Purine Analogues Help

[CBsMommy]

Hello all -

Can someone tell me how purine analogues work? I know they replicate purines in DNA. Do they attach to the DNA strand like folic acid antagonists? Do they inactivate the purines in DNA? Is that what kills the cancer cells (because they can't complete metabolism)? There is NOTHING on the web about this and I've looked at a ton of medical journals about this. If anyone has a good one that explains the "why" behind why these drugs work I would appreciate it. Thanks!

[TheSquire, DNP, APRN, NP]

I challenge your assertion that there is NOTHING on the web about this topic.

If you go and google "purine analogue" the first link that is returned is to the wikipedia article for the same, which includes the sentence: "Purine analogues are antimetabolites which mimic the structure of metabolic purines." If you click through to the article on Antimetabolites it tells you that "they interfere with DNA production" and, further, that "[a]nti-metabolites masquerade as a purine...or a pyrimidine - which become the building blocks of DNA. They prevent these substances from being incorporated into DNA during the S phase... stopping normal development and division." This is cited from an oncology textbook, which your schools medical library should have a copy of (or a copy of a comparable textbook).

Basically, what happens is that the antimetabolite is incorporated into the strand by DNA synthase. Since the synthase is unable to continue the strand after the antimetabolite is incorporated, replication of that strand ceases. Do this enough times and the cell is shifted from the normal cell cycle into apoptosis.

[CBsMommy]

Thanks TheSquire. I tend to overlook Widipedia since it's not a great resource. After I posted this question, I found the information that I was looking for. Thanks for going out of your way though.

[TheSquire, DNP, APRN, NP]

Wikipedia's an ok resource - you can't take it as the final word on anything, but it can be a start for helping you figure things out.