Which chemotherapy drugs are topoisomerase inhibitors?

Topoisomerase I inhibitors include irinotecan, topotecan, and camptothecin, and topoisomerase II inhibitors include etoposide, doxorubicin, and epirubicin.

Are topoisomerase inhibitors cell cycle specific?

Alright, now topoisomerase inhibitors are cell cycle-specific, or CCS, agents, and they are the most active during the late S and early G2 phases of the cell cycle.

How do topoisomerase inhibitors affect cancer cells?

Topoisomerase inhibitors (TI) can inhibit cell proliferation by preventing DNA replication, stimulating DNA damage and inducing cell cycle arrest. Although these agents have been commonly used in the chemotherapy for the anti-proliferative effect, their impacts on the metastasis of cancer cells remain obscure.

Is etoposide topoisomerase inhibitor?

Etoposide was the first agent recognised as a topoisomerase II inhibiting anticancer drug. Research on etoposide has helped the understanding of mechanisms by which drugs poison topoisomerase II.

What are topoisomerase 1 inhibitors?

Topoisomerase I inhibitors are a new class of anticancer agents with a mechanism of action aimed at interrupting DNA replication in cancer cells, the result of which is cell death. Most if not all Topoisomerase I inhibitors are derivatives of the plant extract camptothecin.

Is topoisomerase a chemotherapy?

Topoisomerase inhibitors are chemotherapy drugs used to kill lung cancer (malignant) cells. Topoisomerase inhibitors block the enzymes that break and reconnect DNA strands (topoisomerases) that are needed for cell division and growth.

When is topoisomerase used?

Topoisomerase I helps with replication fork movement and relaxes supercoils associated with transcription. It is also used for relaxing solenoidal supercoils that form when chromosomes condense in preparation for mitosis.

How does etoposide inhibit topoisomerase?

Etoposide kills cells by stabilizing a covalent enzyme-cleaved DNA complex (known as the cleavage complex) that is a transient intermediate in the catalytic cycle of topoisomerase II.

What are topoisomerase II inhibitors?

A substance that blocks the activity of the enzyme topoisomerase II, which cuts and repairs tangled strands of DNA. Topoisomerase II is involved in cell division and growth, so blocking activity of this enzyme may kill cancer cells. Some topoisomerase II inhibitors are being used to treat cancer.

What is the main function of topoisomerase?

Topoisomerases catalyze and guide the unknotting or unlinking of DNA by creating transient breaks in the DNA using a conserved tyrosine as the catalytic residue. The insertion of (viral) DNA into chromosomes and other forms of recombination can also require the action of topoisomerases.

What is the purpose of topoisomerase?

Topoisomerases serve to maintain both the transcription and replication of DNA. Aside from topoisomerases I and II, there are more discovered topoisomerases. Topoisomerase III may regulate recombination while topoisomerase IV regulates the process of segregating newly replicated chromosomes from one another.