[♪ INTRO]
Every year, hundreds of millions of dollars go into cancer research.
And a big portion of that goes to finding new, efficient treatments.
We’ve talked about some of those before, but there are some really creative
solutions we’ve never touched on, like treating or even reversing cancer...
with electricity.
We’re not talking about zapping away tumors, though.
This research is all about harnessing electricity found in an unexpected place:
the human body.
In living things, cells generate electric current.
This is called bioelectricity, and it’s a major way cells operate.
Basically, it involves electrically-charged atoms, or ions,
moving across a cells’ outer membrane.
Normally, these membranes only let through ions with a certain charge —
exactly which depends on the cell.
But the end result is that you end up with more positive or negative ions
on one side of the membrane than the other.
In other words, there’s an imbalance in electrical charge inside and outside the cell
called an electric potential.
Then, when the cell is activated, channels in the membrane open up,
and a surge of ions is allowed through.
And the rush of charged particles makes an electric current.
All cells use bioelectricity for basic tasks, like breaking down sugars.
And some cells use it for more specific jobs.
For instance, muscle cells use bioelectricity to contract muscles.
The convenient thing is, we can detect these currents even far away from a cell,
so doctors use them all the time to monitor people’s health.
Like, they might study the heart’s electrical activity using an electrocardiogram.
But we’re not just stopping there:
Scientists have also been looking for ways to use bioelectricity to heal the body.
Since we use currents for a lot, there are several ways you can approach this.
But when it comes to fighting cancer,
it helps to know about how we’re using bioelectricity to affect cell development.
Before you had a liver and a brain, you had stem cells:
cells that could turn into all kinds of tissue.
And the thing about stem cells is, if you look at how strong their bioelectric signals
are and how they’re distributed across an area, you can learn something:
You can tell what kind of tissue or structure they’re going to become.
You can read those signals and figure out if something is going to become
a brain cell or bone cell or blood cell.
And this process can actually be altered by raising or lowering the electric potential
using drugs or other methods that open and close ion channels.
So by manipulating bioelectricity, you can make a stem cell change what it becomes!
By doing this, researchers have given function to eyes implanted on the backs of
tadpoles, controlled the regeneration of flatworms,
and corrected birth defects in developing frog embryos.
And it’s possible that these methods could also be used
to turn cancerous cells into normal, healthy ones.
See, compared to other cells, cancer cells have more positive electric charge
when they're resting — which isn’t great.
Evidence suggests this positive state is a signal
for cells to keep developing, dividing, and spreading.
So, if we could lower that electric charge using drugs or other methods —
like how we can manipulate stem cells — we could change how cancer acts.
But this is more than a hunch:
So far, scientists have found success in rats with prostate cancer,
and cancerous breast cells in a dish.
By controlling ion channels and what molecules move through them,
they reduced the number of positive ions in the cell
and even changed the cell's overall charge to negative.
By doing this, they’ve been able to stop the number of cancer cells from increasing
and even turn cancer cells into normal, healthy ones.
Besides being an incredible feat of science,
being able to control individual cells like this could eventually mean we can
move away from the harmful side effects caused by chemo and radiation therapy.
The current downside is, ion-targeting drugs have their own set of
harmful side effects, like irregular heart rhythms.
But one group has found another way to do this.
Their experiment was published in 2016 in the cancer journal Oncotarget,
and it had two main parts:
First, they injected a gene into frog embryos that caused tumor-like structures —
ones that behave similarly to the positively-charged tumors seen in humans.
Then, they injected a special, light-sensitive gene.
Essentially, it makes some of the embryo’s cells respond to light —
so, when the researchers shined a laser on those cells,
their ion channels would open or close.
It’s a method called optogenetics.
In their study, when the team shined the laser right after injecting both genes,
the embryo’s ion channels opened, and positively-charged ions rushed out,
resulting in cells becoming negatively-charged.
This prevented tumors from forming 32 percent of the time.
And what’s even better?
In another trial, when the team waited for tumors to form
before shining the light, they were able to convert fully developed tumors
back into normal cells.
Basically, they reversed cancer.
Of course, translating these methods to humans won't be easy.
Cells are extremely complicated, and there are still a lot of variables to consider
and aspects of bioelectricity we still don’t understand.
But, through more research and testing, we could one day control cancer
by using this incredible system already in our bodies.
Now, to zoom way out for a second… space.
There are pretty incredible things out there, too.
Like, in 2000, a group of satellites starting orbiting Earth
and uncovering the mysteries of our planet’s magnetic field.
The mission is called Cluster, and we’re featuring it as August’s Pin of the Month!
If you want to learn more about why we love the mission,
you can watch our video about it on SciShow Space.
And if you want the pin — well, it’s only available until the end of the month!
You can find it at DFTBA.com or in the merch shelf below.
[♪ OUTRO]