Chemosensitivity-Resistance Assay as Functional Profiling

Modern cancer research can be divided into three principal disciplines based upon methodology:

1.     Genomic — the analysis of DNA sequences, single nucleotide polymorphisms (SNPs), amplifications and mutations to develop prognostic and, to a limited degree, predictive information on cancer patient outcome.

2.     Proteomic — the study of proteins, largely at the level of phosphoprotein expressions.

3.     Functional — the study of human tumor explants isolated from patients to examine the effects of growth factor withdrawal, signal transduction inhibition and cytotoxic insult on cancer cell viability.

Contrary to analyte-based genomic and proteomic methodologies that yield static measures of gene or protein expression, functional profiling provides a window on the complexity of cellular biology in real-time, gauging tumor cell response to chemotherapies in a laboratory platform. By examining drug induced cell death, functional analyses measure the cumulative result of all of a cell’s mechanisms of resistance and response acting in concert. Thus, functional profiling most closely approximates the cancer phenotype.  Insights gained can determine which drugs, signal transduction inhibitors, or growth factor inhibitors induce programmed cell death in individual patients’ tumors. Functional profiling is the most clinically validated technique available today to predict patient response to drugs and targeted agents.