Mayo Clinic researchers develop new tumor-shrinking nanoparticle to fight cancer, prevent recurrence

May 01, 2017

JACKSONVILLE, Fla. -- A Mayo Clinic research team has developed a new type of cancer-fighting nanoparticle aimed at shrinking breast cancer tumors, while also preventing recurrence of the disease. In the study, published today in Nature Nanotechnology, mice that received an injection with the nanoparticle showed a 70 to 80 percent reduction in tumor size. Most significantly, mice treated with these nanoparticles showed resistance to future tumor recurrence, even when exposed to cancer cells a month later.

The results show that the newly designed nanoparticle produced potent anti-tumor immune responses to HER2-positive breast cancers. Breast cancers with higher levels of HER2 protein are known to grow aggressively and spread more quickly than those without the mutation.

"In this proof-of-concept study, we were astounded to find that the animals treated with these nanoparticles showed a lasting anti-cancer effect," says Betty Y.S. Kim, M.D., Ph.D., principal investigator, and a neurosurgeon and neuroscientist who specializes in brain tumors at Mayo Clinic's Florida campus. "Unlike existing cancer immunotherapies that target only a portion of the immune system, our custom-designed nanomaterials actively engage the entire immune system to kill cancer cells, prompting the body to create its own memory system to minimize tumor recurrence. These nanomedicines can be expanded to target different types of cancer and other human diseases, including neurovascular and neurodegenerative disorders."

Dr. Kim's team developed the nanoparticle, which she has named "Multivalent Bi-specific Nano-Bioconjugate Engager," a patented technology with Mayo Clinic Ventures, a commercialization arm of Mayo Clinic. It's coated with antibodies that target the HER2 receptor, a common molecule found on 40 percent of breast cancers. It's also coated with molecules that engage two distinct facets of the body's immune system. The nanoparticle hones in on the tumor by recognizing HER2 and then helps the immune cells identify the tumor cells to attack them.

The molecules attached to the nanoparticle rev up the body's nonspecific, clean-up cells (known as macrophages and phagocytes) in the immune system that engulf and destroy any foreign material. The design of the nanoparticle prompts these cells to appear in abundance and clear up abnormal cancer cells. These clean-up cells then relay information about the cancer cells to highly specialized T-cells in the immune system that help eradicate remaining cancer cells, while maintaining a memory of these cells to prevent cancer recurrence. It's the establishment of disease-fighting memory in the cells that makes the nanoparticle similar to a cancer vaccine. Ultimately, the body's own cells become capable of recognizing and destroying recurrent tumors.

Since the late 1990s, the field of nanomedicine has focused on developing nanoparticles as simple drug delivery vehicles that can propel chemotherapy drugs to tumors. One pitfall is that the body tends to purge the particles before they reach their destination.

"Our study represents a novel concept of designing nanomedicine that can actively interact with the immune cells in our body and modulate their functions to treat human diseases," says Dr. Kim. "It builds on recent developments in cancer immunotherapy, which have been successful in treating some types of tumors; however, most immunotherapy developed so far does not harness the power of the entire immune system. We've developed a new platform that reaches tumor cells and also recruits abundant clean-up cells for a fully potent immune response."

Future studies in the lab will explore the ability of the nanoparticle to prevent long-term recurrence of tumors, including metastases at sites distant from the primary tumor. What's more, the nanoparticle is designed to be modular, meaning it can carry molecules to fight other types of disease. "This approach hopefully will open new doors in the design of new nanomedicine-based immunotherapies," she says.
-end-
The other authors on this study include:This multi-institutional study was developed in collaboration with Wen Jiang, M.D., Ph.D., in the Department of Radiation Oncology at the University of Texas M.D. Anderson Cancer Center.

This work was supported by the Department of Neurosurgery at Mayo Clinic's Florida campus; James C. and Sara K. Kennedy Fund for Neurodegenerative Disease Research at Mayo Clinic in Florida; Jorge and Leslie Bacardi Fund for Regenerative Medicine in Florida; Mayo Clinic Center for Regenerative Medicine; Robin L. and Louis V. Gerstner, Jr. Career Development Award in Individualized Medicine; Helene Houle Career Development Award in Neurologic Surgery Research; Fund for the Center for Regenerative Medicine Program Director, Neuroregenerative Medicine; Regenerative Medicine Initiative for Neuro-Oncology Research; China Scholarships Council; and through the generous support of Richard D. and Darlene R. DeMars, and David U. and Frances S. Strawn.

About Mayo Clinic

Mayo Clinic is a nonprofit organization committed to medical research and education, and providing expert whole-person care to everyone who needs healing. For more information, visit mayoclinic.org or newsnetwork.mayoclinic.org.

Mayo Clinic

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.