In a video posted to Jeopardy‘s official YouTube account on March 6, Alex Trebek announced he has been diagnosed with Stage-IV pancreatic cancer. In an optimistic, but solemn statement, Trebek vowed to fight the disease and win. Recent advancements in cancer research may help his prognosis.
“Just like 50,000 other people in the United States each year, this week I was diagnosed with Stage-IV pancreatic cancer,” Trebek, 78, said in the video. “With the love and support of my family and friends, and with the help of your prayers also, I plan to beat the low survival rate statistics for this disease.” As the host of the popular “answer-and-question” quiz show Jeopardy! for 35 years, Trebek, a Canadian-American, is one of the nation’s most familiar and friendly faces. However, he won’t just have his fans’ prayers and best wishes on his side. Let’s look at the kinds of gene therapy currently at the cutting-edge of modern medicine.
Gene therapy is a cutting-edge treatment that affects specific genes inside the human body. There are three known types of gene therapy—mutation compensation, or overcoming cell mutation by adding good genes to cells; RNA interference, which prevents genes from communicating during the synthesis of gene products; and tumor-specific viruses.
To achieve mutation compensation, doctors can actually introduce a virus to the body that they’ve disabled and prevented from reproducing. They do this because the virus is secretly carrying healthy genes like P53. “P53 is a tumor-suppressor,” said Dr. David Sadava, Adjunct Professor of Cancer Cell Biology at the City of Hope Medical Center. “It’s involved in stabilizing the genome; so, if it mutates, we’re in big trouble—it’s a tumor.” Then the P53, smuggled in by the disabled virus, gets to work on the tumor in the patient. It’s not unlike the fabled Trojan Horse, if the soldiers of Troy were cancerous cells. When its work is done, the cell mutation has been seriously debilitated.
The second type of gene therapy is RNA interference, which inhibits the expression of oncogenes. An oncogene, according to the National Cancer Institute, is “a gene that is a mutated form of a gene involved in normal cell growth. Oncogenes may cause the growth of cancer cells.”
RNA interference does exactly what it sounds like. “Messenger RNA is the copy of the blueprint to give a protein,” Dr. Sadava said. “The body makes the messenger RNA but it says, ‘I don’t want to use it; the RNA is in the cell.’ [The body] makes a small RNA and the RNA binds to, by base pairing, this target—the messenger RNA—and essentially the messenger RNA doesn’t work.” Dr. Sadava explains that RNA research could manipulate our genes into turning off oncogenes. “It’s interfering with RNA,” Dr. Sadava said. “You block RNA expression, and essentially the RNA gets destroyed.”
Finally, tumor-specific viruses. Cancer researchers have developed viruses that are called oncolytic viruses. Oncolytic viruses latch onto a tumor cell, reproduce within the cell, then destroy the cell. “When it infects a normal cell, it doesn’t replicate, and the cell is undamaged,” Dr. Sadava said. “This is really the leading-edge of cancer therapy.”
To put it simply? “It infects a tumor cell, the virus replicates, more virus, tumor dead,” Dr. Sadava said.
Gene therapy is still in its early stages, but human clinical trials are beginning to surface. Of course, Jeopardy! host Alex Trebek and his medical team will decide what treatment plan to pursue. Trebek, however, could very well be one of the first patients to successfully undergo gene therapy for pancreatic cancer, while first using traditional methods like radiation therapy to slow down the cancer progression.
Dr. David Sadava, Ph.D., contributed to this article.
Dr. Sadava is Adjunct Professor of Cancer Cell Biology at the City of Hope Medical Center in Duarte, CA, and the Pritzker Family Foundation Professor of Biology, Emeritus, at The Claremont Colleges.