1. Principles of Chemotherapy: The Stages of Mitosis Mitosis (=cell division) is divided into well-defined stages; the prophase (chromosomes become visible and spindle begins to form); the metaphase (spindle is completed, chromosomes begin to separate); the anaphase (the cell begins to divide in two); and the telophase (the final step of mitosis).
2. Principles of Chemotherapy: Electron Micrograph of Mitotic Cell This is an electron micrograph of a cell from ovarian tissue undergoing mitotic cell division.
3. Principles of Chemotherapy: Classification of Cytotoxic Agents Twenty anticancer agents account for over 95% of all prescriptions in chemotherapy. They are divided into five major classifications.
4. Principles of Chemotherapy: Action Sites of Cytotoxic Agents/Cell Cycle Level Understanding the cell cycle is important because chemnicals with different modes of action may be rationally combined to increase antitumor effects at different times in the cell cycle.
5. Principles of Chemotherapy: Action Sites of Cytotoxic Agents/Cellular Level Most cytotoxic drugs target the DNA. Two exceptions are the poisons of the mitotic spindle—vinca alkaloids and taxoids—that target the tubulin.
6. Principles of Chemotherapy: Action Sites of Cytotoxic Agents Knowledge of the different sites of action for cytotoxic agents permits, for example, the better understanding of how drugs act in combination.
7. Principles of Chemotherapy: Metabolism of Cytotoxic Agents/Cyclophosphamide Presented here is an example of how one cytotoxic agent – cyclophosphamide – is metabolized. Cyclophosphamide is a prodrug. It needs an activation in the body and its metabolites are the active agents.
8. Principles of Chemotherapy: Drug Resistance This phosphoglycoprotein (P.G.P.) is responsible for multidrug resistance. It acts by rejecting the anticancer agent from the cell. Other mechanisms of resistance exist.
9. Principles of Chemotherapy: Aim of Combination Therapy The aim of combination therapy is to increase efficacy while keeping an acceptable safety profile. For example, two drugs in a combination therapy may have different mechanisms of action, and/or limiting drug resistance.
10. Principles of Chemotherapy: Side Effects of Chemotherapy There are multiple side effects of chemotherapy. Some are common, such as alopecia, neutropenia. Some are rare such as cardiotoxicity. The side effects are generally the consequence of the cytotoxic effect of chemotherapy on normal cells, however they can also be related to the direct toxicity of the drug.
