Sound Waves Can Target Lymph Nodes And Help Kill Breast Cancer Cells
A study out of Tohoku University has found that sound waves can be used to release drugs into lymph nodes infected with breast cancer cells.
Breast cancer cells are able to travel from the breast to the lymph nodes through the lymphatic system. This is the beginning of metastasis; once they breach the lymph nodes, these cells can invade other parts of the body.
Developing treatments to specifically target metastatic cells in the lymph nodes — before they are able to spread elsewhere — could vastly improve treatment outcomes. Scientists think they’ve found a way to specifically target these cells, using sound waves.
“We believe that our technique has the potential to be developed into a new treatment for lymph nodes invaded by metastatic tumour cells,” says Tetsuya Kodama, a biomedical engineer who led the study.
The study was published in Scientific Reports. The same research team behind this study had previously tried the sound wave technique on mice with a much less aggressive type of lymph node metastases.
For this study, they tried it on invasive breast cancer cells in mice.
The first thing the team did was send vesicles (tiny, fluid-filled sacs) through the lymphatic system of mice. These particular vesicles contained gas bubbles, and are called acoustic liposomes. The researchers injected these into a pelvic lymph node to see where they went, predicting they’d head up to the lymph nodes in the armpit area. They did just that, and once they reached the armpit lymph node they stayed there.
Knowing this, the team then took a different group of mice and injected breast cancer cells into their pelvic lymph nodes. These cancerous cells, like the acoustic liposomes, travelled to the armpit lymph nodes and settled there.
The team then injected vesicles carrying doxorubicin, a type of chemo drug, into the pelvic lymph nodes of the cancer-infected mice. Once these vesicles reached the cancerous lymph nodes in the armpit, the researchers hit them with high-powered ultrasound waves.
This caused the vesicles holding the drugs to rupture, releasing the potent drugs directly into the lymph nodes.
Using sound waves to burst the sacs carrying the drugs is a much more targeted approach to treating the lymph nodes with drug injections alone.
To confirm that the cancerous tissue was eradicated, the team monitored the cancer growth using a bioluminescence technique, and also biopsied the lymph nodes.
While the mice didn’t experience any side effects (which is incredible) more research is still needed to make sure lymphatic system complications like lymphedema are prevented. More research is also needed to determine the best frequency to use the treatment.
This is promising news in the arena of targeted cancer therapy.