Agendia & Collaborators Publish Key MammaPrint Paper in Nature Cell Biology

Study Once More Underpins the Clinical Value of FDA-cleared Breast Cancer Recurrence Assay

IRVINE, California, and AMSTERDAM, December 22, 2010 - Agendia, a world leader in molecular cancer diagnostics,
announced today that together with several groups of scientific collaborators
it has identified a major role for TSPYL5, one of its MammaPrint breast
cancer prognosis genes, in the genesis of breast cancer. The study entitled:
"TSPYL5 suppresses p53 levels and function by physical interaction with
USP7", was published today in Nature Cell Biology, one of the foremost
scientific journals.

The study provides further proof of the superiority of the
unbiased whole genome discovery process on which MammaPrint is based. The 70
genes that constitute the MammaPrint signature were arrived at after
comparison of full genome gene expression profiles of a large number of
breast tumors. In 2002, when the first landmark papers on MammaPrint were
published in the New England Medical Journal and Nature, the individual
function of nearly half of the 70 genes was unknown, including the TSPYL5
gene. Despite this, it was clear that MammaPrint offered the strongest
prognostic evidence of any molecular diagnostic assay for breast cancer
recurrence and is able to identify chemotherapy-sensitive metastasis risk
with 94% accuracy. The discovery process commonly used today by developers of
molecular diagnostic assays relies on the so-called candidate gene approach,
in which genes are selected based what is known from the scientific
literature and expert opinion at the specific date of development. By its
nature this approach has important limitations, since it ignores the wealth
of information in the human genome, such as the TSPYL5 gene, that, even if
unexplained, still plays a pivotal role in disease processes.

The paper in Nature Cell Biology describes for the first time
the function of the TSPYL5 gene, and specifically its crucial interaction
with p53, one of the best-described tumor suppressor genes. By suppressing
p53, TSPYL5 seems to disarm one of the key genes responsible for combating
tumor development, and the authors show that TSPYL5 is an independent poor
prognosis marker in breast cancer. The TSPYL5 gene and another previously
unknown MammaPrint gene, metadherin (MTDH), which was also recently found to
mediate metastasis and chemoresistance, are not included in other breast
cancer recurrence assays and in hindsight provide a scientific rationale for
MammaPrint's unprecedented clinical utility.

To access the paper, please go to:
www.nature.com/ncb/journal/vaop/ncurrent/abs/ncb2142.html

About MammaPrint(R)

MammaPrint is the first and only breast cancer recurrence test
cleared by the U.S. Food and Drug Administration (FDA). FDA clearance
requires clinical and analytical validation and reporting systems to ensure
patient safety issues are addressed. Highly accurate, MammaPrint identifies
patients with early metastasis risk - patients who are likely to develop
metastases within five years following surgery. Several authoritative studies
have shown that chemotherapy particularly reduces early metastasis risk. In
planning treatment, the MammaPrint test results provide doctors with a clear
rationale to assess the benefit of chemotherapy in addition to other clinical
information and pathology tests. All MammaPrint tests are conducted in
Agendia's CAP-accredited and CLIA compliant service laboratories.

About Agendia

Agendia is at the forefront of the personalized medicine
revolution, striving to bring more effective, individualized treatments
within reach of patients. Building on a cutting-edge genomics platform for
tumor gene expression profiling, the company's tests help physicians more
accurately tailor cancer treatments. Agendia markets four products, with
several new genomic tests under development. In addition, Agendia
collaborates with pharmaceutical companies to develop highly effective
personalized drugs in the area of oncology. Agendia is based in Irvine,
California, and in Amsterdam, the Netherlands.

Media Contacts: Hans Herklots, +31-20-462-1557 Office, +31-620-083-509, Mobile, hans.herklots at agendia.com; Valerie Carter, Ricochet Public Relations, +1-202-316-0143, Mobile, vcarter at ricochetpr.com