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developed 14-gene metastasis score that predicts distant metastasis in breast cancer
research subjects without systemic treatment has now been applied to Tamoxifen-
treated research subjects. Many of the genes in this constellation are involved in
the p53 and TNF signaling pathways and are implicated in cancer proliferation.
The absence of the estrogen receptor gene in the constellation increases the confi -
dence that this information complements routinely assayed estrogen receptor lev-
els determined by immunohistochemistry. The test can be used as a predictor of
distant metastasis in Tamoxifen ® -treated breast cancer patients. A key fi nding is
the calculation of a Metastasis Score for breast cancer that predicts a 3.5-fold dif-
ference in risk between the 20 % of women at highest risk and the 20 % of women
at lowest risk.
Insight™Dx Mammostrat™ (Clarient Inc/GE Healthcare) This has been clini-
cally validated as a prognostic test for women with early-stage, hormone-receptor-
positive breast cancer. It combines three traditional pathology staging risk
factors − tumor size, tumor grade, and lymph node status − with seven key molecular
biomarkers, which include ER, PR, HER2, EGFR, BCL2, p53, and MYC. The
information is then combined with a proprietary algorithm to produce a risk score
that assists pathologists and oncologists in clinical decision-making. Clarient con-
ducted an independent study using a set of breast cancer patients from the Royal
Perth Hospital in Western Australia to clinically validate the Clarient Insight
Mammostrat™. The algorithm demonstrated an accurate, actionable risk recurrence
score. In the study, high- and low-risk patients were identifi ed using the Clarient
Insight Mammostrat™. The low-risk group had only a 3 % recurrence rate 10 years
after surgery. This is equivalent to a negative predictive value of about 97 %, and the
corresponding positive predictive value was 39 %. Further details can be seen on the
following web site: http://www.clarientinc.com/mammostrat-overview.aspx.
TaqMan Non-coding RNA Assays (Life Technologies) These assays have helped
to uncover regulatory roles of non-coding RNAs in breast cancer. Long intervening
non-coding RNAs (lincRNAs) in the HOX loci become systematically dysregulated
during breast cancer progression. The lincRNA termed HOTAIR is increased in
expression in primary breast tumors and metastases, and HOTAIR expression level
in primary tumors is a powerful predictor of eventual metastasis and death (Gupta
et al. 2010 ). Enforced expression of HOTAIR in epithelial cancer cells induced
genome-wide re-targeting of Polycomb repressive complex 2 (PRC2) to an occu-
pancy pattern more resembling embryonic fi broblasts, leading to altered histone H3
lysine 27 methylation, gene expression, and increased cancer invasiveness and
metastasis in a manner dependent on PRC2. Conversely, loss of HOTAIR can inhibit
cancer invasiveness, particularly in cells that possess excessive PRC2 activity.
TaqMan non-coding RNA assays can accurately measure expression levels of this
molecular biomarker in different breast cancer samples.
MetaStat™ Breast Cancer Test Scientists at MetaStat Inc have discovered the
micro-anatomical site in breast cancer by direct visual observation, the MetaSite,
the window in the blood vessels through which the metastatic cells squeeze through
10 Personalized Therapy of Cancer