Methods for treatment of a multi-drug resistant (MDR) tumor in a subject are disclosed. The methods comprise administering to the subject in need of treatment a therapeutically effective amount of an anti-mycoplasma agent and/or an agent blocking the interaction between membrane protein P37 of mycoplasma and Annexin A2 of host cells of the subject, prior to, at the same time with, or after chemotherapy. Relevant pharmaceutical compositions, kits, uses are also disclosed.
