Nanoscale Particles Deliver Crispr Cancer Treatments

Crispr-Cas9 illustration (LBL.gov)

19 Nov. 2020. Researchers in Israel developed techniques to deliver gene editing therapies with lipid nanoscale particles that in lab mice killed cancer cells and increased survival. A team from Tel Aviv University describes its technology and lab results in yesterday’s issue of the journal Science Advances.

The Tel Aviv team from the precision nanomedicine lab of Dan Peer, also the university’s vice-president for R&D, is seeking effective mechanisms for delivering gene-editing therapeutics for cancer. Up to now, say the researchers, gene-editing techniques such as Crispr are hampered by inefficient editing and in some cases toxicity to patients. Crispr, short for clustered regularly interspaced short palindromic repeats, is a genome-editing process based on bacterial defense mechanisms that use RNA to identify, monitor, and edit precise locations in DNA.

“The Crispr genome editing technology, capable of identifying and altering any genetic segment,” says Peer in a university statement, “has revolutionized our ability to disrupt, repair, or even replace genes in a personalized manner. Despite its extensive use in research, clinical implementation is still in its infancy because an effective delivery system is needed to safely and accurately deliver the Crispr to its target cells.”

Peer’s lab studies drug delivery strategies including delivery of nucleic acids, such as RNA or DNA, using lipid, or natural oil, nanoscale particles. Among their techniques is engineered lipids ionized, or with electrical charges changed, for more efficient delivery of nucleic acids, including RNA payloads designed for genome-editing therapies.

In this case, the lipid nanoparticles are transporting RNA to deliver Crispr gene-editing treatments against two of the more aggressive solid-tumor cancers — glioblastoma tumors in the brain and ovarian cancer — each with a poor prognosis and low survival rates. The study tests the feasibility of engineered lipid nanoparticles to deliver Crispr payloads with Cas9 editing enzymes, guided by RNA molecules, to treat lab mice induced with glioblastoma or ovarian tumors.

For glioblastoma, Crispr payloads aimed for the polo like kinase 1, or PLK1 gene, associated with various types of cancer. Results show the lipid nanoparticles enabled Cas9 enzymes to edit out that gene in up to 70 percent of the cases. These edits led to tumor cell death in the affected mice, reduced tumor growth by about half, and increased survival of about 30 percent.

To treat ovarian cancer, the lipid nanoparticles carried Cas9 to edit out the epidermal growth factor receptor or EGFR gene, where mutations of that gene are also associated with cancer. Results show about 80 percent of the deliveries succeeded in editing out the target gene, with reduced tumor growth and increased survival of about 80 percent.

Peer points out that “this is not chemotherapy. There are no side effects, and a cancer cell treated in this way will never become active again. The molecular scissors of Cas9 cut the cancer cell’s DNA, thereby neutralizing it and permanently preventing replication.”

The researchers believe lipid nanoparticles carrying Crispr therapies can be applied to other types of cancer, as well as genetic diseases and chronic viral disorders such as HIV/AIDS. Tel Aviv University received or filed for patents on the technology, and Peer says the university’s technology transfer office is already negotiating with international foundations and corporations to bring the discoveries to market.

More from Science & Enterprise:

• Crispr Therapy Shown to Help Blood Disorder Patients
• Crispr Heart Therapy Demonstrated in Monkeys
• Biotechs Partner on Crispr for Stem Cell Transplants
• Biotechs Apply Crispr Gene-Editing for Hemophilia
• Patient Receives First Crispr Genetic Eye Treatment

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