A CARP-1 functional mimetic loaded vitamin E-TPGS micellar nano-formulation for inhibition of renal cell carcinoma

// Vino T. Cheriyan 1, 2, * , Hashem O. Alsaab 5, 6, * , Sreeja Sekhar 1, 2 , Caitlin Stieber 2, 4, 8 , Prashant Kesharwani 5, 7 , Samaresh Sau 5 , Magesh Muthu 1, 2, 9 , Lisa A. Polin 2, 4 , Edi Levi 1, 3 , Arun K. Iyer 4, 5 and Arun K. Rishi 1, 2, 4 1 John D. Dingell VA Medical Center, Detroit, Michigan, 48201, USA 2 Department of Oncology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan, 48201, USA 3 Department of Pathology, Wayne State University School of Medicine, Detroit, Michigan, 48201, USA 4 Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan, 48201, USA 5 Use-inspired Biomaterials & Integrated Nano Delivery (U-BiND) Systems Laboratory Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, Detroit, MI 48201, USA 6 Department of Pharmaceutics and Pharmaceutical Technology, College of Pharmacy, Taif University, Taif 26571, Saudi Arabia 7 Present address: Pharmaceutics Division, CSIR-Central Drug Research Institute, Lucknow 226031, India 8 Present address: Cornell College, Mount Vernon, Iowa, 52314, USA 9 Present Address: Department of Molecular Biology, Umea University, 901 87 Umea, Sweden * These authors have contributed equally to this work Correspondence to: Arun K. Iyer, email: arun.iyer@wayne.edu Arun K. Rishi, email: rishia@Karmanos.org Keywords: RCC, CFM, CARP-1, everolimus, nano-micelles Received: April 18, 2017     Accepted: July 26, 2017     Published: September 05, 2017 ABSTRACT Current treatments for Renal Cell Carcinoma (RCC) include a combination of surgery, targeted therapy, and immunotherapy. Emergence of resistant RCCs contributes to failure of drugs and poor prognosis, and thus warrants development of new and improved treatment options for RCCs. Here we generated and characterized RCC cells that are resistant to Everolimus, a frontline mToR-targeted therapy, and tested whether our novel class of CARP-1 functional mimetic (CFM) compounds inhibit parental and Everolimus-resistant RCC cells. CFMs inhibited RCC cell viability in a dose-dependent manner that was comparable to Everolimus treatments. The GI 50 dose of Everolimus for parental A498 cells was ~1.2μM while it was <0.02μM for the parental UOK262 and UOK268 cells. The GI 50 dose for Everolimus-resistant A498, UOK262, and UOK268 cells were ≥10.0μM, 1.8-7.0μM, and 7.0-≥10.0μM, respectively. CFM-4 and its novel analog CFM-4.16 inhibited viabilities of Everolimus resistant RCC cells albeit CFM-4.16 was more effective than CFM-4. CFM-dependent loss of RCC cell viabilities was due in part to reduced cyclin B1 levels, activation of pro-apoptotic, stress-activated protein kinases (SAPKs), and apoptosis. CFM-4.16 suppressed growth of resistant RCC cells in three-dimensional suspension cultures. However, CFMs are hydrophobic and their intravenous administration and dose escalation for in-vivo studies remain challenging. In this study, we encapsulated CFM-4.16 in Vitamin-E TPGS-based- nanomicelles that resulted in its water-soluble formulation with higher CFM-4.16 loading (30% w/w). This CFM-4.16 formulation inhibited viability of parental and Everolimus-resistant RCC cells in vitro , and suppressed growth of parental A498 RCC-cell-derived xenografts in part by stimulating apoptosis. These findings portent promising therapeutic potential of CFM-4.16 for treatment of RCCs.