Antiproliferative Effect of Bioaccessible Fractions of Four Brassicaceae Microgreens on Human Colon Cancer Cells Linked to Their Phytochemical Composition

The antiproliferative effect of the bioaccessible fractions (BFs) of four hydroponic Brassicaceae microgreens (broccoli, kale, mustard and radish) was evaluated on colon cancer Caco-2 cells vs. normal colon CCD18-Co cells after 24 h treatment with BFs diluted 1:10 v/v in cell culture medium. Their bioactivity was compared with the digestion blank, while the colon cancer chemotherapeutic drug 5-fluorouracil was used as a positive control. Cell viability (mitochondrial enzyme activity assay (MTT test) and Trypan blue test) and mechanisms related to antiproliferative activity (cell cycle, apoptosis/necrosis, mitochondrial membrane potential, reactive oxygen species (ROS) production, Ca2+ and glutathione (GSH) intracellular content) were studied. All microgreen BFs increased ROS and decreased GSH, altering the redox status and causing mitochondrial membrane dissipation followed by a general cell cycle arrest in G2/M and apoptotic cell death via a Ca2+-independent mechanism. As a result, the antioxidant bioactive compounds present in these microgreen species reduced the proliferation of tumoral cells (10 to 12.8% -MTT or 20 to 41.9% -Trypan blue), showing lesser effects with broccoli microgreens, in line with their lower ascorbic acid content and total antioxidant capacity. Therefore, the daily intake of microgreens within a balanced diet could be a preventive nutritional strategy to reduce the burden of chronic degenerative diseases such as colon cancer.

Tussilagone Reduces Tumorigenesis by Diminishing Inflammation in Experimental Colitis-Associated Colon Cancer

Background: Tussilagone, a major component of Tussilago farfara L., has anti-angiogenic and anti-inflammatory effects. However, the therapeutic and preventive activity of tussilagone in colitis-associated colon carcinogenesis is unknown. Methods: We intended to investigate the therapeutic effects and the potential mechanism of action underlying the pharmacological activity of tussilagone on colitis-associated colon cancer induced in mice using azoxymethane (AOM)/dextran sulfate sodium (DSS). We injected BALB/c mice with AOM and administered 2% DSS in drinking water. The mice were given tussilagone (2.5 and 5 mg/kg body weight) and colon tissues was collected at 72 days. We used Western blotting, immunohistochemistry and real-time RT-PCR analyses to examine the tumorigenesis and inflammatory status of the colon. Results: Tussilagone administration significantly reduced the formation of colonic tumors. In addition, tussilagone treatment markedly reduced the inflammatory mediators and increased heme oxygease-1 in protein and mRNA levels in colon tissues. Meanwhile, nuclear NF-κB-positive cells were elevated and nuclear Nrf2-positive cells were demised by tussilagone treatment in colon tissues. Tussilagone also reduced cell proliferation, induced apoptosis and decreased the β-catenin expression. Conclusions: Tussilagone administration decreases the inflammation and proliferation induced by AOM/DSS and induced apoptosis in colon tissue. Overall, this study indicates the potential value of tussilagone in suppressing colon tumorigenesis.

Optimization of Catechin and Proanthocyanidin Recovery from Grape Seeds Using Microwave-Assisted Extraction

Grape seed extract (GSE) is a rich source of condensed flavonoid tannins, also called proanthocyanidins (PACs). The high molecular weight of polymeric PAC limits their biological activity due to poor bioavailability. The present study was undertaken to explore the potential applicability of microwave-assisted extraction (MAE) to convert GSE-PAC into monomeric catechins. A central composite design (CCD) was used to optimize the processing conditions for the MAE. The maximum total yield of monomeric catechins (catechin, epicatechin, and epicatechin gallate) and PAC were 8.2 mg/g dry weight (DW) and 56.4 mg catechin equivalence (CE)/g DW, respectively. The optimized MAE condition was 94% ethanol, 170 °C temperature, and a duration of 55 min. Compared to the results for PACs extracted via conventional extraction (Con) (94% ethanol; shaking at 25 °C for 55 min), MAE yielded 3.9-fold more monomeric catechins and 5.5-fold more PACs. The MAE showed higher antioxidant capacity and α-glucosidase inhibitory activity than that of the conventional extract, suggesting the potential use of the MAE products of grape seeds as a functional food ingredient and nutraceutical.

Phytochemicals and Gastrointestinal Cancer: Cellular Mechanisms and Effects to Change Cancer Progression

Gastrointestinal (GI) cancer is a prevailing global health disease with a high incidence rate which varies by region. It is a huge economic burden on health care providers. GI cancer affects different organs in the body such as the gastric organs, colon, esophagus, intestine, and pancreas. Internal and external factors like smoking, obesity, urbanization, genetic mutations, and prevalence of Helicobacter pylori and Hepatitis B and Hepatitis C viral infections could increase the risk of GI cancer. Phytochemicals are non-nutritive bioactive secondary compounds abundantly found in fruits, grains, and vegetables. Consumption of phytochemicals may protect against chronic diseases like cardiovascular disease, neurodegenerative disease, and cancer. Multiple studies have assessed the chemoprotective effect of selected phytochemicals in GI cancer, offering support to their potential towards reducing the pathogenesis of the disease. The aim of this review was to summarize the current knowledge addressing the anti-cancerous effects of selected dietary phytochemicals on GI cancer and their molecular activities on selected mechanisms, i.e., nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), detoxification enzymes, adenosine monophosphate activated protein kinase (AMPK), wingless-related integration site/β-catenin (wingless-related integration site (Wnt) β-catenin, cell apoptosis, phosphoinositide 3-kinases (PI3K)/ protein kinase B AKT/ mammalian target of rapamycin (mTOR), and mitogen-activated protein kinase (MAPK). In this review phytochemicals were classified into four main categories: (i) carotenoids, including lutein, lycopene, and β-carotene; (ii) proanthocyanidins, including quercetin and ellagic acid; (iii) organosulfur compounds, including allicin, allyl propyl disulphide, asparagusic acid, and sulforaphane; and (iv) other phytochemicals including pectin, curcumins, p-coumaric acid and ferulic acid. Overall, phytochemicals improve cancer prognosis through the downregulation of β-catenin phosphorylation, therefore enhancing apoptosis, and upregulation of the AMPK pathway, which supports cellular homeostasis. Nevertheless, more studies are needed to provide a better understanding of the mechanism of cancer treatment using phytochemicals and possible side effects associated with this approach.

Downregulated miR-585-3p promotes cell growth and proliferation in colon cancer by upregulating PSME3

Background

Upregulation of PSME3 and its oncogenic roles have been reported in colon cancer recently. However, the underlying mechanism of PSME3 upregulation remains unknown. Here, we explored the expression of PSME3 and subsequently uncovered its mechanism in colon cancer.

Materials and methods

The expression of PSME3 was analyzed by using online databases, Oncomine and UALCAN. qPCR was carried out to detect the expression of PSME3 in collected colon cancer tissues and cell lines. Moreover, the promoter methylation and the hnRNA level of PSME3 were also analyzed by online database and qPCR, respectively. The candidate miRNAs targeting PSME3 were predicted by Starbase 3.0 and validated by luciferase reporter system. CCK-8, plate colon formation, and Edu incorporation were applied to study the functions of miRNA in colon cancer. The expression of miRNA and its correlation with PSME3 were detected in colon cancer tissues.

Results

Oncomine and UALCAN data indicate PSME3 is obviously upregulated in colon cancer tissue samples which is further confirmed in collected colon cancer tissues and cells by qPCR. No significant difference in methylation status promoter of PSME3 was observed between colon and colon cancer tissues. The hnRNA level of PSME3 was comparable between colon epithelial cell and colon cancer cells. miR-585-3p is predicted to directly target PSME3 and is validated by luciferase reporter assay. Then, miR-585-3p downregulation is confirmed and miR-585-3p restoration can suppress cell growth and proliferation by inhibiting PSME3 in colon cancer indicating by CCK-8, plate colon formation, and Edu incorporation. Moreover, negative correlation in expression between miR-585-3p and PSME3 was observed in our collected tissues samples.

Conclusion

We reveal for the first time that miR-585-3p downregulation accounts for the overexpression of PSME3 in colon cancer. Moreover, miR-585-3p, serving as a tumor suppressor, can inhibit cell growth and proliferation in colon cancer by targeting PSME3.

American Ginseng (Panax quinquefolium L.) as a Source of Bioactive Phytochemicals with Pro-Health Properties

Panax quinquefolium L. (American Ginseng, AG) is an herb characteristic for regions of North America and Asia. Due to its beneficial properties it has been extensively investigated for decades. Nowadays, it is one of the most commonly applied medical herbs worldwide. Active compounds of AG are ginsenosides, saponins of the glycosides group that are abundant in roots, leaves, stem, and fruits of the plant. Ginsenosides are suggested to be primarily responsible for health-beneficial effects of AG. AG acts on the nervous system; it was reported to improve the cognitive function in a mouse model of Alzheimer's disease, display anxiolytic activity, and neuroprotective effects against neuronal damage resulting from ischemic stroke in animals, demonstrate anxiolytic activity, and induce neuroprotective effects against neuronal damage in ischemic stroke in animals. Administration of AG leads to inhibition of hypertrophy in heart failure by regulation of reactive oxygen species (ROS) in mice as well as depletion of cardiac contractile function in rats. It also has an anti-diabetic and anti-obesity potential as it increases insulin sensitivity and inhibits formation of adipose tissue. AG displays anti-cancer effect by induction of apoptosis of cancer cells and reducing local inflammation. It exerts antimicrobial effects against several pathogenic strains of bacteria. Therefore, AG presents a high potential to induce beneficial health effects in humans and should be further explored to formulate precise nutritional recommendations, as well as to assess its value in prevention and therapy of some disorders, including cancer.

Reduction of Preneoplastic Lesions Induced by 1,2-Dimethylhydrazine in Rat Colon by Maslinic Acid, a Pentacyclic Triterpene from Olea europaea L

Maslinic acid triggers compelling antiproliferative and pro-apoptotic effects in different human cancer cell lines. Hence, the chemopreventive activity was investigated on early stages of carcinogenesis induced by 1,2-dimethylhydrazine (DMH) which is a model that mimics human sporadic colorectal cancer. Male Sprague-Dawley rats were orally administered either maslinic acid at 5, 10 or 25 mg/kg dissolved in (2-hydroxypropyl)-β-cyclodextrin 20% (w/v) or the solvent for 49 days. After one week of treatment, animals received three weekly intraperitoneal injections of DMH at the dose of 20 mg/kg. Maslinic acid reduced the preneoplastic biomarkers, aberrant crypt foci (ACF) and mucin-depleted foci (MDF), already at 5 mg/kg in a 15% and 27%, respectively. The decline was significant at 25 mg/kg with decreases of 33% and 51%, respectively. Correlation analysis showed a significant association between the concentrations of maslinic acid found in the colon and the reduction of ACF (r = 0.999, p = 0.019) and MDF (r = 0.997, p = 0.049). The present findings demonstrate that maslinic acid induced an inhibition of the initiation stages of carcinogenesis. The assessment of this pentacyclic triterpene at the colon sheds light for designing diets with foods rich in maslinic acid to exert a chemopreventive activity in colorectal cancer.

Furowanin A-induced autophagy alleviates apoptosis and promotes cell cycle arrest via inactivation STAT3/Mcl-1 axis in colorectal cancer

Aim Furowanin A (Fur A) is a flavonoid isolated from Millettia pachycarpa Benth. Studies show its potent anti-neoplastic effects against leukemia cells. The aim of the present study was to determine the potential therapeutic effect of Fur A against colorectal cancer (CRC), and elucidate the underlying mechanism.

MATERIAL AND METHODS

Cell Counting Kit-8 (CCK-8) assay was used to determine cell, and TUNEL and Annexin-V/PI staining was used to detect apoptosis and the cell cycle distribution. The expression levels of specific proteins in the CRC cells were analyzed by Western blotting. A xenograft model was also established to evaluate the therapeutic effect of Fur A in vivo.

KEY FINDINGS

Fur A suppressed proliferation, blocked cell cycle progression, induced apoptosis and promoted autophagy in CRC cells. Interestingly, Fur A-induced autophagy functioned not only as a survival mechanism against apoptosis but also intensified the cell cycle arrest in CRC cells. In addition, Fur A mediated its effects via the inactivation of the STAT3/Mcl-1 axis.

SIGNIFICANCE

Fur A is a promising drug candidate for the treatment and prevention of CRC.

Novel Docosahexaenoic Acid Ester of Phloridzin Inhibits Proliferation and Triggers Apoptosis in an In Vitro Model of Skin Cancer

Skin cancer is among the most common cancer types accompanied by rapidly increasing incidence rates, thus making the development of more efficient therapeutic approaches a necessity. Recent studies have revealed the potential role of decosahexaenoic acid ester of phloridzin (PZDHA) in suppressing proliferation of liver, breast, and blood cancer cell lines. In the present study, we investigated the cytotoxic potential of PZDHA in an in vitro model of skin cancer consisting of melanoma (A375), epidermoid carcinoma (A431), and non-tumorigenic (HaCaT) cell lines. Decosahexaenoic acid ester of phloridzin led to increased cytotoxicity in all cell lines as revealed by cell viability assays. However, growth inhibition and induction of both apoptosis and necrosis was more evident in melanoma (A375) and epidermoid carcinoma (A431) cells, whereas non-tumorigenic keratinocytes (HaCaT) appeared to be more resistant as detected by flow cytometry. More specifically, PZDHA-induced cell cycle growth arrest at the G2/M phase in A375 and A431 cells in contrast to HaCaT cells, which were growth arrested at the G0/G1 phase. Elevated intracellular generation of reactive oxygen species ROS was detected in all cell lines. Overall, our findings support the potential of PZDHA as a novel therapeutic means against human skin cancer.

Flavonoids and Colorectal Cancer Prevention

Colorectal cancer (CRC) is the third most common cancer, but despite advances in treatment, it remains the second most common cause of cancer-related mortality. Prevention may, therefore, be a key strategy in reducing colorectal cancer deaths. Given reports of an inverse association between fruit and vegetable consumption with colorectal cancer risk, there has been significant interest in understanding the metabolism and bioactivity of flavonoids, which are highly abundant in fruits and vegetables and account for their pigmentation. In this review, we discuss host and microbiota-mediated metabolism of flavonoids and the potential mechanisms by which flavonoids can exert protective effects against colon tumorigenesis, including regulation of signaling pathways involved in apoptosis, cellular proliferation, and inflammation and modulation of the gut microbiome.

Cryptotanshinone inhibits the growth and invasion of colon cancer by suppressing inflammation and tumor angiogenesis through modulating MMP/TIMP system, PI3K/Akt/mTOR signaling and HIF-1α nuclear translocation

The aim of this study was to evaluate the pharmacological effects of CPT on CT26 colon cancer cells in vivo and in vitro, and to reveal the potential mechanism. CPT suppressed the proliferation and growth of CT26 colon cancer in vitro and in vivo. CPT inhibited the invasion of CT26 cells in vitro, and decreased the protein expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 but increased those of tissue inhibitor of metallopeptidase-1 (TIMP-1) and TIMP-2 in vitro and in vivo. It also inhibited tumor cell-induced angiogenesis of endothelial cells in vitro and rat aortic ring angiogenesis ex vivo, and possibly by suppressing angiogenesis-associated factors. CPT suppressed the expressions of inflammatory factors in vivo and in vitro. Mechanism studies showed that CPT inhibited the PI3K/AKT/mTOR signaling pathway, as evidenced by decreased expressions of phospho-PI3K (p-PI3K), p-Akt and p-mTOR. Moreover, CPT significantly suppressed the nuclear expression but increased the cytosolic expression of hypoxia inducible factor-1α (HIF-1α). Collectively, CPT inhibited the growth, invasion, inflammation and angiogenesis in CT26 colon cancer, and at least partly, by regulating the PI3K/Akt/mTOR signaling and the nuclear translocation of HIF-1α.