Newly developed biosensor can target leukemic stem cells

Dr. Michael Milyavsky (left) and his research student Muhammad Yassin (right). Image courtesy of Tel Aviv University.

Every three minutes, one person in the United States is diagnosed with a blood cancer, which amounts to over 175,000 people every year. Every nine minutes, one person in the United States dies from a blood cancer, which is over 58,000 people every year. These eye opening statistics from the Leukemia & Lymphoma Society demonstrate why almost one in ten cancer deaths in 2018 were blood cancer related.

For those unfamiliar with the term, a blood cancer is any type of cancer that begins in blood forming tissue, such as those found in the bone marrow. One example of a blood cancer is leukemia, which results in the production of abnormal blood cells. Chemotherapy and radiation are used to wipe out these cells, but the blood cancer can sometimes return, something known as a relapse.

What enables the return of a blood cancer such as leukemia ? The answer lies in the properties of cancer stem cells, which have the ability to multiply and proliferate and can resist the effects of certain types of chemotherapy and radiation. Researchers at Tel Aviv University are looking to decrease the rate of relapse in blood cancer by targeting a specific type of cancer stem cell known as a leukemic stem cell, which are often found to be the most malignant.

Dr. Michael Milyavsky and his team at Tel Aviv University have developed a biosensor that is able to isolate, label, and target specific genes found in luekemic stem cells. Their findings were published on January 31, 2019 in Leukemia.

In a press release Dr. Milyavsky said:

“The major reason for the dismal survival rate in blood cancers is the inherent resistance of leukemic stem cells to therapy, but only a minor fraction of leukemic cells have high regenerative potential, and it is this regeneration that results in disease relapse. A lack of tools to specifically isolate leukemic stem cells has precluded the comprehensive study and specific targeting of these stem cells until now.”

In addition to isolating and labeling leukemic stem cells, Dr. Milyavsky and his team were able to demonstrate that the leukemic stem cells labeled by their biosensor were sensitive to an inexpensive cancer drug, highlighting the potential this technology has in creating more patient-specific treatment options.

In the article, Dr. Milyavsky said:

” Using this sensor, we can perform personalized medicine oriented to drug screens by barcoding a patient’s own leukemia cells to find the best combination of drugs that will be able to target both leukemia in bulk as well as leukemia stem cells inside it.”

The researchers are now investigating genes that are active in leukemic stem cells in the hope finding other druggable targets.

CIRM has funded two clinical trials that also use a more targeted approach for cancer treatment. One of these trials uses an antibody to treat chronic lymphocytic leukemia (CLL) and the other trial uses a different antibody to treat acute myeloid leukemia (AML).

Scientists say they’re one step closer to being able to build a new you, using your own stem cells.

Organ transplant

One of the biggest obstacles to transplanting organs from one person to another is that the immune system of the person getting the new life-saving organ often tries to reject it. The immune cells see the new material as “foreign” and attacks it, sometimes destroying it.

Right now, the only way to prevent that is by using powerful immunosuppressive drugs to keep the patient’s immune system at bay and protect the new organ. It’s effective, but it also comes with some long-term health consequences.

But now researchers at Tel Aviv University in Israel say they may have found a way around that, using the patient’s own stem cells.

The team says it was able to take fatty tissue from patients and, using the iPSC procedure, turn them into other kinds of cells to help repair different kinds of tissue.

In a story in the “Times of Israel”, Prof Tal Dvir, the lead researcher, said this new approach could theoretically be used to engineer any tissue type in the body.

“We were able to create a personalized hydrogel from the materials of the biopsy, to differentiate fatty tissue cells into different cell types and to engineer cardiac, spinal cord, cortical and other tissue implants to treat different diseases. Since both the cells and the material used derive from the patient, the implant does not provoke an immune response, ensuring proper regeneration of the defected organ.”

Dvir says the research, published in the journal Advanced Materials, has only been tested in animals so far but has shown great promise, helping regenerate damaged tissues in mice and rats. Their next goal is to see if they can replicate this in people.

“Theoretically we can work in every disease or disorder that cells are involved in, where tissue is dying. We can create the tissue to fix that injury by a simple injection of materials and cells at the injury site,”

While this has long been a goal of many stem cell researchers around the world, problems translating what looks good in animals into what works in people has invariably slowed down the progress of even the most promising approach. At least so far.