Immunotherapy and Cancer: Harnessing the Power of Diagnostic Assays - 6

Immunotherapy and Cancer | Harnessing the Power of Diagnostic Assays
belong to the largest class of immune-oncology drugs, known as
checkpoint inhibitors (see I-O Drug Classes on page 8).
* MSI, or microsatellite instability, is caused by mutations in mismatch repair genes. MSI is also used as a biomarker to select
patients for treatment with checkpoint inhibitors.
Two emerging biomarkers include:
* TMB, or tumor mutational burden, which measures the amount
of mutations present in tumor cells.
* GEx signatures, or gene expression profiling, which measures the
mRNA expression level of various genes involved in the immune
response.

"There have been great successes using PD-L1 IHC, but there
is room for improvement in terms of finding more patients who
are likely to respond," Spittle says. Despite relative improvements over traditional treatments, she adds, "the response
rate is still pretty low with the one-biomarker approach" for
immunotherapies.
Thankfully, more biomarkers are being discovered to assist researchers and clinicians with patient selection. And, evidence suggests that
a multi-biomarker approach will result in the maximum number of
eligible patients being identified for either approved immunotherapies, or for those moving through clinical trials. "We recognize the

Sequence-based techniques have
provided information on multiple genes
in parallel, but selection of genes and
data analysis requires extensive cause
and effect relationships for
evidence-based diagnostic use.

DNA was the target of the first
molecular diagnostic assays, but is
the furthest from determining
protein regulation which defines
Cellular Function.

PCR
NGS

rt-PCR
rt-qPCR

Real-time quantitative PCR methods
provide single gene analysis, which
have been commonly adopted for
single gene, single drug diagnostic
applications.

A Clinical OMICs eBook

RNA
Microarrays
RNAseq

IHC

Advancements have been made with
new techniques which get closer to the
determination of Protein Regulation
and hence, Cellular Function

www.clinicalomics.com

http://www.clinicalomics.com

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