For decades the war on cancer has showed the public
extensive research with little glimpses of hope for a cure. In this post I hope
to explain the complexities that are involved in the research of curing cancer.
Cancer is very, very difficult to understand. The idea of
one cure for cancer is naïve. There are over 200 different types of cancers,
all with their own characteristics making one case different from the next.
These tiny differences in our genetic make-up not only effect the progression
of the disease but the treatment and medication required as well.
Cancer cells grow and divide picking up different
adaptations along the way requiring doctors and researchers to be one step
ahead at all times. As Darwin’s theory of “survival of the fittest” explains the
adaptations needed to survive in the animal kingdom, it is a fitting analogy to
explain how these cancer cells are adapting within the human body to survive
the progression of treatments. Not being bound by genetic coding these cells
seem to take up a mind of their own. Multiplying irrationally, these cells even
duplicate chromosomes in ways never seen before varying vastly from one
another.
Charles Swanton from the Cancer Research UK’s London
Research Institute made a puzzling discovery when looking at four samples of
kidney cancers from a patient. The cells in the cancer at the base of the tumor
had genetically mutated as it spread to different parts of the body. As the
cancer spread throughout the patient’s body it had genetically mutated into completely
different forms of cancer with their own unique traits. This means that this
complex diversity of cells will require multiple different treatments to put
the cancer into remission. This discovery may have answered the question of why
some treatments work at first but some become treatment resistant.
Swanton discovered over 128 different mutations throughout
the four different samples. One third of the mutations were common to all of
the samples yet one fourth were unique to a single sample. In addition the
different samples although taken from a same mass shared some similar genes but
had adapted into two different evolutionary paths. By focusing on the
similarities within the genetic code of the samples researchers can find the
originating tumor and start treatment there. This has shown promising results
in patients with kidney cancer who have had the main tumor removed; researchers
think that by taking the base of the evolutionary path will cause environmental
strain on the remaining tumor cells. These remaining cells are no longer “fit”
for the environment and have less chance of survival.
“It seems tumors depend upon these special changes to keep
living and growing and we need to be smart about targeting these key changes,”
said Dr. Lisa Diller of Harvard Medical School in Boston. “ We need to define
the beating heart of a tumor and figure out how to aim our drugs straight at
it.” (Shukla, 2012)
As research progresses other innovative techniques has been
developed to aid in this ongoing battle. As I have previously discussed in my
post “customized
medicine” the idea of personalizing medicine, testing, as well as
diagnostics seems to be in synch with developing research. Carla Leslie is one
example of a success story of personalized medicine treatment. Doctors at the
MD Anderson Cancer Center in Huston treated her stage 3C breast cancer with
chemotherapy and a drug called Herceptin.
The stage at which the cancer was in has mortality rate of up to 60
percent over five years. They chose Herceptin out of many potential drugs due
to her specific genetic composition. As of today Carla’s cancer is still in
remission. This case is laying an important foundation in this research. With
more use technique more success stories like Carla’s are possible.
Researchers are starting to
understand that taking a single biopsy of a tumor is not as effective as they
once thought. Taking multiple samples from different locations from the tumor
shows the cancers progression and further mutation. Looking for similarities
within the genetic code researchers can pinpoint the origin of the tumor and
begin the treatment at the source. Personalized medicine will come into play to
help effectively target remaining mutations that chemotherapy by itself falls
short. The old ideology that a “one size
fits all” treatment for cancer is being replaced with newer thinking.
Specialized medicine targeting individuals and their specific genetic requirements
shows promise for the successful treatment of cancer in the future.
Shukla, R. (2012) Moving Target: Why a Cancer “Cure” is So
Elusive. ABC News.
Retrieved from http://abcnews.go.com/Health/CancerPreventionAndTreatment/moving-target-cancer-cure-elusive/story?id=15862910#.UWYLuCvwJ5k
Young, E. (2012) World within a tumor – study shows how
complex cancer can be.
National Geographic. Retrieved from
http://phenomena.nationalgeographic.com/2012/03/07/a-world-within-a-tumour-new-study-shows-just-how-complex-cancer-can-be/
You do a great job writing for the general public on such a topic as cancer. I had no idea there were 200+ types, but that does make sense. My main request would be to mention sources right in the early paragraph where this type of data shows up that isn't common knowledge. Even if you know it, you need to provide scaffolding to show readers which source (here, Young or Shukla) was the provider of that data.
ReplyDeleteIf you want to expand this further, interview me! I have been with my mom through first chemotherapy and now immunotherapy, especially since her cancer diagnosis was changed from stomach to metastatic melanoma found in the stomach and lymph nodes. They had to take 3 different biopsies to make sure they had the right cancer as sometimes typing is difficult at best.