Human Colon Cancer Caco-2 Cells Research Articles

Phytochemical examination of Cistus laurifolius Extract and its Impact on Cytotoxicity, Apoptosis and Oxidative Stress in Colorectal and Breast Cancer Cell Lines

IntroductionColon and breast cancer are the most common types of cancer worldwide. This study investigatesd the anticancer properties of Cistus laurifolius L. leaf extract on breast cancer (MCF-7) and human colon cancer (Caco-2) cell lines. MethodsThe research involved meticulous collection, drying and processing of C. laurifolius leaves to extract bioactive compounds, subsequently analyzed for phenolic content using advanced LC-MS/MS technology. Cell viability of the extract on MCF-7 and Caco-2 cells was demonstrated by MTT test. Levels of critical apoptotic markers (Bad, Bax/Bcl-2, Bax/Bcl-xl, Caspase-9) and Total Antioxidant Capacity (TAC) and Total Oxidant Capacity (TOC), which affect the antioxidant system, were evaluated by the ELISA method. Identification of phenolic compounds, including quercetin and rutin, through target prediction analysis enriches our understanding of bioactive molecules. ResultsThe results of the study showed that C. laurifolius extract inhibited cell proliferation time and dose-dependent on Caco-2 and MCF-7 cells (P<0.05). TAC, Bax/Bcl-2 and Bax/Bcl-xl ratios in MCF-7 and Caco-2 cells increased in a dose-dependent manner compared to the control group. In MCF-7 cells, TAC (p<0.05; p<0.01), Bax/Bcl-2 (p<0.001; p<0.0001) and Bax-Bcl-xl (p<0.01) ratios increased at 24 hours compared to the control group. In Caco-2 cells, TAC (p<0.001), Bax/Bcl-2 ratios increased at 48 hours (p<0.05), while Bax-Bcl-xl ratios decreased (p<0.01; p<0.001) compared to the control group. ConclusionC. laurifolius leaf extracts emerge as a promising anticancer candidate, hindering cell proliferation and inducing apoptosis in colon and breast cancer cells. The classification of bioactive molecules may facilitate further clinical therapeutic interventions targeting colon and breast cancer.

Synergistic effects of cetuximab and agomelatine on gene expression in colon cancer cells

Colorectal cancer (CRC) continues to be one of the most prevalent malignancies worldwide, necessitating innovative therapeutic interventions. This study aims to elucidate the combinatorial effects of the chemotherapeutic agent Cetuximab (CTX) and the antidepressant agomelatine on the expression levels of key genes in the CACO-2 human colon cancer cell line. The PI3K/Akt/mTOR signaling pathway, integral to various physiological processes, was primarily investigated, revealing significant modulations upon drug treatments. Notably, 24-hour treatments with 0.3 µg/ml and 0.3 µg/ml+50 µg/ml evidenced suppressed proliferation of PIK3CA, EGFR, and AKT genes, while sparing mTOR. Conversely, 48-hour applications of 50 µg/ml and 0.3 µg/ml+50 µg/ml exhibited suppression in mTOR, PIK3CA, and EGFR, leaving AKT unaffected. These findings underscore the potential of combined CTX and agomelatine therapy in CRC, offering insights into gene-specific modulations that may pave the way for enhanced therapeutic outcomes.

The m6A methyltransferase METTL3 modifies Kcnk6 promoting on inflammation associated carcinogenesis is essential for colon homeostasis and defense system through histone lactylation dependent YTHDF2 binding

Inflammation induces tumor formation and plays a crucial role in tumor progression and prognosis. KCNK6, by regulating K(+) efflux to reduce NLRP3 Inflammasome-induced lung injury, relaxes the aorta. This study aims to elucidate the effects and biological mechanism of KCNK6 in inflammation-associated carcinogenesis, which may be essential for colon homeostasis and the defense system. To induce colitis, mice were given 3.0% Dextran Sodium Sulfate (DSS) in their drinking water for 7 days. The Azoxymethane (AOM) +DSS method was used to induce colon cancer in the mice model. Bone marrow-derived macrophages (BMDM) from Kcnk6-/- mice, AW264.7 cells, and human colon cancer HCT116 and Caco2 cells were used as in vitro models. The loss of Kcnk6 prevented spontaneous colitis and restored mucosal integrity and homeostatic molecules. Additionally, the loss of Kcnk6 reduced the severity of AOM/DSS-induced carcinogenesis. Kcnk6 promoted cell viability and proliferation in HCT-116 or Caco-2 cells. The loss of Kcnk6 inhibited the levels of inflammatory factors in BMDM cells. Kcnk6 accelerated potassium channel activity, inducing NLRP3 inflammasome activation. METTL3-mediated m6A modification increased Kcnk6 stability in a YTHDF2-dependent manner. Histone lactylation activated the transcription of YTHDF2/Kcnk6. Our study revealed the important role of Kcnk6 in inflammation-associated carcinogenesis progression. The m6A methyltransferase METTL3 and histone lactylation increased Kcnk6 stability in a YTHDF2-dependent manner, providing a potential strategy for inflammation-associated carcinogenesis or colorectal cancer therapy.

Novel pH-sensitive gellan gum-ε-polylysine hydrogel microspheres for sulforaphene delivery.

This study aimed to improve the stability and utilization of sulforaphene (SFE) and to enhance the intestinal stability and pH-sensitive release of SFE in the gastrointestinal tract. To achieve this objective, calcium chloride (CaCl2) was used as a crosslinking agent to fabricate novel SFE-loaded gellan gum (GG)-ε-polylysine (ε-PL) pH-sensitive hydrogel microspheres by using the ionic crosslinking technique. The molecular docking results of GG, ε-PL, and SFE were good and occurred in the natural state. The loading efficiency (LE) of all samples was above 70%. According to the structural characterization results, GG and ε-PL successfully embedded SFE in a three-dimensional network structure through electrostatic interaction. The swelling characteristics and in vitro release results revealed that the microspheres were pH-sensitive, and SFE was mainly retained inside the hydrogel microsphere in the stomach, and subsequently released in the intestine. The result of cytotoxicity assay showed that the hydrogel microspheres were non-toxic and had an inhibitory effect on human colon cancer Caco-2 cells. Thus, the hydrogel microspheres could improve SFE stability and utilization and achieve the intestinal targeted delivery of SFE. © 2024 Society of Chemical Industry.

Combining network pharmacology and experimental verification to study the anti-colon cancer effect and mechanism of sulforaphene.

Sulforaphene is a derivative of glucosinolate and a potential bioactive substance used for treating colon cancer. This study aimed to evaluate the potential inhibitory effect and mechanisms of sulforaphene in human colon cancer Caco-2 cells. Network pharmacology, molecular docking, and experimental verification were performed to elucidate potential sulforaphene mechanisms in the treatment of this condition. Network pharmacology predicted 27 intersection target genes between sulforaphene and colon cancer cell inhibition. Key sulforaphene targets associated with colon cancer cell inhibition were identified as EGFR, MAPK14, MCL1, GSK3B, PARP1, PTPRC, NOS2, CTSS, TLR9, and CTSK. Gene ontology functional enrichment analysis revealed that the above genes were primarily related to the positive regulation of peptidase activity, cytokine production in the inflammatory response, and the cell receptor signaling pathway. Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that sulforaphene mainly inhibited the proliferation of cancer cells by affecting apoptosis as well as the signaling pathways of PD-1, Toll-like receptor, T cell receptor, and P13k-Akt. Molecular docking results further confirmed that CTSS, GSK3B, and NOS2 were significantly up-regulated and had good binding affinity with sulforaphene. In vitro experiments also indicated that sulforaphene had a significant inhibitory effect on human colon cancer Caco-2 cells. This paper revealed the pharmacodynamic mechanism of sulforaphene in the treatment of colon cancer for the first time. It provides scientific insight into the development of sulforaphene as a medicinal resource. © 2024 Society of Chemical Industry.

Mangiferin, A Naturally Occurring Glucosylxanthone, Induces Apoptosis in Caco-2 Cells In Vitro and Exerts Protective Effects on Acetic Acid-Induced Ulcerative Colitis in Mice through the Regulation of NLRP3.

Inflammatory bowel diseases (IBD), an inflammatory disease, include Crohn's disease and ulcerative colitis. Dysregulated autoimmune response to gut dysbiosis is mainly involved in the pathogenesis of IBD and is triggered by various inciting environmental factors. With its rising prevalence in every continent, IBD has evolved into a global disease, which is on the rise, affecting people of all ages. There is a growing incidence of IBD in the elderly population, as evidenced by epidemiological data. IBD is characterized by an inflammatory process that requires a lifelong treatment. The main challenge in IBD management is the adverse side effects associated with almost all of the currently available drugs. Hence, there is a search for drugs with more efficacy and fewer side effects. Natural products with great structural diversity and ease of modification chemically are being explored, as they were shown to control IBD by safely suppressing pro-inflammatory pathways. The present study aims at understanding the role of mangiferin, a COX-2 inhibitor isolated from tubers of Pueraria tuberosa in the treatment of IBD and colon cancer, in vitro on the Caco-2 human colon cancer cell line and in vivo in the acetic acid-induced IBD mouse model. In the acetic acid-induced colitis model, it prevented the decrease in length of the colon, mucosal erosion, and cellular infiltration in a dose-dependent manner. The expression levels of various pro-inflammatory markers like COX-2, IL1β, TNF-α, INF-γ, IL-6, NLRP3, and caspase-1 were downregulated in an acetic acid-induced mouse model on treatment with mangiferin in a dose dependent manner. Mangiferin also showed anticancer effects on Caco-2 cells by increasing the expression of Fas ligand, Fas receptor, FADD, caspase-8, and caspase-3 proteins, whereas Bid and Bcl-2 proteins showed decreased expression. These data suggest that mangiferin, an inhibitor of COX, induces apoptosis in colon cancer cells in vitro and protects mice from acetic acid-induced colitis in vivo.

Cetuximab Enhances the Efficacy of MRTX1133, a Novel KRASG12D Inhibitor, in Colorectal Cancer Treatment.

Kirsten Rat Sarcoma viral oncogene homolog (KRAS) has remained undruggable for decades. KRAS has predominantly been used to evaluate the applicability of anti-Epidermal Growth Factor Receptor (EGFR) antibody drugs. However, various KRAS inhibitors have recently emerged. Unfortunately, KRAS inhibitors have not been effective against colorectal cancer. Therefore, this study aimed to determine the effects of MRTX1133, a novel KRASG12D inhibitor, in combination with an anti-EGFR antibody, cetuximab, on signal transduction and cell proliferation. The KRASG12D-mutated LS513 and KRAS wild-type CACO-2 human colon cancer cell lines were utilized. The KRASG12D mutation was stably transduced into the CACO-2 cells using a retrovirus. We evaluated the effects of the drugs using the CCK-8 assay and assessed the activity of proteins related to the MAPK pathway using western blotting. We demonstrated that the administration of MRTX1133, a novel KRASG12D inhibitor, to KRASG12D-mutated colorectal cancer cells led to feedback activation of the ERK pathway via EGFR activation, inducing drug resistance. Intriguingly, when MRTX1133 was used in combination with cetuximab, KRASG12D-mutant colorectal cancer growth was effectively inhibited, both in vitro and in vivo. The combination of MRTX1133 and cetuximab serves as a potential and promising therapeutic approach for colorectal cancer with KRASG12D mutation. KRASG12D is a frequent genetic mutation not only in colorectal cancer, but also in pancreatic and lung cancer, and the results of this study open new avenues for potential treatment of many cancer patients.

Resveratrol enhances paclitaxel-induced apoptosis through oxidative DNA damage in Caco-2 human colon cancer cells

Resveratrol enhances paclitaxel-induced apoptosis through oxidative DNA damage in Caco-2 human colon cancer cells

Development of an efficient method for separation and purification of cordycepin from liquid fermentation of Cordyceps militaris and analysis of cordycepin antitumor activity

Cordycepin (3 ′-deoxyadenosine) is the main active component of Cordyceps militaris, which is a chemical marker for quality detection of Cordyceps militaris and has important medicinal development value. Existing methods for obtaining cordycepin are complex and costly. In this study, an economical and simple method for separation and purification of cordycepin from Cordyceps militaris fermentation liquid through physical crystallization was explored. First, lyophilized powdered fermentation liquid (LPFL) and pure methanol (1 g/100 mL, w/v) were mixed, and then repeatedly dissolved and crystallized until the precipitation was white. Purified product was obtained by freeze-drying the precipitate. The substance was determined to be cordycepin by high performance liquid chromatography, mass spectrometry and infrared spectroscopy, and the purity was 94.26%. Compared with the existing methods, this method is simple and low cost. In addition, the functional activity of cordycepin was determined by in vitro test. The results exhibited that cordycepin caused death and morphological changes in human colon cancer Caco-2 cells, and significantly inhibited the proliferation of Caco-2 cells, with a half-maximal inhibitory concentration (IC50) of 107.2 μg/mL. Cordycepin could induce early apoptosis of Caco-2 and caused cell cycle arrest in the G2 phase. Caco-2 cell apoptosis and cell cycle arrest showed dose dependence to cordycepin over a certain range. These results improved cordycepin purification method, provided insights into the mechanism of cordycepin in cancer inhibition, and would provide important reference for further development and clinical application of cordycepin.

Akkermansia muciniphila plays a neuroprotective role in HMC3 cells through the 'gut-brain' axis.

Aims: We investigated the neuroprotective effects of Akkermansia muciniphila through the 'gut-brain' axis. Methods: Human colon cancer (Caco-2) cells treated with A. muciniphila metabolites were used to create theconditioned medium from Caco-2 cells treated with A. muciniphila metabolites (AC medium)medium, then treated human microglial clone 3 (HMC3) cells to simulate the gut-brainaxis in vitro. Bioinformatics analyses were performed to investigate the molecular mechanisms by which the AC medium affected HMC3 cells. Results: The secretion of inflammatory cytokines IL-6 (0.37±0.80-fold) and IL-17A (0.05±0.18-fold) by HMC3 cells was inhibited by the AC medium. Differentially expressed genes were mainly enriched in immune-related signaling pathways, such as the cAMP and TGF-β signaling pathways. Conclusion: A. muciniphila might be a source of therapeutic approaches to alleviate microglia-mediated neuroinflammatory diseases.

Effect of combination treatment of protocatechuic acid with 5-fluorouracil and oxaliplatin on colon cancer Caco-2 cell line

Among the most common antitumor drugs used in the treatment of colon cancer are 5-fluorouracil and oxaliplatin (5-FU and OXA). However, both these drugs have many side effects, and hence there is a need for new treatment\approach to reduce the side effects aas well as drug concentration. In this context, here, we investigated the effect of addition of protocatechuic acid (PCA) onto either monotherapies or combination therapies of 5-FU and OXA on the human colon cancer (Caco-2) cell line. In addition, we did evaluate the synergistic effect of PCA with 5-FU and OXA. Further, we determined the suppressive effects of different doses of PCA alone or in combination with 5-FU/OXA on cell proliferation after 24 and 48 hours. We identified a suppressive effect of PCA on cell viability at 48 h starting from the dose of 50 µM Matrix metalloproteinase-2 (MMP-2) and MMP-9 gene expression levels and apoptotic effects showed significant increases and decreases depending on the dose and time applied in the experimental groups. The highest synergistic activity was seen at 2:1 concentration of 5-FU+ PCA. Our findings indicate the presence of the cytotoxic and apoptotic effects of PCA in Caco-2 cells at 48 h, increasing with a dose- and time-dependent manner.

Antiproliferative effect of Lactobacillus casei and Lactobacillus fermentum cell-free supernatants on colonic cancer cell line

Cell-free supernatants of two probiotics namely Lactobacillus casei and Lactobacillus fermentum were assessed for their antiproliferative and antitumor activity on human colon cancer CaCo2 and normal NCM425 cell lines. MTT 3-(4,5- Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay was used to detect cytotoxic activity and cell viability. Our results indicated that both supernatants exhibited cytotoxic activities and their impact was in a dose-dependent manner. The results also showed that the supernatants were less toxic to normal cells. Lactobacillus casei cell-free supernatant (LcCFS) was more cytotoxic on cancer cells than Lactobacillus fermentum cell-free supernatant (LfCFS) at higher concentrations. However, no significant differences were observed between the impact of LcCFS and LfCFS on the NCM425 cell line. In conclusion, cell-free supernatants of Lactobacillus casei and Lactobacillus fermentum could be good candidates for cancer treatment and control.

Co-Treatment of Caco-2 Cells with Doxorubicin and Gold Nanoparticles Produced from Cyclopia intermedia Extracts or Mangiferin Enhances Drug Effects.

Mangiferin (MGF) is a natural and valuable polyphenol found in significant levels in many plant species, including Cyclopia intermedia (C. intermedia). In a previous study, we synthesized gold nanoparticles (AuNPs) using MGF and a water extract of C. intermedia and reported that these AuNPs have very low cytotoxicity toward a human colon cancer (Caco-2) cell line. Although the study also showed that these biogenic AuNPs in combination with doxorubic (DOX) significantly augmented the cytotoxic effects of DOX in Caco-2 cells, the mechanism of the enhanced effect was not fully understood, and it was also not known if other cell lines would be sensitive to this co-treatment. In the present study, we examined the cytotoxicity of the co-treatment in Caski, HeLa, HT-29, KMST-6 and MDA-321 cell lines. Additionally, we investigated the mechanistic effects of this co-treatment in Caco-2 cells using several assays, including the adenosine triphosphate (ATP), the oxidative stress, the mitochondrial depolarization, the colony formation, the APOPercentage and the DNA fragmentation assays. We also assessed the intracellular uptake of the biogenic AuNPs. The study showed that the biogenic AuNPs were effectively taken up by the cancer cells, which, in turn, may have enhanced the sensitivity of Caco-2 cells to DOX. Moreover, the combination of the biogenic AuNPs and DOX caused a rapid depletion of ATP levels, increased mitochondrial depolarization, induced apoptosis, reduced the production of reactive oxygen species (ROS) and inhibited the long-term survival of Caco-2 cells. Although the study provided some insight into the mechanism of cytotoxicity induced by the co-treatment, further mechanistic and molecular studies are required to fully elucidate the enhanced anticancer effect of the co-treatment.

Alginate/κ-carrageenan oral microcapsules loaded with Agaricus bisporus polysaccharides MH751906 for natural killer cells mediated colon cancer immunotherapy.

The current study explores the effect of the extracted novel Mushroom polysaccharides and its formulation onto Alginate (Alg.)/kappa carrageenan microcapsules to exert immunotherapeutic effect upon activating gut resident natural killer cells (NK) against colon cancer. The extracted polysaccharides of Agaricus bisporus MH751906 was microcapsulated in Alg/κ-carrageenan microcapsules as an oral delivery system for colon cancer. The microcapsule is characterized by SEM, FTIR, Raman and TGA; and showed a superior acidic stability, controlled release, and thermal stability at high temperature with higher hydrogel swelling rate in colon-mimicking pH. Upon activation of human NK cells with microcapsules (ANK cells), a significant increase in CD16+CD56+ NK cell populations were recorded. These activated NK cells showed 74.09% cytotoxic effects against human colon cancer Caco-2 cells where majority of cancer cell populations arrested at G0/G1 phase leading to apoptosis. The apoptotic molecular mechanism induced by ANK cells on Caco-2 treated cells is through down regulations of both BCL2 and TGF surviving genes and up regulation in IkappaB-α gene expression. Therefore, this novel polysaccharides-alginate/κ-carrageenan microcapsules can be used as an oral targeted delivery system for colon cancer immunotherapy.

An Integrated Proteomics and Bioinformatics Analysis of the Anticancer Properties of RT2 Antimicrobial Peptide on Human Colon Cancer (Caco-2) Cells.

New selective, efficacious chemotherapy agents are in demand as traditional drugs display side effects and face growing resistance upon continued administration. To this end, bioactive molecules such as peptides are attracting interest. RT2 is a cationic peptide that was used as an antimicrobial but is being repurposed for targeting cancer. In this work, we investigate the mechanism by which this peptide targets Caco-2 human colon cancer cells, one of the most prevalent and metastatic cancers. Combining label-free proteomics with bioinformatics data, our data explore over 1000 proteins to identify 133 proteins that are downregulated and 79 proteins that are upregulated upon treatment with RT2. These changes occur in a dose-dependent manner and suggest the former group are related to anticancer cell proliferation; the latter group is closely related to apoptosis levels. The mRNA levels of several genes (FGF8, PAPSS2, CDK12, LDHA, PRKCSH, CSE1L, STARD13, TLE3, and OGDHL) were quantified using RT-qPCR and were found to be in agreement with proteomic results. Collectively, the global change in Caco-2 cell protein abundance suggests that RT2 triggers multiple mechanisms, including cell proliferation reduction, apoptosis activation, and alteration of cancerous cell metabolism.

Improved solubility of lornoxicam by inclusion into SBA-15: Comparison of loading methods

An increasing proportion of new medicinal substances are poorly soluble in water. Adsorption on mesoporous silicas increases their bioavailability when administered orally. Loading method determines adsorption either on the surface in crystalline state or inside the mesopores in amorphus form. The aim of this study was to compare two methods (adsorption equilibrium and solvent evaporation) of lornoxicam adsorption on SBA-15 and APTES-modified SBA-15 in terms of drug adsorption site. Additionally, we investigated the drug release profiles at different pH and cytotoxicity of the analysed mesoporous materials. The materials were characterized by a number of physicochemical techniques including X-ray diffraction, nitrogen adsorption/desorption techniques, differential scanning calorimetry, thermogravimetric analysis, scanning and transmission electron microscopy, infrared spectroscopy and 1H NMR. Lornoxicam was loaded on the studied materials and released in the media (HCl pH 1.2, phosphate buffers pH 6.8 and 7.4). The cytotoxicity assays of APTES-modified SBA-15 were performed on CaCo-2 human colon cancer cell line. We proved that adsorption equilibrium method is a more advantageous method of loading. It ensures drug adsorption in an amorphous state inside the mesopores. The solvent evaporation method, despite a greater amount of loaded drug, results in drug adsorption in a crystalline state on the silica surface. In drug release studies a greater amount of lornoxicam is released from modified materials compared to crystalline lornoxicam. Cytotoxicity study proved the safety of APTES-modified silica. We concluded that APTES-modified SBA-15 is applicable as an effective and non-toxic carrier for the poorly soluble drug lornoxicam. The adsorption equilibrium method should be the preferred loading method. It enables the adsorption of sparingly soluble substances inside the mesoproes and enhances bioavailability of oral pharmaceutical forms.

Effects of some anti-diabetic herbal extracts on the insulin-degrading enzyme in human colon cancer Caco-2 cell line.

Objective:Type 2 diabetes mellitus (T2DM) is a condition characterized by insufficient insulin production or insulin resistance. The insulin-degrading enzyme (IDE) is responsible for degrading insulin and is a potential drug target for T2DM treatment. Numerous activities have been proposed for plant extracts, but research on the effects of plant extracts on IDE expression and activity is riddled with drawbacks.Materials and Methods:We investigated the effect of Phaseolus vulgaris, Allium cepa, Portulaca oleracea, Cinnamomum verum, and Citrullus colocynthis extracts on the expression and activity of IDE in the Caco-2 cell line.Results: Findings of RT-PCR showed that IDE gene expression was reduced following treatment with P. vulgaris, C. colocynthis, and C. verum extracts. The results of IDE activity with fluorogenic peptide substrate V also indicated that P. vulgaris, C. colocynthis, and P. oleracea extracts reduced IDE activity in a significant and dose-dependent manner.Conclusion:The hydroalcoholic extracts studied, except for A. cepa, can prevent insulin degradation by reducing the expression and activity of the IDE enzyme. This new insight into the effects of herbal medicines on IDE activity can help future studies.

Antioxidant and pro-apoptosis activities of coffee husk (Coffea arabica) anthocyanins

The commercial use of coffee (Coffea arabica) husks, one of the major solid residues obtained during the dry processing of coffee, has previously been considered unprofitable. However, coffee husks are an excellent source of stable anthocyanins that have antioxidative, anti-inflammatory, and cardioprotective properties. The present work identified two anthocyanins, cyanidin-3-glucoside and cyanidin-3-rutinoside, from coffee husks by high-performance liquid chromatography and liquid chromatography-mass spectrometry. The antioxidant capabilities were tested by quenching free radical scavenge assay, reducing power, and ORAC assay at 50, 100, 150, 200 mg/L of coffee husk anthocyanins (CHAs). Moreover, the effects of different concentrations of CHAs on superoxide dismutase (SOD) and lactate acid dehydrogenase (LDH), and the concentration of malondialdehyde (MDA) in human umbilical vein endothelial cells exposed to hydrogen peroxide were also evaluated. Human colon cancer (Caco-2) cell apoptosis induced by CHAs was examined by flow cytometry. Based on the results, CHAs showed strong dose-dependent antioxidant activities, and could increase SOD activity, and suppress indicators for oxidative injuries such as MDA and LDH. Furthermore, the proportion of apoptotic Caco-2 cells ranged from 4.12 to 41.3% in response to treatment with different concentrations of CHAs. These results suggest that CHAs exhibit antioxidant and pro-apoptosis activities.

Enhancement of Apo2L/TRAIL signaling pathway receptors by theactivation of Klotho genewithCRISPR/Cas9 in Caco-2 colon cancer cells.

Human Klotho gene has many known functions such as anti-aging and anti-tumor, and decreased expression of this gene causes malignant formations in most types of cancer, including colon cancer. Interacting with TRAIL death receptors (DR4 and DR5) induces an apoptotic effect in cancer treatments by reducing the proliferation of cancer cells. The present study aimed to investigate downstream effect of overexpression of Klotho gene, which is known to have an antitumor effect on resistant human colon cancer cells, by examining its action on TRAIL death and decoy (DcR1 and DcR2) receptors for the first time. For this purpose, upregulation of human Klotho gene was achieved with CRISPR/Cas9-mediated system in resistant human colon cancer Caco-2 cells. To determine the effect of upregulation of Klotho gene on cancer cells evaluations with flow cytometry, WST-8, qRT-PCR, ELISA, and immunohistochemical analysis were performed. Then, Klotho gene was knocked out and its apoptotic effect was tested to find out whether it is due to overexpression of Klotho gene or not. Our results indicate that overexpression of Klotho gene in Caco-2 cells via CRISPR/Cas9-sensitized TRAIL death receptor DR4 suppresses the proliferation of cells by leading to apoptosis. Thus, this study conducted on apoptosis-resistant colon cancer cells may bring new insights about the role of Klotho gene in colon cancer.

Ketogenesis alleviates TNFα-induced apoptosis and inflammatory responses in intestinal cells

The disturbance of strictly regulated self-regeneration in mammalian intestinal epithelium is associated with various intestinal disorders, particularly inflammatory bowel diseases (IBDs). TNFα, which plays a critical role in the pathogenesis of IBDs, has been reported to inhibit production of ketone bodies such as β-hydroxybutyrate (βHB). However, the role of ketogenesis in the TNFα-mediated pathological process is not entirely known. Here, we showed the regulation and role of HMGCS2, the rate-limiting enzyme of ketogenesis, in TNFα-induced apoptotic and inflammatory responses in intestinal epithelial cells. Treatment with TNFα dose-dependently decreased protein and mRNA expression of HMGCS2 and its product, βHB production in human colon cancer cell lines HT29 and Caco2 cells and mouse small intestinal organoids. Moreover, the repressed level of HMGCS2 protein was found in intestinal epithelium of IBD patients with Crohn's disease and ulcerative colitis as compared with normal tissues. Furthermore, knockdown of HMGCS2 enhanced and in contrast, HMGCS2 overexpression attenuated, the TNFα-induced apoptosis and expression of pro-inflammatory chemokines (CXCL1-3) in HT29, Caco2 cells and DLD1 cells, respectively. Treatment with βHB or rosiglitazone, an agonist of PPARγ, which increases ketogenesis, attenuated TNFα-induced apoptosis in the intestinal epithelial cells. Finally, HMGCS2 knockdown enhanced TNFα-induced reactive oxygen species (ROS) generation. In addition, hydrogen peroxide, the major ROS contributing to intestine injury, decreased HMGCS2 expression and βHB production in the intestinal cells and mouse organoids. Our findings demonstrate that increased ketogenesis attenuates TNFα-induced apoptosis and inflammation in intestinal cells, suggesting a protective role for ketogenesis in TNFα-induced intestinal pathologies.