Hormonal Drugs

Question 1

long-acting GnRH analogs (eg, goserelin)

Answer 1

• continuous GnRH stimulation by long-acting GnRH analogs suppresses LH and FSH release, decreasing production of estrogens in the ovarian follicle.
• useful for ovarian suppression in premenopausal women with ER-positive breast cancer.
• Pulsatile stimulation of the pituitary by gonadotropin-releasing hormone (GnRH) increases secretion of LH and FSH.

Question 2

Tamoxifen

Answer 2

• . acts as either an antagonist or a partial agonist of the estrogen receptor, depending on the tissue.
• In breast tissue, tamoxifen antagonizes the estrogen receptor and can be used as adjuvant therapy for ER-positive breast cancer.

Question 3

Trastuzumab

Answer 3

• monoclonal antibody against HER2 that is used in patients with HER2-positive tumors
• inhibits MAPK and PI3K/Akt signaling pathways, increases degradation of HER2, and facilitates antibody-mediated destruction of tumor cells.

Question 4

5-α reductase inhibitors (eg, finasteride)

Answer 4

inhibit the action of androgens on the prostate gland, preventing the conversion of testosterone to dihydrotestosterone and thereby limiting further prostate enlargement