Nanoscale capsule kills cancer cells without harming healthy cells
February 8, 2013
A diagram of the synthesis of degradable nanocapsules into cell nuclei to induce apoptosis, or programmed cell death, in cancer cells. The nanocapsules degrade harmlessly in normal cells. (Credit: UCLA Engineering)
A degradable nanoscale shell to carry proteins to cancer cells and stunt the growth of tumors without damaging healthy cells has been developed by a team led by researchers from the UCLA Henry Samueli School of Engineering and Applied Science.
Tiny shells (about 100 nanometers in length, roughly half the size of the smallest bacterium) are composed of a water-soluble polymer that safely delivers a protein complex to the nucleus of cancer cells to induce their death. The shells degrade harmlessly in non-cancerous cells.
The process does not present the risk of genetic mutation posed by gene therapies for cancer, or the risk to healthy cells caused by chemotherapy, which does not effectively discriminate between healthy and cancerous cells, said Yi Tang, a professor of chemical and biomolecular engineering and a member of the California NanoSystems Institute at UCLA.
“This approach is potentially a new way to treat cancer,” said Tang. “It is a difficult problem to deliver the protein if we don’t use this vehicle. This is a unique way to treat cancer cells and leave healthy cells untouched.”
Treatment of apoptin nanocapsules resulted in tumor growth retardation from apoptosis (green) (credit: UCLA Engineering)
The cell-destroying material, apoptin, is a protein complex derived from an anemia virus in birds. This protein cargo accumulates in the nucleus of cancer cells and signals to the cell to undergo apoptosis (programmed self-destruction).
The polymer shells are developed under mild physiological conditions so as not to alter the chemical structure of the proteins or cause them to clump, preserving their effectiveness on the cancer cells.
Tests done on human breast cancer cell lines in laboratory mice showed significant reduction in tumor growth.
Tang’s group continues to research ways of more precisely targeting tumors, prolonging the circulation time of the capsules, and delivering other highly sought-after proteins to cancer cells.
The research was funded by the David and Lucille Packard Foundation and a breast cancer research grant from the Congressionally Directed Medical Research Program.
Comments (9)
by dlr
This is a pathetically inadequate article. Why/how do the shells ‘degrade harmlessly in non-cancerous cells’?
by MikeB
So … there’s two stories here, right, the protein and the delivery shell. How well does the shell survive the immune system? How long does biodegradation take and can it be controlled? What remains after degradation and what are the properties of those remnants? What are the ramifications If the shell degrades before delivery and the protein is released outside the shell? When those questions and more are answered, then the technique should be implemented widely … until then lets let the process unfold. Sometimes the answer is ‘No, not yet.’ and it really is better for all concerned.
by beatriz valdes
When available to patients? Scientists must find a way to move the whole process from discovery to availability much faster. Use the supercomputers, the robots, all the technology available: and government should fund promising enterprises, such as this. Not a patient cancer, TG but can empathize with sick people, desperate for these cures!
by Bri
I agree with the sentiment of this post. Many of us have called out for a streamlining of the approval process( brings new meaning to ” awaiting approval”). I’m sure there would be thousands of not millions of terminally ill cancer patients that would be willing to subject themselves to higher levels of risk.
by melajara
Exactly, and the so called FDA “fast track” has to be speeded up. If the nation were in war, facing a pandemic, solutions would be found illico, but indeed there is a war, a war against cancer. Do you remember Nixon’s War on Cancer declaration? (http://en.wikipedia.org/wiki/War_on_Cancer) Gosh, this was 41 years ago!
by Aaron Wright
A doctor once explained to me that the problem with allowing people to experience more risk for a possible cure is that too many patients want to jump right in to the “possible cure” without trying other things first. They don’t fully understand the risks involved with experimental treatments. We see this in other areas like when patients ask for antibiotics for a viral infection, and the doc gives it to them to make them happy (contributing to antibiotic resistance). While I agree that the FDA process should speed up, we also need doctors willing to say no to patients.
by Gabriel
That’s always been a stark contrast….it’s always wonderful to read articles like these, but you walk in the doctor’s office, and nothing seems any different then it was decades ago. All the innovations in the world won’t matter if they aren’t available for patients to actually use.
by Minhaj Arifin, Author How Desis Became the Greatest Nation on Earth
well said. We need to make this happen.
by JC
Were you able to tell what feature of the cancer cell causes the protein to “selectively accumulate in the nucleus” ?