NTU Undergraduates' research April 2014 - Biosciences | Page 124

The role of regulatory T cells in cancer
Abstract
Regulatory T cells (Tregs) are crucial within the immune system to down regulate the T cell
immune response and are therefore important in instances such as autoimmune disease.
They are, however the main obstacle tampering successful immunotherapy in cancer.
Recent research reveals that Treg accumulation within the tumour microenvironment is
associated with increased cancer progression and poor prognosis. Tumour trafficking is
thought to be the explanation as to how Tregs travel to the tumour environment, where
they down regulate the activity of T cells, thus interfering with antitumour immunity. It has
been speculated that the suppressive activity of Tregs does in fact come from their cell
surface markers, with examples being FoxpP3, CD25 and CLTA-4. Many studies on mice and
humans prove Tregs directly interfere with antitumour immunity with an example being a
study by Kono et al, which demonstrated a decrease of elevated peripheral Tregs back to
the normal following the resection of a gastric cancer. Evidence to support that Tregs play a
role in cancer has lead on to the development of many cancer therapies and treatment.
Many of which involve methods to reduce Treg accumulation by destruction of their cell
surface markers. It has been made apparent that the more knowledge we have on Tregs
within cancer the better chance we have in finding clinical treatments to cure the disease.