Introduction to Plasmonic Photothermal-Assisted Multimodal Cancer Therapeutics

As per World Health Organization (WHO)’s cancer statistics, cancer is regarded as the deadliest disease, accounting for about 10 million deaths worldwide in 2020. Current clinical practices include surgery, chemotherapy, and radiation therapy, but these possess significant side effects and the treatment efficacy is limited due to the lack of specificity, targetability and resistance toward chemotherapeutic drugs. So, there is a need for other cancer therapeutics with high specificity, which would destroy the cancerous cells with minimal side effects. In this regard, recently, nanoparticles and near-infrared (NIR) radiation-based therapeutic modalities like plasmonic photothermal therapy (PPTT), photochemotherapy and photodynamic therapy (PDT) are attracting considerable attention because of their minimal invasiveness, improved cancer site selectivity, and better treatment effectiveness. But due to the limitations associated with these individual therapies, like poor thermal damage zones (in PPTT), tumor hypoxia issues (in PDT), or inadequate accumulation of drug (in chemotherapy), a single therapy is not sufficient to attain complete eradication of cancer. To address this, nowadays, multimodal cancer therapy is an emerging selective cancer treatment strategy, which implies combining multiple therapeutic modalities into a single nanoplatform so that the resultant therapeutic outcome would be better than single therapy. This nanoparticle-based multimodal cancer therapy thus has the potential as a selective and efficient cancer treatment as an advancement toward cancer therapeutics. So, this chapter starts with a brief introduction about various types of cancer and its leading causes, followed by global statistics on burden of cancer disease. The available conventional cancer treatment modalities are then discussed, citing each therapy’s basics, key features and limitations. Next, to address the shortcomings of the available cancer therapies, multifunctional nanocomposite-based PPTT-assisted multimodal cancer therapy is introduced as an alternative to conventional cancer therapies with better therapeutic effects. Various PPTT-assisted multimodal therapy approaches, viz. PPTT-assisted PDT, PPTT-assisted chemotherapy, PPTT-assisted immunotherapy, etc. (achieved by loading different therapeutic agents on multifunctional nanocomposite) are discussed along with the mechanism by which this multimodal therapeutic approach leads to better therapeutic outcome that are otherwise not achieved with individual therapies. Lastly, various steps involved in PPTT-assisted multimodal cancer therapy are listed, and finally, this chapter concludes by illustrating a brief outline of this book.