There are provided, inter alia, compositions and methods for treatment of chemoresistant cancer (breast cancer). The methods include administering to a subject in need a therapeutically effective amount of a chemotherapeutic agent and a ROR- 1 antagonist. Further provided are pharmaceutical compositions including chemotherapeutic agent, ROR- 1 antagonist and a pharmaceutically acceptable excipient. In embodiments, the chemotherapeutic agent is paclitaxel and the ROR- 1 antagonist is cirmtuzumab.