
size of stars, if not whales: between 120 to 200 times
the mass of our own sun.
In the pecking order of stars in the universe, our sun
is only medium-sized. Not too big and not too small, it
fits in the middle of charts that rank stars according to

Their analysis combed through the published
data sets of star sizes in many different clusters and
found that the Initial Mass Function, or the curve that
describes the probabilities of finding stars of different
sizes, didn't hold for very massive stars.
Instead of just becoming very rarely seen, very mas-
sive stars weren't found in their observations. The IMF
"breaks down at 150 solar masses," Oey said.
Previously, stars of up to 1000 solar masses were
thought to exist. Subsequent observations by the Hub-
ble Space Telescope were able to distinguish that these
"stars" were actually combinations of many smaller
stars in the same patch of sky.
These findings could hold implications for the way
mass calculations are done for remote areas of the uni-
verse. Because
small stars
greatly outnum-
Instead of just ber their larger
counterparts,
becoming very small stars make
up most of the
rarely seen, very « oto h
f ymass of a stellar
massive stars region.
"If we overes-
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