from the California Institute of Technology, with support from the
National Science Foundation (NSF), have developed conditional small
RNA molecules that could treat
cancer cells without causing negative side effects.
is a personal disease that varies with each case and is based on
one's own environmental and genetic factors. It is normally treated
with chemotherapy, which consists of giving patients one or more
types of drugs in hopes of this diagnosing and treating cancer cells.
The problem with chemotherapy is that it is not selective enough, in
that taking a drug which kills fast-growing tumor cells will also
kill cells in the hair follicle, due to the fact that cells in the
hair follicle are fast-growing as well. This is what leads to hair
loss while going through chemotherapy treatments.
now, Niles Pierce, co-author of this study, along with his team, have
created the conditional small RNA molecules to separate the diagnosis
steps by utilizing characteristics found in our DNA and RNA.
This will help target cancer cells only, and leave unaffected cells
molecules are able to detect a mutation within a cancer cell, and
then change conformation to activate a therapeutic response in the
cancer cell, while remaining inactive in cells that lack the cancer
mutation," said Pierce.
performs certain tasks in a cell, such as playing the messenger role
and switching to communicate and watch over which genes are expressed
in a cell "at any given time." By performing such tasks,
RNA help to keep cells alive and healthy.
RNAs, which are a particular class of RNAs, are what Pierce and his
team are relying on for their new treatment. Small RNAs are less than
30 base pairs in length, where an average gene is thousands of base
pairs long. In this study, two types of small RNAs are used because
they are involved in many processes "that maintain life,"
and they structurally mimic small
processes that naturally occur within our cells. The first
small RNA opens up if there is a cancer mutation. If there is, a
hidden signal is exposed within the small RNA. After it opens, the
second small RNA attaches to it and triggers a chain reaction where
RNA molecules continuously come together to form a longer chain. The
longer the chain, the better because longer chains "trick"
cells into thinking they're being attacked by a virus, and it causes
cancer cells to self-destruct.
decoupling diagnosis and treatment, we can create molecules that are
both highly selective and highly effective in killing
cancer cells," said Pierce. "Conceptually, small
conditional RNAs have the potential to transform cancer treatment
because they can change what we can expect from a molecule. Many
years of work remain to establish whether this conceptual promise can
be realized in human patients."
study was published in Proceedings
of the National Academy of Sciences.