Journal of cellular biochemistry最新文献

The most common and aggressive brain cancer, glioblastoma, is characterized by hypoxia and poor survival. The pro-tumour transcription factor, hypoxia-inducible factor (HIF), is regulated via HIF-hydroxylases that require ascorbate as cofactor. Decreased HIF-hydroxylase activity triggers the hypoxic pathway driving cancer progression. Tissue ascorbate accumulates via the sodium-dependent vitamin C transporter-2 (SVCT2). We hypothesize that glioblastoma cells rely on SVCT2 for ascorbate accumulation, and that knockout of this transporter would disrupt the regulation of the hypoxic pathway by ascorbate. Ascorbate uptake was measured in glioblastoma cell lines (U87MG, U251MG, T98G) by high-performance liquid chromatography. CRISPR/Cas9 was used to knockout SVCT2. Cells were treated with cobalt chloride, desferrioxamine or 5% oxygen, with/without ascorbate, and key hypoxic pathway proteins were measured using Western blot analysis. Ascorbate uptake was cell line dependent, ranging from 1.7 to 11.0 nmol/10⁶ cells. SVCT2-knockout cells accumulated 90%-95% less intracellular ascorbate than parental cells. The hypoxic pathway was induced by all three stimuli, and ascorbate reduced this induction. In the SVCT2-knockout cells, ascorbate had limited effect on the hypoxic pathway. This study verifies that intracellular ascorbate is required to suppress the hypoxic pathway. As patient survival is related to an activated hypoxic pathway, increasing intra-tumoral ascorbate may be of clinical interest.

Retraction: D. Yan, D. Chen, and H.-J. Im, "Fibroblast Growth Factor-2 Promotes Catabolism via FGFR1-Ras-Raf-MEK1/2-ERK1/2 Axis That Coordinates With the PKCδ Pathway in Human Articular Chondrocytes," Journal of Cellular Biochemistry 113, no. 9 (2012): 2856-2865, https://doi.org/10.1002/jcb.24160. The above article, published online on 5 April 2012 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Christian Behl; and Wiley Periodicals LLC. The retraction has occurred due to concerns related to the data presented in the article raised by the Office of Research Compliance at Rush University Medical Center following an investigation jointly conducted by Rush University and the Jesse Brown Veterans Affairs Medical Center (JBVAMC). Specifically, image elements of the experimental data in Figures 2, 4 A and 5 C were found to have been used by the same author(s) for publication elsewhere in a different scientific context. The corresponding author, Dr. Hee-Jeong Im Sampen, has been informed of the decision to retract but did not agree with it, as she is confident that any errors in the publication do not impact the reliability of the paper's findings. She also advised the editors that she stands ready to cooperate fully to make any necessary corrections. However, the article is retracted as the editors lost trust in the accuracy of the data and consider the conclusions invalid.

Retraction: T. Gong, X. Ning, Z. Deng, M. Liu, B. Zhou, X. Chen, S. Huang, Y. Xu, Z. Chen, and R. Luo, "Propofol-Induced miR-219-5p Inhibits Growth and Invasion of Hepatocellular Carcinoma Through Suppression of GPC3-Mediated Wnt/β-Catenin Signalling Activation," Journal of Cellular Biochemistry 120, no. 10 (2019): 16934-16945, https://doi.org/10.1002/jcb.28952. The above article, published online on 19 May 2019 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; the journal Editor-in-Chief, Christian Behl; and Wiley Periodicals LLC. The retraction has been agreed due to concerns raised by third parties on the data presented in the article. Specifically, multiple areas of overlap were detected within and across Figures 1D, 2E and 2F. The authors acknowledged that unintentional mistakes were made during figure compilation and collaborated on the investigation into the detected issues. Even though they provided the raw data underlying the study, verification of the material's accuracy proved challenging due to the time elapsed since publication. As full accuracy of the provided material could no longer be ascertained, the editors have decided to retract the article, as they consider the identified issues to undermine the reliability of the presented research. The authors agree with the decision of retraction acknowledging that the identified issues may impact the overall interpretation of the research findings.

Retraction: H. Zhang, C. Feng, M. Zhang, A. Zeng, L. Si, N. Yu, and M. Bai, "MiR-625-5p/PKM2 Negatively Regulates Melanoma Glycolysis State," Journal of Cellular Biochemistry 120, no. 3 (2019): 2964-2972, https://doi.org/10.1002/jcb.26917. The above article, published online on 30 November 2018 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the authors; the journal Editor-in-Chief, Christian Behl; and Wiley Periodicals LLC. The authors requested a retraction of this manuscript stating that different cell lines were wrongly labelled and that the conclusions of this manuscript needed to be re-evaluated. Further investigation by the publisher revealed that the article mentions use of the non-verifiable/unknown normal skin cells HFE. Additional flaws and inconsistencies between results presented and experimental methods described were identified. Furthermore, the experimental methods were found to lack sufficient details or have unavailable supporting data, making the experiments not comprehensible nor reproducible to readers. Accordingly, the editors consider the conclusions of this article to be invalid.

Retraction: M. Hashemzehi, R. Behnam-Rassouli, S. M. Hassanian, M. Moradi-Binabaj, R. Moradi-Marjaneh, F. Rahmani, H. Fiuji, M. Jamili, M. Mirahmadi, N. Boromand, M. Piran, M. Jafari, A. Sahebkar, A. Avan, and M. Khazaei, "Phytosomal-curcumin Antagonizes Cell Growth and Migration, Induced by Thrombin Through AMP-Kinase in Breast Cancer," Journal of Cellular Biochemistry 119, no. 7 (2018): 5996-6007, https://doi.org/10.1002/jcb.26796. The above article, published online on 30 March 2018 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Christian Behl; and Wiley Periodicals LLC. The retraction has been agreed due to concerns raised by third parties on the data presented in the article. Specifically, possible duplication of Western Blot bands was identified within Figure 5. The raw data provided by the authors upon request did not address the concerns, as clear evidence of image manipulation and fabrication was detected. Consequently, the article is being retracted, as the editors have lost confidence in the integrity of the presented data and deem the conclusions invalid.

Decreased regenerative capacity of central nervous system neurons is the main cause for failure of damaged neuron regeneration and functional recovery. Long noncoding RNAs (lncRNAs) are abundant in mammalian transcriptomes, and many time- and tissue-specific lncRNAs are thought to be closely related to specific biological functions. The promoting effect of Pim-1 gene on neural differentiation and regeneration has been documented, but the effect and mechanism of its neighbor gene Lnc-Pim1 in regulating the response of central neurons to injury remain unclear. RT-PCR in this study demonstrated that the expression of Lnc-Pim1 was upregulated in acrylamide (ACR)-induced neuronal injury. FISH and nucleus-cytoplasmic assay demonstrated that Lnc-Pim1 was mainly expressed in the neuron cytoplasm, with a small amount in the nucleus. Western blot analysis proved that Lnc-Pim1 overexpression induced by the lentivirus vector could promote neurite outgrowth in Neuro-2a cells by activating the Erk1/2 signal pathway, and improve neurite regeneration of injured neurons by upregulating GAP-43 and β-Ⅲ tubulin protein expression. However, silencing Lnc-Pim1 expression by interfering RNA could effectively downregulate the GAP-43 and β-Ⅲ tubulin protein expression, and inhibit neurite growth of neurons. In addition, CHIRP-MS was performed to identify several potential targets of Lnc-Pim1 involved in the regulation of neurite regeneration of injured neurons. In conclusion, our study demonstrated that Lnc-Pim1 is a potential lnc-RNA, playing an important role in regulating central nerve regeneration.

Synaptic proteins are essential for neuronal development, synaptic transmission, and synaptic plasticity. The postsynaptic density (PSD) is a membrane-associated structure at excitatory synapses, which is composed of a huge protein complex. To understand the interactions and functions of PSD proteins, researchers have employed a variety of imaging and biochemical approaches including sophisticated mass spectrometry. However, the field is lacking a systematic comparison of different experimental conditions and how they might influence the study of the PSD interactome isolated from various tissue preparations. To evaluate the efficiency of several common solubilization conditions, we isolated receptors, scaffolding proteins, and adhesion molecules from brain tissue or primary cultured neurons or human forebrain neurons differentiated from induced pluripotent stem cells (iPSCs). We observed some striking differences in solubility. We found that N-methyl-d-aspartate receptors (NMDARs) and PSD-95 are relatively insoluble in brain tissue, cultured neurons, and human forebrain neurons compared to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptors (AMPARs) or SAP102. In general, synaptic proteins were more soluble in primary neuronal cultures and human forebrain neurons compared to brain tissue. Interestingly, NMDARs are relatively insoluble in HEK293T cells suggesting that insolubility does not directly represent the synaptic fraction but rather it is related to a detergent-insoluble fraction such as lipid rafts. Surprisingly, truncation of the intracellular carboxyl-terminal tail (C-tail) of NMDAR subunits increased NMDAR solubility in HEK293T cells. Our findings show that detergent, pH, and temperature are important for protein preparations to study PSD protein complexes, and NMDAR solubility is regulated by its C-tail, thus providing a technical guide to study synaptic interactomes and subcellular localization of synaptic proteins.

Despite significant advances in the treatment of cutaneous melanoma (hereafter melanoma), the prognosis remains less favorable due to therapeutic resistance, which is presumably linked to epigenetic dysregulation. We hypothesized that the histone lysine demethylase KDM4B could play a pivotal role in controlling therapy-resistant melanoma. To validate our hypothesis, we retrieved RNA sequencing data from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) program and observed upregulation of KDM4B in both primary and metastatic melanoma, which was associated with poor survival. To explore its role, we used murine B16, human SK-MEL-5, and G-361 melanoma cells as in vitro models of melanoma. We found that KDM4B inhibition using NCGC00244536 increased global levels of H3K9me3 and downregulated the expressions of cell cycle progression-related genes Cdk1, Cdk4, Ccnb1, and Ccnd1. Moreover, genetic ablation of KDM4B or its chemical inhibition using NCGC00244536 reduced p53 production by upregulating MDM2, which enhances the proteolytic degradation of p53. Interestingly, despite the reduction of p53, these interventions augmented apoptosis and senescence-induced cell death by activating pathways downstream of p53, as evidenced by reduced levels of pro-survival Bcl-2 and Bcl-xL proteins and increased production of pro-apoptotic cleaved caspase-3, caspase-7, Bax, and the senescence inducer Cdkn1a. Compared to the FDA-approved anti-melanoma agent dacarbazine, NCGC00244536 exhibited more pronounced cytotoxic and antiproliferative effects in melanoma cells. Importantly, NCGC00244536 demonstrated minimal cytotoxicity to low Kdm4b-expressing mouse embryonic fibroblasts. In conclusion, our findings suggest that KDM4B inhibition can override the antitumor effect of p53, and potentially serve as a therapeutic strategy for melanoma.

Human transmembrane serine protease 2 (TMPRSS2) is an important member of the type 2 transmembrane serine protease (TTSP) family with significant therapeutic markings. The search for potent TMPRSS2 inhibitors against severe acute respiratory syndrome coronavirus 2 infection with favorable tissue specificity and off-site toxicity profiles remains limited. Therefore, probing the anti-TMPRSS2 potential of enhanced drug delivery systems, such as nanotechnology and prodrug systems, has become compelling. We report the first in silico study of TMPRSS2 against a prodrug, [isopropyl(S)-2-((S)-2-acetamido-3-(1H-indol-3-yl)-propanamido)-6-diazo-5-oxo-hexanoate] also known as DRP-104 synthesized from 6-Diazo-5-oxo-l-norleucine (DON). We performed comparative studies on DON and DRP-104 against a clinically potent TMPRSS2 inhibitor, nafamostat, and a standard serine protease inhibitor, 4-(2-Aminoethyl) benzenesulfonyl fluoride (AEBSF) against TMPRSS2 and found improved TMPRSS2 inhibition through synergistic binding of the S1/S1' subdomains. Both DON and DRP-104 had better thermodynamic profiles than AEBSF and nafamostat. DON was found to confer structural stability with strong positive correlated inter-residue motions, whereas DRP-104 was found to confer kinetic stability with restricted residue displacements and reduced loop flexibility. Interestingly, the Scavenger Receptor Cysteine-Rich (SRCR) domain of TMPRSS2 may be involved in its inhibition mechanics. Two previously unidentified loops, designated X (270-275) and Y (293-296) underwent minimal and major structural transitions, respectively. In addition, residues 273-277 consistently transitioned to a turn conformation in all ligated systems, whereas unique transitions were identified for other transitioning residue groups in each TMPRSS2-inhibitor complex. Intriguingly, while both DON and DRP-104 showed similar loop transition patterns, DRP-104 preserved loop structural integrity. As evident from our systematic comparative study using experimentally/clinically validated inhibitors, DRP-104 may serve as a potent and novel TMPRSS2 inhibitor and warrants further clinical investigation.