Classification of Anticancer Drugs

Anticancer drugs, also known as antineoplastic agents, are classified based on their mechanism of action. Here’s a breakdown of the main categories:

1. Alkylating Agents

These drugs work by adding alkyl groups to DNA, which prevents cancer cells from replicating and leads to cell death.

• Examples: Cyclophosphamide, Ifosfamide, Melphalan, Cisplatin

2. Antimetabolites

These drugs interfere with DNA and RNA synthesis by mimicking natural substances (e.g., nucleotides). They block the growth of cancer cells.

• Examples: Methotrexate, 5-Fluorouracil (5-FU), Cytarabine, Gemcitabine

3. Antitumor Antibiotics

These antibiotics bind to DNA and inhibit its replication or transcription, thereby stopping cancer cell growth.

• Examples: Doxorubicin, Daunorubicin, Bleomycin, Mitomycin C

4. Plant Alkaloids (Mitotic Inhibitors)

These agents inhibit cell division by disrupting the formation of microtubules, essential for mitosis.

• Examples:
  • Vinca Alkaloids: Vincristine, Vinblastine
  • Taxanes: Paclitaxel, Docetaxel
  • Podophyllotoxins: Etoposide, Teniposide

5. Topoisomerase Inhibitors

These drugs inhibit topoisomerase enzymes, which are involved in DNA replication and repair, causing DNA breaks in cancer cells.

• Examples: Irinotecan, Topotecan, Etoposide

6. Hormonal Agents

These drugs affect hormone-sensitive cancers by either inhibiting or mimicking hormones, thereby blocking cancer growth.

• Examples:
  • Anti-estrogens: Tamoxifen, Letrozole
  • Anti-androgens: Flutamide, Bicalutamide

7. Targeted Therapies

These drugs specifically target molecular pathways essential for cancer cell growth and survival, sparing normal cells.

• Examples:
  • Tyrosine Kinase Inhibitors (TKIs): Imatinib, Erlotinib
  • Monoclonal Antibodies: Trastuzumab, Rituximab

8. Immunotherapy

These therapies boost the immune system to recognize and attack cancer cells.

• Examples: Pembrolizumab, Nivolumab, Ipilimumab

9. Differentiating Agents

These agents cause cancer cells to mature into normal cells, halting their abnormal growth.

• Examples: All-trans Retinoic Acid (ATRA), Arsenic Trioxide

10. Proteasome Inhibitors

These drugs block proteasomes, leading to the accumulation of proteins that cause cell death in cancer cells.

• Examples: Bortezomib, Carfilzomib

Each of these drug classes is used based on the type of cancer and its specific molecular or cellular characteristics.