Cancer patients have yet another light on the horizon for treatment thanks to U researchers.

Fred West and Charles Grissom used vitamin B12 with anti-cancer drugs to help combat the disease. Courtesy Photo/Daily Utah Chronicle

Charles Grissom and Fred West, associate professors of chemistry at the University of Utah, have developed a new way of combating cancer.

"The goal is to get more of the cancer drug into the cancer cells and not harm the healthy cells," Grissom said.

They have combined anti-cancer drugs with vitamin B12, a vitamin that is needed by cells that divide often.

"Cancer cells are rapidly dividing cells and they need B12 in order to replicate their DNA prior to cell division," Grissom said. "Cancer cells seem to have an increased requirement for vitamin B12, even greater than other dividing cells."

According to Grissom, one way to describe the drug is as a type of Trojan horse.

"A Trojan horse is a very good metaphor," he said. "The cell is presented with something that looks attractive and takes it inside, and then the [infecting] cell releases its potent payload and kills the cell."

A conventional cancer drug, such as doxorubicin, is attached to vitamin B12, forming a bioconjugate. They are joined by a linker molecule.

"[The linker] is typically a three to five carbon molecule," Grissom said. "The exact linker we use depends on the properties we want the bioconjugate to have."

One of the impressive benefits of this research is the discovery that the new drugs will not affect other body cells as previously used cancer drugs have.

"One way to use [the new drugs] is to go ahead and put up with the toxic side effects, but be able to nuke the tumors with a lot more drug," West said. "The other thing you could do is just reduce the dose, get the same level of tumor damage, but little or no side effects."

However, the researchers do not yet know if this will cut down on the typical effects chemotheraphy on a patient. They do not know if patients will experience such side effects as hair loss that have been associated with cancer treatment in the past.

"Chemotherapy agents are going after the healthy cells in the body," West said. "The most straightforward way to answer that is that we are trying to find that out right now."

"Doxorubicin turns out to be a really effective anti-cancer drug," West said. "It doesn't get used as much as people would like because it has this unintended effect of causing irreparable heart damage. A typical adult can only tolerate a few hundred milligrams in a lifetime."

"We think that using this targeting technique is really going to be good for a drug like that because heart tissue doesn't have a need for vitamin B12," West said.

Originally, the researchers were not working on this project; instead, there were doing "basic research," both Grissom and West said.

"One interesting aspect of this research is that it illustrates nicely how basic research can lead to unanticipated applied avenues of research," Grissom said.

"None of this would have been possible without the basic research," West said. "I think it's just important to realize that out of some fairly unfocused research, can come some applied results like this. Sometimes people need to be reminded that sometimes creating knowledge can lead to something that's fundamentally useful."

The drug has a long way to go before it reaches the medication stage. "Before you can even think about human clinical trials, you've got to do some really extensive pre-clinical animal studies to get some sort of fairly clear notion of what kind of toxicity you would expect in human patients," West said. "We're not far enough along to see the light at the end of the tunnel."