Scientists make small-cell lung cancer breakthrough

Scientists have discovered a way to predict which patients with small-cell lung cancer may be resistant to first-line chemotherapy.

This breakthrough made by Researchers for TGen Clinical Research Services at Scottsdale Healthcare (TCRS) is critical since patients with small-cell lung cancer (SCLC) often do not get a second chance at therapies to combat this aggressive type of cancer.

"For patients with small cell lung cancer, there are really only about two chemotherapy options. We need to be more precise with our treatments and identify who is going to be resistant up front in order to design better clinical trials that will identify effective therapies for these at-risk patients," said Dr. Glen J. Weiss, director of Thoracic Oncology at TCRS.

The study led by Dr Weiss proposed to look at how to best identify those SCLC patients who would be chemoresistant.

By profiling tumors, he and a team of TGen researchers identified at least three tumor microRNAs that appear to predict small cell lung cancer patients who will prove resistant to first-line chemotherapy.

MicroRNAs are small molecules that regulate gene expression in the process of making proteins as well as directing the structure and function of cells. This regulation usually prevents cancer and other diseases.

Weiss and colleagues evaluated 34 patients at with varying stages of SCLC. The median age of the patients was 69.1 years, and half were men. All 34 received systemic chemotherapy.

There were two complete responses and 13 partial responses. Two patients had stable disease and four had progressive disease.

Three microRNAs biomarkers were identified as being closely linked with chemoresistance: miR-92a-2*, miR-147, and miR-574-5p.

Although 47% of the patients presented with hypertension and 32% presented with emphysema or chronic obstructive pulmonary disease, neither of these co-morbidities were linked with chemoresistance.

These findings should help clinicians design better drug trials.

The study has been presented in San Diego at a joint conference of the American Association for Cancer Research (AACR) and the International Association for the Study of Lung Cancer (IASLC).