Cancer: Targeted Biological Therapy Flashcards
What is the limitation of conventional cytotoxic chemotherapy?
Toxicitiy to normal cells
Lack of individualisation and specificity to patient’s specific tumour characteristics
Lack of effectiveness
What are the classifications of breast cancer?
ER positive/negative
PR positive/negative
HER2 positive/negative
What is HER2?
Human Epidermal growth factor Receptor 2, a tyrosine kinase oncogene that promotes cellular proliferation and can become mutated in breast cancer, due to an issue with the ERRB2 gene.
What is a triple negative breast cancer?
Negative for ER or PR receptors and no abnormality in HER2. Caused by mutation of BRCA1
pIK3/AKT Pathway
Phosphoinotiside 3-kinase pathway which controls apoptosis, cell proliferation. This is regulated by pten protein.
What is GATA-3?
Transcription factor which is responsible for oestrogen receptor expression anddifferentiation. Mutation leads to uncontrolled cell division and metastasis.
What are the features of breast cancer?
Derived from epithelium lining the ducts or tubules, classified as ductal or lobilar breast carcinoma.
What is a ductal carcinoma?
Earliest form of breast cancer which is most common and found in the milk duct lining. They can progress to become invasive if they break off and spread into surrounding tissue.
What is an ER positive cancer?
Tumour growth is driven by high oestrogen levels that are highly expressed. It is the most common cause of breast cancers that leads to luminal carcinomas, and has a better prognosis which is more common in white women.
What is an ER negative cancer?
Tumour expresses very few oestrogen receptors
What is a PR positive cancer?
Tumour which expresses progesterone receptors and drives its growth. It is a hormone positive cancer.
What is a HER2 positive cancer?
Tumours which have overexpression of the protooncogene human epidermal growth factor. Metastasis occurs more, grows faster and spreads and recurs more often and a worse prognosis. It can be treated with HER2 inhibitors.
How does HER act?
Human epidermal growth factor receptor with no ligand and once activated, induce tyrosine kinase and PKC for cell proliferation and differentiation. Expressed in many organs and is a fast spreading cancer that typically targets the bone and lungs.
What is a triple negative breast cancer?
Most common cause of breast cancer in younger women below 40 and causes basal-like carcinomas with the worst prognosis and higher chance of metastasis and recurrence.
It is ER, HER2 negative and PR negative and more common in African women.
This typically occurs due to a mutation in the BRCA1 gene for double strand DNA repair.
How is breast cancer treated?
Chemotherapeutic agent paclitaxel and tamoxifen.
What are the classes of cancer therapies?
Classed based on their target:
Cell cycle signalling
Immune checkpoint inhibitors
Epigenetic modifiers
Angiogenesis
How do targeted therapies work?
Acts on specific molecular targets associated with cancer designed to interact with target which are cytostatic (block cancer cell growth).
What are the cell signalling therapies?
Control of cell cycle progression and ligands involved such as EGFR.
What is CDK2?
Cyclin-dependent kinase 2 which is a cell cycle inhibitor that controls rate of cell proliferation for G1->S phase.
What are the D type cyclins?
Cell cycle components which increase progression through G1.