Researchers from Australia have shed light on a better way of identifying which patients will be better respondents to the powerful ovarian cancer drug called the PARP inhibitors and which will not, answering a riddle in the treatment of ovarian cancer about why these drugs work better in case of some patients and not so much on others. This adds to a crucial checklist that is often referred to when deciding the course of action for ovarian cancer patients; finding targeted treatments for the condition is necessary to improve patient survival rates, which have not improved notably over the past three decades.
The researchers state that PARP inhibitors work only in ovarian cancer patients when the DNA repair process of the cancer was not functioning, owing to the fact that the BRCA1 genes are silenced, as normally as in normal cases. However, even in the cases that the scientific world thought that the PARP inhibitor therapy should work, it did not often work. Researchers have now found subtle changes in some cancers with silenced BRCA1 gene. This made researchers realize that all the patients from this group will also not respond in the same way of PARPi.
The study has demonstrated that the only factor leading to a faulty DNA repair process in cancer cells is not incomplete methylation. Researchers analyzed these nuances in previous assumptions using patient derived xenografts (PDX) and quality data sets. The use of PDX models turned out to be highly effective owing to the fact that PDX models very closely mimic the complexity of cancerous cells at crucial stages during the progression of cancer. The study has been published in the Nature Communications journal.