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Treatments: Should Cancer Stem-Cells BeTheFocus?

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General fitness, health and nutrition
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5 May 2004
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11 May 2004
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su-texas
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  1. google.comsearch

    From what I just read, the currect cancer treatments might
    be the wrong approach, because they don't target cancer
    stem-cells.

    I was reading about cDNA, gene-chips, & cancer.

    Susan, Su_Texas my opinions

  2. (IMO stem cells are what Beard describes as the germ cells
    in trophoblast thesis of cancer) There was a recent article
    on stem cells and Beard's thesis in New Scientist - you
    might want to try chasing it up. www.newscientist.com Basic
    theory is that cancer is a placenta (The theory still stands
    up to scrutiny today - this doesn't mean it is right!). In
    pregnancy at (56 days *I think*?) the babies pancreas
    becomes active and it starts pumping out proteolytic enzymes
    trypsin/chymotrypsin. These enzymes kill the invasive cells
    of the placenta and stop it from growing/invading the
    mother. Anth

    <[email hidden]> wrote in message news:12914-40990CD5-119@storefull-
    3195.bay.webtv.net...

    Quoted message said:

    google.comsearch

    From what I just read, the currect cancer treatments might
    be the wrong approach, because they don't target cancer
    stem-cells.

    I was reading about cDNA, gene-chips, & cancer.

    Susan, Su_Texas my opinions

  3. U-M scientists find "stem cells" in human breast cancer =A0
    Discovery could explain current treatment failures, and lead
    to more effective therapies for many cancers: added 02/24/03

    ANN ARBOR, Mich. - Of all the neoplastic cells in human
    breast cancers, only a small minority - perhaps as few as
    one in 100 - appear to be capable of forming new malignant
    tumors, according to just-published research by scientists
    in the University of Michigan Comprehensive Cancer Center.

    The discovery could help researchers zero in on the most
    dangerous cancer cells, to develop new more-effective
    treatments.

    "These tumor-inducing cells have many of the properties of
    stem cells," says Michael Clarke, M.D., a U-M professor of
    internal medicine, who directed the study. "They make copies
    of themselves - a process called self-renewal - and produce
    all the other kinds of cells in the original tumor."

    Although similar cells have been identified in human
    leukemia, these are the first to be found in solid tumors,
    Clarke adds.

    The cells were isolated from primary or metastatic breast
    cancers, removed from nine women treated for cancer at the
    U-M's Cancer Center.

    The discovery - reported this week in the online early
    edition of the Proceedings of the National Academy of
    Sciences - also may explain why current treatments for
    metastatic breast cancer often fail, says Max S. Wicha,
    M.D., an oncologist and director of the U-M Comprehensive
    Cancer Center.

    "The goal of all our existing therapies has been to kill as
    many cells within the tumor as possible," Wicha says. "This
    study suggests that the current model may not be getting us
    anywhere, because we have been targeting the wrong cells
    with the wrong treatments. Instead, we need to develop drugs
    targeted at the tumor's stem cells. If we are to have any
    real cures in advanced breast cancer, it will be absolutely
    necessary to eliminate these cells.

    "What this means for women with cancer is that, for the
    first time, we can define what we believe are the important
    cells - the cells which determine whether the cancer will
    come back or be cured," Wicha adds. "Before this, we didn't
    even know there were such cells."

    All cancer cells have a unique pattern of proteins, similar
    to a fingerprint, on their surface membranes, explains
    Muhammad Al-Hajj, Ph.D., a U-M post-doctoral fellow and
    first author of the PNAS paper. " We used specific
    antibodies and flow cytometry technology, to segregate the
    phenotypically heterogenous cancer cells within a tumor,
    into isolated populations based on their surface protein
    markers," Al-Hajj says.

    These isolated cell populations were then individually
    injected into immune-deficient mice, and the mice were
    examined for tumor growth every week for up to six months.

    Al-Hajj found [that] a small group of cells, with a
    phenotype common to all but one of the human tumors in the
    study, could form new cancers in
    mice. These cells all expressed a protein marker called
    CD44, in addition to having either very low levels or
    no levels of a marker called CD24.

    "As few as 100 to 200 of these tumor-inducing cells,
    isolated from eight of nine tumors in the study, easily
    formed tumors in mice, while tens of thousands of the other
    cancer cells from the original tumor failed to do so,"
    Clarke says.

    The fact that tumor-inducing stem cells from eight of nine
    women, showed a common surface marker pattern is
    significant, Wicha explains. "Even though it's only nine
    patients, it shows that the markers identifying these stem
    cells, were expressed in the majority of breast cancer
    patients in the study. This may not be the only expression
    pattern on every patient's stem cells, but it demonstrates
    the validity of the cancer stem cell model."

    To test the stem cell's ability to regenerate the
    original tumor, U-M scientists repeated the experiment up
    to four times.

    First, 200 cells with the unique two-marker surface pattern,
    were isolated from the original human tumor. When these
    cells produced a breast tumor in a mouse, Al-Hajj removed
    the mouse tumor, and used flow cytometry to isolate 200 stem
    cells from it. These cells were then injected into another
    mouse to produce another tumor. Once again, the tumor was
    harvested, stem cells were separated, and injected into
    another mouse. Each procedure is called a passage.

    "Tumor cells with this particular surface marker pattern,
    produced a new tumor in the next generation of mouse every
    time," Clarke explains. "When we examined the tumors after
    each passage, we found their cell diversity to be the same
    as the original tumor."

    Given that tumor-inducing cells now have been identified in
    breast and blood cancers, Wicha and Clarke believe it is
    likely that similar cells drive the development of other
    types of cancer, as well.

    The U-M Comprehensive Cancer Center is establishing a new
    research program, to identify stem cells in other cancers
    and develop new therapies to destroy them.

    "What we are working on now, is finding out what makes these
    tumor stem cells different from the other cells in a tumor,"
    Wicha says. "Now that we can actually identify them, we can
    start developing treatments to specifically target and
    hopefully eliminate them."

    "This is not a cure for cancer," Clarke emphasizes. "But it
    is a very promising lead, which will focus our efforts to
    try to find a cure for cancer."

    In addition to Al-Hajj, Wicha and Clarke, Sean J. Morrison,
    Ph.D., a Howard Hughes Medical Institute assistant
    investigator and U-M assistant professor of internal
    medicine, is a collaborator in the research study. The U-M
    study was funded by the National Cancer Institute.

    The U-M has applied for a patent on the identity and
    function of tumor stem cells.

    Special notes on this release:

    Though promising, this research is still in the animal
    testing stage.

    Additional research will be needed, before this research
    progresses to the point, where it could benefit breast
    cancer patients.

    ["]http://www.cancer.med.umich.edu/news/stemcell.htm]

    ----------------

    Susan, Su_Texas my opinions

  4. ["]http://www.genomenewsnetwork.org/articles/03_03/stem_c.shtml]

    The Real Problem in Breast Tumors: Cancer Stem Cells=A0=A0By
    Nancy Touchette, March 7, 2003

    The quest for a cancer cure seems like the ending to a Kafka
    novel: so close, yet so far away. Decades of research and
    billions of dollars in funding have revealed much about the
    molecular events that lead to cancer. But overall, today's
    cancer cure rates are not much better than they were 30
    years ago.

    Part of the problem, a new study suggests, is that current
    cancer therapies may be targeting the wrong cells. The real
    issue may be a small population of cells in tumors that
    resemble adult stem cells (the self-replicating cells that
    give rise to specialized cells in tissues).

    Michael F. Clarke and Max S. Wicha, and their colleagues at
    the University of Michigan in Ann Arbor, have identified a
    small population of cells in breast tumors, that can seed
    the growth of new cancers. These cancer-causing cells, which
    make up a tiny fraction of cells within tumors, have
    properties similar to those of stem cells.

    "This study creates a whole new conceptual paradigm, of how
    tumors form," says Robert A. Weinberg of the Whitehead
    Institute for Biomedical Research, an early pioneer in the
    study of cancer-causing genes. "It changes our thinking."

    Researchers have traditionally thought of cancer, as a
    collection of cells all growing exponentially. "This paper
    demonstrates convincingly, that the model is wrong," says
    Weinberg. "Only a few cells are endowed with the ability to
    replicate. It has profound implications, for how we think
    tumors evolve and how we treat tumors."

    Conventional cancer therapies do an effective job killing
    the majority of cells within the tumor, but they may miss
    cancer stem cells, according to the new research published
    in Proceedings of the National Academy of Sciences. As a
    result, cancers often recur.

    This is the first time that cells with stem-cell-like
    properties, have been found in solid tumors. However,
    researchers had previously found similar cells in leukemia.

    "This is a landmark study," says Irving L. Weissman of
    Stanford University in California, who discovered
    leukemia stem cells. "It is significant because all of
    the useful cancer drugs that we have, are those that
    shrink the main body of the tumor. This study reveals
    that this may not be enough."

    Both non-tumorigenic and tumorigenic cells exist within
    breast tumors.

    "Shrinking the tumor is fine, but if it doesn't get rid of
    the cancer stem cells, the cancer will grow back," according
    to Weissman.

    Stem cells are immature cells that can replicate or renew
    themselves, and are able to differentiate or mature into all
    the cells, that an organism or particular organ system need.

    Three years ago, Weissman discovered that mutations and
    rearrangements of the genomes of stem cells, that give rise
    to all the cells of the blood, can lead to some forms of
    leukemia. Weissman proposed that these changes could
    underlie the development of cancers in many tissues.

    "Ideas are cheap," says Weinberg. "Without evidence, we
    could only treat Weissman's idea as speculation. Now it
    seems that he was right on the mark."

    In the present study, the Michigan researchers examined
    cells from nine human breast tumors and tumor metastases.
    They looked for "markers"=97proteins attached to the outside
    of only some cells=97to distinguish cells.

    Using three different markers, the researchers grouped the
    tumor cells into two different classes.

    The difference between the two cell types became evident,
    when they transplanted them into mice. When as few as 200 of
    one cell type were injected into mice, tumors developed. But
    when they implanted as many as 10,000 cells of the second
    type, no tumors developed.

    "This is the classic definition of a stem cell," says
    Weissman. "Take a small subset of cells and put it in the
    organism, and see if it regenerates the original tissue.
    This is just what happens when they implant the tumor stem
    cells. All the cells of the original tumor are generated."

    The key to developing new cancer therapies, may be to focus
    on these cancer stem cells. But this is likely to be
    difficult.

    "Stem cells are more difficult to kill," says Wicha.
    "Because they are so important throughout a person's
    lifetime, they have developed mechanisms that protect
    themselves."

    For example, tumor stem cells are able to resist toxic
    substances, such as cancer drugs. More mature cells are
    easier to kill than stem cells, because these mechanisms are
    not always active.

    Normal Stem Cells vs. Cancer Stem Cells

    The stem cells in tumors discovered by researchers at the
    University of Michigan, are not the same type of stem cells
    being explored as potential therapies, to treat degenerative
    diseases. Both normal embryonic and adult stem cells are
    being actively studied for their ability, to proliferate and
    replace damaged cells in diseases such as diabetes,
    Parkinson's disease, and heart disease.

    But stem cells in tumors develop, because of mutations that
    accumulate over years and often decades. The mutations are
    thought to promote the tumor stem cells' ability to
    proliferate, eventually leading to cancer.

    The next step is to figure out what makes the cancer stem
    cells different from the other cells in the tumor. The
    researchers are currently using DNA microarrays (or "gene
    chips"😉 to identify genes that are active in the cancer-
    causing cells, compared to benign tumor cells.

    Some of these genes might control the cell's ability to
    replicate and metastasize. Identifying these genes may
    suggest new drug targets, that could selectively kill the
    cancer cells.

    "The only cells within an organism, that live long enough
    to accumulate the mutations that lead to cancer, are the
    stem cells," says Wicha. "When the cancer cell
    differentiates, it produces other cells that have lost the
    ability to self-renew."

    If the researchers can find normal adult breast stem cells,
    they may understand how breast cancers develop. "A key
    question is what is the difference between a normal stem
    cell and a tumor stem cell," says Wicha. "A normal breast
    stem cell can make copies of itself, but then shuts itself
    off. Cancer stem cells make too many copies of themselves."

    Wicha thinks that a primary event in cancer development,
    occurs when the normal stem cell loses the ability to
    regulate its own growth. But many other mutations must
    occur, to turn a normal stem cell into cancer stem cell.

    Weissman suspects that most cancers develop from mutations
    in the genomes of stem cells, in various tissues
    throughout the body.

    "I suspect that a lot of researchers studying different
    types of cancers, are going to be looking for stem cells in
    their tumors now," says Weissman.

    ----------------------

    Susan, Su_Texas my opinions

  5. Starts to sound like parasites, doesn't it?

    "Anth" <[email hidden]> wrote in message news:ocydnZkLJucu5ATdRVn-
    [email hidden]...

    Quoted message said:

    (IMO stem cells are what Beard describes as the germ cells
    in trophoblast thesis of cancer) There was a recent
    article on stem cells and Beard's thesis in New Scientist
    - you might want to try chasing it up.
    www.newscientist.com Basic theory is that cancer is a
    placenta (The theory still stands up to scrutiny today -
    this doesn't mean it is right!). In pregnancy at (56 days
    *I think*?) the babies pancreas becomes active


    and

    Quoted message said:

    it starts pumping out proteolytic enzymes
    trypsin/chymotrypsin. These enzymes kill the invasive
    cells of the placenta and stop it from growing/invading
    the mother. Anth

    <[email hidden]> wrote in message news:12914-40990CD5-119@storefull-
    3195.bay.webtv.net...

    Quoted message said:

    google.comsearch

    From what I just read, the currect cancer treatments
    might be the wrong approach, because they don't target
    cancer stem-cells.

    I was reading about cDNA, gene-chips, & cancer.

    Susan, Su_Texas my opinions

  6. <[email hidden]> wrote in message news:29591-40995066-493@storefull-
    3197.bay.webtv.net... U-M scientists find "stem cells" in
    human breast cancer

    Quoted message said:

    Discovery could explain current treatment failures, and
    lead to more effective therapies for many cancers:
    added 02/24/03

    Let's wait and see. Despite the usual journalistic hype, and
    researchers making their findings sound as significant as
    possible, I am not sure that this research is telling us
    anything that we didn't already know, or could predict.

    The cells in any cancer, unlike normal tissue cells, tend to
    vary dramatically from each other, in size and shape and
    even to having different numbers of chromosomes and numbers
    of cell nuclei. So even morphologically (on microscopic
    appearances) it is clear that there are many different
    populations of cell in a cancer. It is inevitable that such
    differences will extend to different cell behaviours, such
    as rate of cell division and ability to produce tumours if
    injected into test animals.

    Also one of the authors quoted by su_texas claims that
    mature cells are easier to kill than rapidly multpiplying
    cells, which is just not true. Many forms of chemotherapy
    can only kill cells when they are dividing, and the side
    effects on bone marrow and gut (diarrhoea etc) occur
    purely and simply because the cells there are rapidly
    dividing. Radiotherapy is also more effective on rapidly
    dividing cells.

    So it is not clear how most of the cells in a cancer being
    derived from a single rapidly dividing source would explain
    the limitations of chemotherapy or radiotherapy. It is more
    likely that there are many different cell lines sustaining
    the growth of cancer and that the *slower* dividing ones
    will be the ones resistant to treatment and cause cancer
    recurrence if it occurs..

    What do you think, Orac?

    Peter Moran

  7. Parasites not sure- could you explain? Anth

    "Gymmy Bob" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Starts to sound like parasites, doesn't it?

    "Anth" <[email hidden]> wrote in message news:ocydnZkLJucu5ATdRVn-
    [email hidden]...

    Quoted message said:

    (IMO stem cells are what Beard describes as the germ
    cells in


    trophoblast

    Quoted message said:
    Quoted message said:

    thesis of cancer) There was a recent article on stem
    cells and Beard's thesis in New Scientist - you might
    want to try chasing it up. www.newscientist.com Basic
    theory is that cancer is a placenta (The theory still
    stands up to scrutiny today - this doesn't mean it is
    right!). In pregnancy at (56 days *I think*?) the babies
    pancreas becomes active


    and

    Quoted message said:

    it starts pumping out proteolytic enzymes
    trypsin/chymotrypsin. These enzymes kill the invasive
    cells of the placenta and stop it from growing/invading
    the mother. Anth

    <[email hidden]> wrote in message news:12914-40990CD5-119@storefull-
    3195.bay.webtv.net...

    Quoted message said:

    google.comsearch

    From what I just read, the currect cancer treatments
    might be the


    wrong

    Quoted message said:
    Quoted message said:
    Quoted message said:

    approach, because they don't target cancer stem-cells.

    I was reading about cDNA, gene-chips, & cancer.

    Susan, Su_Texas my opinions



  8. (This is what I think) Basically what you have here is
    'progressive refinement.' You have a large population that
    has the potential to mutate and also have offspring. When
    you give the cancers chemo you kill the weakest ones and the
    cells left over (the stronger ones) can rebuild the
    population, thus the population is now stronger than before,
    and the process repeats.

    There's a considerable amount of damage to the DNA (because
    of the acidic environment) so you have a lot of mutation,
    the cells that fail to survive (because the DNA is messed up
    sufficiently) destruct, but the ones with the necessary
    mutations to survive, grow on to rebuild the next
    population. So what you have is a growing resistance to the
    agent used to kill them, and also growing resistance to the
    persons immune system. Do you think that the DNA damage
    could selectively switch on elements that make the cancer
    cells invasive, grow their own blood supplies ? Anth

    "Peter Moran" <[email hidden]> wrote in message news:40999184$0$10291$61c65585@uq-127creek-reader-
    01.brisbane.pipenetworks.com.au...

    Quoted message said:


    <[email hidden]> wrote in message news:29591-40995066-493@storefull-
    3197.bay.webtv.net... U-M scientists find "stem cells" in
    human breast cancer

    Quoted message said:

    Discovery could explain current treatment failures, and
    lead to more effective therapies for many cancers: added
    02/24/03

    Let's wait and see. Despite the usual journalistic hype,
    and researchers making their findings sound as significant
    as possible, I am not sure


    that

    Quoted message said:

    this research is telling us anything that we didn't
    already know, or could predict.

    The cells in any cancer, unlike normal tissue cells, tend
    to vary dramatically from each other, in size and shape
    and even to having


    different

    Quoted message said:

    numbers of chromosomes and numbers of cell nuclei. So
    even morphologically (on microscopic appearances) it is
    clear that there are many different populations of cell
    in a cancer. It is inevitable that such differences will
    extend to different cell behaviours, such as rate of
    cell division and ability to produce tumours if injected
    into test


    animals.

    Quoted message said:


    Also one of the authors quoted by su_texas claims that
    mature cells are easier to kill than rapidly multpiplying
    cells, which is just not true. Many forms of chemotherapy
    can only kill cells when they are dividing, and the side
    effects on bone marrow and gut (diarrhoea etc) occur
    purely and simply because the cells there are rapidly
    dividing. Radiotherapy is


    also

    Quoted message said:

    more effective on rapidly dividing cells.

    So it is not clear how most of the cells in a cancer being
    derived from a single rapidly dividing source would
    explain the limitations of


    chemotherapy

    Quoted message said:

    or radiotherapy. It is more likely that there are many
    different cell lines sustaining the growth of cancer and
    that the *slower* dividing ones will be the ones resistant
    to treatment and cause cancer recurrence if it occurs..

    What do you think, Orac?

    Peter Moran

  9. It would be interesting to see how the DNA mutations vary
    across the tumour? Maybe Orac has some info on this? Anth

    "Anth" <[email hidden]> wrote in message
    "]news:[email hidden]... [snip]

  10. One word. "Hulda"

    "Anth" <[email hidden]> wrote in message news:OfKdnUvWeoTCCATdRVn-
    [email hidden]...

    Quoted message said:

    Parasites not sure- could you explain? Anth

    "Gymmy Bob" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    Starts to sound like parasites, doesn't it?

    "Anth" <[email hidden]> wrote in message news:ocydnZkLJucu5ATdRVn-
    [email hidden]...

    Quoted message said:

    (IMO stem cells are what Beard describes as the germ
    cells in


    trophoblast

    Quoted message said:
    Quoted message said:

    thesis of cancer) There was a recent article on stem
    cells and Beard's thesis in New Scientist - you might
    want to try chasing it up. www.newscientist.com Basic
    theory is that cancer is a placenta (The theory still
    stands up


    to

    Quoted message said:
    Quoted message said:
    Quoted message said:

    scrutiny today - this doesn't mean it is right!). In
    pregnancy at (56 days *I think*?) the babies pancreas
    becomes


    active

    Quoted message said:
    Quoted message said:

    and

    Quoted message said:

    it starts pumping out proteolytic enzymes
    trypsin/chymotrypsin. These enzymes kill the invasive
    cells of the placenta and stop it from
    growing/invading the mother. Anth

    <[email hidden]> wrote in message news:12914-40990CD5-119@storefull-
    3195.bay.webtv.net...
    > google.comsearch
    >
    > From what I just read, the currect cancer treatments
    > might be the


    wrong

    Quoted message said:
    Quoted message said:

    > approach, because they don't target cancer stem-
    > cells.
    >
    > I was reading about cDNA, gene-chips, & cancer.
    >
    > Susan, Su_Texas my opinions



  11. "Anth" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    (This is what I think) Basically what you have here is
    'progressive refinement.' You have a large population that
    has the potential to mutate and also have offspring. When
    you give the cancers chemo you kill the weakest ones and
    the cells


    left

    Quoted message said:

    over (the stronger ones) can rebuild the population, thus
    the population is now stronger than


    before,

    Quoted message said:

    and the process repeats.

    There's a considerable amount of damage to the DNA
    (because of the acidic environment) so you have a lot of
    mutation, the cells that fail to survive (because the DNA
    is messed up sufficiently) destruct, but the ones with


    the

    Quoted message said:

    necessary mutations to survive, grow on to rebuild the
    next population. So what you have is a growing resistance
    to the agent used to kill them,


    and

    Quoted message said:

    also growing resistance to the persons immune system. Do
    you think that the DNA damage could selectively switch on
    elements that make the cancer cells invasive, grow their
    own blood supplies ? Anth

    I don't think chemotherapy makes a cancer more cancerous,
    but resistance to chemotherapy must depend on some cancer
    cells being less susceptible to immune attack. The same
    must apply when immunotherapy produces a remission, but
    then fails.

    Peter Moran

    Quoted message said:


    "Peter Moran" <[email hidden]> wrote in message


    news:40999184$0$10291$61c65585@uq-127creek-reader-
    01.brisbane.pipenetworks.com.au...

    Quoted message said:
    Quoted message said:


    <[email hidden]> wrote in message news:29591-40995066-493@storefull-
    3197.bay.webtv.net... U-M scientists find "stem cells"
    in human breast cancer

    Quoted message said:

    Discovery could explain current treatment failures, and
    lead to more effective therapies for many cancers:
    added 02/24/03

    Let's wait and see. Despite the usual journalistic
    hype, and


    researchers

    Quoted message said:
    Quoted message said:

    making their findings sound as significant as possible,
    I am not sure


    that

    Quoted message said:

    this research is telling us anything that we didn't
    already know, or


    could

    Quoted message said:
    Quoted message said:

    predict.

    The cells in any cancer, unlike normal tissue cells,
    tend to vary dramatically from each other, in size and
    shape and even to having


    different

    Quoted message said:

    numbers of chromosomes and numbers of cell nuclei. So
    even morphologically (on microscopic appearances) it is
    clear that there are many different populations of cell
    in a cancer. It is inevitable that such differences will
    extend to different cell behaviours, such as rate


    of

    Quoted message said:
    Quoted message said:

    cell division and ability to produce tumours if injected
    into test


    animals.

    Quoted message said:


    Also one of the authors quoted by su_texas claims that
    mature cells are easier to kill than rapidly
    multpiplying cells, which is just not true. Many forms
    of chemotherapy can only kill cells when they are
    dividing,


    and

    Quoted message said:
    Quoted message said:

    the side effects on bone marrow and gut (diarrhoea etc)
    occur purely and simply because the cells there are
    rapidly dividing. Radiotherapy is


    also

    Quoted message said:

    more effective on rapidly dividing cells.

    So it is not clear how most of the cells in a cancer
    being derived from


    a

    Quoted message said:
    Quoted message said:

    single rapidly dividing source would explain the
    limitations of


    chemotherapy

    Quoted message said:

    or radiotherapy. It is more likely that there are many
    different cell lines sustaining the growth of cancer and
    that the *slower* dividing


    ones

    Quoted message said:
    Quoted message said:

    will be the ones resistant to treatment and cause cancer
    recurrence if


    it

    Quoted message said:
    Quoted message said:

    occurs..

    What do you think, Orac?

    Peter Moran


  12. Oh right Hulda - I very much doubt it? I've not touched
    Hulda much mainly because her protocols have not been tested
    properly. Anth

    "Gymmy Bob" <[email hidden]> wrote in message news:qf-dnTHeVslQCATdRVn-
    [email hidden]...

    Quoted message said:

    One word. "Hulda"

    "Anth" <[email hidden]> wrote in message news:OfKdnUvWeoTCCATdRVn-
    [email hidden]...

    Quoted message said:

    Parasites not sure- could you explain? Anth


    [snips]

  13. You take a tumour from a 'immune weaked mouse' and place it
    into a 'non immune weaked mouse' it will not grow, because
    the immune system attacks it and destroys it. It is said
    that cancer cells have a thick fibrin coat to prevent the
    immune system from attacking it? Then why when you
    transplant the tumour into a non immune weaked mouse does
    the tmuour get attacked, surely if the antigens are hidden
    under a fibrin coat then the immune system won't be able to
    recognise it as foreign? Anth .

  14. "Anth" <[email hidden]> wrote in message
    "]news:[email hidden]...

    Quoted message said:

    You take a tumour from a 'immune weaked mouse' and place
    it into a 'non immune weaked mouse' it will not grow,
    because the immune system attacks


    it

    Quoted message said:

    and destroys it. It is said that cancer cells have a thick
    fibrin coat to prevent the


    immune

    Quoted message said:

    system from attacking it?

    That's not true, but there are blocking antibodies coating
    cancer cells that protect them from immune attack. The
    immunology of cancer is extremely complex. A speaker I heard
    recently said that there are at least a dozen mechanisms by
    which cancers evade immune attack

    When you think about it, the wonder is that some cancers are
    susceptible to immune attack at all, since they are
    essentially our own cells, and it is just that sometimes the
    gene defects lead them to produce unusual proteins.

    Peter Moran

  15. Ongoing Treatment?

    IF cancer stem-cells are the problem, & they can't easily be
    killed off, then you'd probably need an ongoing treatment
    designed to kill off the cancer cells as they develop, ...
    that is, after you've finished all that's currently offered
    to the general public, in traditional cancer care.

    ???

    Are there ongoing treatments like that, in regular or
    alternative-medicine?

    Susan, Su_Texas my opinions

  16. From: [email hidden] (Anth)

    (IMO stem cells are what Beard describes as the germ cells
    in trophoblast thesis of cancer) There was a recent article
    on stem cells and Beard's thesis in New Scientist - you
    might want to try chasing it up. www.newscientist.com Basic
    theory is that cancer is a placenta (The theory still
    stands up to scrutiny today - this doesn't mean it is
    right!). In pregnancy at (56 days *I think*?) the babies
    pancreas becomes active and it starts pumping out
    proteolytic enzymes trypsin/chymotrypsin. These enzymes
    kill the invasive cells of the placenta and stop it from
    growing/invading the mother.

    Anth

    =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

    So far, can't find Beard, but did find this:

    5T4 & Cancer Vaccine

    ["]http://www.newscientist.com/news/news.jsp?id=3Dns99994309]

    Stem cell mobility linked to cancer's spread,
    10:23=A024=A0October=A003=A0NewScientist.com news service=A0

    A molecule present in many spreading cancers, has been
    identified as key to helping stem cells to become mobile,
    reveal UK scientists.

    A cancer vaccine based on the molecule, has already been
    successfully trialled in humans, and a "magic bullet"
    treatment is also in development.

    As cancers grow, cells often move out of the original tumour
    and spread around the body using the blood or lymphatic
    system, a process called metastasis. These widespread
    cancers are especially difficult to treat.

    Now scientists have discovered, that a surface molecule
    called 5T4 (which is present in many different types of
    tumour), is also produced by embryonic stem cells (ESCs) as
    the embryo grows and develops.

    Peter Stern and colleagues, at Cancer Research UK's Paterson
    Institute in Manchester, found the 5T4 produced by mouse
    ESCs, made the cells spread across culture plates. "We think
    we've found a common factor in the movement of embryonic
    cells during development, and of cancer cells during the
    spread of disease," he says.

    Robert Souhami, director of clinical research at Cancer
    Research UK, says: "By studying fundamental developmental
    biology, the new study has highlighted a potentially
    exciting strategy to prevent cancer from spreading - one of
    the great challenges faced by scientists."

    Avoid rejection

    The researchers originally came across 5T4, when they
    compared the surface molecules of special ESCs called
    trophoblasts, with those found on cancer cells in humans.

    Trophoblasts form the interface between the placenta and a
    fetus. The team focused on them, because this special layer
    has to avoid rejection by the mother's immune system -
    cancer cells also manage to evade the body's immune system.

    They found 5T4 was common to both. The molecule was
    overexpressed in cancer cells, whereas non-cancerous adult
    cells did not express the molecule at all.

    The new study of mouse ESCs demonstrated, that 5T4 is the
    key to making developing stem cells mobile. In normal
    development, 5T4 is involved in helping cells move around in
    a regulated way, Stern explains. "In cancer it's not
    regulated - it's out of control."

    Immune response

    The team has already harnessed 5T4 in human clinical trials.
    Because it is expressed in the embryo only, 5T4 should be
    treated as a foreign invader by the adult body.

    The team, in collaboration with Oxford BioMedica, has
    developed a therapeutic vaccine, based on eliciting an
    immune response against cancer cells expressing 5T4. =A0=A0
    =A0"The cancer vaccine has been shown to be immunogenic and
    safe," Stern told New Scientist.

    The team is also collaborating with Active Biotech, to
    develop a "magic bullet" based on 5T4. They are using an
    antibody that latches on to the molecule, to seek out
    tumours and deliver a drug to kill them.

    The discovery of 5T4 could even give practical help to
    scientists trying to isolate pure, unspecialised ESCs,
    Stern adds.

    Stem cells differentiate easily, and 5T4 could be used as a
    marker to weed out cells, which have started to develop from
    their primitive state.

    Journal reference: Journal of Cell Science (vol 116, p 4533)
    =A0
    ----------------

    Susan, Su_Texas my opinions=A0

  17. Galectin-3, & the Modified Protein Treatment (Non-
    Stick Approach)

    ["]http://www.newscientist.com/news/news.jsp?id=3D99993801]

    Deadly spread of cancer halted,
    12:21=A005=A0June=A003=A0NewScientist.com news service=A0

    The spread of cancers through the body could be halted, by
    targeting a protein that helps cells latch on to each other,
    reveals a new study.

    The spreading of cancer from an initial tumour to other
    parts of the body - called metastasis - frequently means
    there is little hope a person can be saved. But scientists
    have now modified a naturally occurring human protein to
    disrupt this deadly process, in mouse models of human
    breast cancer.

    "We were able to significantly reduce the spread of the
    disease and decrease tumour growth, without any evidence of
    toxicity," says Gary Jarvis, a microbiologist at the
    University of California in San Francisco. "If we can stop
    metastasis in humans, we will have gone a long way towards
    successfully treating cancer."

    "It's when tumours spread to essential organs, such as
    the liver or lung, that they become fatal," says
    colleague Constance John, a research chemist. "There is
    nothing to date that has been approved by the Food and
    Drug Administration, for treatment of cancer that works
    on that process."

    Stick together

    The team modified a protein, that seems play an important
    role in helping cells stick to each other. This ability aids
    metastasis, by allowing cancerous cells that enter the
    bloodstream, to lodge themselves in other parts of the body.

    The team, lead by Jarvis in the US and Hakon Leffler at
    the University of Lund in Sweden, singled out a human
    protein named galectin-3. This is from a family of
    proteins called lectins, that bind to sugar molecules on
    the surfaces of cells.

    Galectin-3 is known to play a role in cancer formation,
    particularly in promoting cell-to-cell adhesion. "The idea
    was to break that contact and inhibit secondary cancer
    formation," says Jarvis. So the team removed the key part of
    galectin-3 that normally allows cells to stick to each
    other. The modified protein also occupies the site on a
    cell's surface, blocking normal galectin-3 from binding.
    This stops cells from adhering to each other.

    The modified protein more than halved the number of mice,
    that developed metastatic tumours. Cancer implanted into the
    mice spread to the lymph nodes or other organs, in 11 of the
    20 control mice given sham injections, but only four of the
    20 mice given the truncated protein.

    Slow growth

    The growth of the implanted tumours was also significantly
    less, in mice treated with the modified protein, compared to
    the control mice.

    "It's not only affecting metastasis," Leffler told New
    Scientist. "It's reducing the primary tumour a lot."
    Importantly, he adds, the novel treatment did not cause any
    adverse reactions.

    A drug therapy targeting galectin-3, might one day be
    effectively used in combination with currently available
    cancer medications like chemotherapy and radiation, say the
    researchers. Although, the results are "optimistic", Leffler
    cautions that "an animal model is not human".

    "We're not trying to develop a cure for cancer," says John.
    "What we're trying to do is make cancer a disease that one
    can live with."

    Journal reference: Clinical Cancer Research (June issue) =A0
    ----------------------

    Susan, Su_Texas my opinions=A0

  18. Quoted message said:

    Subject: Re: Treatments: Should Cancer Stem-Cells BeTheFocus?
    From: [email hidden]
    Date: 5/5/04 11:15 PM Eastern Daylight Time
    Message-id: <[email hidden]>

    Quoted message said:

    The spread of cancers through the body could be halted, by
    targeting a protein that helps cells latch on to each
    other, reveals a new study.

    Myth. A theory in search of some data to support it.>

    Quoted message said:

    The spreading of cancer from an initial tumour to other
    parts of the body - called metastasis

    Never can happen in the real world.

    Quoted message said:

    Cancer implanted into the mice spread to the lymph nodes

    Now that is possible.

    It is not possible for the implanted cells nor the natural
    cells of the tissues to enter the blood stream any more
    than it is possible for the blood cells to migrate into
    the tissues.

    The lymphatic system is a first line of defense against
    disease, including cancer. The cells of the lymphatic system
    line up like the cells on a fish skin. They can open up and
    allow in objects as large as other cells that need to be be
    removed from the body. It is this capacity of the lymph
    system which would have allowed the cells to "migrate". That
    is, migrate to a node where it would be trapped and
    destroyed by lysosomes.

    Damn. Why is it that these jerks cannot understand the
    obvious truths that they are studying?

    DrC PhD

  19. <[email hidden]> wrote in message
    "]news:[email hidden]...

    [snip]

    ===================

    So far, can't find Beard, but did find this:

    navi.netunitari1.htm This is what the
    Gonzalez/Dr Kelley therapy is based on. (High doses of
    digestive proteolytic enzymes.)

    5T4 & Cancer Vaccine

    ["]http://www.newscientist.com/news/news.jsp?id=ns99994309]

    Stem cell mobility linked to cancer's spread,
    10:23 24 October 03 NewScientist.com news service

    A molecule present in many spreading cancers, has been
    identified as key to helping stem cells to become mobile,
    reveal UK scientists.

    A cancer vaccine based on the molecule, has already been
    successfully trialled in humans, and a "magic bullet"
    treatment is also in development.

    As cancers grow, cells often move out of the original tumour
    and spread around the body using the blood or lymphatic
    system, a process called metastasis. These widespread
    cancers are especially difficult to treat.

    Now scientists have discovered, that a surface molecule
    called 5T4 (which is present in many different types of
    tumour), is also produced by embryonic stem cells (ESCs) as
    the embryo grows and develops.

    Peter Stern and colleagues, at Cancer Research UK's Paterson
    Institute in Manchester, found the 5T4 produced by mouse
    ESCs, made the cells spread across culture plates. "We think
    we've found a common factor in the movement of embryonic
    cells during development, and of cancer cells during the
    spread of disease," he says.

    Robert Souhami, director of clinical research at Cancer
    Research UK, says: "By studying fundamental developmental
    biology, the new study has highlighted a potentially
    exciting strategy to prevent cancer from spreading - one of
    the great challenges faced by scientists."

    Avoid rejection

    The researchers originally came across 5T4, when they
    compared the surface molecules of special ESCs called
    trophoblasts, with those found on cancer cells in humans.

    Trophoblasts form the interface between the placenta and a
    fetus. The team focused on them, because this special layer
    has to avoid rejection by the mother's immune system -
    cancer cells also manage to evade the body's immune system.

    They found 5T4 was common to both. The molecule was
    overexpressed in cancer cells, whereas non-cancerous adult
    cells did not express the molecule at all.

    The new study of mouse ESCs demonstrated, that 5T4 is the
    key to making developing stem cells mobile. In normal
    development, 5T4 is involved in helping cells move around in
    a regulated way, Stern explains. "In cancer it's not
    regulated - it's out of control."

    Immune response

    The team has already harnessed 5T4 in human clinical trials.
    Because it is expressed in the embryo only, 5T4 should be
    treated as a foreign invader by the adult body.

    The team, in collaboration with Oxford BioMedica, has
    developed a therapeutic vaccine, based on eliciting an
    immune response against cancer cells expressing 5T4.

    "The cancer vaccine has been shown to be immunogenic and
    safe," Stern told New Scientist.

    The team is also collaborating with Active Biotech, to
    develop a "magic bullet" based on 5T4. They are using an
    antibody that latches on to the molecule, to seek out
    tumours and deliver a drug to kill them.

    The discovery of 5T4 could even give practical help to
    scientists trying to isolate pure, unspecialised ESCs,
    Stern adds.

    Stem cells differentiate easily, and 5T4 could be used as a
    marker to weed out cells, which have started to develop from
    their primitive state.

    Journal reference: Journal of Cell Science (vol 116, p 4533)

    ----------------

    Susan, Su_Texas my opinions

    Thanks for the info Anth

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