Question

A mitosis inhibitor is a medication that is designed to prevent mitosis in certain cells. Why would these inhibitors be helpful in the treatment of tumors?

1) Tumors grow more slowly than normal cells
2) Tumors do not normally undergo mitosis
3) Tumors cannot normally duplicate
4) Tumors grow when cell cycle errors cause uncontrolled cell division

Answer 1

Mitosis inhibitors such as vincristine and colchicine disrupt tumor growth by preventing proper spindle formation during mitosis, thereby interfering with cell division and potentially leading to cancer treatment effectiveness.

Step-by-step explanation:

Mitosis inhibitors are beneficial in the treatment of tumors because they can interfere with the uncontrolled cell division that characterizes tumor growth. Specifically, these inhibitors work by restricting the separation of chromosomes or interfering with the assembly and disassembly of microtubules, which are essential in the formation of spindle fibers during mitosis.

For example, chemotherapy drugs like vincristine and colchicine bind to tubulin, preventing the proper formation of spindles, thus disrupting cell division. Without these structures, a cell cannot correctly distribute its chromosomes during cell division, leading to cell death or the inhibition of cell proliferation.

This mechanism is especially relevant to cancer cells as they rapidly and continuously divide, and by inhibiting this process, mitosis inhibitors can effectively slow down or halt the progression of the cancer.