Israeli researchers have identified a material that could help remedy lung cancer. In tests conducted by researchers at Hadassah University Hospital, Ein Kerem on cell samples and laboratory mice, the material shrank tumors by about 50 percent, and when it was used in conjunction with radiation therapy and chemotherapy, the pace of cancerous cell growth was reduced by about 90 percent.
The study was conducted by Dr. Ori Wald, a physician-researcher at Hadassah’s Cardiothoracic Surgery Department; with department head Prof. Oz Shapira; Dr. Uzi Izhar, director of the thoracic surgery unit; and Prof. Amnon Peled of the hospital’s gene therapy unit.
The researchers examined the impact of two components, a receptor called CXCR4 and a protein that cleaves to it called CXCL12, which has been identified in many studies as present in cancer patients.
In studies that they did on lung cancer tissue removed from patients, the researchers found that the cancerous cells contained both the receptor and the protein in concentrations that increased as the cancer became more advanced and aggressive. They later discovered that adding the protein CXCL12 to cancerous lung tumor cells made the growths more virulent.
The researchers then found that a material known as BKT140 succeeded in preventing the protein and receptor from connecting to each other, which led to the death of cancerous lung tumor cells and a reduction in the size of the growths.
The blocker was developed by Biokine Therapeutics of Rehovot for a totally different purpose – as a drug to be given to bone marrow donors to streamline and hasten the production of bone marrow cells before the donation.
Injecting the blocker into lab-grown lung tumor cells and later into mice significantly retarded the tumors’ growth and reduced their volume by about 50 percent.
“We injected the blocker into the mice, and it found its way to the site where the tumor was developing in the lung, where it helped reduce the volume of the tumor,” said Shapira.
In searching for a way to improve the efficiency of the blocker, they found that using it together with traditional cancer therapies reduced the tumors’ rates of growth by about 90 percent, in tests conducted so far only on lab samples.
In addition to radiation and chemotherapy, both of which have side effects, some cancers are being fought with new methods. These include focused biological treatments that use antibodies to block enzymes that encourage tumor growth; antibodies that damage the blood vessels that sustain the tumor; drugs that damage the casing of the tumor, thus preventing its growth; and treatments that boost the patient’s own immune system’s ability to fight the tumor.
“This blocker constitutes a new method for dealing with a tumor, by delaying the encounter between the receptor and the protein, although we don’t yet understand all the mechanisms at work,” said Wald.
The findings were presented earlier this month at the American Association for Thoracic Surgery conference in San Francisco, and the researchers are planning to submit requests to approve clinical trials on people.
Wald expects no problems with obtaining the approval, noting: “The material was already developed as a remedy and has already proven to have a high safety profile with few side effects.”
The researchers are working on another study aimed at identifying exactly how the blocker works to reduce the size of tumors.
Lung cancer is the second most common cancer in both men and women, and is also one of the deadliest cancers in the Western world, with survival rates of only 20 percent after five years.
According to a Health Ministry report issued in October 2010, lung cancer causes 21.5 percent of all men’s cancer deaths in Israel, and 9.9 percent of women’s deaths from cancer.