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Objective:To establish a colon cancer cell line which overexpressing LINC01018 stably and study its biological characteristics.Methods:The expression of LINC01018 in HCoEpiC and HT-29 cells were detected by real time fluorescence quantitative polymerase chain reaction (qRT-PCR). HT-29 cells were infected with LINC01018 overexpression lentivirus to screen and establish HT-29 cell lines which overexpressing LINC01018 stably. The effect of LINC01018 on the proliferation, invasion and migration of HT-29 cells were detected by cell counting kit-8 (CCK-8) assay and Transwell assay separately. The expression of CDK6 and matrix metalloproteinase-2 (MMP-2) in HT-29 cells was detected by Western blot.Results:The expression of LINC01018 in HT-29 cells was significantly lower than that in the human colonic epithelial cells (HCoEpiC). HT-29-L18 cell lines which overexpressing LINC01018 stably was screened successfully. Overexpression of LINC01018 significantly inhibited the cell proliferation, invasion and migration, and reduced the protein expression of CDK6 and MMP-2 in HT-29 cells.Conclusions:The expression of LINC01018 was decreased abnormally in colon cancer cells. Up-regulation of LINC01018 expression can inhibit the proliferation, invasion and migration of colon cancer cells, which may be related to CDK6 and MMP-2.
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AIM: To study the inhibitory effect and mechanism of Jolkinolide B (JB) on the proliferation and metastasis of colon cancer HT-29 cells. METHODS: HT-29 cells were treated with different concentrations of JB, the cell proliferation rate was detected by MTT method, the cell clone formation rate was detected by plate cloning experiment, the cell cycle change was detected by flow cytometry, the cell migration ability was analyzed by wound healing assay, the cell invasion ability was studied by Transwell assay, E-cadherin, N-cadherin, vimentin, Snail1, Snail2, matrix metalloproteinase (MMP)-2 and MMP-9 protein expression levels were detected by immunofluorescence and Western blotting, and p-PI3K, PI3K, p-Akt, Akt, NF-κB P65and p-NF-κB P65 protein expression levels were detected by Western blotting. HT-29 cells were treated with 100 μg/L IGF-1 and 100 μg/L IGF-1+20 μmol/L JB, respectively. The expression of PI3K/Akt/NF-κB pathway related proteins was detected by Western blotting. RESULTS: JB inhibited the proliferation of HT-29 cells in a concentration-dependent manner, with an IC
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RESUMEN Objetivos: Determinar el efecto citotóxico y genotóxico in vitro del extracto crudo y etanólico del rizoma de Curcuma longa L. Materiales y métodos: El efecto citotóxico fue evaluado utilizando líneas celulares DU-145, HT-29, 3T3 BALB/c. Se hallaron los porcentajes de crecimiento en 48 horas y se determinó la concentración inhibitoria 50 (CI50). El efecto genotóxico en el ADN genómico humano se determinó mediante el método Tomasevich. Resultados: El extracto crudo produjo una CI50 de 12,98 ± 0,21 μg/mL para la línea celular tumoral HT-29, que es inferior a DU-145 con una CI50 de 36,77 ± 9,12 μg/mL; el extracto etanólico presentó una CI50 de 13,24 ± 0,77 y 20,54 ± 2,58 µg/mL para ambas líneas celulares, respectivamente; el compuesto estándar curcumina presentó una CI50 de 3,96 ± 0,60 y 13,94 ± 2,79 μg/mL, respectivamente. El extracto crudo a concentraciones de 50 y 100 mg/mL fragmentó entre el 40% a 95% de ADN genómico humano; mientras que, a 200 mg/mL, la fragmentación fue mayor al 95%. El extracto etanólico a todas las concentraciones no fragmentó el ADN. La curcumina a 200 mg/mL fragmentó menos del 5% de ADN genómico humano. Conclusiones: Los extractos crudo y etanólico de Curcuma longa L. demuestran efecto citotóxico in vitro diferencial para la línea celular tumoral humana DU-145 y HT29 semejante al compuesto estándar curcumina. El extracto crudo de Curcuma longa L. presenta una potente actividad genotóxica in vitro frente al ADN genómico humano, esta actividad está ausente en el extracto etanólico.
ABSTRACT Objectives: To determine the in vitro cytotoxic and genotoxic effect of the crude and ethanolic extract from the Curcuma longa L. rhizome. Materials and methods: The cytotoxic effect was evaluated using DU-145, HT-29, 3T3 BALB/c cell lines. The growth percentages in 48 hours; and the half maximal inhibitory concentration (IC50) were determined. The genotoxic effect on human genomic DNA was determined using the Tomasevich method. Results: Crude extract produced an IC50 of 12.98 ± 0.21 μg/mL for the HT-29 tumor cell line, which is lower than the value obtained for DU-145, with an IC50 of 36.77 ± 9.12 μg/mL. The ethanolic extract presented an IC50 of 13.24 ± 0.77 and 20.54 ± 2.58 μg/mL for both cell lines, respectively; the curcumin standard compound presented an IC50 of 3.96 ± 0.60 and 13.94 ± 2.79 μg/mL, respectively. Crude extract concentrations of 50 and 100 mg/mL fragmented between 40% to 95% of human genomic DNA; while at 200 mg/mL, fragmentation was greater than 95%. The ethanolic extract at all concentrations did not fragment the DNA. Curcumin at 200 mg/mL fragmented less than 5% of human genomic DNA. Conclusions: The crude and ethanolic extracts of Curcuma longa L. demonstrate different in vitro cytotoxic effects for the human tumor cell lines DU-145 and HT-29; similar to the standard curcumin compound. The crude extract of Curcuma longa L. shows a potent genotoxic in vitro activity against human genomic DNA; this type of effect is not produced by the ethanolic extract.
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In Vitro Techniques , Curcuma , Rhizome , Cell Line, Tumor , Complex Mixtures , Cell Line , HT29 Cells , Inhibitory Concentration 50 , BALB 3T3 CellsABSTRACT
OBJECTIVE：To investigate the inhibitory effects of total alkaloids of Gelsemium elegans （TAG） on the proliferation and angiogenesis of human colon cancer cells. METHODS ：Human colon cancer cell line HT- 29 and HUVEC were cultured in vitro . After the intervention of low- ，medium-，high-dose TAG （40，80，120 μg/mL），the morphology of the two cells was observed by fluorescence inversion microscope. The survival rate of HT- 29 cells and HUVEC was detected by CCK- 8 assay. Flow cytometry was used to detect HT- 29 cell cycle. The migration rate ，invasion rate and tube number of HUVEC were observed by scratching test ，Transwell invasion experiment and tube formation experiment. RESULTS ：Compared with blank group ，HT-29 cells and HUVEC were decreased to different extents in TAG groups ；dead cells were observed ，and the survival rate of both decreased significantly （P＜0.05 or P＜0.01）. The proportion of HT- 29 cells at G 2/M phase in TAG groups as well as those at G 0/G1 phase in medium-dose group were increased significantly ；the proportion of HT- 29 cells at S phase in TAG groups as well as those at G 0/G1 phase in high-dose group were decreased significantly （P＜0.05 or P＜0.01）. Survival rate ，migration rate and invasion rate of HUVEC were decreased significantly in TAG groups ，and tube number was also decreased significantly at each time point during 4-24 h（P＜0.01）. CONCLUSIONS ：TAG have inhibitory effect on the proliferation of human colon cancer HT- 29 cells and HUVEC，can change HT- 29 cell cycle ，inhibit the migration ，invasion and tube formation of HUVEC.
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OBJECTIVE：To investigate the effects and its mechanism of pseudostrychnine on the apoptosis of human colon can - cer HT- 29 cells. METHODS ：Human colon cancer HT- 29 cells were randomly divided into blank group ，pseudostrychnine low-dose，medium-dose and high-dose groups （125，250，500 μmol/L）. They were cultured with culture medium without medicine or relevant concentration of pseudostrychnine for 48 h. The cell apoptosis and mitochondrial transmembrane potential were detected by flow cytometry. Western blotting assay was employed to detect the protein expression of P 53，Caspase-3，Caspase-9，DNA re - pair enzyme from rabbit （c-PARP）and Bcl- 2. RESULTS ：Compared with blank group ，apoptotic rate of cells was increased signifi - cantly in pseudostrychnine low-dose ，medium-dose and high-dose groups ，while mitochondrial transmembrane potential was de - creased significantly （P＜0.01），in concentration-dependent manner. The protein expression levels of P 53，Caspase-3，Caspase-9 and c-PARP were increased in pseudostrychnine medium-dose and high-dose groups ，compared with blank group ；while those of Bcl-2 were decreased significantly in pseudostrychnine low-dose ，medium-dose and high-dose groups （P＜0.05 or P＜0.01）. CON - CLUSIONS：Pseudostrychnine may change mitochondrial membrane potential by up-regulating the protein expression of P 53 and down-regulating the protein expression of Bcl- 2，and activate the expression of Caspase- 3，c-PARP and Caspase- 9，so as to acti - vate endogenous mitochondrial pathway and promote the apoptosis of HT- 29 cells.
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Objective To study the inhibitory effects of Chinese yam combined with tegafu on colon cancer HT-29 cells in vivo and in vitro.Methods The changes of cell morphology were observed by the method of adopting 2×2 factorial designs,after HT-29 colon cancer cells were treated with physiological saline containing dimethyl sulfoxide(blank control), tegafur(36 mg/L)and Chinese yam(125 mg/L).MTT method was used to detect the proliferation of tumor cells,and flow cytometry was used to detect the expression of tumor stem cells(CD133+cells).The nude mouse model of colon cancer HT-29 cells was established. The treatment was given in the above method, and the tumor inhibition rate was calculated. The VEGF positive rate of the tumor was detected by immunohistochemistry. Results The inhibited proliferation of colon cancer HT-29 cells was significantly higher in the synergistic group than that in Chinese yam group and tegafur group,and the inhibitory rates were higher in the three treatment groups than that of blank control group.The proportion of CD133+cells was significantly lower in HT-29 cells in the synergistic group compared with that of the Chinese yam group and the tegafur group,and which was lower in these three groups than that of the blank control group.After the treatment in three treatment groups,the tumor quality and VEGF positive rate were significantly lower than those of the blank control group,and which was lower in the tegafur+Chinese yam group than that of Chinese yam group and the tegafur group. Conclusion Chinese yam combined with tegafu can inhibit the proliferation of colon cancer HT-29 cells and their stem cells.
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<p><b>OBJECTIVE</b>A subcutaneous transplantation tumor model of human HT-29 cells was established in nude mice to study the anticarcinogenic activities and apoptosis-regulatory mechanistic effect of aqueous extract of fermented barley with Lactobacillus plantarum dy-1 (LFBE).</p><p><b>METHODS</b>HT-29 cells were transplanted via subcutaneous injection of 1 × 107cells into the right flank of each nude mouse. Then, nude mice were treated for 30 days with LFBE (high-dose 2 g·kg-1·d-1; low-dose 1 g·kg-1·d-1) and for 7 days with 5-fluorouracil (5-FU, 25 g·kg-1·d-1) by gavage and intraperitoneal injection, respectively.</p><p><b>RESULTS</b>Tumor volume and weight decreased significantly in both groups of nude mice treated with LFBE. In addition, the cell apoptosis rate of the LFBE group was significantly higher than that of the control group and 5-FU groups as measured by the TUNEL assay. Moreover, the real-time fluorescent quantitative PCR and Western blot methods further confirmed these apoptosis-enhancing and growth-inhibiting effects. The involvement of LFBE in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, caspase-3, and cyclinD1.</p><p><b>CONCLUSION</b>The results showed that LFBE could induce subcutaneous transplantation tumor apoptosis in nude mice and could be used as a natural nutrient supplement or chemopreventive agent in the treatment of human colon cancer.</p>
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Animals , Female , Humans , Apoptosis , Caspase 3 , Metabolism , Cell Proliferation , Cyclin D1 , Metabolism , Fermentation , HT29 Cells , Hordeum , Chemistry , Lactobacillus plantarum , Mice, Nude , Neoplasm Transplantation , Neoplasms, Experimental , Drug Therapy , Metabolism , Phytotherapy , Plant Extracts , Pharmacology , Therapeutic Uses , Xenograft Model Antitumor Assays , bcl-2-Associated X Protein , MetabolismABSTRACT
Objective To study the apoptosis of human colorectal cancer HT-29 cells induced by Aralia elata Seem leaf total saponin (ETS) and its effects on the expression of relevant proteins. Methods MTT assay was used to detect the proliferation of human colorectal cancer HT-29 cells cultivated with different concentrations (6.25, 12.5, 25, 50, 100, 200 mg/kg) of ETS. Hoechst33258 staining and laser confocal imaging were used to detect the apoptotic cells. Morphological changes were observed. The expressions of Bcl-2 and Bax were detected by immuno-histochemistry. Results ETS could induce apoptosis of HT-29 cells and apoptosis was in a dose-dependent manner in a certain range. ETS could decrease the expression of Bcl-2 and increase the expression of Bax in HT-29 cells (P<0.05, P<0.01), showing a significant dose-effect relationship. Conclusion ETS can induce the apoptosis of HT-29 cells, and the mechanism may be related to reducing the expression of Bcl-2 and increasing the expression of Bax.
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Objective To establish a hanging drop 3D cell culture model of human colon cancer cell (HT29) in 48-well cell culture plate,at the same time,through the comparison of several cell viability detection methods to determine the appropriate one for this cell culture way.Methods HT29 cells of 2 375,3 164,4 218,5 625,7 500 and 10 000/well were seeded in the bottom of the 48-well culture plate to form droplets.After 2 d of inversion culture,the cell spheroids were formed and incubated in medium for another 3 d.The volume of cell spheroids were measured,and the absorbance (A) values were detected through APH assay,MTT assay,MTT assay after digestion,CCK-8 assay and CCK-8 assay after digestion.The results were compared among different methods.Results After 5 d of culture,the cell spheroids were formed perfectly at the density of 2 375-10 000/well,and the volumes were in good linear with the original cell inoculation number at the density of 2 375-7 500/well.The A values of APH assay,MTT assay after digestion and CCK-8 assay after digestion increased with the increase of cell inoculation amount;But the cell ball digestion process was complex,and the cell viability was damaged.However,the A values of MTT and CCK-8 assay increased slowly.Conclusion The method of a hanging drop 3D cell culture model in 48-well culture plate combining with APH assay to detect cell viability is economical,accurate and easy to operate.
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Objective To establish a hanging drop 3D cell culture model of human colon cancer cell (HT29) in 48-well cell culture plate,at the same time,through the comparison of several cell viability detection methods to determine the appropriate one for this cell culture way.Methods HT29 cells of 2 375,3 164,4 218,5 625,7 500 and 10 000/well were seeded in the bottom of the 48-well culture plate to form droplets.After 2 d of inversion culture,the cell spheroids were formed and incubated in medium for another 3 d.The volume of cell spheroids were measured,and the absorbance (A) values were detected through APH assay,MTT assay,MTT assay after digestion,CCK-8 assay and CCK-8 assay after digestion.The results were compared among different methods.Results After 5 d of culture,the cell spheroids were formed perfectly at the density of 2 375-10 000/well,and the volumes were in good linear with the original cell inoculation number at the density of 2 375-7 500/well.The A values of APH assay,MTT assay after digestion and CCK-8 assay after digestion increased with the increase of cell inoculation amount;But the cell ball digestion process was complex,and the cell viability was damaged.However,the A values of MTT and CCK-8 assay increased slowly.Conclusion The method of a hanging drop 3D cell culture model in 48-well culture plate combining with APH assay to detect cell viability is economical,accurate and easy to operate.
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Objective To investigate the effects of Raddeanin A(RA)on apoptosis and cell cycle of hu-man colon cancer HT29 cells,and discuss the possible mechanism.Methods Different concentration of RA 1,2, 4,8,16μmol/L disposed HT29 cells 12,24,48 hour,3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bro-mide(MTT)assay was used for the cell proliferation;Hoechst33258 staining was performed to observe the effects of RA on apoptosis morphology;Flow cytometry(FCM)was devoted to calculate apoptosis rate and detect cell cycle;The expression of Cleaved-caspase-3,Cleaved-PARP,CyclinB,CDK1 proteins and other proteins were tested by Western blot(WB). Results RA could inhibit the proliferation of HT29 cells,and associated with concentration and time(P<0.05);The IC50of 12 h,24 h,48 h were(9.31 ± 0.63)μmol/L,(4.88 ± 1.02)mol/L,(3.60 ± 0.89) μmol/L.The nucleus pycnosis,fracture were detected by Hochest33258 staining,RA induced apoptosis in HT29 cells;Western blot(WB)assay showed that the expression of Cleaved-caspase-3,Cleaved-PARP rised.HT29 cells were arrested at the period of G2/M,and the CyclinB,CDK1 proteins down-regulated.WB result showed that PI3K, AKT proteins up-regulated,while p-PI3K,p-AKT protein down-regulated.Conclusion RA can inhibit the prolifer-ation of colon cancer HT29 cells and its mechanism is probably by regulating the PI3K/AKT signaling pathways which through inducing apoptosis and blocking the cell cycle.
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Objective: To explore the role and the possible mechanism of inhibitor of differentiation 1 (Id1) in angiogenesis of colon cancer. Methods: After transfection with Id1 over-expression vector plasmid, the expression levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) mRNAs and proteins in HT-29 cells were detected by real-time fluorescent quantitative PCR and Western blotting, respectively. The ability of tube formation of human umbilical vein endothelial cells (HUVECs) after culture with supernatant of HT-29 cells with Id1 overexpression for 24 h was observed by tube formation experiment. The tumorigenesis of HT-29 cells with Id1 over-expression in nude mice was observed, and the microvessel density (MVD) of transplanted tumor tissues was detected by immunohistochemistry, . Results: The expression levels of HIF-1α and VEGF mRNAs and proteins in HT-29 cells with Id1 over-expression were higher than those in the HT-29 cells transfected with empty vector (negative control) and the HT-29 cells without any transfection (blank control) (all P < 0.05). The number of tube formation of HUVECs after culture with supernatant of HT-29 cells with Id1 over-expression was higher than those of the negative control and the blank control groups (both P < 0.05). The ability of tmorigenesis and the number of MVD in Id1 overexpression group were both higher than those in the negative control and the blank control groups (all P < 0.05). Conclusion: Id1 may promote the angiogenesis of colon cancer by regulating the expressions of HIF-1α and VEGF.
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<p><b>OBJECTIVE</b>A subcutaneous transplantation tumor model of human HT-29 cells in nude mice was established to evaluate anticarcinogenic activities, and the apoptosis-regulated mechanism effect of aqueous extract of fermented wheat germ with Lactobacillus plantarum dy-1 (LFWGE).</p><p><b>METHODS</b>The HT-29 cells were transplanted via subcutaneous injection of 1×107 cells into the right flank of each nude mouse. Then, nude mice were treated for 30 d with LFWGE (high-dose 2 g/kg/d; low-dose 1 g/kg/d) and for 7 d with 5-fluorouracil (5-FU, 25 mg/kg/d) by gavage and intraperitoneal injection, respectively. An inhibition of tumor growth was observed.</p><p><b>RESULTS</b>Tumor volume and weights decreased significantly in both groups of nude mice treated with LFWGE. In addition, the cell apoptosis rate of the LFWGE group (2 g/kg/d, 60.1%±4.4%; 1 g/kg/d, 58.6%±6.9%) was significantly higher than that of the control group (11.5%±1.6%) and 5-FU group (32.1%±3.5%) as measured by the TUNEL assay. Moreover, the real-time fluorescent quantitative PCR and Western blot method further confirmed these enhancing apoptosis and growth inhibition effects. The involvement of LFWGE in inducing apoptosis was confirmed by the expression of Bax, Bcl-2, Caspase-3, and CyclinD1.</p><p><b>CONCLUSION</b>The results showed that LFWGE could induce subcutaneous transplantation tumor apoptosis in nude mice and could be as a natural nutrient supplements or chemopreventive agent in the treatment of human colon cancer.</p>
Subject(s)
Animals , Humans , Mice , Antineoplastic Agents , Chemistry , Pharmacology , Apoptosis , Caspase 3 , Genetics , Metabolism , Cyclin D1 , Genetics , Metabolism , Gene Expression Regulation, Neoplastic , HT29 Cells , Mice, Nude , Neoplasms, Experimental , Drug Therapy , Plant Extracts , Chemistry , Pharmacology , Proto-Oncogene Proteins c-bcl-2 , Genetics , Metabolism , bcl-2-Associated X Protein , Genetics , MetabolismABSTRACT
Objective To explore the mechanism of Tn antigen expression in colon cancer cells HT-29.Methods Tn(+) and Tn(-) cells were separated from human colon cancer cell line HT-29 by im-mune magnetic beads.Total RNA, genomic DNA ( gDNA) and cytoplasmic proteins in these cells were ex-tracted by using Trizol, DNA preparation kit and nuclear and cytoplasmic extraction reagents respectively.T-synthase activity was measured by a fluorescent assay.Cosmc and T-synthase transcriptional levels were ana-lyzed by RT-PCR using mRNA as the templates.The coding sequence ( CDS) and CpG islands of Cosmc were amplified by PCR using gDNA as the templates.Amplified products were analyzed on 1%agarose gel. The expected bands were purified, and then sequenced to examine Cosmc mutation.Wild type Cosmc ( Wt-Cosmc) were transfected into tumor cell lines and normal cells to define the function of Cosmc.The expres-sions of Cosmc protein in these cells were then examined by Western blot.Results Although no mutation appeared in HT-29-Tn(-) cells, the deletion of CDS and inactivity of T-synthase were observed in HT-29-Tn(+) cells.Additionally, transfected WtCosmc restored T-synthase activity and then decreased Tn antigen expression in Tn antigen positive cells.Conclusion The absence of CDS in Cosmc gene resulted in the loss of T-synthase activity and consequent Tn antigen expression in HT-29-Tn(+) cells.
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Objective: To screen and identify oxaliplatin-resistance-associated proteins in CRC (colorectal cancer) cell lines using proteomics technologies in order to find new biomarkers for individual therapy of CRC. Methods: Oxaliplatin-resistant human CRC cell line HT-29/L-OHP (oxaliplatin) was established. The total proteins in HT-29 and HT-29/L-OHP cells were extracted. The differentially expressed proteins between HT-29 and HT-29/L-OHP cells were screened and identified using 2-DE (two-dimensional gel electrophoresis) and MALDI-TOF-MS (matrix assisted laser desorption-ionization time-of-flight tandem mass spectrometry). Some proteins obtained were validated by Western blotting. Results: The 2-DE maps of total proteins in HT-29 and HT-29/L-OHP cells were established. Of the 38 protein spots identified as differentially expressed proteins (over two-fold, P < 0.05) between HT-29 and HT-29/L-OHP cells, 37 protein spots were positively identified by MALDI-TOF-MS (17 proteins were up-regulated and 20 proteins were down-regulated as compared with the parental HT-29 cells). The result of Western blotting showed that the PCBP1 [poly (C)-binding protein-1] and TUBB2A (tubulin beta 2A ) proteins were up-regulated while ANXA3 (annexin A3) and STIP1 (stress-induced-phosphoprotein 1) proteins were down-regulated in HT-29/L-OHP cells. The result of Western blotting was consistent with that of proteomics. Conclusion: There were 37 oxaliplatin-resistance-associated proteins in CRC identified in this study which may provide useful evidence in further research on mechanism of oxaliplatin-resistance in CRC. Copyright © 2013 by TUMOR.
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La vaginitis es un trastorno ginecológico frecuente producido por distintas causas, algunas de las cuales permanecen desconocidas. Bacteroides fragilis es el anaerobio más importante en bacteriología clínica. Algunas cepas son enterotoxigénicas y se asocian con síndromes intestinales y extraintestinales. Recientemente han sido aisladas de pacientes con vaginitis. En este trabajo se planteó investigar la posible asociación de B. fragilis enterotoxigénico con la vaginitis infecciosa. Fueron procesadas 265 muestras de exudado vaginal. 202 de mujeres sintomáticas y 63 mujeres sanas. La identificación de los microorganismos se realizó por métodos convencionales. En 31,2% de las pacientes sintomáticas se identificaron: Gardnerella vaginalis, Candida albicans, Mobiluncus, Mycoplasma hominis, Ureaplasma urealyticum y Streptococcus agalactiae. En 27 pacientes sintomáticas y en 5 mujeres sanas se identificó B. fragilis. Estas cepas fueron cultivadas en medio líquido e incubadas durante 48 h a 36° C en anaerobiosis. La toxicidad en los sobrenadantes se ensayó en células HT-29. 18 cepas de B. fragilis aisladas de pacientes sintomáticas fueron enterotoxigénicas, ya que indujeron alteraciones en la monocapa celular y en las células. No se identificó en mujeres sanas (P<0,05). 77,7% de las cepas de B. fragilis enterotoxigénicas no se encontraron asociadas con otros patógenos específicos. Este hecho sugiere que pudiera ser un agente causante de vaginitis, ya que el efecto de la enterotoxina sobre la E-cadherina del epitelio vaginal podría facilitar la invasión y su posible papel patógeno en la vagina. Esta es la primera investigación que asocia a Bacteroides fragilis enterotoxigénico como posible causa de vaginitis infecciosa.
Vaginitis is a common gynecologic disorder. It is due to several causes, some even unknown. Bacteroides fragilis is the most important anaerobe in clinical bacteriology, some strains of this group are notable for being enterotoxigenic and they have been associated with intestinal and extraintestinal syndromes. They have recently been isolated from patients with vaginitis. The purpose of this study was to investigate a possible association of enterotoxigenic B. fragilis with infectious vaginitis. 265 samples of vaginal exudate were processed, 202 from symptomatic patients and 63 healthy women. The identification of the microorganisms was carried out by conventional methods. In 31.2% of symptomatic patients were identified: Gardnerella vaginalis, Mobiluncus, Candida albicans, Mycoplasma hominis, Ureaplasma urealyticum and Streptococcus agalactiae. B. fragilis was identified in 27 symptomatic patients and 5 healthy women. These strains were cultivated in liquid medium and incubated during 48 h at 36°C in anaerobe chambers. Supernatant activity was assayed in HT-29 cells. Eighteen B. fragilis strains isolated from symptomatic patients were enterotoxigenic, because induced alterations in target cell morphology. It was not identified in healthy women (P<0.05). 77.7% of enterotoxigenic B. fragilis strains were not associated with other specific pathogens. This fact suggests that enterotoxigenic B. fragilis could be a cause for vaginitis. The effect of enterotoxin on E-cadherin of vaginal epithelium could facilitate invasion and its possible pathogenic role in the vagina. This is the first report that associates enterotoxigenic Bacteroides fragilis as a possible cause of infectious vaginitis.
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Adolescent , Adult , Female , Humans , Middle Aged , Young Adult , Bacteroides fragilis/pathogenicity , Enterotoxins/analysis , Vaginosis, Bacterial/microbiology , Bacterial Toxins/analysis , Bacteroides fragilis/isolation & purification , Bacteroides fragilis/metabolism , Coinfection , Candida albicans/isolation & purification , Candidiasis, Vulvovaginal/microbiology , Exudates and Transudates/microbiology , Gardnerella vaginalis/isolation & purification , Metalloendopeptidases/analysis , Mycoplasma Infections/microbiology , Mycoplasma hominis/isolation & purification , Staphylococcal Infections/microbiology , Vagina/microbiologyABSTRACT
AMPK (AMP-activated protein kinase) is highly conserved in eukaryotes, where it functions primarily as a sensor of cellular energy status. Recent studies indicate that AMPK activation strongly suppresses cell proliferation in non-malignant cells as well as in tumor cells. In this study, quercetin activated AMPK in MCF breast cancer cell lines and HT-29 colon cancer cells, and this activation of AMPK seemed to be closely related to a decrease in COX-2 expression. The application of a COX-2 inhibitor or cox-2(-/-) cells supported the idea that AMPK is an upstream signal of COX-2, and is required for the anti-proliferatory and pro-apoptotic effects of quercetin. The suppressive or growth inhibitory effects of quercetin on COX-2 were abolished by treating cancer cells with an AMPK inhibitor Compound C. These results suggest that AMPK is crucial to the anti-cancer effect of quercetin and that the AMPK-COX-2 signaling pathway is important in quercetin-mediated cancer control.
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Humans , AMP-Activated Protein Kinases/antagonists & inhibitors , Anticarcinogenic Agents/pharmacology , Antioxidants/pharmacology , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclooxygenase 2/genetics , Cyclooxygenase 2 Inhibitors/pharmacology , Enzyme Activation , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Quercetin/pharmacologyABSTRACT
Objective To investigate the regulative effect of cyclooxygenase-2 (COX-2) 3'-UTR in HT29 colon cancer cells. Methods Total RNA was extracted from HT29 colon cancer cells and used as a template to amplify COX-2 gene by reverse transcription polymerase chain reaction. Using PCR technique to construct a series of luciferase reporter gene expression vectors containing various regions of the 3'-UTR of COX-2 (including the whole gene region, gene region between 1 to 156 bp, gene region between 1 to 347 bp, gene region between 1 to 1006 bp, gene region between 156 to 347 bp and gene region between 157 to 2217 bp). These reporter gene expression vectors and pRL-SV40 were co-transfected in HT29 colon cancer cells by Lipofectamine 2000. The relative luciferase activity of the HT29 colon cancer cells was tested. All data were analyzed via t test. Results The luciferase activity was reduced by 70.4%, 37.4%, 64.8% and 24.2% in HT29 colon cancer cells transfected with the whole COX-2 gene region, gene region between 1 to 156 bp, gene region between 1 to 347 bp and gene region between 156 to 347 bp, respectively (t = 6.13, 7.73, 9.75, 3.92, P < 0.05). No obvious changes of luciferase activity were observed in HT29 colon cancer cells transfected with gene regions between 1 to 1006 bp and between 157 to 2217 bp (t = 0.13, 0.01, P > 0.05). Conclusions A region between 156-347 bp in the 3'-UTR of COX-2 has been found which can down-regulate the expression of COX-2 with the cooperation of the ARE element. The 3'-UTR of COX-2 contains several control elements that regulate the expression of COX-2 in colon cancer cells.
ABSTRACT
La vaginitis es un diagnóstico común en ginecología. Su presencia obedece a diversas causas, algunas aún desconocidas. Bacteroides fragilis es el anaerobio más importante desde el punto de vista clínico. Entre otros factores de virulencia, algunas cepas producen una enterotoxina asociada con diarrea. Estas cepas han sido aisladas tanto de muestras intestinales como extra intestinales. Por la existencia de procesos inflamatorios en la mucosa cérvico-vaginal de etiología desconocida se investiga a B. fragilis enterotoxigénico en pacientes con vaginitis. Se procesaron 140 muestras de pacientes y 40 de controles sanos. De las pacientes sintomáticas se aislaron 15 cepas de B. fragilis y ninguna en los controles (P<0,05). Posteriormente, fueron cultivadas en anaerobiosis, usando caldo cerebro-corazón suplementado con vitamina K1 y hemina durante 48 horas a 36°C. El sobrenadante se obtuvo por centrifugación y su actividad se ensayó en células HT-29. Doce (80%) cepas produjeron alteraciones en la monocapa celular, manifestada por desprendimiento, disolución de los acúmulos, expansión y disgregación de las células, superando en algunos casos la toxicidad observada en el control positivo. En siete pacientes, B. fragilis enterotoxigénico no estuvo asociado a patógenos específicos. La presencia de B. fragilis enterotoxigénico en pacientes con vaginitis plantea la necesidad de definir su papel en la etiología de esta entidad clínica.
Vaginitis is a common diagnosis in the centers of gynecological attention. It is due to several causes, some even unknown. Bacteroides fragilis is the most important anaerobe in clinical practice; some strains produce an enterotoxin associated with diarrhea. Enterotoxigenic B. fragilis has been isolated from intestinal as well as extra intestinal samples. Because inflammatory processes unknown etiology it was investigated B. fragilis in the cervical-vaginal mucous in the patients with vaginitis. 140 samples were processed from symptomatic patients and 40 from healthy controls. 15 strains of B. fragilis were isolated from symptomatic patients while none were found in controls (P<0,05). These strains were cultivated in anaerobic chambers, cultured in brain heart infusion supplemented with vitamin K1 and hemine during 48 hours at 36°C. Supernatant were obtained by centrifugation and its activity assayed in HT-29 cells. Twelve (80%) of the isolated induced alterations in target cell morphology characterized by cell detachment, breakup of cell clumps, expansion and degradation of cells, some cases revealed a higher cytotoxic activity than the positive control. In seven patients enterotoxigenic B. fragilis was not associated to specific pathogens. The presence of enterotoxigenic B. fragilis in patients with vaginitis raises the necessity to define its role in the etiology of this clinical entity.
ABSTRACT
BACKGROUND/AIMS: The peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear receptor highly expressed in the colon which plays an anti-inflammatory role through the inhibition of nuclear factor-kappaB (NF-kappaB) pathway. Probiotics have been shown to exert beneficial effects on inflammatory bowel diseases. However, the exact mechanism by which probiotics exert protection against intestinal inflammation is not well understood. The aims of this study were to evaluate the attenuation of inflammatory response by probiotics in intestinal epithelial cells and to study the association between probiotics and PPARgamma. METHODS: HT-29 human epithelial cells were stimulated with LPS (20microgram/mL) and probiotics, Lactobacillus casei (L. casei) (10(5)-10(7) cfu/mL), or with LPS (20microgram/mL) alone for 24 hours. Interleukin-8 (IL-8), cyclooxygenase-2 (COX-2), toll-like receptor-4 (TLR-4) and PPARgamma mRNA expressions were assessed by RT-PCR. IL-8 protein secretion was measured by ELISA. HT-29 cells were transfected with tk promoter-luciferase plasmid containing a peroxisome proliferator response element (PPRE). After stimulation with L. casei or PPARgamma agonist (15d-PGJ2 or ciglitazone), luciferase activities were measured. RESULTS: LPS induced IL-8, COX-2, TLR-4 mRNA expression, and IL-8 protein secretion in HT-29 cells. Treatment with LPS and L. casei in comparison with LPS stimulation alone lowered IL-8, COX-2, TLR-4 mRNA expression, and IL-8 protein secretion. L. casei increased PPARgamma mRNA expression in dose-dependent manner. L. casei activated PPRE in HT-29 cells transfected with PPRE3-tk-luciferase construct. CONCLUSIONS: Probiotics, L. casei, suppresses the expression of inflammatory mediators in intestinal epithelial cells. The anti-inflammatory action of L. casei might be partially related to PPARgamma activation.