Monday, December 08, 2008

Cui's work on cancer with granulocytes

Granulocytes are a particular sort of white blood cell. Read the original New Scientist article or a related article in Science Daily. See a video of granulocytes attacking cancer cells. The video above is a talk by the primary investigator, Zheng Cui. I learned about this in stumbling across the fact that Chris Heward is seeking granulocyte donors.

Zheng Cui at Wake Forest University of Medicine in Winston-Salem, North Carolina, took blood samples from more than 100 people and mixed their granulocytes with cervical cancer cells. While granulocytes from one individual killed around 97 per cent of cancer cells within 24 hours, those from another healthy individual only killed around 2 per cent of cancer cells. Average cancer-killing ability appeared to be lower in adults over the age of 50 and even lower in people with cancer. It also fell when people were stressed, and at certain times of the year. "Nobody seems to have any cancer-killing ability during the winter months from November to April," says Cui.

Elsewhere, Cui wrote: "In 1999, we encountered a unique mouse that refused to succumb to repeated challenges with lethal cancer cells that uniformly killed all other laboratory mice, even at much lower doses. Further studies of this phenotype reveal that this unusual cancer resistance is inheritable and entirely mediated by the macrophages and neutrophils of the innate immunity. Transfer of leukocytes with this high level of cancer-killing activity (CKA) from these cancer-resistant mice cures the most aggressive advanced cancers in other mice without any side effect. Most surpisingly, a similar activity of killing cancer cells was discovered in the granulocytes and monocytes of some healthy people." When applied clinically, this is called LIFT, or "leukocyte infusion therapy".

Cui readily admits that he has not yet done much to explore the precise mechanisms involved. For the present, he is more interested in getting the treatment through clinical trials and into clinical practice. So he has gotten very little support from the medical community, and it's been difficult to secure funding for clinical trials.


PeterVermont said...

I have been excited about Dr. Cui's work for a while and hosted him at Dartmouth to present his work.

I find the non-existent cancer killing activity (CKA) during winter especially intriguing since I am also very interested in vitamin D. Among many other virtues, vitamin D is known to reduce risk for many cancers.

I liked his drive towards human therapy -- most other researchers would still be spending their time characterizing the mouse but Dr. Cui instead took made a lateral move to use the CKA assay on humans.

I am still interested to know what the mutation in the CR/SR mouse is -- it seems unlikely but I can't keep from wondering if it might be something related to activating the vitamin D receptor since we know it has a large role in innate immunity.

Will Ware said...

I also like that he prioritized human therapy first. I will often hear about some fascinating idea for attacking cancer or other disease, and then years later I see that it still hasn't gotten into clinical practice.

It's frustrating to be an engineer in a society that doesn't always seem to be pushing for the rapid development of effective treatments and cures. Where there are real questions of risk, lengthy studies are an understandable necessary evil. But the opposition to Cui's work looks to me to be a shameful cultural bias that may be costing patients' lives.

I certainly hope Cui gets a chance to sequence genetic material from his CR mice and compare it to non-CR mice. That would be really useful, and I'm surprised that other cancer researchers aren't beating down his door to get the differential sequence information.

I was unaware of the connection to vitamin D. I wonder if there is any relevant data for mice.