Nat Biomed Eng: A miniature, implantable therapeutic sponge device that has the potential to kill cancer cells in the body

Solid tumors are partially tolerant to therapy through human biology and autoresistance, and tumors often surround themselves with extra white blood cells called regulatory T cells, which evoke the body's natural defense mechanisms
against disease.
The strategy of inactivating these cells often leads to other serious problems, because regulatory T cells play an important role in protecting healthy tissues in the body, reducing these cells throughout the body may cause other immune cells to mistakenly attack these tissues and induce autoimmune diseases, as well as damage to the colon, liver, heart and other organs
.

Recently, a study entitled "Systemic enhancement of antitumour immunity by peritumourally implanted immunomodulatory macroporous scaffolds" published in the international journal Nature Biomedical Engineering, Scientists from UCLA and other institutions have reported exciting findings by testing an implantable device called SymphNode, which is designed to help control regulatory T cells only in the area around tumors, while also summoning and strengthening the function of defense against tumor cells, which can also promote tumor remission, eliminate cancer metastasis, prevent the growth of new tumors, and prolong the survival of mice
.

Researcher Manish Butte said that getting rid of regulatory T cells inside tumors, which are filled with these cells in every solid tumor, are responsible for 91% of cancer deaths due to solid tumors, and limit scientists' ability to
treat cancer 。 SymphNode is a miniature, biodegradable sponge about the size of an eraser, composed of alginate, and the same jitter polymer used to thicken pudding; When surgically implanted directly into a tumor, this sponge structure stimulates the body's immune response against cancer in a variety of ways, slowly releasing drugs to block the function of regulatory T cells in tumors, and at the same time, attracting and enhancing the function of tumor-killing T cells, similar to lymph nodes, which are a very welcoming environment for cancer-fighting cells, and containing antibodies in its pores that can further activate these cells
.

A miniature, implantable therapeutic sponge device may have the potential to kill cancer cells
in the body.

Image source: Nature Biomedical Engineering (2022).
DOI:10.
1038/s41551-022-00977-0

The researchers then tested SymphNode in mouse models with breast cancer and melanoma, which can shrink tumors in 80 percent of mice and prevent cancer from spreading in 100 percent of mice.
In contrast, the cancer metastasized to the brains and lymph nodes of untreated control mice and killed the mice within a few weeks, and the researchers also found that placing SymphNodes near breast cancer tumors may hinder the growth
of secondary tumors at different sites in the body.
In melanoma mice, the device caused tumor shrinkage in 100 percent of treated mice, and tumor reduction to undetectable levels in more than 40 percent of mice, significantly extending the lifespan of mice in both cancer types, and in many cases more than
twice as much as untreated mice.
Most hopefully, they show that mice that survive SymphNode treatment for breast cancer also resist the growth of the first secondary tumor 100 days after the injection, suggesting that the technique may reduce the risk of
cancer recurrence.

Researcher Butte said this may be due to the activity of memory T cells, which train immune cells to quickly recognize and help fight off the same cancer
in later encounters, according to the researcher.
Very few cancer therapies on the market seem to enhance the function of memory T cells in a similar way and prevent tumors from returning
.
Symphony is currently developing a small, injectable version of SymphNode that the researchers envision as a potential complement to chemotherapy or the first step in the treatment of multiple cancers, initially in triple-negative breast cancer, a disease that lacks targeted therapies and clinical trials that could begin sometime in 2024
.

In summary, the results suggest that immunoregulatory stents implanted around tumors may represent a common strategy to enhance the immunity of T cells and avoid the toxic effects
of systemic therapy.
(Biovalley Bioon.
com)

Original source:

Majedi, F.
S.
, Hasani-Sadrabadi, M.
M.
, Thauland, T.
J.
 et al.
 Systemic enhancement of antitumour immunity by peritumourally implanted immunomodulatory macroporous scaffolds.
 Nat.
Biomed.
Eng (2022).
doi：10.
1038/s41551-022-00977-0