Tumor Microenvironment Sensing and Drug Delivery

The tumor microenvironment is the cellular environment in which the tumor exists, including surrounding blood vessels, immune cells, fibroblasts, bone marrow-derived inflammatory cells, lymphocytes, signaling molecules, and the extracellular matrix. The tumor microenvironment contributes to tumour heterogeneity. Our group is using the tumour heterogeneity as a new and competent tool for cell-specific targeted drug delivery and cancer treatment.

pH Sensing and Drug Delivery:

Cancer thrives in an acidic environment and doesn't survive in a normal, more alkaline environment. Cancer cells make our body even more acidic as they produce lactic acid. Our group has utilized this tumor microenvironment to develop pH sensing and drug delivery systems. We developed an ESIPT based drug delivery system for pH sensitive fluorescence properties and photocontrolled release of the anticancer drug chlorambucil.

Metal Ion sensing and Drug Delivery:

According to past research, healthy human prostate accumulates the highest level of zinc of any soft tissue in the body. But on the contrary, with the development of malignancy, there is a dramatic reduction in the zinc content of prostate tissue, associated with the inability of cancer cells to accumulate zinc. Our group has developed a system that first guided us to locate the diseased area by using cellular zinc concentration as a biomarker followed by the on-demand release of anticancer drug chlorambucil by employing the external stimulus, light.

Glutathione Sensing and Drug Delivery:

Biological thiols, including glutathione(GSH), cysteine (Cys), and homocysteine (Hcy), play crucial roles in maintaining the appropriate redox status of biological systems. GSH is the most abundant cellular thiol, which is important for maintaining a cellular defense against free radicals and reactive oxygen species (ROS), and it also maintains exogenous antioxidants in their reduced forms. Our group has designed a redox-responsive drug delivery system (DDS) to exploit the higher level of thiols in tumor sites to trigger the release of drug from the DDS.