New Hope for Improved Treatment of Small Cell Lung
Cancer Found in Study of Senior Citizens
TGen-Scottsdale Healthcare researchers make
breakthrough: MicroRNAs are key to identifying resistant to 'first-line'
chemotherapy
Types of Lung Cancer
The types of lung cancer are
treated differently. The most common types are named for how the
lung cancer cells look under a microscope:
Small cell lung cancer: About 13 percent of lung
cancers are small cell lung cancers. This type tends to spread
quickly.
Non-small cell lung cancer: Most lung cancers (about
87 percent) are non-small cell lung cancers. This type spreads
more slowly than small cell lung cancer.
Jan. 13, 2010 - A new study of senior citizens with
small cell lung cancer the rapidly spreading type of lung cancer has
discovered a way to predict which patients with SCLC may be resistant to
first-line chemotherapy. This breakthrough is critical since patients
with SCLC often do not get a second chance at therapies to combat this
aggressive type of cancer.
Researchers for TGen Clinical Research Services at
Scottsdale Healthcare (TCRS) will present their study, today in San
Diego at a joint conference of the American Association for Cancer
Research (AACR) and the International Association for the Study of Lung
Cancer (IASLC).
"For patients with small cell lung cancer, there
are really only about two chemotherapy options. We need to be more
precise with our treatments and identify who is going to be resistant up
front in order to design better clinical trials that will identify
effective therapies for these at-risk patients," said Dr. Glen J. Weiss,
director of Thoracic Oncology at TCRS, who presented the findings at
AACR-IASLC's Joint Conference on Molecular Origins of Lung Cancer.
TCRS is a partnership between the Translational
Genomics Research Institute (TGen) and Scottsdale Healthcare that
enables laboratory discoveries to be quickly turned into targeted
therapies that can be tested with patients at the Virginia G. Piper
Cancer Center in Scottsdale.
Of the nearly 32,000 new cases of SCLC diagnosed in
the U.S. every year, between 15 and 30 percent will be chemoresistant to
first-line therapy, or about 6,500 SCLC patients annually.
SCLC tends to
spread much more quickly than non-small cell lung cancer. There are
three types of SCLC: small cell carcinoma (oat cell cancer), mixed small
cell/large cell carcinoma, and combined small cell carcinoma.
The study led by Dr. Weiss proposed to look at how
to best identify those SCLC patients who would be chemoresistant. By
profiling tumors, he and a team of TGen researchers identified at least
three tumor microRNAs that appear to predict small cell lung cancer
patients who will prove resistant to first-line chemotherapy. In
addition to researchers at TGen, Dr. Weiss was assisted by scientists at
the Scottsdale Clinical Research Institute and the Van Andel Research
Institute.
MicroRNAs are small molecules that regulate gene
expression in the process of making proteins as well as directing the
structure and function of cells. This regulation usually prevents cancer
and other diseases.
Weiss and colleagues evaluated 34 patients at with
varying stages of SCLC. The median age of the patients was 69.1 years,
and half were men. All 34 received systemic chemotherapy. There were two
complete responses and 13 partial responses. Two patients had stable
disease and four had progressive disease.
Three microRNAs biomarkers were identified as being
closely linked with chemoresistance: miR-92a-2*, miR-147, and
miR-574-5p. Although 47 percent of the patients presented with
hypertension and 32 percent presented with emphysema or chronic
obstructive pulmonary disease, neither of these co-morbidities were
linked with chemoresistance.
These findings should help clinicians design better
drug trials, the researchers say.
Editors Notes:
Dr. Weiss has received grant funding to support
this work from these charitable organizations: Sylvia-Chase Foundation,
American Cancer Society, IBIS Foundation of Arizona, and the TGen
Foundation.
Research title: Tumor MicroRNA Biomarkers
Associated with De Novo Chemoresistance in Small Cell Lung Cancer.
About TGen
The Translational Genomics Research Institute (TGen)
is a non-profit organization dedicated to conducting groundbreaking
research with life changing results. Research at TGen is focused on
helping patients with diseases such as cancer, neurological disorders
and diabetes. TGen is on the cutting edge of translational research
where investigators are able to unravel the genetic components of common
and complex diseases. Working with collaborators in the scientific and
medical communities, TGen believes it can make a substantial
contribution to the efficiency and effectiveness of the translational
process. For more information, visit:
www.tgen.org.
About the Virginia G. Piper Cancer Center at
Scottsdale Healthcare
The Virginia G. Piper Cancer Center at Scottsdale
Healthcare offers prevention, diagnosis, treatment, research and support
services in its facilities at the Scottsdale Healthcare Shea Medical
Center, attracting patients from across Arizona and the U.S. Scottsdale
Healthcare is the not-for-profit parent organization of the Scottsdale
Healthcare Shea Medical Center, Scottsdale Healthcare Osborn Medical
Center and Scottsdale Healthcare Thompson Peak Hospital, Virginia G.
Piper Cancer Center, Scottsdale Clinical Research Institute and
Scottsdale Healthcare Foundation. For additional information, visit
www.shc.org.
Lung cancer is one of the most common cancers in
the world. It is a leading cause of cancer death in men and women in the
United States. Cigarette smoking causes most lung cancers. The more
cigarettes you smoke per day and the earlier you started smoking, the
greater your risk of lung cancer. High levels of pollution, radiation
and asbestos exposure may also increase risk.
Common symptoms of lung cancer include
● A cough that doesn't go away and gets worse over time
● Constant chest pain
● Coughing up blood
● Shortness of breath, wheezing, or hoarseness
● Repeated problems with pneumonia or bronchitis
● Swelling of the neck and face
● Loss of appetite or weight loss
● Fatigue
There are many types of lung cancer. Each type of
lung cancer grows and spreads in different ways and is treated
differently. Treatment also depends on the stage, or how advanced it is.
Treatment may include chemotherapy, radiation and surgery.
Cancer Cells
Cancer begins in cells, the building blocks that
make up tissues. Tissues make up the organs of the body.
Normal, healthy cells grow and divide to form new
cells as the body needs them. When normal cells grow old or become
damaged, they die, and new cells take their place.
Sometimes, this orderly process goes wrong. New
cells form when the body does not need them, and old or damaged cells do
not die as they should. The build-up of extra cells often forms a mass
of tissue called a growth or
tumor.
Tumor cells can be
benign (not cancer) or
malignant (cancer). Benign tumor cells are usually not as harmful as
malignant tumor cells:
>> Benign lung tumors ● are rarely a threat to life
● usually do not need to be removed
● do not invade the tissues around them
● do not spread to other parts of the body
>> Malignant lung tumors ● may be a threat to life
● may grow back after being removed
● can invade nearby tissues and organs
● can spread to other parts of the body
Cancer cells spread by breaking away from the
original tumor. They enter blood vessels or
lymph vessels, which branch into all the tissues of the body. The
cancer cells attach to other organs and form new tumors that may damage
those organs. The spread of cancer is called
metastasis.
Types of Lung Cancer
The pathologist checks the sputum, pleural fluid,
tissue, or other samples for cancer cells. If cancer is found, the
pathologist reports the type. The types of lung cancer are treated
differently. The most common types are named for how the lung cancer
cells look under a microscope:
Small cell lung cancer: About 13 percent of lung cancers are small
cell lung cancers. This type tends to spread quickly.
Non-small cell lung cancer: Most lung cancers (about 87 percent) are
non-small cell lung cancers. This type spreads more slowly than small
cell lung cancer.
