In 1982, Dr. Richard Edelson MED ’70 and Dr. Carole Berger, then researchers at Columbia University, developed photopheresis — a revolutionary and surprisingly successful treatment for Cutaneous T-Cell Lymphoma, or CTCL, a cancer affecting the skin. More than two decades later, Edelson and Berger, now at the Yale Cancer Center, have taken their research a step further.
The two scientists are currently developing transimmunization, a therapy that could potentially be an enormous advance in the treatment of all types of cancer. Berger said this new research topic is the result of an investigation of the poorly understood mechanism of photopheresis. Although transimmunization is still being developed, it has already shown promise in combating a wide range of cancers. The researchers are currently trying to gain approval from Yale’s Human Investigation Committee, or HIC, to use transimmunization for lung cancer and other malignancies.
Clinical studies have already started for CTCL patients, with good results, Berger said.
“We’ve treated about 13 patients, [and] we’ve found that about 30 to 40 percent of the patients show improvements in their skin disease,” Berger said.
Transimmunization and photopheresis treatment are both considered to be fairly safe compared to standard radiation and chemotherapy procedures. Neither transimmunization nor photopheresis has been associated with toxic side effects.
By investigating the process of photopheresis — in which malignant white blood cells are collected from a patient’s tumor and exposed to ultraviolet light before being returned to the patient’s body — Edelson, Berger and a team of Yale researchers discovered unintended positive results. The combination of UV light and the chemical 8-methoxypsoralen, which is injected in patients before harvesting their cells, resulted in the proliferation of dendritic cells. These cells improved the patients’ immune responses.
In contrast to photopheresis, transimmunization exposes white blood cells to UV light for an entire night instead of a brief period of time. The researchers said they believe this process gives the dendritic cells more time to mature, thereby increasing the body’s immune response to them.
Berger said transimmunization is, in essence, an extension of the photopheresis procedure.
“Dr. Edelson thought if we incubated the cells over night, perhaps we might be able to induce a greater immune response,” she said.
Berger said preliminary tests have shown transimmunization to be particularly effective for reducing malignant circulation in patients with certain types of leukemia.
The Yale researchers said they are especially excited about the potential of using transimmunization to combat solid tumors like lung cancer. Berger said traditional radiation or chemotherapy would first target the tumor, and then transimmunization would be used in an attempt to rid the body of the remaining malignancy.
To use transimmunization on non-CTCL cancers, the researchers must gain approval from the HIC, which is responsible for reviewing, approving and monitoring all procedures involving human subjects. But HIC Director Robert Lange said his committee had not yet seen anything related to non-CTCL transimmunization procedures.
“We have approved Cutaneous T-Cell Lymphoma trials,” Lange said. “As far as I know, I have not received [any requests for other transimmunization trials].”
Lange said once the researchers file suitable protocols and consent agreements with the HIC, the procedure will be approved or denied within a week.
“Everyone on the committee has the right to object [and veto a proposal], and everybody is required to read every protocol that comes before the committee,” Lange said.
The Middletown Press reported in a Sept. 27 article that Edelson had used transimmunization to cure his father-in-law of lung cancer.
However, Berger said the man’s recovery may have been caused by other factors.
“[Edelson] had a patient with lung cancer that he treated with radiation, photopheresis,” Berger said. “[It was an] anecdotal occurrence, [but] there might be something of interest there.”