Precision drugs and DNA repair effective for cancer treatment
The advancements in immunotherapies boast some 10-20% of patients who are responsive to treatment, though many cancers still evade detection by the immune system.
But, recent studies have suggested that treatment with PARP inhibitors in precision drugs cause cancer cells to stimulate immune responses against the tumour.
When cancer cells with defective repair systems are treated with PARP inhibitors that block their remaining system of repair, they can only accumulate DNA mutations until they die.These include ovarian and breast cancers. The accumulation triggers the release of immune cells towards the tumour.
Professor Chris Lord and Dr. Sophie Postal-Vinay of the Institute of Cancer Research, London, and the Institut Gustave Roussy, France led the study on PARP inhibitors, funded by Breast Cancer Now and Cancer Research UK.
The researchers found that patients with deficient DNA repair had significantly more immune cells within their lung tumours.The researchers then studied non-small cell lung cancers and triple-negative breast cancers with mutations such as ERCC1 or BRCA for similar immune responses. About 30-50% of patients are deficient in the ERCC1 DNA repair system, so the stimulated responses by PARP inhibitors could provide more effective ways of treatment.
Lord has said that the findings substantially change the understanding of how PARP inhibitors function in a double-pronged attack like targeted immunotherapy.
Dr. Postel-Vinay has said the use of PARP inhibitors in immunotherapies willbe evaluated in clinical trials of lung, prostate and bladder cancers later this year.
Dr. Kotryna Temcinaite, Research Communications Manager at Breast Cancer Now, is eager to see how PARP inhibitors may work in clinical trials for breast cancer patients.
