Confusing cancer to kill it

Kipps

Thomas Kipps, MD, PhD: Photo courtesy UC San Diego

Confusion is not a state of mind that we usually seek out. Being bewildered is bad enough when it happens naturally, so why would anyone actively pursue it? But now some researchers are doing just that, using confusion to not just block a deadly blood cancer, but to kill it.

Today the CIRM Board approved an investment of $18.29 million to Dr. Thomas Kipps and his team at UC San Diego to use a one-two combination approach that we hope will kill Chronic Lymphocytic Leukemia (CLL).

This approach combines two therapies, cirmtuzumab (a monoclonal antibody developed with CIRM funding, hence the name) and Ibrutinib, a drug that has already been approved by the US Food and Drug Administration (FDA) for patients with CLL.

As Dr. Maria Millan, our interim President and CEO, said in a news release, the need for a new treatment is great.

“Every year around 20,000 Americans are diagnosed with CLL. For those who have run out of treatment options, the only alternative is a bone marrow transplant. Since CLL afflicts individuals in their 70’s who often have additional medical problems, bone marrow transplantation carries a higher risk of life threatening complications. The combination approach of  cirmtuzumab and Ibrutinib seeks to offer a less invasive and more effective alternative for these patients.”

Ibrutinib blocks signaling pathways that leukemia cells need to survive. Disrupting these pathways confuses the leukemia cell, leading to its death. But even with this approach there are cancer stem cells that are able to evade Ibrutinib. These lie dormant during the therapy but come to life later, creating more leukemia cells and causing the cancer to spread and the patient to relapse. That’s where cirmtuzumab comes in. It works by blocking a protein on the surface of the cancer stem cells that the cancer needs to spread.

It’s hoped this one-two punch combination will kill all the cancer cells, increasing the number of patients who go into complete remission and improve their long-term cancer control.

In an interview with OncLive, a website focused on cancer professionals, Tom Kipps said Ibrutinib has another advantage for patients:

“The patients are responding well to treatment. It doesn’t seem like you have to worry about stopping therapy, because you’re not accumulating a lot of toxicity as you would with chemotherapy. If you administered chemotherapy on and on for months and months and years and years, chances are the patient wouldn’t tolerate that very well.”

The CIRM Board also approved $5 million for Angiocrine Bioscience Inc. to carry out a Phase 1 clinical trial testing a new way of using cord blood to help people battling deadly blood disorders.

The standard approach for this kind of problem is a bone marrow transplant from a matched donor, usually a family member. But many patients don’t have a potential donor and so they often have to rely on a cord blood transplant as an alternative, to help rebuild and repair their blood and immune systems. However, too often a single cord blood donation does not have enough cells to treat an adult patient.

Angiocrine has developed a product that could help get around that problem. AB-110 is made up of cord blood-derived hematopoietic stem cells (these give rise to all the other types of blood cell) and genetically engineered endothelial cells – the kind of cell that lines the insides of blood vessels.

This combination enables the researchers to take cord blood cells and greatly expand them in number. Expanding the number of cells could also expand the number of patients who could get these potentially life-saving cord blood transplants.

These two new projects now bring the number of clinical trials funded by CIRM to 35. You can read about the other 33 here.

 

 

 

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New research suggests taking a daily dose of vitamin C could prevent leukemia

Did you take your vitamins today? It’s not always easy to remember with such busy lives, but after you read this blog, you’ll be sure to make vitamins part of your daily routine if you haven’t already!

Two recent studies, published in the journals Nature and Cell, reported that vitamin C has a direct impact on the function of blood forming, or hematopoietic stem cells, and can be used to protect mice from getting a blood cancer called leukemia.

Science reporter Bradley Fikes compared the findings of the two studies yesterday in the San Diego Union Tribune. According to Fikes, the Nature study, which was conducted by scientists at UT Southwestern, “found that human and mouse hematopoietic stem cells absorb unusually large amounts of vitamin C. When the cells were depleted of vitamin C, they were more likely to turn into leukemia cells.”

As for the Cell study, scientists from NYU Langone Health “found that high doses of vitamin C can cause leukemic cells to die, potentially making it a useful and safe chemotherapy agent.” For more details on this particular study, see our blog from last week and the video below.

Dr. Benjamin Neel, director of NYU Langone’s Perlmutter Cancer Center, discusses how vitamin C may “tell” faulty stem cells in the bone marrow to mature and die normally, instead of multiplying to cause blood cancers.

Vitamin C levels are crucial for preventing leukemia

The common factor between the two studies is a gene called Tet2, which is turned on in blood stem cells and protects them from over-proliferating and acquiring genetic mutations that transform them into leukemia cells. If one copy of the Tet2 gene is genetically mutated, treating blood stem cells with vitamin C can make up for this partial loss in Tet2 function. However, if both copies of Tet2 are mutated, its protective functions are completely lost and blood stem cells can turn cancerous.

Fikes reached out to Sean Morrison, senior author on the Nature study, for an explanation about the relationship between vitamin C and Tet2, and how it can be leveraged to prevent or treat leukemia:

Sean Morrison

“The Cell study showed that high doses of vitamin C can compensate for Tet2 mutations, restoring normal function, Morrison said. Usually, transformation of normal cells into leukemic cells is irreversible, but the study demonstrated that’s not true when the leukemia is driven by Tet2 mutations.”

“The Nature study demonstrated that vitamin C is a limiting factor in the proper function of Tet2, Morrison said. People have two copies of the gene, one from each parent. When one of the genes is disabled, it’s important to take the full recommended dose of vitamin C so the remaining gene can exert its full tumor-suppressing effect.”

Before you place your bulk order of vitamin C on amazon, you should be aware that Morrison and his colleagues found that giving mice super doses of the supplement failed to further reduce their risk of getting leukemia. Thus, it seems that having the right levels of vitamin C in blood stem cells and healthy copies of the Tet2 gene are vital for preventing leukemia.

Vitamin C, a panacea for cancer?

These two studies raise important questions. Do vitamin C levels play a role in the development of other cancer cells and could this supplement be used as a treatment for other types of cancers?

Since the 1970’s, scientists (including the famous American scientist Linus Pauling) and doctors have pursued vitamin C as a potential cancer treatment. Early stage research revealed that vitamin C plays a role in slowing the growth of various types of cancer cells including prostate, colon and brain cancer cells. More recently, some of this research has progressed to clinical trials that are testing high-doses of vitamin C either by itself or in combination with chemotherapy drugs in cancer patients. Some of these trials have reported an improved quality of life and increased average survival time in patients, but more research and trials are necessary to determine whether vitamin C is a truly effective anti-cancer therapy.

Now that Morrison and his team have a better understanding of how vitamin C levels affect cancer risk, they plan to address some of these outstanding questions in future studies.

“Our data also suggest that probably not all cancers are increased by vitamin C depletion. We particularly would predict that certain leukemias would be increased in the absence of vitamin C. We’re collaborating with the Centers for Disease Control right now to look more carefully at the epidemiological data that have been collected over decades, to understand more precisely which cancers are at increased risk in people that have lower levels of vitamin C.”

CIRM weekly stem cell roundup: stomach bacteria & cancer; vitamin C may block leukemia; stem cells bring down a 6’2″ 246lb football player

gastric

This is what your stomach glands looks like from the inside:  Credit: MPI for Infection Biology”

Stomach bacteria crank up stem cell renewal, may be link to gastric cancer (Todd Dubnicoff)

The Centers for Disease Control and Prevention estimate that two-thirds of the world’s population is infected with H. pylori, a type of bacteria that thrives in the harsh acidic conditions of the stomach. Data accumulated over the past few decades shows strong evidence that H. pylori infection increases the risk of stomach cancers. The underlying mechanisms of this link have remained unclear. But research published this week in Nature suggests that the bacteria cause stem cells located in the stomach lining to divide more frequently leading to an increased potential for cancerous growth.

Tumors need to make an initial foothold in a tissue in order to grow and spread. But the cells of our stomach lining are replaced every four days. So, how would H. pylori bacterial infection have time to induce a cancer? The research team – a collaboration between scientists at the Max Planck Institute in Berlin and Stanford University – asked that question and found that the bacteria are also able to penetrate down into the stomach glands and infect stem cells whose job it is to continually replenish the stomach lining.

Further analysis in mice revealed that two groups of stem cells exist in the stomach glands – one slowly dividing and one rapidly dividing population. Both stem cell populations respond similarly to an important signaling protein, called Wnt, that sustains stem cell renewal. But the team also discovered a second key stem cell signaling protein called R-spondin that is released by connective tissue underneath the stomach glands. H. pylori infection of these cells causes an increase in R-spondin which shuts down the slowly dividing stem cell population but cranks up the cell division of the rapidly dividing stem cells. First author, Dr. Michal Sigal, summed up in a press release how these results may point to stem cells as the link between bacterial infection and increased risk of stomach cancer:

“Since H. pylori causes life-long infections, the constant increase in stem cell divisions may be enough to explain the increased risk of carcinogenesis observed.”

vitamin-c-1200x630

Vitamin C may have anti-blood cancer properties

Vitamin C is known to have a number of health benefits, from preventing scurvy to limiting the buildup of fatty plaque in your arteries. Now a new study says we might soon be able to add another benefit: it may be able to block the progression of leukemia and other blood cancers.

Researchers at the NYU School of Medicine focused their work on an enzyme called TET2. This is found in hematopoietic stem cells (HSCs), the kind of stem cell typically found in bone marrow. The absence of TET2 is known to keep these HSCs in a pre-leukemic state; in effect priming the body to develop leukemia. The researchers showed that high doses of vitamin C can prevent, or even reverse that, by increasing the activity level of TET2.

In the study, in the journal Cell, they showed how they developed mice that could have their levels of TET2 increased or decreased. They then transplanted bone marrow with low levels of TET2 from those mice into healthy, normal mice. The healthy mice started to develop leukemia-like symptoms. However, when the researchers used high doses of vitamin C to restore the activity levels of TET2, they were able to halt the progression of the leukemia.

Now this doesn’t mean you should run out and get as much vitamin C as you can to help protect you against leukemia. In an article in The Scientist, Benjamin Neel, senior author of the study, says while vitamin C does have health benefits,  consuming large doses won’t do you much good:

“They’re unlikely to be a general anti-cancer therapy, and they really should be understood based on the molecular understanding of the many actions vitamin C has in cells.”

However, Neel says these findings do give scientists a new tool to help them target cells before they become leukemic.

Jordan reed

Bad toe forces Jordan Reed to take a knee: Photo courtesy FanRag Sports

Toeing the line: how unapproved stem cell treatment made matters worse for an NFL player  

American football players are tough. They have to be to withstand pounding tackles by 300lb men wearing pads and a helmet. But it wasn’t a crunching hit that took Washington Redskins player Jordan Reed out of the game; all it took to put the 6’2” 246 lb player on the PUP (Physically Unable to Perform) list was a little stem cell injection.

Reed has had a lingering injury problem with the big toe on his left foot. So, during the off-season, he thought he would take care of the issue, and got a stem cell injection in the toe. It didn’t quite work the way he hoped.

In an interview with the Richmond Times Dispatch he said:

“That kind of flared it up a bit on me. Now I’m just letting it calm down before I get out there. I’ve just gotta take my time, let it heal and strengthen up, then get back out there.”

It’s not clear what kind of stem cells Reed got, if they were his own or from a donor. What is clear is that he is just the latest in a long line of athletes who have turned to stem cells to help repair or speed up recovery from an injury. These are treatments that have not been approved by the Food and Drug Administration (FDA) and that have not been tested in a clinical trial to make sure they are both safe and effective.

In Reed’s case the problem seems to be a relatively minor one; his toe is expected to heal and he should be back in action before too long.

Stem cell researcher and avid blogger Dr. Paul Knoepfler wrote he is lucky, others who take a similar approach may not be:

“Fortunately, it sounds like Reed will be fine, but some people have much worse reactions to unproven stem cells than a sore toe, including blindness and tumors. Be careful out there!”

One man’s journey with leukemia has turned into a quest to make bone marrow stem cell transplants safer

Dr. Lukas Wartman in his lab in March 2011 (left), before he developed chronic graft-versus-host disease, and last month at a physical therapy session (right). (Photo by Whitney Curtis for Science Magazine)

I read a story yesterday in Science Magazine that really stuck with me. It’s about a man who was diagnosed with leukemia and received a life-saving stem cell transplant that is now threatening his health.

The man is name Lukas Wartman and is a doctor at Washington University School of Medicine in St. Louis. He was first diagnosed with a type of blood cancer called acute lymphoblastic leukemia (ALL) in 2003. Since then he has taken over 70 drugs and undergone two rounds of bone marrow stem cell transplants to fight off his cancer.

The first stem cell transplant was from his brother, which replaced Wartman’s diseased bone marrow, containing blood forming stem cells and immune cells, with healthy cells. In combination with immunosuppressive drugs, the transplant worked without any complications. Unfortunately, a few years later the cancer returned. This time, Wartman opted for a second transplant from an unrelated donor.

While the second transplant and cancer-fighting drugs have succeeded in keeping his cancer at bay, Wartman is now suffering from something equally life threatening – a condition called graft vs host disease (GVHD). In a nut shell, the stem cell transplant that cured him of cancer and saved his life is now attacking his body.

GVHD, a common side effect of bone marrow transplants

GVHD is a disease where donor transplanted immune cells, called T cells, expand and attack the cells and tissues in your body because they see them as foreign invaders. GVHD occurs in approximately 50% of patients who receive bone marrow, peripheral blood or cord blood stem cell transplants, and typically affects the skin, eyes, mouth, liver and intestines.

The main reason why GVHD is common following blood stem cell transplants is because many patients receive transplants from unrelated donors or family members who aren’t close genetic matches. Half of patients who receive these types of transplants develop an acute form of GVHD within 100 days of treatment. These patients are put on immunosuppressive steroid drugs with the hope that the patient’s body will eventually kill off the aggressive donor T cells.

This was the case for Wartman after the first transplant from his brother, but the second transplant from an unrelated donor eventually caused him to develop the chronic form of GVHD. Wartman is now suffering from weakened muscles, dry eyes, mouth sores and skin issues as the transplanted immune cells slowly attack his body from within. Thankfully, his major organs are still untouched by GVHD, but Wartman knows it could be only a matter of time before his condition worsens.

Dr. Lukas Wartman has to use eye drops every 20 minutes to deal with dry eyes caused by GVHD. (Photo by Whitney Curtis for Science Magazine)

Hope for GVHD sufferers

Wartman along with other GVHD patients are basically guinea pigs in a field where effective drugs are still being developed and tested. Many of these patients, including Wartman, have tried many unproven treatments or drugs for other disease conditions in desperate hope that something will work. It’s a situation that is heartbreaking not only for the patient but also for their families and doctors.

There is hope for GVHD patients however. Science Magazine mentioned two promising drugs for GVHD, ibrutinib and ruxolitinib. Both received breakthrough therapy designation from the US Food and Drug Administration and could be the first approved treatments for GVHD.

Another promising therapy is called Prochymal. It’s a stem cell therapy developed by former CIRM President and CEO, Dr. Randy Mills, at Osiris Therapeutics. Prochymal is already approved to treat the acute form of GVHD in Canada, and is currently being tested in phase 3 trials in the US in young children and adults.

While CIRM isn’t currently funding clinical trials for GVHD, we are funding a trial out of Stanford University led by Dr. Judy Shizuru that aims to improve the outcome of bone marrow stem cell transplants in patients. Shizuru says that these transplants are “the most powerful form of cell therapy out there, for cancers or deficiencies in blood formation” but they come with their own set of potentially deadly side effects such as GVHD.

Shizuru is testing an antibody drug that blocks a signaling protein called CD117, which sits on the surface of blood stem cells and acts as an elimination signal. By turning off this protein, her team improved the engraftment of bone marrow stem cells in mice that had leukemia and removed their need for chemotherapy treatment. The therapy is in a Phase 1 trial for patients with an immune disease called severe combined immunodeficiency (SCID) who receive bone marrow transplants, but Shizuru said that her hope is the drug could also treat patients with certain cancers or blood diseases.

Advocating for better GVHD treatments

The reason the article in Science Magazine spoke to me is because of the power of Wartman’s story. Wartman’s battle with ALL and now GVHD has transformed him into one of the strongest patient voices advocating for the development of new GVHD treatments. Jon Cohen, the author of the Science Magazine article, explained:

“The urgency of his case has turned Wartman into one of the world’s few patients who advocate for GVHD research, prevention, and treatment. ‘Most people it affects suffer quietly,” says Wartman. ‘They’re grateful they’re alive, and they’re beaten down. It’s the paradox of being cured and dying of the cure. Even if you can get past that, you don’t have the energy to advocate, and that’s really tragic.’”

Patients like Wartman are an inspiration not only to other people with GVHD, but also to funding agencies and scientists working to advance GVHD research towards a cure. We don’t want these patients to suffer quietly. Wartman’s story is an important reminder that there’s a lot more work to do to make bone marrow transplants safer – so that they save lives without later putting those lives at risk.

Don’t Be Afraid: High school stem cell researcher on inspiring girls to pursue STEM careers

As part of our CIRM scholar blog series, we’re featuring the research and career accomplishments of CIRM funded students.

Shannon Larsuel

Shannon Larsuel is a high school senior at Mayfield Senior School in Pasadena California. Last summer, she participated in Stanford’s CIRM SPARK high school internship program and did stem cell research in a lab that studies leukemia, a type of blood cancer. Shannon is passionate about helping people through research and medicine and wants to become a pediatric oncologist. She is also dedicated to inspiring young girls to pursue STEM (Science, Technology, Engineering, and Mathematics) careers through a group called the Stem Sisterhood.

I spoke with Shannon to learn more about her involvement in the Stem Sisterhood and her experience in the CIRM SPARK program. Her interview is below.


Q: What is the Stem Sisterhood and how did you get involved?

SL: The Stem Sisterhood is a blog. But for me, it’s more than a blog. It’s a collective of women and scientists that are working to inspire other young scientists who are girls to get involved in the STEM field. I think it’s a wonderful idea because girls are underrepresented in STEM fields, and I think that this needs to change.

I got involved in the Stem Sisterhood because my friend Bridget Garrity is the founder. This past summer when I was at Stanford, I saw that she was doing research at Caltech. I reconnected with her and we started talking about our summer experiences working in labs. Then she asked me if I wanted to be involved in the Stem Sisterhood and be one of the faces on her website. She took an archival photo of Albert Einstein with a group of other scientists that’s on display at Caltech and recreated it with a bunch of young women who were involved in the STEM field. So I said yes to being in the photo, and I’m also in the midst of writing a blog post about my experience at Stanford in the SPARK program.

Members of The Stem Sisterhood

Q: What does the Stem Sisterhood do?

SL: Members of the team go to elementary schools and girl scout troop events and speak about science and STEM to the young girls. The goal is to inspire them to become interested in science and to teach them about different aspects of science that maybe are not that well known.

The Stem Sisterhood is based in Los Angeles. The founder Bridget wants to expand the group, but so far, she has only done local events because she is a senior in high school. The Stem Sisterhood has an Instagram account in addition to their blog. The blog is really interesting and features interviews with women who are in science and STEM careers.

Q: How has the Stem Sisterhood impacted your life?

SL: It has inspired me to reach out to younger girls more about science. It’s something that I am passionate about, and I’d like to pursue a career in the medical field. This group has given me an outlet to share that passion with others and to hopefully change the face of the STEM world.

Q: How did you find out about the CIRM SPARK program?

SL: I knew I wanted to do a science program over the summer, but I wasn’t sure what type. I didn’t know if I wanted to do research or be in a hospital. I googled science programs for high school seniors, and I saw the one at Stanford University. It looked interesting and Stanford is obviously a great institution. Coming from LA, I was nervous that I wouldn’t be able to get in because the program had said it was mostly directed towards students living in the Bay Area. But I got in and I was thrilled. So that’s basically how I heard about it, because I googled and found it.

Q: What was your SPARK experience like?

SL: My program was incredible. I was a little bit nervous and scared going into it because I was the only high school student in my lab. As a high school junior going into senior year, I was worried about being the youngest, and I knew the least about the material that everyone in the lab was researching. But my fears were quickly put aside when I got to the lab. Everyone was kind and helpful, and they were always willing to answer my questions. Overall it was really amazing to have my first lab experience be at Stanford doing research that’s going to potentially change the world.

Shannon working in the lab at Stanford.

I was in a lab that was using stem cells to characterize a type of leukemia. The lab is hoping to study leukemia in vitro and in vivo and potentially create different treatments and cures from this research. It was so cool knowing that I was doing research that was potentially helping to save lives. I also learned how to work with stem cells which was really exciting. Stem cells are a new advancement in the science world, so being able to work with them was incredible to me. So many students will never have that opportunity, and being only 17 at the time, it was amazing that I was working with actual stem cells.

I also liked that the Stanford SPARK program allowed me to see other aspects of the medical world. We did outreach programs in the Stanford community and helped out at the blood drive where we recruited people for the bone marrow registry. I never really knew anything about the registry, but after learning about it, it really interested me. I actually signed up for it when I turned 18. We also met with patients and their families and heard their stories about how stem cell transplants changed their lives. That was so inspiring to me.

Going into the program, I was pretty sure I wanted to be a pediatric oncologist, but after the program, I knew for sure that’s what I wanted to do. I never thought about the research side of pediatric oncology, I only thought about the treatment of patients. So the SPARK program showed me what laboratory research is like, and now that’s something I want to incorporate into my career as a pediatric oncologist.

I learned so much in such a short time period. Through SPARK, I was also able to connect with so many incredible, inspired young people. The students in my program and I still have a group chat, and we text each other about college and what’s new with our lives. It’s nice knowing that there are so many great people out there who share my interests and who are going to change the world.

Stanford SPARK students.

Q: What was your favorite part of the SPARK program?

SL: Being in the lab every day was really incredible to me. It was my first research experience and I was in charge of a semi-independent project where I would do bacterial transformations on my own and run the gels. It was cool that I could do these experiments on my own. I also really loved the end of the summer poster session where all the students from the different SPARK programs came together to present their research. Being in the Stanford program, I only knew the Stanford students, but there were so many other awesome projects that the other SPARK students were doing. I really enjoyed being able to connect with those students as well and learn about their projects.

Q: Why do you want to pursue pediatric oncology?

SL: I’ve always been interested in the medical field but I’ve had a couple of experiences that really inspired me to become a doctor. My friend has a charity that raises money for Children’s Hospital Los Angeles. Every year, we deliver toys to the hospital. The first year I participated, we went to the hospital’s oncology unit and something about it stuck with me. There was one little boy who was getting his chemotherapy treatment. He was probably two years old and he really inspired to create more effective treatments for him and other children.

I also participated in the STEAM Inquiry program at my high school, where I spent two years reading tons of peer reviewed research on immunotherapy for pediatric cancer. Immunotherapy is something that really interests me. It makes sense that since cancer is usually caused by your body’s own mutations, we should be able to use the body’s immune system that normally regulates this to try and cure cancer. This program really inspired me to go into this field to learn more about how we can really tailor the immune system to fight cancer.

Q: What advice do you have for young girls interested in STEM.

SL: My advice is don’t be afraid. I think that sometimes girls are expected to be interested in less intellectual careers. This perception can strike fear into girls and make them think “I won’t be good enough. I’m not smart enough for this.” This kind of thinking is not good at all. So I would say don’t be afraid and be willing to put yourself out there. I know for me, sometimes it’s scary to try something and know you could fail. But that’s the best way to learn. Girls need to know that they are capable of doing anything and if they just try, they will be surprised with what they can do.

Multi-Talented Stem Cells: The Many Ways to Use Them in the Clinic

CIRM kicked off the 2016 International Society for Stem Cell Research (ISSCR) Conference in San Francisco with a public stem cell event yesterday that brought scientists, patients, patient advocates and members of the general public together to discuss the many ways stem cells are being used in the clinic to develop treatments for patients with unmet medical needs.

Bruce Conklin, Gladstone Institutes & UCSF

Bruce Conklin, Gladstone Institutes & UCSF

Bruce Conklin, an Investigator at the Gladstone Institutes and UCSF Professor, moderated the panel of four scientists and three patient advocates. He immediately captured the audience’s attention by showing a stunning video of human heart cells, beating in synchrony in a petri dish. Conklin explained that scientists now have the skills and technology to generate human stem cell models of cardiomyopathy (heart disease) and many other diseases in a dish.

Conklin went on to highlight four main ways that stem cells are contributing to human therapy. First is using stem cells to model diseases whose causes are still largely unknown (like with Parkinson’s disease). Second, genome editing of stem cells is a new technology that has the potential to offer cures to patients with genetic disorders like sickle cell anemia. Third, stem cells are known to secrete healing factors, and transplanting them into humans could be beneficial. Lastly, stem cells can be engineered to attack cancer cells and overcome cancer’s normal way of evading the immune system.

Before introducing the other panelists, Conklin made the final point that stem cell models are powerful because scientists can use them to screen and develop new drugs for diseases that have no treatments or cures. His lab is already working on identifying new drugs for heart disease using human induced pluripotent stem cells derived from patients with cardiomyopathy.

Scientists and Patient Advocates Speak Out

Malin Parmar, Lund University

Malin Parmar, Lund University

The first scientist to speak was Malin Parmar, a Professor at Lund University. She discussed the history of stem cell development for clinical trials in Parkinson’s disease (PD). Her team is launching the first in-human trial for Parkinson’s using cells derived from human pluripotent stem cells in 2016. After Parmar’s talk, John Lipp, a PD patient advocate. He explained that while he might look normal standing in front of the crowd, his PD symptoms vary wildly throughout the day and make it hard for him to live a normal life. He believes in the work that scientists like Parmar are doing and confidently said, “In my lifetime, we will find a stem cell cure for Parkinson’s disease.”

Adrienne Shapiro, Patient Advocate

Adrienne Shapiro, Patient Advocate

The next scientist to speak was UCLA Professor Donald Kohn. He discussed his lab’s latest efforts to develop stem cell treatments for different blood disorder diseases. His team is using gene therapy to modify blood stem cells in bone marrow to treat and cure babies with SCID, also known as “bubble-boy disease”. Kohn also mentioned their work in sickle cell disease (SCD) and in chronic granulomatous disease, both of which are now in CIRM-funded clinical trials. He was followed by Adrienne Shapiro, a patient advocate and mother of a child with SCD. Adrienne gave a passionate and moving speech about her family history of SCD and her battle to help find a cure for her daughter. She said “nobody plans to be a patient advocate. It is a calling born of necessity and pain. I just wanted my daughter to outlive me.”

Henry Klassen (UC Irvine)

Henry Klassen, UC Irvine

Henry Klassen, a professor at UC Irvine, next spoke about blinding eye diseases, specifically retinitis pigmentosa (RP). This disease damages the photo receptors in the back of the eye and eventually causes blindness. There is no cure for RP, but Klassen and his team are testing the safety of transplanting human retinal progenitor cells in to the eyes of RP patients in a CIRM-funded Phase 1/2 clinical trial.

Kristen MacDonald, RP patient

Kristen MacDonald, RP patient

RP patient, Kristen MacDonald, was the trial’s first patient to be treated. She bravely spoke about her experience with losing her vision. She didn’t realize she was going blind until she had a series of accidents that left her with two broken arms. She had to reinvent herself both physically and emotionally, but now has hope that she might see again after participating in this clinical trial. She said that after the transplant she can now finally see light in her bad eye and her hope is that in her lifetime she can say, “One day, people used to go blind.”

Lastly, Catriona Jamieson, a professor and Alpha Stem Cell Clinic director at UCSD, discussed how she is trying to develop new treatments for blood cancers by eradicating cancer stem cells. Her team is conducting a Phase 1 CIRM-funded clinical trial that’s testing the safety of an antibody drug called Cirmtuzumab in patients with chronic lymphocytic leukemia (CLL).

Scientists and Patients need to work together

Don Kohn, Catriona Jamieson, Malin Parmar

Don Kohn, Catriona Jamieson, Malin Parmar

At the end of the night, the scientists and patient advocates took the stage to answer questions from the audience. A patient advocate in the audience asked, “How can we help scientists develop treatments for patients more quickly?”

The scientists responded that stem cell research needs more funding and that agencies like CIRM are making this possible. However, we need to keep the momentum going and to do that both the physicians, scientists and patient advocates need to work together to advocate for more support. The patient advocates in the panel couldn’t have agreed more and voiced their enthusiasm for working together with scientists and clinicians to make their hopes for cures a reality.

The CIRM public event was a huge success and brought in more than 150 people, many of whom stayed after the event to ask the panelists more questions. It was a great kick off for the ISSCR conference, which starts today. For coverage, you can follow the Stem Cellar Blog for updates on interesting stem cell stories that catch our eye.

CIRM Public Stem Cell Event

CIRM Public Stem Cell Event

Stem cell stories that caught our eye: a surprising benefit of fasting, faster way to make iPSCs, unlocking the secret of leukemia cancer cells

Here are some stem cell stories that caught our eye this past week. Some are groundbreaking science, others are of personal interest to us, and still others are just fun.

Fasting

Is fasting the fountain of youth?

Among the many insults our bodies endure in old age is a weakened immune system which leaves the elderly more susceptible to infection. Chemotherapy patients also face the same predicament due to the immune suppressing effects of their toxic anticancer treatments. While many researchers aim to develop drugs or cell therapies to protect the immune system, a University of Southern California research report this week suggests an effective alternative intervention that’s startlingly straightforward: fasting for 72 hours.

The study published in Cell Stem Cell showed that cycles of prolonged fasting in older mice led to a decrease in white blood cells which in turn set off a regenerative burst of blood stem cells. This restart of the blood stem cells replenished the immune system with new white blood cells. In a pilot Phase 1 clinical trial, cancer patients who fasted 72 hours before receiving chemotherapy maintained normal levels of white blood cells.

A look at the molecular level of the process pointed to a decrease in the levels of a protein called PKA in stem cells during the fasting period. In a university press release carried by Science Daily, the study leader, Valter Longo, explained the significance of this finding:

“PKA is the key gene that needs to shut down in order for these stem cells to switch into regenerative mode. It gives the ‘okay’ for stem cells to go ahead and begin proliferating and rebuild the entire system. And the good news is that the body got rid of the parts of the system that might be damaged or old, the inefficient parts, during the fasting. Now, if you start with a system heavily damaged by chemotherapy or aging, fasting cycles can generate, literally, a new immune system.”

In additional to necessary follow up studies, the team is looking into whether fasting could benefit other organ systems besides the immune system. If the data holds up, it could be that regular fasting or direct targeting of PKA could put us on the road to a much more graceful and healthier aging process.

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Faster, cheaper, safer way to use iPS cells

Science, like traffic in any major city, never moves quite as quickly as you would like, but now Japanese researchers are teaming up to develop a faster, and cheaper way of using iPSC’s , pluripotent stem cells that are reprogrammed from adult cells, for transplants.

Part of the beauty of iPSCs is that because those cells came from the patient themselves, there is less risk of rejection. But there are problems with this method. Taking adult cells and turning them into enough cells to treat someone can take a long time. It’s expensive too.

But now researchers at Kyoto University and three other institutions in Japan have announced they are teaming up to change that. They want to create a stockpile of iPSCs that are resistant to immunological rejection, and are ready to be shipped out to researchers.

Having a stockpile of ready-to-use iPSCs on hand means researchers won’t have to wait months to develop their own, so they can speed up their work.

Shinya Yamanaka, who developed the technique to create iPSCs and won the Nobel prize for his efforts, say there’s another advantage with this collaboration. In a news article on Nikkei’s Asian Review he said these cells will have been screened to make sure they don’t carry any potentially cancer-causing mutations.

“We will take all possible measures to look into the safety in each case, and we’ll give the green light once we’ve determined they are sound scientifically. If there is any concern at all, we will put a stop to it.”

CIRM is already working towards a similar goal with our iPSC Initiative.

Unlocking the secrets of leukemia stem cells

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Zombies: courtesy “The Walking Dead”

Any article that has an opening sentence that says “Cancer stem cells are like zombies” has to be worth reading. And a report in ScienceMag  that explains how pre-leukemia white blood cell precursors become leukemia cancer stem cells is definitely worth reading.

The article is about a study in the journal Cell Stem Cell by researchers at UC San Diego. The senior author is Catriona Jamieson:

“In this study, we showed that cancer stem cells co-opt an RNA editing system to clone themselves. What’s more, we found a method to dial it down.”

An enzyme called ADAR1 is known to spur cancer growth by manipulating small pieces of genetic material known as microRNA. Jamieson and her team wanted to track how that was done. They discovered it is a cascade of events, and that once the first step is taken a series of others quickly followed on.

They found that when white blood cells have a genetic mutation that is linked to leukemia, they are prone to inflammation. That inflammation then activates ADAR1, which in turn slows down a segment of microRNA called let-7 resulting in increased cell growth. The end result is that the white blood cells that began this cascade become leukemia stem cells and spread an aggressive and frequently treatment-resistant form of the blood cancer.

Having uncovered how ADAR1 works Jamieson and her team then tried to find a way to stop it. They discovered that by blocking the white blood cells susceptibility to inflammation, they could prevent the cascade from even starting. They also found that by using a compound called 8-Aza they could impede ADAR1’s ability to stimulate cell growth by around 40 percent.

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Catriona Jamieson – definitely not a zombie

Jamieson says the findings open up all sorts of possibilities:

“Based on this research, we believe that detecting ADAR1 activity will be important for predicting cancer progression. In addition, inhibiting this enzyme represents a unique therapeutic vulnerability in cancer stem cells with active inflammatory signaling that may respond to pharmacologic inhibitors of inflammation sensitivity or selective ADAR1 inhibitors that are currently being developed.”

This wasn’t a CIRM-funded study but we have supported other projects by Dr. Jamieson that have led to clinical trials.

 

 

 

 

New stem cell approach targeting deadly blood cancers

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Every four minutes someone in the US is diagnosed with a blood cancer. It might be lymphoma or leukemia, myeloma or myelodysplastic syndromes (MDS). While we have made great strides in treating some of these over the years, we still have a long way to go. Need proof? Well, every nine minutes someone in the US dies from a blood cancer.

Because of that need, the CIRM Board last week approved $3.5 million to help fund the search for a more effective, more efficient way to treat people suffering from blood cancer.

The Board funded a program by Angiocrine Biosciences, a San Diego-based company that is developing a new method for transplanting cord blood into patients.

Now cord blood transplants have been around for decades and they can be very effective. But they can also cause serious, even life-threatening complications. And they have limitations. For example some cord blood units are small and don’t have as many stem cells as the doctors would like. As a result, patients may need to spend longer in the hospital recovering from the procedure, putting them at increased risk of viral infections or pneumonia. Alternatively, doctors could use more than one cord blood unit for each transplant and while that seems to be an effective alternative, some studies suggest it can also carry an increased risk for serious complications such as Graft-versus-host disease (GVHD) where the newly transplanted cells attack the patient’s body.

To get around these issues, Angiocrine is developing a product called AB-110. This takes stem cells from cord blood, uses a specialized manufacturing facility to expand their numbers and then mixes them with genetically modified endothelial cells, the kind of cell that forms the lining of blood vessels.

It’s hoped that AB-110 will reduce the complications and increase the chances the transplanted cells will successfully engraft, meaning they start growing and creating new, healthy, blood cells.

In a news release CIRM’s President and CEO, C. Randal Mills, PhD, says this program fits in perfectly with our mission of accelerating stem cell treatments to patients with unmet medical needs:

“This project aims to do precisely that, speeding up the body’s ability to create new white blood cells and platelets – both essential qualities when treating deadly diseases like leukemia and lymphoma. Under CIRM 2.0, we are trying to create a pipeline of products that move out of the lab and into clinical trials in people, and we’re hopeful this program will demonstrate it’s potential and get approval from the Food and Drug Administration (FDA) to begin a clinical trial.”

Everyone at Angiocrine and CIRM will work as hard as we can to move this research toward a clinical trial as fast as we can. But in the meantime there are tens of thousands of critically ill people in desperate need of a life-saving transplant.

One way of helping those in need is for new parents to donate their child’s umbilical cord blood to the state’s umbilical cord blood collection program. This is a safe procedure that doesn’t harm the baby but could save someone’s life.

The cord blood program is housed at the UC Davis Institute for Regenerative Cures – a facility CIRM helped build and where we fund many great projects. This program is particularly important because it collects and stores cord blood units that reflect the state’s diverse communities, and that are available to all those in need of a transplant.

The bank also is a rich source of cord blood units for research, particularly for stem cell research, which will hopefully lead to even more effective therapies in the future.

Smoking out Leukemia Cells to Prevent Cancer Relapse

Ninety-five percent of all patients with chronic myeloid leukemia (CML), carry a Frankenstein-like gene, called BCR-ABL, created from an abnormal fusion of two genes normally found on two separate chromosomes. Like a water faucet without a shutoff valve, the resulting mutant protein is stuck in an “on” position and leads to uncontrolled cell division and eventually to CML as well as other blood cancers.

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An oversized bone marrow cell, typical of chronic myeloid leukemia. Credit:  Difu Wu

Gleevec, a revolutionary, targeted cancer drug that specifically blocks the BCR-ABL protein was approved by the FDA in 2001 and doubled 5-year survival rates for CML patients (31 to 59%) over that decade. Still, some patients who are responsive to the Gleevec class of drugs, become resistant to the treatment and suffer a relapse. Up until now, research studies pointed to an accumulation of additional DNA mutations as the driving force behind a rebound of the cancer cells.

But on Monday, a CIRM-funded UC San Diego team reported in PNAS that a reduction in just one protein, called MBNL3, in CML cancer cells activates a cascade of genes normally responsible for the unlimited self-renewing capacity of embryonic stem cells. Much like a researcher can reprogram a skin cell back into an embryonic like state via the induced pluripotent stem cell (iPSC) technique, this finding suggests that CML enhances its ability to spread by exploiting the same cellular reprogramming machinery.

CML is a slowly progressing cancer that initially begins with a chronic phase. At this stage, the cancerous cells, called blast cells, make up less than five percent of cells in the bone marrow. The phase usually lasts several years and is well controlled by drug treatment. A blast crisis phase follows when the blast cells make up 20 to 30% of the blood or bone marrow. At this stage, the patient’s condition deteriorates as symptoms like anemia and frequent infections worsen.

The UCSD team, led by Catriona Jamieson, director of Stem Cell Research at Moores Cancer Center, did a comparative analysis of CML patient samples and found that a reduction of MBNL3, a RNA binding protein, corresponded with CML progression from the chronic to blast phase. If you took intro biology in high school or college, you may recall that RNA acts as a messenger molecule critical to the translation of DNA’s genetic code into proteins. Some splicing and trimming of the RNA molecule occurs to prep it for this translation process. It turns out the decrease in MBNL3 in blast phase cells frees up stretches of RNA that leads to alternate splicing and, in turn, alternate forms of a given protein.

The study showed that in response to the decrease of MBNL3, an alternate form of the protein CD44, aptly named CD44 variant 3 (CD44v3), is increased in CML blast phase cells compared with chronic phase cells. Artificially over producing CD44v3 increased the activity of SOX2 and OCT4, two genes that are critical for maintaining the properties of embryonic stem cells. Genes involved with homing blood cells to the bone marrow were also upregulated.

Put together, these data suggest that this alternate RNA splicing not only helps CML blast phase cells preserve stem cell-like qualities, but it also helps sequester them in the bone marrow. Other studies have shown that the BCR-ABL protein inhibitor drugs are not effective in eradicating blast phase cells in the bone marrow, perhaps the reason behind relapse in some CML patients.

To try to smoke out these hiding blast phase cells in mouse CML studies, the team tested a combination treatment of a CD44 inhibitor along with the BCR-ABL inhibitor. While either treatment alone effectively removed the CML blast phase cells from the spleen and blood, only the combination significantly reduced survival of the cells in the bone marrow.

This tantalizing result has motivated the Jamieson team to pursue the clinical development of a CD44 blocking antibody with combination with the existing BCR-ABL inhibitors. As reported by Bradley Fikes in a San Diego Union Tribune story, the CD44 blocking antibody was not stable so more work is still needed to generate a new antibody.

But the goal remains the same as Jamieson mentions in a UCSD press release:

“If we target embryonic versions of proteins that are re-expressed by cancer, like CD44 variant 3, with specific antibodies together with tyrosine kinase [for example, BCR-ABL] inhibitors, we may be able to circumvent cancer relapse – a leading cause of cancer-related mortality.”

 

 

 

 

 

Holy Guacamole! Nutrient in Avocado Kills Cancer Stem Cells

Over four billion avocados were sold last year in the U.S. and for good reason – they’re so darn delicious and good for you too (wish you could say the same for doughnuts). Often called the world’s perfect food, avocados are high in fiber and packed with vitamins. Even the fat they contain is the healthy kind that’s associated with lower cholesterol levels and healthier hearts. As if the news couldn’t get any better, research published this week now suggests that a nutrient found in avocado can kill cancer stem cells – a cell type thought to be the source of a cancer’s unlimited growth and spread.

avocado, the world's perfect food

avocado, the world’s perfect food

The study, reported in Cancer Research by a Canadian research team at the University of Waterloo, focuses on a particularly deadly form of blood cancer called acute myeloid leukemia (AML). Often striking adults over 65, AML has a poor prognosis with only 10% survival after five years for this age group.

The cancer is caused by rapid, abnormal growth of white blood cells in the bone marrow that eventually crowds out normal blood cells leading to a deterioration of vital functions of the blood like carrying oxygen to the body. Chemotherapy or bone marrow transplants are standard treatments but unfortunately, even when successful, a majority of AML patients will relapse.

Though they make up a tiny portion of the leukemia, cancer stem cells are thought to be the main culprits behind AML relapse due to their stem cell-like ability for unlimited growth. The research team identified a nutrient in avocados called avocatin B with the ability to kill AML cancer stem cells. The killing mechanism of avocatin B was pinpointed to its disruption of the mitochondria, the cell’s energy “factory”, in leukemia cells, which led to cell death. As senior author Professor Paul Spagnuolo points out in a university press release, this cancer killing property of avocatin B promises to have limited side effects:

“We’ve performed many rounds of testing to determine how this new drug works at a molecular level and confirmed that it targets [cancer] stem cells selectively, leaving healthy cells unharmed.”

Now, before you rush out to the grocery store and stock up on nothing but avocados, keep in mind this is a preliminary study in petri dishes. Extensive follow up studies will be required before testing in humans can begin. Also, it’s not clear if eating avocado or an avocado extract would be a sufficient method of delivering avocatin B to keep cancer stem cells at bay. It’s more likely that avocatin B would be purified and provided as a food nutrient drug or a so-called nutraceutical:

“Extracts are less refined. The contents of an extract can vary from plant to plant and year to year, depending on lots of factors – on the soil, the location, the amount of sunlight, the rain,” explains Spagnuolo. “Evaluating a nutraceutical as a potential clinical drug requires in-depth evaluation at the molecular level. This approach provides a clearer understanding of how the nutraceutical works, and it means we can reproduce the effects more accurately and consistently. This is critical to safely translating our lab work into a reliable drug that could be used in oncology clinics.”

I look forward to following this story in the months and years to come with the hope that families devastated by an AML diagnosis will have more treatment options.