Biomarker Signatures and Clinical Tests

Vocabulary flashcards covering the identification, validation, and clinical application of biomarker signatures, specifically Oncotype DX and PredictSure-IBD.

Biomarker Signature

A combination of multiple biomarkers used to increase predictive power compared to an individual biomarker.

Microarray analysis

A method used for the identification of biomarkers by analyzing mRNA expression levels or gene variations between controlled and experimental groups.

Data quality control

The use of statistical analysis to identify genes that are under-expressed or over-expressed between two groups.

Correlation analysis

Analysis performed to identify the association of a biomarker signature with a phenotype, such as a disease subtype, drug response, or prognosis.

Clinical validation

The process of repeating an analysis in a different patient population to determine if the relationship observed in the training data is maintained.

Clinical utility

The assessment of a validated biomarker signature's usefulness in clinical practice.

Oncotype DX Breast Cancer Test

A test for patients with early hormone positive, HER-2 negative, lymph node negative breast cancer used to guide cytotoxic chemotherapy decisions by predicting 10-year risk of recurrence.

Oncotype DX Gene Panel

A signature of $21$ genes identified from $447$ patients, consisting of $16$ breast cancer-related genes and $5$ reference genes.

Recurrence Score (Oncotype DX)

A value calculated from mRNA expression levels normalized against reference genes, where each gene is scored from $0$ to $15$ and a $1$ unit increase represents a doubling of mRNA.

Quantitative RT-PCR assay

The assay format used to determine the mRNA expression levels for the Oncotype DX and PredictSure-IBD biomarker signatures.

PredictSure-IBD

A biomarker signature consisting of $17$ genes ($15$ IBD-related genes and $2$ reference genes) identified from $39$ candidate genes.