According to a study, a lysophosphatidic acid receptor 1 (LPAR1) inhibitor, known as Debio-0719, suppresses the development of metastases in mice by inducing cancer cell dormancy. The study is published in the August 21 issue of the Journal of the National Cancer Institute.
Metastasis is a main contributor to mortality in cancer patients. Patients with "triple negative" breast cancer (tumor cells that are hormone receptor negative and express normal levels of the HER2 oncogene) are known to be at high risk for metastatic progression.
In addition, breast and prostate cancers are known for having variable but possibly long periods of dormancy, where the disease is silent. Factors inducing or breaking a dormant state are poorly understood, but extending dormancy is considered a therapeutic goal.
The authors point out that LPA1 inhibition had no effect on the growth of the primary tumors in either model system. As such, it would not normally be considered further for drug development. Their data suggest that alternative drug development approaches may identify compounds with novel activities, such as metastatic dormancy.
The authors point out that their study did not determine the duration of tumor dormancy, and that Debio-0719 and other LPA1 inhibitors should be tested in additional model systems. However, they conclude: "With such inhibitors in hand, the interaction of dormancy pathways and standard of care therapeutics, radiation therapy, patient stress, and other important factors can be determined to develop a deeper picture of potential preventative and therapeutic scenarios."