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VeraTag™ Assay System for Cancer Biomarkers
The VeraTag™ assay system (Monogram Biosciences) is a high performance, high
throughput system for studies of gene expression, protein expression and for appli-
cations such as cell signaling and pathway activation, protein-protein interaction
and cell receptor binding. The system uses proprietary VeraTag™ reporters to mul-
tiplex the analysis of genes and/or proteins from the same sample. The VeraTag™
assay system is ideally suited to analysis of complex biology such as that seen in
cancer. These unique assays can precisely measure many types of pathway bio-
markers simultaneously − using small samples, such as those obtained from stan-
dard tumor biopsies. These biomarkers could be used to correlate disease type and
progression, resulting in improved treatment. Novel VeraTag™ assays for unique
protein biomarkers such as receptor-complexes and phosphorylation events are
being developed to focus on profi ling Epidermal Growth Factor Receptor (EGFR)
family signal transduction pathways. Further research will be aimed at applying
VeraTag™ assays to retrospective analysis of patient samples from clinical trials for
validation and diagnostic development. It can accelerate the development of tar-
geted therapeutics, improve clinical trial design and results, clarify and individual-
ize the selection of medications, and optimize outcomes for patients with cancer. It
can be used for developing companion diagnostics to guide selection of patients for
HER-targeted therapies.
Determination of Response to Therapy
Several approaches have been investigated for predicting and monitoring response
to anticancer chemotherapy. Some of these are described here.
to Anticancer Therapeutics.................................................................... Biomarker-Based Assays for Predicting Response
to Anticancer Therapeutics
The high incidence of resistance to DNA-damaging chemotherapeutic drugs and
severe side effects of chemotherapy have led to a search for biomarkers able to pre-
dict which patients are most likely to respond to therapy.
ERCC1-XPF nuclease is required for nucleotide excision repair of DNA damage
by cisplatin and related drugs, which are widely used in the treatment of cancer. The
levels of ERCC1-XPF in a tumor could indicate whether it will be sensitive or resis-
tant to a certain chemotherapeutic agent. Although several commercially available
antibodies are suitable for immunodetection of ERCC1-XPF in some applications,
only a select subset is appropriate for detection of this repair complex in fi xed
specimens. A study provides reliable tools for clinicians to measure the enzyme
Determination of Response to Therapy