Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.14.14.3 (luciferase)
 38,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

TGF-beta plays an important role in regulating cell differentiation and proliferation in human cancers such as colorectal cancer. Id-1 has been identified as a marker in colorectal cancer progression. The aim of this study was to investigate the role of TGF-beta in regulating Id-1 in LoVo cells. siRNA was used to silence smad2, smad3, and p38 MAPK gene expression in Lovo cells. Interference efficiency and the role of TGF-beta on Id-1 expression were analyzed using a luciferase reporter assay, RT-PCR, and Western blotting. Cell viability was determined using the MTT assay. In this study, we demonstrated that TGF-beta1 downregulated Id-1 protein expression in LoVo cells. Smad2 and smad3 siRNA inhibited TGF-beta1-induced 4xSBE luciferase reporter activity. p38 MAPK siRNA inhibited TGF-beta1-induced 3xAP-1 luciferase reporter activity. However, the suppression of Id-1 by TGF-beta1 was recovered by smad3 siRNA but not smad2 or p38 MAPK siRNA. Moreover, TGF-beta1 stimulated cellular proliferation and p21(Waf1) protein expression, which might be mediated by suppressing Id-1 expression. In conclusion, this study demonstrated that TGF-beta1 suppressed Id-1 expression in a smad3-dependent manner in LoVo cells using RNAi technology. These results provide new insight into the mechanisms of TGF-beta function in colorectal cancer cells.
 ...
PMID:Transforming growth factor-beta suppressed Id-1 Expression in a smad3-dependent manner in LoVo cells. 1979 2

This paper reviews different techniques for analyzing the transfection efficiencies and cytotoxicities of dendriplexes-complexes of nucleic acids with dendrimers. Analysis shows that three plasmids are mainly used in transfection experiments: plasmid DNA encoding luciferase from the firefly Photinus pyralis, beta-galactosidase, or green fluorescent protein. The effective charge ratio of transfection does not directly correlate with the charge ratio obtained from gel electrophoresis, zeta-potential or ethidium bromide intercalation data. The most popular cells for transfection studies are human embryonic kidney cells (HEK293), mouse embryonic cells (NIH/3T3), SV40 transformed monkey kidney fibroblasts (COS-7) and human epithelioid cervical carcinoma cells (HeLa). Cellular uptake is estimated using fluorescently-labeled dendrimers or nucleic acids. Transfection efficiency is measured by the luciferase reporter assay for luciferase, X-Gal staining or beta-galactosidase assay for beta-galactosidase, and confocal microscopy for green fluorescent protein. Cytotoxicity is determined by the MTT test and lactate dehydrogenase assays. On the basis of the papers reviewed, a standard essential set of techniques for characterizing dendriplexes was constructed: (1) analysis of size and shape of dendriplexes in dried/frozen state by electron or atomic force microscopy; (2) analysis of charge/molar ratio of complexes by gel electrophoresis or ethidium bromide intercalation assay or zeta-potential measurement; (3) analysis of hydrodynamic diameter of dendriplexes in solution by dynamic light scattering. For the evaluation of transfection efficiency the essential techniques are (4) luciferase reporter assay, beta-galactosidase assay or green fluorescent protein microscopy, and (5) cytotoxicity by the MTT test. All these tests allow the transfection efficiencies and cytotoxicities of different kinds of dendrimers to be compared.
 ...
PMID:How to study dendriplexes II: Transfection and cytotoxicity. 1981 39

To identify the possible microRNAs (miRNAs) which target the polycystic kidney disease-2 gene (PKD2), and clarify effects of the miRNAs on PKD2. We preliminarily used bioinformatics to analyze 3'UTR (3'untranslated regions) of PKD1 and PKD2 in order to predict the potential microRNAs targeted on them. Subsequently, the stable cell lines with overexpression of microRNA-17 (miR-17) were screened, and luciferase assay combined with the mutation 3'UTR of PKD2 were performed to verify PKD2 is the target of miR-17. Moreover, RT-PCR and Western Blotting were used to determine the post-transcriptionally regulation of PKD2 by miR-17. Finally, MTT cell assays allied with PKD2 rescued strategy were employed to evaluate cell proliferation effects. Our study firstly found that the 3'UTR of PKD2 was more conservation than that of PKD1, and microRNA-17 directly targets the 3'UTR of PKD2 and post-transcriptionally repress the expression of PKD2. Moreover, our findings also demonstrated that overexpression of miR-17 may promote cell proliferation via post-transcriptionally repression of PKD2 in HEK 293T. This suggested that microRNA might be a novel mechanism for cystogenesis as well as a potential therapeutic target for the cell proliferation of autosomal dominant polycystic kidney disease (ADPKD).
 ...
PMID:MicroRNA-17 post-transcriptionally regulates polycystic kidney disease-2 gene and promotes cell proliferation. 1982 Oct 56

Scatter factor (SF) and its receptor c-Met are overexpressed in various tumor types, and their expression often correlates with a poor prognosis. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), is a proposed tumor-specific chemotherapy agent, but its clinical usage is limited by acquisition of TRAIL resistance by tumors. The goals of this study were to determine whether and how SF protects tumor cells against TRAIL and whether SF-induced TRAIL resistance could be reversed. We used MTT assays, trypan blue dye exclusion assays, apoptosis assays, RNA interference, luciferase reporter assays, immunoprecipitation/western blotting, and other cell biological techniques to study SF protection of cultured human tumor cells against TRAIL. SF conferred resistance to TRAIL in various human prostate carcinoma and breast carcinoma cell lines. SF inhibited TRAIL-induced caspase-3 activation, poly (ADP-ribose) polymerase cleavage, and cell death. SF protection against TRAIL required c-Akt; but unlike protection against adriamycin, it did not require Src signaling or the classical pathway of nuclear factor-kappaB activation. Protection against TRAIL was blocked by knockdown of X-linked inhibitor of apoptosis or FLICE-inhibitor protein (FLIP) (a component of the death-inducing signaling complex). We found that c-Met physically associates with several TRAIL receptors and SF regulates their protein stability. Protection against TRAIL was blocked by a novel small molecule inhibitor of c-Met (PHA665752) and by an inhibitor of cyclooxygenase 2. In conclusion, these findings elucidate potential mechanisms of TRAIL resistance in tumors that overexpress the SF/c-Met and identify possible means of reversing this resistance.
 ...
PMID:Scatter factor protects tumor cells against apoptosis caused by TRAIL. 1982 77

Cisplatin is one of the most potent chemotherapeutic anticancer drugs for the treatment of various cancers. The cytotoxic action of the drug is often thought to be associated with its ability to bind DNA to form cisplatin-DNA adducts. Impaired DNA repair processes including base excision repair (BER) play important roles on its cytotoxicity. XRCC1 is a key protein known to play a central role at an early stage in the BER pathway. However, whether XRCC1 contributes to decrease the cisplatin cytotoxicity and cisplatin-induced DNA damage in HepG2 still remains unknown. Hence, the purpose of this study was to explore whether abrogation of XRCC1 gene expression by short hairpin RNAs (shRNA) could reduce DNA repair and thus sensitize liver cancer cells to cisplatin. We abrogated the XRCC1 gene in HepG2 cell using shRNA transfection. Cell viability was measured by MTT assay and clonogenicity assay. Comet assay was used to detect the DNA damage induced by cisplatin. The host cell reactivation was employed to assess the DNA repair capacity of cisplatin-damaged luciferase reporter plasmid. Flow cytometry analysis was used to determine cisplatin-induced apoptosis, cell cycle and reactive oxygen species (ROS). The results showed that abrogation of XRCC1 could sensitize HepG2 cells to cisplatin. This enhanced cytotoxicity could be attributed to the increased DNA damage and reduced DNA repair capacity. Increasing cell cycle arrest and intracellular ROS production lead to more tumor cell apoptosis and then enhanced the cisplatin cytotoxicity. Our results suggested that the cisplatin cytotoxicity may increase by targeting inhibition of XRCC1.
 ...
PMID:Increase the cisplatin cytotoxicity and cisplatin-induced DNA damage in HepG2 cells by XRCC1 abrogation related mechanisms. 1985 26

Leber's hereditary optic neuropathy (LHON) is a maternally inherited blinding disease due to mitochondrial DNA (mtDNA) point mutations in complex I subunit genes, whose incomplete penetrance has been attributed to both genetic and environmental factors. Indeed, the mtDNA background defined as haplogroup J is known to increase the penetrance of the 11778/ND4 and 14484/ND6 mutations. Recently it was also documented that the professional exposure to n-hexane might act as an exogenous trigger for LHON. Therefore, we here investigate the effect of the n-hexane neurotoxic metabolite 2,5-hexanedione (2,5-HD) on cell viability and mitochondrial function of different cell models (cybrids and fibroblasts) carrying the LHON mutations on different mtDNA haplogroups. The viability of control and LHON cybrids and fibroblasts, whose mtDNAs were completely sequenced, was assessed using the MTT assay. Mitochondrial ATP synthesis rate driven by complex I substrates was determined with the luciferine/luciferase method. Incubation with 2,5-HD caused the maximal loss of viability in control and LHON cells. The toxic effect of this compound was similar in control cells irrespective of the mtDNA background. On the contrary, sensitivity to 2,5-HD induced cell death was greatly increased in LHON cells carrying the 11778/ND4 or the 14484/ND6 mutation on haplogroup J, whereas the 11778/ND4 mutation in association with haplogroups U and H significantly improved cell survival. The 11778/ND4 mutation on haplogroup U was also more resistant to inhibition of complex I dependent ATP synthesis by 2,5-HD. In conclusion, this study shows that mtDNA haplogroups modulate the response of LHON cells to 2,5-HD. In particular, haplogroup J makes cells more sensitive to its toxic effect. This is the first evidence that an mtDNA background plays a role by interacting with an environmental factor and that 2,5-HD may be a risk element for visual loss in LHON. This proof of principle has broad implications for other neurodegenerative disorders such as Parkinson's disease.
 ...
PMID:The background of mitochondrial DNA haplogroup J increases the sensitivity of Leber's hereditary optic neuropathy cells to 2,5-hexanedione toxicity. 1993 68

The lipopolysaccharide (LPS)-Toll-like receptor 4 (TLR4) signaling pathway in alveolar epithelial cells plays an important role in many pathologic processes such as acute lung injury (ALI). The single immunoglobulin IL-1 receptor-related protein (SIGIRR) is an inhibitor of LPS-TLR4 signaling, but its expression and function in alveolar epithelial cells are still unknown. In this study, we examined the expression of SIGIRR in normal human lung tissue using immunohistochemistry, reverse transcription-PCR (RT-PCR) and Western blot and found that SIGIRR was expressed in alveolar epithelial cells. Treatment of an alveolar epithelial cell line, A549, with LPS and we observed a downregulation of SIGIRR mRNA, which returned to normal levels 24h after LPS exposure. A549 cells were then transfected with a SIGIRR eukaryotic expression vector to over-express SIGIRR or, as a control, with an empty vector. Following LPS exposure, the transcriptional activity of NF-kappaB was measured using a dual-luciferase reporter assay system, and the concentration of IL-1beta, TNF-alpha and IL-6 was determined by ELISA, and cell proliferation was measured by MTT. In A549 cells that over-expressed SIGIRR, LPS treatment resulted in a significant decrease in the transcriptional activity of NF-kappaB and cell growth inhibition ratio, as well as lower levels of secreted IL-1beta, TNF-alpha and IL-6. In conclusion, SIGIRR in A549 cells inhibits the transcriptional activity of NF-kappaB and reduces the amount cytokines produced, protecting these cells from acute LPS-induced damage.
 ...
PMID:Single immunoglobulin IL-1 receptor-related protein attenuates the lipopolysaccharide-induced inflammatory response in A549 cells. 1994 60

MicroRNAs (miRNAs) are endogenous small noncoding RNA molecules involved in modulation of cellular sensitivity to anti-cancer drugs. miRNA-21 (miR-21), one of the most prominent miRNAs in the genesis and progression of many human cancers, has been rarely characterized in myelogenous leukemia. Arsenic trioxide (ATO) was successfully used in the treatment of acute promyelocytic leukemia (APL) etc. However, cytotoxicity or insensitivity is a major concern in the successful treatment of leukemia. Here, we used a specific precursor miRNA-21 (pre-miR-21) or anti-miRNA-21 oligonucleotide (AMO-miR-21) to study sensitivity of HL60 and K562 cells to ATO. Cell viability and cell cycle were evaluated by MTT assay and PI assay using flow cytometry, respectively. Levels of miR-21 and its target PDCD4 were quantified by real-time PCR and/or western blot. AMO-miR-21 or ATO alone led to growth inhibition, apoptosis and G1 phase arrest of cell cycle. Apoptotic cells were confirmed morphologically with Hoechst staining. Moreover, there was somewhat synergistic effect of AMO-miR-21 and ATO in growth inhibition and apoptosis promotion. Meanwhile, enforced pre-miR-21 expression increased resistance to ATO, nevertheless not affecting cell growth alone. Dual-luciferase reporter vector containing two tandem PDCD4 3' UTR validated that PDCD4 was directly up-regulated by miR-21. Therefore, miRNA-21 by targeting PDCD4 may play a functional role in modulating ATO-induced cell death, and strategy using AMO-miR-21 and its combination with ATO may be useful as a myelogenous leukemia therapy.
 ...
PMID:miRNA-21 regulates arsenic-induced anti-leukemia activity in myelogenous cell lines. 2014 88

Magnetic nonviral gene vectors were in situ prepared in the presence of ferrous salts and hyperbranched poly(ethylenimine)s (HPEI) with different molecular weights. HPEI, one of the most promising nonviral vectors, was not only utilized as the nanoreactor and stabilizer to prepare magnetic nanoparticles, but also skillfully used as a base supplier to avoid introducing alkali hydroxide or ammonia. Magnetic nonviral gene vectors with various magnetite contents and saturation magnetizations were obtained by changing the weight ratio of HPEI to FeSO(4).7H(2)O and the molecular weight of HPEI. MTT assays suggested that the resulting magnetite/HPEI gene vectors had lower cytotoxicity compared with pure HPEI. The magnetite/HPEI nonviral gene vectors were used for magnetofection. It was found that the luciferase expression level mediated by magnetite/HPEI in COS-7 cells under a magnetic gradient field was approximately 13-fold greater than that of standard HPEI transfection.
 ...
PMID:In situ preparation of magnetic nonviral gene vectors and magnetofection in vitro. 2017 30

The transcription factor NRF2 defends the cell from oxidative stress by up-regulating a large number of antioxidant genes through its binding with antioxidant response element on gene promoters. Cancer cells are known to possess high levels of antioxidant genes that increases survival in cancer microenvironment of oxidative stress, particularly in the treatment with anticancer agents. In the current study we have examined the role of the NRF2 in doxorubicin sensitivity and tumor growth by establishing stable cell line expressing NRF2 shRNA in the human ovarian carcinoma cell line OV90. On knockdown of NRF2 through NRF2-specific shNRF2 expressing lentiviral plasmid, antioxidant response element-driven luciferase activity as well as the expression of NRF2-target genes were significantly suppressed compared to nonspecific scrambled RNA (scRNA) expressing cells. In addition, shNRF2 expressing OV90-shNRF2 cells showed a reduction in total GSH levels by 82% and cell growth was observed to be significantly retarded compared to scRNA control cells. Furthermore, stable inhibition of NRF2 sensitized OV90 cells were seen following doxorubicin treatment as shown by the analysis with MTT assay and propidium iodide-fluorescence-activated cell sorting. OV90-shNRF2 cells showed higher levels of cell death and apoptosis in response to doxorubicin than OV90-scRNA cells. While, when BALBc (nu/nu) mice with OV90 tumor xenograft in the flanks were injected with NRF2 shRNA containing viral particles and treated with doxorubicin a pattern of retardation in tumor growth was seen in shRNA group compared to scRNA group, but this difference was not statistically significant. In conclusion, we propose that the NRF2 signaling might be a molecular target to repress tumor growth and enhance cytotoxic effects of anticancer agent in cancer cells.
 ...
PMID:Effect of stable inhibition of NRF2 on doxorubicin sensitivity in human ovarian carcinoma OV90 cells. 2051 70


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>