Research Advances on Tumor Microenvironment Responsive Nano-Preparations

Tumor microenvironment responsive nano-preparations enhancing tumor cellular uptake and triggering drug release at the target site have emerged as one of the most effective strategies for cancer treatments. The tumor microenvironment includes slightly acidic environments, matrix metalloproteases, lysosomal enzymes, high glutathione levels in the cytoplasm and cell nucleus, which have been used as the potential internal stimuli to activate responsive release in the tumor sites or cancer cells. This method can improve the biodistribution and reduce the side-effects of active drugs. This review highlights the mechanism, design and recent developments of pH, enzyme, reduction and thermal responsive nano-preparations so as to provide reference information for further development of anticancer nano-preparations.