Final answer:
Studies have shown that dogs, with their highly advanced sense of smell due to a large number of olfactory receptors, can detect cancerous cells through odorant molecules. Dogs outperform humans in this regard due to their more developed olfactory system, making them excellent candidates for cancer detection research.
Step-by-step explanation:
Scientific research has shown that dogs possess an extraordinary olfactory ability, attributed to their increased number of functional genes for olfactory receptors, which ranges between 800 to 1200, in contrast to fewer than 400 in humans and other primates. This robust olfactory genetic endowment enables dogs to detect subtle odorant molecules, including the volatile chemicals indicative of certain diseases, such as cancer. Notably, some studies have explored utilizing trained dogs to identify lung cancer by analyzing urine samples. The hypothesis behind these studies is that cancerous cells may release specific odorant molecules that dogs can detect, making them more efficient detectors compared to humans. This aptitude of dogs, with their heightened sense of smell, could better harness the scent of cancer for early detection, potentially saving lives with quicker diagnoses.
Breeding programs have taken advantage of the dogs' olfactory capabilities; for instance, Bloodhounds were specifically bred to enhance their sense of smell, resulting in a greater number of olfactory receptors and larger olfactory epithelia. Understanding such mechanisms allows scientists to explore the potential of applying this biological 'trick' to human cells in a controlled way, with the aim to further advance cancer detection methods and treatments.