Cytotoxicity of tamoxifen in normal and tumoral cell lines and its ability to induce cellular transformation in vitro

Neuroblastoma (NB) is a neural crest-derived tumor, which develops before birth or in early childhood, with metastatic dissemination typically preceding diagnosis. Tumors are characterized by a highly heterogeneous combination of cellular phenotypes demonstrating varying degrees of differentiation along different lineage pathways, and possessing distinct super-enhancers and core regulatory circuits, thereby leading to highly varied malignant potential and divergent clinical outcomes. Cytoskeletal reorganization is fundamental to cellular transformations, including the processes of cellular differentiation and epithelial to mesenchymal transition (EMT), previously reported by our lab and others to coincide with chemotherapy resistance and enhanced metastatic ability of tumor cells. This study set out to investigate the ability of the neuronal miR-124-3p to reverse the cellular transformation associated with drug resistance development and assess the anti-oncogenic role of this miRNA in in vitro models of drug-resistant adrenergic (ADRN) and mesenchymal (MES) neuroblastoma cell lines. Low expression of miR-124-3p in a cohort of neuroblastomas was significantly associated with poor overall and progression-free patient survival. Over-expression of miR-124-3p in vitro inhibited cell viability through the promotion of cell cycle arrest and induction of apoptosis in addition to sensitizing drug-resistant cells to chemotherapeutics in a panel of morphologically distinct neuroblastoma cell lines. Finally, we describe miR-124-3p direct targeting and repression of key up-regulated cytoskeletal genes including MYH9, ACTN4 and PLEC and the reversal of the resistance-associated EMT and enhanced invasive capacity previously reported in our in vitro model (SK-N-ASCis24).

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In vitro and in vivo studies with [18F]fluorocholine on digestive tumoral cell lines and in an animal model of metastasized endocrine tumor

Nuclear Medicine and Biology ◽

10.1016/j.nucmedbio.2007.09.008 ◽

2008 ◽

Vol 35 (1) ◽

pp. 123-130 ◽

Cited By ~ 5

Author(s):

Mimoun Nejjari ◽

David Kryza ◽

Gilles Poncet ◽

Colette Roche ◽

Nathalie Perek ◽

...

Keyword(s):

Animal Model ◽

Cell Lines ◽

Endocrine Tumor ◽

In Vivo Studies ◽

Tumoral Cell

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Exogenous bacterial DnaK increases protein kinases activity in human cancer cell lines

Journal of Translational Medicine ◽

10.1186/s12967-021-02734-4 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Francesca Benedetti ◽

Sabrina Curreli ◽

Robert C. Gallo ◽

Davide Zella

Keyword(s):

Tumor Microenvironment ◽

Protein Kinases ◽

Cell Lines ◽

Cancer Cell ◽

Cancer Progression ◽

Critical Role ◽

Cellular Transformation ◽

Cancer Cell Lines ◽

Human Microbiota

Abstract Background Studies of molecular mechanisms underlying tumor cell signaling highlighted a critical role for kinases in carcinogenesis and cancer progression. To this regard, protein kinases regulates a number of critical cellular pathways by adding phosphate groups to specific substrates. For this reason, their involvement in the complex interactions between the human microbiota and cancer cells to determine therapy and tumor progression outcome is becoming increasingly relevant. Mycoplasmas are components of the normal human microbiota, and several species have also been associated to human diseases, including certain cancers. It is also important to note that Mycoplasmas and their proteins are a component of the common tumor microenvironment. In addition, several epidemiological, in vivo and in vitro studies indicate a close involvement of Mycoplasmas in cellular transformation and cancer progression. Methods In this study, we investigate the effect of exogenous Mycoplasma DnaK on kinases activity by treating in vitro four different eukaryotic cancer cell lines, namely lung and prostate cancer, colon adenocarcinoma, and neuroblastoma. Phosphorylation of kinases and specific substrates was measured at 20 and 60 min. Results Kinome analysis of our data indicates that Mycoplasma DnaK promotes the dysregulation of the activity of specific kinases and their substrates, with a known involvement in carcinogenesis and cancer progression. Conclusions Given the similarity in structure and amino acid composition of this protein with other bacterial DnaKs we provide a novel mechanism whereby components of the human microbiota and present in the tumor microenvironment are able to deregulate phosphorylation events occurring during carcinogenesis and cancer progression.

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Copaifera multijuga, Copaifera pubiflora and Copaifera trapezifolia Oleoresins: Chemical Characterization and in vitro Cytotoxic Potential against Tumoral Cell Lines

Journal of the Brazilian Chemical Society ◽

10.21577/0103-5053.20200054 ◽

2020 ◽

Author(s):

Luiza Carneiro ◽

Thercius Tasso ◽

Mario Santos ◽

Mirian Goulart ◽

Raquel dos Santos ◽

...

Keyword(s):

Cell Lines ◽

Chemical Characterization ◽

Cytotoxic Potential ◽

Tumoral Cell

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Overexpression of Jak Kinases Promotes In Vitro Transformation.

Blood ◽

10.1182/blood.v104.11.4325.4325 ◽

2004 ◽

Vol 104 (11) ◽

pp. 4325-4325

Author(s):

Laurent Knoops ◽

Yohan Royer ◽

Stefan Constantinescu ◽

Jean-Christophe Renauld

Keyword(s):

Cell Lines ◽

Cellular Transformation ◽

Hematologic Malignancies ◽

Genetic Event ◽

Multistep Process ◽

Selection Step ◽

Selection Of ◽

Stat Pathway

Abstract The Jak-STAT pathway is responsible for signal transduction by a large number of cytokine receptors. While this pathway is normally tightly regulated, constitutive STAT3 and STAT5 activation is frequent in hematologic malignancies and contributes to oncogenesis. We took advantage of the IL-3-dependent pro-B Ba/F3 cell line to analyze the mechanisms of constitutive STAT activation in vitro. Ba/F3 cells transfected with a mutated hIL-9R (Ba/F3 Phe116) poorly respond to IL-9. However, after selection with this cytokine, we obtained cell lines that proliferated well in IL-9. After cytokine withdrawal, those cells, in contrast to the parental cells, gave rise to autonomous Ba/F3 cell lines showing constitutive STAT5 activation, and that were highly tumorigenic in vivo. This process mimics the multistep process of oncogenesis occurring in vivo. To dissect the mechanisms involved in this cellular transformation, we analyzed, using cDNA microarrays, genes expressed in one of these autonomous lines. Jak1, the Jak kinase associated to the IL-9 receptor, was found to be upregulated compared to parental cells. It was the key genetic event involved in this transformation since ectopic Jak1 overexpression increased the sensitivity to IL-9 and allowed, after a second selection step, for spontaneous progression towards autonomous cell lines with constitutive STAT activation. Using Jak1 mutants, we showed that the generation of autonomous lines was dependent on the tyrosine kinase activity of Jak1 and on a functional FERM domain, the domain that mediates association with the receptor. These results were extended to the other Jak family members. Therefore, we propose that Jak overexpression can be considered as one of the oncogenic events leading to the selection of cells highly responsive to growth factors and, after a second selection step, to autonomous cells with constitutive activation of the Jak-STAT pathway. This process could be extended to human malignancies and might explain, for instance, the constitutive STAT6 activation in primary mediastinal large B cell lymphomas where Jak2 overexpression was described.

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Expression of BCR-ABL Does Not Inhibit Apoptosis In Vitro, on a B Lymphoblastoid Cell Line.

Blood ◽

10.1182/blood.v104.11.4242.4242 ◽

2004 ◽

Vol 104 (11) ◽

pp. 4242-4242

Author(s):

Fabiola A. Castro ◽

Gabriela Brumatti ◽

Gustavo P. Amarante-Mendes

Keyword(s):

Cell Lines ◽

Mrna Level ◽

Philadelphia Chromosome ◽

Ectopic Expression ◽

Cellular Transformation ◽

Lymphocytic Leukemia ◽

Myelogenous Leukemia ◽

Wild Type ◽

Protein Levels

Abstract The bcr-abl oncogene is generated by the Philadelphia chromosome (Ph) translocation, fusing the BCR gene to the ABL gene and occurs mainly in two different forms. In chronic myelogenous leukemia (CML) a 210kDa Bcr-Abl protein is associated with proliferation and accumulation of myeloid cells and their precursors, whereas a 185kDa form is responsible for the pathogenesis of acute lymphocytic leukemia (ALL). Bcr-Abl not only induces cellular transformation but also regulates cell proliferation and confers resistance to a variety of apoptosis-inducing agents. Much attention has been focused on the development of novel therapies based on mechanistic understanding of Bcr-abl signaling in CML cells. However, we still do not fully understand how this molecule interferes with apoptotic machinery. The aim of this study was to investigate which step of the apoptotic machinery was most influenced by ectopic expression of Bcr-Abl myeloblastic (HL-60) and B lymphoblastic (SKW6.4) cell lines. Ectopic expression of Bcr-Abl conferred resistance to apoptosis induced by staurosporine and anti-Fas in HL-60 cells, but not in SKW6.4 cells, although increased phosphotyrosine containing proteins could be easily observed in SKW6.4.Bcr-Abl cells. The protein levels of Bcl-xL, Mcl-1 and Flip detected by western-blot were greater in HL-60.Bcr.Abl, when compared to wild type HL-60 cells. In contrast, the proapoptotic protein Bid was considerably reduced in HL-60. Bcr-abl cells. Two independent lines of SKW6.4.Bcr-Abl cells had a small reduction of in Bid levels, but no difference was observed in the expression of the anti-apoptotic proteins Bcl-xL, Mcl-1 and Flip. At the mRNA level SKW6.4 and SKW.Bcr-Abl presented similar expression of Bcl-xL, Mcl-1 and Flip. In addition a greater expression of anti-apoptotitc proteins A1 (IDV A1/actin=0.6) and Bcl-w (IDV Bcl-w/actin=1.6) was found in SKW6.4.Bcr-Abl compare to SKW (0.2 and 0.01, respectively) wild type. Interestingly, the upregulated levels of these anti-apoptotic genes were not sufficient to prevent apoptosis in these cells. Taken together these results suggest that Bcr-abl is not capable of protecting SKW6.4 cells from apoptosis induced by staurosporine and anti-Fas, perhaps because it interacts differently with the apoptotic machinery in B lymphoblasts compared to myeloblast cell lines. Further stydies are underway in our laboratory in order to better understand the Bcr-abl-mediated anti-apoptotic signaling in B lymphoblast cells.

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