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DEATH and EVERLASTING LIFE Damage DNA—The Genetic Material in Cells— the Radiation Treatment Lacks Received So That the Cells Can't Divide Anymore

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DEATH and EVERLASTING LIFE Damage DNA—The Genetic Material in Cells— the Radiation Treatment Lacks Received So That the Cells Can't Divide Anymore BIOLOGY: Cancer Cells //CHEMISTRY: Radioactivity //PHYSICS: Nanotechnology enrietta Lacks, a 30-year-old Scientists had been trying to culture African-American woman, went human cells, or grow them in a lab, for a to Johns Hopkins Hospital in long time. But no matter what they did, the Baltimore, Maryland, in 1951. For cells died. Lacks's cells thrived. (Scientists months, she had felt pain in her now think it's partly because a molecule Hcervix, the lower part of the uterus. A doctor called telomerase, which protects DNA from examined her and foimd an abnormal lump damage, is unusually active in her cells.) of tissue, called a tumor, growing there. Lab Lacks's cells have fueled nearly 75,000 tests showed that the tumor was cancerous. studies in genetics, cloning, vaccines, and Cancer develops when cells divide and other areas of biology. Last year, for the first grow uncontrollably. Doctors at the hospital time, her descendants were given a say in gave Lacks the standard treatment of the day: research conducted on her cells. They sewed small packets of radium, a radio- active element, onto the tumor. Radiation can DEATH AND EVERLASTING LIFE damage DNA—the genetic material in cells— The radiation treatment Lacks received so that the cells can't divide anymore. didn't stop her cancer and she died later But the doctors did something else too: that year. Remarkably, though, her cultured They took tissue from Lacks's cervix without cancer cells survived and reproduced in test telling her, which was typical back then. tubes. They grew just as aggressively as they The tissue was placed in test tubes and kept had in her body. Every day, they doubled in warm in an incubator. Doctors hoped the number. The cells were immortal. cells would survive outside of Lacks's body Scientists who heard about them asked so they could be used for medical research. for samples, and soon Lacks's cells arrived in 1. THE» HENRIETTA LACKS 1951 Doctors take cancer cells from Henrietta Lacks, who has cervical cancer, without her knowledge or permission. They name them "HeLa" HeLa CELLS cells. Despite treatment. Lacks dies from the disease later that year. Turn the page for more of POLIO HeLa's historic VACCINE 1952 HeLa cells survive shipment by mail— the first successful transport of live cells. Scientists use them to study HeLa cells are the first to viruses and to test be successfully cloned, the polio vaccine. or copied exactly. labs around the world. They were given the infecting them with diseases or administering name "HeLa," combining letters fi-om her first high doses of drugs. Such experiments helped and last names. scientists understand how human cells work HeLa cells allowed researchers to run and led to the development of vaccines and experiments on human cells that they treatments for diseases (see time line above). couldn't ethically do on people—such as Continued on the next page WWW.SCHOLAST1C.COM/SCIENCEWORLD 15 ]n the past 63 years, several scientists smaller molecules called bases, which are have won Nobel prizes for research on HeLa represented by letters. A genome is the list of cells. Winners of national student research letters in a DNA sequence. Lacks's genome con:ipetitions have used them too. "It's hard will help scientists learn more about how to find a biology lab that doesn't have HeLa human cells work. cells sitting in the freezer or incubator," Her genome wasn't the first to be says Kathy Hudson, deputy director at the published, but in the other cases, the people National Institutes of Health (NIH), the who provided samples gave scientists permis- agency in charge of U.S. medical research. sion to use them. "They said, 'I'm OK with my sequence being publicly available,'" says A FAMILY'S LEGACY Hudson. "Henrietta wasn't asked." Last year, scientists in Europe published There was another problem. A genome the genome of HeLa cells on the Internet. can reveal personal information, such as DNA molecules are made of a string of which diseases someone might develop. And 1960 1965 HeLa cells travel HeLa cells are into space aboard combined with mouse a Russian satellite. cells to make the first Later, NASA sends hybrid cells from two more HeLa cells into different species. Such space, discovering cells were used in that they reproduce research on genetics faster in low gravity. and cell division. 1989 Researchers Scientists use working with HeLa HeLa cells to cells discover that study HIV, the virus a molecule called that causes AIDS. / telomerase protects the DNA in human WHITE chromosomes from HOUSE damage due to aging AIDS RIBBON Scientists use HeLa cells to learn how the bacteria that cause tuberculosis enter human cells. 16 MARCH 3,2014 since family members share sinülax DNA, a find a way to keep Henrietta's DNA sequence person's genome holds clues about diseases somewhat private without cutting off their relatives might be susceptible to. scientific progress. "They are really proud of Henrietta Lacks left behind five children, the contribution Henrietta Lacks's cells have ages 16, 12, 4, 2, and 1, when she died. She made to biology," says Hudson. has many living descendants today. When Together, the family and the NIH came to researchers pubUshed the HeLa genome in an agreement. Researchers can use the HeLa °^ have HeLa 2013, they hadn't informed the Lacks family genome by applying to the NIH for access. A or asked their permission, since they weren't group of scientists and Lacks family members required to. When the family expressed reviews the applications. And from now on, concerns about privacy, the scientists when scientists publish research conducted removed the sequence from the Internet. using HeLa cells, it'll include a note thanking Hudson and other NIH leaders then met Lacks and her family for their everlasting with the Lacks family. Her relatives wanted to gifts to science. •^ —Jennifer Barone 1971 Henrietta Lacks is 1973 identified by name for the first time in Lacks's children learn that an article honoring their mother's cells are George Gey, the immortal and are used scientist who cultured in research worldwide. HeLa cells, following The same year, scientists his death in 1970. take blood samples from members of the Lacks family for genetic analysis s without proper permission. 5 !ü o 1984 Research on HeLa cells proves that a virus known as human papillomavjrus, or HPV, can cause cervical cancer (which killed Lacks). A vaccine that protects against some strains of the virus became available in 2006. 2005 Researchers The HeLa cell genome test how quickly is published online HeLa cells absorb without permission nanoparticles. The from the Lacks family. results suggest The family and the NIH new methods for reach an agreement delivering drugs for future use of the to cancer cells. genome in research. WWW.SCH0LASTIC.COM/SCIENCEW0RLD 17 Copyright of Science World is the property of Scholastic Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. 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