When Cells Reach Out and Touch

MicroRNAs play an important role as gene regulators involved in both everyday functioning and the functioning of diseases such as cancer. Scientists at John Hopkins have discovered that the manufacture of microRNAs is promoted by cell-to-cell contact. “No one anticipated, including us, that the production of microRNAs is linked to how densely cells are packed together.” Josh Mendell, assistant professor in the McKusick-Nathans Institute of Genetic Medicine, John Hopkins University School of Medicine.
While they were studying examples of contact inhibition; the process by which cells stop multiplying when they tough each other, it was suspected that microRNA might play a role in this process. This was due to the discovery of more microRNA in animals whose cells are more tightly packed than isolated cells.
In order to test this theory, the scientists grew cancer and non-cancer cells to increasing densities and found that the higher the density of cells, the more microRNA was produced in each cell. They then performed multiple tests to determine whether this correlation was restricted to mammal cells. They found that in all of the tested cell types, the correlation between cell density and the abundance of microRNA followed a similar pattern.
This discovery is important, as reduction in the amount of microRNAs has been linked to the development of cancers. Now that the production of microRNAs may be able to be regulated by altering the densities of cells, it might be possible in the future to stop the production of microRNA by regulating the cell-to-cell contact of cancer cells. It might also be important for therapeutic use, where the production of microRNAs could be promoted by increasing cell density.

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"When cells reach out and touch." Biology News Net - Latest Biology Articles, News & Current Events. 1 May 2009. 5 Apr. 2009
Julia Imarisio - s42002394