Why we funded it
Dr Parker's previous research identified two tumour markers
(VEGF and HIF-1 alpha) that seemed to identify men at higher risk
of cancer recurrence after radiotherapy treatment. If confirmed in
this larger study, these markers could help identify men for whom
standard radiotherapy is likely to be less successful and who would
be suitable for trials of more intensive treatment.
Scientific title
Evaluating tissue biomarkers of outcome: secondary analyses of
MRC RT01 and PR07.
Research project summary
At present, all patients receiving radiotherapy are given the
same dose. This research project aims to find better ways to
predict prostate cancer treatment outcome so that in future,
specific molecules referred to as 'markers' in the prostate cancer
biopsy tissue could be identified to determine the most appropriate
dose for each individual patient. Additionally, given that higher
doses of radiotherapy improve disease control but also increase
treatment side effects, there is a need to find markers that
predict which patients will benefit from higher doses. Markers such
as these could also identify patients who are unlikely to be cured
by radiotherapy, and who would therefore be suitable for other
treatment strategies.
Dr Chris Parker and his research team will begin by identifying
patients for whom standard treatment has a poor outcome, and thus
would be suitable for clinical trials of more aggressive
treatments. For this, they will use prostate biopsy samples
following ethical consent (further info below), taken between 1995
and 2005, from 1400 men who took part in two national prostate
cancer radiotherapy trials. Information will be available regarding
what has happened to these 1400 men, so it will be known in each
case whether or not treatment was successful.
To enable best use of the tissue samples, the researchers will
construct a 'tissue microarray' (TMA) - this is a technique which
involves putting many tissue samples on one slide so they can be
further investigated with different tests simultaneously.
Using the TMA, the team will test three promising markers (used in
previous studies), to determine whether or not they can predict
treatment outcome. These markers are associated either with tumour
oxygen levels and blood supply, or with the mechanism of cell
death.
The research team have based these studies on their previous
findings from 200 prostate cancer cases in which they identified
two markers which were associated with recurrence of cancer after
treatment. They also identified a third marker that determined
whether patients were more likely to benefit from higher doses of
radiotherapy (further info below). The confirmation of their
previous findings in another 1400 tissue samples would further
validate these markers towards a method for individualising
treatments for patients.
See more information...