Variable Molecular Weight Polymer Nanoparticles for Detection and Hyperthermia-Induced Chemotherapy of Colorectal Cancer.

Oxaliplatin plays a significant role as a chemotherapeutic agent for the treatment of colorectal cancer (CRC); however, oxaliplatin-resistant phenotypes make further treatment challenging. Here, we have demonstrated that rapid (60 s) hyperthermia (42 °C), generated by the near-infrared stimulation of variable molecular weight nanoparticles (VMWNPs), increases the effectiveness of oxaliplatin in the oxaliplatin-resistant CRC cells. VMWNP-induced hyperthermia resulted in a higher cell death in comparison to cells exposed to chemotherapy at 42 °C for 2 h. Fluorescence from VMWNPs was observed inside cells, which allows for the detection of CRC. The work further demonstrates that the intracellular thermal dose can be determined using cell luminescence and correlated with the cell viability and response to VMWNP-induced chemotherapy. Mild heating makes oxaliplatin-resistant cancer cells responsive to chemotherapy, and the VMWNPs-induced hyperthermia can induce cell death in a few minutes, compared to classical bulk heating. The results presented here lay the foundation for photothermal polymer nanoparticles to be used for cell ablation and augmenting chemotherapy in drug-resistant colorectal cancer cells.