A virus to kill cancer


Viruses spread by infiltrating the cells of their host. Normally, the detection of an intruder by a cell triggers a process called apoptosis, which causes the cell to commit suicide and prevents the virus spreading further. However, viruses can carry genes that allow them to slip past this cell death process in normal cells, causing infection.

The UK researchers deleted one such gene in an adenovirus. This meant that the virus was immediately detected by normal cells and was unable to spread. But in cancer cells, which grow uncontrollably and ignore the cell death process, the virus was able to thrive and spread rapidly. It then multiplied so vigorously that it killed the cancer cells by making them explode.

“The great thing about this strategy is that the cancer cell does all the hard work,” says Nick Lemoine, director of the Cancer Research UK Clinical Centre at Bart’s Medical School, who led the team. “It makes more and more virus to infect its neighbouring cancer cells. But if a normal cell is infected, it commits suicide before it can make new virus and spread of the virus is contained.”

I guess as long as the virus itself doesn’t kill you, great.

So this “cure” causes cancer cells to mass-produce viruses which kill one healthy cell each? Um… I guess its use will be restricted to early stages of cancer.

Not quite…

When I first read this I was optimistic, but the more I read and think through the process, the more it really just sounds more like a new, maybe slight more effective, version of chemotherapy. I’m still optimistic, but much more cautiously so.

The virus is GMed to remove the gene that masks the virus from cellular apoptosis defenses (essentially cellular suicide). So a normal cell will see the virus, go through apoptosis, and not get infected so the virus can’t propogate. Cancer cells, however, don’t trigger apoptosis, so they get infected and the virus is able to reproduce and propogate to surrounding tissue until the cell dies from virus overpopulation. Essentially, every cell that the virus tries to infect will die through apoptosis or virus overpopulation, but it only infects cancer cells and non-cancer propogation is minimal. To speed cancer cell death, they’re looking to GM in a gene that will be toxic to cancer cells.

Now if there was a way to deliver this virus to just cancer cells, you’d have a pretty effective treatment.

good news: your cancer is gone.
bad news: your leg just fell off.

Keep in mind that “[f]rom 50 to 70 billion cells die each day due to apoptosis in the average human adult. In a year, this amounts to the proliferation and subsequent destruction of a mass of cells equal to an individual’s body weight…” So what I assume would happen is that you’d have some minimal apoptosis in and around the bloodstream and right around the tumor itself, but it probably wouldn’t spread too much. Not enough for like your wang to drop off or anything.

My wang is safe? Oh good. I wasn’t so concerned about the leg part… I just wanted to know if Mr. Happy would survive the procedure.

Yes, but you still won’t be able to find any use for him.

This is an important point for all you suffering potential wang seperation anxiety:

The gene the team deleted from the adenovirus is called E1B-19kD. But, as well as removing the cloak the viruses normally use to evade detection by cells, it had another “unexpected” effect, says Lemoine.

You’re worrying over a problem the scientists already anticipated. Indeed, the point at first was to introduce a virus that couldn’t spread to normal cells by typical means (disguise). The bioengineered adenovirus was set up from the get-go to lack the ability to evade detection by the body’s immune response - evidently, it was in testing that very trait that scientists discovered the serendipitous bonus in that it blows up cancer cells. So, you get some (not much) local tissue necrosis along with all cancer cell necrosis after injection (directly into the tumor) of the virus. Unless you got cancer of the prick, you should be fine.