Obviously there are many treatments for cancer, including other treatments for prostate cancer. Provenge is classified as a vaccine because of its use of immunotherapy – its ability to stimulate the immune system to higher levels of antibodies (white blood cells containing proteins that attack this specific form of cancer). The process of creating the vaccine begins with extracting white blood cells from a patient’s own blood. The cells are then treated with protein promoters that are associated with prostate cancer, which ‘tunes’ the white cells against it. Then the white cells are infused back into the patient over a three month period.

The good news, and the reasons for its approval by the U.S. Food and Drug Administration (FDA), is that it works and does not have very severe side-effects.

The less good news is that it adds at best about 4 months to the life of a patient with advanced prostate cancer. Also, a typical course of treatment costs about $93,000.

Despite that it’s a marginal improvement over existing drugs, adds a marginal improvement in life-expectancy, and costs a lot of money – it’s a first. That means, once the door has been opened – and believe me, passing through the FDA door is no mean feat – there will be many improvements to follow. As one of its proponents put it:

“The important thing about Provenge is it represents a foundation we can build on,” said Dr. Christopher Logothetis, chairman of M.D. Anderson’s department of genitourinary oncology, who testified to the FDA last year in support of Provenge. “Because its benefits now are fairly modest, it speaks to the promise of the future more than the reality of the moment.”

[Source: Houston Chronicle]

The first announcement sort of fits the battle metaphor. It’s characterized as ‘zapping nanobubbles.’ …Researchers at Rice University (Houston, USA) have developed a technique for treating cancer cells – one at a time if appropriate – by using gold nanoparticles. The nanoparticles are targeted for a specific type of cancer, where they attach to individual cells. Then a laser device, set to a specific frequency, causes the gold nanoparticles to heat causing either a (nano)bubble inside the cancer cell or exploding it (zapping).

“Single-cell targeting is one of the most touted advantages of nanomedicine, and our approach delivers on that promise with a localized effect inside an individual cell,” said Rice physicist Dmitri Lapotko, the lead researcher on the project. “The idea is to spot and treat unhealthy cells early, before a disease progresses to the point of making people extremely ill.”

[Source: EurekAlert]

The technique is not only good for an onco-shooting gallery. It can also be used for diagnosis because the nanobubbles are highly visible to microscopes. The researchers refer to this as a ‘theranostic’ opportunity – combining diagnostics followed immediately by therapy. The technique has been tested on human cancer cells. The next steps are trials of various methods of application.

The second announcement is less dramatic. It involves using nanoparticles to cross mucus barriers. That’s less dramatic, but it’s an important achievement. The human body has many organs with natural mucus barriers – the stomach, intestines, lungs, eyes, throat, cervix – some of which are nearly impermeable to traditional drug chemistry. The nanoparticles developed by the Johns Hopkins School of Medicine (Maryland, USA) have a special outer layer of polyethylene glycol (commercially, Carbowax), which makes it possible for the particles to penetrate mucus membranes with ease. The nanoparticles have been created with an inner layer of polysebacic acid, which can hold a variety of drug or genetic molecules, making the particles a drug delivery system that can be targeted for specific diseases. Better yet, the nanoparticles are designed to release their drug cargo as they biodegrade. In effect, the dissolving of the particles is the timer for release of the drugs, and when that’s over, the nanoparticle compounds are flushed out with normal bodily systems.

The original target for these nanoparticles is cystic fibrosis, which is notorious for creating unusually thick and sticky mucus in the lungs and gut.

The team’s work was reported recently in the Proceedings of the National Academy of Sciences. Hanes’ collaborators included cystic fibrosis expert Pamela Zeitlin, a professor of pediatrics at the Johns Hopkins School of Medicine and director of pediatric pulmonary medicine at the Johns Hopkins Children’s Center.

“Cystic fibrosis mucus is notoriously thick and sticky and represents a huge barrier to aerosolized drug delivery,” she said. “In our study, the nanoparticles were engineered to travel through cystic fibrosis mucus at a much greater velocity than ever before, thereby improving drug delivery. This work is critically important to moving forward with the next generation of small molecule and gene-based therapies.”

[Source: Nanotechnology Today]

This use of nanoparticles has many potential applications, some of which are in development.