Cell Polarity: Fishing for New Ways to Block Cancer
It seems ridiculous to say that understanding a fish could hold the key to life or death, but this may be the case with the tiny zebrafish, whose embryos develop similarly to those of humans. Why this little coincidence may one day save lives has to do with the way humans grow into the people they are. During embryonic development, cells develop into different tissues and organs through tiny changes in cell form, movement and function—a process known as cell polarity. However, certain molecules and genes can cause cell polarity to malfunction, leading embryos to develop abnormally. The same molecules and genes involved in cell polarity also lead to over 80 per cent of human cancers. What causes these glitches in the first place? That’s what Dr. Brian Ciruna hopes to discover as Canada Research Chair in Developmental Genetics and Cell Biology. And he’ll get answers by studying zebrafish embryos, which are not only remarkably similar to humans’, but are also abundant, transparent and easily grown under the microscope. Ciruna has pioneered two techniques to use in his research. First, he captures images of zebrafish cell movement. Second, he can turn the molecules and genes that may control cell polarity on or off. By manipulating zebrafish embryos and watching the results, Ciruna is gradually building an understanding of what underlies the process of cell polarity, an understanding he can then apply to the spread of cancerous cells. More than the tumour, it is this spread of cancerous cells, called metastasis, that usually causes death. This understanding will give new hope to many cancer sufferers, and to the millions of Canadians who will be diagnosed during their lifetime. Understanding the spread of cancer—not just its cause—is vital, since tumours and the cells that cause them often remain, even after successful treatments. Just like the disease itself, individual cancer cells and tumours may never be wiped out, but, with the help of Ciruna’s work, we may be able to stop their spread, dramatically improving the chances of survival for millions of people.