Sprayable gel could help the body fight off cancer after surgery

December 10, 2018

Many people who are diagnosed with cancer will undergo some type of surgery to treat their disease -- almost 95 percent of people with early-diagnosed breast cancer will require surgery and it's often the first line of treatment for people with brain tumors, for example. But despite improvements in surgical techniques over the past decade, the cancer often comes back after the procedure.

Now, a UCLA-led research team has developed a spray gel embedded with immune-boosting drugs that could help. In a peer-reviewed study, the substance was successful half of the time in awakening lab animals' immune systems to stop the cancer from recurring and inhibit it from spreading to other parts of the body.

A paper describing the work is published online in the journal Nature Nanotechnology.

The researchers, led by Zhen Gu, a professor of bioengineering at the UCLA Samueli School of Engineering and member of the UCLA Jonsson Comprehensive Cancer Center, tested the biodegradable spray gel in mice that had advanced melanoma tumors surgically removed. They found that the gel reduced the growth of the tumor cells that remained after surgery, which helped prevent recurrences of the cancer: After receiving the treatment, 50 percent of the mice survived for at least 60 days without their tumors regrowing.

The spray not only inhibited the recurrence of tumors from the area on the body where it was removed, but it also controlled the development of tumors in other parts of the body, said Gu, who is also a member of the California NanoSystems Institute at UCLA.

The substance will have to go through further testing and approvals before it could be used in humans. But Gu said that the scientists envision the gel being applied to the tumor resection site by surgeons immediately after the tumor is removed during surgery.

"This sprayable gel shows promise against one of the greatest obstacles in curing cancer," Gu said. "One of the trademarks of cancers is that it spreads. In fact, around 90 percent of people with cancerous tumors end up dying because of tumor recurrence or metastasis. Being able to develop something that helps lower this risk for this to occur and has low toxicity is especially gratifying."

The researchers loaded nanoparticles with an antibody specifically targeted to block CD47, a protein that cancer cells release as a "don't-eat-me" signal. By blocking CD47, the antibody enables the immune system to find and ultimately destroy the cancer cells.

The nanoparticles are made of calcium carbonate, a substance that is the main component of egg shells and is often found in rocks. Researchers chose calcium carbonate because it can be gradually dissolved in surgical wound sites, which are slightly acidic, and because it boosts the activity of a type of macrophage that helps rid the body of foreign objects, said Qian Chen, the study's lead author and a postdoctoral researcher in Gu's lab.

"We also learned that the gel could activate T cells in the immune system to get them to work together as another line of attack against lingering cancer cells," Chen said.

Once the solution is sprayed on the surgical site, it quickly forms a gel embedded with the nanoparticles. The gel helps stop at the surgical site and promotes would healing; the nanoparticles gradually dissolve and release the anti-CD47 antibodies into the body.

The researchers will continue testing the approach in animals to learn the optimal dose, best mix of nanoparticles and ideal treatment frequency, before testing the gel on human patients.
-end-
The paper's other senior authors are Dr. Gianpietro Dotti of the University of North Carolina, Chapel Hill; Jun Wang, a professor at the National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou; and Dr. Chen Jiang of the School of Pharmacy, Fudan University, Shanghai. The other authors of the study are students and research scientists from UCLA and from China's Fudan University and South China University of Technology.

University of California - Los Angeles Health Sciences

Related Cancer Articles from Brightsurf:

New blood cancer treatment works by selectively interfering with cancer cell signalling
University of Alberta scientists have identified the mechanism of action behind a new type of precision cancer drug for blood cancers that is set for human trials, according to research published in Nature Communications.

UCI researchers uncover cancer cell vulnerabilities; may lead to better cancer therapies
A new University of California, Irvine-led study reveals a protein responsible for genetic changes resulting in a variety of cancers, may also be the key to more effective, targeted cancer therapy.

Breast cancer treatment costs highest among young women with metastic cancer
In a fight for their lives, young women, age 18-44, spend double the amount of older women to survive metastatic breast cancer, according to a large statewide study by the University of North Carolina at Chapel Hill.

Cancer mortality continues steady decline, driven by progress against lung cancer
The cancer death rate declined by 29% from 1991 to 2017, including a 2.2% drop from 2016 to 2017, the largest single-year drop in cancer mortality ever reported.

Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.

Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.

Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.

More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.

New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.

American Cancer Society outlines blueprint for cancer control in the 21st century
The American Cancer Society is outlining its vision for cancer control in the decades ahead in a series of articles that forms the basis of a national cancer control plan.

Read More: Cancer News and Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.