Mary Carmen Zuñiga
Currently a junior at Northern Arizona University and
working towards a Bachelor's degree in Biology with a minor in Chemistry, I
want to pursue a medical and research career in the oncology field.
As a URM scholar, my research deals with depleted uranium
and UVB-light cytotoxicity and mutagenics. However, my range of interests
Molecular and chemical mechanisms for cancer
- uranium and UV-light mechanisms of damaging
skin cells in ways that may lead to cancer
- skin cancer
- mutagenesis, UV-light induction, and molecular
Nanotechnology applied to cancer research
- self-propelled micro- and nano-scale devices and
their biomedical applications
- photolithography used for creation of
micro-scale grippers potential medical applications
- 3-D cell culture and tissue engineering
- diabetes Mellitus
- genetics and hereditary implications
Cellular damage and DNA-mutations induced by
depleted uranium and UVB-light in skin cells
Mentored by Dr.
Diane Stearns and supported by the Undergraduate Research Mentoring, I started working with depleted uranium and skin cells during
the fall 2010. Our laboratory focuses on how some metals may damage DNA in ways
that may lead to cancer.
What is depleted uranium?
Depleted uranium (DU) is the leftover uranium after 235-U
has been collected to be used for nuclear purposes. Because of its composition,
it is the least radioactive form of uranium. However, its repercussions in
society are highly controversial because this form of uranium is regularly used
in the military, especially for tank armor because of its high density and
because it is hard to penetrate.
People who work in the military can be exposed to depleted
uranium by inhalation of the particles after impact and also by embedding of
DU-containing shrapnel within the skin. In addition, civilians are subjects of
exposure to DU through contaminated water and soil.
Why depleted uranium?
According to the National Cancer Institute, "at least
two thirds of all the cases of cancer in the United States are due to a wide
variety of natural and man-made substances in the environment," and some
of these carcinogens are metals such as uranium and chromium, which are the
metals we study in our lab.
The uranyl ion (UO22+) is known to be photoactivated by
UVB-light in the 300-400 nm range. When it is photoactivated, it creates an
oxygen-centered radical bound to uranium(V). However, none has studied what
this can cause at the DNA level. This research aims to look into the
effects of the photoactivated uranyl ion at the molecular level in human skin.
It is proposed that its photoactivation by UVB light may contribute to the
uranium toxicity in human skin.
My research questions
- How much cell damage can DU cause in skin cells?
- How much cell damage can UVB-light cause in skin
- What mutations are induced by both factors
combined (DU + UVB)?
Answering the questions
In order to answer my research questions, I am using cell
culture and molecular techniques. My URM prospectus addresses the materials and
methods used to answer the questions and any other details about the project.