Exploring the role of polymeric conjugates toward anti-cancer drug delivery: Current trends and future projections.

Utilizing the diverse features of biocompatible polymers to target drugs into the tumor/s has been a research hotspot since last decade. Such polymeric conjugates of anti-cancer drugs have proven their potential in providing sustained release of drugs with reduced systemic toxicity and improved tumor retention. Polymers like polyethylene glycol (PEG), N-(2-Hydroxypropyl) methacrylamide (HPMA), Polylactic-co-glycolic acid (PLGA), Polyamidoamine (PAMAM), and others remain exploited for their specific as well as shared characteristics in the rational delivery of anti-cancer agents. Variable nano size, attachment with tumor-specific proteins, responsiveness to stimuli and ability to deliver a wide range of molecules like drugs, antibodies and peptides are some of the achievements of polymeric nano-conjugates so far. Many such conjugates have shown potential clinically which has attracted the researchers and promoted further advancements of the technique. Apart from achievements the polymeric conjugates suffer from shortcomings like poor drug loading and chances of potential chronic-systemic toxicities. The review highlights key findings of research in recent time and advancements taking place in the field of polymeric conjugates of anti-cancer drugs along with the limitations. We have also emphasized on newer and relatively less explored applications of tumor-targeted polymeric conjugates which can add new dimensions to this technique.