Tailoring nanomaterials for cancer therapy: A comprehensive insight into theranostics and limitations

Nanotheranostics has emerged as a promising approach in cancer therapy. It enables the diagnosis of cancer cells and targeted drug delivery on a single platform. Due to their small size, unique surface architecture, and electrochemical properties, nanoparticles conjugated with anti-cancer drugs, such as doxorubicin, paclitaxel, cisplatin, and methotrexate, have been found to selectively target various cancer cell types while having minimal impact on healthy cells. Metal nanoparticles such as gold, silver, and iron oxide nanoparticles have demonstrated excellent drug-delivery potential. Other nanoformulations, including carbon nanotubes, graphene oxide, quantum dots, liposomes, and nanoemulsions, have been investigated by researchers worldwide and have yielded promising results for targeting cancer cells. Nanoparticles are widely being investigated for nanotheranostics due to their enhanced imaging contrast. Superparamagnetic iron oxide nanoparticles have been used as MRI contrast agents to detect cancers in the spleen, lymph nodes, and liver. Similarly, gold, quantum dots, and carbon nanotubes exhibit excellent optical properties to detect tumors and their biomarkers. Nanoparticles, such as carbon nanotubes, silver nanoparticles, and quantum dots, have been observed to selectively increase temperature within cancer cells, thereby inducing apoptosis, ferroptosis, and cuproptosis. In addition, some nanoformulations have been found to modulate the immune system by altering cytokine levels and triggering dendritic cell maturation and cytotoxic T-cell activation to kill cancer cells. Therefore, the present review aims to provide an extensive discussion of recent advances, existing limitations, and research gaps in cancer nanotheranostics.