A recent study has discovered a new drug which is an effective way to terminate cancer cells. This said drug is called an ATR inhibitor, scientists still do not entirely understand how they work, but many are working on ways to figure out how to add these into cancer-fighting therapies. Researchers state, a kinase, which is the ATR, can sense any harm to the DNA in cells. ATR signals are said to start “homologous recombination factors,” abbreviated to (HR.) HR factors play a key role when it comes to the DNA repair system, ATR inhibitors are able to block signaling, and can prevent DNA repair from the possibly damaged cells. Because the genomes of cancer cell are much more damaged, they are able to replicate more often. An associate in the Department of Molecular Biology named Marcus Smolka states, “If you really want to affect HR in cancer cells you need to inhibit it chronically for a long time.” He stated this as it was discovered that HR drops worked more effectively if the cells are treated for a longer timespan; in this case it was eight days and the HR levels decreased drastically.