Placeholder Image

字幕表 動画を再生する

  • More than 100 years ago, a British doctor, John Beard, noted that cancer cells behaved

  • much like human trophoblasts (embryonic cells), which are referred to today as stem cells.

  • In 1911, he published a book called, “The Enzyme Treatment of Cancer and Its Scientific

  • Basis,” in which he expounded on his theory that cancer was caused by these primitive

  • precursor cells, and that enzymes could be used to treat the disease.

  • Dr. Beard noticed that the placenta (which forms from part of the fertilized egg) had

  • many similarities to a tumor, in that it exhibits uncontrolled and invasive growth. Some tumors,

  • like placental cells, even secrete the hormone HCG. Placental cells multiply unchecked until

  • the fetal pancreas begins secreting enzymes, at which point the placenta stops growing.

  • This led Dr. Beard to the conclusion that enzymes might also inhibit the growth of tumor

  • cells.

  • Tests on mice implanted with tumors showed that injections of pancreatic enzymes caused

  • their tumors to shrink. Dr. Beard then tested enzymes on human patients, with positive results.

  • However, Dr. Beard’s theory never caught on with the scientific establishment, and

  • he died in obscurity in 1924.

  • However, it appears that Dr. Beard was correct all along. New research shows that tumors

  • do in fact originate from stem cells, which form the basis for the recurrence of tumors,

  • and also for the development of chemotherapy resistance. Most forms of chemotherapy and

  • radiotherapy kill only the quickly-dividing progeny of cancer stem cells, temporarily

  • destroying the bulk of the tumor. However, if even one stem cell survives, it will soon

  • recreate the original tumor.

More than 100 years ago, a British doctor, John Beard, noted that cancer cells behaved

字幕と単語

ワンタップで英和辞典検索 単語をクリックすると、意味が表示されます

B2 中上級

がん幹細胞とは? (What are Cancer Stem Cells?)

  • 133 19
    Stone Young に公開 2021 年 01 月 14 日
動画の中の単語