lecture 20 - targeted cancer therapies

Question 1

cancer

Answer 1

disease of cell populations that divide, invade and spread without regard to normal limits

molecular basis = abnormalities in DNA (by carcinogens, DNA replication errors, inherited)

cells acquire a series of common key phenotypic characteristics:
• evading apoptosis
• self-sufficiency in growth signals
• insensitivity to anti-growth signals
• ability to invade tissues and metastasis
• limitless replicating potential
• sustained angiogenesis

Question 2

pathophysiological basis of cancer

Answer 2

• growth and evasion of primary tumour
• metastasis and distant effects of wide-spread disease
• systemic effects of para-neoplastic syndromes

Question 3

chemotherapy targeting cycling cells

Answer 3

• targets cycling cells without discrimination
• selective toxicity achieve due to higher numbers of dividing cells in tumour
• adverse effects due to inhibition of proliferation of normal cells

Question 4

anti-microtubule drugs

Answer 4

• eg. paclitaxel

* inhibits mitotic spindle = M phase specific

Question 5

anti-metabolites

Answer 5

• eg. methotrexate

* inhibits DNA synthesis = S phase specific

Question 6

targeted cancer therapy

Answer 6

drug treatments that inhibit oncoproteins that drive tumour growth

allows individualisation of therapy based on genetic testing

• small molecular drugs (eg. imatinib, gefitinib) target specific enzymes or growth factor receptors
• monoclonal antibodies (eg. trastuzumab, bevacizumab) target growth factors or receptors

Question 7

gefitinib

Answer 7

• small molecular drug inhibits EGFR
• used in the treatment of non-small cell lung cancer
• inhibits tyrosine kinase activity

adverse effects: diarrhoea, rash

Question 8

Sunitinib

Answer 8

• small molecular drug inhibits VEGF
• treatment for renal cell cancer

adverse effects: cardiac failure, hypertension, haemorrhage

Question 9

define targeted cancer therapy

Answer 9

drug treatment that interferes with specific molecules needed for tumour development and/or progression

Question 10

types of targeted cancer therapies

Answer 10

small molecular drugs

• block specifc enzymes or GF receptos
• e.g. gefitinib, imatinib

monoclonal antibodies

• bind to growth factors or their receptors
• e.g. trastuzumab, bevacizumab

Question 11

imatinib

Answer 11

• small molecular drug inhibits tyrosine kinase activity
• treatment for chronic myelogenous leukemia

adverse effects: generally well tolerated