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Medicine Science

Using Nanoparticles To Improve Chemotherapy 35

Posted by Unknown Lamer
from the or-give-walter-skinner-a-heart-attack dept.
sciencehabit writes with good news involving cancer research. From the article: "Chemotherapy drugs are like a shotgun. Even though doctors are just aiming for tumors, the compounds hit a variety of other places in the body, leading to side effects like bone marrow damage and hair loss. To improve their aim, researchers have tried to package these drugs inside tiny hollow nano-sized containers that can be directed toward tumors and bypass healthy tissues. But the size, shape, and makeup of these 'nanoparticles' can drastically affect where and when they are taken up. Now, scientists have surveyed the landscape of some 100 different nanoparticle formulations and shown that when a conventional chemotherapeutic drug is packaged inside the best of these nanoparticles, it proves considerably more effective at fighting prostate cancer (summary; article paywalled) in animals than the drug alone."
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Using Nanoparticles To Improve Chemotherapy

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  • by nimbius (983462) on Friday April 06, 2012 @01:02PM (#39598987) Homepage
    instead of correlating cancer to things like BPE and other refined petrochemical bioaccumulants as well as using science to determine threatining chemicals in our endless consumer-driven product lines, we're just ignoring these or calling them 'cancer-suspect agents' or redefining the PEL to be met under laughably unrealistic conditions in the real world?

    id make a cursory assertion that the lock-step rise in cancer rates is probably related somehow to the twin revolving-doors of the EPA and FDA, through which industry experts and regulators are frankly indistinguishable and utterly useless.
    • Re: (Score:2, Interesting)

      by Anonymous Coward

      Yes, let's totally abandon all the conveniences of modern life due to slight possible health risks.
      How about birth control pills?

      http://en.wikipedia.org/wiki/Birth_control_pill#Environmental_impact

      Love the greens and their nostalgia for a simpler time when we all lived short agricultural subsistence living life spans.

      Nothing like actually working an organic subsistence farm on a commune to find this stuff pretty laughable.

      • I don't think he wants to go back to the stone age, but the EPA and FDA flounder around regularly. They are understaffed for what they are expected to do, and like all politics it's a farce anyway. No ones required to tell you what they've done to the food they sell you, and the drugs on the market now-a-days carry more side affects than cures.
        • by doston (2372830)

          I don't think he wants to go back to the stone age, but the EPA and FDA flounder around regularly. They are understaffed for what they are expected to do, and like all politics it's a farce anyway. No ones required to tell you what they've done to the food they sell you, and the drugs on the market now-a-days carry more side affects than cures.

          So we've got security theater, regulatory theater and probably cancer research theater, too, since I still, in 2012, walk around the local co-op and regularly see bald, pale cancer patients even after years of reading about wonderous new cancer discoveries. Remember that two statin combo that cured *all* forms of cancer (in mice) in the late 90s or early 2000s? Part of me thinks they'll never cure it and the whole point of all this is just to create "hope" so money will continue to pour in and researchers

      • Not to mention that there are estimates that about 80% of these studies cannot be reproduced.

        Including the BPA ones.

        http://toxsci.oxfordjournals.org/content/114/1/1.full [oxfordjournals.org]

        While it's fine to be conservative when considering the impact of adding something to the food chain, we need to also consider these studies with a very jaundiced eye. The simple fact of this matter is that in the worst case scenarios, i.e. occupational exposure (workers at the actual factories that make this stuff) there is no epidemiologic

    • by Anonymous Coward

      I'd be more concerned about overall dose of radiation. Did you know that airline crews receive a higher dose of radiation than any other profession? Even working in a nuclear power plant exposes you to less ionizing radiation (assuming you aren't in one that you know, blows up, melts down, etc). Cancer is caused by dna mutation, ionizing radiation is good at that. Every single living thing is exposed to some level of ionizing radiation. Even if that level is "safe" any increase will increase your odds

      • Re: (Score:2, Interesting)

        by Anonymous Coward

        Actually, radiation exposure is not linear.

        Low levels are easily handled by the body since we've evolved to deal with low levels.

        In fact, there is evidence that low but slightly elevated levels may have a protective effect, due to hormesis.

        • by Anonymous Coward on Friday April 06, 2012 @02:19PM (#39599971)

          What you are saying is valid but does not relate to radiation causing cancer. It relates to say, radiation flat out killing you from destroying your body's critical tissue faster than it can regenerate and keep you alive (say, membrane of the lungs for instance, lining of the stomach or intestines, etc). You can be exposed to tons of radiation but never get a random cancer causing dnamutation, or you could be exposed to only normal radiation and get a random cancer causing dna mutation. Sorta like how a person can be shot 10 times and live (say arms legs shoulders no vital organs or arteries), but a person shot in the head has a tendency to die. While it only takes one, statistically speaking bullets are bad for your body (each has a statistical chance of being a critical hit, the more hits = greater overall chance). Roll a 6 sided die, if you roll one you die, 1 in 6 right odds right? Now roll 2, if either one rolls a 1 you die, now 3... your chances increases as the number of rolls increases.

          Radiation causes many different types of mutation. Some of its good (drives evolution for instance), some isn't good but not particularly harmful (breaks cell wall, cell dies, meh, cells die all the time). In those cases radiation exposure damage isn't linear, your body is able to cope with so much as a time.

          But Cancer is different. Cellular damage from radiation isn't particularly rare, but among that mutation is somewhat rare (speaking lots of ionizing incidents and lots of cells in a body here, so bear with the definition of "rare"). Cancer is a RARE form (or forms if you will) of mutation which causes a cells otherwise limited reproductive (splitting) cycle to become unlimited.

          Normally when DNS strands split they lose a Telomere, eventually the splits run out of telomeres. In the case of say skin which replenishes all your life, a adult stem cell from your bone marrow enters your blood stream, it becomes the "first" skin cell of this splitting process, it will then over time split about 20-30ish times to produce a whole lotta cells. If the Telomere chain didn't get shorter, this would go on for ever, ie, you'd get a lump that grew larger and larger and larger.

          A little bit of cancer isn't good for you due to the "grows forever" thing.

          • by Anonymous Coward

            I was responding specifically to radiation causing cancer.

            http://en.wikipedia.org/wiki/Radiation_hormesis [wikipedia.org]

            "Proponents of radiation hormesis typically claim that radio-protective responses in cells and the immune system not only counter the harmful effects of radiation but additionally act to inhibit spontaneous cancer not related to radiation exposure."

            Note I didn't say that it was proven either.

            They go on to outline a growing body of research that illustrates that the human body is not a passive accumulator

    • by mcgrew (92797) * on Friday April 06, 2012 @02:43PM (#39600307) Homepage Journal

      id make a cursory assertion that the lock-step rise in cancer rates is probably related somehow to the twin revolving-doors of the EPA and FDA

      You woudn't if you'd been alive before the Clean Air Act and the Clean Water Act like I was. The difference between now and 1969 is incredible, especially around factories.

      Back then, when cars didn't have air conditioning, you had to have the windows rolled up when driving past a Monsanto plant because the air literally burned your lungs and made your eyes water. What little vegetation there was anywhere near these plants was brown and sickly. Now drive past a Monsanto plant and you might catch a whiff of bleach at worst, and usually smell nothing at all, and there's now healthy green vegetation.

      Before the EPA, rivers and streams were so polluted that they actually caught fire.

      This graph (PDF) [ucsd.edu] shows cancer rates between 1930 and 2000. There's a slow rise in lung cancers from 1930 to the late 1940s, when they rose far faster until around 1990 when they started dropping. It makes me suspect radiation is the primary culprit, since above ground atom bomb testing started in the mid '40s and stopped in the 1960s.

      Your primary source of chemical carcinogens (you being a desk-bound nerd as opposed to someone working at Monsanto) is probably your automobile. Both the fumes from the gasoline and the exhaust from your tailpipe are highly carcinogenic.

      I googled BPE and found no chemical with that name.

      .500 Black Powder Express
      Bachelor of Physical Education
      Ballpark estimate
      Banco Popular Español, banking group in Spain
      Barclays Private Equity
      Bataan Provincial Expressway in the Philippines
      Before Present Era - a year numbering system often used in archaeology in which the year 1950 is used as the epoch marker, an alternative to Before Present.
      Berliner Parkeisenbahn, a ridable miniature railway near Berlin Wuhlheide station
      Bureau of Public Enterprises in Nigeria
      Byte pair encoding in computing
      Spanish ship Juan Carlos I (L61), initially known as Buque de ProyecciÃn Estratégica

      I doubt you were referring to Byte Pair Encoding. The chemical that makes plastic stiff maybe? I can't remember what the stuff is called.

      • by treeves (963993)

        Probably meant BPA (bisphenol-A) . Monomer used to make polycarbonate (the plastic that CDs and some bottles and other things are made of.)
        I think it's blamed for a lot of things and many places are banning it, don't know how much of that blame is correctly placed.

      • by asher09 (1684758)
        BPE = biphenyl ether
        Their derivatives are used in plastics and as flame retardants in many different products. They're super common. Sorry no citation. I'm an organic chemist that have worked with those chemicals
      • by Guppy (12314)

        That's pretty much the situation they have in some parts of China today (although supposedly it's getting better, slowly). They actually have pretty good environmental protection laws on the books, but the environmental ministry itself has relatively little power -- so enforcement tends to be at the whim of the wealthy and powerful, depending on whether it is benefiting or costing them in any particular situation.

  • Diamond Age?

    This is cool

  • Didn't we just get a big article about how cancer related publications are not trustworthy? Why do we trust this one?

  • At least- that is what we'll find next week.
  • by Anonymous Coward

    At poisoning the kidney and liver. Nanoparticles were never meant as a drug delivery system, but a tumor indication drug, perhaps with a nuclear tag. Most of them get caught in the liver and kidneys, and if they are filled with poison, they'll cause a lot of trouble.

    • by reverseengineer (580922) on Friday April 06, 2012 @02:05PM (#39599795)
      Depends on what the material of the nanoparticles is. The PEG-PLA system used in this study doesn't tend to accumulate, and in fact the lactic acid from the breakdown of PLA can be metabolized. Similarly, the drug Abraxane, already on the market, uses nanoparticles of human serum albumin. In terms of the liver and kidneys getting exposed to the released drug, yes, that is a hazard, but one that exists regardless of the delivery method. Using nanoparticles can greatly increase the solubility and bioavailability of many drugs so that less can be used.
  • Prostate cancer tends to strike late in life and is very slow growing. It is so unlikely to kill that there has been considerable debate on whether it makes sense to screen for it. On average, the treatment is worse than the disease. Left untreated, victims usually live long enough to die from other things before the cancer can become a problem.

    • There has been some research into the use of nanoparticle delivery systems for treatment of glioblastoma multiforme, a brain tumor which is often both aggressive and difficult to treat conventionally. Here is an example [nih.gov] that met with some success.
  • I wonder where they find animals with prostate cancer. Is there a farm/factory where rats with prostate cancer are produced? Do they inject cancer cells into the rats/dogs/pigs/whatever to simulate cancer? If so, how can anyone be sure that artificially induced cancer will react the same as homegrown cancer? Next Dear Google, I think.
    • by samazon (2601193)
      In case anyone was curious:

      Cancer is induced in lab animals by injecting chemical compounds. I presume that they inject directly into whatever organ they want to study (prostate, liver, etc).

      Unregulated cellular grown due to genetic abnormality/mutation (cancer) - is differentiated based on location and a slew of other things. Apparently, when your cells are mutating, you can lose an entire chromosome. Neat, huh? So it's just killing all the mutated genes and hoping that no more mutate. Leads me to

  • From the article: The nanoparticles are made from cyclodextrins coated with PEG that contain as cargo the anticancer compound camptothecin. The selectivity is apparently not due to the selective uptake of nanoparticles by cancer cells but rather that the interior of cancer cells are more acidic than normal cells. After cells takes up nanoparticles, the nanoparticle breakdown releasing the camptothecin. Because of the lower pH, the break down occurs faster in cancer compared to normal cells.
  • A similar technology is a significant portion of the reason why my father is alive today.

    They're called SIR Spheres and they can be used to carry chemotherapy drugs or a radioactive isotope.

    In my fathers case, they used Yttrium-90 to treat the cancer that originated in his gall bladder and had spread into his liver. They allow for a very directed method for delivery of the chemo or radiation.

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