There is disclosed a composition in the form of a nanoparticle. The nanoparticle composition has a diameter from 5 to 500 nanometers. The nanoparticle composition has i) a central core portion including magnetic Fe3O4 nanoparticles adapted to act as a heat source when subjected to a magnetic field and a chemotherapeutic agent configured to treat cancer tissues, ii)—a shell portion including a shell member encapsulating said core portion, and iii)—antibodies configured to target cancer stem cells and adhered to surface of said shell member. The chemotherapeutic agent is a heat shock protein inhibitor and is releasable on activation of the heat source due to the magnetic field, and the shell member is made of silica or a silica based material. Surface of the nanoparticle is modified with the antibodies capable of binding with a cluster of differentiation molecules on the cell surface of the target cancer stem cells, whereby by way of combination of specificity of the nanoparticle composition due to the antibody, thermo-therapeutic effect of the Fe3O4 nanoparticles, and release of the heat shock protein inhibitor on site at the target cancer stem cells, inhibition of the target cancer stem cells is synergistically and additionally enhanced is increased.