Virus Tamed To Attack Cancer, Cancer Drugs To Treat Alcoholism 128
ScienceDaily is reporting that scientists at Oxford University seem to have adapted a virus so that it attacks cancer cells but does not hurt healthy cells. "Adenovirus is a DNA virus widely used in cancer therapy but which causes hepatic disease in mice. Professor Len Seymour and colleagues found that introducing sites into the virus genome that are recognized by microRNA 122 leads to hepatic degradation of important viral mRNA, thereby diminishing the virus' ability to adversely affect the liver, while maintaining its ability to replicate in and kill tumor cells." Relatedly, cancer drugs already approved for use may be cross-functional as a treatment for alcohol addiction. "Now, the researchers show that flies and mice treated with erlotinib also grow more sensitive to alcohol. What's more, rats given the cancer-fighting drug spontaneously consumed less alcohol when it was freely available to them. Their taste for another rewarding beverage -- sugar water -- was unaffected."
Replication is dangerous (Score:5, Informative)
John Titor (Score:3, Informative)
Re:Fungus in my cancer? More likely than you think (Score:4, Informative)
Re:Pay more attention to comics and movies... (Score:2, Informative)
Because we all know that movie script writers always do their homework to get their science right
Well, they did their homework pretty well in "I Am Legend".
Everybody knows that the only way to survive the Zombie movie is with a 12-gauge shotgun. Will Smith's character uses the M4 carbine, and dies. His companion, Alice Braga's character, uses a shotgun and survives. QED
Re:Pay more attention to comics and movies... (Score:2, Informative)
I am legend the book was about the story he just said. One guy thought he was the only survivor, but lived ONLY during the day. As such, he never saw the "crazy vampires" at night. SOME of them were indeed insane.. but most of them were normal people that just looked crazy. Anyways, "Legend man" slaughtered a ton until they tricked him with a little girl.. then at the end they tell him they are killing him because HE is the "vampire" like creature. Thus.. HE is THE legend.
Re:I know that nobody cares, but... (Score:3, Informative)
Re:Replication is dangerous (Score:3, Informative)
'In any virus intended for therapeutic use in humans, allowing the virus to retain its reproductive mechanisms is just a bad idea.'
Not necessarily. Obviously there are risks (and this is just a proof of concept experiment), but as the original paper explains:
http://dx.doi.org/10.1371/journal.ppat.1000440 [doi.org]
'Viruses have a highly successful history as prophylactic vaccines and are also being developed for their intrinsic anticancer activities. In both settings the ability to undergo restricted replication is highly desirable. Attenuated (but not killed) viral strains often represent the most effective viral vaccines, affording the possibility of persistent low level infection without significant pathology.'
In other words, you want the virus to replicate in a controlled way, so that (e.g.) it hits more cancer cells than a non-replicating vector. Traditionally, 'attenuated' viruses have been used for vaccines and for anti-tumour experiments, but this tends to make them less effective than they might otherwise be. The trick they've used in this paper is selective attenuation - they've inserted an 'off switch' that responds to a microRNA that's expressed in liver (where the virus might do harm), but not elsewhere (where the virus is needed). Also, the adenovirus used in these studies isn't some exotic replicating construct with a deadly payload, but a rather common virus that generally causes mild disease even in its unattenuated form. It may not even be necessary to deliver a foreign gene to the tumour - replication-selective but otherwise normal adenoviruses can have intrinsic anti-tumour ('oncolytic') activity if they are engineered to prefer replicating in tumour cells. One common strategy is to delete a viral gene normally used to evade the cell's p53 response. The virus can then only replicate in cells with an already damaged p53 pathway (like many tumour cells!):
http://www.jci.org/articles/view/9762 [jci.org]
Re:Replication is dangerous (Score:5, Informative)
'Not as dangerous as you'd think...Viruses pick up DNA strands from the host as they are made by the hosts cells, this is primarily what causes rapid mutation and why H1N1 contains human, swine, and avian DNA-this strain has been transmitted between these three animals'
The Flu virus is a rather unusual case - its genome (in fact RNA rather than DNA) is made up of 8 segments that can easily be swapped around ('reassorted') when two different strains infect the same animal (8 segments with 2 versions of each = 2^8 = 256 possible new viruses). This isn't true for the adenovirus used in the article, which has an unsegmented DNA genome, but there's still some concern that a therapeutic strain might 'recombine' with a wild-type strain:
http://vir.sgmjournals.org/cgi/content/full/89/2/380 [sgmjournals.org]
This is one reason why you have to be careful when adding (e.g.) new genes to viruses of this type (as in gene therapy). It's rather less of a concern when doing the sort of experiment described in the original article, where the replication of the virus is partially blocked rather than enhanced, and where no new genes are added.
Re:I know that nobody cares, but... (Score:4, Informative)
The basis of the treatment can be summed up fairly quickly. Drinking alcohol releases endorphins, and the endorphins addict us to the alcohol with a force identical to morphine addiction. Taking an endorphin blocker results in a reversal of this effect, where drinking makes you loose interest in drinking over time.
The treatment that results from this effect is equally simple. You have the alcoholic take an endorphin blocker (naltrexone is typical) and then have them pursue their normal drinking habits. After about three to six months, 78% have significantly reduced desire to drink, 25% just stop drinking and have no desire to pick it back up again. I think you can see how this would put Betty Ford out of business and is indirect opposition to AA.
The fine details are a little more complicated, but only because it goes against a lot of logic. For instance, most people expect it to have a "diet pill" effect where it suppresses your urge to drink, and that's how the naltrexone tends to be prescribed. Used this way you'd actually have better results with a placebo, and people give up when it doesn't work that way.
But they wouldn't have to write a book if there were nothing else to say, would they?
Re:For Laymen.. (Score:3, Informative)
Totally not your fault. My comment about the two stories being unrelated was something of a snide jab at the "relatedly" claim made in the summary.
So, article #1 is talking about the use of a modified virus to target a cancer. Actually, to be more accurate, it's talking about modifying a virus to avoid causing liver damage while killing cancer cells.
Apparently, the adenovirus strain that they used in this trial does a good job of killing cancer cells. However, it also does a good job of killing liver cells.
What they did was introduced a liver-specific microRNA binding site to the virus. Therefore, when the virus infects the liver and produces RNA, the liver's naturally-produced microRNA will recognize this and bind to it. That's all in the article, but I'll extrapolate and assume that the body's typical dsRNA mechanisms kick in at that point, destroy the RNA, and possibly induce an antiviral response.
So essentially, it appears that they're using a virus that is good at killing cancer but is also good at destroying the liver, and they're attaching a liver-specific "kill me" tag so that the liver can protect itself.
Re:I know that nobody cares, but... (Score:3, Informative)
Ya think!?!?! The problem is that although the SC has ruled on the matter, nobody seems to care. Unless you have an attorney who knows what he's doing in this area, you can be sentenced to a religious organization for "treatment". Universities and Jobs coerce AA too, and good luck fighting them on it. There are too many members out there, and unlike most religions, you don't know who they are. What's so bad about it, other than principle? Well. despite the fact that AA gets 70% of it's membership from the health care and justice systems, there is the problem of people getting sucked in by cult-like means of deception.
Put yourself in the position of some shmo who for whatever reason (maybe with cause, maybe not) gets sent to a 12 step "recovery" group. Well. The "recovery" thing is sort of deceptive as they don't actually cure anything. There is frighteningly little in 12 step groups about actually quitting much of anything (save critical thinking which is referred to as "stinking thinking" in AA). "Recovery" in AA means lifelong meetings, relationship with a higher power, and strict adherence to AA doctrine which 12 steppers believe is "god inspired" through Bill Wilson (who was actually not that nice a charachter). I have no problem with religions if they advertise accurately, but AA masquerads as something it isn't, and loads it's language to decieve outsiders into believing it's something it's not. The lack of informed consent is what makes AA more cult-like than religion. People come in looking for help to quit drinking (or not) and are told that the *only* way is with AA and it's religious principles... or you *will die*.
So how did AA get so popular? Well. Couple reasons. 12th step, for one, is built in evangelism. You don't always know who they are. They don't advertise. They're anonymous after all. Secondly, oodles of people believing they have been helped, when often they're worse off. It's anecdotal evidence. What else do you expect. Thirdly, AA front groups like Hazelden have actively lobbied judges and others in authority.
End result of all this is religion in government and science gone down the pan.