Dr. Weeks’ Comments: Lunasin is a potent non-GMO soy extract with great science behind it.
J AOAC Int. 2008 Jul-Aug;91(4):932-5.
Lunasin: a novel cancer preventive seed peptide that modifies chromatin.
University of California, Department of Nutritional Sciences and Toxicology, 119 Morgan Hall, Berkeley, CA 94720-3104, USA. firstname.lastname@example.org
Lunasin is a novel cancer preventive peptide whose efficacy against chemical carcinogens and oncogenes has been demonstrated in mammalian cells and a skin cancer mouse model. In contrast, constitutive expression of the lunasin gene in mammalian cells leads to arrest of cell division and cell death. Isolated and characterized in soy, lunasin peptide is also documented in barley and wheat and is predicted to be present in many more seeds because of its possible role in seed development. Initial studies show that lunasin is bioavailable in mice when orally ingested. Lunasin internalizes into mammalian cells within minutes of exogenous application, and localizes in the nucleus after 18 h. It inhibits acetylation of core histones in mammalian cells but does not affect the growth rate of normal and established cancer cell lines. An epigenetic mechanism of action is proposed whereby lunasin selectively kills cells being transformed or newly transformed cells by binding to deacetylated core histones exposed by the transformation event, disrupting the dynamics of histone acetylation-deacetylation.
Cancer Lett. 2007 Sep 18;255(1):42-8. Epub 2007 May 3.
The cancer preventive peptide lunasin from wheat inhibits core histone acetylation.
College of Natural Sciences, Andong National University, Andong, Republic of Korea.
Lunasin is a unique 43-amino acid cancer preventive peptide initially reported in soybean and barley and has been shown to be chemopreventive in mammalian cells and in a skin cancer mouse model against oncogenes and chemical carcinogens. We report here the core histone H3- and H-acetylation inhibitory properties of lunasin from wheat, a new source of the peptide and from the livers of rats fed with lunasin-enriched wheat (LEW) to measure bioavailability. A non-radioactive histone acetyl transferase assay was used to measure inhibition of core histone acetylation. The presence of lunasin in wheat was established by Western blot and identified by liquid chromatography electrospray ionization mass spectrometry (LC-ESI-MS). Lunasin isolated from wheat seeds at different stages of development inhibited core histone H3 and H4 acetylation in a dose-dependent manner. Lunasin extracted from liver of rats fed with lunasin-enriched wheat (LEW) also inhibited histone acetylation confirming that the peptide is intact and bioactive. The amounts of lunasin in the developing seeds and in the rat liver correlated extremely well with the extent of inhibition of core histone acetylation.
J Agric Food Chem. 2007 Dec 26;55(26):10707-13. Epub 2007 Nov 27.
Cancer-preventive peptide lunasin from Solanum nigrum L. inhibits acetylation of core histones H3 and H4 and phosphorylation of retinoblastoma protein (Rb).
School of Bioresources Sciences, Andong National University, Korea.
Lunasin, a unique 43 amino acid, 4.8 kDa cancer-chemopreventive peptide initially reported in soybean and now found in barley and wheat, has been shown to be cancer-chemopreventive in mammalian cells and in a skin cancer mouse model against oncogenes and chemical carcinogens. To identify bioactive components in traditional herbal medicines and in search for new sources of lunasin, we report here the properties of lunasin from Solanum nigrum L. (SNL), a plant indigenous to northeast Asia. Lunasin was screened in the crude extracts of five varieties of the medicinal plants of Solanaceae origin and seven other major herbal plants. An in vitro digestion stability assay for measuring bioavailability was carried out on SNL crude protein and autoclaved SNL using pepsin and pancreatin. A nonradioactive histone acetyltransferase (HAT) assay and HAT activity colorimetric assay were used to measure the inhibition of core histone acetylation. The inhibitory effect of lunasin on the phosphorylation of retinoblastoma protein (Rb) was determined by immunoblotting against phospho-Rb. Lunasin isolated from autoclaved SNL inhibited core histone H3 and H4 acetylation, the activities of the HATs, and the phosphorylation of the Rb protein. Lunasin in the crude protein and in the autoclaved crude protein was very stable to pepsin and pancreatin in vitro digestion, while the synthetic pure lunasin was digested at 2 min after the reaction. We conclude that lunasin is a bioactive and bioavailable component in SNL and that consumption of SNL may play an important role in cancer prevention.
My current research interest is to identify and monitor global and localized changes in epigenetic marks and chromatin modifications (i.e. H3-K14ac, H4-K16ac, PCAF occupancy, DNA methylation) associated with androgen treatment and prostate cancer formation by developing ChIP-based and microRNA genomic assays. A secondary goal is to further characterize the chemopreventive effects of the dietary soy peptide, lunasin, on prostate cancer based on its chromatin binding property and epigenetic mechanism of action. I serendipitously discovered the anti-mitotic effect of the lunasin gene and the cancer preventive and chromatin binding properties of the lunasin peptide while I was a postdoctoral scientist at UC Berkeley. My work outside of academia has led to the development of putative modified peptides as potential anti-cancer therapeutics, identification of the lunasin peptide as the active component in soy protein responsible for its LDL-cholesterol lowering property and the commercial development of lunasin-optimized soy protein extracts for the nutraceutical, cosmeceutical and functional food industry. I am currently extending my work at UC Davis to understand the chemopreventive mechanism of action of the lunasin peptide against prostate cancer and build on previous results from whole genome expression studies and novel discoveries. These include the characterization of the differential epigenetic effect of lunasin on normal and tumor prostate cells, the discovery that lunasin upregulates UGT1A1 in liver cells, and the discovery of lunasin as a dietary peptidomimetic, with structural and functional similarity to the human tumor suppressor, ANP32A, f