"Nature-Nanotechnology": Adding a little nanoparticle can greatly enhance the effect of anti-cancer therapy

▎Malignant pleural effusion (MPE) is the fluid between the pleural wall and internal organs such as the lungs.
It usually includes two types of tumor microenvironment: effusion filled with tumor cells and solid tumors in the pleural cavity.
Solid tumors will be more complicated
.

In the United States alone, there are more than 200,000 new MPE patients each year, and a large part of them are from non-small cell lung cancer
.

When a patient develops MPE, it indicates that the cancer has progressed to a relatively advanced stage.
"MPE patients usually have a poor prognosis.
The patient's survival period is only 4-9 months, and they will experience severe breathing difficulties and pain symptoms," the United States Said Zhao Dawen, associate professor of Wake Forest University School of Medicine
.

According to the research published by him and his colleagues in Nature Nanotechnology, some clinical trials are currently adopting immune checkpoint inhibitors and some new immunotherapies to help treat MPE.
For example, anti-PD-1 antibodies have achieved some positive results.
, But there are still many patients who are not sensitive to immunotherapy
.

Some clinical samples of MPE showed part of the reason.
In addition to cancer cells, there are some tumor-associated immune cells (TAIC) in these effusion samples, but these immune cells are not here to help, they will instead become accomplices of cancer cells.
, Making it difficult for the immune system to recognize tumors
.

In the eyes of Dr.
Zhao, a "cold" immune microenvironment will be constructed in MPE
.

Here, cells that can hunt down tumors are very rare, which is why immunotherapy will fail
.

However, he and his colleagues designed a new nanoparticle that may change this dilemma
.

▲Nanoparticles can target macrophages in pleural effusion (picture source: reference [2]) The essence of these nanoparticles is some tiny lipid particles, and they are equipped with cyclic dinucleotides (CDN), After entering the pleural effusion, it can activate the interferon-related signaling pathways of macrophages and dendritic cells
.

This process is especially effective for TAIC, which can reprogram these cells into cancer-fighting immune cells
.

In the MPE mouse model, after they injected these nanoparticles into the chest cavity, the transcriptome of the cells in the pleural effusion began to change
.

This part of the "cold" immune effect gradually shrinks, except that the cells in the effusion will be affected, and the tumor part will also be improved
.

Image source: 123RF research team tried to use this kind of nanoparticles in combination with immunotherapy.
As a result, the capacity of MPE can be significantly reduced after a period of time.
In addition to reducing the effusion containing cancer cells, the tumor cells around the chest cavity can also be suppressed
.

Compared with the control group that received only immunotherapy, the survival time of the mice was significantly prolonged
.

In addition to mice, the researchers selected some samples of MPE patients as preclinical tests.
As a result, nanoparticles can also cause sufficient immune responses, enhance the toxicity of immune cells in the samples, and improve their efficiency in destroying tumors
.

"Whether used alone or in combination with immunotherapy, nanoparticles provide a new kind of MPE adjuvant therapy," said Dr.
Zhao.
"This will not only extend the life of patients but also improve their quality of life
.

"Reference: [1] Dawen Zhao, Intrapleural nano-immunotherapy promotes innate and adaptive immune responses to enhance anti-PD-L1 therapy for malignant pleural effusion, Nature Nanotechnology (2021).
DOI: 10.
1038/s41565-021-01032-w .
[2] Nanoparticle therapeutic enhances cancer immunotherapy.
Retrieved Dec 17th, 2021 from https://phys.
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