{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T09:52:42Z","timestamp":1786960362794,"version":"build-2736575974"},"reference-count":35,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,18]],"date-time":"2022-06-18T00:00:00Z","timestamp":1655510400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000002","name":"US National Institutes of Health","doi-asserted-by":"publisher","award":["CA204345"],"award-info":[{"award-number":["CA204345"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"US National Institutes of Health","doi-asserted-by":"publisher","award":["CA235863"],"award-info":[{"award-number":["CA235863"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"US National Institutes of Health","doi-asserted-by":"publisher","award":["MDBR-20-135-SRS"],"award-info":[{"award-number":["MDBR-20-135-SRS"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Samuel Waxman Cancer Research Foundation","award":["CA204345"],"award-info":[{"award-number":["CA204345"]}]},{"name":"the Samuel Waxman Cancer Research Foundation","award":["CA235863"],"award-info":[{"award-number":["CA235863"]}]},{"name":"the Samuel Waxman Cancer Research Foundation","award":["MDBR-20-135-SRS"],"award-info":[{"award-number":["MDBR-20-135-SRS"]}]},{"name":"the University of Pennsylvania Orphan Disease Center Million Dollar Bike Ride","award":["CA204345"],"award-info":[{"award-number":["CA204345"]}]},{"name":"the University of Pennsylvania Orphan Disease Center Million Dollar Bike Ride","award":["CA235863"],"award-info":[{"award-number":["CA235863"]}]},{"name":"the University of Pennsylvania Orphan Disease Center Million Dollar Bike Ride","award":["MDBR-20-135-SRS"],"award-info":[{"award-number":["MDBR-20-135-SRS"]}]},{"name":"the Chan Zuckerberg Initiative","award":["CA204345"],"award-info":[{"award-number":["CA204345"]}]},{"name":"the Chan Zuckerberg Initiative","award":["CA235863"],"award-info":[{"award-number":["CA235863"]}]},{"name":"the Chan Zuckerberg Initiative","award":["MDBR-20-135-SRS"],"award-info":[{"award-number":["MDBR-20-135-SRS"]}]},{"name":"Panbela Therapeutics Inc.","award":["CA204345"],"award-info":[{"award-number":["CA204345"]}]},{"name":"Panbela Therapeutics Inc.","award":["CA235863"],"award-info":[{"award-number":["CA235863"]}]},{"name":"Panbela Therapeutics Inc.","award":["MDBR-20-135-SRS"],"award-info":[{"award-number":["MDBR-20-135-SRS"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Naturally occurring polyamines are absolutely required for cellular growth and proliferation. Many neoplastic cells are reliant on elevated polyamine levels and maintain these levels through dysregulated polyamine metabolism. The modulation of polyamine metabolism is thus a promising avenue for cancer therapeutics and has been attempted with numerous molecules, including enzyme inhibitors and polyamine analogues. SBP-101 (diethyl dihydroxyhomospermine) is a spermine analogue that has shown efficacy in slowing pancreatic tumor progression both in vitro and in vivo; however, the mechanisms underlying these effects remain unclear. We determined the effects of the SBP-101 treatment on a variety of cancer cell types in vitro, including lung, pancreatic, and ovarian. We evaluated the activity of enzymes involved in polyamine metabolism and the effect on intracellular polyamine pools following the SBP-101 treatment. The SBP-101 treatment produced a modest but variable increase in polyamine catabolism; however, a robust downregulation of the activity of the biosynthetic enzyme, ornithine decarboxylase (ODC), was seen across all of the cell types studied and indicates that SBP-101 likely exerts its effect predominately through the downregulation of ODC, with a minor upregulation of catabolism. Our in vitro work indicated that SBP-101 was most toxic in the tested ovarian cell lines. Therefore, we evaluated the efficacy of SBP-101 as a monotherapy in the immunosuppressive VDID8+ murine ovarian model. Mice treated with SBP-101 demonstrated a delay in tumor progression, a decrease in the overall tumor burden, and a marked increase in median survival.<\/jats:p>","DOI":"10.3390\/ijms23126798","type":"journal-article","created":{"date-parts":[[2022,6,18]],"date-time":"2022-06-18T09:51:11Z","timestamp":1655545871000},"page":"6798","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Expanded Potential of the Polyamine Analogue SBP-101 (Diethyl Dihydroxyhomospermine) as a Modulator of Polyamine Metabolism and Cancer Therapeutic"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4869-1301","authenticated-orcid":false,"given":"Cassandra E.","family":"Holbert","sequence":"first","affiliation":[{"name":"Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21231, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jackson R.","family":"Foley","sequence":"additional","affiliation":[{"name":"Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21231, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8679-6414","authenticated-orcid":false,"given":"Tracy","family":"Murray Stewart","sequence":"additional","affiliation":[{"name":"Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21231, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"suffix":"Jr.","given":"Robert A.","family":"Casero","sequence":"additional","affiliation":[{"name":"Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD 21231, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"880","DOI":"10.1002\/iub.230","article-title":"Mammalian polyamine metabolism and function","volume":"61","author":"Pegg","year":"2009","journal-title":"IUBMB Life"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1149","DOI":"10.1080\/07391102.1988.10506455","article-title":"Polyamine-DNA Interactions. 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