lithium-chloride and Adenocarcinoma

Resistance to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis has been reported in some cancer cells, including AGS human gastric adenocarcinoma cells. Reducing this resistance might shed light on the treatment of human gastric adenocarcinoma. In this study, we examined whether glycogen synthase kinase-3 (GSK-3) inhibitors can restore TRAIL responsiveness in gastric adenocarcinoma cells. The effect of two GSK-3 inhibitors, SB-415286, and LiCl, on apoptosis signaling of TRAIL in human gastric adenocarcinoma cell lines and primary gastric epithelial cells was analyzed. Both inhibitors can sensitize gastric adenocarcinoma cells, but not primary gastric epithelial cells, to TRAIL-induced apoptosis by increasing caspase-8 activity and its downstream signal transmission. Adding p53 siRNA can downregulate GSK-3 inhibitor-related sensitization to TRAIL-induced apoptosis and caspase-3 activity. GSK-3 inhibitors strongly activate the phosphorylation of JNK. Inhibition of JNK leads to earlier and more intense apoptosis, showing that the activation of JNK may provide anti-apoptotic equilibrium of pro-apoptotic cells. Our observations indicate that GSK-3 inhibitors can sentize AGS gastric adenocarcinoma cells to TRAIL-induced apoptosis. Therefore, in certain types of gastric adenocarcinoma, GSK-3 inhibitor might enhance the antitumor activity of TRAIL and mightbe a promising candidate for the treatment of certain types of gastric adenocarcinoma.

Topics: Adenocarcinoma; Aminophenols; Apoptosis; Cell Line, Tumor; Drug Screening Assays, Antitumor; Glycogen Synthase Kinase 3; Humans; Lithium Chloride; Maleimides; Protein Kinase Inhibitors; RNA, Small Interfering; Stomach Neoplasms; TNF-Related Apoptosis-Inducing Ligand; Tumor Suppressor Protein p53

The Wnt/β‑catenin signaling pathway has been reported to regulate cisplatin resistance in several types of cancer cell. The present study aimed to investigate the role and underlying mechanism of Wnt/β‑catenin signaling in cisplatin resistance of lung adenocarcinoma cells. Wild‑type and cisplatin‑resistant A549 human lung adenocarcinoma cells (A549/WT and A549/CDDP, respectively) were cultured in vitro and exposed to different cisplatin concentrations. Cells were incubated with 10 mM lithium chloride (LiCl) to activate β‑catenin signaling. Cell proliferation was determined using the MTS assay. Cell apoptosis was evaluated using Annexin V/propidium iodide double staining, followed by flow cytometry. β‑catenin was knocked down using small interfering RNA (siRNA). The intracellular distribution of β‑catenin was determined by immunocytochemistry, and the mRNA and protein expressions of target genes were examined by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. β‑catenin and B‑cell lymphoma‑extra large (Bcl‑xl) were significantly upregulated in A549/CDDP cells compared with A549/WT cells (P<0.05). LiCl reduced the sensitivity of A549/WT cells to cisplatin (P<0.01); and upregulated, increased phosphorylation (P<0.05) and enhanced nuclear translocation of β‑catenin. LiCl also significantly elevated the mRNA and protein expression levels of Bcl‑xl (P<0.05). Notably, silencing of β‑catenin with siRNA decreased the mRNA and protein expression of Bcl‑xl, and sensitized A549/WT cells to cisplatin (P<0.01). The findings of the current study suggest that upregulation of β‑catenin signaling may contribute to cisplatin resistance in lung adenocarcinoma cells by upregulating Bcl‑xl. Therefore, molecular targeting of Wnt/β‑catenin signaling may sensitize lung cancer cells to cisplatin.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Antineoplastic Agents; bcl-X Protein; Cisplatin; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Gene Expression; Gene Expression Regulation, Neoplastic; Humans; Inhibitory Concentration 50; Lithium Chloride; Lung Neoplasms; Up-Regulation; Wnt Signaling Pathway

Cervical cancer continues to threaten women's health worldwide, and the incidence of cervical adenocarcinoma (AD) is rising in the developed countries. Previously, we showed that glucose-regulated protein 58 (Grp58) served as an independent factor predictive of poor prognosis of patients with cervical AD. However, the molecular mechanism underlying the involvement of Grp58 in cervical carcinogenesis is currently unknown.. DNA microarray and enrichment analysis were used to identify the pathways disrupted by knockdown of Grp58 expression.. Among the pathway identified, the WNT signaling pathway was one of those that were significantly associated with knockdown of Grp58 expression in HeLa cells. Our experiments showed that β-catenin, a critical effector of WNT signaling, was stabilized thereby accumulated in stable Grp58 knockdown cells. Membrane localization of β-catenin was observed in Grp58 knockdown, but not control cells. Using a transwell assay, we found that accumulated β-catenin induced by Grp58 knockdown or lithium chloride treatment inhibited the migration ability of HeLa cells. Furthermore, an inverse expression pattern of Grp58 and β-catenin was observed in cervical tissues.. Our results demonstrate that β-catenin stability is negatively regulated by Grp58 in HeLa cells. Overexpression of Grp58 may be responsible for the loss of or decrease in membranous β-catenin expression in cervical AD.

Topics: Adenocarcinoma; beta Catenin; Female; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; HeLa Cells; Humans; Lithium Chloride; Oligonucleotide Array Sequence Analysis; Protein Disulfide-Isomerases; Protein Stability; Uterine Cervical Neoplasms; Wnt Signaling Pathway

Lithium is a common mood stabilizer to treat bipolar disorder. It has a narrow window of therapeutic action and its mechanism of action and possible side effects are still not fully understood. Lithium is a potent inhibitor of glycogen synthase kinase 3β (GSK-3β). Previous studies indicated that lithium can induce cell cycle arrest by stabilization of p53. In order to further elucidate the signaling mechanism of lithium-induced cell cycle arrest and its potential pharmacological effect on p53 transformed cell lines, we studied the effect of lithium on the rat fibroblast cell line R6 and a p53(Val135) transformed cell line R6T2 (hereafter referred to as T2).. We monitored the effects of lithium on cell cycle progression by FACS analysis and the activation of MAPK signaling pathways by Western blot using anti-phospho-MAPK antibodies in R6 and T2.. We report here lithium can induce G2/M arrest in T2 independent of β-catenin signals. Lithium increases phosphorylation of extracellular signal-regulated kinases (ERKs) leading to the up-regulation of p53 levels and subsequent G2/M arrest. Lithium also induced phosphorylation of p38 MAPK, consequently downregulated p53 and alleviated G2/M cell cycle arrest. We further showed the gate-keeping role of p53 in the lithium-induced G2/M arrest in the T2 cell line.. Our results reveal a novel mechanism underlying the differential response of the transformed and normal R6 to lithium-induced G2/M cell cycle arrest and delineate the multiplicity of signaling pathways dictating the cell fate in responding to cell stress signals.

Topics: Adenocarcinoma; Animals; Antimanic Agents; beta Catenin; Blotting, Western; Cell Line; Cell Line, Tumor; Colonic Neoplasms; Fibroblasts; Flow Cytometry; G2 Phase Cell Cycle Checkpoints; Humans; Lithium Chloride; MAP Kinase Signaling System; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Rats; Signal Transduction; Tumor Suppressor Protein p53

Glycogen synthase kinase 3 (GSK-3) has been regarded as a potential therapeutic target for multiple human cancers. We previously reported that suppression of GSK-3 activity with lithium chloride (LiCl) or small chemical inhibitors impaired cellular DNA synthesis and reduced cell proliferation in prostate cancer cells. Therefore, in this study, we extended this in vitro findings to in vivo settings in order to establish a proof of concept that inhibition of GSK-3 activity is feasible in suppressing tumor growth of prostate cancer in vivo.. In this study, we used three GSK-3 inhibitors, LiCl, TDZD-8, and L803-mts, which are structurally unrelated and non-ATP competitive. Human prostate cancer cell lines PC-3 and C4-2 were used for nude mouse xenograft models. The autochthonous transgenic prostate cancer TRAMP mice were used for testing GSK-3 inhibitor's effect on tumor development. Anti-Ki-67 and BrdU immunohistochemistry was used to determine cell proliferation. The pE2F-TA-LUC (E2F-LUC) luciferase reporter assay and gene specific small interferencing RNA technique were used to examine C/EBP involvement in GSK-3 inhibitor-induced E2F-1 suppression.. Using mouse xenograft models, we demonstrated that LiCl and TDZD-8 significantly suppressed tumor development and growth of subcutaneous xenografts derived from human prostate cancer cells. Similarly, in the TRAMP mice, TDZD-8 and L803-mts reduced the incidence and tumor burden in the prostate lobes. Consistent with our previous in vitro findings, GSK-3 inhibitors significantly reduced BrdU incorporation and Ki67-positive cells in xenograft tumors and mouse cancerous prostates compared to the control. Further analysis revealed that following GSK-3 inhibition, C/EBPα, a negative cell cycle regulator, was remarkably accumulated in xenograft tumors or in cultured prostate cancer cells. Meanwhile, knocking down C/EBPα expression abolished GSK-3 inhibition-induced suppression of E2F1 transactivation, suggesting that C/EBPα accumulation is involved in GSK-3 inhibition-induced anti-tumor effect.. Taken together, these results suggest that GSK-3 inhibition has the potential as a therapeutic strategy for prostate cancer intervention, although further pre-clinical and clinical testing are desirable.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; CCAAT-Enhancer-Binding Protein-alpha; Cell Line, Tumor; Cell Proliferation; Glycogen Synthase Kinase 3; Humans; Lithium Chloride; Male; Mice; Mice, Inbred C57BL; Mice, Nude; Mice, Transgenic; Oligopeptides; Prostatic Neoplasms; RNA, Small Interfering; Thiadiazoles

ZM336372 is small molecule tyrosine kinase modulator. It has been shown to inhibit glycogen synthase kinase-3beta (GSK-3beta) through phosphorylation of GSK-3beta at Ser 9. GSK-3beta has previously been shown to mediate cell survival in pancreatic cancer cells. Here we determine the effects of ZM336372 on GSK-3beta phosphorylation, apoptosis, and growth in pancreatic adenocarcinoma cell lines.. Panc-1 and MiaPaCa-2 cells were treated with ZM336372 or lithium chloride (LiCl) and compared with solvent control. The effects on proliferation for each cell line were determined using the MTT assay. Western blot analysis was performed to examine the effects of treatment on the phosphorylation of GSK-3beta. In addition, western blot was utilized to examine the cleavage of poly (ADP-ribose) polymerase (PARP), a marker of apoptosis.. A dose-dependent increase in phosphorylation of GSK-3beta was observed after treatment with both ZM336372 and LiCl. Growth inhibition due to treatment with ZM336372 and LiCl also occurred in a dose-dependent fashion. An increase in cleaved PARP was demonstrated after treatment with both agents, as was seen previously with GSK-3beta inhibition in pancreatic adenocarcinoma cells.. This is the first description of growth inhibition and apoptosis in pancreatic cancer cells related to GSK-3beta inhibition through treatment with ZM336372.

Topics: Adenocarcinoma; Apoptosis; Benzamides; Cell Line, Tumor; Cell Proliferation; Drug Evaluation, Preclinical; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Lithium Chloride; Pancreatic Neoplasms; Phosphorylation; Poly(ADP-ribose) Polymerases

PRL-3 is a key gene associated with progression and metastasis of colorectal cancer. Recently PRL-3 was suggested to promote epithelial mesenchymal transition (EMT) by downregulating E-cadherin expression. But the mechanisms of EMT induced by PRL-3 remain largely unknown. Here we found that PRL-3 could also promote EMT in a colorectal cancer cell model SW480 with deficient E-cadherin expression in vivo and in vitro. PRL-3 stable overexpression or knockdown SW480 cells were injected subcutaneously into nude mice. Immunohistochemical analyses of tumor samples from nude mice showed that PRL-3 promoted upregulation of mesenchymal marker vimentin and downregulation of epithelial markers E-cadherin and cytokeratin. Glycogen synthase kinase-3beta inactivated by PRL-3 as assessed by phosphospecific antibodies was a key event in EMT induced by PRL-3. Inhibition of glycogen synthase kinase-3beta by lithium chloride, a highly selective inhibitor, leading to phosphorylation of glycogen synthase kinase-3beta increased Snail expression. In order to identify the direct effects of PRL-3, we isolated CDH22, one member of cadherin family, as a new candidate of interacting proteins of PRL-3 in yeast two-hybrid systems, and the interaction was confirmed in vitro by GST pull-down assay or in exogenous cell systems and endogenous colorectal cancer cells by co-immunoprecipitation assay and co-localization analysis. We observed that PRL-3 promoted downregulation of CDH22 expression. Interestingly, expression of E-cadherin was recovered in SW480 cells after PRL-3 was knocked-down. Our results first linked PRL-3 to cadherin directly. It provided new insights into the regulatory mechanisms of EMT induced by PRL-3.

Topics: Adenocarcinoma; Animals; Cadherins; Cell Adhesion; Cell Line, Tumor; Cell Transdifferentiation; Colonic Neoplasms; Epithelial Cells; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Glycogen Synthase Kinase 3; Glycogen Synthase Kinase 3 beta; Humans; Lithium Chloride; Mesoderm; Mice; Mice, Nude; Neoplasm Proteins; Protein Interaction Mapping; Protein Tyrosine Phosphatases; Snail Family Transcription Factors; Transcription Factors

Addition of the cholinergic agents acetylcholine or carbamylcholine (CCh) to suspensions of human endometrial adenocarcinoma cells (Ishikawa line) preincubated with [3H] myoinositol promoted a rapid concentration-dependent hydrolysis of labeled phosphoinositides to inositol tris-, bis-, and monophosphates with EC50 values (mean +/- SE) of 3.5 +/- 1.6 and 26.5 +/- 4.8 microM, respectively. Atropine inhibition of the CCh effects (Ki = 1.6 +/- 1.3 nM) and the ineffectiveness of nicotinic antagonists indicate involvement of a muscarinic receptor. Both basal and CCh-stimulated production of inositol phosphates were higher in the presence of LiCl. The effect of LiCl on inositol monophosphate accumulation was concentration dependent (1-100 mM). Vasopressin, oxytocin, phenylephrine, histamine, and prostaglandin F2 alpha, had no apparent affect on inositol phosphate levels. Phorbol esters inhibited up to 35% of the effect of CCh on inositol phosphate accumulation. Triphenylethylene antiestrogens at micromolar concentrations increased inositol phosphate accumulation, but inhibited the effects of CCh. However, the rapid uptake of trypan blue observed after exposure to 10 microM tamoxifen suggests an alteration of the plasma membrane which may affect signal-transducing systems. The effects of CCh on the production of inositol phosphates and the expected concomitant liberation of diacylglycerol by transformed epithelial cells of human endometrium are of potential significance in normal endometrial physiology, since cholinergic innervation of endometrial glands has been reported, and the role of hormonally stimulated phosphoinositide hydrolysis in secretory mechanisms has been demonstrated in many systems.

Topics: Acetylcholine; Adenocarcinoma; Atropine; Carbachol; Cell Differentiation; Chlorides; Endometrium; Female; Humans; Hydrolysis; Inositol; Inositol Phosphates; Kinetics; Lithium; Lithium Chloride; Phorbol Esters; Phosphatidylinositols; Receptors, Muscarinic; Tamoxifen; Tumor Cells, Cultured; Uterine Neoplasms