scholarly journals Ortho-substituted PCB 153: effects in CHO-K1 cells

2021 ◽  
Vol 72 (4) ◽  
pp. 326-332
Author(s):  
Marina Miletić ◽  
Teuta Murati ◽  
Branimir Šimić ◽  
Nina Bilandžić ◽  
Anamaria Brozović ◽  
...  

Abstract Non-planar di-ortho-substituted PCB 153 (2,2’,4,4’,5,5’-hexachlorobiphenyl), one of the most abundant PCB congeners in the environment and in biological and human tissues, has been identified as potential endocrine disruptor affecting the reproductive and endocrine systems in rodents, wildlife, and humans. The aim of this study was to gain a deeper insight into its mode/mechanism of action in Chinese hamster ovary K1 cells (CHO-K1). PCB 153 (10–100 μmol/L) inhibited CHO-K1 cell proliferation, which was confirmed with four bioassays (Trypan Blue, Neutral Red, Kenacid Blue, and MTT), of which the MTT assay proved the most sensitive. PCB 153 also induced ROS formation in a dose-dependent manner. Apoptosis was seen after 6 h of exposure to PCB 153 doses ≥50 μmol/L, while prolonged exposure resulted in the activation of the necrotic pathway. PCB 153-induced disturbances in normal cell cycle progression were time-dependent, with the most significant effects occurring after 72 h.

Author(s):  
M. Pacurari ◽  
H. Brown ◽  
A. Rieland

Background: Acute promyelocytic leukemia (APL) affects both kids and adults, however it is more prevalent in younger population. Although APL has a favorable prognostic, patients that relapse often do not respond positively to additional chemotherapy. Therefore, there is a need to further identify ways to overcome these challenges.  Hypothesis: In this study, we examined antileukemic effects of xanthohumol (XN), a prenylated flavonoid derived from hops (Humulus lupulus L), on human promyelocytic HL-60 cells.  Materials and Methods: HL-60 cells were exposed to different concentrations of XN (μM) for 24 h. Cell viability, cell morphology, chromatin condensation, cPARP-1 level, and caspase-3 activation, and the expression of p21WAF1/Cip1 were analyzed. Results: XN reduced HL-60 cell viability in a dose-dependent manner. XN induced a dose-dependent morphological changes including cell shrinkage and blebbing, and significantly increased the number of cells with condensed chromatin. XN significantly increased the level of cPARP-1, active caspase-3, and the expression of p21WAF/CIP mRNA. Conclusion: These data indicate that XN induces HL-60 cell death by regulating cell cycle progression and apoptosis. This study suggests that XN may have antileukemic preventive effects.


Blood ◽  
2021 ◽  
Author(s):  
Ayako Nakamura-Ishizu ◽  
Desmond Chin ◽  
Takayoshi Matsumura ◽  
Darren Qiancheng Tan ◽  
Makiko Kashio Mochizuki ◽  
...  

Hematopoietic stem cells (HSC) rarely divide, rest in quiescence and proliferate only upon stress hematopoiesis. The cytokine thrombopoietin (Thpo) has been perplexingly described to induce quiescence and promote self-renewal divisions in HSCs. In order to clarify the contradictory effect of Thpo, we conducted a detailed analysis on conventional (Thpo-/-) and liver-specific (Thpofl/fl;AlbCre+/-) Thpo deletion models. Thpo-/- HSCs exhibited profound loss of quiescence, impaired cell cycle progression and increased apoptosis. Thpo-/- HSCs also exhibited diminished mitochondrial mass and impaired mitochondrial bioenergetics. Abnormal HSC phenotypes in Thpo-/- mice were reversible after HSC transplantation into wild type recipients. Moreover, Thpo-/- HSCs acquired quiescence with extended administration of a Thpo-receptor agonist, Romiplostim, and were prone to subsequent stem cell exhaustion during competitive bone marrow (BM) transplantation. Thpofl/fl;AlbCre+/- HSCs exhibited similar stem cell phenotypes but at a lesser extent than Thpo-/- HSCs. HSCs that survive Thpo deficiency acquire quiescence in a dose-dependent manner through the modification of their metabolic state.


Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2178
Author(s):  
Fabio Morandi ◽  
Veronica Bensa ◽  
Enzo Calarco ◽  
Fabio Pastorino ◽  
Patrizia Perri ◽  
...  

Neuroblastoma (NB) is the most common extra-cranial solid tumor of pediatric age. The prognosis for high-risk NB patients remains poor, and new treatment strategies are desirable. The olive leaf extract (OLE) is constituted by phenolic compounds, whose health beneficial effects were reported. Here, the anti-tumor effects of OLE were investigated in vitro on a panel of NB cell lines in terms of (i) reduction of cell viability; (ii) inhibition of cell proliferation through cell cycle arrest; (iii) induction of apoptosis; and (iv) inhibition of cell migration. Furthermore, cytotoxicity experiments, by combining OLE with the chemotherapeutic topotecan, were also performed. OLE reduced the cell viability of NB cells in a time- and dose-dependent manner in 2D and 3D models. NB cells exposed to OLE underwent inhibition of cell proliferation, which was characterized by an arrest of the cell cycle progression in G0/G1 phase and by the accumulation of cells in the sub-G0 phase, which is peculiar of apoptotic death. This was confirmed by a dose-dependent increase of Annexin V+ cells (peculiar of apoptosis) and upregulation of caspases 3 and 7 protein levels. Moreover, OLE inhibited the migration of NB cells. Finally, the anti-tumor efficacy of the chemotherapeutic topotecan, in terms of cell viability reduction, was greatly enhanced by its combination with OLE. In conclusion, OLE has anti-tumor activity against NB by inhibiting cell proliferation and migration and by inducing apoptosis.


2015 ◽  
Vol 112 (18) ◽  
pp. 5732-5737 ◽  
Author(s):  
Ya-Lin Huang ◽  
Zeinab Anvarian ◽  
Gabriele Döderlein ◽  
Sergio P. Acebron ◽  
Christof Niehrs

DuringXenopusdevelopment, Wnt signaling is thought to function first after midblastula transition to regulate axial patterning via β-catenin–mediated transcription. Here, we report that Wnt/glycogen synthase kinase 3 (GSK3) signaling functions posttranscriptionally already in mature oocytes via Wnt/stabilization of proteins (STOP) signaling. Wnt signaling is induced in oocytes after their entry into meiotic metaphase II and declines again upon exit into interphase. Wnt signaling inhibits Gsk3 and thereby protects proteins from polyubiquitination and degradation in mature oocytes. In a protein array screen, we identify a cluster of mitotic effector proteins that are polyubiquitinated in a Gsk3-dependent manner inXenopus. Consequently inhibition of maternal Wnt/STOP signaling, but not β-catenin signaling, leads to early cleavage arrest after fertilization. The results support a novel role for Wnt signaling in cell cycle progression independent of β-catenin.


2019 ◽  
Vol 132 (2) ◽  
pp. jcs223123 ◽  
Author(s):  
Hidemasa Goto ◽  
Toyoaki Natsume ◽  
Masato T. Kanemaki ◽  
Aika Kaito ◽  
Shujie Wang ◽  
...  

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Ying Wu ◽  
Zhen Li ◽  
Sining Wang ◽  
Aiyuan Xiu ◽  
Chunqing Zhang

Aim. Carvedilol is a nonselective beta-blocker used to reduce portal hypertension. This study investigated the effects and potential mechanisms of carvedilol in angiotensin II- (Ang II-) induced hepatic stellate cell (HSC) proliferation and contraction. Methods. The effect of carvedilol on HSC proliferation was measured by Cell Counting Kit-8 (CCK-8). Cell cycle progression and apoptosis in HSCs were determined by flow cytometry. A collagen gel assay was used to confirm HSC contraction. The extent of liver fibrosis in mice was evaluated by hematoxylin-eosin (H&E) and Sirius Red staining. Western blot analyses were performed to detect the expression of collagen I, collagen III, α-smooth muscle actin (α-SMA), Ang II type I receptor (AT1R), RhoA, Rho-kinase 2 (ROCK2), and others. Results. The results showed that carvedilol inhibited HSC proliferation and arrested the cell cycle at the G0/G1 phase in a dose-dependent manner. Carvedilol also modulated Bcl-2 family proteins and increased apoptosis in Ang II-treated HSCs. Furthermore, carvedilol inhibited HSC contraction induced by Ang II, an effect that was associated with AT1R-mediated RhoA/ROCK2 pathway interference. In addition, carvedilol reduced α-SMA expression and collagen deposition and attenuated liver fibrosis in carbon tetrachloride (CCl4)-treated mice. The in vivo data further confirmed that carvedilol inhibited the expression of angiotensin-converting enzyme (ACE), AT1R, RhoA, and ROCK2. Conclusions. The results indicated that carvedilol dose-dependently inhibited Ang II-induced HSC proliferation by impeding cell cycle progression, thus alleviating hepatic fibrosis. Furthermore, carvedilol could inhibit Ang II-induced HSC contraction by interfering with the AT1R-mediated RhoA/ROCK2 pathway.


2009 ◽  
Vol 185 (2) ◽  
pp. 193-202 ◽  
Author(s):  
Arne Lindqvist ◽  
Verónica Rodríguez-Bravo ◽  
René H. Medema

The decision to enter mitosis is mediated by a network of proteins that regulate activation of the cyclin B–Cdk1 complex. Within this network, several positive feedback loops can amplify cyclin B–Cdk1 activation to ensure complete commitment to a mitotic state once the decision to enter mitosis has been made. However, evidence is accumulating that several components of the feedback loops are redundant for cyclin B–Cdk1 activation during normal cell division. Nonetheless, defined feedback loops become essential to promote mitotic entry when normal cell cycle progression is perturbed. Recent data has demonstrated that at least three Plk1-dependent feedback loops exist that enhance cyclin B–Cdk1 activation at different levels. In this review, we discuss the role of various feedback loops that regulate cyclin B–Cdk1 activation under different conditions, the timing of their activation, and the possible identity of the elusive trigger that controls mitotic entry in human cells.


2004 ◽  
Vol 149 (2-3) ◽  
pp. 125-136 ◽  
Author(s):  
Pei-Ming Yang ◽  
Shu-Jun Chiu ◽  
Kwei-Ann Lin ◽  
Lih-Yuan Lin

2020 ◽  
Vol 117 (35) ◽  
pp. 21609-21617
Author(s):  
Zhenxing Liu ◽  
Christopher P. Selby ◽  
Yanyan Yang ◽  
Laura A. Lindsey-Boltz ◽  
Xuemei Cao ◽  
...  

The circadian clock is a global regulatory mechanism that controls the expression of 50 to 80% of transcripts in mammals. Some of the genes controlled by the circadian clock are oncogenes or tumor suppressors. Among theseMychas been the focus of several studies which have investigated the effect of clock genes and proteins onMyctranscription and MYC protein stability. Other studies have focused on effects ofMycmutation or overproduction on the circadian clock in comparison to their effects on cell cycle progression and tumorigenesis. Here we have used mice with mutations in the essential clock genesBmal1,Cry1,andCry2to gain further insight into the effect of the circadian clock on this important oncogene/oncoprotein and tumorigenesis. We find that mutation of bothCry1andCry2, which abolishes the negative arm of the clock transcription–translation feedback loop (TTFL), causes down-regulation of c-MYC, and mutation ofBmal1,which abolishes the positive arm of TTFL, causes up-regulation of the c-MYC protein level in mouse spleen. These findings must be taken into account in models of the clock disruption–cancer connection.


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