Cancer Chemotherapy

Question 1

what are the two causes of cancer

Answer 1

mutations in DNA resulting in production of altered cells which have changes in proliferating mechanisms

changes in dna caused by covalent modification

• spontaneous or genetic predisposition
• ionising radiation or UV radiation
• chemical carcinogens

Question 2

3 main approaches to dealing with established cancers

Answer 2

• 1) Surgical excision
• 2) Radiotherapy
• 3) Chemotherapy

Question 3

Four types of traditional agent

Answer 3

• Alkylatingagents
• Antimetabolites
• Cytotoxic antibiotics
• Plantderivatives

Question 4

1. Alkylating agents

Answer 4

properties of forming covalent bonds with suitable nucleophilic substances in the cell under physiological conditions, they do this by intrastrand cross linking of DNA
this is normally in the guanine residue ending with thymine not cytosine

Question 5

what are the 6 groups of alkylating agents

Answer 5

1) nitrogen mustards
2) Ethylenimines
3) alkylsulphionates
4) hydrazine and Triazines
5) nitrosoureas
6) platinum based compounds

Question 6

Main drawbacks of chemotherapy of cancer

Answer 6

• Target cell proliferation not the more lethal properties of invasiveness and metastasis
• Non-specific cell killers rather than being aimed at the particular changes which make a cell malignant
• The development of resistance (particularly multidrug resistance) to anticancer drugs
• Leaves some remaining cells