Chinese Scientists To Carry Out First Human Gene Editing Trial For Lung Cancer

Researchers in China will be testing the revolutionary CRISPR-Cas9 gene editing technique in a lung cancer trial.

AsianScientist (Aug. 2, 2016) – Oncologists in China are about to be the first in the world to conduct a gene editing trial in humans based on the CRISPR–Cas9 technique.

A team led by Dr. Lu You at Sichuan University’s West China Hospital in Chengdu received approval to carry out the trial from the hospital’s review board on July 6, in a process that took just half a year.

CRISPR, which stands for clustered regularly interspaced short palindromic repeats, are repeats of base sequences in DNA. Scientists at Osaka University in Japan found CRISPR sequences in bacteria in 1987. Interestingly, CRISPR sequences are invariably followed by a group of genes encoding DNA-cutting enzymes, which are termed CRISPR-associated genes, or Cas for short.

The potential for these sequences to be used in gene editing came as somewhat of a revelation. Researchers at Danish food manufacturer Danisco had discovered that exposure to bacteria-infecting viruses caused Streptococcus thermophilus—a bacterium used in the food industry to convert lactose into lactic acid—to insert some of the viral DNA into the spacers within CRISPR sequences. This effectively ‘vaccinated’ the bacteria against the virus, as the CRISPR sequences would guide the corresponding Cas enzymes to ‘snip out’ the viral DNA.

This month, the clinical research team will be injecting lung cancer patients with immune cells that have been modified using CRISPR-Cas9. In an interview with Nature, Lu detailed how the study will enroll patients who have metastatic non-small cell lung cancer and for whom conventional therapies have so far failed.

“Treatment options are very limited,” Lu shared with Nature. “This technique is of great promise in bringing benefits to patients, especially the cancer patients whom we treat every day.”

According to the research team, they will first extract immune cells called T cells from the patients. The treatment will use CRISPR-Cas9 technology to knock out a gene encoding for the programmed cell death protein 1, or PD-1, a protein that normally prevents T cells from attacking healthy cells. The researchers will then multiply the T cells in the lab and re-introduce them into the patient’s bloodstream in hope that the T cells target the cancer cells.

The upcoming Phase I trial will examine the effects of three different dosage regimens on ten patients, according to the research team. The researchers will also monitor markers in the blood of the patients, which would indicate whether the treatment is working.

In general, the primary goal for a Phase I clinical trial is to show that people can safely use a new treatment or drug. There remains the danger that gene editing will take place at an off-site location. As such, the research team said they will be collaborating with biotech company Chengdu MedGenCell to ensure that the correct genes are knocked out in the immune cells.


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Coming from a design background, Filzah brings a fresh perspective to science communications. She is particularly interested in healthcare and technology.

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