Multitasking skills are helpful to any mother of three small children; but when her other job is building cancer-targeting nanoparticles, such skills are absolutely essential.

Beth Singer, Ph.D., a postdoctoral scholar in the laboratory of Steven Smith, Ph.D., professor in the Division of Surgery, recently demonstrated both her mothering and scientific mettle by discussing her complex work building hybrid macromolecules while she nursed her newborn son Christopher and watched over her 2-year-old daughter Nicole in the family kitchen.

Singer came to City of Hope after receiving her doctorate in biochemistry in 2002 from UCLA. In graduate school she found time to marry her husband David — whom she met at the UCLA science fiction club — and have their first child, Alexander, now 4.

Prior to that she received a Bachelor of Science degree in biochemistry from Purdue University and then worked three years at the biotechnology company Amgen, where she was instrumental in solving the three-dimensional structure of certain human therapeutics.

Singer’s engineer father and mother, a teacher, influenced her scientific bent. “My dad designed and built a house heated by solar technology when I was 12, and both my parents had an active interest in science and science fiction,” she said.

One wonders if early exposure to construction of an unusual structure led Singer, whose hobbies include reading and occasionally writing science fiction, to her current interest in nanotechnology, whose goal is to construct tiny devices (called nanoparticles) on the scale of a billionth of a meter for use in research and medicine.

In a 2006 study published in Nano Letters, Singer and Smith built and tested one such device targeting cancer cells.

Smith is a leader in the study of DNA methylation and DNA methyltransferases, enzymes that modify DNA. “His work on human and bacterial DNA methyltransferases showed that you could develop a nanotechnology if you modified DNA so that the methyltransferase binds to DNA but won’t come off,” Singer explained. “Using this approach you can use DNA as a scaffold — and put multiple methyltransferases on that scaffold.” Such scaffolds could be decorated with diverse reagents to bind to a cell’s surface and tweak its behavior.

In 2005, Singer won one of the first National Research Service Award postdoctoral fellowships from the National Cancer Institute awarded at City of Hope. The fellowship allowed her to build a nanoparticle in which a methyltransferase is fused to the protein thioredoxin, which binds to some cancer cells.

Singer then bathed prostate cancer and normal cells with a solution containing the nanoparticle, which had been labeled with a fluorescent tag for detection, to determine if the particle would bind preferentially to the cancer cells. When she examined cells microscopically, the cancer cells glowed bright green while normal cells did not, indicating that Singer had successfully targeted the nanoparticle to cancer cells.

Ultimately scientists hope the technology can be used to deliver therapy directly to cancer cells.
This work has led to international recognition. Singer was awarded a Young Investigator Travel Fellowship for the 57th Annual Symposium on Fundamental Cancer Research and invited to speak at the International Conference on Nanobiotechnology and Nanomedicine. She has also presented her work at an American Urological Association annual meeting and at a Gordon Research Conference on New Frontiers in Cancer Detection and Diagnosis.

Singer now has two research goals. “We are working with the departments of Urology and Pathology to try to distinguish between aggressive and non-aggressive prostate cancers,” she said. “As a long-term goal we would like to show that we can deliver something into the cells. The ultimate goal would be to deliver a toxin, something that would kill a cell.”