Taking a new approach to fighting a deadly brain cancer

Christine Brown DSC_3794

Christine Brown, Ph.D., City of Hope researcher

CIRM’s 2017 Annual Report will be going live online very soon. In anticipation of that we are highlighting some of the key elements from the report here on the Stem Cellar.

One of the most exciting new approaches in targeting deadly cancers is chimeric antigen receptor (CAR) T-cell therapy, using the patient’s own immune system cells that have been re-engineered to help them fight back against the tumor.

Today we are profiling City of Hope’s Christine Brown, Ph.D., who is using CAR-T cells in a CIRM-funded Phase 1 clinical trial for an aggressive brain cancer called malignant glioma.

“Brain tumors are the hardest to treat solid tumors. This is a project that CIRM has supported from an early, pre-clinical stage. What was exciting was we finished our first milestone in record time and were able to translate that research out of the lab and into the clinic. That really allowed us to accelerate treatment to glioblastoma patients.

I think there are glimmers of hope that immune based therapies and CAR-T based therapies will revolutionize therapy for patients with brain tumors. We’ve seen evidence that these cells can travel to the central nervous system and eliminate tumors in the brain.

We now have evidence that this approach produces a powerful, therapeutic response in one group of patients. We are looking at why other patients don’t respond as well and the CIRM funding enables us to ask the questions that will, we hope, provide the answers.

Because our clinical trial is a being carried out at the CIRM-supported City of Hope Alpha Stem Cell Clinic this is a great example of how CIRM supports all the different ways of advancing therapy from early stage research through translation and into clinical trials in the CIRM Alpha Clinic network.

There are lots of ways the tumor tries to evade the immune system and we are looking at different approaches to combine this therapy with different approaches to see which combination will be best.

It’s a challenging problem and it’s not going to be solved with one approach. If it were easy we’d have solved it by now. That’s why I love science, it’s one big puzzle about how do we understand this and how do we make this work.

I don’t think we would be where we are at without CIRM’s support, it really gave the funding to bring this to the next level.”

Dr. Brown’s work is also creating interest among investors. She recently partnered with Mustang Bio in a $94.5 million agreement to help advance this therapy.

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Stem Cell RoundUp: CIRM Clinical Trial Updates & Mapping Human Brain

It was a very CIRMy news week on both the clinical trial and discovery research fronts. Here are some the highlights:

Stanford cancer-fighting spinout to Genentech: ‘Don’t eat me’San Francisco Business Times

Ron Leuty, of the San Francisco Business Times, reported this week on not one, but two news releases from CIRM grantee Forty Seven, Inc. The company, which originated from discoveries made in the Stanford University lab of Irv Weissman, partnered with Genentech and Merck KGaA to launch clinical trials testing their drug, Hu5F9-G4, in combination with cancer immunotherapies. The drug is a protein antibody that blocks a “don’t eat me” signal that cancer stem cells hijack into order to evade destruction by a cancer patient’s immune system.

Genentech will sponsor two clinical trials using its FDA-approved cancer drug, atezolizumab (TECENTRIQ®), in combination with Forty Seven, Inc’s product in patients with acute myeloid leukemia (AML) and bladder cancer. CIRM has invested $5 million in another Phase 1 trial testing Hu5F9-G4 in AML patients. Merck KGaA will test a combination treatment of its drug avelumab, or Bavencio, with Forty-Seven’s Hu5F9-G4 in ovarian cancer patients.

In total, CIRM has awarded Forty Seven $40.5 million in funding to support the development of their Hu5F9-G4 therapy product.


Novel regenerative drug for osteoarthritis entering clinical trialsThe Scripps Research Institute

The California Institute for Biomedical Research (Calibr), a nonprofit affiliate of The Scripps Research Institute, announced on Tuesday that its CIRM-funded trial for the treatment of osteoarthritis will start treating patients in March. The trial is testing a drug called KA34 which prompts adult stem cells in joints to specialize into cartilage-producing cells. It’s hoped that therapy will regenerate the cartilage that’s lost in OA, a degenerative joint disease that causes the cartilage that cushions joints to break down, leading to debilitating pain, stiffness and swelling. This news is particularly gratifying for CIRM because we helped fund the early, preclinical stage research that led to the US Food and Drug Administration’s go-ahead for this current trial which is supported by a $8.4 million investment from CIRM.


And finally, for our Cool Stem Cell Image of the Week….

Genetic ‘switches’ behind human brain evolutionScience Daily

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This artsy scientific imagery was produced by UCLA researcher Luis del la Torre-Ubieta, the first author of a CIRM-funded studied published this week in the journal, Cell. The image shows slices of the mouse (bottom middle), macaque monkey (center middle), and human (top middle) brain to scale.

The dramatic differences in brain size highlights what sets us humans apart from those animals: our very large cerebral cortex, a region of the brain responsible for thinking and complex communication. Torre-Ubieta and colleagues in Dr. Daniel Geschwind’s laboratory for the first time mapped out the genetic on/off switches that regulate the growth of our brains. Their results reveal, among other things, that psychiatric disorders like schizophrenia, depression and Attention-Deficit/Hyperactivity Disorder (ADHD) have their origins in gene activity occurring in the very earliest stages of brain development in the fetus. The swirling strings running diagonally across the brain slices in the image depict DNA structures, called chromatin, that play a direct role in the genetic on/off switches.

Recap of the 2018 Alliance for Regenerative Medicine Cell and Gene Therapy State of the Industry

What happened in the Cell and Gene Therapy sector in 2017, and what should we be looking out for in 2018? Over 500 executives, investors, scientists and patient advocates gathered together yesterday to find out at the Alliance for Regenerative Medicine (ARM) State of the Industry Briefing in San Francisco, California.

ARM Chairman, Robert Preti, and ARM CEO, Janet Lynch Lambert, kicked off the session by discussing how 2017 marked an inflection point for the sector. They underscored the approval of three cell/gene therapies (see slide below) by the U.S. Food and Drug Administration (FDA), a “bright and robust” future pipeline that should yield over 40 approved therapies in the next five years, and an improving regulatory environment that’s accelerating approvals of regenerative medicine therapies. This year alone, the FDA has granted 12 Regenerative Medicine Advanced Therapy (RMAT) designations through the 21st Century Cures Act (see slide below for companies/products that received RMAT in 2017).

In 2017, a total of four cell/gene therapies were approved and the US FDA awarded 12 RMAT designations. This slide is from the 2018 ARM Cell and Gene Therapy State of the Industry Briefing presentation.

Next up was a snapshot of the clinical landscape highlighting a total of 946 ongoing clinical trials at the end of 2017, and their breakdown by disease (see chart below). Oncology (cancer) is the clear winner comprising over 50% of the trials while Cardiovascular (heart) took second with 8.6% and diseases of the central nervous system (brain and spinal cord) took third with 6.5%.

Lambert also gave a brief overview of finances in 2017 and listed some impressive numbers. $7.5 Billion in capital was raised in 2017 compared to $4.2 Billion in 2016. She also mentioned major acquisitions, mergers, partnerships and public financings that paved the way for this year’s successes in cell and gene therapy.

Lambert concluded that while there was significant progress with product approvals, growing public awareness of successes in the sector, regulatory advances and financial maturity, there is a need for further commercial support and a focus on policy making, industrialization and manufacturing.

The Industry Update was followed by two panel sessions.

The first panel focused on cell-based cancer immunotherapies and featured company leaders from Juno Therapeutics, Mustang Bio, Adaptimmune, Novartis, and Fate Therapeutics.

In the cancer field, companies are aggressively pursuing the development of cell-based immunotherapies including Chimeric Antigen Receptor T (CAR-T) cells, modified T-cells and Natural Killer (NK) cells, to name a few. These therapies all involve engineering or modifying human immune cells to identify and target cancer cells that resist first-line cancer treatments like radiation or chemotherapy.

The panelists spoke of a future that involved the development of combination therapies that partner cell-based immunotherapies with other drugs and treatments to better target specific types of cancer. They also spent a significant portion of the panel discussing the issues of manufacturing and reimbursement. On manufacturing, the panel argued that a centralized cell manufacturing approach will be needed to deliver safe products to patients. On reimbursement, they addressed the difficulty of finding a balance between pricing life-saving therapies and navigating reimbursements from insurance companies.

The second panel focused on the state of gene therapy and the outlook for 2018. This panel featured company and academic leaders from CRISPR Therapeutics, Sangamo Therapeutics, BioMarin Pharmaceutical, Adverum Biotechnologies, and the Gladstone Institutes.

ARM Gene Therapy Panel: Martha Rook (MilliporeSigma), Deepak Srivastava (Gladstone Institutes), Amber Salzman (Adverum Biotechnologies), Bill Lundberg (CRISPR Therapeutics), Geoff Nichol (BioMarin Pharmaceutical), Sandy Macrae (Sangamo Therapeutics)

The panel spoke about the difference between gene editing (fixing an existing gene within a cell) and gene therapy (adding a new gene into a cell) technologies and how the delivery of these therapies into tissues and cells is the biggest challenge in the area right now.

Sandy Macrae, President and CEO of Sangamo Therapeutics, made an interesting point when he said that for gene therapy to be successful, companies need to plan two to three years in advance for a phase III trial (the final stage before a product is approved) because manufacturing gene therapies takes a long time. He said the key for success is about having medicines that are ready to launch, not just reporting good results.

Overall, ARM’s State of the Industry provided an exciting overview of the progress made in the Cell and Gene Therapy Sector in 2017 and shared outlooks for 2018 and beyond.

You can access the Live Webcast of ARM’s State of the Industry Briefing including both panel sessions on the ARM website. Be sure to check out our blog featuring our 2018 Stem Cell Conference Guide for more ARM events and other relevant stem cell research meetings in the coming year.

Stem Cell Roundup: Gene therapy for diabetes, alcohol is bad for your stem cells and hairy skin

The start of a new year is the perfect opportunity to turn a new leaf. I myself have embraced 2018 with open arms and decided to join my fellow millennials who live and die by the acronym YOLO.

How am I doing this? Well, so far, I got a new haircut, I started doing squats at the gym, and I’m changing up how we blog on the Stem Cellar!

On Fridays, we always share the stem cell stories that “caught our eye” that week. Usually we pick three stories and write short blogs about each of them. Over time, these mini-blogs have slowly grown in size to the point where sometimes we (and I’m sure our readers) wonder why we’re trying to pass off three blogs as one.

Our time-honored tradition of telling the week’s most exciting stem cell stories on Friday will endure, but we’re going to change up our style and give you a more succinct, and comprehensive roundup of stem cell news that you be on your radar.

To prove that I’m not all talk, I’m starting off our new Roundup today. Actually, you’re reading it right now. But don’t worry, the next one we do won’t have this rambling intro 😉.

So here you go, this week’s eye-catching stem cell stories in brief:


Gene therapy helps mice with type 1 diabetesEurekAlert!

A study in Cell Stem Cell found that gene therapy can be used to restore normal blood sugar levels in mice with type 1 diabetes. The scientists used a virus to deliver two genes, PDX1 and MAFA, into non-insulin producing pancreatic cells. The expression of these two proteins, reprogrammed the cells into insulin-producing beta cells that stabilized the blood sugar levels of the mice for 4 months. While the curative effects of the gene therapy weren’t permanent, the scientists noted that the reprogrammed beta cells didn’t trigger an immune response, indicating that the cells acted like normal beta cells. The researchers will next test this treatment in primates and if it works and is safe, they will move onto clinical trials in diabetic patients.


Alcohol increases cancer risk in mice by damaging stem cell DNA – GenBio

*Fair warning for beer or wine lovers: you might not want to read story.

Cambridge scientists published a study in Nature that suggests a byproduct of alcohol called acetaldehyde is toxic to stem cells. They gave watered-down alcohol to mice lacking an essential enzyme that breaks down alcohol in the liver. They found that the DNA in the blood-forming stem cells of the mice lacking this enzyme were four times more damaged than the DNA of normal mice. Excessive DNA damage creates instability in the genetic material of cells, which, over time, can lead to cancer. While many things can cause cancer, individuals who aren’t able to process alcohol effectively should take this study into consideration.


Stem cell therapy success for sclerodoma patientsThe Niche

For those of you unfamiliar with sclerodoma, it’s an autoimmune disease that can affect the skin, blood vessels, muscle tissue and organs in the body. Rather than recreate the wheel, here’s an overview of this study by UC Davis Professor Paul Knoepfler in his blog called The Niche:

Paul Knoepfler

A new NIH-funded study reported in the New England Journal of Medicine (NEJM) gives some hope for the use of a combination of a specific type of myeloablation [a form of chemotherapy] and a transplant of hematopoietic stem cells. This approach yields improved long-term outcomes for patients with a severe form of scleroderma called systemic sclerosis. While survival rates for systemic sclerosis have improved it remains a very challenging condition with a significant mortality rate.”


Phase III stem cell trial for osteoarthritis starts in JapanEurekAlert!

Scientists in Japan have developed a stem cell-based therapy they hope will help patients with osteoarthritis – a degenerative joint disease that causes the breakdown of cartilage. The therapy consists of donor mesenchymal stem cells from a commercial stem cell bank. The team is now testing this therapy in a Phase III clinical trial to assess the therapy’s safety and effectiveness. As a side note, CIRM recently funded a clinical trial for osteoarthritis run by a company called CALIBR. You can read more about it here.


Cool Stem Cell Photo of the Week

I’ll leave you with this rad photo of hairy skin made from mouse pluripotent stem cells. You can read about the study that produced these hairy skin organoids here.

In this artwork, hair follicles grow radially out of spherical skin organoids, which contain concentric epidermal and dermal layers (central structure). Skin organoids self-assemble and spontaneously generate many of the progenitor cells observed during normal development, including cells expressing the protein GATA3 in the hair follicles and epidermis (red). Credit: Jiyoon Lee and Karl R. Koehler

How Tom Howing turned to stem cells to battle back against a deadly cancer

As we enter the new year, CIRM’s 2017 Annual Report will be posted in less than two weeks!  Here’s one of the people we are profiling in the report, a patient who took part in a CIRM-funded clinical trial.

Tom Howing

In March of 2015, Tom Howing was diagnosed with stage 4 cancer. Over the next 18 months, he underwent two rounds of surgery and chemotherapy. Each time the treatments held the cancer at bay for a while. But each time the cancer returned. Tom was running out of options and hope when he heard about a CIRM-funded clinical trial using a new approach.

The clinical trial uses a therapy that blocks a protein called CD47 that is found on the surface of cancer cells, including cancer stem cells which can evade traditional therapies. CD47 acts as a ‘don’t eat me’ signal that tells immune cells not to kill off the cancer cells. When this ‘don’t eat me’ signal is blocked by the antibody, the patient’s immune system is able to identify, target and kill the cancer stem cells.

“When I was diagnosed with cancer I knew I had battle ahead of me. After the cancer came back again they recommended I try this CD47 clinical trial. I said absolutely, let’s give it a spin.

“I guess one is always a bit concerned whenever you put the adjective “experimental” in front of anything. But I’ve always been a very optimistic and positive person and have great trust and faith in my caregivers.

“Whenever you are dealing with a Phase 1 clinical trial (the earliest stage where the goal is first to make sure it is safe), there are lots of unknowns.  Scans and blood tests came back showing that the cancer appears to be held in check. My energy level is fantastic. The treatment that I had is so much less aggressive than chemo, my quality of life is just outstanding.”

Tom says he feels fortunate to be part of the clinical trial because it is helping advance research, and could ultimately help many others like him.

“The most important thing I would say is, I want people to know there is always hope and to stay positive.”

He says he feels grateful to the people of California who created CIRM and the funding behind this project: “I say a very heartfelt thank you, that this was a good investment and a good use of public funds.”

He also wants the researchers, who spent many years developing this approach, to know that they are making a difference.

“To all those people who are putting in all the hours at the bench and microscope, it’s important for them to know that they are making a huge impact on the lives of real people and they should celebrate it and revel in it and take great pride in it.”

Harnessing the body’s immune system to tackle cancer

Often on the Stem Cellar we write about work that is in a clinical trial. But getting research to that stage takes years and years of dedicated work. Over the next few months, we are profiling some of the scientists we fund who are doing Discovery (early stage) and Translational (pre-clinical) research, to highlight the importance of this work in developing the treatments that could ultimately save lives. 

This second profile in the series is by Ross Okamura, Ph.D., a science officer in CIRM’s Discovery & Translation Program.

Your immune system is your body’s main protection against disease; harnessing this powerful defense system to target a given disorder is known as immunotherapy.  There are different types of immunotherapies that have been developed over the years. These include vaccines to help generate antibodies against viruses, drugs to direct immune cell function and most recently, the engineering of immune cells to fight cancer.

Understanding How Immunotherapies Work

One of the more recent immunotherapy approaches to fight cancer that has seen rapid development is equipping a subset of immune cells (T cells) with a chimeric antigen receptor (CAR). In brief, CAR T ceIls are first removed from the patient and then engineered to recognize a specific feature of the targeted cancer cells.  This direct targeting of T cells to the cancer allows for an effective anti-cancer therapy made from your own immune system.

Simplified explanation of how CAR T cell therapies fight cancer. (Memorial Sloan Kettering)

For the first time this fall, two therapeutics employing CAR T cells targeting different types of blood cancers were approved for use by the US Food and Drug Administration (FDA) based on remarkable results found during the clinical trials. Specifically, Kymriah (developed by Novartis) was approved for treatment of acute lymphoblastic leukemia and Yescarta (developed by Kite Pharma) was approved for treatment of non-Hodgkin lymphoma.

There are drawbacks to the CAR T approach, however. Revving up the immune system to attack tumors can cause dangerous side effects. When CAR T cells enter the body, they trigger the release of proteins called cytokines, which join in the attack on the tumors. But this can also create what’s referred to as a cytokine storm or cytokine release syndrome (CRS), which can lead to a range of responses, from a mild fever to multi-organ failure and death. Balancing treatments to resolve CRS after it’s detected while still maintaining the treatment’s cancer-killing abilities is a significant challenge that remains to be overcome.  A second issue is that cancer cells can evade the immune system by no longer producing the target that the CAR-T therapy was designed to recognize. When this happens, the patient subsequently experiences a cancer relapse that is no longer treatable by the same cell therapy.

Natural Killer (NK) T cells represent another type of anti-cancer immunotherapy that is also being tested in clinical trials. NK cells are part of the innate immune system responsible for defending your body against both infection and tumor formation.  NK cells target stressed cells by releasing cell-penetrating proteins that poke holes in the cells leading to induced cell death.  As an immunotherapy, NK cells have the potential to avoid both the issues of CRS and cancer cell immune evasion as they release a more limited array of cytokines and do not rely on a specific single target to recognize tumors.  NK cells instead selectively target tumor cells due to the presence of stress-induced proteins on the cancer cells. In addition, the cancer cells lack other proteins that would normally send out a “I’m a healthy cell you can ignore me” message to NK cells. Without that message, NK cells target and kill those cancer cells.

Developing new immunotherapies against cancer

Dan Kaufman, UCSD

Dr. Dan Kaufman of the University of California at San Diego is a physician-scientist whose research group developed a method to produce functional NK cells from human pluripotent stem cells (PSC).  In order to overcome a major hurdle in the use of NK cells as an anti-cancer therapeutic, Dr. Kaufman is exploring using stem cells as a limitless source to produce a scalable, standardized, off-the-shelf product that could treat thousands of patients.  CIRM is currently funding Dr. Kaufman’s work under both a Discovery Quest award and a just recently funded Translational research award in order to try to advance this candidate approach.

In the CIRM Translational award, Dr. Kaufman is looking to cure acute myelogenous leukemia (AML) which in the US has a 5-year survival rate of 27% (National Cancer Institute, 2017) and is estimated to kill over 10,000 individuals this year (American Cancer Society, 2017).  He has previously shown that his stem cell-derived NK cells can kill human cancer cells in a dish and in mouse models, and his goals are to perform preliminary safety studies and to develop a process to scale his production of NK cells to support a clinical trial in people.  Since NK cells don’t require the patient and the donor to be a genetic match to be effective, a bank of PSC-derived NK cells derived from a single donor could potentially treat thousands of patients.

Looking forward, CIRM is also providing Discovery funding to Dr. Kaufman to explore ways to improve his existing approach against leukemia as well as expand the potential of his stem cell-derived NK cell therapeutic by engineering his cells to directly target solid tumors like ovarian cancer.

The field of pluripotent stem cell-based immunotherapies is full of game-changing potential and important innovations like Dr. Kaufman’s are still in the early stages.  CIRM recognizes the importance of supporting early stage research and is currently investing $27.9 million to fund 8 active Discovery and Translation awards in the cancer immunotherapy area.

Scientists find switch that targets immunotherapies to solid tumors

Cancer immunotherapies harness the power of the patient’s own immune system to fight cancer. One type of immunotherapy, called adoptive T cell therapy, uses immune cells called CD8+ Killer T cells to target and destroy tumors. These T cells are made in the spleen and lymph nodes and they can migrate to different locations in the body through a part of our circulatory system known as the lymphatic system.

CD8+ T cells can also leave the circulation and travel into the body’s tissues to fight infection and cancer. Scientists from the Scripps Research Institute and UC San Diego are interested in learning how these killer T cells do just that in hopes of developing better immunotherapies that can specifically target solid tumors.

In a study published last week in the journal Nature, the teams discovered that a gene called Runx3 acts as a switch that programs CD8+ T cells to set up shop within tissues outside of the circulatory system, giving them access to solid tumors.

“Runx3 works on chromosomes inside killer T cells to program genes in a way that enables the T cells to accumulate in a solid tumor,” said Matthew Pipkin, co-senior author and Associate Professor at The Scripps Research Institute.

Study authors Adam Getzler, Dapeng Wang and Matthew Pipkin of The Scripps Research Institute collaborated with scientists at the University of California, San Diego.

They discovered Runx3 by comparing what genes were expressed in CD8+ T cells found in the lymphatic system to CD8+ T cells that were found in tissues outside of the circulation. They then screened thousands of potential factors for their ability to influence CD8+ T cells to infiltrate solid tumors.

“We found a distinct pattern,” Pipkin said. “The screens showed that Runx3 is one at the top of a list of regulators essential for T cells to reside in non-lymphoid tissues.”

The team then set out to prove that Runx3 was a key factor in getting CD8+ T cells to localize at the site of solid tumors. To do this, they took T cells that either overexpressed Runx3 or did not express Runx3 in these cells. The T cells were then transplanted into mice with melanoma through a process known as adoptive cell transfer. Overexpression of Runx3 in T cells not only reduced tumor size but also extended lifespan in the mice. On the other hand, removing Runx3 expression had a negative impact on their survival rate.

This research, which was supported in part by CIRM funding, offers a new strategy for developing better cancer immunotherapies for solid tumors.

Pipkin concluded in a Scripps Research Institutes News Release,

“Knowing that modulating Runx3 activity in T cells influences their ability to reside in solid tumors opens new opportunities for improving cancer immunotherapy. We could probably use Runx3 to reprogram adoptively transferred cells to help drive them to amass in solid tumors.”

CIRM-Funded Research Makes Multiple Headlines this Week

When it rains it pours.

This week, multiple CIRM-funded studies appeared in the news, highlighting the exciting progress our Agency is making towards funding innovative stem cell research and promoting the development of promising stem cell therapies for patients.

Below are highlights.


Fate Therapeutics Partners with UC San Diego to Develop Cancer Immunotherapy

Last week, Dr. Dan Kaufman and his team at UC San Diego, received a $5.15 million therapeutic translational research award from CIRM to advance the clinical development of a stem cell-derived immunotherapy for acute myelogenous leukemia (AML), a rare form of blood cancer.

Today, it was announced that the UCSD team is entering into a research collaboration with a San Diego biopharmaceutical company Fate Therapeutics to develop a related immunotherapy for blood cancers. The therapy consists of immune cells called chimeric antigen receptor-targeted natural killer (CAR NK) cells that can target tumor cells and stop their growth. Fate Therapeutics has developed an induced pluripotent stem cell (iPSC) platform to develop and optimize CAR NK cell therapies targeting various cancers.

According to an article by GenBio, this new partnership is already bearing fruit.

“In preclinical studies using an ovarian cancer xenograft model, Dr. Kaufman and Fate Therapeutics had shown that a single dose of CAR-targeted NK cells derived from iPSCs engineered with the CAR construct significantly inhibited tumor growth and increased survival compared to NK cells containing a CAR construct commonly used for T-cell immunotherapy.”

 


City of Hope Brain Cancer Trial Featured as a Key Trial to Watch in 2018

Xconomy posted a series this week forecasting Key Clinical Data to look out for next year. Today’s part two of the series mentioned a recent CIRM-funded trial for glioblastoma, an aggressive, deadly brain cancer.

Christine Brown and her team at the City of Hope are developing a CAR-T cell therapy that programs a patient’s own immune cells to specifically target and kill cancer cells, including cancer stem cells, in the brain. You can read more about this therapy and the Phase 1 trial on our website.

Alex Lash, Xconomy’s National Biotech Editor, argued that good results for this trial would be a “huge step forward for CAR-T”.

Alex Lash

“While CAR-T has proven its mettle in certain blood cancers, one of the biggest medical questions in biotech is whether the killer cells can also eat up solid tumors, which make up the majority of cancer cases. Glioblastoma—an aggressive and usually incurable brain cancer—is a doozy of a solid tumor.”


ViaCyte Receives Innovative New Product Award for Type 1 Diabetes

Last week, San Diego-based ViaCyte was awarded the “Most Innovative New Product Award” by CONNECT, a start-up accelerator focused on innovation, for its PEC-Direct product candidate. The product is a cell-based therapy that’s currently being tested in a CIRM-funded clinical trial for patients with high-risk type 1 diabetes.

In a company news release published today, ViaCyte’s CEO Paul Laikind commented on what the award signifies,

Paul Laikind

“This award acknowledges how ViaCyte has continually broken new ground in stem cell research, medical device engineering, and cell therapy scaling and manufacturing. With breakthrough technology, clinical stage product candidates, an extensive intellectual property estate, and a strong and dedicated team, ViaCyte has all the pieces to advance a transformative new life-saving approach that could help hundreds of thousands of people with high-risk type 1 diabetes around the world.”

Hey, what’s the big idea? CIRM Board is putting up more than $16.4 million to find out

Higgins

David Higgins, CIRM Board member and Patient Advocate for Parkinson’s disease; Photo courtesy San Diego Union Tribune

When you have a life-changing, life-threatening disease, medical research never moves as quickly as you want to find a new treatment. Sometimes, as in the case of Parkinson’s disease, it doesn’t seem to move at all.

At our Board meeting last week David Higgins, our Board member and Patient Advocate for Parkinson’s disease, made that point as he championed one project that is taking a new approach to finding treatments for the condition. As he said in a news release:

“I’m a fourth generation Parkinson’s patient and I’m taking the same medicines that my grandmother took. They work but not for everyone and not for long. People with Parkinson’s need new treatment options and we need them now. That’s why this project is worth supporting. It has the potential to identify some promising candidates that might one day lead to new treatments.”

The project is from Zenobia Therapeutics. They were awarded $150,000 as part of our Discovery Inception program, which targets great new ideas that could have a big impact on the field of stem cell research but need some funding to help test those ideas and see if they work.

Zenobia’s idea is to generate induced pluripotent stem cells (iPSCs) that have been turned into dopaminergic neurons – the kind of brain cell that is dysfunctional in Parkinson’s disease. These iPSCs will then be used to screen hundreds of different compounds to see if any hold potential as a therapy for Parkinson’s disease. Being able to test compounds against real human brain cells, as opposed to animal models, could increase the odds of finding something effective.

Discovering a new way

The Zenobia project was one of 14 programs approved for the Discovery Inception award. You can see the others on our news release. They cover a broad array of ideas targeting a wide range of diseases from generating human airway stem cells for new approaches to respiratory disease treatments, to developing a novel drug that targets cancer stem cells.

Dr. Maria Millan, CIRM’s President and CEO, said the Stem Cell Agency supports this kind of work because we never know where the next great idea is going to come from:

“This research is critically important in advancing our knowledge of stem cells and are the foundation for future therapeutic candidates and treatments. Exploring and testing new ideas increases the chances of finding treatments for patients with unmet medical needs. Without CIRM’s support many of these projects might never get off the ground. That’s why our ability to fund research, particularly at the earliest stage, is so important to the field as a whole.”

The CIRM Board also agreed to invest $13.4 million in three projects at the Translation stage. These are programs that have shown promise in early stage research and need funding to do the work to advance to the next level of development.

  • $5.56 million to Anthony Oro at Stanford to test a stem cell therapy to help people with a form of Epidermolysis bullosa, a painful, blistering skin disease that leaves patients with wounds that won’t heal.
  • $5.15 million to Dan Kaufman at UC San Diego to produce natural killer (NK) cells from embryonic stem cells and see if they can help people with acute myelogenous leukemia (AML) who are not responding to treatment.
  • $2.7 million to Catriona Jamieson at UC San Diego to test a novel therapeutic approach targeting cancer stem cells in AML. These cells are believed to be the cause of the high relapse rate in AML and other cancers.

At CIRM we are trying to create a pipeline of projects, ones that hold out the promise of one day being able to help patients in need. That’s why we fund research from the earliest Discovery level, through Translation and ultimately, we hope into clinical trials.

The writer Victor Hugo once said:

“There is one thing stronger than all the armies in the world, and that is an idea whose time has come.”

We are in the business of finding those ideas whose time has come, and then doing all we can to help them get there.

 

 

 

Second “Don’t Eat Me” Signal Identified in Cancer Cells, Points to New Immunotherapies

When the immune system comes up as a topic in everyday conversation, it’s usually related to fighting off a cold or flu. While our immune cells certainly do detect and neutralize invading bacteria and viruses, they also play a critical role in killing abnormal, cancerous cells from within our bodies.

“Don’t Eat Me” Signal 101
A white blood cell called a macrophage (macro = “big”; phage = “eater”) is part of the so-called innate immune system and acts as a first line of defense by patrolling our organs and gobbling up infected as well as cancerous cells (see macrophages in action in the cool video below).

Unfortunately, cancer cells possess the ability to cloak themselves and escape a macrophage’s engulfing grasp. Nearly all cancer cells carry a protein called CD47 on their surface. When CD47 binds to a protein called SIRPalpha on the surface of macrophages, a “don’t eat me” signal is triggered and the macrophage ignores the cancer cell.

Stanford researcher Irv Weissman and his team discovered this “don’t eat me” signal several years ago and showed that adding an antibody protein that binds tightly to CD47 interferes with the CD47/SIRPalpha signal. As a result, the anti-CD47 antibody deactivates the cancer cell’s “don’t eat me” signal and restores the macrophage’s ability to detect and kill the cancer cells.

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CD47 protein on surface of cancer cells triggers “don’t eat me signal” which can be blocked with anti-CD47 antibody. Image: Acrobiosystems

Because CD47 is found on the surface of most cancer cells, this anti-CD47 antibody represents an exciting new strategy for targeting cancer stem cells – the cells thought to maintain cancer growth and cause tumor relapse – in a wide variety of cancers. In fact, CIRM has provided funding for three clinical trials, one sponsored by Stanford University and two by Forty-Seven Inc. (a company that was spun out of Stanford), that are testing anti-CD47 therapy for the treatment of the blood cancer acute myeloid leukemia (AML), as well as colon cancer and other solid tumors.

“Reaching Clinical Trials” does not equal “The Research is Done”
Although these clinical trials are underway, the Weissman team continues to seek new insights related to blocking the CD47 “don’t eat me” signal. They observed that although anti-CD47 led to increased macrophage-induced killing of most cancer cell samples tested, some were resistant to anti-CD47 and remained cloaked from macrophages. And even the cancer cells that did respond to the antibody varied widely in the amount of increased killing by macrophages.

These results suggested that alternate processes may exist that allow some cancers to evade macrophages even when the CD47 “don’t eat me” signal is blocked. In a report published this week in Nature Immunology, the researchers report the identification of a second, independent “don’t eat me” signal, which may lead to more precise methods to disarm a cancer’s evasiveness.

To track down this alternate “don’t eat me” signal, they looked for, but didn’t find, correlations between specific types of cancer cells and the cancer’s resistance to anti-CD47 treatment.  So instead they analyzed surface proteins found on the various cancer cell samples and found that cancer cells that had high levels of MHC (Major Histocompatibility Complex) class I proteins were more likely to be resistant to anti-CD47 antibodies.

A Second “Don’t Eat Me” Signal
MHC class I proteins help another arm of the immune system, the adaptive immune response, detect what’s going inside a cell. They are found on nearly all cells and display, at the cell surface, bits of proteins sampled from inside the cell. If cells of the adaptive immune response, such as T or B cells, recognize one of those protein bits as abnormal or foreign, efficient killing mechanisms are kicked into high gear to destroy those cells.

But in the case of cancers cells, the MHC class I protein are harnessed as a “don’t eat me” signal by binding to a protein called LILRB1 on macrophages. When either the MHC class I proteins or LILRB1 were blocked, the “don’t eat me” signal was lifted and restored the macrophages’ ability to kill the cancer cells both in petri dish samples as well as in mice that carried human cancers.

Graduate student and co-lead author Amira Barkal described in a press release the impact of blocking both “don’t eat me” signals at the same time:

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Amira Barkal

“Simultaneously blocking both these pathways in mice resulted in the infiltration of the tumor with many types of immune cells and significantly promoted tumor clearance, resulting in smaller tumors overall. We are excited about the possibility of a double- or perhaps even triple-pronged therapy in humans in which we combine multiple blockades to cancer growth.”

The Big Picture for Cancer Immunotherapies
Because MHC protein class I proteins play an important role in stimulating immune cells called T cells to kill cancer cells as part of the adaptive immune response, the level of MHC protein on an individual patient’s cancer cells could serve as an indicator, or “biomarker”, for what type of cancer therapy to pursue.  The big picture implications of this idea are captured in the press release:

“Understanding the balance between adaptive and innate immunity is important in cancer immunotherapy. For example, it’s not uncommon for human cancer cells to reduce the levels of MHC class 1 on their surfaces to escape destruction by T cells. People with these types of tumors may be poor candidates for cancer immunotherapies meant to stimulate T cell activity against the cancer. But these cells may then be particularly vulnerable to anti-CD47 treatment, the researchers believe. Conversely, cancer cells with robust MHC class 1 on their surfaces may be less susceptible to anti-CD47.”