Hormonal Antitumor Drugs & Targeted Antitumor Drugs
Hormonal antitumor drugs inhibit the action or production of hormones that stimulate the growth of certain cancers. These are particularly useful for hormone-sensitive tumors such as breast, prostate, and endometrial cancers.
Classification
- 1. Anti-Estrogens:
- Tamoxifen
- Raloxifene
- 2. Aromatase Inhibitors:aroma
- Anastrozole
- 3. Anti-Androgens:
- Flutamide
- 4. GnRH Agonists/Antagonists:
- Leuprolide
- 5. Progestins:
- Medroxyprogesterone acetate
Pharmacodynamics
- Anti-Estrogens: Block estrogen receptors → inhibit estrogen-stimulated cancer cell proliferation. Example: Tamoxifen (selective estrogen receptor modulator, SERM)
- Aromatase Inhibitors:
Inhibit aromatase enzyme → ↓ peripheral estrogen synthesis → ↓ tumor growth in estrogen-dependent tumors. Example: Anastrozole
- Anti-Androgens: Block androgen receptors → prevent testosterone/DHT from promoting prostate cancer cell growth. Example: Flutamide
- GnRH Agonists/Antagonists: Initially increase, then suppress LH/FSH → ↓ estrogen/testosterone production → inhibit hormone-driven tumor growth. Example: Leuprolide
- Progestins: Mimic progesterone → ↓ estrogen receptor expression + direct antiproliferative effects. Example: Medroxyprogesterone acetate
Side Effects
- Common:
- Hot flashes
- Fatigue
- Nausea
- Joint pain
- Weight gain
- Mood swings, ↓ libido
- Serious/Rare:
- Thromboembolism (esp. with tamoxifen)
- Osteoporosis (aromatase inhibitors, GnRH analogs)
- Endometrial cancer (tamoxifen)
- Cardiovascular events
- Interstitial lung disease
- Hepatotoxicity