Tea Polysaccharide Prevents Colitis-Associated Carcinogenesis in Mice by Inhibiting the Proliferation and Invasion of Tumor Cells

Abstract

The imbalance between cell proliferation and apoptosis can lead to tumor progression, causing oncogenic transformation, abnormal cell proliferation and cell apoptosis suppression. Tea polysaccharide (TPS) is the major bioactive component in green tea, it has showed antioxidant, antitumor and anti-inflammatory bioactivities. In this study, the chemoprophylaxis effects of TPS on colitis-associated colon carcinogenesis, especially the cell apoptosis activation and inhibition effects on cell proliferation and invasion were analyzed. The azoxymethane/dextran sulfate sodium (AOM/DSS) was used to induce the colorectal carcinogenesis in mice. Results showed that the tumor incidence was reduced in TPS-treated AOM/DSS mice compared to AOM/DSS mice. TUNEL staining and Ki-67 immunohistochemistry staining showed that the TPS treatment increased significantly the cell apoptosis and decreased cell proliferation among AOM/DSS mice. Furthermore, TPS reduced the expression levels of the cell cycle protein cyclin D1, matrix metalloproteinase (MMP)-2, and MMP-9. In addition, in vitro studies showed that TPS, suppressed the proliferation and invasion of the mouse colon cancer cells. Overall, our findings demonstrated that TPS could be a potential agent in the treatment and/or prevention of colon tumor, which promoted the apoptosis and suppressed the proliferation and invasion of the mouse colon cancer cells via arresting cell cycle progression.

Dietary Supplementation of Selenoneine-Containing Tuna Dark Muscle Extract Effectively Reduces Pathology of Experimental Colorectal Cancers in Mice

“…Excessive ROS production induces aberrant NF-κB activation that cause inflammatory bowel disease (IBD) or colitis-associated cancer (CAC) [ 12 , 13 ]. Some studies have shown that the intake of antioxidants inhibits IBD and CAC in mouse models [ 14 , 15 , 16 ]. In particular, the antioxidant ergothioneine scavenges intestinal oxidative stress after intracellular uptake by the organic carnitine transporter (OCTN1), which is expressed in the intestine [ 17 ].…”

Tea bioactive components prevent carcinogenesis via anti‐pathogen, anti‐inflammation, and cell survival pathways

“…The effective components in tea can cause cell cycle arrest, and inhibit the proliferation of cancer cells (Figure 4). Tea polysaccharides from green tea can arrest the cell cycle via the down‐regulation of cyclin D1 in AOM/DSS‐induced colorectal carcinogenesis in mice, 33,34 make MCF‐7 cancer cells undergo G2/M phase arrest by up‐regulating p53 (also known as a tumor suppressor gene), 29 and reduce cell proliferation through down‐regulating the Akt/ERK signaling pathway in prostate cancer cells and tissues 75 . Theaflavins and thearubigins can induce cell cycle arrest at the G0/G1 or G1/S phase in human leukemic cells (U937 and K562) and ovarian cancer cells (A2780/CP70 and OVCAR‐3) by ablating cyclin‐dependent kinases (CDKs) and cyclin D1 levels, which were regulated by heat shock protein (HSP) 90, protein kinase B (Akt) signaling, wingless‐type MMTV integration site family (Wnt)/β‐catenin signaling, p21 and forkhead transcription factor 1 (FOXO1) 76,77 .…”

“…[22][23][24] Moreover, the anti-cancer activity of tea mainly depends on its functional constituents. Several in vivo and in vitro studies have shown that tea polyphenols (especially epigallocatechin-3-gallate [EGCG]), [25][26][27][28] tea polysaccharides, [29][30][31][32][33][34] Ltheanine, [35][36][37] tea pigments, 38 and caffeine 39,40 can inhibit the occurrence and development of cancers. Conversely, there are few studies focused on the minor constituents (such as tea saponin, tea protein, vitamins, fat, trace elements, γ-aminobutyric acid, and enzymes) and their potential to prevent cancer.…”

Metformin and Probiotics in the Crosstalk between Colitis-Associated Colorectal Cancer and Diabetes in Mice

“…The nuclei were counterstained with DAPI and slides were photographed using Zeiss Axio microscope. Sections were evaluated focusing on longitudinally oriented crypts and the number of Ki-67-positive cells per HPF (40× objective) were counted [61,62].…”