Abstract
Reza Bayat Mokhtari1,2,3, Bessi Qorri3, Narges Baluch4, Angelo Sparaneo5, Federico Pio Fabrizio5, Lucia Anna Muscarella5, Albina Tyker6, Sushil Kumar7, Hai-Ling Margaret Cheng8, Myron R. Szewczuk3, Bikul Das2,9,10 and Herman Yeger1
1 Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
2 Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA, USA
3 Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
4 Department of Immunology and Allergy, The Hospital for Sick Children, Toronto, Ontario, Canada
5 Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
6 Department of Internal Medicine, University of Chicago, Chicago, IL, USA
7 Q.P.S. Holdings LLC, Pencader Corporate Center, Newark, DE, USA
8 Institute of Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, Canada
9 Department of Cancer and Stem Cell Biology, KaviKrishna Laboratory, Guwahati Biotech Park, Indian Institute of Technology, Guwahati, Assam, India
10 Department of Immunology and Infectious Diseases, Forsyth Institute, Cambridge, MA, USA
Correspondence to:
Herman Yeger, | email: | hermie@sickkids.ca |
Reza Bayat Mokhtari, | email: | rbm7@queensu.ca |
Myron R. Szewczuk, | email: | szewczuk@queensu.ca |
Keywords: sulforaphane; acetazolamide; bronchial carcinoid tumors; serotonin; carbonic anhydrase
Received: May 29, 2021 Accepted: June 14, 2021 Published: July 20, 2021
ABSTRACT
Objective: Aberrations in the PI3K/AKT/mTOR survival pathway in many cancers are the most common genomic abnormalities. The phytochemical and bioactive agent sulforaphane (SFN) has nutrigenomic potential in activating the expression of several cellular protective genes via the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 is primarily related to mechanisms of endogenous cellular defense and survival. The efficacy of SFN in combination with acetazolamide (AZ) was investigated in reducing typical H727 and atypical H720 BC survival, migration potential, and apoptosis in vitro and in vivo preclinical xenograft tissues.
Materials and Methods: Microscopic imaging, immunocytochemistry, wound healing assay, caspase-cleaved cytokeratin 18 (M30, CCK18) CytoDeath ELISA assay, immunofluorescence labeling assays for apoptosis, hypoxia, Western Blotting, Tunnel assay, measurement of 5-HT secretion by carbon fiber amperometry assay, quantitative methylation-specific PCR (qMSP), morphologic changes, cell viability, apoptosis activity and the expression levels of phospho-Akt1, Akt1, HIF-1α, PI3K, p21, CAIX, 5-HT, phospho-mTOR, and mTOR in xenografts derived from typical H727 and atypical H720 BC cell lines.
Results: Combining AZ+SFN reduced tumor cell survival compared to each agent alone, both in vitro and in vivo xenograft tissues. AZ+SFN targeted multiple pathways involved in cell cycle, serotonin secretion, survival, and growth pathways, highlighting its therapeutic approach. Both H727 and H720 cells were associated with induction of apoptosis, upregulation of the p21 cell cycle inhibitor, and downregulation of the PI3K/Akt/mTOR pathway, suggesting that the PI3K/Akt/mTOR pathway is a primary target of the AZ+SFN combination therapy.
Conclusions: Combining SFN+AZ significantly inhibits the PI3K/Akt/mTOR pathway and significantly reducing 5-HT secretion in carcinoid syndrome.