Chemotherapy Drugs Flashcards Preview

Year 2 Pharmacology > Chemotherapy Drugs > Flashcards

Flashcards in Chemotherapy Drugs Deck (29):
1

Inherited cause of cancer?

Defective BRCA1/2 genes in breast cancer; deficiency in DNA repair enzymes

2

Acquired cause of cancer?

Viruses, carcinogens (asbestos, smoking, radiation) alcohol, drugs, sun, geographical location

3

Proto-oncogenes

Normal genes which can mutate to become oncogenes Potential to cause cancer

4

Metastasis, location of secondary tumour

1. primary tumour 2. invades near by tissue 3. grows new blood vessels (angiogenesis) 4. secondary tumour

5

Objectives of cancer therapy

1. curing patient - eliminating all traces of cancer
2. prolonging life - shrinking tumours
3. palliative therapy - improving Qol, reducing pain

6

Difficulties in treating cancer?

-asymptomatic, until late symptoms
-detection methods are not 100% reliable
-hard to find primary site
-cancer cell similar to normal cells
-difficulties to exploit biochemical differences

7

Aims of chemo

to kill all malignant cells in body

8

Toxic effects of chemotherapy

-bone marrow suppression
-impaired wound healing
-loss of hair -damage to GI epithelium
-growth stunted
-reproductive system > sterility
-teratogenicity -bleeding and bruising
-N+V -kidney damage

9

Classes of anti cancer drugs

1. cytotoxic (alkylating, antimetabolites, antibiotics , plant derivatives ) = block DNA synthesis/ prevent cell division 2.hormones (+ their antagonist) = supress opposing hormone secretion or inhibit their actions
3.monoclonal antibodies = target specific cancer cells 4.protein kinase inhibitors = block cell signally pathways in rapidly dividing cells

10

What are the different classes of alkylating agents? (cytotoxic drugs)

Nitrogen mustards -cyclophopshamide
Nitrosoureas -lomustine CCNU, carmustine BCNU Platinum compounds -cisplatin, carboplatin
Busulphan

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Have cytotoxic effects in rapidly growing cells - very reactive given IV
Mechlorethamine **
Cyclophosphamine

Melphalan
Chlormbucal
Bendamustine
Estraustine

examples of nitrogen mustards

12

Nitrogen mustards : Cyclophosphamide

Prodrug - can be administered orally
Activated in the liver to phosphoramide mustard + acrolein Acrolein = haemorrhagic cystitis
Can cause cystitis

13

What are the different classes of antimetabolites? (cytotoxic drugs)

Folate antagonists - methotrexate
Pyrimidine analogues - fluorouracil
Purine analogues - fludarabine

14

What are examples of cytotoxic antibiotics? (cytotoxic drugs)

doxorubicin
bleomycin

15

What are example of plant derivatives? (cytotoxic drugs)

vincristine
vinblastine
vindesine

16

Glucocorticoids - prednisolone, dexamethasone Oestrogens - diethlstilbestrol
Progestogens - megesterol
Gonadotropin-releasing hormone analogues - goserelin Antioestrogens - tamoxifen
Antiandrogens - flutamide

Different classes of hormones

17

How do cytotoxic drugs work?

Block DNA synthesis/ prevent cell division

18

How do hormones (and their antagonists) work?

They supress opposing hormone secretion or inhibit their actions

19

How do monoclonal antibodies work?

Target specific cancer cells

20

How do protein kinase inhibitors work?

block signalling pathways in rapidly dividing cells

21

How do alkylating agents work?

target cells in DNA synthesis phase (S phase)
form covalent bonds with DNA to prevent uncoiling
SIDE EFFECTS
sterility increased risk of non-lymphatic leukaemia

22

Highly lipophilic - cross the BBB to treat CNS tumours. Carmustine IV - multiple myeloma, non-Hodgkin's lymphoma and brain tumours
Lomustine oral - Hodgkin's disease, malignant melanoma and certain solid tumours

example of Nitrosoureas

23

What are platinum compounds (alkylating agents)

eg Cisplatin Potent alkylator -
binds to RNA > DNA > protein
Binds to purine bases (G,A,U)
Resistance may develop - DNA repair by DNA polymerase SIDE EFFECTS
very nephrotoxic (requires hydration), severe N+V, risk of tinnitus, peripheral neuropathy, hyperuriceamia (gout), and anaphylaxis

24

Other platinum compounds

Carboplatin
derivative of cisplatin (ovarian and lung cancer)
Less side effects
Oxaliplatin
used to treat colorectal cancer (with fluorouracil and folinic acid)
Side effects bone marrow suppression (myelotoxic)

25

What other alkylating agents are there?

Busulfan - selective for bone marrow, leukaemia treatment 
Procarbazine - Hodgkins disease but cause hypersensitivity rash and inhibits MAOIs
Trabecteolin - soft tissue sarcoma/advanced ovarian cancer but is hepatotoxic

26

What are Folate antagonists (antimetabolites, cytotoxic drugs)

-essential for DNA synthesis/cell division
e.g Methotrexate
- inhibits dihydrofolate reductase
-given orally, i.m , i.v or intrathecally
-low lipid soluility

27

Explain Pyriminidine Analogues (antimetablites, cytotoxic drugs)

Complete with C and T bases which make up DNA and RNA
Flurouracil (soild tumours, GI camcers and breast)
Capecitaine (colon/colorectal cancer, breast cancer)
Cytarabine (acute myeloblastic leukaemia)
Gemcitabine (pancreatic/bladder/ovarian/breast)
 

28

Explain Purine analogues (antimetablites, cytotoxic drugs)

Complete with A and C - inhibit purine metabolism
Mercaptopurine
Tiogunanine
Pentostatin
Fludaraine

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