The Immortal Life of Henrietta Lacks by Rebecca Skloot
My rating: 5 of 5 stars
Current Goodreads Rating: 4.04
HeLa cells are of one of
the most important cell lines used in research today. They have aided in
developing the polio vaccine and cancer treatment drugs like Taxol. HeLa
came from the cervical cancer cells of an African American woman named
Henrietta Lacks. She died over 60 years ago, but HeLa cells still
live. While she received her first radium treatment at Johns Hopkins,
doctors took a sample of her tumor without her or her family knowing.
After scientists discovered that Lacks' cells replicated and hadn't died, they
realized their value to research since they could be tested without harming
animals or humans. A billion dollar industry of producing, selling, and
trading the cells soon precipitated. Meanwhile, the surviving Lackes
could not even afford health insurance. They received none of the profits
from their mother's cells, sparking debate about the ethics of using patients'
bodily scraps for scientific advancement without consent. HeLa has played
a monumental role for science, but they wreaked havoc on the Lacks'
family. Years later, the family has never sued Johns Hopkins or any other
doctors for stealing Lacks’ cells. Their main focus is trying to make the
world aware of the woman behind the famous cells.
Inserting its DNA into one arm of her eleventh
chromosome and turning off her p53 tumor suppressor gene, HPV caused Lacks'
cancer. There was a loss of cell cycle control, and the cancer cells divided
rapidly and invaded other tissues. These cells do not exhibit
density-dependent inhibition or anchorage dependence. She was diagnosed
with epidermoid carcinoma of the cervix. However, she was wrongly
diagnosed. Instead, her cancer's origin was glandular tissue rather than
epithelial tissue. This type of cancer metastasizes much faster than
epidermoid carcinoma. Yet, her syphilis may have also been a factor in
the cancer's spreading, for it weakens the immune system. Regardless of
the cause, the cancer metastasized to other parts of Lacks' body, explaining
why “her other organs were so covered in small white tumors it looked as if
someone had filled her with pearls” at the time of her death (Skloot
118). Ultimately, the cancer prevented other parts of her body from
functioning. Because tumors blocked her urethra, Lacks died from the
buildup of toxins that should have been released through urine.
Unlike normal somatic cells, Lacks’ cancerous cells
were immortal because of her telomeres never shortening. Normally,
telomeres at the end of chromosomes shorten with each cellular division.
After they are almost gone, the cell stops dividing and dies. Yet, HeLa
contains an enzyme called telomerase that rebuilds telomeres, meaning that the
cell is given more time before its death. The presence of telomerase is
the reason that HeLa is immortal. Whenever cultured with other cells,
HeLa always outlived them. Because of their immortality, Lacks’ cells
will always be an available resource for research and contribute to new
discoveries.
Scientists are always careful to prevent cross
contamination, but HeLa cells are able to float on dust particles or travel
from lab to lab, riding on the scientists’ shoes. If one HeLa lands in a culture dish, the HeLa
cells could take over the entire dish.
Therefore, instead of conducting useful research, scientists may have
simply regrown more HeLa. Years of
research and millions of dollars were wasted in addition to finding out that
spontaneous transformation didn't exist, but rather cells were invaded by
HeLa. So, a promising possibility for
finding a cure for cancer was then extinct, according to Dr. Gartler who came
up with the HeLa contamination hypothesis.
3. In 1951, when doctors
took a sample from Lacks without her permission, it wasn't illegal. It still isn't illegal. When tissues are a part of one's body, they
are definitely his or hers. However,
when they are no longer a part of the body, as a removed mole or red blood
cells from a blood test, they most likely get stored somewhere for future
research. Without these, testing for
possible cures to diseases wouldn't be possible, but people have trouble
accepting that their cells are used for purposes to which they are
unaware. They still feel a sense of
ownership even though the cells are from parts of their tissues that they
voluntarily gave. Further complications
arise when these cells have value like the HeLa cells. Someone other than the owner of them makes
money, and he or she gets nothing. If people
are aware that their cells are valuable, they can paten them, but most people
are never told this information.
Evidently, the issues concerning ethics in The Immortal Life of Henrietta Lacks continue to be relevant and
will probably pose more issues in the future as researching develops.
Skloot touches upon all four of the big ideas studied
in AP Biology in her book. First, HeLa
cells have evolved while growing in culture like they would in a human
body. Exposure to light, chemicals, and
different environments causes the DNA to change which can be passed on to
future generations of cells after cell division. Though once containing the same DNA as Lacks,
HeLa has evolved, leading to diverse DNA.
Yet, HeLa is still considered human.
Next, cancer cells can divide infinitely if continually supplied with
nutrients. They need an energy source
and building blocks to grow and reproduce.
In search for nutrients and oxygen, the cancer may spread or generate
its own blood supply. Additionally,
cells store and transfer DNA.
Specifically, doctors wanted blood samples from her children to compare
to HeLa's in order to create a map of Lacks' genes to solve the contamination
problem. Theoretically, one half of her
children's DNA would be from her and the other from their father. Lastly, HeLa has biological systems that
interact on a cellular level. During
mitosis, the mitotic spindle cooperates with the chromosomes; motor proteins walk
the chromosomes along the microtubules to separate poles during anaphase and
eventually form two daughter cells.
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