Personalized medicine is a medical model proposing the customization of
healthcare, with all decisions and practices being tailored to the individual
patient by use of genetic or other information. Practical application outside
of long established considerations like a patient's family history, social
circumstances, environment and behaviors are very limited so far and
practically no progress has been made in the last decade.
In
application to cancer treatment it supposed to be used in the following model:
First, analysis
of a type of tumor for any particular patient and then, depending on the
results of the analysis, a use of a particular treatment suitable for the
present type of mutations in the tumor. It sounds logical if we assume that the
tumor is homogen in terms of type of mutations in different areas of tumor.
Biopsy or a biomarker helps to choose the best way of treatment.
The idea was
found so promising
that it concurred the scientific landscape in a couple of years – universities
and Big Pharma invested a lot of resources in order to develop promising modern
drugs and diagnostics for personalized medicine…
And do you
know what? Probably in vain….In this
article is described that:
Intratumor
heterogeneity can lead to underestimation of the tumor genomics landscape portrayed
from single tumor-biopsy samples and may present major challenges to personalized-medicine
and biomarker development. Intratumor heterogeneity, associated with heterogeneous
protein function, may foster tumor adaptation and therapeutic failure through
Darwinian selection.
In simple words
the authors has found that the tumor is heterogenic in terms of mutations – in different
parts of a tumor and metastases can be found different types of mutations which
practically means that it is extremely hard (if even possible) to correctly
specify the type of cancer on the basis of biopsy specimen or a biomarker
analyses. And moreover – the cancer can be hardly specified in terms of a
single mutational origin. And it looks like that the presented research is a real wild-card which can make a tremendous impact on the future drug development process in general and on personalized medicine in particular. Well, it is not personal, just science.
No comments:
Post a Comment