Cardiovascular Diseases ; Humans ; Membrane Proteins ; Neoplasm Proteins ; Stromal Interaction Molecule 1

Animals ; Inflammation Mediators/metabolism* ; Macrophages/metabolism* ; Mice ; Stromal Interaction Molecule 1/metabolism*

OBJECTIVETo investigate the role of store-operated calcium channels (SOCs) in primary hepatocytes under conditions of calcium overload and ethanol-induced injury.

METHODSThe in vitro model of chronic ethanol-induced hepatocyte injury was established using primary hepatocytes isolated from Sprague-Dawley rats. Ethanol-induced changes (24, 48 and 72 h; 50, 100, 200, 400 and 800 mmol/L) in expression of the SOCs proteins stromal interaction molecule 1 (STIM1) and calcium release-activated calcium channel protein 1 (Oria1) were detected by qualitative PCR analysis (mRNA) and western blotting (protein). The possible role of these two SOCs proteins in the ethanol-induced extracellular calcium influx and related liver cell injury was determined by treating the cell system with various channel blockers (EGTA, La3+, and 2-APB). Cell viability was determined by MTT assay and cytosolic free calcium ion concentration was determined by flow cytometry.

RESULTSAfter 24 h of exposure to 0 (untreated) to 800 mM/L ethanol, the cell viability was reduced in a concentration-dependent manner. The 400 mmol/L concentration of ethanol decreased cell viability by 57.34% +/- 2.34%. and was chosen for use in subsequent experiments. Compared with the untreated control cells, the ethanol-treated cells showed significantly up-regulated mRNA and protein expression of both STIM1 and Orai1 at all times examined, suggesting that the ethanol-stimulated expression of STIM1 and Orai1 could persist for at least 72 h. The ethanol treatment induced increase in cytoplasmic calcium levels was significantly (and similarly) reduced by co-treatment with any of the three channel blockers.

CONCLUSIONChronic ethanol exposure can increase the expression of STIM1 and Orai1 in primary liver cells, suggesting that ethanol may increase extracellular calcium influx by up-regulating expression of these SOCs protein molecules, ultimately aggravating liver cell damage.

Animals ; Calcium ; metabolism ; Calcium Channel Blockers ; pharmacology ; Calcium Channels ; metabolism ; Calcium-Binding Proteins ; metabolism ; Cell Survival ; Cells, Cultured ; Ethanol ; adverse effects ; Hepatocytes ; drug effects ; metabolism ; Male ; Membrane Glycoproteins ; metabolism ; Primary Cell Culture ; Rats ; Rats, Sprague-Dawley ; Stromal Interaction Molecule 1

OBJECTIVEThe purpose of this study is to explore the impact of stromal interaction molecule 1 (STIM1) knockdown on the proliferation and migration capacities of endothelial progenitor cells (EPCs).

METHODSThe rat bone marrow derived EPCs were obtained and divided into three groups: adenovirus negative control (NSC) group, rat STIM1 adenovirus vector transfection (si/rSTIM1) group and rat and human recombinant STIM1 adenovirus transfection (si/rSTIM1+hSTIM1) group. The STIM1 expressions in each group were detected by reverse transcription PCR after transfection. The cell proliferation was tested by [(3)H] thymidine incorporation assay ((3)H-TdR). Cell cycle was analyzed by flow cytometry. The cells migration activity was detected by Boyden assay. Calcium ion concentration was detected by confocal laser scanning microscopy.

RESULTS48 h after transfection, the expression level of STIM1 in si/rSTIM1 group was significantly lower than that in NSC group (0.21 ± 0.12 vs. 1.01 ± 0.01, P < 0.05), and number of EPCs at G1 phase in si/rSTIM1 group ((93.31 ± 0.24)%) was significantly higher than that in NSC group ((78.03 ± 0.34)%, P < 0.05), and EPCs' migration activity in si/rSTIM1 group (10.03 ± 0.33) was significantly lower than that in NSC group (32.11 ± 0.54, P < 0.05), and EPCs calcium ion concentration in EPCs in si/rSTIM1 group (38.03 ± 0.13) was significantly lower than that in NSC group (98.11 ± 0.34, P < 0.05), while there was no significant difference between si/rSTIM1+hSTIM1 group and NSC group on the above four indexes.

CONCLUSIONSilencing STIM1 could attenuate EPCs proliferation and migration capacities by modulating the calcium ion concentration in EPCs.

Adenoviridae ; Animals ; Cell Cycle ; Cell Division ; Cell Movement ; Cell Proliferation ; Endothelial Cells ; Endothelial Progenitor Cells ; Flow Cytometry ; Genetic Vectors ; Humans ; Membrane Proteins ; Neoplasm Proteins ; Rats ; Stromal Interaction Molecule 1 ; Transfection

Cell Transformation, Neoplastic ; drug effects ; genetics ; Dimethyl Sulfoxide ; pharmacology ; Electroporation ; methods ; HL-60 Cells ; Humans ; Membrane Proteins ; genetics ; Neoplasm Proteins ; genetics ; RNA Interference ; RNA, Small Interfering ; genetics ; Stromal Interaction Molecule 1 ; Transfection

OBJECTIVETo evaluate the inhibition effect of STIM1 gene silencing on tumor growth of human hypopharyngeal carcinoma cell lines FaDu in nude mice.

METHODSSTIM1 gene in FaDu was silenced by lentiviral infection, and the effect of inhibition was detected by Real-time PCR and Western blot after lentiviral infection. Nude mice were divided into 2 groups, 5 mice in each group. Inhibition group: subcutaneous inject FaDu cells which STIM1 expression was inhibited.

CONTROL GROUPsubcutaneous inject FaDu cells infected with negative control siRNA-expressing lentivirus. Tumor volumes were measured by calipers, and small animal imaging was detected by NightOWL system on the day 10, 14, 18 and 22 after tumor inoculated. Tumor weights were evaluated in the day 22 after tumor inoculated. Statistical analysis was performed using standard student test(P value threshold was 0.05).

RESULTSThe expressions of human STIM1 gene and protein in FaDu cells were suppressed effectively after STIM1-siRNA lentiviral infection. The mean tumor volumes of control group and inhibition group were (51±25) mm3 and (40±35) mm3, respectively, on the day 10, (262±107) and (106±41) mm3 on the day 14, (716±226) and (340±158) mm3 on the day, (1 682±592) mm3 and (917±252)mm3 on the day 22 (P<0.05). On the day 22, the tumor weight was (1.22±0.41) g in control group and (0.66±0.26) g in STIM1-siRNA group (P<0.05). Small animal imaging showed that the tumors had a smaller fluorescence range with lower signal intensity in STIM1-siRNA group than in control group on the day 14, 18 and 22.

CONCLUSIONThe expression of STIM1 in human hypopharyngeal carcinoma cell lines FaDu can be inhibited effectively by lentiviral infection, causing the inhibition of tumor formation and growth.

Animals ; Cell Line, Tumor ; Gene Silencing ; Humans ; Hypopharyngeal Neoplasms ; pathology ; Lentivirus ; Membrane Proteins ; genetics ; Mice ; Mice, Nude ; Neoplasm Proteins ; genetics ; Neoplasm Transplantation ; RNA, Small Interfering ; Real-Time Polymerase Chain Reaction ; Stromal Interaction Molecule 1

Store-operated Ca(2+) channels (SOCs) are plasma membrane Ca(2+) permeable channels activated by depletion of intracellular Ca(2+) store. Ca(2+) entry through SOCs is known as store-operated Ca(2+) entry (SOCE), which plays an important role in the functional regulation of airway smooth muscle cells (ASMCs). Protein kinase C (PKC) has been shown to have an activating or inhibiting effect on SOCE, depending on cell types and PKC isoforms that are involved. In ASMCs, the effect of PKC on SOCE has not been elucidated so far. In this study, the role of PKC in the activation of SOCE in rat ASMCs was examined by using Ca(2+) fluorescence imaging technique. The results showed that acute application of PKC activators PMA and PDBu did not affect SOCE induced by the sarcoplasmic reticulum Ca(2+)-ATPase (SERCA) inhibitor thapsigargin. The non-selective PKC inhibitor chelerythrine significantly inhibited thapsigargin- and bradykinin-induced SOCE. RT-PCR assay identified PKCα, δ and ɛ isoforms in rat ASMCs. PKCα-selective inhibitor Gö6976 and PKCɛ-inhibiting peptide Epsilon-V1-2 had no effect on SOCE; by contrast, PKCδ-selective inhibitor rottlerin attenuated SOCE dramatically, suggesting that PKCδ was the major PKC isoform involved in the activation of SOCE in ASMCs. Moreover, PKC down-regulation by extended exposure to high doses of PMA or PDBu also reduced SOCE, confirming the essential role of PKC in the activation of SOCE in ASMCs. In addition, PKC down-regulation did not influence the expression of stromal interaction molecule 1 (STIM1) and Orai1, two elementary molecules in the regulation and activation of SOCs. These results identified PKCδ as an essential PKC isoform involved in the activation of SOCE, and confirmed that PKC regulates the function of ASMCs in a SOCE-dependent manner.
Animals ; Bronchi ; metabolism ; Calcium ; metabolism ; Calcium Channels ; Calcium Signaling ; physiology ; Cells, Cultured ; Male ; Membrane Glycoproteins ; metabolism ; Myocytes, Smooth Muscle ; metabolism ; ORAI1 Protein ; Protein Kinase C-delta ; metabolism ; Rats ; Rats, Sprague-Dawley ; Stromal Interaction Molecule 1

OBJECTIVETo investigate the effect of stromal interaction molecule 1 (STIM1) silencing on EPCs cell cycle.

METHODSRat bone marrow derived endothelial progenitor cells (EPCs) were isolated and cultured in L-DMEM with 20% FBS. Ad-si/rSTIM1 and Ad-hSTIM1 were then transfected into EPCs and the expression of STIM1 mRNA was detected by RT-PCR. The cell cycle was determined using flow cytometry analysis and intracellular free Ca2+ was measured using LSCM. Co-immunoprecipitation was performed to examine the interaction between STIM1 and TRPC1. Protein levels of inositol 1, 4, 5-trisphosphate were analyzed with ELISA assay.

RESULTSForty-eight hours after transfection, the expression of STIM1 mRNA was significantly downregulated (0.37 +/- 0.02 vs. 1.00 +/- 0.02, P < 0.05) and intracellular free Ca2+ level was significantly reduced (34.07 +/- 4.10 vs. 86.51 +/- 14.12, P < 0.05) in Ad-si/rSTIM1 group compared with control group. The cell cycle was arrested at G1 phase [(90.91 +/- 1.10)% vs. (77.10 +/- 0.56)%, P < 0.05] and the store-operated channel entry was strikingly inhibited in EPCs after treatment with Ad-si/rSTIM1. However, cotransfection of Ad-hSTIM1 with Ad-si/rSTIM1 significantly reversed these responses. Interestingly, co-immunoprecipitation study showed that STIM1 co-precipitated with TRPC1, and IP3 levels measured by ELISA were similar among three groups (P > 0.05).

CONCLUSIONsiRNA-mediated knockdown of STIM1 inhibited EPCs proliferation by reducing intracellular free Ca2+ through TRPC1-SOC signaling pathway.

Adenoviridae ; genetics ; Animals ; Cell Cycle ; Cell Proliferation ; Cells, Cultured ; Endothelial Cells ; cytology ; Gene Silencing ; Genetic Vectors ; Membrane Proteins ; genetics ; Neoplasm Proteins ; genetics ; RNA, Small Interfering ; Rats ; Stem Cells ; cytology ; Stromal Interaction Molecule 1 ; Transfection ; Transient Receptor Potential Channels ; metabolism

OBJECTIVETo investigate the mechanism underlying sodium butyrate (NaB)-induced apoptosis of a human colon cancer cell line HCT-116.

METHODSThe apoptosis of HCT-116 cells induced by NaB was confirmed by hoechst33342 staining and AnnexinV+ PI assay. The changes in the intracellular localization of stromal interaction molecule (STIM1) and Orai1 following NaB treatment were detected by immunofluorescence technique. Western blotting was used to investigate the protein expression levels of STIM1 and Orai1.

RESULTSNaB induced apoptosis and caused translocation and colocalization of STIM1 and Orai1 in HCT-116 cells.

CONCLUSIONThe apoptosis of human colon cancer cells induced by NaB is correlated to the redistribution of STIM1 and Orai1.

Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Butyrates ; pharmacology ; Calcium Channels ; metabolism ; HCT116 Cells ; Histone Deacetylase Inhibitors ; pharmacology ; Humans ; Membrane Proteins ; metabolism ; Neoplasm Proteins ; metabolism ; ORAI1 Protein ; Stromal Interaction Molecule 1

Store-operated calcium (Ca2+) entry (SOCE) is the principal Ca2+ entry route in non-excitable cells, including cancer cells. We previously demonstrated that Orai1 and STIM1, the molecular components of SOCE, are involved in tumorigenesis of clear cell renal cell carcinoma (CCRCC). However, a clinical relevance of Orai1 and STIM1 expression in CCRCC has been ill-defined. Here, we investigated the expression of Orai1 and STIM1 in CCRCC, and compared their expression with clinico-pathological parameters of CCRCC and the patients' outcome. Immunohistochemical staining for Orai1 and STIM1 was performed on 126 formalin fixed paraffin embedded tissue of CCRCC and western blot analysis for Orai1 was performed on the available fresh tissue. The results were compared with generally well-established clinicopathologic prognostic factors in CCRCC and patient survival. Membrane protein Orai1 is expressed in the nuclei in CCRCC, whereas STIM1 shows the cytosolic expression pattern in immunohistochemical staining. Orai1 expression level is inversely correlated with CCRCC tumor grade, whereas STIM1 expression level is not associated with tumor grade. The higher Orai1 expression is significantly associated with lower Fuhrman nuclear grade, pathologic T stage, and TNM stage and with favorable prognosis. The expression level of STIM1 is not correlated with CCRCC grade and clinical outcomes. Orai1 expression in CCRCC is associated with tumor progression and with favorable prognostic factors. These results suggest that Orai1 is an attractive prognostic marker and therapeutic target for CCRCC.
Adolescent ; Adult ; Aged ; Blotting, Western ; Carcinoma, Renal Cell/*diagnosis/metabolism/*pathology ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Kidney Neoplasms/metabolism/*pathology ; Male ; Middle Aged ; Neoplasm Proteins/genetics/metabolism ; ORAI1 Protein/genetics/*metabolism ; Prognosis ; Retrospective Studies ; Stromal Interaction Molecule 1/genetics/metabolism ; Young Adult