MiR-221 Regulates Suppressors of Cytokine Signaling 3-Janus Kinase 2/Signal Transducer and Activator of Transcription 3 (SOCS3-JAK2/STAT3) Pathway and Affects Thyroid Cancer Cell Proliferation and Apoptosis

Objective: Suppressors of cytokine signaling 3 (SOCS3) negatively regulates JAK-STAT signaling. Bioinformatics analysis showed a targeted relationship between miR-221 and SOCS3 mRNA 3′-UTR. This study investigated whether miR-221 regulates SOCS3 expression and affects thyroid cancer cells. Methods: Dual-luciferase reporter gene experiments verified the relationship between miR-221 and SOCS3. The tumor tissues and adjacent tissues of patients with thyroid cancer were collected to detect miR-221 and SOCS3 level. Thyroid cancer cell line KTC-1 cells were assigned into miR-NC group and miR-221 inhibitor group followed by analysis of SOCS3, p-JAK2, and p-STAT3 level by Real-time PCR, cell apoptosis and cell proliferation by flow cytometry and cell invasion by Transwell assay. Results: Compared with adjacent tissues, miR-221 level in tumor tissues was increased, and SCOS3 mRNA level was decreased. There was a targeted relationship between miR-221 and SOCS3 mRNA. MiR-221 level in KTC-1 and TPC-1 cells was increased, while SOCS3 mRNA level was decreased. MiR-221 inhibitor can significantly upregulate SOCS3 mRNA and protein in KTC-1 cells, reduce the expression of p-JAK2, p-STAT3 protein, increase cell apoptosis, and reduce cell proliferation and invasion. Conclusion: The increased miR-221 and decreased SOCS3 expression are related to thyroid cancer pathogenesis. MiR-221 can inhibit the expression of SOCS3, affect JAK-STAT signaling activity, and regulate the proliferation and apoptosis of thyroid cancer cells.

miRNA-126 Inhibits Osteogenic Differentiation of Rat Bone Marrow Mesenchymal Stem Cells (BMSCs)

This study was to determine whether microRNA (miRNA)-126 regulates osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). Rat BMSCs were extracted and stimulated for osteogenic differentiation. Functional experiments were conducted to assess miR-126’s impact on BMSCs differentiation. Western blot and RT-qPCR determined miR-126 expression. ALP activity detection and alizarin red staining detection were also performed. After osteogenic differentiation of BMSCs, miR-126 expression was gradually decreased over time. Overexpression of miR-26 decreased ALP activity, Notch signaling activity as well as declined Runx2 expression and calcium Salt nodules after treatment. Importantly, we found that Smad4 serves as a target of miR-126 while upregulation of the miRNA was accompanied with the decreased Smad4 protein expression without affecting the Smad4 mRNA level. In conclusion, miR-126 restrains osteogenic differentiation through inhibition of SMAD4 signaling, providing a novel insight into the mechanism.

The Effect of High CDC6 Levels on Predicting Poor Prognosis in Colorectal Cancer

<b><i>Introduction:</i></b> We investigated the function of cell division cycle 6 (CDC6) on the prognosis in colorectal carcinoma (CRC). <b><i>Methods:</i></b> CDC6 protein expression levels in 121 patients with colorectal cancer and adjacent normal mucosa were detected by immunohistochemistry. <b><i>Results:</i></b> Compared to adjacent normal tissues, CDC6 mRNA level was overexpressed in CRC tissues. Moreover, CDC6 protein levels were expressed up to 93.39% (113/121) in CRC tissues in the cell nucleus or cytoplasm. However, there were only 5.79% (7/121) in normal mucosal tissues with nuclear expression. CDC6 expression was significantly correlated with TNM stage and tumor metastasis. The 5-year survival rate was lower in the high CDC6 expression group than the low group. After silencing of CDC6 expression in SW620 cells, cell proliferation was slowed, the tumor clones were decreased, and the cell cycle was arrested in G1 phase. In multivariate analysis, increased CDC6 protein expression levels in colon cancer tissues were associated with cancer metastasis, TNM stage, and patient survival time. <b><i>Conclusion:</i></b> CDC6 is highly expressed in CRC, and downregulation of CDC6 can slow the growth of CRC cells in vitro. It is also an independent predictor for poor prognosis and may be a useful biomarker for targeted therapy and prognostic evaluation.

Alcohol Promotes Exosome Biogenesis and Release via Modulating Rabs and miR-192 Expression in Human Hepatocytes

Exosomes are membrane vesicles released by various cell types into the extracellular space under different conditions including alcohol exposure. Exosomes are involved in intercellular communication and as mediators of various diseases. Alcohol use causes oxidative stress that promotes exosome secretion. Here, we elucidated the effects of alcohol on exosome biogenesis and secretion using human hepatocytes. We found that alcohol treatment induces the expression of genes involved in various steps of exosome formation. Expression of Rab proteins such as Rab1a, Rab5c, Rab6, Rab10, Rab11, Rab27a and Rab35 were increased at the mRNA level in primary human hepatocytes after alcohol treatment. Rab5, Rab6 and Rab11 showed significant induction in the livers of patients with alcohol-associated liver disease. Further, alcohol treatment also led to the induction of syntenin, vesicle-associated membrane proteins (VAMPs), and syntaxin that all play various roles in exosome biogenesis and secretion. VAMP3, VAMP5, VAPb, and syntaxin16 mRNA transcripts were increased in alcohol treated cells and in the livers of alcohol-associated liver disease (ALD) patients. Induction in these genes was associated with increases in exosome secretion in alcohol treated hepatocytes. We found that hepatocyte enriched miR-192 and miR-122 levels were significantly decreased in alcohol treated hepatocytes whereas their levels were increased in the cell-free supernatant. The primary transcripts of miR-192 and miR-122 were reduced in alcohol treated hepatocytes, suggesting alcohol partially affects these miRNAs at the transcriptional level. We found that miR-192 has putative binding sites for genes involved in exosome secretion. Inhibition of miR-192 in human hepatoma cells caused a significant increase in Rab27a, Rab35, syntaxin7 and syntaxin16 and a concurrent increase in exosome secretion, suggesting miR-192 regulates exosomes release in hepatocytes. Collectively, our results reveal that alcohol modulates Rabs, VAMPs and syntaxins directly and partly via miR-192 to induce exosome machinery and release.

Time-Course of Alterations in the Endocannabinoid System after Viral-Mediated Overexpression of α-Synuclein in the Rat Brain

Since the discovery of α-synuclein as the major component in Lewy bodies, research into this protein in the context of Parkinson’s disease pathology has been exponential. Cannabinoids are being investigated as potential therapies for Parkinson’s disease from numerous aspects, but still little is known about the links between the cannabinoid system and the pathogenic α-synuclein protein; understanding these links will be necessary if cannabinoid therapies are to reach the clinic in the future. Therefore, the aim of this study was to investigate the time-course of alterations in components of the endocannabinoid system after viral-mediated α-synuclein overexpression in the rat brain. Rats were given unilateral intranigral injections of AAV-GFP or AAV-α-synuclein and sacrificed 4, 8 and 12 weeks later for qRT-PCR and liquid chromatography–mass spectrometry analyses of the endocannabinoid system, in addition to histological visualization of α-synuclein expression along the nigrostriatal pathway. As anticipated, intranigral delivery of AAV-α-synuclein induced widespread overexpression of human α-synuclein in the nigrostriatal pathway, both at the mRNA level and the protein level. However, despite this profound α-synuclein overexpression, we detected no differences in CB1 or CB2 receptor expression in the nigrostriatal pathway; however, interestingly, there was a reduction in the expression of neuroinflammatory markers. Furthermore, there was a reduction in the levels of the endocannabinoid 2-AG and the related lipid immune mediator OEA at week 12 post-surgery, indicating that α-synuclein overexpression triggers dysregulation of the endocannabinoid system. Although this research does show that the endocannabinoid system is impacted by α-synuclein, further research is necessary to more comprehensively understand the link between the cannabinoid system and the α-synuclein aspect of Parkinson’s disease pathology in order for cannabinoid-based therapies to be feasible for the treatment of this disease in the coming years.

Naringenin Regulates FKBP4/NR3C1/NRF2 Axis in Autophagy and Proliferation of Breast Cancer and Differentiation and Maturation of Dendritic Cell

NRF2 is an important regulatory transcription factor involved in tumor immunity and tumorigenesis. In this study, we firstly identified that FKBP4/NR3C1 axis was a novel negative regulator of NRF2 in human breast cancer (BC) cells. The effect of FKBP4 appeared to be at protein level of NRF2 since it could not suppress the expression of NRF2 at mRNA level. Bioinformatics analysis and in vitro experiments further demonstrated that FKBP4 regulated NRF2 via regulating nuclear translocation of NR3C1. We then reported that naringenin, a flavonoid, widely distributed in citrus and tomato, could suppress autophagy and proliferation of BC cells through FKBP4/NR3C1/NRF2 signaling pathway in vitro and in vivo. Naringenin was also found to promote dendritic cell (DC) differentiation and maturation through FKBP4/NR3C1/NRF2 axis. Therefore, our study found that naringenin could induce inhibition of autophagy and cell proliferation in BC cells and enhance DC differentiation and maturation, at least in part, though regulation of FKBP4/NR3C1/NRF2 signaling pathway. Identification of FKBP4/NR3C1/NRF2 axis would provide insights for novel anti-tumor strategy against BC among tumor microenvironment.

CCND3 is indispensable for the maintenance of B-cell acute lymphoblastic leukemia

The D-type cyclins (CCND1, CCND2, and CCND3) in association with CDK4/6 are known drivers of cell cycle progression. We reported previously that inactivation of FOXO1 confers growth arrest and apoptosis in B-ALL, partially mediated by subsequent depletion of CCND3. Given that previously the canonical MYC target CCND2 has been considered to play the major role in B-ALL proliferation, further investigation of the role of FOXO1 in CCND3 transcription and the role of CCND3 in B-ALL is warranted. In this study, we demonstrated that CCND3 is essential for the proliferation and survival of B-ALL, independent of the mutational background. Respectively, its expression at mRNA level exceeds that of CCND1 and CCND2. Furthermore, we identified FOXO1 as a CCND3-activating transcription factor in B-ALL. By comparing the effects of CCND3 depletion and CDK4/6 inhibition by palbociclib on B-ALL cells harboring different driver mutations, we found that the anti-apoptotic effect of CCND3 is independent of the kinase activity of the CCND3-CDK4/6 complex. Moreover, we found that CCND3 contributes to CDK8 transcription, which in part might explain the anti-apoptotic effect of CCND3. Finally, we found that increased CCND3 expression is associated with the development of resistance to palbociclib. We conclude that CCND3 plays an essential role in the maintenance of B-ALL, regardless of the underlying driver mutation. Moreover, downregulation of CCND3 expression might be superior to inhibition of CDK4/6 kinase activity in terms of B-ALL treatment.

Interleukin 21 Receptor Affects Adipogenesis of Human Adipose-Derived Stem/Stromal Cells

Dysfunctions in adipose tissue cells are responsible for several obesity-related metabolic diseases. Understanding the process of adipocyte formation is thus fundamental for understanding these diseases. The adipocyte differentiation of adipose-derived stem/stromal cells (ADSCs) showed a reduction in the mRNA level of the interleukin 21 receptor (IL21R) during this process. Although the receptor has been associated with metabolic diseases, few studies have examined its function in stem cells. In this study, we used confocal immunofluorescence assays to determine that IL21R colocalizes with mitochondrial protein ATP5B, ALDH4A1, and the nucleus of human ADSCs. We demonstrated that silencing and overexpression of IL21R did not affect the cell proliferation and mitochondrial activity of ADSCs. However, IL21R silencing did reduce ADSC adipogenic capacity. Further studies are needed to understand the mechanism involved between IL21R and the adipogenic differentiation process.

CRISPR/Cas9 genome editing system confirms centriolin’s role in cytokinesis

Objective In addition to its function as the microtubule organizing center of the cell, the centrosome has functions in many other cellular processes including primary cilia formation, DNA damage checkpoints, and cell cycle progression. But the role of individual components of the centrosome in these processes remains unclear. Previous studies used siRNA (small interfering RNA) to “knock down” protein levels of the centrosome component centriolin, resulting in failed cytokinesis. Since this approach was transient, only targeting centriolin at the mRNA level, we sought to confirm these findings by permanently disrupting the gene encoding centriolin using the CRISPR/Cas9 system of genome editing. Results This study provides evidence that the CRISPR/Cas9 system is capable of effectively reducing centriolin protein levels in the cell. Furthermore, this disruption leads to a failure of cytokinesis that is reminiscent of the phenotype previously reported for the siRNA-mediated disruption of centriolin. Furthermore, no additional defects in cell division were observed, consistent with results seen with previous siRNA studies. We conclude that the CRISPR/Cas9 system is an effective means of permanently removing the cellular pools of centriolin and that the disruption of centriolin at both the mRNA level and genomic level lead to similar cell division defects.

Melatonin Induces Cell Cycle Arrest, Inhibits Cell Proliferation and Accelerates Apoptosis by Modulation of CDK4 in NSCLC

Purpose To explore whether melatonin affect the progression of cell cycle and exert anticancer activities via the modulation of CDK4 in NSCLC . Methods Cells treated with melatonin were used for assessing the anticancer effect of melatonin. Cells transfected with lentivirus for CDK4 upregulation or downregulation was constructed to evaluate the role of CDK4 in melatonin-induced anticancer effect. The protein and mRNA level of CDK4, PCNA and Bax were detected by western blotting and qRT-PCR. The application of flow cytometry was used for analyzing the distribution of cell cycle and apoptosis. Animal model of subcutaneous tumor was constructed and used for further study in vivo. Results We found that melatonin inhibited cell viability, colony formation, downregulated the expression of CDK4 and PCNA while upregulated the level of Bax. Besides, melatonin decreased the phosphorylation of ERK. Importantly, inhibition of ERK activation by PD98059 particapated in melatonin-induced downregulation of CDK4. Furthermore, melatonin led to G1 arrest and cell apoptosis. CDK4 knockdown enhanced melatonin-induced cell cycle arrest while CDK4 overexpression reversed the effect. Additionally, the animal experiment showed that melatonin decreased the level of CDK4 and inhibited tumor growth. However, the anti-tumor effect of melatonin was reversed by CDK4 overexpression. Conclusion Taken together, CDK4 involved in anti-cancer activities of melatonin. Melatonin led to G1 arrest, blocked G1-to-S transition, as a result, inhibited cell proliferation and accelerates apoptosis via suppressing CDK4 signaling. Targeting CDK4 inhibition and combining it with melatonin has protential to be a novel strategy for NSCLC.