Several mechanisms contribute to drug inactivation in cancer:
Enzymatic Degradation: Certain enzymes within cancer cells can metabolize and deactivate drugs. For example, the enzyme cytochrome P450 can metabolize chemotherapy agents. Drug Efflux Pumps: These are proteins that actively pump drugs out of cancer cells, reducing intracellular drug concentrations. P-glycoprotein is a well-known efflux pump associated with multi-drug resistance. Gene Mutations: Mutations in genes encoding drug targets can alter the binding affinity of the drug, rendering it ineffective. Altered Drug Targets: Changes in the structure or expression levels of drug targets can also lead to inactivation.
