scholarly journals Metformin’s Effects on Apoptosis of Esophageal Carcinoma Cells and Normal Esophageal Epithelial Cells: An In Vitro Comparative Study

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Jianwei Peng ◽  
Xubin Jing ◽  
Jialing Wu ◽  
Danmian Hong ◽  
Xi Hu ◽  
...  

The effect of metformin on human esophageal normal and carcinoma cells remains poorly understood. We aim to investigate the different antiproliferation effects and underlying distinct molecular mechanisms between these two types of cells. Human esophageal squamous cell carcinoma cell line, EC109, and normal esophageal epithelial cell line, HEEC, were used in the experiment. The cell survival rate was determined by cell counting kit-8 (CCK-8). Cell apoptosis was analyzed by flow cytometry. The mRNA and protein levels of signal transducer and activator of transcription 3 (Stat3) were detected by real-time quantitative PCR and western blot. Interleukin-6 (IL-6) was added to activate Stat3. The level of intracellular reactive oxygen species (ROS) was assessed by a DCFH-DA fluorescent probe. Metformin had more significant inhibitory effects on cell proliferation in EC109 cells than HEECs. Metformin induced apoptosis of EC109 cells in a dose-dependent manner instead of HEECs. The expression of Stat3 in both mRNA and protein levels was higher in EC109 cells than HEECs. Further study revealed that metformin may attenuate the phosphorylation of the Stat3 and the Bcl-2 expression, which was restored by IL-6 partly in EC109 cells but not HEECs. On the contrary, metformin increased the level of ROS in both the cell lines, but this intracellular ROS variation had no effect on apoptosis. Metformin has different functional roles on the apoptosis in esophageal carcinoma cells and normal esophageal cells. Therefore, the Stat3/Bcl-2 pathway-mediated apoptosis underlies the cell-type-specific drug sensitivity, suggesting metformin possesses a therapeutic activity and selectivity on esophageal cancer.

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1715
Author(s):  
Xin Luo ◽  
Qiangqiang Deng ◽  
Yaru Xue ◽  
Tianwei Zhang ◽  
Zhitao Wu ◽  
...  

Pulmonary fibrosis is a severe and irreversible interstitial pulmonary disease with high mortality and few treatments. Magnesium lithospermate B (MLB) is a hydrosoluble component of Salvia miltiorrhiza and has been reported to have antifibrotic effects in other forms of tissue fibrosis. In this research, we studied the effects of MLB on pulmonary fibrosis and the underlying mechanisms. Our results indicated that MLB treatment (50 mg/kg) for seven days could attenuate bleomycin (BLM)-induced pulmonary fibrosis by reducing the alveolar structure disruption and collagen deposition in the C57 mouse model. MLB was also found to inhibit transforming growth factor-beta (TGF-β)-stimulated myofibroblastic transdifferentiation of human lung fibroblast cell line (MRC-5) cells and collagen production by human type II alveolar epithelial cell line (A549) cells, mainly by decreasing the expression of TGF-β receptor I (TGF-βRI) and regulating the TGF-β/Smad pathway. Further studies confirmed that the molecular mechanisms of MLB in BLM-induced pulmonary fibrosis mice were similar to those observed in vitro. In summary, our results demonstrated that MLB could alleviate experimental pulmonary fibrosis both in vivo and in vitro, suggesting that MLB has great potential for pulmonary fibrosis treatment.


2011 ◽  
Vol 89 (10) ◽  
pp. 705-711 ◽  
Author(s):  
Walid Abu Arab ◽  
Rami Kotb ◽  
Marco Sirois ◽  
Éric Rousseau

Non-small cell lung cancer (NSCLC) is a major health problem. Surgery is the only potential curative treatment, in spite of the high recurrence and mortality rates. Low molecular weight heparins (LMWH) have been suggested to have a positive impact on the outcome of various cancers, mainly attributed to their anticoagulant properties; yet a direct antineoplastic effect has not been excluded. We thought to evaluate the direct effect of the LMWH enoxaparin on the human lung adenocarcinomic epithelial cell line A549 and to determine potential antiproliferative and antimetastatic effects that could guide future trials. A549 cells were cultured with different concentrations of enoxaparin (1–30 U/mL). Cell counting was performed at 24, 48, and 72 h. Detection of c-Myc protein and CD44 protein was performed by electrophoresis and Western blotting. Statistical analysis was performed using paired Student’s t tests. Cell counts were decreased with increasing concentrations and time of exposure to enoxaparin. This corresponds to decreased expression of c-Myc and CD44. In conclusion, enoxaparin displayed a direct dose and exposure duration dependent suppressor effect on A549 cell proliferation and the expression of both c-Myc and CD44 in vitro, suggesting reduced proliferative and metastatic potentials of these cells.


Endocrinology ◽  
2009 ◽  
Vol 150 (2) ◽  
pp. 897-905 ◽  
Author(s):  
Narayanan Krishnaswamy ◽  
Ghislain Danyod ◽  
Pierre Chapdelaine ◽  
Michel A. Fortier

Interferon-τ (IFNτ) is the embryonic signal responsible for pregnancy recognition in ruminants. The primary action of IFNτ is believed to be mediated through inhibition of prostaglandin F2α (PGF2α) released from the endometrial epithelial cells in response to oxytocin (OT). Our working hypothesis was that the antiluteolytic effect of IFNτ also involved modulation of PG production downstream of OT receptor (OTR) and/or cyclooxygenase 2 (COX2). There is currently no OT-sensitive endometrial cell line to study the molecular mechanisms underlying our hypotheses. Therefore, we established an immortalized bovine endometrial epithelial cell line (bEEL) exhibiting OT response. These cells were cytokeratin positive, expressed steroid receptors, and exhibited preferential accumulation of PGF2α over PGE2. The bEEL cells were highly sensitive to OT, showing time- and concentration-dependent increase in COX2 transcript and protein and PGF2α accumulation. Interestingly, IFNτ (20 ng/ml) significantly reduced OT-induced PGF2α accumulation, but surprisingly, the effect was not mediated through down-regulation of either OTR or COX2. Rather, IFNτ up-regulated COX2 in a time- and concentration-dependent manner while decreasing OT-induced PG accumulation. This suggests that COX2 is not a primary target for the antiluteolytic effect of IFNτ. Because IFNτ reduced OT-stimulated PGF2α accumulation within 3 h, the mechanism likely involves a direct interference at the level of the OT signaling or transcription in addition to the down-regulation of OTR observed in vivo. In summary, bEEL cells offer a unique in vitro model for investigating the cellular and molecular mechanisms underlying OT and IFNτ response in relation with luteolysis and recognition of pregnancy in the bovine. Interferon-τ acts as a competitive partial agonist, stimulating basal but inhibiting oxytocin- and phorbol myristate acetate-stimulated prostaglandin F2α production in immortalized bovine endometrial epithelial cells.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4318-4318 ◽  
Author(s):  
Julian Baumeister ◽  
Nicolas Chatain ◽  
Annika Hubrich ◽  
Caroline Küstermann ◽  
Stephanie Sontag ◽  
...  

Abstract Myeloproliferative neoplasms (MPN) are a heterogeneous group of malignancies including polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The JAK2V617F mutation can be found in 90% of PV and approximately 50% of ET and PMF patients. Hypoxia-inducible factors (HIFs) are master transcriptional regulators of the response to decreases in cellular oxygen levels. Unveiling the function of deregulated HIF-1 signaling in normal and malignant hematopoiesis was the aim of several recent publications, highlighting the importance of HIF-1 for the maintenance of leukemic stem cells (LSCs) in acute and chronic myeloid leukemia (AML/CML). In a JAK2V617F knock-in mouse model and in patients, JAK2V617F was shown to induce the accumulation of reactive oxygen species (ROS) in the hematopoietic stem cell compartment, leading to a stabilization of HIF-1α protein. Further, aberrant STAT5 and PI3K/AKT/mTOR signaling induced HIF-1α expression on the transcriptional and translational level. Ruxolitinib treatment inhibited growth and reduced the expression of HIF-1α and its target gene VEGF in the JAK2V617F human erythroleukemia cell line HEL. In several leukemic cell lines constitutive expression of HIF-1α was reported, even under normoxic conditions. However, it still remains unknown whether HIF-1α plays a role in JAK2V617F positive MPN. In this study, we investigated the role HIF-1α signaling in JAK2V617F positive MPN in vitro. We retrovirally transduced the murine bone marrow cell line 32D with JAK2V617F or JAK2WT. Western blot analysis revealed significant increases in HIF-1α protein levels in JAK2V617F positive cells compared to JAK2WT controls after cultivation in normoxic conditions and this effect was abrogated by treatment with the JAK1/JAK2 inhibitor ruxolitinib. Inhibition of HIF-1, binding to hypoxia response elements (HRE), by low doses of echinomycin (1 nM), significantly impaired proliferation and survival. Using an Annexin-V/7-AAD flow cytometry assay apoptosis was found to be selectively induced in JAK2V617F positive, but not JAK2WT cells after echinomycin treatment. Additionally, BrdU/7-AAD cell cycle analysis revealed that only JAK2V617F positive cells were significantly arrested in G0/1 phase. These findings were consistent with shRNA-mediated knockdown (KD) of HIF-1α in JAK2V617F transduced 32D cells in presence but not the absence of HIF-2 antagonist 2. Inhibition of HIF-2 was necessary due to a compensatory increase of HIF-2α protein levels, shown by Western Blot analysis, counteracting HIF-1α-KD mediated effects. We isolated PBMCs and BMMNCs from JAK2V617F positive patients or healthy controls using Ficoll density gradient centrifugation. Echinomycin significantly abrogated the colony formation ability alone and in combination with ruxolitinib. In vitro treatment with echinomycin significantly decreased cell number and viability of 8 JAK2V617F positive BMMNC samples (4 PV, 3 PMF, 1 preMF; p[1nM]=0.0169, p[5nM]=0.0009) and 7 PBMC samples (6 PV, 1 PMF; p[1nM]=0.0156, p[5nM]=0.0156) in a dose-dependent manner. In contrast, PBMCs from 6 healthy donors were unaffected by the treatment. The same effect was observed in heterozygous and homozygous iPS cell-derived progenitors from JAK2V617F positive PV patients, whereas JAK2WT cells were unaffected by the treatment. Collectively, our data indicate that targeting HIF-1 might represent a novel therapeutic approach in classical Philadelphia-chromosome-negative MPN. Disclosures Brümmendorf: Pfizer: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Janssen: Consultancy; Merck: Consultancy; Takeda: Consultancy.


1991 ◽  
Vol 260 (6) ◽  
pp. F906-F912 ◽  
Author(s):  
A. Grenader ◽  
D. P. Healy

Proximal tubules have been shown to produce dopamine (DA) from (-)-3-(3,4-dihydroxyphenyl)-L-alanine (L-dopa) and to express DA1 dopamine (DA1) receptors linked to inhibition of sodium transport. The LLC-PK1 renal epithelial cell line expresses proximal tubule cell-like properties in vitro. Here, we sought to determine whether the LLC-PK1 cell line would be a useful model system to study dopaminergic mechanisms in vitro. LLC-PK1 cells contained high levels of aromatic L-amino acid decarboxylase (AADC) (Km 0.19 +/- 0.08 mM, Vmax 3.69 +/- 0.57 nmol.mg-1.min-1) and converted L-dopa to DA in a nonsaturable fashion up to 1 mM L-dopa. DA production was blocked by the AADC inhibitor carbidopa. Dopamine stimulated adenosine 3',5'-cyclic monophosphate (cAMP) accumulation in LLC-PK1 cells in a dose-dependent manner (50% effective concentration, 1.53 +/- 0.38 microM; maximal stimulation, 46.6 +/- 10.88 pmol/mg protein); this effect was blocked by addition of DA1-receptor antagonists. L-Dopa also stimulated cAMP accumulation, and this effect was attenuated by an equimolar concentration of carbidopa and blocked by the DA1 antagonist Sch 23390. These results indicate that LLC-PK1 cells convert L-dopa to DA, which then stimulates cAMP via a DA1 receptor coupled to activation of adenylate cyclase. Moreover, the demonstration that locally formed DA can act as an autocrine/paracrine substance in LLC-PK1 cells in vitro is consistent with a role for DA as an autocrine/paracrine substance in vivo.


2020 ◽  
Vol 11 (2) ◽  
pp. 174-180
Author(s):  
Hesam Saghaei Bagheri ◽  
Seyed Hossein Rasta ◽  
Seyedeh Momeneh Mohammadi ◽  
Ali Akbar Rahim Rahimi ◽  
AliAkbar Movassaghpour ◽  
...  

Introduction: Laser radiation is a promising strategy against various malignancies. Recent studies have shown that the application of low-power laser therapy (LPLT) at different doses and exposure times could modulate the growth dynamic of tumor cells. Based on the type of laser, LPLT could potentially trigger cell proliferation, differentiation, and apoptosis in different cell lines. Methods: In this study, MTT assay was used to monitor the effect of low and high laser intensities on the viability of normal and cancer lymphocytes. The protein levels of Ki-67 (a proliferation marker) and Caspase-3 (an apoptosis factor) were measured in human peripheral mononuclear cells (PBMCs) and the B-lymphoblastic cell line (Nalm-6) using flow cytometry after being-exposed to 630-nm LPLT at low (2, 4, 6, and 10 J/cm2 ) and high (15, 30, 60, and 120 J/cm2 ) energy densities in a continuous mode for 48 and 72 hours. Results: By using higher energy densities, 60 and 120 J/cm2 , a significant decrease was shown in the viability of Nalm-6 cells, which reached 6.6 and 10.1% after 48 hours compared to the control cells (P<0.05). Notably, Cell exposure to doses 30, 60, and 120 J/cm2 yielded 7.5, 12.9, and 21.6 cell viability reduction after 72 hours. The collected data showed that the high-intensity parameters of LPLT (15 to 120 J/cm2 ) promoted significant apoptotic changes in the exposed cells coincided with the activation of Caspase-3 compared to the none-treated control cells (P<0.05). The data further showed the stimulation of the Ki-67 factor both in primary PBMCs and the lymphoblastic cell line treated with LPLT at energy densities of 4 and 6 J/cm2 (P<0.05), indicating enhanced cell proliferation. Similar to Nalm-6 cells, primary PBMCs showed apoptosis after 48 hours of being exposed to doses 60, and 120 J/cm2 , indicated by increased Caspase-3 levels (P<0.05). As expected, the Nalm-6 cells were resistant to cytotoxic effects of laser irradiation in the first 48 hours (P>0.05) compared to normal PBMCs. The exposure of Nalm-6 cells to low-intensity laser intensities increased a proliferation rate compared to the PBMCs treated with the same doses. Conclusion: We showed the potency of LPLT in the induction of apoptosis and proliferation in human primary PBMCs and Nalm-6 cells in a dose and time-dependent manner after 72 hours.


2019 ◽  
Vol 39 (5) ◽  
Author(s):  
Xu Li ◽  
Junjie Xing ◽  
Hantao Wang ◽  
Enda Yu

AbstractGrowing evidence has uncovered that SLC34A2 plays an evident role in the progression in several types of tumors. However, the biological function and underlying molecular mechanisms of SLC34A2 remain largely unknown. Here, we indicated that SLC34A2 expression was markedly increased in SW480 and HT29 cell line cells compared with that in normal colorectal epithelial cell line cells. Array analysis displayed that the expression of enhancer of zeste 2 (EZH2) decreased considerably when SLC34A2 was knocked down. We demonstrated that SLC34A2 induced EZH2 expression and activated its promoter activity. Serial 5′ deletion and site-directed mutagenesis revealed that the induction of EZH2 expression by SLC34A2 was dependent upon the hypoxia-inducible factor 1 (HIF-1)-2 binding site directly within EZH2 promoter. Moreover, HIF-1 activation was proved essential for SLC34A2-induced EZH2 expression. Reactive oxygen species (ROS) generation contributed to the stabilization of HIF-1α by leading to the binding of HIF-1α to the EZH2 promoter, which resulted in increased EZH2 expression. Additionally, we showed that the inhibition of both HIF-1α expression and ROS generation by YC-1 or BHA, respectively, decreased SLC34A2-induced EZH2 overexpression. Significantly, SLC34A2-induced EZH2 overexpression promoted the proliferation and chemo-resistance to apoptosis in colorectal cancer (CRC) cells in vitro and in vivo. Altogether, we conclude that the SLC34A2-ROS-HIF-1-induced overexpression of EZH2 promotes CRC cells proliferation and chemo-resistance to apoptosis. SLC34A2-ROS-HIF-1-EZH2 signaling pathway might serve as a novel therapeutic target against CRC.


2018 ◽  
Vol 48 (6) ◽  
pp. 2528-2538 ◽  
Author(s):  
Shengjuan Wei ◽  
Mengmeng Zhang ◽  
Yueying Zheng ◽  
Peishi Yan

Background/Aims: Our study aims to characterize functions of ZBTB16 gene in the process of intramuscular fat (IMF) deposition and metabolism of bovine, thereby providing insights into mechanisms for the use of ZBTB16 in fat management. Methods: Primary preadipocytes derived from bovine IMF tissue were isolated and used as the in vitro cell model. An adenovirus Ad-ZBTB16 was transfected into bovine preadipocytes to overexpress the ZBTB16 gene. By using real-time quantitative PCR (RT-qPCR), western blotting, Oil Red-O staining, glycerol-3-phosphate dehydrogenase (GPDH) activity assay, and cell counting kit-8 (CCK-8) test, adipogenic and proliferative signals in adipocytes were monitored to investigate effects of ZBTB16 on adipogenesis of bovine preadipocytes. Results: After transfection, mRNA and protein levels of ZBTB16 gene were significantly increased. Enhanced ZBTB16 significantly promoted preadipocyte differentiation, as evidenced by accelerated lipid accumulation, enhanced GPDH activity, consistently increased mRNA expressions of adipogenic key transcription factors PPARγ, C/EBPα, FABP4, and ADIPOQ, and markedly increased protein expressions of PPARγ and FABP4. No difference was observed concerning proliferation of preadipocytes after treatment with Ad-ZBTB16. Furthermore, relative mRNA levels of brown adipocyte selective genes (PRDM16, UCP1, Cidea, Cox8b, and PGC-1α) and beige adipocyte selective genes (CD137, TMEM26, and Tbx1) as well as UCP1 protein expression were significantly increased by Ad-ZBTB16. Meanwhile, Ad-ZBTB16 treatment remarkably induced mitochondrial biogenesis and increased relative mitochondrial DNA (mtDNA) copy number in bovine adipocytes. Conclusion: These results suggest that ZBTB16 overexpression can promote white adipogenesis and induce brown-like adipocyte formation for bovine white intramuscular preadipocytes.


2015 ◽  
Vol 37 (2) ◽  
pp. 116-119 ◽  
Author(s):  
T O Kochubei ◽  
O Y Maksymchuk ◽  
O O Piven ◽  
L L Lukash

Aim: To study the effects of total phytohemagglutinin (PHA) and its isolectins on cell death and apoptosis in human HEp-2 carcinoma cells and to analyze the possible molecular mechanisms of lectin induced apoptosis. Materials and Methods: The commercial preparation of the kidney beans (Phaseolus vulgaris) lectins and HEp-2 cells were used. Apoptosis index was determined using acridine orange and ethidium bromide staining. The expression levels of apoptosis mediator cleaved caspase-3 and proapoptotic Bax protein were studied by Western blot analysis. The gene expression levels were analyzed by qPCR. Results: PHA and its isolectins induced apoptosis in HEp-2 cells accompanied by the increased expression of caspase-3 cleaved form, with PHA-E being the most effective. The treatment of HEp-2 cells with PHA or its isolectins resulted in a marked increase of Bax on both mRNA and protein levels. Conclusions: PHA and its isolectins were shown to induce the apoptosis in human HEp-2 carcinoma cells via increasing proapoptotic protein Bax and activating caspases-3.


2021 ◽  
Vol 16 (10) ◽  
pp. 1934578X2110460
Author(s):  
Raziyeh Hashemi ◽  
Mojtaba Farahi ◽  
Ramin Bagheri ◽  
Mehrdad Iranshahi ◽  
Sepehr Torabinejad ◽  
...  

Background and aims: Radiotherapy ranks among the most important procedures in ovarian cancer therapy. However, radioresistance is becoming more prevalent and is one of the main causes of poor clinical outcomes. To overcome this problem, radiosensitizers may be used. The present study aimed to evaluate the radiosensitizing properties of galbanic acid (GBA) on ovarian cancer cells in vitro. Materials and methods: OVCAR-3 cells, an ovarian cancer cell line, were treated with increasing concentrations of GBA (5, 10, 20, and 40 μg/mL) for 24, 48, and 72 h to determine its half-maximal inhibitory concentration (IC50). Cell viability was assessed by alamar Blue assay. The cells treated with 10 μg/mL GBA for 24 h were exposed to increasing doses of radiation (1, 2, and 4 Gy) and the survival fraction was investigated by clonogenic assay. Results: Assessment of cell viability indicated that GBA caused toxicity in a dose-dependent manner. Additionally, GBA pretreatment significantly improved the radiosensitivity of the cells, and survival fraction data indicated synergy between GBA and radiation. Conclusion: Taken together, the current findings highlight GBA as a potent radiosensitizing agent; however, further research is required to determine the molecular mechanisms of the observed effect both in vitro and in vivo. It is also suggested that the radiosensitization effect of GBA on other cell types should be studied in the future.


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