Exploring the Role of Nanotherapeutics for Diagnosis and Treatment of Solid Tumor

Background Tumors are increasingly heterogeneous throughout the process of their growth, producing a mixed-cell community with a range of molecular features and susceptibility to therapies. Nanotechnology has shown tremendous potential in diagnosing and treating solid tumors.Objective Most cancer-related deaths are attributed to the lack of early detection and effective treatment. Its early diagnosis helps overall survival and health-related quality of life in patients identified with cancer. Nanosystems are favorable for endocytic intracellular retention, high drug loading, enhanced therapeutic efficacy, greater drug-circulation time, superior dose scheduling for patient compliance, and site-specific targeting. Integrating nanosystems into biomedical applications will also reintroduce medicines that are no longer used in clinical practice because of certain drawbacks and help the identification of new active medicines with their sub-optimal kinetic profiles. This review provides insights about the targeted cancer treatment based on active targeting (folate receptor-alpha, heat shock protein, receptor 2 for epidermal human growth factor, and CD44 receptor) and various nano device-based systems.Methodology The highly relevant articles were retrieved using various search engines, including Web of Sciences, Science Direct, Scihub, PubMed, Scopus, PubChem, Google Scholar, and others. The keywords and phrases used for the search are "liposomes," "quantum dots," "nanoparticles," "nanocrystals," "photodynamic therapy," "passive targeting," "active targeting," "nanomaterials," "nanotechnology," "cancer," "nanotheranostics" and several others. In this review, we briefly introduced the concept of the contribution of nanotheranostics to cancer therapy with their recent findings. We also discuss the role of biosensor-based nanosystems in cancer.Conclusion This review addresses nanotechnology's exciting role in identifying, imaging, and managing solid tumors and their immense potential.