University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 5-2017 Combating malignant melanoma with the multifaceted soy- dervied peptide lunasin. Christopher Paul Shidal University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Part of the Medical Pharmacology Commons Recommended Citation Shidal, Christopher Paul, "Combating malignant melanoma with the multifaceted soy-dervied peptide lunasin." (2017). Electronic Theses and Dissertations. Paper 2713. https://doi.org/10.18297/etd/2713 This Doctoral Dissertation is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. COMBATING MALIGNANT MELANOMA WITH THE MULTIFACETED SOY-DERIVED PEPTIDE LUNASIN By Christopher Paul Shidal B.S., University of Kentucky, 2008 M.S., University of Louisville, 2014 A Dissertation Submitted to the Faculty of the School of Medicine of the University of Louisville In Partial Fulfillment of the Requirements For the Degree of Doctor of Philosophy in Pharmacology and Toxicology Department of Pharmacology and Toxicology University of Louisville Louisville, KY May 2017 COMBATING MALIGNANT MELANOMA WITH THE MULTIFACETED SOY-DERIVED PEPTIDE LUNASIN By Christopher Paul Shidal A Dissertation Approved on April 24, 2017 By the following Dissertation Committee: _______________________________________ Keith R. Davis, PhD _______________________________________ J. Christopher States, PhD _______________________________________ Brian P. Ceresa, PhD _______________________________________ Kavitha Yaddanapudi, PhD _______________________________________ Geoffrey J. Clark, PhD ii ACKNOWLEDGMENTS I would like to thank my mentor, Dr. Keith R. Davis, for his guidance, patience, and support throughout this entire process. I would like to thank the committee members who agreed to serve on my graduate committee and offered invaluable advice and support. I would also like to acknowledge Christiane Hassel at the IU Flow Cytometry Core, Jim Powers at the IU Light Microscopy Imaging Center, and Sue Childress at the IU Medical Sciences program for their technical support and training used throughout this dissertation. I extend a big thank you to all of my lab mates throughout the years; Elizabeth McConnell, Banu Vuyyuri, Numan Al-Rayaan, Bharat Devapatala, Calvin Koukam, and Amanda Lasnik for their friendship, training, and dedication to developing me as a scientist. Finally, I wish to thank all of my friends and family that have endured this journey with me, and especially my fiancée, Lauren Jones, for her unconditional love and unwavering support. iii ABSTRACT COMBATING MALIGNANT MELANOMA WITH THE MULTIFACETED SOY-DERIVED PEPTIDE LUNASIN Christopher P. Shidal April 24, 2017 Lunasin is a 44 amino acid peptide that has been shown to have cancer chemopreventative and chemotherapeutic properties. This study investigated the potential utility of Lunasin as a chemotherapeutic in melanomas. Studies showed that Lunasin had little activity against established melanoma cell lines using adherent culture methods; however, Lunasin’s in vitro activity was significantly higher in non- adherent colony-forming assays and oncosphere formation. These results led to the investigation of whether or not Lunasin has selective effects on cancer initiating cells (CIC) that are known to be present in melanomas. It was revealed that Lunasin selectively inhibited the proliferation of high-ALDH expressing CICs, and prevented oncosphere formation. In vitro results were extended into mouse xenograft studies using parental cells and isolated CICs. Lunasin significantly inhibited tumor growth in both cases, with the highest inhibition being observed in tumors initiated by CICs while achieving an excellent safety profile. Lunasin reduced the invasive potential of CICs in vitro and in an in vivo experimental metastasis model. Mechanistic studies revealed that Lunasin may disrupt integrin signaling by inhibiting phosphorylations of the intracellular kinase FAK as well as altering the PI3K/AKT axis. Additionally, it was demonstrated that histone acetylation in H3 and H4 core histone are significantly altered in CICs treated with Lunasin. While histone acetylation is potentially involved in Lunasin’s anticancer activity, the effects seen in these studies are mainly integrin-driven. These studies demonstrate that Lunasin has activity against putative CICs, and that Lunasin has potential utility as a therapeutic in treating malignant melanomas. iv TABLE OF CONTENTS PAGE ACKNOWLEDGEMENTS…………………………………………………………………………….....iii ABSTRACT…………………………………………………………………………………………….....iv LIST OF FIGURES………………………………………………….………………………………….....ix CHAPTER 1. INTRODUCTION…………………………………………………………………………………….....1 1.1. Background and rationale for the study...……………………………………………………...…..1 1.1.1.1. Lunasin as an anticancer agent……...…………..……..………….……....……...……1 1.1.1.2. Integrins as a therapeutic target in melanoma patients…..……………………………5 1.1.1.3. Melanoma and the presence of melanoma stem cells…………...………………….....8 1.1.1.4. Traditional approaches to treating melanomas and future perspectives..…...….…....12 1.2. Specific aims and goals of the dissertation……………………………………………………….14 1.2.1.1. Identify the mechanisms in which Lunasin exerts its anticancer effects in melanoma…………………………………………………………………………….14 1.2.1.2. Evaluate the interaction between Lunasin and integrin subunits…………...………..15 1.2.1.3. Investigate the antimetastatic effects of Lunasin……...…...……...…………………16 2. EXPERIMENTAL PROCEDURES AND METHODOLOGY…………..……………………...…….17 2.1. Isolation and purification of Lunasin…………………………………………...………………...17 2.2. Cell culture and reagents…………………………………………………………………….……18 2.3. Proliferation assays……………………………………………………………………………….19 2.4. Soft agar colony forming assays………………………………………………………………….19 2.5. ALDEFLUOR staining………………...…………………………………………………………20 2.6. Flow Cytometry (Apoptosis)……………………………………………………………………..20 2.7. Flow cytometry (Cell Cycle)……………………………………………………………………..22 2.8. Fluorescence-assisted cell sorting (FACS)……………………………………………………….22 v 2.9. Formation of multicellular oncospheres………………………………………………………….22 2.10. In vivo xenograft model…………………………………………………………………………..23 2.11. SDS-PAGE and immunoblot……………………………………………………………………..25 2.12. Non-steroidal anti-inflammatory drug (NSAID) toxicological panel and complete blood count (CBC)……………………………………………………………………………………………..26 2.13. In vivo Limiting Dilution Assay and ALDH Activity in Primary Tumors………………………27 2.14. Β-Galactosidase staining………………………………………………………………………….27 2.15. Liquid overlay generation of multicellular tumor spheres………………………………………..28 2.16. Microarray………………………………………………………………………………………..28 2.17. Immunofluorescence……………………………………………………………………………..28 2.18. Proximity ligation assay…………………………………………………………………………..29 2.19. Transwell invasion assay…………………………………………………………………………30 2.20. Murine model of experimental metastasis………………………………………………………..30 2.21. Histology………………………………………………………………………………………….31 2.22. Differentiation of ALDHhigh cells…………………………………………………………………31 2.23. Statistical analysis………………………………………………………………………………...31 3. LUNASIN IS A NOVEL THERAPEUTIC FOR TARGETING MELANOMA STEM CELLS….….33 3.1. Introduction…………………………………………………………………………………….…33 3.2. Materials and methods……………………………………………………………………………34 3.3. Results…………………………………………………………………………………………….36 3.3.1.1. Lunasin inhibits anchorage-independent growth in human melanoma cell lines …...36 3.3.1.2. Lunasin inhibits tumor growth of melanoma cells in vivo ………………………….36 3.3.1.3. Lunasin reduces the melanoma CIC subpopulation in established cell lines ……….38 3.3.1.4. Lunasin suppresses the functional properties of melanoma CICs ………...…...……41 3.3.1.5. Lunasin limits in vivo growth of tumors initiated by melanoma CIC-enriched ALDHhigh cells ……………………………………………………………...…..……41 3.3.1.6. Limiting dilution assays demonstrate differential growth patterns between ALDHhigh and ALDHlow phenotypes………………………………………...…………………..44 vi 3.3.1.7. CIC markers are heterogeneously expressed in different melanoma cell lines...……46 3.3.1.8. Lunasin induces expression of differentiation markers in melanoma CICs…………48 3.3.1.9. Lunasin did not induce a significant senescent response in ALDHhigh melanoma cells…………………………………………………………………………………..50 3.3.1.10. Lunasin may enhance the efficacy of vemurafenib in vemurafenib-resistant melanomas……...…………………………………………………………………….53 3.4. Discussion………………………………………………………………………………………...57 4. LUNASIN REDUCES THE METASTATIC POTENTIAL OF MALIGNANT MELANOMAS BY INHIBITING INTEGRIN SIGNALING AND ALTERING HISTONE ACETYLATION………..…63 4.1. Introduction………………………………………………………………………………………63 4.2. Materials and methods……………………………………………………………………………66 4.3. Results…………………………………………………………………………………………….69 4.3.1.1. Microarray reveals Lunasin-targeted genes and identifies a unique gene signature in high ALDH melanoma cells compared to parental cells …………………...………….69 4.3.1.2. Lunasin uptake correlates with expression of αV integrin subunits…….………..…..85 4.3.1.3. B16-F10 CIC populations were reduced with Lunasin treatment……………………86 4.3.1.4. Lunasin inhibits invasion of ALDHhigh melanoma stem