Lung cancer is the leading cause of cancer–related death in the United States, and each year claims more lives than breast, colon, ovarian and prostate cancers combined.
In 2010, there will be more than 220,000 new cases, and 150,000 deaths from lung cancer. The most common form of lung cancer is non-small cell lung cancer (NSCLC), and more than half of NSCLC patients have advanced disease by the time they visit their doctor. This is one reason why lung cancer is so deadly. At the advanced stages of disease, surgery and chemotherapy are the only real treatment options, and unfortunately many lung cancers are resistant to chemotherapy. Chemotherapy drugs are designed to kill tumor cells by damaging their DNA, because DNA is essential for cells to divide. Therapy-resistant cancers get around this problem by repairing the damage, which allows them to replicate the DNA and continue dividing. Researchers at the Torrey Pines Institute are working on ways to block lung cancer cells from repairing their DNA.
Dr. Ruth Gjerset is developing inhibitors of DNA repair pathways to overcome therapy resistance by tumors in the lung. Her lab is investigating how the inhibitors block essential pathways and make tumor cells more sensitive to conventional therapies without affecting normal tissue. This should lower the effective dose of therapy, reducing toxicity. The inhibitors belong to a class of “therapy-sensitizing” drugs, and if effective, they may also reverse therapy resistance in advanced cancers.