Cancer research will accelerate meaningfully towards the goal of control of all cancer only when a majority of researchers are working on mechanisms common to large number of different cancer types. There are too many subtypes of cancer and too few scientists to make real progress when tackling cancers one by one. Shutting down metastasis is one grail of cancer research, as the majority of cancer deaths are caused when cancer spreads throughout the body, not by the initial tumor. Thus a search for common mechanisms of metastasis is one of the few presently viable approaches to the production of broader cancer therapies. Researchers here find eleven genes that are critical to low-level processes in metastasis, broadly common across cancers. This provides a new set of targets that may lead to future ways to suppress the spread of cancer, making the condition much less dangerous.
"Metastasis kills 90 per cent of all patients who have cancer, and with this study we have discovered new ways to potentially end metastasis." In the study, the team used a unique platform it created - a shell-less avian embryo - to visualize the growth and spread of cancer cells in real time. The researchers used a molecular tool called a knockout library to insert short hairpin RNA (shRNA) vectors into cancer cells that bound to specific genes in the cells and stopped them from activating. They then inserted those cancer cells into the shell-less embryos and observed as they formed clusters of cancer, identifying which ones showed properties of being non-metastatic.
"When we found compact colonies of cancer, that meant that the key steps of metastasis were blocked. After that we could pull them out, query what the gene is and then validate that the gene is actually responsible for metastasis." The approach allowed the team to detect and identify 11 genes that play essential roles in cancer cell metastasis. According to the researchers, the genes discovered are widely involved in the process of metastasis and not unique to any one cancer. They now plan to test the metastasis-associated genes and gene-products as drug targets with an aim of stopping metastasis.
"We know that cancer, once it becomes metastatic, will keep spreading to other parts of the body and continue to get worse because of that. If we can stop metastasis at any step of progression in cancer patients, we're going to have a significant effect on survival." The team is now hoping to progress its research to human trials over the next few years. The team is also expanding efforts to explore for other types of genes called microRNAs that may present even stronger therapeutic targets for preventing metastasis.