title: Rhamnogalacturonan I containing homogalacturonan inhibits colon cancer cell proliferation by decreasing ICAM1 expression.
abstract: Pectin modified with pH, heat or enzymes, has previously been shown to exhibit anti-cancer activity. However, the structural requirements for modified pectin bioactivity have rarely been addressed. In this study several pectin extracts representing different structural components of pectin were assessed for effects against colon cancer cells. Rhamnogalacturonan I (RGI) extracts reduced proliferation of DLD1 and HCT116 colon cancer cells in a dose- and time-dependent manner. RGI reduced ICAM1 gene expression and siRNA-mediated knockdown of ICAM1 expression decreased cell proliferation providing a potential novel mechanism for the anti-cancer activity of pectin. Structural analysis of bioactive and non-bioactive RGIs suggested that a homogalacturonan component is maybe essential for the anti-proliferative activity, furthering the understanding of the structural requirements for pectin bioactivity.
authors.affiliation: Institute of Food Research, Norwich Research Park, Colney, Norwich, NR4 7UA, UK. Electronic address: ellen.maxwell@ifr.ac.uk.
authors.forename: Ellen G
authors.initials: EG
authors.lastname: Maxwell
authors.affiliation: Institute of Food Research, Norwich Research Park, Colney, Norwich, NR4 7UA, UK. Electronic address: ian.colquhoun@ifr.ac.uk.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Colquhoun
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, 600 E Mermaid Lane, ERRC, Wyndmoor, PA 19038-8598, USA. Electronic address: hoa.chau@ars.usda.gov.
authors.forename: Hoa K
authors.initials: HK
authors.lastname: Chau
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, 600 E Mermaid Lane, ERRC, Wyndmoor, PA 19038-8598, USA. Electronic address: arland.hotchkiss@ars.usda.gov.
authors.forename: Arland T
authors.initials: AT
authors.lastname: Hotchkiss
authors.affiliation: Institute of Food Research, Norwich Research Park, Colney, Norwich, NR4 7UA, UK. Electronic address: keith.waldron@ifr.ac.uk.
authors.forename: Keith W
authors.initials: KW
authors.lastname: Waldron
authors.affiliation: Institute of Food Research, Norwich Research Park, Colney, Norwich, NR4 7UA, UK. Electronic address: vic.morris@ifr.ac.uk.
authors.forename: Victor J
authors.initials: VJ
authors.lastname: Morris
authors.affiliation: Institute of Food Research, Norwich Research Park, Colney, Norwich, NR4 7UA, UK. Electronic address: nigel.belshaw@ifr.ac.uk.
authors.forename: Nigel J
authors.initials: NJ
authors.lastname: Belshaw
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000633:toxicity; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology; D045325:HCT116 Cells; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D010368:Pectins / Q000737:chemistry* / Q000633:toxicity; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D034741:RNA, Small Interfering; C042491:rhamnogalacturonan I; D018799:Intercellular Adhesion Molecule-1; D010368:Pectins; C003181:polygalacturonic acid
keywords: Colon cancer; Galactan; Homogalacturonan; ICAM1; Modified pectin; Rhamnogalacturonan I