Development of Tat-fused drug binding protein to improve anti-cancer effect of mammalian target of rapamycin inhibitors

• Published in: Biotechnology and bioprocess engineering Vol. 29; no. 2; pp. 303 - 312
• Main Authors: Lim, Su Yeon, Kim, Sugyeong, Kim, Hongbin, Kim, Hyun-Ouk, Ha, Suk-Jin, Lim, Kwang Suk
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Society for Biotechnology and Bioengineering 01.04.2024; Springer Nature B.V
• Subjects: Anticancer properties; antineoplastic activity; Biotechnology; Breast cancer; breast neoplasms; Cancer; cell cycle; cell growth; Chemistry; Chemistry and Materials Science; Conjugation; domain; Fusion protein; genetic vectors; humans; Industrial and Production Engineering; Inhibitor drugs; Inhibitors; Mammals; Proteins; Rapamycin; recombinant fusion proteins; Research Paper; Signal transduction; System effectiveness; TOR protein; Mammalian target of rapamycin inhibitors; Recombinant fusion protein; Protein transduction domains; Self-assemble
• ISSN: 1226-8372; 1976-3816
• DOI: 10.1007/s12257-024-00015-7

The mammalian target of rapamycin (mTOR) is known to regulate cell growth, protein stability and cell-cycle progression, and many human tumors result from the dysregulation of mTOR signaling. Although various mTOR inhibitors have been developed, effective delivery systems are still needed to enhance the anti-cancer effects of mTOR inhibitors. In this study, we developed the Tat-fused mTOR inhibitor binding domain (Tat-MBD/TMBD) for the enhancement of the anti-cancer effect of mTOR inhibitors, due to the improvement of intracellular uptake. A TMBD/mTOR inhibitors complex spontaneously formed by biological affinity between MBD and mTOR inhibitors without chemical conjugation and modification. We constructed that a recombinant fusion protein expression vector composed of Tat (protein transduction domain) and mTOR inhibitor-binding domain (Tat-MBD) to deliver the mTOR inhibitors. The MBD spontaneously bound with mTOR inhibitors including sirolimus, everolimus, and temsirolimus, resulting in the formation of a TMBD/mTOR inhibitors complex. The enhancement of the delivery efficacy of mTOR inhibitors into various breast cancer cells was confirmed and improved anti-cancer efficacy was observed. We demonstrated the effective delivery systems of mTOR inhibitors without chemical conjugation of mTOR inhibitors.