The main factor involved in fatal cases of cancer is metastasis, when cancer spreads from the original tumor to different parts of the body. A new study claims to found a way to stop cancer cells from migrating to other body parts, a key process in metastasis. The team believe their discovery could one day lead a treatment that could slow down this process or even stop it all together.
The researchers were able to use nanotechnology to create extremely small materials that prevent cancer cells from moving, or what they call, “breaking cancer's legs.” If the cancer can't move, it can't metastasize.
"If cancer stays in a tumor in one place, you can get to it, and it's not so likely to kill the patient, but when it spreads around the body, that's what really makes it deadly," said lead researcher Mostafa El-Sayed, in a press release. "The method appears to be very effective as a locally administered treatment that also protects the body from cancer's spread away from the treated tumors, and it is also very mild, so it can be applied many times over if needed."
Cells move using leg-like protrusions called filopodia, but cancer cells produce far more of these than healthy tissue. While cancer cells that try to spread usually die at some point in the process, if conditions are favorable, the cancer can successfully form a tumor in another part of the body.
The team was able to obstruct the movement of these filopodia using gold nanoparticles specifically designed so that they only block the function of cancer cells and do not interfere with healthy cells.
The team found that shining a low-energy laser at the cells caused the cell movement to stop completely. The laser caused the gold to heat up and partially melt the cancer cells legs, completely stopping their movement.
"This gentle laser didn't burn the skin or damage tissue, so it could be dosed multiple times and more thoroughly stop the cancer cells from being able to travel," explained study researcher Ronghu Wu in a statement.
According to the National Cancer Institute, metastasis is the main reason that cancer is so deadly. In addition, the metastatic cancer cells can remain inactive on a site for many years before they begin to grow again.
When the cells move to other nearby tissue, it can be very difficult to control. This type of cancer is largely untreatable. Most treatment for metastasized cancer aims to stop or slow down its spread. Some of the most common sites of metastasis are the bone, liver, and lung.
Although the treatment is still in the research phase, the team see it being used for head, neck, breast and skin cancers with direct local injections. They also suspect they would be able to treat deeper cancer using a fiber optic or endoscopic laser.
Source: Ali MRK, Wu Y, Tang Y, et al. Targeting cancer cell integrins using gold nanorods in photothermal therapy inhibits migration through affecting cytoskeletal proteins. PNAS . 2017