Translator: aknv tso Reviewer: amit geva
This CT image presents a mouse's body.
A cross sectional CT image of mouse's body. This mouse has a malignant tumor.
Can you identify the location and the size of the tumor based on this image?
Diagnosticians deal with this challenge on a daily basis.
Any doctor has to deal with dozens of such images daily.
The existing means for more accurate diagnostics are not available in most medical centers, and they are very expensive.
Moreover, they allow monitoring of the effectiveness
of various treatments only after two months, at least two months of the treatment commencement.
I have chosen to deal with this challenge, and here is our discovery.
This is an image of the same body, 24 hours after injection of gold nanoparticles.
Today I am going to tell you how we reached this result, and how it works.
During my doctoral studies, I researched
the cancer, imaging techniques, treatment methods,
combination of metals, and about three years ago, I devoted my professional life for establishment of a start-up company in the field.
Well, as we all know accurate imaging capability is very, very critical
from the start of the diagnosis process. Is there a malignant tumor?
Where is it?
How big is it?
Is there only one tumor?
May there be more?
What is the type of the cells?
These are just some of the questions we have to answer
to determine the level of malignancy
and to formulate an appropriate therapeutic strategy.
The need for an accurate imaging
does not end at the stage of diagnosis.
How would we know whether the treatment is effective?
Does the treatment work at all?
Here, too, the imaging plays a crucial role.
One of the common methods for visualization
or imaging of tumors, involves
the use of ionizing radiation, known as CT scan.
During the scan of the subject's body,
due to the different densities of various tissues, we get an image.
This is possible because of the different intake of energy.
One of the best examples of this are the bones
that contain great amounts of calcium, so their density is higher.
They absorb more radiation, therefore it is easy to distinguish them
and see them in regular CT scans.
Unfortunately, the density of tumors is not
much different from the density of the surrounding tissues, making it more difficult
to see them in regular CT scans.
Sure, you can imagine the importance of early diagnosis
before it is too late.
During my doctoral studies,
I have researched and tried to develop different methods
to introduce metals into cancer cells, but unfortunately, the work done there
did not produce enough results to reach a significant breakthrough.
At that time, many questions popped up.
What about toxicity?
How can we ensure that the metal will concentrate only
within the tumor and will travel throughout the body?
However, I would never quit something because it seems to be impossible or unattainable.
Tumors have one feature that makes it possible.
Malignant tumors are much more permeable for substances from the environment.
The solution I propose is the use of nano-technology
to create gold nanoparticles, very tiny particles of gold,
which can enter and accumulate in the cancerous tissue, as opposed to healthy tissue.
Healthy tissue is much less permeable for substances from the environment,
so it will absorb far less gold nanoparticles.
The combination of unique features of the malignant tumor
with the unique features of gold nanoparticles makes this task possible.
Well, it all looks good, but what about toxicity?
I tried to solve this problem in laboratory with my team of chemists and biologists.
We have tried all sorts of ways and methods,
and it took us about three years to create a unique molecule
that bond to the surface of the gold nanoparticles.
In addition to its ability to prevent the toxic interaction of gold or metal with the body,
this molecule provides to gold nanoparticles the ability to stay in the body for a long time,
thus increasing their chances reach and accumulate in the tumor cells.
'I.e., it allows gold nanoparticles to circulate in the bloodstream for a longer period,
thus they have higher chance to and to accumulate and enter into cancer cells.
Our trials also showed that this molecule allows gold nanoparticles
to remain within the tumor itself for a long time.
We are talking about weeks.
This will allow performing a series of CT scans,
more than one, and if during a certain treatment there will be a growth or regression of the tumor,
it will be easier and faster to follow these changes within a short period without wasting precious time
that could be very critical for the patient.
So if gold nanoparticles are injected into the bloodstream they can get
specifically into the cancerous tissue,
stay there for a long time and thus they make the imaging capability better and more accurate.
In addition to their increased absorption capacity,
metals also emit secondary radiation of a different type - low energy photons and electrons.
It was found that this secondary radiation
is much more effective in destruction of cancer cells.
Therefore, both my team and I believe that during radiation treatments
our gold nanoparticles will significantly enhance the therapeutic effect of the radiation.
Thank you.