Endocrine Cancers

Question 1

Name 1 drug used for breast cancer

Answer 1

Selective Estrogen Receptor Modulator (SERM)- Tamoxifen

Question 2

MOA of tamoxifen

Answer 2

competitively blocks endogenous estrogen binding to ER in breast → tamoxifen-ER complex alters estrogen-responsive gene expression, thus preventing cell activation and proliferation
Cis isomer exhibits estrogenic activity while trans isomer exhibits anti-estrogenic activity

DDI: grapefruit juice/pomelo, antidepressants, diphenhydramine (cough and cold)

Question 3

Name a drug used in cervical cancer?

Answer 3

Pembrolizumab

Question 4

MOA of Pembrolizumab

Answer 4

Biologic (PD-1i).blocks Programmed cell death protein-1 (PD-1) which binds to PD-1 and release PD-1 pathway-mediated inhibition of T-cell activity

Question 5

ADR of Pembrolizumab

Answer 5

hypersensitivity (rash, itchiness), fatigue, diarrhoea, Nausea, joint pain, (life-threatening) immune-inflammation on lung, endocrine organs, liver, kidney, sepsis

Question 6

Name 2 drugs used in prostate cancer.

Answer 6

1. Leuprorelin (GLP-1 Agonist)
2. Bicalutamide

Question 7

MOA of leuprorelin

Answer 7

GLP-1 Agonist. GnRH analogue acting as an agonist at pituitary GnRH receptor. Decreased androgen production in testes → minimise effect on androgen-sensitive prostate cancer cells → apoptosis

Question 8

ADR of leuprorelin

Answer 8

local pain and redness, hot flushes, headache, GI disturbance, altered mood, hyperglycemia, decreased libido

Question 9

MOA of bicalutamide

Answer 9

Androgen Receptor (AR) antagonist. Competitive inhibitor of AR and inhibits nuclear translocation of AR and interaction of AR with promoter at AR response element → inhibit AR-dependent transcription prevents cell proliferation → apoptosis
inhibit AR → increase LH secretion →(initial negative feedback) higher serum testosterone levels

Question 10

ADR of tamoxifen

Answer 10

Hot flushes, increased risk of endometrial cancer, DVT, menstrual irregularities, vaginal bleeding and discharge (counselling), NV, (high doses) neurotoxicity - tremor, unsteady gait, hyperreflexia, dizziness

Question 11

CI of pembrolizumab

Answer 11

corticosteroids, immunosuppresants, pregnant

Question 12

ADR of Bicalutamide

Answer 12

Competitive inhibitor of AR and inhibits nuclear translocation of AR and interaction of AR with promoter at AR response element → inhibit AR-dependent transcription prevents cell proliferation → apoptosis
inhibit AR → increase LH secretion →(initial negative feedback) higher serum testosterone levels