Nanoparticles Could Slow Down Tumor Growth, Stop Breast Cancer from Spreading

Researchers from University of Cincinnati Academic Health Center have discovered that nanoparticles could be a solution to making breast cancer treatments more effective as it can slow down tumor growth, sensitize cancer cells and stop breast cancer from spreading.

The study, entitled "Overcoming Tamoxifen Resistance of Human Breast Cancer by Targeted Gene Silencing using Multifunctional pRNA Nanoparticles" published in the journal ACS Nano, says that the scientists have developed multifunctional RNA nanoparticles that can overcome breast cancer treatment resistance.

Using a nanodelivery system, the researchers target the MED1, a protein that triggers tumor growth, and HER-2 positive breast cancer. They also used tamoxifen to sensitize the cancer cells.

"Most breast cancers express estrogen receptors, and the anti-estrogen drug tamoxifen has been widely used for their treatment. Unfortunately, up to half of all estrogen receptor-positive tumors are either unresponsive or later develop resistance to the therapy. In this study, we have developed a highly innovative design that takes advantage of the co-overexpression of HER2 and MED1 in these tumors," Xiaoting Zhang, Ph.D., associate professor in the Department of Cancer Biology at the UC College of Medicine and lead author of the study, said via Science Daily.

The nanoparticle that Zhang and his team created is powerful enough to "selectively bind to HER2-overexpressing breast tumors." Through this, MED1 was significantly decreased. The team administered these bio-safe nanoparticles to animals for the study.

"These nanoparticles also led to a dramatic reduction in the cancer stem cell content of breast tumors when combined with tamoxifen treatment. Cancer stem cells, as you know, are tumor-causing cells that are known to play essential roles in tumor spread, recurrence and therapy resistance. Eliminating these cells could represent an improved and more desirable treatment strategy for breast cancer patient," Zhang said.

Zhang said that the new discovery leads to more effective clinical treatment of breast cancer, but further research is still needed.