Rational Drug Design of Targeted and Enzyme Cleavable Vitamin E Analogs as Neoadjuvant to Chemotherapy: In Vitro and In Vivo Evaluation on Reduction of Cardiotoxicity of Doxorubicin.

Traditional drug design focus on specific target (s) expressed by cancer cells. However, cancer cells outsmart the interventions by activating survival pathways and/or downregulating cell death pathways. As the research in molecular biology of cancer grows exponentially, new methods of drug designs are needed to target multiple pathways/targets which are involved in survival of cancer cells. Vitamin E analogues including a-tocopheryl succinate (-TOS) is a well-known anti-tumoregenic agent which is well studied both in vitro and in vivo tumor models. However, lack of targeting cancer cells and unexpected toxicity along with the poor water solubility of -TOS compelled a rational drug design using both targeting and cleavable technologies incorporated in the new drug design. A plethora of Vitamin E derivatives (AMP-001, 002 and 003) were synthesized, characterized and studied for the improved efficacy and lowered toxicity in various cancer cells in vitro. Preliminary studies revealed AAAPT leading candidates reduced the invasive potential of brain tumor stem cells, synergized with different drugs and different treatments. AAAPT leading drug AMP-001 enhanced the therapeutic index of front-line drug Doxorubicin in triple negative breast cancer (TNBC) tumor rat model preserving the ventricular function when used as a neoadjuvant to Doxorubicin. These results may pave the way for reducing the cardiotoxicity of chemotherapy in clinical settings.