Nano packages for anti-cancer drug delivery

March 18, 2015, Agency for Science, Technology and Research (A*STAR), Singapore
Nano packages for anti-cancer drug delivery
Phenformin-loaded nanoparticles kill both cancer cells and cancer stem cells, leading to tumor regression. Credit: A*STAR Institute of Bioengineering and Nanotechnology

Cancer stem cells are resistant to chemotherapy and consequently tend to remain in the body even after a course of treatment has finished, where they can often trigger cancer recurrence or metastasis. A new study by researchers from the A*STAR Institute of Bioengineering and Nanotechnology has found that using nanoparticles to deliver an anti-cancer drug that simultaneously kills cancer cells and cancer stem cells significantly reduces the recurrence and metastasis of lung cancer.

The drug phenformin is very effective against cancer stem cells. It is related to the popular anti-diabetic drug metformin but is 50 times more potent against cancer cell lines. However, phenformin is too toxic in its free form to be administered to patients at the doses required to kill both normal and cancer stem cells. Now, Yi Yan Yang and her colleagues at the Institute of Bioengineering and Nanotechnology in Singapore have found a way to overcome this problem—using self-assembling polymer to deliver the drug.

In the first study to use to deliver phenformin to target both cancer cells and cancer stem cells, Yang and co-workers found that phenformin-loaded nanoparticles targeted both kinds of cancer cells in a mouse model of human lung cancer.

The nanoparticles released the drug in a sustained manner due to their hydrophilic shells, which "prevent enzymatic degradation of the cargo and protein adsorption onto the nanoparticles," explains Yang. "This also prolongs blood circulation so that the cargo-loaded nanoparticles have enough time to accumulate in tumor tissues."

This delivery method enabled Yang and her team to arrest the growth of cancer and cancer stem cells when the nanoparticles were delivered to implanted human in mice.

"The results showed that the phenformin-loaded nanoparticles were more effective than free phenformin in inhibiting the growth of both cancer stem cells and normal cancer cells," Yang says. Moreover, the nanoparticles did not induce the liver toxicity observed in systemically administered phenformin.

The method can also be extended to other drugs. The team has used the nanoparticle-based delivery system in a of human breast cancer to deliver the , doxorubicin—another drug that is toxic at certain doses but is capable of killing . "The combination shrank tumors by more than 40 per cent and was more effective than treatment with either drug alone," says Yang.

The team is now seeking to collaborate with pharmaceutical companies to bring this technology to human clinical trials.

Explore further: Promising use of nanodiamonds to kill chemoresistant cancer stem cells more effectively

More information: Krishnamurthy, S., Ng, V. W. L., Gao, S., Tan, M. H. & Yang, Y. Y. "Phenformin-loaded polymeric micelles for targeting both cancer cells and cancer stem cells in vitro and in vivo." Biomaterials 35, 9177–9186 (2014). dx.doi.org/10.1016/j.biomaterials.2014.07.018

Related Stories

Stem cells lurking in tumors can resist treatment

March 12, 2015

Scientists are eager to make use of stem cells' extraordinary power to transform into nearly any kind of cell, but that ability also is cause for concern in cancer treatment. Malignant tumors contain stem cells, prompting ...

New nanodevice defeats drug resistance

March 2, 2015

Chemotherapy often shrinks tumors at first, but as cancer cells become resistant to drug treatment, tumors can grow back. A new nanodevice developed by MIT researchers can help overcome that by first blocking the gene that ...

Recommended for you

Atomic-scale ping-pong

June 20, 2018

New experiments by researchers at the National Graphene Institute at the University of Manchester have shed more light on the gas flow through tiny, angstrom-sized channels with atomically flat walls.

Chameleon-inspired nanolaser changes colors

June 20, 2018

As a chameleon shifts its color from turquoise to pink to orange to green, nature's design principles are at play. Complex nano-mechanics are quietly and effortlessly working to camouflage the lizard's skin to match its environment.

Method could help boost large scale production of graphene

June 19, 2018

The measure by which any conductor is judged is how easily, and speedily, electrons can move through it. On this point, graphene is one of the most promising materials for a breathtaking array of applications. However, its ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.