Chemotherapy primarily targets the actively dividing phase of the cell cycle, known as the DNA synthesis (S) phase and the cell division (M) phase. By interfering with cell division, chemotherapy drugs aim to inhibit the growth of cancer cells.
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Chemotherapy primarily targets the actively dividing phase of the cell cycle, known as the DNA synthesis (S) phase and the cell division (M) phase. This is because during these phases, cells are more vulnerable and sensitive to the effects of chemotherapy drugs. By interfering with cell division, chemotherapy drugs aim to inhibit the growth of cancer cells.
One interesting fact is that chemotherapy drugs can be classified into different categories based on their mechanisms of action and the specific phases of the cell cycle they target. For example, antimetabolites such as methotrexate and 5-fluorouracil disrupt the DNA synthesis (S) phase, while mitotic inhibitors like paclitaxel and vinblastine disrupt the cell division (M) phase.
Another interesting fact is that chemotherapy drugs can have different impacts on normal cells versus cancer cells during the cell cycle. Normal cells have various mechanisms in place to repair DNA damage and maintain cell cycle checkpoints, which can help protect them from the effects of chemotherapy drugs. In contrast, cancer cells often have defects in these mechanisms, making them more susceptible to the drugs.
One famous quote related to chemotherapy and its targeting of the cell cycle is by the Nobel laureate Albert Szent-Györgyi: “Cancer is a disease of civilization. Our cells were designed to live long, full lives, but exposure to toxins, poor nutrition, and genetic factors can disrupt the delicate balance of our cell cycles. Chemotherapy is our way of intervening, attempting to restore order to the chaos.”
Here is a table illustrating some chemotherapy drugs and the specific phases of the cell cycle they target:
| Chemotherapy Drug | Cell Cycle Phase Targeted |
|---|---|
| Methotrexate | DNA Synthesis (S) Phase |
| 5-fluorouracil | DNA Synthesis (S) Phase |
| Paclitaxel | Cell Division (M) Phase |
| Vinblastine | Cell Division (M) Phase |
| Doxorubicin | Various phases, DNA damage |
| Cisplatin | Various phases, DNA damage |
Please note that this information is for illustrative purposes only and may not include all chemotherapy drugs or their specific targets. It is always important to consult medical professionals for accurate and up-to-date information regarding chemotherapy and its effects on the cell cycle.
Video answer to “What part of the cell cycle does chemotherapy target?”
The video titled “Pharmacology – Chemotherapy agents (MOA, Alkalating, antimetabolites, topoisomerase, antimitotic)” provides a comprehensive overview of different classes of chemotherapy agents and their mechanisms of action. It explains that alkylating agents form cross-linkages with DNA, preventing replication and cell division. Antimetabolites disrupt DNA and RNA metabolism, while anti-tumor antibiotics inhibit topoisomerase, leading to inhibited cell growth. Antibiotics can also induce reactive oxygen species formation for cell destruction and apoptosis. The video also mentions the role of topoisomerase inhibitors in DNA replication and the impact of anti-microtubule agents on the M phase of the cell cycle. It’s worth noting that hormonal agents are not discussed in this particular video.
Here are some more answers to your question
DNA replication
All dividing cells must go through the process of DNA replication. Since cancer cells are often rapidly dividing, this phase of the cell cycle is the target of many of the chemotherapy agents that will be described in the ‘Cancer Treatments’ section.