Recent studies conducted at the University Of Maryland School Of Medicine indicate that bacterial DNA can be transferred to human tumor cells easier than into healthy human cells. Such genetic transfer, in which DNA from one organism is implemented into another organism of a different species, without traditional reproduction processes, is called lateral gene transfer or horizontal gene transfer.
In order to research the role of lateral gene transfer in tumors, researchers at the University of Maryland Marlene and Stewart Greenebaum Cancer Center are using a specific strategy involving large quantities of samples, both cancerous and non-cancerous. This strategy was invoked by The Cancer Genome Atlas (TCGA). Scientists at the University of Maryland found that 63.5 percent of the TCGA samples that they studied were from tumors. Interestingly, 99.9 percent of the tumor samples contained evidence of bacterial gene transfer.
The ability to transfer DNA from bacteria to humans is of great relevance due to the possibility of curing diseases including cancer. Bacteria can be genetically engineered with relative ease, so the ability to integrate various genes into humans brings up an intriguing point and certainly an area of scientific pursuit. Because tumor cells seem to be more susceptible to lateral gene transfer, this presents an opportunity to alter tumor cells rather than healthy cells, which is promising in terms of potential treatments.
For now, scientists are hypothesizing possible explanations for tumor cells having a better ability to take in bacterial DNA. One explanation is that the mutations in tumor cells that seem to be caused by bacteria are a part of carcinogenesis, or the process of healthy human cells becoming cancerous. Another possibility is that bacteria have some unknown advantage when they induce mutations in human cells. Regardless, lateral gene transfer from bacteria to human tumor cells is certainly an area of future research.