Not All Patients Suited for First-Line Therapy.

• Position: BREAST CANCER TREATMENT

Two challenges in treating patients with estrogen-positive breast cancer (ER+) have been an inability to predict who will respond to standard therapies and adverse events leading to therapy discontinuation. A study at The University of Texas MD Anderson Cancer Center, Houston, has revealed new information about how the biomarkers retinoblastoma protein (Rb) and cytoplasmic cyclin E could indicate which patients will respond best to current first-line therapies.

The study also discovered that combining the current therapy with autophagy inhibitors will result in using one-fifth of the dosage of the standard treatment, which significantly could reduce side effects associated with this therapy.

Standard treatment, consisting of palbociclib, often has adverse side effects and not all ER+ patients respond to it Palbociclib inhibits proteins called CDK4 and CDK6 (CDK4/6) and tumor cells escape this inhibition by activating autophagy, a process allowing cancer cells to thrive even when starved of nutrients. By combining palbociclib with autophagy inhibitors in cells that express normal Rb and nuclear cyclin E, the dose of...