The present invention relates to a pharmaceutical composition which includes nanoparticles. The nanoparticles include a glyceryl monooleate or monolinoleate (or other mono fatty acid ester) a chitosan and a cancer therapeutic agent, such as gemcitabine, taxanes, and hydrophobic cancer therapeutic agents). Also disclosed are methods for preparing such nanoparticles and pharmaceutical compositions, as well as methods for treating breast, pancreatic, colon, prostate, and other cancers by parenterally, intravenously, or otherwise administering such nanoparticles and pharmaceutical compositions.