Why are microtubule-targeting drugs particularly effective against cancer cells?

Microtubule-targeting drugs are particularly effective against cancer cells primarily because they selectively affect fast-dividing cells, which is a characteristic feature of many cancer types. Cancer cells typically have a higher mitotic index than normal cells, meaning they are dividing more frequently. These drugs, such as taxanes and vinca alkaloids, disrupt the normal function of microtubules, which are essential for various processes during cell division, including spindle formation and chromosome segregation.

By targeting microtubules, these drugs induce mitotic arrest in proliferating cells, leading to cell death. Since cancer cells are often continuously dividing at a rapid pace, they are more susceptible to the effects of microtubule disruption compared to normal cells, which divide at a slower and more regulated rate. This selective toxicity towards rapidly dividing cells is what makes microtubule-targeting drugs a key approach in cancer treatment.