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Colorectal cancer (CRC) is the fourth most common cause of malignant tumor death. The development of novel, more effective drugs is desperately needed to treat CRC. Zingiber officinale is believed to possess anticancer properties due to its flavonoids and phenols. Using Soxhlet (SOXT) and maceration (MACR) techniques, the present study aimed to evaluate the amounts of quercetin, gallic acid, rutin, naringin, and caffeic acid in ginger capsules of Z. officinale. High‐performance liquid chromatography (HPLC)/ultraviolet was used for separation and quantitation. In vitro toxicity evaluation of ginger capsules on the CRC cell line HT‐29 was also conducted to assess the anticancer activity of the supplement. The cell line HT‐29 (HTB‐38) colorectal adenocarcinoma was utilized for the antiproliferative effect of 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide. Ginger herbal supplement extract at dosages of 200 and 100 μg had strong cytotoxic effects (IC50 < 50 μg/mL) on HT‐29 CRC cells via MACR. This extract is comparable to the SOXT extract, which has an IC50 of less than 50 μg/mL. The anticancer effect of ginger herbal supplement formulations against CRC lines was investigated, and the results obtained from both the MACR and SOXT extraction procedures were noteworthy. The quercetin content was the highest of all the extracts according to the HPLC data. [ABSTRACT FROM AUTHOR]

The ice plant (Mesembryanthemum crystallinum L.) is a halophyte that could become an alternative crop because of its interest as a functional food and its adaptation to high‐saline soils. In this work, leaves from wild ice plants were compared with their cultivated counterparts in a soilless system at different salinities and light exposures for assessing growth parameters, moisture, fatty acid profiles, total carotenoids, phenolic compounds, vitamin C, antioxidant activity, and antiproliferative activity against the HT‐29 colorectal cancer cell line. Moisture ranged between 876 and 955 g kg−1, and wild plants contained higher proportions of α‐linolenic acid (58.7%–60.7% of total fatty acids) than cultivated ones (20.4%–36.6%). Vitamin C ranged between 819 and 1143 mg kg−1 fresh leaves. Higher salinity led to a larger production of carotenoids, whereas plant mass, total phenolic content, and antioxidant activity increased in plants grown using L8 NS1 and L8 AP67 lamps in comparison with white‐light ones. Phenolic profiles were assessed by LC coupled to a hybrid mass spectrometer Q‐Orbitrap. Total phenolic acid content was 3–4‐fold higher than that of flavonoids, and sinapic, p‐coumaric, gallic, 4‐hydroxybenzoic, and 2‐hydroxy‐4‐methoxybenzoic acids, as well as gallocatechin, occurred in all samples. Hydroalcoholic extracts of ice plant leaves showed dose‐ and time‐dependent antiproliferative activity against the HT‐29 human colorectal cancer cell line, and GI50 was between 920 and 977 μg mL−1 of plant extract. This work contributes to improving knowledge about the growth parameters, phytochemical profiles, and biological activities of wild and cultivated ice plants. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the third most malignant cancer occurring around the world. Effective prevention and treatment have been increasingly the focus of global attention. Long‐term diet of fermented dairy inhibits proliferation of colon cancer cell, which is considered that not only live lactic acid bacteria but also the secreted exopolysaccharides exert the function. In this scenario, this study aimed to investigate the mechanism of growth inhibition on HT‐29 cells induced in vitro by exopolysaccharides isolated from Lactobacillus paracasei subsp. paracasei M5L (M5‐EPSs). HT‐29 cells which were treated by a set of concentrations of M5‐EPSs have been investigated of cell viability, characteristic changes, cell cycle distribution, and redox system. The results demonstrated that M5‐EPSs treatments induced HT‐29 cell apoptosis and resulted in upregulation of ROS levels and downregulation of antioxidant enzyme activities, leading to an imbalance in the oxidation system in HT‐29 cells. In response to M5‐EPSs, endogenous ER stress (ERS) markers, including GRP78, ATF4, and CHOP, were transcriptionally altered so that activating the ERS in HT‐29 cells. After NAC treatment, the oxidative stress was inhibited, and the expression of GRP78 and CHOP was significantly decreased, indicating that oxidative stress can significantly affect the ERS pathway. Furthermore, it suggested that the occurrence of apoptosis was associated with Bcl‐2 gene family. In conclusion, this study demonstrated that M5‐EPSs can induce HT‐29 cells apoptosis by destroying the redox system through activation of the ERS signaling pathway. [ABSTRACT FROM AUTHOR]

Cerium oxide nanoparticles (CeO2 NPs) are among the important nanoparticles that are extensively utilized in cosmetics, automotive industries, ultraviolet (UV) filtration, gas sensors, and pharmaceutical products. In this study, CeO2 NPs were synthesized using an aqueous extract of Ziziphus jujube fruit. The synthesized nanoparticles were characterized using UV‐visible spectroscopy, powder X‐ray diffraction, Fourier transform infrared spectroscopy, energy‐dispersive spectroscopy, field energy scanning electron microscopy, and Raman methods. The results indicated that the size of synthesized nanoparticles is between 18 and 25 nm, and they have a spherical shape. UV absorbance of the synthesized nanoparticles was measured through spectrophotometric method in the range of 290 to 320 nm. The cytotoxic activity of synthesized CeO2 NPs against colon (HT‐29) cancer cell line was surveyed through 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. The results showed that synthesized nanoparticles are nontoxic on HT‐29 cells under 400 μg/mL concentrations after 24 hours of treatment time periods. The increase in treatment time cases increases cytotoxic activity of synthesized nanoparticles. Sun protection factor of CeO2 NPs, as a criterion for amount of sunlight radiation protection, was determined by applying Mansur equation. The results demonstrated that synthesized CeO2 NPs have excellent UV protection and sunscreen physical absorption properties. [ABSTRACT FROM AUTHOR]

A number of scientific studies have revealed that Lactobacillus strains have beneficial bioactivities in the gastrointestinal tract. In this study, the production of intracellular reactive oxygen species (ROS) and the amounts of intracellular calcium, protein kinase C activity, cytochrome c, Bid, Bcl-2, Bax and the apoptosis-mediated proteins [caspase-8, caspase-3 and poly ADP ribose polymerase (PARP)] were evaluated to understand the induction of programmed cell death in HT-29 cells by Lactobacillus plantarum L67. The results obtained from this study indicated that the relative intensities of the apoptotic-related factors (intracellular ROS and intracellular calcium) and of apoptotic signals (Bax and t-Bid) increased with increasing concentrations of the membrane proteins isolated from heat-killed L. plantarum L67, whereas the relative intensities of cytochrome c, Bcl-2, caspase-8, caspase-3 and PARP decreased. This study determines whether proteins (12 and 15 kDa) isolated from heat-killed L. plantarum L67 induce programmed cell death in HT-29 cells. Proteins isolated from L. plantarum L67 can stimulate the apoptotic signals and then consequently induce programmed cell death in HT-29 cells. The results in this study suggest that the proteins isolated from L. plantarum L67 could be used as an antitumoural agent in probiotics and as a component of supplements or health foods. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this study, a new neurotensin (NT) analog was labeled with 99mTc via HYNIC chelator and tricine as coligand and investigated further. An NT (7-13) analog was prepared, and labeling with 99mTc was performed. The internalization rate and biodistribution of radiopeptide were studied in HT-29 cells and nude mice bearing tumor, respectively. Radiolabeling with 99mTc was performed at high specific activities (54 MBq/nmol) with an acceptable labeling yield (>95%). In vitro cell line studies showed a specific internalization uptake up to 13.23 ± 0.45% during 4 h which was blocked in the presence of excess cold peptide to 0.83 ± 0.15%. In biodistribution studies, uptake was observed in NT receptor-positive organs so that after 1 h the uptakes in mouse intestine and tumor were 1.23 ± 0.16% ID/g and 1.12 ± 0.11% ID/g, respectively. In animals co-injected with excess cold peptide, reduction uptake in tumor and intestines were 73% (1.10% vs. 0.29% ID/g at 4 h) and 61% (1.22% vs. 0.47% ID/g at 4 h) respectively. Predominant renal excretion pathway with a highest accumulation of activity in bladder was observed for this radiopeptide. This radiolabeled peptide could be a candidate for detection of NT positive tumors. [ABSTRACT FROM AUTHOR]

Background and Purpose: Fluoroquinolones are potent anti-microbial agents with multiple effects on host cells and tissues. Previous studies have highlighted their pro-apoptotic effect on human cancer cells and an immunoregulatory role in animal models of inflammatory bowel disease. We examined the effect of ciprofloxacin on proliferation, cell cycle and apoptosis of HT-29 cells, a human colonic epithelial cell line sensitive to transforming growth factor (TGF)-beta1-mediated growth inhibition and its role in TGF-beta1 production. We also examined the effect of ciprofloxacin on proliferation of HT-29 cells in combination with 5-fluorouracil (5-FU), a well-established pro-apoptotic agent.Experimental Approach: Using subconfluent cultures of HT-29 and Caco-2 cells, we studied the effect of ciprofloxacin, TGF-beta1 and 5-FU on proliferation, apoptosis, necrosis and cell cycle. The effect of ciprofloxacin on TGF-beta1 mRNA expression and production was studied in RNA extracts and cell culture supernatants respectively, using confluent cultures.Key Results: Ciprofloxacin decreased proliferation of HT-29 cells in a concentration- and time-dependent manner. This was mediated by accumulation of HT-29 cells into the S-phase but without any effect on apoptosis or necrosis. Additionally, ciprofloxacin enhanced the antiproliferative effect of 5-FU. Interestingly, ciprofloxacin was found to up-regulate TGF-beta1 production by HT-29 cells and its anti-proliferative effect was abolished when TGF-beta1 was blocked. Confirming this mechanism further, ciprofloxacin had no effect on Caco-2, a human colonic epithelial cell line that lacks functional TGF-beta1 receptors.Conclusions and Implications: We demonstrate a novel anti-proliferative and immunoregulatory effect of ciprofloxacin on human intestinal epithelial cells mediated via TGF-beta1. [ABSTRACT FROM AUTHOR]

Abstract: The present study was to see whether echinomycin-induced apoptosis would be NF-κB-dependent and if so, whether echinomycin would activate or inhibit NF-κB as well as resultant chemokine IL-8 expression. In HT-29 cells echinomycin activated NF-κB in time-dependent manner. EMSA in the presence of antibodies specific for p50 and p65 subunits indicated that echinomycin-induces the translocation of p50–p65 heterodimeric subunits of NF-κB. Levels of IκB were detected at initial echinomycin treatment and thereafter decreased, faintly seen after a 6h treatment. In contrast p-IκB levels were clearly detected throughout 6–24h of echinomycin treatment, albeit initially fainted. To clarify the role of NF-κB on IL-8 expression in echinomycin-mediated apoptosis of HT-29 cells, ELISA plus RT-PCR clearly showed that IL-8 production is inducible by echinomycin treatment. Using a specific inhibitor, IL-8 regulation at echinomycin treatment in HT-29 cells occurred via both caspase-3 and NF-κB-dependent signal pathway. To confirm whether two different pathways (NF-κB and caspase) would be coupled, only NF-κB inhibitor (PDTC) and caspase-3 specific inhibitor (Z-DEVD-FMK) together significantly attenuated echinomycin-initiated apoptosis of HT-29 cells, pretreatment of HT-29 cells with PDTC rarely affected echinomycin-induced caspase-3 activation. So echinomycin-induced apoptosis in HT-29 cells occurs via NF-κB activation independent of caspase-3 activation modulating the resultant-linked key chemokine IL-8 expression and echinomycin-induced apoptosis is NF-κB-dependant and directly related to NF-κB activation, consequently regulating IL-8 expression. [Copyright &y& Elsevier]

Casein phosphopeptides (CPPs) form aggregated complexes with calcium phosphate and induce Ca2+ influx into HT-29 cells that have been shown to be differentiated in culture. The relationship between the aggregation of CPPs assessed by laser light scattering and their biological effect was studied using the CPPs β-CN(1–25)4P and αs1-CN(59–79)5P, the commercial mixture CPP DMV, the ‘cluster sequence’ pentapeptide, typical of CPPs, and dephosphorylated β-CN(1–25)4P, [β-CN(1–25)0P]. The biological effect was found to be: (a) maximal with β-CN(1–25)4P and null with the ‘cluster sequence’; (b) independent of the presence of inorganic phosphate; and (c) maximal at 4 mmol·L−1 Ca2+. The aggregation of CPP had the following features: (a) rapid occurrence; (b) maximal aggregation by β-CN(1–25)4P with aggregates of 60 nm hydrodynamic radius; (c) need for the concomitant presence of Ca2+ and CPP for optimal aggregation; (d) lower aggregation in Ca2+-free Krebs/Ringer/Hepes; (e) formation of bigger aggregates (150 nm radius) with β-CN(1–25)0P. With both β-CN(1–25)4P and CPP DMV, the maximum biological activity and degree of aggregation were reached at 4 mmol·L−1 Ca2+. [ABSTRACT FROM AUTHOR]

Resveratrol has been reported to possess therapeutic effects for various cancers including colon cancers. In this article, the molecular basis of resveratrol with emphasis on its ability to control intracellular signaling cascades of adenosine monophosphate (AMP)-activated protein kinase (AMPK) responsible for inducing apoptosis in drug-resistant cancer cells was investigated. Recently, the evolutionarily conserved serine/threonine kinase, AMPK, emerges as a possible target molecule of cancer control. We have investigated the effects of resveratrol on apoptosis in relation to AMPK in HT-29 cells shown chemoresistant to a cancer chemotherapeutic drug, etoposide. Resveratrol exhibited a variety of molecular events in etoposide-based combination therapy in HT-29 colon cancer cells including the AMPK activation, inhibition of cell growth, induction of apoptosis, and reactive oxygen species (ROS) generation. The involvement of AMPK signaling cascade in resveratrol-based cancer therapy was clearly shown by comparing the conditions of AMPK activated states and inactivated states. We have identified ROS as an upstream regulator of AMPK. Further investigation warrants to elucidate the mechanism by which resveratrol generates ROS and AMPK activation. [ABSTRACT FROM AUTHOR]

Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is activated during ATP-depleting metabolic states, such as hypoxia, heat shock, oxidative stress, and exercise. As a highly conserved heterotrimeric kinase that functions as a major metabolic switch to maintain energy homeostasis, AMPK has been shown to exert as an intrinsic regulator of mammalian cell cycle. Moreover, AMPK cascade has emerged as an important pathway implicated in cancer control. In this article, we have investigated the effects of capsaicin on apoptosis in relation to AMPK activation in colon cancer cell. Capsaicin-induced apoptosis was revealed by the presence of nucleobodies in the capsaicin-treated HT-29 colon cancer cells. Concomitantly, the activation of AMPK and the increased expression of the inactive form of acetyl-CoA carboxylase (ACC) were detected in capsaicin-treated colon cancer cells. We showed that both capsaicin and 5′-aminoimidazole-4-carboxamide-1-β-D-ribonucleoside (AICAR), an AMPK activator possess the AMPK- activating capacity as well as apoptosis-inducing properties. Evidence of the association between AMPK activation and the increased apoptosis in HT-29 colon cancer cells by capsaicin treatment, and further findings of the correlation of the activated AMPK and the elevated apoptosis by cotreatment of AICAR and capsaicin support AMPK as an important component of apoptosis, as well as a possible target of cancer control. [ABSTRACT FROM AUTHOR]

Some data suggest that cholecystokinin (CCK) receptor agonists stimulate the growth of colon cancer. Melatonin, an endogenous indoleamine with strong antioxidant properties, displays antiproliferative and proapoptotic properties both in vivo or in vitro in several types of tumors. We used HT-29 human colon cancer cells, expressing CCK receptors, to test the antiproliferative effects of several antagonists of CCK-A and/or CCK-B and their possible synergism with melatonin. HT-29 cells were cultured in RPMI 1640 medium supplemented with fetal bovine serum at 37°C. Cell proliferation was assessed by the incorporation of [3H]-thymidine into DNA. Annexin V-FITC plus propidium iodine were used for flow cytometry apoptosis/necrosis evaluation. The following drugs were tested: gastrin (CCK-B agonist); CCK-8s (CCK-A agonist); proglumide (CCK-A plus CCK-B antagonist); lorglumide (CCK-A antagonist); PD 135,158 (CCK-B antagonist and weak CCK-A agonist); devazepide or L 364,718 (CCK-A antagonist); L 365,260 (CCK-B antagonist), and melatonin. The results shown a lack of effects of gastrin on HT-29 cell proliferation, whereas CCK-8s induced proliferation at high doses. The order of the antiproliferative effect of the other drugs was devazepide > lorglumide > proglumide. These drugs produce cell death mainly inducing apoptosis. Melatonin showed strong antiproliferative effect at millimolar concentrations, and it induced apoptotic cell death. Melatonin generally enhanced the antiproliferative effects of devazepide, lorglumide and proglumide and increased the proglumide-induced apoptosis. These results suggest that melatonin and CCK-A antagonists are useful for controlling human colon cancer cell growth in culture and in combined therapy significantly increases their efficiency. [ABSTRACT FROM AUTHOR]

The effects of apoptosis induction on glucose and phospholipid metabolite levels in cancer were studied using human colon adenocarcinoma cells (HT-29). Apoptosis was induced by co-incubation with 200 U/ml tumor necrosis factor (TNF)-α for 4, 8 or 15 h, after sensitization with 500 U/ml interferon (IFN)-γ for 7 h. Perchloric acid extracts were analyzed by 1H and 31P nuclear magnetic resonance (NMR) spectroscopy. Significantly increased lactate and NTP (all nucleoside 5’-triphosphates) signals were detected 4 h after apoptosis-inducing IFN-γ/TNF-α treatment, but not in cells which were TNF-α-treated without IFN-γ preincubation. Simultaneous lactate and NTP changes, if confirmed in vivo, may serve as early, non-invasive markers of treatment response in some tumors. [Copyright &y& Elsevier]

To clarify the regulatory mechanism of the production of various inflammatory mediators by intestinal epithelial cells, the effect of bile acids (tauroursodeoxycholate, TUDC; taurochenodeoxycholate, TCDC; and taurocholate, TC) on the cytokine-induced production of interleukin (IL)-8 in a human colon epithelial cell line (HT-29) was examined. HT-29 cells were incubated for 24 h in a culture medium containing tumour necrosis factor α (TNFα; 1 ng/mL) and/or interleukin (IL)-1β (1 ng/mL) in the presence or absence of bile acids. The IL-8 concentration in the medium was measured by an enzyme-linked immunosorbent assay. The binding assay of TNFα was performed using [125I]-TNFα (100 pmol/L). Interleukin-8 production during incubation with TNFα was markedly reduced in the presence of 0.5 and 1 mmol/L TUDC, 0.5 and 1 mmol/L TCDC and 0.5 and 1 mmol/L TC, by 56, 85, 86, 91, 37 and 70%, respectively. The IL-8 production during incubation with IL-1β was not significantly reduced in the presence of these bile acids. The specific binding of TNFα to cells was inhibited 33, 47, and 14% by 1 mmol/L TUDC, TCDC and TC, respectively. These findings suggest that bile acids inhibit TNFα-induced IL-8 production by the colonic cells. The suppression may be partly due to inhibition of TNFα binding to the cells by bile acids. [ABSTRACT FROM AUTHOR]

The aim of the study was to ascertain whether the exposure to ethanol of human colon carcinoma CaCo-2 and HT-29 cell lines affects the differentiation process. As an index of enterocytic differentiation, the expression of sucrase, alkaline phosphatase, α2,6-sialyltransferase toward the N-acetyllactosaminic sequence, and β1,4- N-acetylgalactosaminyltransferase (β1,4GalNAc-transferase) was examined. The latter enzyme is responsible for the biosynthesis of Sd* carbohydrate histo-blood antigen, which mainly occurs in human colonic cells; its expression in CaCo-2 cells depends strictly on the enterocytic differentiation. The addition of ethanol in the culture medium resulted in a significant increment of sucrase and α2,6-sialyltransferase activities in both cell lines, as well as theβ1,4GalNAc-transferase activity in CaCo-2 cells and alkaline phosphatase activity in HT-29 cells. The increment was dose-dependent in the range between 50 and 200 mm ethanol and evident after 2 days of exposure in both cell systems. These results support the notion that, as occurs for cell lines of different origin, the ethanol in vitro positively affects the differentiation of intestinal cells, namely along the enterocytic lineage. The putative mechanism by which ethanol interferes with the maturation process of colonic cells is discussed. [ABSTRACT FROM AUTHOR]

Recently it was demonstrated that the metabolism of both glycoproteins and sphingo(glyco)lipids is dependent upon the state of enterocytic differentiation of HT-29 cells. Furthermore, it was shown that undifferentiated HT-29 cells display an important autophagic sequestration, controlled by a heterotrimeric G1, protein. In order to correlate the metabolism of sphingo(glyco)lipids with the extent of autophagic sequestration, we have incubated undifferentiated and differentiated HT-29 cells with tritium-labelled GM1 ganglioside and sphingosine in the absence and presence of pertussis toxin (an inhibitor of autophagic sequestration) or asparagine (an inhibitor of autophagic vacuole maturation). In addition, undifferentiated HT-29 cells transfected with a cDNA encoding the GU1 protein (cells expressing an amplified autophagic pathway) were labelled with both GMI and sphingosine. The result show that the catabolism of sphingo(glyco)lipids is dramatically enhanced in parallel with the increase of the autophagic pathway while at the same time their biosynthesis is reduced. The inhibition of autophagy in both undifferentiated cells and α1-overexpressing cells restores sphingo(glyco)lipid metabolism, as normally expressed in differentiated cells, as well as in other mammalian cell types. We conclude that autophagy plays an important role in governing the metabolic fate of sphingo(glyco)lipids in HT-29 cells. Since autophagy regulates the N-linked glycoprotein metabolism in this cell line, our results corroborate the idea that glycolipid and glycoprotein metabolisms are controlled by similar mechanisms. [ABSTRACT FROM AUTHOR]