This electron micrograph from a study at Caltech shows several siRNA-containing targeted nanoparticles both entering and within a tumor cell.

Caltech/Swaroop Mishra

If you were a moviegoer in the 1980s, there's a solid chance you caught the flick "Innerspace." In this movie, the main character is miniaturized in a scientific experiment. The objective is to inject him and his tiny shuttle into a rabbit. Not everything goes as planned; he ends up inside a person instead. An action-packed storyline about how our pilot gets out then ensues. Sound far-fetched? Well, it may not be so fantastical in the scientific world of nanotechnology, where nanobots -- tiny robots -- may one day have such promising medical purposes.

In the ideal situation, nanobots -- possibly powered by the charged particles in our blood -- sneak through your body delivering medications or fixing your ailments. They could possibly be tracked via attached cameras or ultrasonic signals. Or, a more promising tracking method is using an MRI machine to interact with their magnetic nature [source: Vaidya].

Still sound like a fantasy? As it turns out, nanobots are becoming an optimistic type of treatment for cancer. But before you can learn about nanobots and their potential cancer-fighting nature, you need to understand how cancer develops. Genetic mutations change the way our cells behave. Instead of going about their normal business, our cells start growing abnormally, negatively affecting our tissues. So how do nanobots come into play in treating cancer? Read on to the next page to find out.