The Protein That Could Stop Cancer in its Tracks

Researchers at Children’s are studying how cancer spreads—and maybe how it stops.

A dozen different languages echo around the entrance to the Cincinnati Children’s Hospital Medical Center (CCHMC) as patients and doctors, parents and nurses, relatives and technicians bustle through the sunlit atrium. Tanya V. Kalin leads the way—the long way—out of the public space to her laboratory. “I try to walk 10,000 steps a day,” she says. “Children’s encourages us to walk and it’s good. Yesterday, I did not walk that many, but the day before I did.”

Illustration by Doug Chayka

Just a few paces through a key-carded double door, the lobby chatter fades as the wide public thoroughfares narrow. Vibrant splashes of color perk up the white walls. At first glance they appear to be abstract prints. On closer inspection, they’re dramatically colored photomicrographs—highly magnified biomedical specimens.

“These images are from laboratories in this building,” Kalin says. “They are from our research.” This is the research neighborhood of CCHMC, where biomedical technicians delve into the chemistry of diseases under treatment on the hospital’s clinical floors. Back here, tucked away from the public, Kalin and her team ponder a particular life-or-death protein. Understanding this protein and the gene that creates it could unlock treatment, even prevention, for some cancers and other diseases.

Metaphors fall apart when trying to describe genes and the DNA from which they are made. While it is common to compare our genetic code to a sort of blueprint, blueprints don’t forge hammers or bake bricks while building houses. Your genes, on the other hand, generate proteins that both influence how your body is built and actually become parts of your body.

You are constructed from as many as 100,000 different proteins, each assembled from a unique combination of amino acids. Many of these proteins are created from a template encoded in your genes. Science has only begun to unravel the complicated interaction between your genes, your body, and your health. Kalin’s work, focused primarily on one gene and its associated protein, provides insights into this complex and interconnected system.

Space is at a premium in the CCHMC research wing. Past some filing cabinets and desks, Kalin’s compact office opens onto a short foyer leading to her laboratory. Inside her office, a light blue lab coat hangs on a hook. Tissue-paper sculptures marked “Happy Mother’s Day” decorate the shelves; a color print-out of a mother giraffe licking the head of her very young calf is taped to an overhead compartment. “Giraffes are my favorite animals,” Kalin says. “They have such big eyes.”

Her own dark brown eyes, framed by glasses, widen as she speaks, a touch of her native Ukraine still evident in her voice. Her desk is covered with documents, but not a sheet seems out of place. The small piles reflect paperwork in motion: purchase orders, invoices, grant applications. The research enterprise runs on paper. “We have to get the data for new grants to get funding and to publish papers,” she says.

The paperwork includes requests for funding from the National Institutes of Health, the American Cancer Society, and other agencies and foundations whose generosity supports Kalin and her staff of six, including a post-doctoral fellow, a technician, and three students working toward doctoral degrees. A second post-doc has just joined the team.

Compared to Kalin’s office, her laboratory is quite large, with tall ceilings and rows of lab benches topped by shelves stuffed with supplies and equipment. No one in this laboratory seems to sit. Everyone is moving, measuring, weighing, marking samples. The lab has the electric atmosphere of a start-up and the team works start-up hours, driven by the demands of the experiment in process on any given day.

Chinmayee Goda chats with Fenghua Bian, the new post-doc, updating her on current projects. Goda’s earbuds lie silent on her shoulder, and there’s an MP3 player in her pocket. “Sometimes I’ll have to run a lot of specimens, the same thing over and over,” Goda says. “Then I like my music. It’s mostly pop. I like Simon & Garfunkel.”

Two grad students working back-to-back under matching sterile fume hoods—vented work spaces—swiftly transfer a liquid that looks like sparkling rosé into rows of plastic test tubes. It’s actually fibrotic lung tissue on its way to analysis. They began collecting these samples at 4 a.m. and their day isn’t over yet.

Students compete for positions in Kalin’s lab. Word got around, even before she won the Children’s Hospital Mentoring Achievement Award in 2014, that Kalin was an exceptional advisor who championed her students and post-docs. “I feel really lucky to be part of this lab,” says Markaisa Black, on a break from transferring fibroblast samples. “The caliber of science is amazing and continues to advance.”

Much of her own success Kalin attributes to the scientist who mentored her, Rob Costa, a renowned cancer researcher at the University of Illinois at Chicago. Kalin arrived in Chicago as a post-doctoral fellow in 2000. She had already earned both an M.D. and a Ph.D. from academic institutions in Moscow. An interest in tumor immunology brought her to Costa’s laboratory in the Department of Molecular Genetics. It was there that Costa introduced her to the protein known as FoxM1.

“I got interested in this unique protein when I was a post-doctoral fellow with Rob Costa,” Kalin says. “He is the one who first cloned this transcription factor. He was the first one who thought that the knowledge of how this protein functions can be important for cancer.”

Transcription factors like FoxM1 are proteins that act like automobile pedals for your genes: They can put the brakes on to slow down a genetic process, or hit the gas and speed things up.

Costa discovered the FoxM1 protein and studied the Fox family of genes and how they control genetic activity. While Costa’s work focused on how these genes operate in the liver, Kalin has explored the role Fox proteins play in the prostate gland and in the lungs. Costa was not yet 50 when pancreatic cancer ended his life. It is apparent that Kalin still feels the loss. “He was a very talented scientist,” she says. “Several people from his lab decided that we had to keep his science alive. That is why we are working with FoxM1.”

Despite the name, Fox genes and Fox proteins have nothing to do with foxes. “Fox” is a contraction of “fork-head box,” which describes the shape of the proteins generated by these genes. The entire Fox family of genes is important as cells grow, multiply, and differentiate into various organs, and they may also play a role in cell longevity.

The irony of Fox gene expression—the mechanism by which a gene “turns on” and makes proteins—is that these genes and their associated proteins can be deadly, yet they are absolutely essential to human life. Mouse life, too. “Mice without FoxM1 are not born,” Kalin says. “They die. They die very early, when the embryo is very little. If they did not express FoxM1, they could not develop even in uterus. It is very important.”

Having fulfilled its essential role in the embryo, the FoxM1 gene goes mostly inactive as the mouse, or the human, is born and matures. Since it is part of our genetic make-up, the gene never goes away, but lies inactive on chromosome 12 in humans. If your body is damaged in some way—by radiation, for example, or carcinogenic chemicals, or physical injury—FoxM1 reactivates, often with dire consequences.

“FoxM1 is important for lung cancer. Depending on the levels of this protein, the cancer can be very aggressive,” Kalin says. “FoxM1 is not expressed when the lung is normal. In the adult lung it is not expressed. But when something happens the levels go up.”

FoxM1 is not the only transcription factor involved in cancer, but it plays a critical role in making cancerous tumors more dangerous. Kalin’s team has proven that disabling FoxM1 or disrupting its ability to affect other genes can keep some cancers from developing at all. FoxM1, Kalin has found, is part of an extended chain of chemical communication that begins with cell damage and results in a tumor. Breaking the chain of communication shows promise for identifying prevention, and maybe, cures.

Kalin’s path to Cincinnati and to CCHMC began in the Ukraine in the late ’80s. In the countries of the former Soviet Union, students graduate directly from high school into medical school and Kalin opted for a program that offered both a medical degree and a researcher’s Ph.D., so she could contribute to medical progress without seeing patients.

“I wanted to be a physician since I was quite young. That changed in high school,” she says. “I spent a lot of time in clinics. One day, as we were waiting, I listened to [patients] complaining that they couldn’t sleep, and over here, someone was complaining that all she did was sleep. I thought, I’m not sure I could listen to this all day. I later learned it wasn’t like that at all, and I work very closely with some remarkable clinicians now.”

Collaboration requires communication and communication requires talking in offices all over the CCHMC complex. “It leads to lots of additional steps on my Fitbit,” Kalin says.

Discussions with University of Cincinnati Health radiologists led Kalin’s team into research on a non-cancerous problem in the lungs, a condition called Idiopathic Pulmonary Fibrosis. Pulmonary Fibrosis can be a cruel side effect of radiation treatment, but it can also occur for no clear reason, manifesting itself in some patients by filling their lungs with scar tissue that inhibits breathing. There is no known cure. In medicine, “idiopathic” is another way of saying “It’s a mystery.”

“This is what I want to do,” Kalin says. “I want to deal with important medical problems that do not have answers.”

Kalin offered to explore this fibrosis, and discovered that FoxM1, the same transcription factor she studied in lung cancers, was involved. “We started to work to see if the patients who have the fibrosis, what are the levels of this transcription factor?” Kalin says. “It looks like high levels predisposed the patient for this complication because the FoxM1 keeps the cell in this activated and cycling state.”

Kalin proved that mice bred to generate much more of the FoxM1 protein than is normal developed severe fibrosis after radiation. Mice in which FoxM1 was deactivated did not.

As lead author or coauthor of more than 40 scientific papers in the past 20 years, Kalin has a reputation approaching rock-star status within the biomedical community. In 2013, in a paper published in The Journal of Biological Chemistry, she demonstrated how FoxM1 is essential in order for prostate cancer to develop in mice. Conversely, she showed that when FoxM1 was depleted, tumor activity dropped remarkably. “It is possible that FoxM1 is important for both cancer initiation and cancer progression,” Kalin says. “Our findings provide the foundation for the development of new therapeutic approaches based on inhibition of FoxM1.”

Kalin’s insights into the mechanism of cancer and pulmonary fibrosis are having an impact around the globe. She has been invited to speak at scientific gatherings in Versailles and Shanghai. She has also been invited to participate in review panels for major funding agencies like the National Institutes of Health. It’s a prestigious appointment, but sedentary.

“The worst part is, you have to sit for eight or 10 hours—per day,” Kalin says. “I don’t get my 10,000 steps those days.”

Kalin was initiated into the laboratory culture in medical school. Although her initial tasks were menial, she got caught up in the esprit de corps all around her.

“My first job was to wash the laboratory glassware and to clean the floors. Eventually they gave me simple tasks like isolating some genetic material or staining a tissue sample,” she says. “They accepted me as a real person and they trusted me. There was such enthusiasm. The whole lab stayed until after midnight, talking about our work.”

Fond memories of her first laboratory inform Kalin’s management style today. She wants to inspire that level of camaraderie in her own lab. Sometimes inspiration begins at a 9 a.m. meeting in which the entire crew maps a research schedule for the year ahead. While most chemicals can be ordered and shipped overnight, transgenic mice, genetically modified to contain DNA from another organism, have to be specially bred. That takes time and scheduling.

Throughout Kalin’s laboratory, there are all the accoutrements of scientific inquiry: flasks and bottles, racks and frames, scales and centrifuges, lots of computers, liquids of various colors. And yet, the genetic processes studied here take place at the invisibly microscopic, molecular level inside the complex architecture of living creatures. How does Kalin know, for instance, when a protein like FoxM1 is active or not?

Using a chemical called Green Fluorescent Protein helps. This dye, derived from jellyfish, glows green under ultraviolet light. Kalin’s team has found a way to attach this marker to FoxM1 proteins.

In tissues surrounding cancerous tumors, cell nuclei glow bright green when viewed under a microscope—a sign that FoxM1 is hard at work telling chromosomes to build support systems for a tumor. When FoxM1 is deactivated or deleted, the glow migrates out of the nucleus and into the cell’s cytoplasm where the gene is inactive.

It is possible that a drug could be developed to deactivate FoxM1, and Kalin has been looking at chemical candidates that might become that drug. Her team found some likely molecules in a vast “library” of chemical compounds donated to science by Procter & Gamble 10 years ago. P&G provided Cincinnati’s biomedical researchers with full access to more than 250,000 chemical compounds created in its corporate laboratories. Working with a chemist who serves as a sort of “librarian” to this collection, Kalin began by testing 50,000 compounds on biological samples arrayed in 96-well plates, which look like miniature high-tech ice-cube trays.

As tray after tray fed into the screening equipment, an automated process measured two important factors. First, did the compound force FoxM1 proteins out of the cell nucleus? Second, did the compound harm the cell? Kalin ended up with around 15 chemical compounds that deleted FoxM1 without appearing to cause harm and she is currently running the most promising candidates through a gauntlet of experimental tests.

“Right now, we are working with three compounds,” Kalin says. “We started with 15 and we tried them in cell cultures first and then in mouse models next and we are kind of zooming in on the most efficient.”

One day, one of those compounds might prove effective enough to move into development and clinical trials. For now, the research contributes to a better understanding of how our genes affect our sometimes fragile bodies.

“I want to solve these questions right away,” Kalin says. “But I can’t. We take each step at a time. We’re not sprinters. We’re marathoners.”

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