Why do people and animals get cancer
more than they used to? — Michael, CA
Dear Michael,
A hundred years ago, human beings only lived to be about 50 years old. Now people are living longer, so there’s more time for cancer to develop in their bodies. That’s what I learned from my friend David Liu who researches cancer at Washington State University (WSU).
In the lab where Liu works, tiny bugs that don’t live very long at all are helping his team understand more about cancer in humans.
“The fruit fly has made a wonderful contribution to genetics and cancer research,” Liu said.
I’d heard a bit about cancer, but I was curious about genetics, too. Liu explained that humans and fruit flies have something in common. It’s not just that they enjoy a good serving of fruit. Both you and a fruit fly are made up of trillions of cells.
Inside each cell is information that determines the color of your hair, eyes, or other traits. It’s your DNA and it what makes you, well, you. You could find DNA in your blood, hair or even in your boogers.
Information stored in DNA is passed down from parents to their babies, just like it is passed down from cats to kittens, or from fruit flies to their offspring. Liu uses fruit fly cells to learn how cells grow, die, and sometimes misbehave.
When I met up with my friend Janean Fidel, she told me more about cells. She’s a veterinarian at the WSU Veterinary Teaching Hospital and takes care of my animal friends who are sick.
“Our wonderful bodies are made of cells,” Fidel said, “but those cells aren’t always perfect.”
DNA makes lots of copies of itself. Sometimes, the DNA inside cells will make a mistake. It’s a typo in the long line of instructions that tells the cells how to grow normally. Cancer-causing substances from smoking, sunlight or other hazards in the environment sometimes lead to these mistakes, which can cause normal cells to become cancerous.
At the animal hospital where Fidel works, veterinarians are trying out an interesting technique to help detect cancer cells. A useful part of death-stalker scorpion venom can latch onto cancer cells and light them up.
Three dogs — Whiskey, Hot Rod, and Browning — recently made a visit to WSU for cancer treatment. Browning had a cancerous tumor in her leg.
Instead of amputating the leg to prevent the cancer from spreading, veterinarians used the scorpion venom paint during surgery to light up the cancer cells. The glow let the surgeons know exactly where the cancer was and they removed the whole tumor. It helped save her life.
Understanding how the tumor paint works in dogs is also helping us understand how it could be used to detect cancer in humans. Learning about cancer in people has also improved the ways we understand cancer in pets. People and pets can be great partners in research.
Sincerely,
Dr. Universe
Originally pubished by Ask Dr. Universe
