Biomarkers in Cancer Practice Flashcards

This set covers vocabulary related to cancer biomarkers, including types, roles, genetic testing methods, and specific protein/gene examples discussed in the lecture.

Biomarkers

A gene, protein, imaging result or a clinical measure that indicates a normal biological process, pathogenic process or pharmacological response to a therapeutic intervention.

Diagnostic biomarker

A type of biomarker that helps with the diagnosis of a disease.

Predictive biomarker

A type of biomarker that helps with prediction of treatment efficacy and diagnosis.

Metabolic biomarker

A type of biomarker that helps with the identification of metabolism pathways.

Outcome biomarkers

Biomarkers that help determine treatment outcomes or disease outcomes.

Prognosis biomarkers

Genetic or protein biomarkers that indicate the quality of tumours, such as if they are aggressive or metastatic, or how they respond to treatments.

Circulating biomarkers

Molecules released by cancer cells or tumours into the blood which are measured via a blood sample.

Tumour tissue markers

Markers used to see genetic sequences within cancer cells or the expression of proteins in tumours; measurement usually requires a biopsy or surgical removal of tissue.

Genomics

The study of identifying biomarkers by measuring the genes or $DNA$ present.

Transcriptomics

The study of identifying biomarkers by determining which genes are expressed.

Proteomics

The study of identifying biomarkers by looking at the levels of proteins in cells.

Metabolomics

The study of identifying biomarkers by looking at molecules or metabolised substances released in or by cells.

Predictive Genetic Tests

Tests that reveal the risk of developing cancer based on gene variants, though they indicate risk rather than certainty.

BRCA1 and BRCA2

$\text{BReast CAncer susceptibility gene 1 and 2}$; these genes play a role in repairing $DNA$ double-strand breaks.

Positive Sequence Result

A finding where a patient's sequence contains a harmful variant known to increase cancer risk.

Negative Sequence Result

A finding where a patient's sequence does not contain a known pathogenic variant.

Variant of unknown significance

A finding where a sequence contains an uncommon variant not yet associated with cancer, which does not rule out the risk of developing the disease.

FIT (Faecal Immunochemical Test)

A screening test that detects blood in faecal samples using specific antibodies that bind to $Hb$, providing high sensitivity for colon cancer indication.

$V600E$ $BRAF$ mutation

A common mutation in colorectal cancer where the $BRAF$ protein becomes constitutively active, leading to unregulated cell growth and proliferation.

Oncotype DX

A genetic test that measures the expression of a $21$ gene panel ($16$ cancer-related and $5$ reference genes) in breast cancer to predict recurrence risk and chemotherapy benefits.

HER2

A tyrosine kinase growth receptor involved with cell growth and division that is overexpressed in 20\text{-}30$\% of breast cancers.

Trastuzumab

A monoclonal antibody biologic that binds to the extracellular domain of $HER2$ receptors to block growth signals.

Gefitinib

A tyrosine kinase inhibitor used to treat $NSCLC$ by binding to the $ATP$ binding site in the catalytic domain to block growth.

NSCLC

$\text{Non-small-cell lung cancer}$; a condition where $EGFR$ is often overexpressed in 40\text{-}80$\% of cases.

KIT

A tyrosine kinase receptor often mutated in $GIST$ ($\text{gastrointestinal stromal tumours}$), leading to uncontrolled growth.

Imatinib

The first anti-$KIT$ tyrosine kinase inhibitor; patients with variants in exon $11$ typically respond better than those with exon $9$ mutations.

Mercaptopurine

A drug used for acute and chronic myeloid leukaemia that inhibits purine metabolism and $DNA$ synthesis; it is metabolised by $TPMT$.

TPMT

$\text{Thiopurine Methyltransferase}$; an enzyme that metabolises Mercaptopurine. Mutations in this enzyme can lead to cytotoxicity and myelosuppression.

CEA (Carcinoembryonic Antigen)

A glycoprotein circulating protein biomarker used to measure plasma levels to monitor treatment response and recurrence in cancers like bowel cancer.

VEGF

A factor important for angiogenesis and the growth of blood vessels; targeted by inhibitors such as Bevacizumab.

Tie2

An Angiopoietin Receptor required for vascular stability. High plasma levels of this protein are linked to a good response to Bevacizumab in ovarian and colorectal cancer.