Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×
Biotech Science

Gene Therapy Ages Human Cancer Cells in Lab 318

Posted by samzenpus from the my-tumor-feels-10-years-older dept.
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."
This discussion has been archived. No new comments can be posted.

Gene Therapy Ages Human Cancer Cells in Lab More

Gene Therapy Ages Human Cancer Cells in Lab

Comments Filter:

  • Finally! (Score:4, Funny)

    by Bananatree3 ( 872975 ) on Wednesday April 06, 2005 @10:34PM (#12162394)
    The perfect aging drug! Now I can look older and act younger!

  • Cool.. but some questions. (Score:4, Insightful)

    by daquake ( 307570 ) * on Wednesday April 06, 2005 @10:37PM (#12162414) Homepage Journal
    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).

    • Fertility is a big problem (Score:5, Interesting)

      by Seoulstriker ( 748895 ) on Wednesday April 06, 2005 @10:41PM (#12162446)
      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.
      • 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.

      • Re:Fertility is a big problem (Score:5, Insightful)

        by ag0ny ( 59629 ) <javi@lava[ ]ira.net ['nde' in gap]> on Wednesday April 06, 2005 @11:14PM (#12162673) Homepage
        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?
        • If you are a man you could always go down and have some of your boys frozen before you get the therapy.

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

          Isn't infertility a side effect of the current treatments such as chemo anyway?

      • Re:Fertility is a big problem (Score:5, Informative)

        by Anonymous Coward on Thursday April 07, 2005 @12:00AM (#12162951)
        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.
      • I'd say the bigger problem (other than sterility) would be affecting the telomerase inside the cells of your stomach and bone marrow (not to mention hair) which are constantly reproducing and need a certain amount of telomerase activity to replicate. Shortly after being cured of cancer you'd die of starvation. (assuming a bone marrow transplant can replace your lost marrow)
        • AFAIK the normal cells don't have telomerase activity. Their telomers are long enough to support a limited number of cell duplications, and get never rebuilt. This is the reason why they cannot multiply forever, and this again is the reason you get old and eventually die.

          However IANAB[iologist].
      • Even if the treatment causes infertility, it's still a major breaktrough -- assuming it actually works for humans offcourse.

        A pretty large part of the people getting cancer are past their having-children age anyways, or they already have all the children they want, or they don't actually want any children.

        Even if all these fail, so that the infertility is indeed a drawback, I'm sure most people would still choose alive but infertile over dead.

    • (i was just studying this)

      the /. blurb is misinformative, as telomerase is far from a "cancer-specific" enzyme. it is present in many "normal" cells, including sperm and stem cells. also, a cure would not be as simple as just injecting telomerase into a cancerous cell.

      wikipedia article [wikipedia.org]

      • Stem cells being affected is even worse (Score:4, Informative)

        by Seoulstriker ( 748895 ) on Wednesday April 06, 2005 @10:52PM (#12162539)
        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.
      • I wrote the blurb. Sorry, I understood that at the time but took it from one of the linked articles because they specifically said affectsonly cancer so thought they had something else going on to direct activity. We shall see..

    • Re:Cool.. but some questions. (Score:5, Informative)

      by Lennavan ( 847042 ) on Thursday April 07, 2005 @02:07AM (#12163412)
      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.

  • I wonder... (Score:2, Interesting)

    by wavephorm ( 838222 )
    So they can selectively age cells through gene theraphy... Can we do the inverse to stop the aging of other cells?

    • Re:I wonder... (Score:2, Funny)

      by krf ( 873528 )
      Yeah, but it actually throws the works into reverse. It's great for the first few years, but then you have to go through toilet training in reverse.

      And let's just say it goes downhill from there.

    • Re:I wonder... (Score:4, Funny)

      by Gabrill ( 556503 ) on Wednesday April 06, 2005 @10:41PM (#12162444)
      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-)

      • Re:I wonder... (Score:3, Insightful)

        by Frogbert ( 589961 )
        Unless you live in the rest of the world that isn't America, then you could purchase beer legally.

    • Re:I wonder... (Score:2, Insightful)

      by TrashGod ( 752833 )
      Can we ... stop the aging of other cells?

      Yes, but immortality is a feature of cancerous cells. That might be a Bad Idea.
      • immortality is a feature of cancerous cells

        It's only one feature of cancerous cells. Another important factor is de-regulation of the cell-cycle by degradation of critical proteins such as p53. If cells can somehow be treated for the other factors involved in cells becoming cancerous, it might be possible that expressing telomerase in all cells could eliminate the aging process. But doing so is extremely difficult and is beyond us. If we could, we would have figured out how to stop another mechanism

    • Re:I wonder... (Score:2, Informative)

      by Yotsuya ( 4378 )
      You don't want immortal cells. What you want is cells that can be regenerated. Infinitely.

  • Koreans (Score:5, Interesting)

    by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Wednesday April 06, 2005 @10:39PM (#12162427) Journal
    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.
    • And if Alex Chiu gets his way, the key to immortality


      You can already be immortal if you buy the magnets. It's the damn democrats and their public schools and culture of death that's brainwashing you into thinking they don't work.

    • Disclaimer: I'm not a biologist!
      IIRC, only human fetal research is banned. Unless humans are somehow unique, I'd bet that most mammalian life on the planet goes through the same process we do (afterall, we all look like the same little mouse at one stage, then we look like monkeys with tails, and then our tails just stop growing). Yes, eventually study on humans may be necessary for the last puzzle piece, but odds are we can put most of the puzzle together with mice, rats, dogs, cats, pigs, cows, horses,
      • afterall, we all look like the same little mouse at one stage, then we look like monkeys with tails

        "They tell us that, we lost our tails, evolving up, from little snails..."

        (Note to self: Don't post while drinking...)
    • is that the Bush administration realizes quite well that stem research could potentially create 'cure for death' and it is not good for the program to have people who are immortal. And by the program I mean the grand plan. I better shut the hell up just about now.

    • Re:Koreans (Score:5, Informative)

      by Spud Stud ( 739387 ) on Wednesday April 06, 2005 @11:17PM (#12162687)
      To be fair, fetal tissue research has not been blocked. Only federal funding thereof - privately funded research may proceed unabated.

      • Re:Koreans (Score:5, Informative)

        by nutshell42 ( 557890 ) on Thursday April 07, 2005 @06:57AM (#12164102) Journal
        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 =)

  • Telomerase not only in cancer cells... (Score:4, Interesting)

    by Necromancyr ( 602950 ) on Wednesday April 06, 2005 @10:39PM (#12162435)
    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 [wikipedia.org]

  • Go Knights! (Score:4, Funny)

    by Digitus1337 ( 671442 ) <(moc.liamtoh) (ta) (sutigid_kl)> on Wednesday April 06, 2005 @10:41PM (#12162441) Homepage
    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?

  • In normal human cells... (Score:5, Interesting)

    by racecarj ( 703239 ) on Wednesday April 06, 2005 @10:41PM (#12162449)
    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.

  • need more grant money (Score:2, Insightful)

    by qewl ( 671495 )
    This is exactly why the United States needs to donate more money to basic research. Of late science has seemed unimportant to the government, research funds have reduced and things aren't being done to provoke technologies. Instead of the government subsidizing all sorts of medications from the drug industries, there just needs to be more research towards more permanent alternatives and a reduction in patent powers. There are gene therapies for AIDS coming out and candidates for vaccines, but yet the US gov

  • Obvious question (Score:5, Insightful)

    by ChuckSchwab ( 813568 ) on Wednesday April 06, 2005 @10:47PM (#12162494) Journal
    If telomerase makes cancer cells immortal, is someone working on a way to make, uh, non-cancer cells immortal?
    • There are too many people on the freeway as it is now.

      I can just see it - carpool lanes full of 200 year old driver's - heads barely poking up above the steering wheel of her 2124 Buicks, on the way to bingo parlours, with the numbers drawn announced by actual Dick Clark(tm) clones.

    • Re:Obvious question (Score:2, Informative)

      by Anonymous Coward
      No. Making non-cancer cells immortal is not a wise idea. If you are making non-cancerous cells immortal, you are bring yourself one step closer to cancer.

      In order for a cell to become cancerous, there essentially needs to be two mutations to occur. One mutation that allows for immortality (e.g. telomerase), and one to DISregulate growth. If a cell is no longer properly inhibited (loss of a tumor repressor gene) or abnormally activated (activation of an oncogenic gene), the cell can start deviding out of co

      • Re:Obvious question (Score:3, Informative)

        by blincoln ( 592401 )
        If you are making non-cancerous cells immortal, you are bring yourself one step closer to cancer.

        The latest laboratory research into enabling telomerase in normal human cells indicates that it does not result in cancer even after the cells have lived 50% longer or more than they would have otherwise.

    • Re:Obvious question (Score:3, Informative)

      by devastopol ( 141787 )
      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 [geron.com] has.

    • That depends on what the dominent cause of aging is.

      One theory is that it is just too metabolically expensive to run a really good error checking system on non-germ-line cells.* As our cells divide, errors accumulate, more of them operate with reduced efficiency or not at all, and we see the result as aging. Fixing up the telomeres wouldn't help this.

      An analogy: Imagine when you buy a new car, you get 10 sets of extra tires. You can use those tires on your car, but not get any more. Once the 10th set is u

      • Re:Obvious question (Score:2, Insightful)

        by mr.mighty ( 162506 )
        Another theory is that it's not metabolically expensive, but that since we tend to reproduce between the ages of 15 and 35, as long as we don't die before then evolution doesn't give a crap.

        I once read a suggestion that if everyone waited to reproduce at age 40, without medical intervention, then after 3 or so generations humans would live a lot longer. Only those who managed to survive that long, and only women whose eggs managed to fight off the ravages of 40 years of life, would pass on their genes. O
    • since i don't feel like anwsering in depth, i am going to dummy down the anwser. you have something called genes. they are in every cell. they are responsible for making many different kinds of protiens needed to stay alive. often, while making protiens there are mistakes, but the human body has ways of checking and fixing these mistakes. as we get older, we lose the ability to fix these mistakes. the genes start to decay at the ends. that is why we get old and die from old age. the fix is to find ways to k

  • new todo list (Score:5, Funny)

    by hedley ( 8715 ) <hedley@pacbell.net> on Wednesday April 06, 2005 @10:50PM (#12162521) Homepage Journal
    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
    • Asbestos I can tell, that's a pretty complete list, save for the radium raves and deep tanning contests!

  • selectively? (Score:3, Interesting)

    by spamchang ( 302052 ) on Wednesday April 06, 2005 @11:03PM (#12162600) Journal
    they don't know how the gene works, they've only killed off in vitro cells, and they haven't tested it in the context of cancer cells surrounding normal cells. how can this be selective? for all we know, the mechanism could accelerate the removal of telomeres in normal cells. really, what does "selectively" mean here, besides that they selected only cancer cells to test the gene on?

    afaik, telomerase breaks down telomeres, no matter what kind of cell you have. most cancer cells inhibit telomerase to allow survival, so you'd have to inhibit the telomerase inhibitor.

    • You've got it backwards (Score:4, Insightful)

      by IdahoEv ( 195056 ) on Wednesday April 06, 2005 @11:46PM (#12162886) Homepage
      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.

  • Killing cancer is the easy part. (Score:5, Interesting)

    by zymano ( 581466 ) on Wednesday April 06, 2005 @11:08PM (#12162637)
    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.

  • Amazing... (Score:2, Funny)

    by torrents ( 827493 )
    "reported in the April 1 issue of Genes and Development"

    I just hope it's not some cruel April Fools joke...

  • Geron Turns Telomerase on/off like light switch (Score:2, Interesting)

    by Anonymous Coward
    Their TVAX vaccine against cancer in a phase one at Duke caused the strongest human immune system against cancer that has ever been seen in a cancer vaccine. 19 out of 21 men with hormone refractory prostate cancer with mets, saw thier blood become free of cancer. For some there was a thousand fold reduction in the number of blood born cells. Dr's Vieweg and Bilboa are tweaking the vaccine for the phase 2 now recruiting at Duke, see Geron's web page and click on patient info, it gives you dukes number.

  • my cousin (Score:5, Interesting)

    by ocularDeathRay ( 760450 ) on Wednesday April 06, 2005 @11:43PM (#12162862) Journal
    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.

    • Re:my cousin (Score:2, Interesting)

      by mr.mighty ( 162506 )
      I know what you mean. I had a cousin who left 5 kids when she died. My wife's mother fought it for 10 years, dying when my wife (not then) was 19. You hear about all these great advances, and wonder what took so long. On the other hand, they are going to save a lot of lives in the future.

      Look at how many people survive cancer today, though. It may be that in our lifetime, only the most advanced cases will require more than a few visits to the doctors office.
  • The only way to find a cure is to pay researchers and fund experiments to do so.

    People need your help. Here's a link to donate [kintera.org] in honor of a friend who's affected. The Cancer Walk at Tufts University is a major fundraiser for Cancer Research.

    Hope this gets modded up.

  • Obligatory (Score:3, Funny)

    by maxwell demon ( 590494 ) on Thursday April 07, 2005 @02:32AM (#12163485) Journal
    In Korea, only old cancer cells die.

  • The summary leaves out one crucial detail... (Score:3, Interesting)

    by popo ( 107611 ) on Thursday April 07, 2005 @02:36AM (#12163504) Homepage


    This experiment was conducted in a petri dish.

    Killing cancer cells in a petri dish is one thing, locating them, isolating them and killing them in the human body is another.
  • "Yea, Boss? I won't be in for the next few days. Yea, cancer. Yes, I know the project has to get done right away. Really, should be cleared up by friday. OK? Sorry about that, bye"
  • This is great! They are defeating cancer by attacking the very thing that keeps cancerous cells alive, apart from the rets of the body. This seems like the most promising path yet.

    On the other hand, might this some day offer humans immortality, by using the telomere length modulation mechanism on normal cells? I will be the first to admit I am not educated in this subject, even a little, so is this way off base?

  • Wow...predicted in scifi 7 years ago (Score:3, Interesting)

    by Snarfvs Maximvs ( 28022 ) on Thursday April 07, 2005 @10:28AM (#12165708)
    Charles Sheffield predicted this telomere therapy in his novel Aftermath back in 1998. It was later developed in the sequel Starfire to not only control cancer but to also extend life (i.e., maintaining a careful balance of telomerase to keep telomeres long enough to prevent cell death but not so long as to result in cancer).

    Additionally Alfred Bester alluded to this in The Computer Connection (1975!) where he referred to the fact that the immortals in his story were living just short of runaway cancer...sort of the theory "the cure for cancer is old age."

    Interesting how life imitates art.

  • Not first by a long shot (Score:3, Informative)

    by climb_no_fear ( 572210 ) on Thursday April 07, 2005 @10:40AM (#12165829)
    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 [nature.com]

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

Slashdot Top Deals

"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." -- Bertrand Russell

Close