Surface receptor-mediated targeted drug delivery systems for enhanced cancer treatment: A state-of-the-art review.

Enhanced cancer treatment remains as one of the focused areas for researchers around the world. Hence, the progress in this direction will be a challenge and an opportunity in, inter-disciplinary field to mitigate the suffering of millions in the upcoming decades. As we see, cancer death rate has also progressively increased despite the current impressive treatment regimens but also due to the non-availability of vaccines and the re-occurring of cancer in substantially recovered patients. Currently, numerous treatment strategies like surgical removal of solid tumors followed by radiation with a combination of immunotherapy/chemotherapy by the researchers and clinicians are routinely being followed. However, recurrence and distant metastasis often occur following radiation therapy, commonly due to the generation of radio-resistance through deregulation of the cell cycle, cell death, and inhibition of DNA damage repair mechanisms. Thus, chemotherapeutic/immunotherapeutic treatment systems have progressed remarkably in the latest years owing to destroying tumors, noninvasive, and affordable charge of therapy. But, traditional chemotherapeutic approaches target the DNA of mutated and normal healthy cells, resulting in a significantly increased risk of toxicity and drug resistance. Thus, many receptors targeted therapies are in the developmental phase of discovery. Cancer cells have a specialized set of surface receptors that provide potential targets for cancer therapeutics. Cell surface receptor-dependent endocytosis is well a known major mechanism for the internalization of macromolecular drugs. This review emphasizes the recent development of several surface receptors mediated cancer-targeting approaches for the effective delivery of various therapeutic formulations.