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Gene Therapy Ages Human Cancer Cells in Lab

mattr writes "Korean scientists are the first in the world to selectively age off and kill human cancer cells, by injecting a gene that suppresses telomerase, a cancer-specific enzyme that normally makes cancer cells immortal by protecting the telomere tips of their chromosomes. The telomere length modulation mechanism was found by two scientists from Yonsei University and colleagues at U. Central Florida, and is reported in the April 1 issue of Genes and Development magazine."

32 of 318 comments (clear)

  1. Finally! by Bananatree3 · · Score: 4, Funny

    The perfect aging drug! Now I can look older and act younger!

    1. Re:Finally! by shadowbearer · · Score: 4, Funny

      Don't worry, that comes with time ;-)

      SB

      --
      It's old. The more humans I meet, the more I like my cats. At least they are honest.
  2. Cool.. but some questions. by daquake · · Score: 4, Insightful

    This is incredible in theory, but what time frame are we talking about in humans once this gene is injected? Will it adversely affect human cells? I read it targets a cancer specific enzyme but am I missing anything? Could this be a cure, after the fact? (Bio-Medical newbie here).

    --
    Be True, Unbeliever
    1. Re:Cool.. but some questions. by Lennavan · · Score: 5, Informative

      I honestly hope some moderator mods this up fast. I'm a grad student working on this very thing so I'd like to hope I know something about it... When Dolly was first cloned we all thought telomeres were the key to keeping clones alive longer. So when Dolly was made as a clone the nucleus was injected into an oocyte that had telomerase activity that restored Dolly's telomeres (read: Dolly had normal telomeres). Yet Dolly displayed many diseases and phenotypes that old sheep normally would. The obvious conclusion, there are other factors that we don't know about that contribute to both aging and death. Please please please don't think telomerase is the key to immortality and the cure to cancers. Yes most cancers eventually gain telomerase activity but this isn't some magical target for immortality and cancer cures.

  3. Koreans by Dancin_Santa · · Score: 5, Interesting

    In Korea, only cancer gets old!

    But seriously, this is very interesting. When telomeres started getting press a few years back, it was really obvious that this would eventually be the key to managing cancer. (And if Alex Chiu gets his way, the key to immortality).

    If cells age because child cells of a mitosified cell contain fewer telomeres, then something that prevented that telomeric loss would lead to an eternal lifetime for splitting cells.

    What has interested me about this is that babies are born with a full set of telomeres. This means that the telomeric levels of the parent (mother) is not passed to the child. All other cells in a person's body are dependent on the number of telomeres present in those first few cells clumped together in the womb.

    By blocking fetal tissue research, the harvesting of these precious cells is hampered. The reasons for fetal research are many, and the study of telomeres is one big area that simply can't be replicated with non-fetal stem cells.

    1. Re:Koreans by Spud+Stud · · Score: 5, Informative

      To be fair, fetal tissue research has not been blocked. Only federal funding thereof - privately funded research may proceed unabated.

    2. Re:Koreans by Anonymous Coward · · Score: 4, Informative

      Cancer cells turn on the genes full-tilt for Telomerase, ensuring their survival. Normal, healthy cells do not and eventually die -- it is believed to be a protection AGAINST cells becoming cancerous. That is, if a cell lives long enough it will eventually accumulate enough gene damage that it stops working correctly and likely becomes cancerous.

      That is not to say that turning on telomerase in healthy cells is a bad thing -- as long as you have a way to turn it off in cancerous cells. If one could do that, then yes, the normal cells could be for all intents and purposes considered immortal.

    3. Re:Koreans by nutshell42 · · Score: 4, Informative
      The problem is that afaik it's impossible for an *institution* to get federal funding if anyone of that institution does such research.

      So you don't lose federal funding for a specific project but for everything. With very few exceptions almost any university, research institute etc. gets federal funding for something (could be the sports program, cleaning the toilets, other research projects...) so effectively it's a ban.

      Feel free to correct me if I'm wrong (and you have proof =)

      --
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  4. Telomerase not only in cancer cells... by Necromancyr · · Score: 3, Interesting

    Telomerase is not only in cancer cells, it's in a bunch of other kind of cells - generally ones long lasting. That's what gave the idea in the first place to do research along these lines. The Wikipedia isn't totally off, would be a good thing to read for correct information: http://en.wikipedia.org/wiki/Telomerase

  5. Go Knights! by Digitus1337 · · Score: 4, Funny

    The University of Central Florida doesn't get any credit because we don't have a good football team, but this is the third /. piece featuring the school in the past six months. How's for some nerd credit?

  6. Re:I wonder... by Gabrill · · Score: 3, Funny
    You missed the point where they had to inject each cell to target it. If we just uniformly make all cells immortal, then we would have out of control cell reproduction. You know, kind of like cancer.

    The real trick would be to figure out how to hold the human body at the point of equilibrium for 18 to 21 years of age.

    Never mind that. Then we couldn't legally get beer. 8-)

    --
    Always going forward, 'cause we can't find reverse.
  7. Fertility is a big problem by Seoulstriker · · Score: 5, Interesting

    Inhibiting telomerase has a significant problem: it kills off the gametocytes, which need telomerase to reproduce constantly but still have constant length telomeres. The side effect has to be infertility, unless the researchers found a receptor or variation in cancer cells which allows selective target for the vector. I have a feeling that it is not what they did, since the cancer cells were grown in a tissue culture, and not in vivo. We'll have to wait for human studies to see where this is going.

    This mechanism has been studied for a very long time, but this must be the first time that researchers have been successful in manufacturing the vectors.

    Of course, there are still promising treatments such as angiogenesis inhibitors which has the benefit of not losing fertility.

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    1. Re:Fertility is a big problem by pmazer · · Score: 3, Insightful

      I think loosing fertility is a suitable side-effect for most people with cancer. If this works 100% or at least if you can tell if it will work or if it won't, then most people will be happy to give up their fertility in exchange for ridding their body of a potentially deadly enzyme. Also, this will be a wonder drug for seniors, who could most likely care less about fertility and who chemotherapy will make incredibly weak and not worth living.

    2. Re:Fertility is a big problem by ag0ny · · Score: 4, Insightful

      Infertility is also a side-effect of, well, being dead because of cancer.

      If you were given the choice between being alive but infertile or being dead, which one would you choose?

    3. Re:Fertility is a big problem by Anonymous Coward · · Score: 5, Informative

      I think the real problem is the insertion of this gene into cells in general. Unless the technique is 100% efficient (all the cancer cells are treated), the tumor is going to just grow back again.

      Using a virus to infect cells wouldn't work because any further doses of the virus would be less effective due to immune responses. Even when just using liposomes (spherical containers made up of phospholipids) carrying the antitelomerase gene to transfect the cancer cells, the efficiency would only be about 50% max. This means that only 50% of the cells would get the gene, while the remaining will still be untreated. In this situation, the transfected cells will die off due to the effect of this new anti-telomerase gene, but the untransfected ones will have a selective advantage and take over, making the tumor continue to grow.

  8. In normal human cells... by racecarj · · Score: 5, Interesting

    What isn't clearly mentioned is that telomerase is *inactive* in normal human cells. We're born with our telomeres at a certain length, and they're never renewed. That's why some cancers are unique in that they reactivate this latent gene therebye making them immortal; for example, Hela cells are used in every lab across the country. They originally were taken out of some woman's breast cancer in the 50's and they're still thriving! As a matter of fact, while she's long dead, there's still several tons of her! But even if you were to turn off a reactivated telomerase gene, it is logical to believe that they would begin to age normally; ie, if the person with the cancer is in his 50's, the cancer might not die for several decades. The important thing to remember is that *every* cancer in every person is different on a molecular level. They are all unique, and that is why we'll never have a blanket cure for cancer. What we will eventually have is effective treatment for currently untreatable types, which is a different story all together.

  9. Re:who gets credit by shigelojoe · · Score: 3, Funny

    Do you have any proof of this or are you just talking out your ass?

    You must be new here.

  10. Re:who gets credit by deathcloset · · Score: 3, Insightful

    well, are you going to forget? I'm not.

    so long as we remember and make sure to cite and post what we remember and write articles for wikipedia on what we remember then such things will not be forgotten or overlooked.

    these days "they" are less and less often the media and the journals.

    "They" is becomming "us", and I love it.

  11. Re:I wonder... by DarkMantle · · Score: 4, Funny

    but then you have to go through toilet training in reverse.

    This happens anyway. Haven't you heard of adult diapers?

    --
    DarkMantle I been bored, so I started a blog.
  12. Obvious question by ChuckSchwab · · Score: 5, Insightful

    If telomerase makes cancer cells immortal, is someone working on a way to make, uh, non-cancer cells immortal?

    1. Re:Obvious question by devastopol · · Score: 3, Informative
      If telomerase makes cancer cells immortal, is someone working on a way to make, uh, non-cancer cells immortal?

      Yes, to some degree, Geron Corporation has.

  13. new todo list by hedley · · Score: 4, Funny

    1) Eat more charred foods
    2) Use the cell phone handset a lot more
    3) picnic under high tension wires often
    4) cheap cigarettes from Canada
    5) Use more liquids ending in -ene, -ide
    6) Have more food colouring parties
    7) Break out that Roentgen tube lying in the attic, make some cool photos.
    8) Work with small fibres and dusts as often as possible.

    Yep, now I can really break loose...

    Hedley

  14. Stem cells being affected is even worse by Seoulstriker · · Score: 3, Informative

    If bone marrow stem cells are also affected by this treatment, you can have problems with production of T-cells (CD4+ and CD8+) and erythrocytes (red blood cells). I wish that they would have at least done tests on other types of human cells. The journal article becomes available April 15th, so we shall see what all the fuss is about.

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  15. Killing cancer is the easy part. by zymano · · Score: 4, Interesting

    Finding it and then inserting genes or drugs to kill it is hard.

    Gene therapy using viruses has failed because the body attacks the modified virus . Some people have died because of this and research was stopped.

    There are some new ideas on using HIV virus which is harder for the immune system to attack.

  16. Re:who gets credit by Anonymous Coward · · Score: 5, Insightful

    I know it sounds very progressive to make those sort of assertions, but they don't have much merit. Anyone with even a rudimentary scientific background will tell you that key scientific breakthroughs come from all over. As a matter of fact, in the past few years there has been a considerable amount of concern within the American scientific community over the lag in American research and publication. Research just isn't a priority anymore in America, and we are beginning to feel the effect.

    My guess is that the Korean scientists will keep their credit, just like the Koreans scientists who recently successfully generated stem cells from somatic adult tissues, just like the Dutchman who came up with the microscope, just like the Moravian monk who counted peas, just like the Swede Botanist retained credit for the Linnaean classification, just like the Russian Chemist retained credit for the periodic table, just like 10th century Arabs retained credit for much of Algebra, just like citizens of Greek city-states retain credit for beginning to formalize reason.

    The capacity for human genius is universal, and in the reality based community known as science, we appreciate that. It belittles the intellects of foreign researchers and the hard work of American scientists to say otherwise.

  17. my cousin by ocularDeathRay · · Score: 5, Interesting

    wow. I am glad to see some good news like this. I have a cousin dying of leukemia(sp?) who probably won't live through the weekend. She is 37 yrs old. she has 4 kids... the younger ones are 2 and 4.

    At times like this it is hard not to get mad at the medical profession. On the other hand I have a great appreciation for what medicine has done for my family.

    The cousin I mentioned got an extra year of life because of an experimental stem cell (no not the kind thats been in the news) transplant.

    My father has had open heart surgery twice. He is 64 years old and still goes backpacking with my brother and I.

    My mom, although a survivor has had cancer 3 seperate times: breast cancer in each breast and a melanoma in her eye.

    It is from the latter that I gained a great respect for medical research, and it is why I smile reading a story like this article.

    when she had her eye cancer there was a new experimental treatment at the UW hospital here in seattle. They cut her eye open and sewed a patch of radioactive material over the tumor. They then sewed the eye shut and sent her home for several days with a lead shield over her eye.

    Then they took her back to the hospital and cut the eye open again and removed the patch. Over the course of the next year the tumor died back (we know because of the ultrasound and other tests they do on her). Now she has finally lost the last of the usefull sight in that eye. The sight-loss is due to the close proximity of the radiation treatment to the optic nerve.

    The only other treatment at the time was to remove the eye completely. With the radiation treatment she got many years of good sight out of that eye she wouldn't have had.

    It is funny to me that at the time that treatment seemed so high tech. now it just sounds barbaric. cutting the eye open twice... so invasive. Now this article highlights something that may, in our lifetime be the new exciting experimental cancer treatment, and our kids (if they can still afford health care) will wonder how we endured such brutal treatment (I would suspect no cancer treatment in our lifetime will be FUN anyway)

    I guess my cousin's situation has me in an extra thoughtful mood tonight.

    --
    Obama is a twitter sock puppet
  18. You've got it backwards by IdahoEv · · Score: 3, Insightful

    afaik, telomerase breaks down telomeres, no matter what kind of cell you have.

    That's upside-down. Telomeres automatically shorten themselves with every cell division. Cells with very short telomeres die. This acts to limit cell divison, and probably exists (among other reasons) to limit runaway growth like cancer. Telomerase is not involved in this process at all, and in fact is not present in most normal cells.

    Telomerase acts to lengthen telomeres so that the cells in question can keep dividing. Telomerase exists likely so that cell which do need to divide forever (like germ cells and bone marrow cells) can overcome the telomere limit imposed on the rest of the body.

    afaik, telomerase breaks down telomeres, no matter what kind of cell you have.

    Again, that's backwards. Most cancer cells express telomerase where the normal cell wouldn't. This lengthens the telomeres and allows cell division to continue.

    Thus, inhibiting telomerase will re-impose the division limit on cancer cells, suppressing tumor growth. That's what this study claims to do.

    Summary:

    Telomere: passive cancer suppressor/division limiter present in every cell.

    Telomerase: enzyme to allow a few special-case cells to keep dividing despite telomeres.

    Cancer: often turns on telomerase in cell types where it should be dormant.

    --
    I stole this sig from someone cleverer than me.
    1. Re:You've got it backwards by IdahoEv · · Score: 3, Informative

      Oops - second quote should have been:

      most cancer cells inhibit telomerase to allow survival, so you'd have to inhibit the telomerase inhibitor.

      --
      I stole this sig from someone cleverer than me.
  19. Re:who gets credit by Desert+Raven · · Score: 5, Funny

    Yup, I can see it now:

    Aide: Sir, have you looked at the bill on genetic research?

    Shrub: Yes, and I vetoed it.

    Aide: Um, why sir? It would have cured cancer?

    Shrub: It said a side-effect of the research might be immorality, and I won't STAND for that!

    Aide: (slaps forehead) No sir, it didn't say immorality, it said immortality.

    Shrub: (looks confused)

  20. Re:who gets credit by Clay+Pigeon+-TPF-VS- · · Score: 3, Funny

    I beg to differ. He gets modded down for not following group think, but he does come up with some good stuff.

    --
    Viral software licensing is not freedom, it is in fact GNU/Socialism.
  21. Re:Not always.... by penguin+king · · Score: 4, Informative

    Who was it that revolutionised the dye industry? The Americans and Germans? I'm sorry I was of the impression that an Englishman by the name (Sir) William Perkins revolutionised the dye industry. The first non-plant based die, based on coal-tar analine products was discovered by Sir William. The first such die was Mauve, this discovery of how to manipulate organic products is generally recognised as one of the discoveries that revolutionised modern chemistry, drugs etc which you credit to America and Germany. Interesting that you use American spellings, so I presume you are American yourself.

    Sure it would be true to say that other countries took the revolution and made the most of it, the revolution itself, and the start of such industrial manufacturing of dies(leading onto other related areas) started in the house of William Perkins, in London England.

    William Perkins

    Also a good read:

    Mauve

  22. Not first by a long shot by climb_no_fear · · Score: 3, Informative

    Here's a 4 year old paper about a compound that doesn't only work in cell culture but also in animals. Sorry but who's first?

    A highly selective telomerase inhibitor limiting human cancer cell proliferation

    As an aside, would you rather take a pill or inefficient, potentially mutagenic gene therapy?
    I know what I'd choose...