A new class of cancer drugs -- topoisomerase
inhibitors -- is now in use in the United States for treating certain cancers.
The researchers looked at how cancer cells reacted when given PARP inhibitors alongside a type of chemotherapy called topoisomerase
A new high-throughput assay, developed recently in the laboratory of Prof Tony Maxwell of the John Innes Centre (and co-founder of Inspiralis), will also provide a huge advance on the standard gel-based screening method for topoisomerase
Fluorescence spectroscopy studies of vaccinia type IB DNA topoisomerase
. Closing of the enzyme clamp is faster than DNA cleavage.
"The finding that PARP inhibitors improve the anti-cancer activity of Topoisomerase
1 poisons indicates they may be useful in the treatment of bowel cancer.
II(alpha) amplification and anthracycline-based chemotherapy: the jury is still out.
Specific examples are topoisomerases
that belong to the nuclear DNA replication and RNA transcription machinery, where they are key components in DNA-RNA synthesis.
HER-2 amplification and topoisomerase
IIalpha gene aberrations as predictive markers in node-positive breast cancer patients randomly treated either with an anthracycline-based therapy or with cyclophosphamide, methotrexate, and 5-fluorouracil.
Glaxo's new compound latches onto topoisomerase
, which helps bacteria produce proteins and replicate.
PASS prediction of topoisomerase
I inhibitor activity Molecules Pass activity Pass inactivity (Topoisomerase
I inhibitory) inhibitory) A Camptothecin 0.952 0.001 B Irinotecan 0.781 0.002 C Topotecan 0.846 0.002 D 10-Hydroxycamptothecin 0.948 0.001 E 9-Nitrocamptothecin 0.858 0.002 Table 3.
II: Studies have found that tumors with higher levels of topoisomerase
II (topo-II) were more responsive to anthracyclines, but the reverse was also true, where tumors with topo-II deletion also had a high response.
Substitution of conserved residues within the active site alters the cleavage religation equilibrium of DNA topoisomerase