Anthropogenic Transmission of SARS-CoV-2 from Humans to Lions, Singapore, 2021.

In Singapore, 10 captive lions tested positive for SARS-CoV-2 by real-time PCR. Genomic analyses of nanopore sequencing confirmed human-to-animal transmission of the SARS-CoV-2 Delta variant. Viral genomes from the lions and zookeeper shared a unique spike protein substitution, S:A1016V. Widespread SARS-CoV-2 transmission among humans can increase the likelihood of anthroponosis.

Detection of African Swine Fever Virus from Wild Boar, Singapore, 2023.

We detected African swine fever virus (ASFV) from a wild boar in Singapore. In <72 hours, we confirmed and reported ASFV p72 genotype II, CD2v serogroup 8, and IGR-II variant by using a combination of real-time PCR and whole-genome sequencing. Continued biosurveillance will be needed to monitor ASFV in Singapore.

Genomes From Historic DNA Unveil Massive Hidden Extinction and Terminal Endangerment in a Tropical Asian Songbird Radiation.

Quantifying the magnitude of the global extinction crisis is important but remains challenging, as many extinction events pass unnoticed owing to our limited taxonomic knowledge of the world's organisms. The increasing rarity of many taxa renders comprehensive sampling difficult, further compounding the problem. Vertebrate lineages such as birds, which are thought to be taxonomically well understood, are therefore used as indicator groups for mapping and quantifying global extinction. To test whether extinction patterns are adequately gauged in well-studied groups, we implemented ancient-DNA protocols and retrieved whole genomes from the historic DNA of museum specimens in a widely known songbird radiation of shamas (genus Copsychus) that is assumed to be of least conservation concern. We uncovered cryptic diversity and an unexpected degree of hidden extinction and terminal endangerment. Our analyses reveal that >40% of the phylogenetic diversity of this radiation is already either extinct in the wild or nearly so, including the two genomically most distinct members of this group (omissus and nigricauda), which have so far flown under the conservation radar as they have previously been considered subspecies. Comparing the genomes of modern samples with those from roughly a century ago, we also found a significant decrease in genetic diversity and a concomitant increase in homozygosity affecting various taxa, including small-island endemics that are extinct in the wild as well as subspecies that remain widespread across the continental scale. Our application of modern genomic approaches demonstrates elevated levels of allelic and taxonomic diversity loss in a songbird clade that has not been listed as globally threatened, highlighting the importance of ongoing reassessments of extinction incidence even across well-studied animal groups. Key words: extinction, introgression, white-rumped shama, conservation.

The effect of Andrographis paniculata water extract on palliative management of metastatic esophageal squamous cell carcinoma-A phase II clinical trial.

Patients with metastatic esophageal squamous cell carcinoma (ESCC) have a grave prognosis with limited life expectancy. Here, a phase II clinical trial was conducted to investigate the effect of Andrographis paniculata (AP) on the palliative care of patients with metastatic ESCC. Patients with metastatic or locally advanced ESCC deemed unfit for surgery, and who have already completed palliative chemotherapy or chemoradiotherapy or are not fit for these treatments, were recruited. These patients were prescribed AP concentrated granules for 4 months. They also received clinical and quality of life assessments for clinical response, as well as positron emission tomography-computed tomography at 3 and 6 months after AP treatment for the assessment of tumor volume. Furthermore, the change in gut microbiota composition after AP treatment was studied. From the results, among the 30 recruited patients, 10 completed the entire course of AP treatment, while 20 received partial AP treatment. Patients who completed the AP treatment achieved significantly longer overall survival periods with the maintenance of the quality of life during the survival period when compared to those who could not complete AP treatment. The treatment effect of AP also contributed to the shift of the overall structure of gut microbiota for ESCC patients towards those of healthy individuals. The significance of this study is the establishment of AP as a safe and effective palliative treatment for patients with squamous cell carcinoma of the esophagus. To the best of our knowledge, this is the first clinical trial of AP water extract in esophageal cancer patients demonstrating its new medicinal use.

The Application of Adipose Tissue-Derived Mesenchymal Stem Cells (ADMSCs) and a Twin-Herb Formula to the Rodent Wound Healing Model: Use Alone or Together?

Our previous study reported that mesenchymal stem cells (MSCs) accelerated the wound healing process through anti-inflammatory, anti-apoptotic, and pro-angiogenetic effects in a rodent skin excision model. NF3 is a twin-herb formula, which presents similar effects in promoting wound healing. Research focusing on the interaction of MSCs and Chinese medicine is limited. In this study, we applied MSCs and the twin-herb formula to the wound healing model and investigated their interactions. Wound healing was improved in all treatment groups (MSCs only, NF3 only, and MSCs + NF3). The combined therapy further enhanced the effect: more GFP-labelled ADMSCs, collagen I and collagen III expression, Sox9 positive cells, and CD31 positive cells, along with less ED-1 positive cells, were detected; the expressions of proinflammatory cytokine IL-6 and TNF-α were downregulated; and the expression of anti-inflammatory cytokine IL-10 was upregulated. In vitro, NF3 promoted the cell viability and proliferation ability of MSCs, and a higher concentration of protein was detected in the NF3-treated supernatant. A proteomic analysis showed there were 15 and 22 proteins in the supernatants of normal ADMSCs and NF3-treated ADMSCs, respectively. After PCR validation, the expressions of 11 related genes were upregulated. The results of a western blot suggested that the TGFß/Smad and Wnt pathways were related to the therapeutic effects of the combined treatment. Our study suggests for the first time that NF3 enhanced the therapeutic effect of MSCs in the wound healing model and the TGFß/Smad and Wnt pathways were related to the procedure.

Creating a Vaccine-like Supplement against Respiratory Infection Using Recombinant Bacillus subtilis Spores Expressing SARS-CoV-2 Spike Protein with Natural Products.

Vaccination is the most effective method of combating COVID-19 infection, but people with a psychological fear of needles and side effects are hesitant to receive the current vaccination, and alternative delivery methods may help. Bacillus subtilis, a harmless intestinal commensal, has recently earned a strong reputation as a vaccine production host and delivery vector, with advantages such as low cost, safety for human consumption, and straightforward oral administration. In this study, we have succeeded generating "S spores" by engineering B. subtilis with spore coat proteins resembling the spike (S) protein of the ancestral SARS-CoV-2 coronavirus. With the addition of two immunostimulating natural products as adjuvants, namely Astragalus membranaceus (Fisch.) Bge (AM) and Coriolus versicolor (CV), oral administration of S spores could elicit mild immune responses against COVID-19 infection without toxicity. Mucosal IgA against the S protein was enhanced by co-feeding with AM and CV in an S spores-inoculated mouse model. Faster and stronger IgG responses against the S protein were observed when the mice were fed with S spores prior to vaccination with the commercial COVID-19 vaccine CoronaVac. In vitro studies demonstrated that AM, CV, and B. subtilis spores could dose-dependently activate both macrophages and dendritic cells by secreting innate immunity-related IL-1ß, IL-6, and TNF-α, and some other proinflammatory chemokines and cytokines. In conclusion, the combination of S spores with AM and CV may be helpful in developing a vaccine-like supplement against respiratory infection.

A review on the molecular mechanisms, the therapeutic treatment including the potential of herbs and natural products, and target prediction of obesity-associated colorectal cancer.

Colorectal cancer (CRC) is the third leading cause of cancer death worldwide. Obesity has been proven to be closely related to colorectal carcinogenesis. This review summarized the potential underlying mechanisms linking obesity to CRC in different aspects, including energy metabolism, inflammation, activities of adipokines and hormones. Furthermore, the potential therapeutic targets of obesity-associated CRC were predicted using network-based target analysis, with total predicted pathways not only containing previously reported pathways, but also putative signaling pathways pending for investigation. In addition, the current conventional therapeutic treatment options, plus the potential use of herbs and natural products in the management of obesity-associated CRC were also discussed. Taken together, the aim of this review article is to provide strong theoretical basis for future drug development, particularly herbs and natural products, in obesity-associated CRC.

Anti-metastatic effects of 1,2,3,4,6-Penta-O-galloyl-ß-D-glucose in colorectal cancer: Regulation of cathepsin B-mediated extracellular matrix dynamics and epithelial-to-mesenchymal transition.

Despite significant advances in the diagnosis and treatment of colorectal cancer (CRC), metastatic colorectal cancer still poses serious threat to CRC patients. The natural gallotannin 1,2,3,4,6-penta-O-galloyl-ß-D-glucose (PGG) has been shown to possess anti-tumor effects on colon cancer cells, but its anti-metastatic effect is yet to be investigated. In this study, the effects of PGG on cell proliferation, colony formation ability, motility, migration were investigated in colon cancer cells using BrdU, colony formation, scratch, and transwell assays, respectively. Western blot assay was used for assessing protein expression. The orthotopic colon tumor-bearing mouse model and human colon cancer metastatic mouse model were employed to evaluate the anti-metastatic effects of PGG. Results showed that PGG exhibited not only anti-proliferative and colony formation inhibitory effects, but also inhibition on cell adhesion, motility, and migration in both HCT116 and colon 26-M01 cells via modulating protein expression of cathepsin B, FAK, cofilin, and epithelial-to-mesenchymal transition related proteins. In addition, PGG (10 or 15 mg/kg, i.p.) could significantly inhibit liver and lung metastasis in colon cancer metastatic mice models. Furthermore, PGG could regulate the populations of T cells, macrophages, and MDSCs, while the levels of IL-2, IL-6, IL-10, IFN-γ, and TNF-α were altered after PGG treatment in metastatic CRC mice. This is the first report of the anti-metastatic effects of PGG by regulating cathepsin B-mediated extracellular matrix dynamics and epithelial-to-mesenchymal transition process in CRC. Our findings suggested that PGG has great potential to be developed as an anti-metastatic agent for metastatic CRC.

Human mast cells induce osteoclastogenesis through cell surface RANKL.

OBJECTIVES: We employed the co-culture of CD34+ stem cell-derived human mast cells (HMC) and human monocyte-derived osteoclast precursors to evaluate if mast cells contribute to the pathogenesis of osteoporosis through regulation of osteoclast proliferation and activation. METHODS: Mature HMC and osteoclast precursors were cultured from monocytes isolated from human buffy coat. The osteoclast precursors were incubated with HMC or receptor activator of nuclear factor kappa-B ligand (RANKL) for a week prior to determination of osteoclast maturation through characterization by their morphology and tartrate resistant acid phosphatase (TRAP) expression. The bone absorption activity was determined by pit formation on osteo-assay plate. RESULTS: Mature osteoclasts were identified following co-culture of osteoclast precursors with HMC for one week in the absence of RANKL and they were capable of bone resorption. These actions of HMC on osteoclasts were not affected by mast cell activators such anti-IgE or substance P but could be reversed by osteoprotegerin (OPG) in the co-culture system suggesting the involvement of RANKL. The expression of RANKL on the cell surface of HMC was confirmed by flow cytometry and the density was not affected by activation of HMC. CONCLUSION: Our study provided direct evidence confirming the initiation of osteoclast proliferation and activation by mast cells through cell surface RANKL suggesting that mast cells may contribute to bone destruction in pathological conditions such as osteoporosis.

Alterations in gut microbiota of esophageal squamous cell carcinoma patients.

BACKGROUND AND AIM: Esophageal squamous cell carcinoma (ESCC) is the most common histological subtype of esophageal cancer worldwide. Patients with ESCC display an altered esophageal microbiota compared with healthy individuals; however, little is known about the gut microbiota in ESCC. METHODS: Here, we characterized the fecal microbiota of 15 ESCC patients and 16 healthy control subjects using 16S rRNA gene sequencing. RESULTS: After controlling for potential confounders, significant alterations in both taxonomic and functional composition of the gut microbiota in ESCC patients were observed. By contrast, alpha diversity of the gut microbiota did not significantly differ between the cases and controls. We observed an enrichment of potentially pro-inflammatory and/or carcinogenic bacteria, such as Butyricimonas, Veillonella, and Streptococcus, and a depletion of butyrate-producing and/or potentially anti-inflammatory bacteria, such as Butyricicoccus, Lachnospiraceae NK4A136 group, and Eubacterium eligens group, in the gut microbiota of ESCC patients. The log-ratios of Streptococcus to Butyricicoccus and Streptococcus to Lachnospiraceae NK4A136 group of the gut microbiota were identified as potential diagnostic biomarkers for ESCC, with an area under the receiver operating characteristic (ROC) curve (AUC) of 0.863 (95% confidence interval: 0.707-1.000) and 0.825 (0.673-0.977), respectively. The diagnostic performance of both microbial biomarkers was validated in another ESCC cohort. CONCLUSIONS: This pilot study has revealed an altered gut microbiota in ESCC patients and has paved the way for large-scale prospective cohort studies to examine the causative relationship between ESCC and gut dysbiosis.

Anti-inflammatory activities of natural cyclopeptide RA-XII in colitis-associated colon cancer mouse model and its effect on gut microbiome.

Colorectal cancer (CRC), the third most common cancer globally, is associated with intestinal inflammation that leads to poor prognosis. RA-XII, a natural cyclopeptide, has previously been reported to possess anti-tumor activities. Here, the anti-inflammatory activities of RA-XII were investigated in colitis-associated colon cancer mice and a co-culture in vitro model, in which colon cancer cells HCT116 and macrophages RAW264.7 were grown together to mimic the inflammatory microenvironment of CRC. Changes of inflammatory-related molecules and protein expressions in cells were evaluated after RA-XII incubation. Besides, azoxymethane and dextran sulfate sodium-induced colitis-associated colon cancer mice were treated with RA-XII for 24 days, inflammatory parameters and gut microbiome alterations were studied. Our results showed that RA-XII reversed the inflammatory responses of RAW264.7 cells induced by LPS and modulated the protein expressions of AKT, STAT3/p-STAT3, P70S6K, NF-κB and GSK3ß and suppressed the expression of LC3A/B in HCT116 cells in co-culture system. RA-XII treatment restored the colitis damage in colon, reduced colon tumors numbers and decreased inflammatory factors (IL-6, IL-10 and TNF-α). The role of RA-XII on regulating gut microbiome was also demonstrated for the first time. In conclusion, our findings provided new scientific evidence for developing RA-XII as a potent anti-inflammatory agent for CRC.

Network pharmacology reveals potential functional components and underlying molecular mechanisms of Andrographis paniculata in esophageal cancer treatment.

Antitumor and antimetastatic effects of the medicinal herb Andrographis paniculata (AP) in esophageal cancer (EC) have been previously reported. In this study, we aimed to uncover the potential functional components and the underlying molecular mechanisms of AP in EC treatment using network pharmacology and experimental validation. Twenty-two potential active AP compounds against EC were revealed, including the antitumor/antiinflammatory compounds panicolin, moslosooflavone, and deoxyandrographiside. Epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3), RAC-alpha serine/threonine-protein kinase (AKT1), prostaglandin-endoperoxide synthase 2 (PTGS2), chemokine (C-X-C motif) ligand 8 (CXCL8), phosphatidylinositol 4,5-bisphosphate 3-kinase subunit alpha (PIK3CA), and toll-like receptor 4 (TLR4) were most highly ranked among the predicted targets of AP in EC treatment and may play important roles in the anti-EC effects of AP. KEGG pathway analysis revealed the enrichment of multiple cancer-related pathways and signaling pathways. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting validation showed that overnight treatment with 850.3 µg/ml of AP water extract significantly reduced the mRNA expressions of EGFR and AKT in human EC-109 cells. The presence of panicolin and moslosooflavone in the AP water extract samples were confirmed using LC-MS against reference standards. This study has comprehensively revealed for the first time the potential functional components of AP in EC and explored the underlying molecular mechanisms. Future studies should characterize the potential pharmacological properties of the other highly ranked yet understudied compounds in AP detected.

A polysaccharide extract from the medicinal plant Maidong inhibits the IKK-NF-κB pathway and IL-1ß-induced islet inflammation and increases insulin secretion.

The herb dwarf lilyturf tuber (Maidong, Ophiopogonis Radix) is widely used in Chinese traditional medicine to manage diabetes and its complications. However, the role of Maidong polysaccharide extract (MPE) in pancreatic ß-cell function is unclear. Here, we investigated whether MPE protects ß-cell function and studied the underlying mechanisms. We treated db/db and high-fat diet (HFD)-induced obese mice with 800 or 400 mg/kg MPE or water for 4 weeks, followed by an oral glucose tolerance test. Pancreas and blood were collected for molecular analyses, and clonal MIN6 ß-cells and primary islets from HFD-induced obese mice and normal chow diet-fed mice were used in additional analyses. In vivo, MPE both increased insulin secretion and reduced blood glucose in the db/db mice but increased only insulin secretion in the HFD-induced obese mice. MPE substantially increased the ß-cell area in both models (3-fold and 2-fold, p < 0.01, for db/db and HFD mice, respectively). We observed reduced nuclear translocation of the p65 subunit of NF-κB in islets of MPE-treated db/db mice, coinciding with enhanced glucose-stimulated insulin secretion (GSIS). In vitro, MPE potentiated GSIS and decreased interleukin 1ß (IL-1ß) secretion in MIN6 ß-cells. Incubation of MIN6 cells with tumor necrosis factor α (TNFα), interferon-γ, and IL-1ß amplified IL-1ß secretion and inhibited GSIS. These effects were partially reversed with MPE or the IκB kinase ß inhibitor PS1145, coinciding with reduced activation of p65 and p-IκB in the NF-κB pathway. We conclude that MPE may have potential for therapeutic development for ß-cell protection.

A review on the relationship of mast cells and macrophages in breast cancer - Can herbs or natural products facilitate their anti-tumor effects?

Breast cancer is an inflammation-related cancer whose tumor microenvironment is largely infiltrated by inflammatory cells. These inflammatory cells including mast cells and macrophages have been elucidated to be vital participants in breast tumor proliferation, survival, invasion and migration. However, the functions of mast cells and macrophages in breast cancer are quite distinct based on recent data. Mast cells exhibit both anti-tumoral and pro-tumoral functions on breast cancer, while high number of tumor-associated macrophages (TAMs) are strongly correlated with poor prognosis and higher risk of distant metastasis in breast cancer patients. Besides, many natural products/extracts have been reported to regulate mast cells and macrophages. In this review, the roles of mast cells and macrophages play in breast cancer are discussed and a summary of those natural products/herbs regulating the functions of mast cells or macrophages is also presented.

A novel binary matrix consisting of graphene oxide and caffeic acid for the analysis of scutellarin and its metabolites in mouse kidney by MALDI imaging.

Although the in vivo metabolic pathways of scutellarin, a traditional Chinese medicine, have been investigated via different liquid chromatography techniques, studies on the distribution and location of scutellarin within organ tissue sections have not been reported. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) can generate in situ spatial distribution profiles for scutellarin and its metabolites in a kidney section. However, the direct detection of a small molecule (m/z < 600) using conventional matrices often results in ion suppression and matrix interferences. In this study, we demonstrated a novel methodology using MALDI-MSI for the in situ spatial localization of scutellarin and its metabolites in kidney tissues by applying a binary matrix of graphene oxide (GO) and caffeic acid (CA). The results indicated that the binary matrix (GO/CA) significantly improved the detection efficiency of scutellarin and its metabolites with relatively high sensitivity, selectivity and reproducibility on tissue sections. This methodology was successfully applied to map scutellarin and its metabolites with MALDI-MSI in mouse kidney tissues. Specifically, scutellarin and scutellarein were found to be located in the cortex and medulla regions of the kidney with relatively high abundance, whereas the remaining metabolites appeared in the cortex with low abundance. We believe that the novel imaging methodology may also be used for the studies of cancerous tissues and inform the development of the future therapies of kidney tumors.

Effectiveness of Scutellaria barbata water extract on inhibiting colon tumor growth and metastasis in tumor-bearing mice.

The plant Scutellaria barbata (SB) is commonly used as herbal medicines for treating cancer. The present pre-clinical study aimed to validate the Chinese Pharmacopoeia (CP) recommended dosages of SB water extract (SBW) in treating colon tumors. The content of chemical marker scutellarin in SBW was quantified using UPLC. Mice bearing human HCT116 xenografts or murine colon26 tumors received oral administration of SBW or scutellarin for 4 weeks. Results showed that SBW (615 and 1,230 mg/kg) and scutellarin (7 mg/kg) treatments significantly reduced human xenograft weights by 28.7, 36.9 and 28.8%, respectively. Lung metastasis area could be ameliorated after SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments by 23.4 and 29.5%, respectively. Expressions of colon cancer metastasis-related proteins E-cadherin, Tspan 8 and CXCR4, as well as Src kinase in tumors were first shown to be regulated by SBW. Furthermore, in murine colon26 tumor-bearing mice, SBW (615 mg/kg) and scutellarin (7 mg/kg) treatments reduced the orthotopic tumor burden by 94.7% and lung metastatic tumor burden by 94.1%, respectively. Our findings provided evidences that SBW (at the mouse equivalent dosages to clinical dosages recommended by CP) could exert anti-tumor and anti-metastatic effects in colon cancer animal models.

Rubinoboletus ballouii polysaccharides exhibited immunostimulatory activities through toll-like receptor-4 via NF-κB pathway.

The biological activities of water-soluble components of edible mushroom Rubinoboletus ballouii (RB) were seldom reported. Polysaccharides of RB (RBP) were prepared and well-characterized using chemical analyses. The immunomodulatory properties of RBP were investigated using human monocyte-derived dendritic cells (moDC) in vitro, and cyclophosphamide (CTX)-induced immunosuppressive mouse model. Results showed that RBP was found to contain 80.6% (w/w) of neutral sugars including D-fucose, D-mannose, D-glucose and D-galactose (1.7:1.4:1.0:1.8), and 12.5% (w/w) of proteins, which composed of glutamine, threonine, serine, etc. RBP could promote the maturation of moDC and increase the secretion of IL-12p40, IL-10, and TNF-α. Furthermore, the stimulation of IL-12p40 production was inhibited by pretreatment with toll-like receptor (TLR)-4 blocker or NF-κB pathway blocker, suggesting that the activation of moDC by RBP was mediated through NF-κB pathway via TLR-4 receptor. On the other hand, in CTX-treated mice, RBP restored the loss of CD34bright CD45dim hematopoietic stem cells and increased IL-2 production in sera and splenocytes culture supernatant, as well as up-regulated the percentage of CD4+ T helper lymphocyte in mice splenocytes. These findings strongly suggested that RBP are the active ingredients of RB responsible for its immunostimulatory actions and deserved to be further investigated as cancer supplements.

Medicinal Plants and Mushrooms with Immunomodulatory and Anticancer Properties-A Review on Hong Kong's Experience.

The immune modulating effects of selected herbs deserve careful studies to gain evidence-based support for their further development. We have been working hard on many items of medicinal herbs to gain insight into their immunomodulatory effects relevant to cancer treatment in particular, while infection control is not excluded. Nine of them have been selected to give the results of our exploration on their biological, particularly immunomodulatory activities. Since Hong Kong people especially favor one medicinal mushroom, viz. Coriolus versicolor, a number of clinical trials using Coriolus for cancer-related studies are included in this review. While immune modulation platforms are being built for relevant studies, a brief account on the research targets and related procedures are given.

Integrated Network Pharmacology Analysis and In Vitro Validation Revealed the Potential Active Components and Underlying Mechanistic Pathways of Herba Patriniae in Colorectal Cancer.

Herba Patriniae (HP) are medicinal plants commonly used in colorectal cancer (CRC) patients. In this study, network pharmacology was used to predict the active components and key signaling pathways of HP in CRC. Patrinia heterophylla, one type of HP, was chosen for validation of the network pharmacology analysis. The phytochemical profile of Patrinia heterophylla water extract (PHW) was determined by UHPLC-MS. MTT, RT-PCR, and Western blot assays were performed to evaluate the bioactivities of PHW in colon cancer cells. Results showed that 15 potentially active components of HP interacted with 28 putative targets of CRC in the compound-target network, of which asperglaucide had the highest degree. Furthermore, the ErbB signaling pathway was identified as the pathway mediated by HP with the most potential against CRC. Both RT-PCR and Western blot results showed that PHW significantly downregulated the mRNA and protein levels of EGFR, PI3K, and AKT in HCT116 cells. Asperglaucide, present in PHW, exhibited an anti-migratory effect in HCT116 cells, suggesting that it could be an active component of PHW in CRC treatment. In conclusion, this study has provided the first scientific evidence to support the use of PHW in CRC and paved the way for further research into the underlying mechanisms of PHW against CRC.

A Natural Flavone Tricin from Grains Can Alleviate Tumor Growth and Lung Metastasis in Colorectal Tumor Mice.

Tricin, a flavone isolated from rice bran, has been shown to be chemopreventive in a colorectal cancer (CRC) mouse model. This study aimed to illustrate the inhibitory activities of tricin in colon cancer cells and in a metastatic CRC mouse model. BALB/c mice injected with mouse Colon26-Luc cells into the rectum wall were treated with tricin (37.5 mg/kg) daily for 18 days. Orthotopic colon tumor growth and metastasis to lungs were assessed by in vivo bioluminescence imaging. Results showed that tricin suppressed Colon-Luc cells motility and downregulated phosphorylated Akt, Erk1/2 and NF-κB expressions of human colon cancer HT-29 cells. While tricin treatment suppressed tumor growth and lung metastasis as well as altered the populations of myeloid-derived suppressor cells and regulatory T cells in spleens. In summary, the tumor microenvironment modulatory and anti-metastatic effects of tricin in colon cancer mouse model were shown for the first time, suggesting the potential development of tricin-containing food supplements for CRC patients.