Potential Therapy Aims for Cancer Bull's-Eye

Small cell lung cancer may have new targeted drug therapy

(RxWiki News) Research has found that cell enzymes are key to controlling the spread of lung cancer. Now scientists have pinpointed an enzyme that responds to drug treatment, killing cancer cells.

British researchers have identified an enzyme that is essential to the survival of small cell lung cancer (SCLC) tumors.

They have also shown that targeted drug therapy can wipe out specific SCLC cells with a specific type of gene.

"Ask a doctor about the latest targeted cancer drug therapies."

Small cell lung cancer (SCLC) spreads more quickly than other types of lung cancer, and is one of the most deadly forms of the disease.

Patrick Eyers, PhD, senior lecturer at the University of Sheffield's Institute for Cancer Studies in Britain, led a lab study, in collaboration with investigators in Cologne, Germany, finding that SCLC cells grown from human tumors rely on an enzyme called the Aurora kinase.

His team went on to demonstrate that drugs called Aurora kinase inhibitors could effectively kill SCLC cells when these cells have high levels of the Myc cancer gene.

Many cancers are driven by the Myc gene. Scientists at the Dana-Farber Cancer Institute in Boston call the Myc gene a master regulator that activates cell growth in tumors.

Dr. Eyers’ report says these kinase-inhibiting drugs might be most beneficial for SCLC patients with a “Myc gene amplification,” a condition found in up to 7 percent of patients diagnosed with SCLC.

Several drug companies have already developed or are developing aurora kinase inhibitors, including SNS-314 from Sunesis Pharmaceuticals, CYC116 from Cyclacel and MLN8054 from Millennium.

Dr. Eyers suggests that these inhibitors should be further tested in clinical trials as targeted drug treatment against SCLC.

The survival rate for SCLC patients remains very low. Two-thirds of people are diagnosed in the late stages of the disease and, according to investigators, the 5-year survival rate for these patients is less than 5 percent.

"Current chemotherapy for SCLC kills cancerous cells and non-cancerous cells indiscriminately and results in severe side effects,” said Dr. Eyers. "However, revolutionary clinical trials have recently validated 'molecularly targeted' kinase inhibitors for treating cancers such as melanoma, leukemia and non-small cell lung cancer.”

Dr. Ross Camidge, who is clinical director of the Thoracic Oncology Program at the University of Colorado Denver and has a focus in Developmental Therapeutics, added, “This preclinical study adds to the emerging literature about potential targets in small cell lung cancer. As with all preclinical research, we will not know its true significance until it is explored in the clinical arena. Certainly, there has not been a breakthrough in SCLC for decades and one is desperately needed.”

The study was published in October in the journal Proceeding of the National Academy of Sciences of the United States of America (PNAS).

Review Date: 
October 13, 2012