Decreased Cell Differentiation Research Articles

Nanoplastics exposure-induced mitochondrial dysfunction contributes to disrupted stem cell differentiation in human cerebral organoids

Nanoplastics are ubiquitous in our daily lives, raising concerns about their potential impact on the human brain. Many studies reported that nanoplastics permeate the blood-brain barrier and influence cellular processes in mouse models. However, the neurotoxic effects of ingesting nanoplastics on human brain remain poorly understood. Here, we treated cerebral organoids with polystyrene nanoplastics to model the effects of nanoplastic exposure on human brain. Importantly, we found that mitochondria might be the significant organelles affected by polystyrene nanoplastics using immunostaing and RNA-seq analysis. Subsequently, we observed the increased cell death and decreased cell differentiation in our cerebral organoids. In conclusion, our findings shed insights on the mechanisms underlying the toxicity of nanoplastics on human brain organoids, providing an evaluation system in detection potential environmental toxicity on human brain.

Multi-directional Changes in 8-OHdG Concentration in Saliva during HER2 Expression in Breast Cancer

The purpose of this work was to evaluate changes in the structure of 8-OHdG in saliva in patients with breast cancer depending on molecular biological subtypes. The findings show that decreased salivary 8-OHdG concentrations in the HER2-positive group rapidly correlated with decreased cell differentiation and high Ki-67 levels, reflecting the aggressive nature of the tumor disease and poor survival prognosis. Thus, the presence of high levels of 8-OHdG in the oral cavity may lead to the development of the role of a biological marker of the HER2-positive group with a poor prognosis of breast cancer and can be used as an additional method of diagnosis, patient condition and response to therapy.

The ROS/SIRT1/STAR axis as a target for melatonin ameliorating atrazine-induced mitochondrial dysfunction and steroid disorders in granulosa cells

The granulosa cells (GCs) of birds are essential for the reproduction and maintenance of populations in nature. Atrazine (ATR) is a potent endocrine disruptor that can interfere with reproductive function in females and Diaminochlorotriazine (DACT) is the primary metabolite of ATR in the organism. Melatonin (MT) is an endogenous hormone with antioxidant properties that plays a crucial role in development of animal germ cells. However, how ATR causes mitochondrial dysfunction, abnormal secretion of steroid hormones, and whether MT prevents ATR-induced female reproductive toxicity remains unclear. Thus, the purpose of this study is to investigate the protective effect of MT against ATR-induced female reproduction. In the present study, the GCs of quail were divided into 6 groups, as follows: C (Serum-free medium), MT (10 µM MT), A250 (250 µM ATR), MA250 (10 µM MT+250 µM ATR), D200 (200 µM DACT) and MD200 (10 µM MT+200 µM DACT), and were cultured for 24 h. The results revealed that ATR prevented GCs proliferation and decreased cell differentiation. ATR caused oxidative damage and mitochondrial dysfunction, leading to disruption of steroid synthesis, which posed a severe risk to GC's function. However, MT supplements reversed these changes. Mechanistically, our study exhibited that the ROS/SIRT1/STAR axis as a target for MT to ameliorate ATR-induced mitochondrial dysfunction and steroid disorders in GCs, which provides new insights into the role of MT in ATR-induced reproductive capacity and species conservation in birds.

IPA and its precursors differently modulate the proliferation, differentiation, and integrity of intestinal epithelial cells.

Indole-3-propionic acid (IPA) is a tryptophan-derived microbial metabolite that has been associated with protective effects against inflammatory and metabolic diseases. However, there is a lack of knowledge regarding the effects of IPA under physiological conditions and at the intestinal level. Human intestinal epithelial Caco-2 cells were treated for 2, 24, and/or 72 h with IPA or its precursors - indole, tryptophan, and propionate - at 1, 10, 100, 250, or 500 μM to assess cell viability, integrity, differentiation, and proliferation. IPA induced cell proliferation and this effect was associated with a higher expression of extracellular signal-regulated kinase 2 (ERK2) and a lower expression of c-Jun. Although indole and propionate also induced cell proliferation, this involved ERK2 and c-Jun independent mechanisms. On the other hand, both tryptophan and propionate increased cell integrity and reduced the expression of claudin-1, whereas propionate decreased cell differentiation. In conclusion, these findings suggested that IPA and its precursors distinctly contribute to the proliferation, differentiation, and barrier function properties of human intestinal epithelial cells. Moreover, the pro-proliferative effect of IPA in intestinal epithelial cells was not explained by its precursors and is rather related to its whole chemical structure. Maintaining IPA at physiological levels, e.g., through IPA-producing commensal bacteria, may be important to preserve the integrity of the intestinal barrier and play an integral role in maintaining metabolic homeostasis.

109. Vitamin E Treated Fat Grafts Maintain Volume to Improve Grafting Effects on Radiation-induced Fibrosis

Introduction: Fat grafts and vitamin E administration have both previously been described to mitigate radiation-induced skin fibrosis. Fat graft retention continues to hinder its long-term functionality affected mainly by two factors: initial inflammatory response and chronic necrosis secondary to hypovascularity. Thus, we aimed to simultaneously improve fat graft retention along with radiation-induced fibrosis. Methods: Ten adult CD-1 nude male mice at 6-8 weeks of age underwent scalp irradiation with 5 Gy every other day for 12 days, totaling in 30 Gy. Mice recovered for four weeks to allow chronic fibrosis to develop. After recovery, mice received 1000μL of donor human fat graft to the scalp. Mice were separated into 4 conditions: ungrafted irradiated, untreated fat graft, fat graft treated with pentoxifylline (PTX), fat graft treated with vitamin E (VE). Fat graft volume retention was monitored in-vivo using microCT scans with 3-dimensional reconstruction and analysis at weeks 0, 1, 2, 4, 6, and 8 after grafting. Fat graft and overlying skin were harvested and underwent histological and cytokine analysis. Results: Histological analysis demonstrated improvement in radiation-induced fibrosis, CD31+ expression, and 8-isoprostane expression in the vitamin E group. Cytokine analysis revealed decreased cell differentiation markers and inflammatory markers. Fat graft volume retention significantly improved as early as 1 week post-grafting with local vitamin E administration compared to control. Conclusion: Radiation-induced fibrosis and fat graft volume retention are both simultaneously improved with novel, local administration of vitamin E, improving both cosmesis and functionality of fat grafting in chronically irradiated fields.

Methionine deficiency and its hydroxy analogue influence chicken intestinal 3-dimensional organoid development.

Methionine and its hydroxy analogue (MHA) have been shown to benefit mouse intestinal regeneration. The intestinal organoid is a good model that directly reflects the impact of certain nutrients or chemicals on intestinal development. Here, we aimed to establish a chicken intestinal organoid culture method first and then use the model to explore the influence of methionine deficiency and MHA on intestinal organoid development. The results showed that 125-μm cell strainer exhibited the highest efficiency for chicken embryo crypt harvesting. We found that transforming growth factor-β inhibitor (A8301) supplementation promoted enterocyte differentiation at the expense of the proliferation of intestinal stem cells (ISC). The mitogen-activated protein kinase p38 inhibitor (SB202190) promoted intestinal organoid formation and enterocyte differentiation but suppressed the differentiation of enteroendocrine cells, goblet cells and Paneth cells. However, the suppression of enteroendocrine cell and Paneth cell differentiation by SB202190 was alleviated at the presence of A8301. The glycogen synthase kinase 3 inhibitor (CHIR99021), valproic acid (VPA) alone and their combination promoted chicken intestinal organoid formation and enterocyte differentiation at the expense of the expression of Paneth cells and goblet cells. Chicken serum significantly improved organoid formation, especially in the presence of A8301, SB202190, CHIR99021, and VPA, but inhibited the differentiation of Paneth cells and enteroendocrine cells. Chicken serum at a concentration of 0.25% meets the requirement of chicken intestinal organoid development, and the beneficial effect of chicken serum on chicken intestinal organoid culture could not be replaced by fetal bovine serum and insulin-like growth factor-1. Moreover, commercial mouse organoid culture medium supplemented with A8301, SB202190, CHIR99021, VPA, and chicken serum promotes chicken organoid budding. Based on the chicken intestinal organoid model, we found that methionine deficiency mimicked by cycloleucine suppressed organoid formation and organoid size, and this effect was reinforced with increased cycloleucine concentrations. Methionine hydroxy analogue promoted regeneration of ISC but decreased cell differentiation compared with the results obtained with L-methionine. In conclusion, our results provide a potentially excellent guideline for chicken intestinal organoid culture and insights into methionine function in crypt development.

MiRNA-1202 promotes the TGF-β1-induced proliferation, differentiation and collagen production of cardiac fibroblasts by targeting nNOS.

BackgroundAtrial fibrillation (AF) is a clinically common arrhythmia that affects human health. Myocardial fibrosis serves as an important contributor to AF. Recently, miRNA-1202 have been reported to be up-regulated in AF. However, the role of miRNA-1202 and its mechanism in myocardial fibrosis remain unclear.MethodsHuman cardiac fibroblasts (HCFs) were used to construct a fibrosis model by TGF-β1 induction. The expression of miR-1202 was measured by qRT-PCR. Cell proliferation was assessed by CCK-8 assays. Protein expression levels were measured by western blot. Collagen accumulation was measured by ELISA. The relationship between miR-1202 and nNOS was investigated by luciferase reporter assays.ResultsMiR-1202 expression was obviously increased in HCFs and was both time- and dose-independent. MiR-1202 could increase the proliferation and collagen I, collagen III, and α-SMA levels with or without TGF-β1. MiR-1202 could also increase TGF-β1 and p-Smad2/3 protein levels in comparison to the control group. However, they were obviously decreased after inhibitor transfection. MiR-1202 targets nNOS for negative regulation of HCFs fibrosis by decreasing cell differentiation, collagen deposition and the activity of the TGF-β1/Smad2/3 pathway. Co-transfection of miR-1202 inhibitor and siRNA of nNOS inhibited nNOS protein expression, thereby enhancing the HCFs proliferation. Furthermore, co-transfection of the miR-1202 inhibitor and siRNA of nNOS significantly promoted collagen I, collagen III, TGF-β1, Smad2/3 and α-SMA protein expression and Smad2/3 protein phosphorylation. These findings suggested that miR-1202 promotes HCFs transformation to a pro-fibrotic phenotype by targeting nNOS through activating the TGF-β1/Smad2/3 pathway.

Effects of low-to-moderate ethanol consumption on colonic growth and gene expression in young adult and middle-aged male rats.

Excessive alcohol consumption is a risk factor associated with colorectal cancer; however, some epidemiological studies have reported that moderate alcohol consumption may not contribute additional risk or may provide a protective effect reducing colorectal cancer risk. Prior research highlights the importance of proliferation, differentiation, and apoptosis as parameters to consider when evaluating colonic cell growth and tumorigenesis. The present study investigated whether chronic low-to-moderate ethanol consumption altered these parameters of colonic cell growth and expression of related genes. Twenty-four nondeprived young adult (109 days old) and 24 nondeprived middle-aged (420 days old) Wistar rats were randomly assigned to an ethanol-exposed or a water control group (n = 12/group). The ethanol group was provided voluntary access to a 20% v/v ethanol solution on alternate days for 13 weeks. Colon tissues were collected for quantitative immunohistochemical analyses of cell proliferation, differentiation and apoptosis using Ki-67, goblet cell and TUNEL, respectively. Gene expression of cyclin D1 (Ccnd1), Cdk2, Cdk4, p21waf1/cip1 (Cdkn1a), E-cadherin (Cdh1) and p53 were determined by quantitative real-time polymerase chain reaction in colonic scraped mucosa. Ethanol treatment resulted in a lower cell proliferation index and proliferative zone, and lower Cdk2 expression in both age groups, as well as trends toward lower Ccnd1 and higher Cdkn1a expression. Cell differentiation was modestly but significantly reduced by ethanol treatment only in older animals. Overall, older rats showed decreases in apoptosis and gene expression of Cdk4, Cdh1, and p53 compared to younger rats, but there was no observed effect of ethanol exposure on these measures. These findings suggest that low-to-moderate ethanol consumption improves at least one notable parameter in colonic tumorigenesis (cell proliferation) and associated gene expression regardless of age, however, selectively decreased cell differentiation among older subjects.

High expression of the CKIP-1 gene might promote apoptosis through downregulation of the Ras/ERK signalling pathway in the intestinal type of gastric cancer.

ObjectiveTo investigate the effect of the casein kinase 2 interacting protein 1 (CKIP-1) on the apoptosis of the intestinal type of gastric cancer (GC).MethodsThe levels of CKIP-1 protein and the rates of apoptosis were measured in tissue samples of the intestinal type of GC and human GC cell lines. The rate of apoptosis and the protein levels of B cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein (Bax), cleaved cysteinyl aspartate specific protease 3 (cleaved caspase-3), cleaved caspase-9, rat sarcoma (Ras), extracellular signal-regulated kinase 1 and 2 (ERK1/2) and phosphorylated extracellular signal-regulated kinase 1 and 2 (p-ERK1/2) were analysed in SGC7901 cells expressing CKIP-1 short hairpin RNA (shRNA; knockdown) and SGC7901 cells overexpressing CKIP-1.ResultsThe levels of CKIP-1 protein were significantly lower in the intestinal type of GC tissues compared with the samples of intestinal metaplasia. Both the levels of CKIP-1 protein and the levels of apoptosis decreased gradually with decreasing cell differentiation in the intestinal type of GC tissue and cell lines; and they were positively correlated. In the CKIP-1 shRNA group, the rate of apoptosis and the levels of Bax, cleaved caspase-3 and cleaved caspase-9 were decreased; and the levels of Bcl-2, Ras and the ratio of p-ERK/ERK were increased, compared with the control group. Opposite results were observed in the CKIP-1 overexpression group.ConclusionHigh levels of CKIP-1 protein may promote apoptosis in the intestinal type of GC, possibly via the downregulation of the Ras/ERK signalling pathway.

Peroxisome proliferator-activated receptor-coactivator 1-beta (PGC-1β) modulates the expression of genes involved in adipogenesis during preadipocyte differentiation in chicken.

To study the influence of the PGC-1β gene on chicken adipocyte proliferation and differentiation, we constructed RNA interference (RNAi) vectors that target the PGC-1β gene and transfected these vectors into adipocytes. Oil Red O staining and a CCK-8 cell kit were used to determine cell triglyceride accumulation status and cell proliferation after transfection, respectively. The mRNA abundances of PGC-1β and adipocyte-differentiation-related genes (PPARγ, C/EBPα, SREBP-1c, FAS, and A-FABP) were detected by real-time PCR. The results showed that the mRNA and protein abundances of PGC-1β in PGC-1β-shRNA transfected adipocytes were significantly lower than those in the control. Interference decreased cell differentiation, but did not depress the cell proliferation. PGC-1β interference impeded the triglyceride accumulation, the mRNA expression levels of nuclear receptors PPARγ and SREBP-1c, and fatty acid synthetase (FAS), and both proteins PPARγ and SREBP-1c, and the fatty acids transporting protein A-FABP. Generally, PGC-1β modulated the cell differentiation and triglyceride accumulation in chicken adipocytes.

Interaction of Nel-like molecule 1 with apoptosis related protein 3 with its influence on human dental pulp cells proliferation and differentiation into odontoblasts

Nel-like molecule 1 (Nell-1) is an essential positive regulator of tooth development and odontoblast differentiation. However, its precise mechanism remains undetermined. This study aims to explore the possible receptor or binding protein of Nell-1. Results showed that Nell-1 and Apoptosis related protein 3(APR3) expression levels were high in odontoblasts and inversely correlated. Endogenous Nell-1 co-immunoprecipitated with APR3, and this co-IP was reciprocal. Double immunofluorescence staining revealed that Nell-1 and APR3 colocalized on the nuclear envelope of human dental pulp cells. Nell-1 inhibited the proliferation of these cells co-infected with APR3 through Cyclin D1 downregulation. The interaction of Nell-1 with APR3 stimulated alkaline phosphatase (ALP) activity and promoted the expression and mineralization of DSPP, ALP, OPN, and BSP. The shRNA of APR3 decreased cell differentiation and mineralization. Nell-1 could reciprocally interact with APR3 and stimulate the differentiation and mineralization of human dental pulp cells. Future studies should explore the potential functional connection and the molar mechanism of such interaction.

WDR13 promotes the differentiation of bovine skeletal muscle-derived satellite cells by affecting PI3K/AKT signaling.

Muscle satellite cells are usually at rest, and when externally stimulated or regulated, they can be further differentiated by cell fusion to form new myotubes and muscle fibers. WD repeat domain 13 (WDR13) is highly conserved in vertebrates. Studies have shown that mice lacking the Wdr13 gene develop mild obesity, hyperinsulinemia, and increased islet β cell proliferation. However, the role of WDR13 in bovine cells is unclear. Here, we investigated the effect of WDR13 on bovine skeletal muscle-derived satellite cells (MDSCs). We found that WDR13 was upregulated in bovine MDSCs using western blotting and immunofluorescence experiments. Moreover, activation and inhibition of WDR13 expression increased and decreased cell differentiation, respectively, suggesting that WDR13 promotes bovine MDSC differentiation. To further understand the mechanism of action of WDR13, we examined changes in the PI3K/AKT signaling pathway following WDR13 activation or inhibition. In addition, cells were treated with a phosphoinositide kinase 3 (PI3K) inhibitor, LY294004, to observe cell differentiation. The results showed that activation of WDR13 inhibited the PI3K/AKT signaling pathway and enhanced cell differentiation. These data suggest that WDR13 can promote the differentiation of bovine MDSCs by affecting the PI3K/AKT signaling pathway.

TRPM8 channel role in mesenchymal stem cells osteogenic differentiation

Mesenchymal stem cells (MSCs) have properties that make them a good model to use in regenerative medicine. MSCs proliferation and differentiation are complex processes involving the activation of several molecules that induces changes in intracellular calcium concentration. Different ion channels are responsible for calcium influx including TRP channels. The present study evaluates the expression and functional activity of TRPM8 channels in human mesenchymal stem cells. Cells were characterized by the expression of the specific surface markers CD90+, CD105+ and CD34− and by the ability to differentiate into adipogenic and osteogenic linage. Western blot, immunocytochemistry and flow cytometry were performed to determine TRPM8 protein expression. Patch clamp recordings and fluorescence imaging with Fluo‐4 AM were used to analyze channel activity. We found that the agonist menthol induces an increase in ionic currents which were incompletely abolished by treatment of the cells with the antagonist BCTC. Changes in intracellular calcium concentration were detected after addition of menthol, suggesting an effect induced by activation of TRPM8 channels. Alizarin red staining showed that the TRPM8 agonist Icilin increased osteogenic differentiation. On the contrary, the TRPM8 antagonist BCTC decreased cell differentiation. These results were confirmed by real time PCR with the marker Alkaline Phosphatase (ALP). Results from this study suggest that the activity of TRPM8 channels in mesenchymal stem cells is related with regulation of osteogenic differentiation.Support or Funding InformationThis work was supported by Departamento Administrativo de Ciencia, Tecnología e Innovación, COLCIENCIAS, Project: Evaluación del papel de canales TRPM8 en la diferenciación de células madre mesenquimales derivadas de tejido adiposo; Grant ID 120365843092.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effects of watermelon powder supplementation on colitis in high-fat diet-fed and dextran sodium sulfate-treated rats

Abstract The objective of this study was to determine the effects of watermelon on colitis in rats treated with Dextran Sodium Sulfate (DSS) and high-fat diet. We hypothesized that watermelon would reduce colitis severity by maintaining the number of intact crypts and regulating cell homeostasis. Forty rats were divided into four groups: control diet, control diet + DSS, 0.33% watermelon powder diet, and 0.33% watermelon powder diet + DSS. After 4 weeks of defined diets, DSS group rats were administered 3% (w/v) DSS (40 kDa) in their drinking water for 2 days. DSS administration increased colonocyte proliferation and apoptosis while decreasing cell differentiation and the number of intact colonic crypts (P

PRSS8 suppresses colorectal carcinogenesis and metastasis.

The serine protease PRSS8 has shown important physiological and pathological functions, but its roles in cancer initiation and progression are unclear. We developed and dynamically characterized a conditional knockout Prss8fl/fl, p-Villin-Cre+ mouse model. We found that genetic deficiency of the Prss8 gene caused spontaneous colitis and an inflamed rectum at an early age and caused intestinal tumors at a late age, which were linked to increased intestinal cell proliferation and migration but decreased cell differentiation. Increased PRSS8 expression inhibited cancer cell growth and metastasis in nude mice and inhibited cancer cell migration, invasion, colony formation and tumor sphere formation in vitro, but decreased PRSS8 expression facilitated malignancies in vivo and in vitro. Gene profiling on manipulated cancer cells and intestinal epithelial cells of Prss8 mouse models, gene set enrichment analysis and mechanistic studies revealed that PRSS8 targeted the Wnt/β-catenin, epithelial-mesenchymal transition, and stem cell signaling pathways, which were further supported by the results from the TCGA data mining and validated by immunohistochemical staining on colorectal cancer tissue microarrays. In conclusion, PRSS8 is a novel tumor suppressor that plays critical roles in the suppression of colorectal carcinogenesis and metastasis.

Abstract 4006: Serine protease PRSS8 suppresses colorectal carcinogenesis and metastasis

Abstract PRSS8 is a serine protease and has important physiological and pathophysiological functions, but its roles in cancer initiation and progression are unclear. In this study, a conditional knockout mouse model of Prss8 fl/fl,p-Villin-Cre+ mice were developed and thoroughly characterized at the ages of 3, 6 and 9 months. Intestinal epithelial cell proliferation, migration, and differentiation, were determined. The approaches of gain- and loss of expression of PRSS8 in human colon cancer cells were performed to evaluate anti-cancer and anti-metastasis in vitro and in nude mice by mouse subcutaneous injection, tail vein injection and intra-spleen transplantation. Gene profile and gene set enrichment analysis and mechanistic studies were conducted in vitro and in human colorectal cancer tissues. Results: Genetic deficiency of the Prss8 gene caused spontaneous formation of colitis and inflamed rectum at the early age, but caused intestinal tumors and lymph node metastasis at late age, which was linked to increased intestinal cell proliferation and migration, but decreased cell differentiation. Increased PRSS8 expression showed inhibition of cancer cell growth and metastasis in nude mice, and inhibited migration, invasion, colony formation and tumor sphere formation in vitro, but reduced expression of PRSS8 facilitated malignancies. Mechanistic studies revealed that PRSS8 targets Wnt/β-catenin, epithelial-mesenchymal-transition, and stem cell signaling pathways, which was supported by the results from the Cancer Genome Atlas, and were validated in human colorectal cancers. Conclusion: PRSS8 is a novel tumor suppressor that plays critical roles in the suppression of carcinogenesis and metastasis via targeting Wnt/β-catenin, EMT and stem cell signaling pathway. Citation Format: Yonghua Bao, Yongchen Guo, Yiqiong Yang, Xiaonan Wei, Xiangdong Zhu, Wei Zhang, Wancai Yang. Serine protease PRSS8 suppresses colorectal carcinogenesis and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4006.

Fascin1 promotes gastric cancer progression by facilitatingcell migrationand epithelial-mesenchymal transition

BackgroundFascin1 regulates cell motility, migration and invasion. Abnormal fascin1 expression has been implicated in a variety of cancers. In this study, we measured fascin1 expression in gastric cancer tissues from 80 gastric cancer patients, and assessed the correlation of fascin1 expression with a series of clinicopathologic gastric cancer parameters.We also verified the results with 4 gastric cancer cell lines in subsequent in vitro studies. MethodsWe measured mRNA expression of fascin1 with RT-qPCR, and measured protein expressions of fascin1 and EMT markers with western blot in gastric cancer cells. Additionally, we used RT-qPCR to assess fascin1 expression in gastric cancer tissues and adjacent normal tissue.Transwell assay was used for cell migration. Xenograft was established by subcutaneous injection of Fascin1 knockdown gastric cancer cells. ResultsFascin1 expression was greater in gastric cancer cell lines compared to normal cells and the expression increased with decreasing cell differentiation. In addition, fascin1 expression was significantly different between gastric cancer tissue and adjacent normal tissue. Fascin1 positivity was higher in poorly differentiated carcinomas compared to moderately and highly differentiated carcinomas. The fascin1 expression was associated with differentiation, tumor size, lymph node status, distant metastasis and TNM stage, but not patient age and sex. Fascin1 expression in gastric carcinoma cells and tissues is significantly higher than in normal gastric mucosa and adjacent tissue to cancerous tissues, and it increases as cancer cell differentiation decreases. Furthermore, fascin1 expression regulates gastric cancer cell migration, expressions of EMT markers and transcription factors as well as xenograft tumor formation. ConclusionFascin1 is related with clinicopathologic parameters of gastric cancer and overexpressed both in gastric cell lines and gastric tumor tissue. Knockdown of Fascin1 inhibited gastric cancer cell migration and EMT markers expression.

Lacking of palladin leads to multiple cellular events changes which contribute to NTD

BackgroundThe actin cytoskeleton-associated protein palladin plays an important role in cell motility, morphogenesis and adhesion. In mice, Palladin deficient embryos are lethal before embryonic day (E) 15.5, and exhibit severe cranial neural tube and body wall closure defects. However, the mechanism how palladin regulates the process of cranial neural tube closure (NTC) remains unknown.MethodsIn this paper, we use gene knockout mouse to elucidate the function of palladin in the regulation of NTC process.ResultsWe initially focuse on the expression pattern of palladin and found that in embryonic brain, palladin is predominantly expressed in the neural folds at E9.5. We further check the major cellular events in the neural epithelium that may contribute to NTC during the early embryogenesis. Palladin deficiency leads to a disturbance of cytoskeleton in the neural tube and the cultured neural progenitors. Furthermore, increased cell proliferation, decreased cell differentiation and diminished apical cell apoptosis of neural epithelium are found in palladin deficient embryos. Cell cycle of neural progenitors in Palladin-/- embryos is much shorter than that in wt ones. Cell adhesion shows a reduction in Palladin-/- neural tubes.ConclusionsPalladin is expressed with proper spatio-temporal pattern in the neural folds. It plays a crucial role in regulating mouse cranial NTC by modulating cytoskeleton, proliferation, differentiation, apoptosis, and adhesion of neural epithelium. Our findings facilitate further study of the function of palladin and the underlying molecular mechanism involved in NTC.

Osteocalcin Induces Proliferation via Positive Activation of the PI3K/Akt, P38 MAPK Pathways and Promotes Differentiation Through Activation of the GPRC6A-ERK1/2 Pathway in C2C12 Myoblast Cells

Background/Aims: Sarcopenia is characterized by an age-related decline in skeletal muscle plus low muscle strength and/or physical performance. Despite the clinical significance of sarcopenia, the molecular pathways underlying sarcopenia remain elusive. The recent demonstration that undercarboxylated osteocalcin (ucOC) favours muscle function related to insulin sensitivity and glucose metabolism raises the question of whether this hormone may also regulate muscle mass. The present study explored the promotive effects of ucOC in proliferation and differentiation processes of C2C12 myoblasts as well as the possible signalling pathways involved. Methods: The effects of exogenous ucOC on C2C12 myoblasts proliferation were assessed using CCK8 and immunohistological staining assays. C2C12 cells were pretreated with PI3K/Akt or P38 MAPK inhibitors to investigate the possible involvement of the PI3K/Akt and P38 MAPK pathways in proliferation. The levels of Akt, phosphorylated-Akt (p-Akt), P38, and phosphorylated-P38 (p-P38) were measured by Western Blotting. The effects of ucOC on myoblast differentiation were quantified by morphological analysis. A silencing experiment was conducted in which the expression of GPRC6A in C2C12 myoblasts was modified. The expression of GPRC6A, myosin heavy chain (MyHC) and the related ERK1/2 signalling pathway in C2C12 myoblasts were monitored by qRT-PCR and Western Blotting. Results: We showed that treatment with exogenous ucOC stimulated the priming of C2C12 myoblasts proliferation. Inhibition of Akt phosphorylation by wortmannin or inhibition of P38 MAPK phosphorylation by SB203580 decreased C2C12 cell proliferation. Wortmannin also reduced P38 MAPK phosphorylation, whereas SB203580 did not affect Akt activation. Furthermore, ucOC promoted C2C12 myoblast differentiation. Inhibition of ERK1/2 phosphorylation with U0126 decreased C2C12 cell differentiation. Finally, GPRC6A expression was substantially increased after ucOC treatment of C2C12 cells. GPRC6A silencing inhibited Akt, P38 MAPK phosphorylation in C2C12 cells, and ERK1/2 phosphorylation in C2C12 myotubes; GPRC6A silencing also decreased cell proliferation, decreased cell differentiation, and downregulated MyHC expression. Conclusions: The present data suggest that ucOC induces myoblast proliferation via sequential activation of the PI3K/Akt and p38 MAPK pathways in C2C12 myoblast cells. Moreover, ucOC enhances myogenic differentiation via a mechanism involving GPRC6A-ERK1/2 signalling.

Alcohol and cancer: an overview with special emphasis on the role of acetaldehyde and cytochrome P450 2E1.

The mechanisms by which chronic alcohol consumption enhances carcinogenesis include acetaldehyde (AA) generated by alcohol dehydrogenase and reactive oxygen species (ROS) generated predominantly by cytochrome P450 2E1 (CYP2E1), but also by other factors during inflammation. In addition, ethanol also alters epigenetics by changing DNA and histone methylation and acetylation. A loss of retinoic acid due to a CYP2E1-related enhanced degradation results in enhanced cellular proliferation and decreased cell differentiation. Changes in cancer genes and in signaling pathways (MAPK, RAS, Rb, TGFβ, p53, PTEN, ECM, osteopontin, Wnt) may also contribute to ethanol-mediated mechanisms in carcinogenesis. Finally, immunosuppression may facilitate tumor spread. In the present review major emphasis is led on AA and ROS. While AA binds to proteins and DNA generating carcinogenic DNA adducts and inhibiting DNA repair and DNA methylation, ROS results in lipid peroxidation with the generation of lipid peroxidation products such as 4-hydoxynonenal which binds to DNA-forming highly carcinogenic exocyclic DNA adducts. ROS production correlates significantly with CYP2E1 in the liver but also in the esophagus, and its generation can be significantly reduced by the specific CYP2E1 inhibitor clomethiazole. Finally, CMZ also inhibits alcohol-mediated nitrosamine-induced hepatocarcinogenesis.