scholarly journals Overexpression of the regulatory subunit of γ-glutamylcysteine synthetase in HeLa cells increases γ-glutamylcysteine synthetase activity and confers drug resistance

1999 ◽  
Vol 337 (3) ◽  
pp. 559-566 ◽  
Author(s):  
Sarah R. TIPNIS ◽  
David G. BLAKE ◽  
A.Graeme SHEPHERD ◽  
Lesley I. McLELLAN

γ-Glutamylcysteine synthetase (GCS) is reported to catalyse the rate-limiting step in glutathione biosynthesis, and is a heterodimer composed of a catalytic subunit [heavy subunit (GCSh) of Mr 73000] and a regulatory subunit [light subunit (GCSl) of Mr 31000]. In the present study, we have demonstrated for the first time a potential role for GCSl in resistance towards doxorubicin and cadmium chloride. Addition of recombinant GCSl to HeLa cell extracts in vitro was found to result in an increase in GCS activity of between 2- and 3-fold. Transient transfections of COS-1 cells with the GCSl cDNA cause an increase in GCS activity of approx. 2-fold, and a small but significant (P = 0.008) increase in glutathione levels from 126.9±4.2 nmol/mg protein to 178.8±19.1 nmol/mg protein. We proceeded to make a HeLa cell line (LN73), which stably overexpresses GCSl. These cells overexpress GCSl approx. 20-fold above basal levels. LN73 was found to have a 2-fold increase in GCS activity (437.3±85.2 pmol/min per mg) relative to the control cell line, HL9 (213.4±71.8 pmol/min per mg). In contrast with the transient transfections in COS-1 cells, stable overexpression of GCSl was found not to be associated with an increase in glutathione content. However, when the LN73 and HL9 cells were treated with the glutathione-depleting agent, diethylmaleate, the LN73 cells were found to have an enhanced ability to regenerate glutathione, compared with HL9 cells. The cell lines were treated with various anti-cancer drugs, and their cytotoxicity was examined. No obvious differences in toxicity were observed between the different cell lines following treatment with cisplatin and melphalan. The redox-cycling agent doxorubicin, however, was found to be more toxic (approx. 2-fold) to the HL9 cells than the LN73 cells. When the cells were treated with the carcinogenic transition-metal compound, cadmium chloride, LN73 cells were found to be approx. 3-fold more resistant than HL9 cells.

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Skye Hsin-Hsien Yeh ◽  
Chien-Feng Lin ◽  
Fan-Lin Kong ◽  
Hsin-Ell Wang ◽  
Ya-Ju Hsieh ◽  
...  

Mutations in the kinase domain of epidermal growth factor receptor (EGFR) have high levels of basal receptor phosphorylation and are associated with clinical responsiveness to Iressa in patients with nonsmall cell lung cancer (NSCLC). This study aimed to assess the feasibility of morpholino-[124I]IPQA derivative as anin vivoPET imaging tool for the expression of different EGFR mutants in NSCLC.In vitroradiotracer accumulation and washout studies demonstrated a rapid accumulation and progressive retention after washout of morpholino-[131I]IPQA derivative in high EGFR-expressing H1299 NSCLC derivative cell lines (L858R and E746-A750 del cell lines), but not in EGFR-transfected H1299 cell line and vector-transfected H1299 cell line. Using the morpholino-[124I]IPQA derivative, we obtained noninvasive microPET images of EGFR activity in L858R and E746-A750 del subcutaneous tumor xenografts, but not in subcutaneous tumor xenografts grown form control cell line. Different EGFR mutant (activity) tumors have a different morpholino-[∗I]IPQA derivative uptake. However, it still needs to modify the structure of IPQA to increase its water solubility and reduce hepatobiliary clearance. Morpholino-[124I]IPQA derivative may be a potential probe for selection of the candidate patients suffering from NSCLC for the small molecule tyrosine kinase inhibitor therapy (e.g., Iressa) in the future.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Julian Trah ◽  
Jonas Arand ◽  
Jun Oh ◽  
Laia Pagerols-Raluy ◽  
Magdalena Trochimiuk ◽  
...  

AbstractLithocholic bile acid (LCA) has been reported to selectively kill cancer cells within many tumor cell lines including neuroblastoma or glioblastoma. Wilms’ tumor shares similarities with neuro- and glioblastoma. Hence, the aim of the study was to evaluate the effects of LCA on nephroblastoma. To test the effects of LCA, nephroblastoma cell line WT CLS1 was used. SK NEP1 was tested as well. It was originally classified as a nephroblastoma cell line but was meanwhile reclassified as an ewing sarcoma cell line. As control cell lines HEK 293 from embryonic kidney and RC 124 from adult kidney tissue as well as podocytes were used. The effects were evaluated using proliferation assay, caspase activity assay, FACS and Western blot. LCA showed a dose and time-dependent selective effect inducing apoptosis in nephroblastoma cells. However, these effects were not limited to the nephroblastoma cell line but also affected control kidney cell lines and the sarcoma cells; only podocytes are significantly less affected by LCA (at dosages < 200 µm). There were no significant differences regarding the TGR5 receptor expression. The study showed that LCA has a strong, yet unselective effect on all used in vitro cell-lines, sparing the highly differentiated podocytes in lower concentrations. Further studies are needed to verify our results before dismissing LCA as an anti-cancer drug.


2019 ◽  
Vol 23 (07n08) ◽  
pp. 908-915 ◽  
Author(s):  
Fatma Yurt ◽  
Kasim Ocakoglu ◽  
Ozge Er ◽  
Hale Melis Soylu ◽  
Mine Ince ◽  
...  

This study, subphthalocyanines (SubPc) and SubPc integrated TiO2 nanoparticles (SubPc-TiO[Formula: see text] were synthesized as novel photosensitizers. Their PDT effects were evaluated. Furthermore, nuclear imaging potential of [Formula: see text]I-labelled SubPc/SubPc-TiO2 were examined in mouse mammary carcinoma (EMT6) and cervix adenocarcinoma (HeLa) cell lines. The uptake results show that SubPc labelled with [Formula: see text]I radionuclide ([Formula: see text]I-SubPc) in EMT6 and HeLa cell lines was found to be approximately the same as in the WI38 cell line. However, the uptake values of SubPc-TiO2 labelled with [Formula: see text]I ([Formula: see text]I-SubPc-TiO[Formula: see text] in EMT6 and HeLa cell lines were determined to be two times higher than in the WI38 cell line. In other words, the target/non-target tissue ratio was identified as two in the EMT6 and HeLa cell lines. [Formula: see text]I-SubPc-TiO2 is promising for imaging or treatment of breast and cervix tumors. In vitro photodynamic therapy studies have shown that SubPc and SubPc-TiO2 are suitable agents for PDT. In addition, SubPc-TiO2 has higher phototoxicity than SubPc. As a future study, in vivo experiments will be held and performed in tumor-bearing nude mice.


1996 ◽  
Vol 16 (4) ◽  
pp. 273-288 ◽  
Author(s):  
Jean-Bernard Dietrich

The AR4-2J cell line is derived from a transplantable tumour of the exocrine rat pancreas. Acinar in origin, this cell line contains significant amounts of amylase and can be grown in continuous culture. Many in vitro studies have been done using these cells; these studies were often complemented with in vivo experiments on animals. Particularly, many polypeptide hormones interacting with specific receptors located on the cell membrane have been analysed. The accurate knowledge of the hormone-receptor interactions has allowed to design interesting analogs of these hormones. In several cases, these compounds are powerful antagonists and are able to control cell proliferation induced by the corresponding polypeptide hormones. Other cell lines are useful to understand human pancreatic cancer. These human cell lines (Capan-1, Panc-1 for example) are of ductal origin and differ from AR4-2J cells, especially regarding the distribution of several polypeptide hormone and growth factor receptors. Both models are important for basic studies of neuropeptides, gastrointestinal peptides and their receptors, as well as for a better understanding of the underlying mechanisms of human pancreatic cancer.


2019 ◽  
Vol 7 (4) ◽  
pp. 91-96
Author(s):  
Isra'a Al-sobhi ◽  
◽  
Rawan Al-Ghabban ◽  
Soad Shaker Ali ◽  
Jehan Al-Amri ◽  
...  

2017 ◽  
Vol 63 (1) ◽  
pp. 141-145
Author(s):  
Yuliya Khochenkova ◽  
Eliso Solomko ◽  
Oksana Ryabaya ◽  
Yevgeniya Stepanova ◽  
Dmitriy Khochenkov

The discovery for effective combinations of anticancer drugs for treatment for breast cancer is the actual problem in the experimental chemotherapy. In this paper we conducted a study of antitumor effect of the combination of sunitinib and bortezomib against MDA-MB-231 and SKBR-3 breast cancer cell lines in vitro. We found that bortezomib in non-toxic concentrations can potentiate the antitumor activity of sunitinib. MDA-MB-231 cell line has showed great sensitivity to the combination of bortezomib and sunitinib in vitro. Bortezomib and sunitinib caused reduced expression of receptor tyrosine kinases VEGFR1, VEGFR2, PDGFRa, PDGFRß and c-Kit on HER2- and HER2+ breast cancer cell lines


2020 ◽  
Vol 21 (1) ◽  
pp. 42-60
Author(s):  
Farah Nawaz ◽  
Ozair Alam ◽  
Ahmad Perwez ◽  
Moshahid A. Rizvi ◽  
Mohd. Javed Naim ◽  
...  

Background: The Epidermal Growth Factor Receptor (known as EGFR) induces cell differentiation and proliferation upon activation through the binding of its ligands. Since EGFR is thought to be involved in the development of cancer, the identification of new target inhibitors is the most viable approach, which recently gained momentum as a potential anticancer therapy. Objective: To assess various pyrazole linked pyrazoline derivatives with carbothioamide for EGFR kinase inhibitory as well as anti-proliferative activity against human cancer cell lines viz. A549 (non-small cell lung tumor), MCF-7 (breast cancer cell line), SiHa (cancerous tissues of the cervix uteri), and HCT-116 (colon cancer cell line). Methods: In vitro EGFR kinase assay, in vitro MTT assay, Lactate dehydrogenase release, nuclear staining (DAPI), and flow cytometry cell analysis. Results: Compounds 6h and 6j inhibited EGFR kinase at concentrations of 1.66μM and 1.9μM, respectively. Furthermore, compounds 6h and 6j showed the most potent anti-proliferative results against the A549 KRAS mutation cell line (IC50 = 9.3 & 10.2μM). Through DAPI staining and phase contrast microscopy, it was established that compounds 6h and 6j also induced apoptotic activity in A549 cells. This activity was further confirmed by FACS using Annexin-V-FITC and Propidium Iodide (PI) labeling. Molecular docking studies performed on 6h and 6j suggested that the compounds can bind to the hinge region of ATP binding site of EGFR tyrosine kinase in a similar pose as that of the standard drug gefitinib. Conclusion: The potential anticancer activity of compounds 6h and 6j was confirmed and need further exploration in cancer cell lines of different tissue origin and signaling pathways, as well as in animal models of cancer development.


1993 ◽  
Vol 21 (2) ◽  
pp. 206-209
Author(s):  
Anders H. G. Andrén ◽  
Anders P. Wieslander

Cytotoxicity, measured as inhibition of cell growth of cultured cell lines, is a widely used method for testing the safety of biomaterials and chemicals. One major technical disadvantage with this method is the continuous routine maintenance of the cell lines. We decided to investigate the possibility of storing stock cultures of fibroblasts (L-929) in an ordinary refrigerator as a means of reducing the routine workload. Stock cultures of the mouse fibroblast cell line L-929 were prepared in plastic vials with Eagle's minimum essential medium. The vials were stored in a refrigerator at 4–10°C for periods of 7–31 days. The condition of the cells after storage was determined as cell viability, cell growth and the toxic response to acrylamide, measured as cell growth inhibition. We found that the L-929 cell line can be stored for 2–3, weeks with a viabilty > 90% and a cell growth of about 95%, compared to L-929 cells grown and subcultured in the normal manner. The results also show that the toxic response to acrylamide, using refrigerator stored L-929 cells, corresponds to that of control L-929 cells. We concluded that it is possible to store L-929 cells in a refrigerator for periods of up to 3 weeks and still use the cells for in vitro cytotoxic assays.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Parisa Taherzadeh-Soureshjani ◽  
Mohammad Chehelgerdi

Abstract Background Breast cancer (BC), as the most widely recognized disease in women worldwide, represents about 30% of all cancers impacting women. This study was aimed to synthesize Cu2O nanoparticles from the cystoseira myrica algae (CM-Cu2O NPs) assess their antimicrobial activity against pathogenic bacteria and fungi. We evaluated the expression levels of lncRNAs (MALAT1 and GAS5) and apoptosis genes (p53, p27, bax, bcl2 and caspase3), their prognostic roles. Methods In this study, CM-Cu2O NPs synthesized by cystoseira myrica algae extraction used to evaluate its cytotoxicity and apoptotic properties on MDA-MB-231, SKBR3 and T-47D BC cell lines compared to HDF control cell line. The CM-Cu2O NPs was characterized by UV–Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM). The antimicrobial activity of CM-Cu2O NPs was assessed against pathogenic bacteria, staphylococcus aureus (S. aureus) PTCC 1112 bacteria as a standard gram-positive bacteria and pseudomonas aeruginosa (P. aeruginosa) PTCC 1310 as a standard gram-negative bacterium. Expression profile of MALAT1 and GAS5 lncRNAs and apoptosis genes, i.e., p27, bax, bcl2 and caspase3 genes, were calculated utilizing qRT-PCR. The changes in the expression levels were determined using the DDCT method. Results MALAT1 was upregulated in MDA-MB-231, SKBR3 and T-47D BC (p < 0.01), while GAS5 was downregulated in SKBR3 and T-47D cell lines tested compared with HDF control cell line (p < 0.05) was found. The results revealed that, p27, bax and caspase3 were significantly upregulated in BC cell lines as compared with normal cell line. Bcl2 expression was also significantly increased in MDA-MB-231 and T47D cell lines compared with normal cell line, but bcl2 levels were downregulated in SKBR3 cell line. Conclusions Our results confirm the beneficial cytotoxic effects of green-synthesized CM-Cu2O NPs on BC cell lines. This nanoparticle decreased angiogenesis and induces apoptosis, so we conclude that CM-Cu2O NPs can be used as a supplemental drug in cancer treatments. Significantly, elevated circulating lncRNAs were demonstrated to be BC specific and could differentiate BC cell lines from the normal cell lines. It was demonstrated that lncRNAs used in this study and their expression profiles can be created as biomarkers for early diagnosis and prognosis of BC. Further studies utilizing patients would give recognizable identification of lncRNAs as key players in intercellular interactions.


1983 ◽  
Vol 96 (1) ◽  
pp. 37-50 ◽  
Author(s):  
E Schmid ◽  
DL Schiller ◽  
C Grund ◽  
J Stadler ◽  
WW Franke

Different clonal cell lines have been isolated from cultures of mammary gland epithelium of lactating cow's udder and have been grown in culture media containing high concentrations of hydrocortisone, insulin, and prolactin. These cell (BMGE+H), which grow in monolayers of typical epithelial appearance, are not tightly packed, but leave intercellular spaces spanned by desmosomal bridges. The cells contain extended arrays of cytokeratin fibrils, arranged in bundles attached to desmosomes. Gel electophoresis show that they synthesize cytokeratins similar, if not identical, to those found in bovine epidermis and udder, including two large (mol wt 58,500 and 59,000) and basic (pH range: 7-8) and two small (mol wt 45,500 and 50,000) and acidic (pH 5.32 and 5.36) components that also occur in phosphorylated forms. Two further cytokeratins of mol wts 44,000 (approximately pH 5.7) and 53,000 (pH 6.3) are detected as minor cytokeratins in some cell clones. BMGE+H cells do not produce vimentin filaments as determined by immunofluorescence microscopy and gel electrophoresis. By contrast, BMGE-H cells, which have emerged from the same original culture but have been grown without hormones added, are not only morphologically different, but also contain vimentin filaments and a different set of cytokeratins, the most striking difference being the absence of the two acidic cytokeratins of mol wt 50,000 and 45,500. Cells of the BMGE+H line are characterized by an unusual epithelial morphology and represent the first example of a nonmalignant permanent cell line in vitro that produces cytokeratin but not vimentin filaments. The results show that (a) tissue-specific patterns of intermediate filament expression can be maintained in permanent epithelial cell lines in culture, at least under certain growth conditions; (b) loss of expression of relatively large, basic cytokeratins is not an inevitable consequence of growth of epithelial cells in vitro. Our results further show that, during culturing, different cell clones with different cytoskeletal composition can emerge from the same cell population and suggest that the presence of certain hormones may have an influence on the expression of intermediate filament proteins.


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