Glossary

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Term Definition
Base excision repair (BER) A process that removes and replaces damaged or misincorporated bases in one strand of the DNA, which if left unrepaired may generate mutations. In base excision repair, the damaged base is modified and excised to create a single-stranded DNA gap that is repaired to regenerate an intact DNA helix.
BRCA mutations “BRCA” is an abbreviation for “BReast CAncer gene.” Mutations in the BRCA1 and BRCA2 tumour suppressor genes can increase the chance of a person developing certain cancers including breast and ovarian cancer.
Cytoreductive surgery Surgery to reduce the number of tumour cells in a patient.
DNA Damage Response (DDR) Cellular mechanisms that identify, signal and correct damage to DNA.
Germline mutation A genetic change in a reproductive cell (egg or sperm) that becomes incorporated into the DNA of every cell in the body of the offspring.
End-resection A vital step in homologous recombination (HR) repair, which generates a long 3’ ssDNA tail that can invade the homologous DNA strand.
HER2 Also known as c-erbB-2 and human epidermal growth factor receptor 2. HER2 is a protein can promote the growth of breast cancer cells and is an important biomarker and target of therapy in some breast cancer patients.
Homologous recombination deficiency (HRD) Homologous recombination (HR) is a type of genetic recombination in which nucleotide sequences are exchanged between two similar (homologous) DNA molecules, which allows repair of double-stranded DNA breaks.
Homologous recombination repair (HRR) The error-free repair of a double-strand break in DNA in which the broken DNA molecule is repaired using homologous DNA sequences.
Immunohistochemistry (IHC) A laboratory technique that uses the principle of antibodies binding to antigens to detect the antigens (e.g.proteins) in cells of a tissue.
Loss of heterozygosity (LOH) A genetic event that leads to the loss of an entire gene and the surrounding chromosomal region. Loss of heterozygosity events are often important steps in tumour progression.
Maintenance treatment Treatment given to eliminate or supress cancer over a prolonged period after initial treatment.
Metastatic castration-resistant prostate cancer (mCRPC) Progression of prostate cancer during androgen deprivation therapy to the castration-resistant state defined by rising prostate specific antigen (PSA) levels and distant metastases.
Mismatch repair A DNA repair pathway that repairs DNA errors that occur during the normal course of DNA replication
Micro-homology mediated end-joining (MMEJ) One of the cellular pathways used to repair double-strand breaks in DNA also known as alternative nonhomologous end-joining (alt-NHEJ), which involves use of small micro-homologous DNA sequences of 2-12 base pairs in length during the alignment of broken DNA ends before joining.
Non-homologous end joining (NHEJ) The repair of a double-strand break in DNA in which the two broken ends are rejoined that are not homologous and have little or no sequence similarity.
Non-metastatic, hormone-sensitive prostate cancer Prostate cancer that has not spread to other parts of the body and still responds to androgen deprivation therapy.
Nucleotide excision repair (NER) DNA repair in which a small region of the strand surrounding the area of DNA damage is removed from the DNA helix as an oligonucleotide. The small gap left in the DNA helix is filled in by the sequential action of DNA polymerase and DNA ligase.
Overall survival (OS) The time from randomisation in a clinical trial to death from any cause.
PSA50 Prostate-specific antigen decline of >50%
PARP Poly(ADP-ribose) polymerase A family of enzymes that catalyse the transfer of ADP-ribose to target proteins, which plays an important role in the intracellular DNA damage response pathways.
PARP-trapping The process by which PARP inhibitors lead to trapping of PARP proteins in DNA.
Platinum-based chemotherapy Chemotherapy that contains the metal platinum, such as cisplatin and carboplatin.
Platinum-sensitivity Cancer that responds to platinum-based chemotherapy.
Progression-free survival (PFS) The time from randomisation in a clinical trial to disease progression or death from any cause.
Registration trials A trial that is the basis for initial regulatory approval of a new drug.
Single strand break (SSB) When one of the two strands of DNA is broken
Small cell lung cancer (SCLC) An aggressive lung cancer which accounts for 10-15% of lung cancers.
Somatic mutation An alteration in DNA that occurs after conception, which can occur in any of the cells in the body except the germ cells (sperm and egg) and therefore are not passed on to offspring.
Time to second progression or death (TTSP) Time from randomisation to objective tumour progression on next-line treatment or death from any cause.
Last update: 25 July 2019