22-Feb-2011 – Reducing drug side effects with nanoparticles

22-Feb-2011 – Reducing drug side effects with nanoparticles

Posted: Feb 22nd, 2011
Reducing drug side effects with nanoparticles

(Nanowerk News) Researchers at the Massachusetts Institute of Technology (MIT) and Brigham and Women’s Hospital have shown that they can deliver the cancer drug cisplatin much more effectively and safely in a form that has been encapsulated in a nanoparticle targeted to prostate tumor cells. Using the new particles, the researchers were able to successfully shrink tumors in mice, using only one-third the amount of conventional cisplatin needed to achieve the same effect. Such a dose reduction, should these results hold in human clinical trials, could help reduce cisplatin’s potentially severe side effects, which include kidney damage and nerve damage.

In 2008, this research team, headed by Stephen Lippard and Omid Farokhzad, a member of the MIT-Harvard Center of Cancer Nanotechnology Excellence (CCNE) funded by the National Cancer Institute, showed that the nanoparticles worked in cancer cells grown in a lab dish. Now that the particles have shown promise in animals, the team hopes to move on to human tests. “At each stage, it’s possible there will be new roadblocks that will come up, but you just keep trying,” says Dr. Lippard. The results of these investigations were published in the Proceedings of the National Academy of Sciences (“Targeted delivery of a cisplatin prodrug for safer and more effective prostate cancer therapy in vivo”).

Cisplatin, which doctors began using to treat cancer in the late 1970s, destroys cancer cells by damaging their DNA, which ultimately triggers cell death. Despite its adverse side effects, which also include nausea, about half of all cancer patients receiving chemotherapy are taking platinum drugs. And in addition, cisplatin suffers from other problems that ultimately limit the utility of this potent tumor-killing agent. One problem with the drug is that conventional cisplatin remains in the bloodstream for only a short period of time. In fact, only about one percent of the dose given to a patient ever reaches the tumor cells’ DNA, with about half of any given dose being excreted from the body within an hour of treatment.

To prolong the time in circulation, Drs. Lippard and Farokhzad and their collaborators decided to encase a derivative of cisplatin in a hydrophobic (water-repelling) nanoparticle. First, the researchers modified the drug, which is normally hydrophilic (water-attracting), with two hexanoic acid units — organic fragments that repel water. That modification enabled them to encapsulate the resulting prodrug — a form that is inactive until it enters a target cell — in a nanoparticle.
Using this approach, far more of the drug reaches the tumor. The researchers found that the nanoparticles circulated in the bloodstream for about 24 hours, at least 5 times longer than un-encapsulated cisplatin. They also found that it did not accumulate as much in the kidneys as conventional cisplatin, which could reduce the dose-limiting kidney toxicity that limits the duration of cisplatin treatment today. To help the nanoparticles reach their target, the researchers also coated them with molecules that bind to prostate specific membrane antigen (PSMA), a protein found on most prostate cancer cells.

After showing that nanoparticles improved ciplatin’s lifetime in the blood stream, the researchers tested their effectiveness by treating mice implanted with human prostate tumors. They found that the nanoparticles reduced tumor size as much as conventional cisplatin over 30 days, but with only 30 percent of the dose normally required to see such a therapeutic response.

The particles tested in this paper are based on the same design as particles developed by Farokhzad and his MIT colleague Robert Langer, who is the co-principal investigator of the MIT-Harvard CCNE, to more effectively deliver the cancer drug docetaxel to tumors. A Phase I clinical trial to assess those particles, run by BIND Biosciences, commenced in January. Additional animal testing is needed before the cisplatin-carrying particles can go into human clinical trials, says Farokhzad. “At the end of the day, if the development results are all promising, then we would hope to put something like this in humans within the next three years,” he says.

To view the original article CLICK HERE

I just want to say sorry for copping out at times and leaving Lee and friends to cope!
Any help and support YOU can give her will be hugely welcome.
I do make a lousy patient!

.
If YOU want to follow my fight against Cancer from when it started and I first presented with symptoms see The TAB just below the Header of this Blog. called >DIARY of Cancer< just click and it will give you a long list of the main events in chronological order.
.
Thoughts and comments will be in chronological order in the main blog and can be tracked in the >ARCHIVE< in the Right Sidebar.

You may find the TABS >MEDICAL LINKS< and also >CANCER LINKS< of help. . YOU are welcome to call me if you believe I can help in ANY way.
.

Posted by: Greg Lance-Watkins
tel: 01291 – 62 65 62

28-Aug-2011 – I do find the behaviour of the British Government shamefull

2008 August 28 03:30:37 BST
Posted By: Greg_L-W.
  Discussion
Greg_L-W.’s Blog

Hi,

I do find the behaviour of the British Government shamefull.

It is clearly revolting that on the very day the Government’s shelter organisation the QUANGO N.I.C.E. is befouling the image of what was the envy of the world, the British NHS, by hiding in their luxury Head Quarters behind their £30,000,000 annual budget.

Hiding from some 60 Kidney Cancer patients and their carers peacefully demonstrating against the new Government policy, as announced by N.I.C.E., to selectively EUthenase an entire category of patients those Challenged by Kidney Cancer who are now to be deliberately denied the drugs they clinically require both to continue to live and to have a quality in the life that is left to the,

Whilst these brave people, some of whom were dying as a result of this deliberate action, were demonstrating I, as a Kidney Cancer patient was unable to attend due to the damage I have received physically as a result of my Kidney Cancer, but whilst my friends were there to protest at their impending death, against the very people who can save them N.I.C.E. – I was aware the disingenuous claim of N.I.C.E. was that they could not afford the drugs and rather than admit it was directly due to the incompetence of the Government in the management of the Health Service – the devolved irresponsibility of regionalisation that has led to the “post code lottery”.

N.I.C.E. has even tried to shelter their incompetence to manage or negotiate, behind the specious claim that the people who researched and funded the developement of these drugs charge too much – yet it is clear that America who fund the drug for prisoners on death row and the Argentine that prescribes it more than Britain, Malasia and the EU and a total of some 70 Countries around the world would seem to disagree!

Consider – on the very day whilst my friends were demonstarting and their servants the Government funded N.I.C.E. lacked even the manners to meet with these very ill people and N.I.C.E. security was turned on these sick people to intimidate them by photographing them in the street despite the presence of Police Officers invited BY the demonstrators!

Whilst they were peacefully demonstrating and N.I.C.E. hid in shame – I read on my computer that MY Government had pledged to squander from the NHS budget £170,000,000 to train therapists to councel those with ‘Cognative Behaviour Disorder’ – to buy votes by providing this fashion and lifestyle service rather than fund the drugs that are available world wide for Kidney Cancer that may, if nothing else, provide experience for the Oncologists and researchers towards an actual cure whilst giving hope to us The Kidney Cancer Patients that N.I.C.E. have selected to deliberately permit to die for economic expediency – whilst still funding breast enhancement, In Vitro Fertilisation, tattoo removal and many other treatments that can ONLY be seen as frivolous when compared with the deliberate death of Kidney Cancer patients!

Do warn us at what stage we are to be moved into The Harold Shipman Ward in our Regionalised NHS Hospital.

First they came for Kidney Cancer patients and took away their lives

but as you were no a Kidney Cancer Patient I guess you did nothing!

Then they came for those with Crohns Disease (?) and withdrew their treatment

but as you didn't have Crohns Disease I guess you did nothing!

When they come for YOU in your hour of need and weakness –


there was no one left to help you they had been swept away, I guess 'cos you did nothing!

Where will YOU draw the line – Must it be YOUR child, YOUR Mother, YOUR wife?
Or would it have to be YOU?

That is YOUR Shame to share with N.I.C.E. and the Government that hides behind them!

Regards and Warm Hands for YOUR Hour of Need,
Greg L-W.
Available to help YOU 01291 – 62 65 62

I just want to say sorry for copping out at times and leaving Lee and friends to cope!
Any help and support YOU can give her will be hugely welcome.
I do make a lousy patient!

.
If YOU want to follow my fight against Cancer from when it started and I first presented with symptoms see The TAB just below the Header of this Blog. called >DIARY of Cancer< just click and it will give you a long list of the main events in chronological order.
.
Thoughts and comments will be in chronological order in the main blog and can be tracked in the >ARCHIVE< in the Right Sidebar. You may find the TABS >MEDICAL LINKS< and also >CANCER LINKS< of help.
.
YOU are welcome to call me if you believe I can help in ANY way.
.

Posted by: Greg Lance-Watkins
tel: 01291 – 62 65 62