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Cancer Therapy with Radioactive Scorpion Venom
BostonBTS writes "Researchers from TransMolecular, Inc. have used chlorotoxin -- a component of giant yellow scorpion venom -- to target radioactive treatments for the deadly brain cancer glioma. From the article: 'In the study, 18 patients first had surgery to remove malignant gliomas, a lethal kind of brain tumor. Then doctors injected their brains with a solution of radioactive iodine and TM-601, the synthetic protein. The solution bound almost exclusively to leftover tumor cells, suggesting that it could be combined with chemotherapy to fight cancer. Furthermore, two study patients were still alive nearly three years after the treatment.' Their paper is slated for publication in the August issue of the Journal of Clinical Oncology."
RTFA:
Before you die, you see DoubleRing...
2 out of 18 is actually very good for this kind of cancer. The survival rate after three years is about 3%. 11% would be a step in the right direction, but 2/18 is way too small a sample size to really draw conclusions. It is one of the most aggressive cancers of all.
Radioactive scorpions?
It's been done.
Well, the door was open...
Hey folks -- take an honest listen for a moment. I don't want to come off as a new-age hippie, but honestly, the amazon rain forest has millions of poisonous bugs that we currently know nothing about. If you take a trip into the jungle and are a bug-watcher like I am, chances are you will see dozens of insects that currently aren't recognized by science.
The amazon jungle is full of life, and it's all practically poisonous plants and insects. Think about it -- the biggest predator in the jungle is man, and jaguars are a close second, coming in at about 70 pounds. All of the biomass in the jungle is bound up in plants and insects. There has been no downtime in the evolution of living things in the jungle for the past several million years. There is no winter, no dead non-metabolising topsoil -- animals and plants just eating and mating and reproducings generation after generation. The ethnobotanist Mark Plotkin says that the jungle is chemical warfare that has been going on for millions of years.
When I was on an excursion in the jungle of Ecuador, I decided to take a small hike during some downtime in the program. Foolishly I wore only sandals on my feet. Not 15 minutes down the trail, I felt dozens of ants biting my foot. Panicked, I reached down to brush them all off, but there was only three or four ants on my foot! When they bit into my skin, I didn't feel anything, but moments later, I would feel several bites in different places on my foot.
So my long-winded point is that there are millions of potential cancer cures out there, all kinds of medications and interesting chemicals. All of the chemical defenses plants and animals evolve work by interrupting or changing the normal cellular functioning of living organisms. The difference between medicine and poison is a question of dosage, as Plotkin paraphrased Paracelsus. We really need to work hard to make sure that this incredible resource stays around for future research. I don't know specifically what you and I can do, but awareness is the first step.
Computers are useless. They can only give you answers.
-- Pablo Picasso
Statistically, just a bit. The 10 year rate of survival for patients diagnosed with glioblastoma is 1.7%.
Also note that what they were performing isn't actually designed to destroy the cancer. They mixed this venom-derivative with a dye, and it targetted the cells correctly. When they actually use it properly, they're going to be mixing the targetting agent with something a lot more effective than an iodine dye. The 2 out of 18 thing is not an evaluation of the therapy, its noting an anomoly which a researcher presents a possible explanation for (the targetting agent itself inhibits cancerous growth). That possible explanation has neither been proved, nor is the point of this research.
Just because you're paranoid doesn't mean there isn't an invisible demon about to eat your face
Jokes aside, cost might be an issue. Scorpion venom is the most expensive liquid in the world by volume.
Yet another blogger begging for an audience.
Howdy,
e r/Sontheimer.htm). Glioblastoma is hypothesized to be so deadly because of the
ability of cancer cells inside the brain to quickly migrate from the primary site to other sites within the brain, quickly invading normal
brain tissue. This makes surgery or radiation not very effective, since migrating cells may be hidden within normal brain that is not
irradiated or cut out. The migratory ability of glioblastoma cells is related to its unique ability to change size and morphology to
move in between normal brain cells.
The effectiveness of chlorotoxin in treatment of glioblastomas was discovered by a scientist here at my institution (http://www.neurobiology.uab.edu/Faculty/Sontheim
The size-changing migratory ability is related to a specific chloride ion channel that expresses highly and uniquely on certain brain cancer cells, including gliomas (PubMed ID: 8804043, 8967454). Chlorotoxin, a chloride channel inhibitor discovered in 1993 (PubMed ID: 8383429) was more interestingly found to bind to this glioma-specific chloride ion channel in mice in 1998 (PubMed ID: 9809993) and humans in 2002 (PubMed ID: 12112367). Although it was shown that chlorotoxin failed to inhibit migratory ability due to size-change, chlorotoxin was shown to inhibit migration by inhibition of another protein involved in breaking down the extracellular matrix, allowing cells to more easily migrate.
The strategy that TransMolecular uses to treat gliomas lies in the specificity of expression of the channel to which chlorotoxin binds. That channel is expressed on the vast majority of glioma tissue samples tested, and only rarely on normal tissue. If one attaches a weak or short-lasting radioactive moiety to chlorotoxin, a potential treatment can be to target glioma cells using chlorotoxin, and then kill them by short-lasting localized radiation. This strategy is already being used in Non Hodgkins Lymphoma and other diseases by attaching to tumor- targeting antibodies a radioactive iodine atom.