SLC7A11 and neoplasm: Animals were treated with vehicle (black) or CB-839 (blue) and received normal (solid line) or doxycycline (dashed line) feed starting from day 13 (arrow indicating treatment start, n = 6 tumors) (h) Subcutaneous tumor volumes of KPK tumors expressing a doxycycline inducible shRNA targeted against Slc7a11 (shSlc7a11).