Perhaps DNA vaccines would work better if the same approach taken with some attempts at gene therapy—to clone the bacterial DNA into a viral vector that would integrate more efficiently into the human...

Perhaps DNA vaccines would work better if the same approach taken with some attempts at gene therapy—to clone the bacterial DNA into a viral vector that would integrate more efficiently into the human chromosome than naked DNA—was used. In the case of gene therapy using viral vectors, cancer has been a potential problem in some cases. How could this happen?