Dr. Francis Collins
Seven Questions for a Rare Disease Warrior
Posted on by Dr. Francis Collins
Credit: National Disease Research Interchange, Philadelphia
Tomorrow is Rare Disease Day at NIH, marking the 12th year that this annual event has been held on the NIH campus. Similar gatherings have been organized independently around the world this week, all to raise awareness for the nearly 7,000 rare diseases, some affecting just a few dozen people. But, collectively, rare diseases are hardly rare. One in 10 Americans has a rare disease (defined as affecting 200,000 or fewer individuals in the US), and about half are children. Without needed treatments, about 30 percent of these children will die by age 5.
To join everyone in raising awareness, I wanted to feature on my blog a unique perspective about rare diseases, and David Fajgenbaum certainly has one. Fajgenbaum is an immunologist and NIH grantee at the Perelman School of Medicine, University of Pennsylvania, Philadelphia. When Fajgenbaum isn’t running studies or clinical trials, he must remain vigilant of his own health. Fajgenbaum has a rare disease called idiopathic multicentric Castleman disease (iMCD), and this devastating condition, which emerged while he was in medical school, nearly claimed his life several times.
Now 34 years old and in a long remission, Fajgenbaum can discuss rare diseases as a doctor, as a patient, as a researcher, and as an advocate. His personal journey, published in his recent book Chasing My Cure, is a gripping read. Fajgenbaum was kind enough to answer a few of my questions on rare diseases and share some of his lessons learned.
The last time that I saw you, David, you looked great. How long have you been in remission?
I have been in remission for 73.83 months. I say 73.83, because I know that I can’t round up—I may relapse tomorrow. But I also refuse to round down because so many colleagues and I have worked so hard for every day of remission for me and other patients with my disease.
For me, every day is particularly special, because I never thought that I would be alive this long. As you know, I became deathly ill during medical school in 2010 and even had my last rites read to me when my doctors didn’t think I would survive. I was eventually diagnosed with idiopathic multicentric Castleman disease (iMCD), which is like a deadly cross between cancer and autoimmunity. Chemotherapy saved my life, but I would go on to have four near-death relapses.
After one of those relapses, I got out of the hospital and dedicated my life to conducting iMCD research and co-founded the Castleman Disease Collaborative Network (CDCN). Later, I identified a particular cellular pathway called mTOR that was highly active in my samples. I began testing on myself an mTOR inhibitor [sirolimus]—developed 30 years before and approved for kidney transplantation but never considered for iMCD. It’s this drug that has kept me in remission for the last 73.83 months and helped other people. During this time, I’ve been able to marry my wife, have a daughter, help launch a new center at Penn specializing in rare diseases, and write a book to share my personal journey with others.
As a physician-scientist and as a person with a rare disease, what have you learned about the biomedical research process?
I’ve learned so much, but I’d like to highlight three lessons in particular. First, we must leverage all perspectives to prioritize research and give us the best chance of translating research into meaningful breakthroughs. The traditional approach to rare disease research involves a subset of researchers within a rare disease field submitting their best ideas for funding and a panel selecting the best applicant.
Through the CDCN, we’ve spearheaded a new approach called the Collaborative Network Approach, where we crowdsource research questions from the entire community of patients, physicians, and researchers (not just a subset of researchers) and then recruit the best researchers in the world (not just from within the Castleman disease field) to perform the prioritized studies. We’re now working to improve and spread this approach to other diseases.
Second, collaboration between all players is critical. Patient advocacy groups are uniquely positioned to serve as the glue between all stakeholders. Researchers and physicians need to share ideas, data, and samples with one another. Patients need to be actively involved in research question prioritization and study design. Biopharma and the Food and Drug Administration (FDA) need to be engaged early in the process of research discoveries and drug development.
Third, we must leverage all 1,500-plus, existing FDA-approved drugs to help as many patients without any options as quickly as possible. As you know, less than 5 percent of the nearly 7,000 rare diseases have an FDA-approved therapy, but many diseases share similar cellular and genetic defects that could make them susceptible to the same drugs. I’m literally alive today thanks to a drug developed for another disease. How many of the drugs approved for one disease may be effective for many of the 7,000 diseases without any? I don’t know the answer, but I hope we can begin to address this important question and incentivize repurposing.
In your experience, how can people with rare diseases help to advance progress for their conditions?
There is so much work to be done for so many rare diseases. Sometimes it can feel so overwhelming and like “what can I really do?”
But I’ve learned that there are so many ways that we can each contribute and so many incredible examples of advocates who have made a difference for themselves and those that they love. Cystic fibrosis and chordoma are just two of many examples where patient-advocates have been critical partners in transforming their diseases.
People with rare diseases can raise funds for research. Every dollar truly counts. We can work with existing organizations for our disease to ensure that those funds are distributed as efficiently and effectively as possible. If there are major gaps within our rare disease fields that aren’t being addressed by existing organizations, we can start new rare disease organizations (but we should try to avoid this whenever possible). We can contribute samples and data towards research, participate in clinical trials, and share with other patients about our experiences. We can advocate for new drug development and repurposing already-FDA approved drugs for our diseases.
What would you tell other researchers who are studying rare diseases?
I would tell other rare disease researchers that you are doing such important work. You give us hope that a treatment can be identified that will change our lives. It’s an incredible responsibility and incredibly stressful. There are unfortunately far too many scientific questions and diseases with major unmet need for any of us to compete over the use of samples and data. We have to share these within our fields. And we must also work together across rare diseases. We can’t continue to reinvent the wheel; we must share learnings with one another
I enjoyed doing the CastleMan Warrior Flex with you. Tell us more about what it represents?
Doing the CastleMan Warrior Flex with you is one of my favorite pictures. In fact, it’s hanging up in my office.
Castleman disease was named after Dr. Benjamin Castleman, who first described our disease in 1954. We have repurposed the “Castleman” name to be a “CastleMan Warrior” (below is our cartoon mascot). We do the “CastleMan Warrior” Flex to raise awareness for Castleman disease and rare diseases generally—we’re all warriors in the rare disease space.
What are your future plans as a rare disease advocate and as a researcher?
We’ve made a lot of progress for Castleman disease: we’ve advanced our findings about mTOR towards a clinical trial, gained approval for the treatment siltuximab for iMCD, developed diagnostic criteria and treatment guidelines, and invested about $1.5 million into Castleman disease research, which has led to over $7 million in additional funding from other sources.
But we still have important work ahead of us. The treatments sirolimus and siltuximab work for only a portion of all iMCD patients. We need to identify more effective treatments for all forms of Castleman disease.
I will continue to study Castleman disease and other diseases at the intersection of autoimmunity and oncology to gain insights into how the immune system works in myriad diseases. In parallel, I will continue to advocate for the adoption of the “Collaborative Network Approach” to crowdsource all stakeholder perspectives as well as for new models for drug repurposing.
Any other issues that you’d like to address?
I feel a responsibility to share with the world the lessons that I’ve learned about life from nearly dying five times. This is a major reason that I wrote my book.
One lesson that I think about a lot is related to my growing up playing football. Some of my games were extended into an overtime period to decide the outcome. In overtime, every second counts and you’re totally focused on what’s important. I’ve lived with that exact same feeling ever since I had my last rites read to me.
I’ve also learned that humor can be incredibly powerful. You may think that a good laugh may be the last thing that you’d want to do when you’re dying in the ICU. But laughing with the people that I love actually helped me feel like I could transcend my illness, and it helped to connect us.
My greatest regrets on my deathbed were not things that I had done or said. I regretted what I didn’t do or didn’t say and that I would no longer be able to do. I now follow the motto: “Think It, Do It.” In other words, we should reflect on what we’re hoping for and then turn our hopes into action.
Finally, I’ve learned that it really takes a strong team to make a difference in the world, especially against diseases. If it was just me on my own, we would have made less than 1 percent of the progress that’s been achieved. I hope that all rare disease warriors will join together into strong teams, armies even, and make a difference in the world.
Links:
Multicentric Castleman Disease (Genetic and Rare Diseases Information Center/NIH)
Castleman Disease Collaborative Network (Paso Robles, CA)
His Doctors Were Stumped. Then He Took Over (New York Times, February 4, 2017)
Video: Chasing My Cure: Dr. David Fajgenbaum’s Lessons From His Rare Disease And On Finding Cures For Others (Exponential Medicine, November 4, 2019)
Rare Disease Day at NIH 2020 (National Center for Advancing Translational Sciences/NIH)
Early Riser or Night Owl? New Study May Help to Explain the Difference
Posted on by Dr. Francis Collins
Credit: Clarisse Ricci, University of California, San Diego
Some people are early risers, wide awake at the crack of dawn. Others are night owls who can’t seem to get to bed until well after midnight and prefer to sleep in. Why is this? An NIH-funded team has some new clues based on evidence showing how a molecular “switch” wired into the biological clocks of extreme early risers leads them to operate on a daily cycle of about 20 hours instead of a full 24-hour, or circadian (Latin for “about a day”), cycle [1].
These new atomic-level details, shared from fruit flies to humans, may help to explain how more subtle clock variations predispose people to follow different sleep patterns. They also may lead to new treatments designed to reset the clock in people struggling with sleep disorders, jet lag, or night-shift work.
This work, published recently in the journal eLIFE, comes from Carrie Partch, University of California, Santa Cruz, and her colleagues at Duke-NUS Medical School in Singapore and the University of California, San Diego. It builds on decades of research into biological clocks, which help to control sleeping and waking, rest and activity, fluid balance, body temperature, cardiac rate, oxygen consumption, and even the secretions of endocrine glands.
These clocks, found in cells and tissues throughout the body, are composed of specialized sets of proteins. They interact in specific ways to regulate transcription of about 15 percent of the genome over a 24-hour period. All this interaction helps to align waking hours and other aspects of our physiology to the 24-hour passage of day and night.
In the latest paper, Partch and her colleagues focused on two core clock components: an enzyme known as casein kinase 1 (CK1) and a protein called PERIOD. Clock-altering mutations in CK1 and PERIOD have been known for many years. In fact, CK1 was discovered in studies of golden hamsters more than 20 years ago after researchers noticed one hamster that routinely woke up much earlier than the others [2,3].
It turns out that the timing of biological clocks is strongly influenced by the rise and fall of the PERIOD protein. This daily oscillation normally takes place over 24 hours, but that’s where CK1 enters the picture. The enzyme adjusts PERIOD levels by chemically modifying the protein at one of two sites, thereby adjusting its stability. When one site is modified, it keeps the protein protected and stable. At the other site, it leaves it unprotected and degradable.
Many of these details had been worked out over the years. But, Partch wanted to drill even deeper to answer an essential question: Why does this process normally take 24 hours, which is remarkably slow biochemically? And, what changes in those whose daily cycle gets cut far short?
To find out, her team performed a series of protein structure and biochemical analyses of the CK1 mutation originally found in hamsters, along with several other clock-altering versions of the enzyme found in organisms ranging from flies to humans. What they’ve discovered is a portion of CK1 acts as a switch. When this switch functions normally, it generates a near-perfect 24-hour cycle by keeping PERIOD’s stability just right. In this case, people easily and correctly align their internal clocks to the daily coming and going of daylight.
If the switch favors a faster breakdown of the protein, the daily cycle grows shorter and less tightly bound to daylight. For these early risers, it’s a constant struggle to adjust to life in a 24-hour world. Though they try to get in sync, these early risers are never able to catch up. Conversely, a switch that favors a slower breakdown will lengthen the clock, predisposing some to be night owls.
Such shifts in clock timing can arise from alterations either to the CK1 enzyme or the PERIOD protein. In fact, people with an inherited sleep disorder called Familial Advanced Sleep Phase Syndrome carry a mutation in the PERIOD protein at one of the places that CK1 modifies. The new work shows that this change makes PERIOD more stable by interfering with the enzyme’s ability to mark the protein for degradation.
One thing that makes the CK1 enzyme so fascinating is that it’s extremely ancient. A nearly identical version of the enzyme to the one in humans and hamsters can be found in single-celled green algae! It’s clear that this enzyme and its function in biological clocks is, evolutionarily speaking, rather special. And at one level, that makes total sense—our planet has operated on a 24-hour clock for the entire span of evolutionary time.
The versions of CK1 that Partch’s team studied here are rare in people. She now plans to study other variations that turn up in humans much more often.
Her discoveries are sure to offer a fascinating view on these internal clocks and, pardon the pun, how they make us all tick. She hopes they’ll lead to new ways to adjust the clock in those with sleep disorders and even the means to reset the clock in people who regularly travel overseas or work the night shift.
Ultimately, Partch would like to tap into the crosstalk between biological clocks and the ability of cells to repair their DNA. She wants to see if clock disruptions have any implications for cancer susceptibility. And yes, now’s a good time to find out the answer.
References:
[1] Casein kinase 1 dynamics underlie substrate selectivity and the PER2 circadian phosphoswitch. Philpott JM, Narasimamurthy R, Ricci CG, Freeberg AM, Hunt SR, Yee LE, Pelofsky RS, Tripathi S, Virshup DM, Partch CL. eLIFE. 2020 Feb 11;9.
[2] A mutation of the circadian system in golden hamsters. Ralph MR, Menaker M. Science. 1988 Sep 2;241(4870):1225-7.
[3] Positional syntenic cloning and functional characterization of the mammalian circadian mutation tau. Lowrey PL, Shimomura K, Antoch MP, Yamazaki S, Zemenides PD, Ralph MR, Menaker M, Takahashi JS. Science. 2000 Apr 21;288(5465):483-92.
Links:
Circadian Rhythms (National Institute of General Medical Sciences/NIH)
Advanced Sleep Phase Syndrome, Familial (Genetic and Rare Disease Center/NIH)
Partch Lab (University of California, Santa Cruz)
NIH Support: National Institute of General Medical Sciences; Office of the Director
Letting Sleeping Dogs Lie
Posted on by Dr. Francis Collins
Tackling Fibrosis with Synthetic Materials
Posted on by Dr. Francis Collins
When injury strikes a limb or an organ, our bodies usually heal quickly and correctly. But for some people, the healing process doesn’t shut down properly, leading to excess fibrous tissue, scarring, and potentially life-threatening organ damage.
This permanent scarring, known as fibrosis, can occur in almost every tissue of the body, including the heart and lungs. With support from a 2019 NIH Director’s New Innovator Award, April Kloxin is applying her expertise in materials science and bioengineering to build sophisticated fibrosis-in-a-dish models for unraveling this complex process in her lab at the University of Delaware, Newark.
Though Kloxin is interested in all forms of fibrosis, she’s focusing first on the incurable and often-fatal lung condition called idiopathic pulmonary fibrosis (IPF). This condition, characterized by largely unexplained thickening and stiffening of lung tissue, is diagnosed in about 50,000 people each year in the United States.
IPF remains poorly understood, in part because it often is diagnosed when the disease is already well advanced. Kloxin hopes to turn back the clock and start to understand the disease at an earlier stage, when interventions might be more successful. The key is to develop a model that better recapitulates the complexity and irreversibility of the disease process in people.
Building that better model starts with simulating the meshwork of collagen and other proteins in the extracellular matrix (ECM) that undergird every tissue and organ in the body. The ECM’s interactions with our cells are essential in wound healing and, when things go wrong, also in causing fibrosis.
Kloxin will build three-dimensional hydrogels, crosslinked sponge-like networks of polymers, peptides, and proteins, with structures that more accurately capture the biological complexities of human tissues, including the ECMs within fibrous collagen-rich microenvironments. Her synthetic matrices can be triggered with light to lock in place and stiffen. The matrices also will make it possible to culture the lung’s epithelium, or outermost layer of cells, and connective tissue that surrounds it, to study cellular responses as the model shifts from a healthy and flexible to a stiffened, disease-like state.
Kloxin and her team will also integrate into their model system lung cells that have been engineered to fluoresce or light up under a microscope when the wound-healing program activates. Such fluorescent reporters will allow her team to watch for the first time how different cells and their nearby microenvironment respond as the composition of the ECM changes and stiffens. With this system, she’ll also be able to search for small molecules with the ability to turn off excessive wound healing.
The hope is that what’s learned with her New Innovator Award will lead to fresh insights and ultimately new treatments for this mysterious, hard-to-treat condition. But the benefits could be even more wide-ranging. Kloxin thinks that her findings will have implications for the prevention and treatment of other fibrotic diseases as well.
Links:
Idiopathic Pulmonary Fibrosis (National Heart, Lung, and Blood Institute/NIH)
April Kloxin Group (University of Delaware, Newark)
Kloxin Project Information (NIH RePORTER)
NIH Director’s New Innovator Award (Common Fund)
NIH Support: Common Fund; National Heart, Lung, and Blood Institute
A Global Look at Cancer Genomes
Posted on by Dr. Francis Collins
Cancer is a disease of the genome. It can be driven by many different types of DNA misspellings and rearrangements, which can cause cells to grow uncontrollably. While the first oncogenes with the potential to cause cancer were discovered more than 35 years ago, it’s been a long slog to catalog the universe of these potential DNA contributors to malignancy, let alone explore how they might inform diagnosis and treatment. So, I’m thrilled that an international team has completed the most comprehensive study to date of the entire genomes—the complete sets of DNA—of 38 different types of cancer.
Among the team’s most important discoveries is that the vast majority of tumors—about 95 percent—contained at least one identifiable spelling change in their genomes that appeared to drive the cancer [1]. That’s significantly higher than the level of “driver mutations” found in past studies that analyzed only a tumor’s exome, the small fraction of the genome that codes for proteins. Because many cancer drugs are designed to target specific proteins affected by driver mutations, the new findings indicate it may be worthwhile, perhaps even life-saving in many cases, to sequence the entire tumor genomes of a great many more people with cancer.
The latest findings, detailed in an impressive collection of 23 papers published in Nature and its affiliated journals, come from the international Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium. Also known as the Pan-Cancer Project for short, it builds on earlier efforts to characterize the genomes of many cancer types, including NIH’s The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC).
In these latest studies, a team including more than 1,300 researchers from around the world analyzed the complete genomes of more than 2,600 cancer samples. Those samples included tumors of the brain, skin, esophagus, liver, and more, along with matched healthy cells taken from the same individuals.
In each of the resulting new studies, teams of researchers dug deep into various aspects of the cancer DNA findings to make a series of important inferences and discoveries. Here are a few intriguing highlights:
• The average cancer genome was found to contain not just one driver mutation, but four or five.
• About 13 percent of those driver mutations were found in so-called non-coding DNA, portions of the genome that don’t code for proteins [2].
• The mutations arose within about 100 different molecular processes, as indicated by their unique patterns or “mutational signatures.” [3,4].
• Some of those signatures are associated with known cancer causes, including aberrant DNA repair and exposure to known carcinogens, such as tobacco smoke or UV light. Interestingly, many others are as-yet unexplained, suggesting there’s more to learn with potentially important implications for cancer prevention and drug development.
• A comprehensive analysis of 47 million genetic changes pieced together the chronology of cancer-causing mutations. This work revealed that many driver mutations occur years, if not decades, prior to a cancer’s diagnosis, a discovery with potentially important implications for early cancer detection [5].
The findings represent a big step toward cataloging all the major cancer-causing mutations with important implications for the future of precision cancer care. And yet, the fact that the drivers in 5 percent of cancers continue to remain mysterious (though they do have RNA abnormalities) comes as a reminder that there’s still a lot more work to do. The challenging next steps include connecting the cancer genome data to treatments and building meaningful predictors of patient outcomes.
To help in these endeavors, the Pan-Cancer Project has made all of its data and analytic tools available to the research community. As researchers at NIH and around the world continue to detail the diverse genetic drivers of cancer and the molecular processes that contribute to them, there is hope that these findings and others will ultimately vanquish, or at least rein in, this Emperor of All Maladies.
References:
[1] Pan-Cancer analysis of whole genomes. ICGC/TCGA Pan-Cancer Analysis of Whole Genomes Consortium. Nature. 2020 Feb;578(7793):82-93.
[2] Analyses of non-coding somatic drivers in 2,658 cancer whole genomes. Rheinbay E et al; PCAWG Consortium. Nature. 2020 Feb;578(7793):102-111.
[3] The repertoire of mutational signatures in human cancer. Alexandrov LB et al; PCAWG Consortium. Nature. 2020 Feb;578(7793):94-101.
[4] Patterns of somatic structural variation in human cancer genomes. Li Y et al; PCAWG Consortium. Nature. 2020 Feb;578(7793):112-121.
[5] The evolutionary history of 2,658 cancers. Gerstung M, Jolly C, Leshchiner I, Dentro SC et al; PCAWG Consortium. Nature. 2020 Feb;578(7793):122-128.
Links:
The Genetics of Cancer (National Cancer Institute/NIH)
Precision Medicine in Cancer Treatment (NCI)
The Cancer Genome Atlas Program (NIH)
NCI and the Precision Medicine Initiative (NCI)
NIH Support: National Cancer Institute, National Human Genome Research Institute
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