Notes of a Reform Watcher -Gene Therapy As A Cure for Leukemia

August 15, 2011 - This morning I awake with Lewis Thomas on my mind. If you’ve forgotten or ever knew, Lewis Thomas (1913-1993) was a pathologist. He was famous for writing Lives of a Cell: Notes of a Biology Watcher, a 1974 collection of 29 essays first published in the New England Journal of Medicine.

His working hypothesis was that cures of disease would evolve from basic research on the cell, not from “half-way technologies,” such as renal dialysis. He said workings of the cell were complicated, and victories over disease would not come quickly.

I thought of Lewis Thomas because of news just released that gene therapy had definitely cured one patient with chronic lymphoid leukemia.

Here is how Ron Winslow reported the news in an August 11, 2011 Wall Street Journal piece “Gene Therapy Offers Hope in Leukemia Patients.”

A new strategy for genetically bolstering the immune system proved surprisingly powerful against an advanced form of leukemia in a small study that could have broader implications for fighting cancer.

The treatment, in which cells from the three participating patients were manipulated using gene therapy, eradicated blood cancer tumors in less than a month and led to sustained remissions of up to a year.

The Associated Press and CBS news picked up on the story and gave this spin under the headline, “ ‘Amazing’ Gene Therapy Destroys Leukemia in Three Patients.”

Scientists are reporting the first clear success with gene therapy to treat leukemia, turning the patients' own blood cells into assassins that hunt down and wipe out their cancer.

They've only done it in three patients so far, but the results were striking: Two appear cancer-free up to a year after treatment, and the third had a partial response. Scientists are already preparing to try the approach for other kinds of cancer.

From there the story spread to other news outlets, and you would have thought the cure for all leukemias and other cancers was at hand.

I was excited too until I read August 10 the complicated New England Journal article under the formidable title “Chimeric Antigen Receptor – Modified T Cells in Chronic Lymphoid Leukemia.”

After describing their work, the authors concluded,

The delayed onset of the tumor lysis syndrome and cytokine secretion, combined with vigorous in vivo chimeric antigen receptor T-cell expansion and prominent antileukemia activity, points to substantial and sustained effector functions of the CART19 cells. Our early research highlights the potency of this therapy and provides support for the detailed study of autologous T cells genetically modified to target CD19 (and other targets) through transduction of a chimeric antigen receptor linked to potent signaling domains. Unlike antibody-mediated therapy, chimeric antigen receptor–modified T cells have the potential to replicate in vivo, and long-term persistence could lead to sustained tumor control. Two other patients with advanced CLL have also received CART19 infusions according to this protocol, and all three have had tumor responses.These findings warrant continued study of CD19-redirected T cells for B-cell neoplasms.

No promise of a cure there, only that their results warranted "continued study," and no mention of the application of their research to other malignancies.
As Lewis Thomas noted, the life of the cell is complicated, and one cannot always make far-reaching conclusions from limited data. Still, basic cellular research offers hope, and hope is all that many leukemia patients have to hang their hats and their future on.