"We thought Zoe might get leukemia when she was 2 or 4, " her sister, Maxine, 15, says.

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For example, a high percentage of cats begin to develop symptoms of autoimmune disease such as hyperthyroid disease, inflammatory bowel disease, lupus, rheumatoid arthritis or cancer or feline leukemia and die when they are about 11 to13 years old or even before.

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He found that when he transplanted a million human leukemia cells, full-scale tumors would almost always take hold in the mice.

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When his condition worsened due to leukemia, Robert Louis-Dreyfus created Akira Holding Foundation in 2008 to hold on to his personal stake in the company.

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One of the few medical doctors to lead a big drug company, Vasella saw potential in a new leukemia drug called Gleevec when others were skeptical.

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The idea suffered major setbacks in 1999 when a U.S. teenager died in a gene-therapy trial and again soon after when several children in Europe developed leukemia after receiving gene therapy.

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When it came out with Gleevec for leukemia, Novartis thought it was only going to be a modest seller.

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Hassan met Saunders, then a PriceWaterhouseCoopers consultant, at a Leukemia and Lymphoma Society dinner when the younger man was doing work for Schering.

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His plan, though, hit a tragic snag on September 11, when Te'o lost both his grandmother and his girlfriend, the latter to a long battle with leukemia.

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The field then suffered a major setback when an Arizona teenager died in a gene therapy experiment in 1999 and two French boys with SCID developed leukemia in 2002.

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