RING finger and WD repeat domain 3 regulates proliferation and metastasis through the Wnt/β-catenin signalling pathways in hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC)exhibits high invasiveness and mortality rates,and the molecular mechanisms of HCC have gained increasing research interest.The abnormal DNA damage response has long been recognized as one of the important factors for tumor occurrence and development.Recent studies have shown the potential of the protein RING finger and WD repeat domain 3(RFWD3)that positively regulates p53 stability in response to DNA damage as a therapeutic target in cancers.AIM To investigate the relationship between HCC and RFWD3 in vitro and in vivo and explored the underlying molecular signalling transduction pathways.METHODS RFWD3 gene expression was analyzed in HCC tissues and adjacent normal tissues.Lentivirus was used to stably knockdown RFWD3 expression in HCC cell lines.After verifying the silencing efficiency,Celigo/cell cycle/apoptosis and MTT assays were used to evaluate cell proliferation and apoptosis.Subsequently,cell migration and invasion were assessed by wound healing and transwell assays.In addition,transduced cells were implanted subcutaneously and injected into the tail vein of nude mice to observe tumor growth and metastasis.Next,we used lentiviral-mediated rescue of RFWD3 shRNA to verify the phenotype.Finally,the microarray,ingenuity pathway analysis,and western blot analysis were used to analyze the regulatory network underlying HCC.RESULTS Compared with adjacent tissues,RFWD3 expression levels were significantly higher in clinical HCC tissues and correlated with tumor size and TNM stage(P<0.05),which indicated a poor prognosis state.RFWD3 silencing in BEL-7404 and HCC-LM3 cells increased apoptosis,decreased growth,and inhibited the migration in shRNAi cells compared with those in shCtrl cells(P<0.05).Furthermore,the in vitro results were supported by the findings of the in vivo experiments with the reduction of tumor cell invasion and migration.Moreover,the rescue of RFWD3 shRNAi resulted in the resumption of invasion and metastasis in HCC cell lines.Finally,gene expression profiling and subsequent experimental verification revealed that RFWD3 might influence the proliferation and metastasis of HCC via the Wnt/β-catenin signalling pathway.CONCLUSION We provide evidence for the expression and function of RFWD3 in HCC.RFWD3 affects the prognosis,proliferation,invasion,and metastasis of HCC by regulating the Wnt/β-catenin signalling pathway.

Novel insights into mTOR signalling pathways: A paradigm for targeted tumor therapy

As a crucial protein kinase,the mammalian target of rapamycin(mTOR)intimately controls essential cellular processes like cell development,proliferation,metabolism,and other crucial activities.Different cancers and disorders have been linked to imbalances in mTOR's regulatory systems.Multiple mTOR inhibitor therapy has recently acquired popularity as a method of treating cancers brought on by abnormal signal transduction pathways.We also explore potential processes behind tumor cell resistance to mTOR inhibitors and suggest workarounds to overcome this challenge.We hold the potential to pioneer cutting-edge methods for tumor therapy by methodically examining the complex mTOR signaling system and its regulatory complexity.Increasing our knowledge of mTOR-related mechanisms not only creates opportunities for cutting-edge methods to target and treat cancers but also has the potential to improve patient outcomes and general quality of life significantly.This review paper explores the most recent developments in understanding mTOR signaling pathways and the use of mTOR inhibitors in treating tumors.

Sustained adenosine release:Revealing its impact on osteogenic signalling pathways of human mesenchymal stromal cells

Non-healing fractures,a global health concern arising from trauma,osteoporosis,and tumours,can lead to severe disabilities.Adenosine,integral to cellular energy metabolism,gains prominence in bone regeneration via adeno-sine A2 B receptor activation.This study introduces a controlled-release system for localized adenosine delivery,fostering human mesenchymal stromal cell(hMSC)differentiation into functional bone cells.The study investi-gates how the ratio of lactic acid to glycolic acid in microparticles can influence adenosine release and explores the downstream effects on gene expression and metabolic profiles of osteogenic differentiation in hMSCs cultured in growth and osteoinductive media.Insights into adenosine-modulated signalling pathways during MSC differenti-ation,with osteogenic factors,provide a comprehensive understanding of the pathways involved.Analysing gene expression and metabolic profiles unravels adenosine’s regulatory mechanisms in MSC differentiation.Sustained adenosine release from microparticles induces mineralization,synergizing with osteogenic media supplements,showcasing the potential of adenosine for treating critical bone defects and metabolic disorders.This study high-lights the efficacy of a polymeric microparticle-based delivery system,offering novel strategies for bone repair.Unveiling adenosine’s roles and associated signalling pathways advances our comprehension of molecular mech-anisms steering bone regeneration,propelling innovative biomaterial,combined with metabolites,approaches for clinical use.

Traditional Chinese medicine in the treatment of Helicobacter pylorirelated gastritis:The mechanisms of signalling pathway regulations

Helicobacter pylori-associated gastritis(HPAG)is a common condition of the gastrointestinal tract.However,extensive and long-term antibiotic use has resulted in numerous adverse effects,including increased resistance,gastrointestinal dysfunction,and increased recurrence rates.When these concerns develop,traditional Chinese medicine(TCM)may have advantages.TCM is based on the concept of completeness and aims to eliminate pathogens and strengthen the body.It has the potential to prevent this condition while also boosting the rate of Helicobacter pylori eradication.This review elaborates on the mechanism of TCM treatment for HPAG based on cellular signalling pathways,which reflects the flexibility of TCM in treating diseases and the advantages of multi-level,multipathway,and multi-target treatments for HPAG.

Molecular mechanism of pancreatic ductal adenocarcinoma:The heterogeneity of cancer-associated fibroblasts and key signaling pathways

Pancreatic ductal adenocarcinoma stands out as an exceptionally fatal cancer owing to the complexities associated with its treatment and diagnosis,leading to a notably low five-year survival rate.This study offers a detailed exploration of epidemiological trends in pancreatic cancer and key molecular drivers,such as mutations in CDKN2A,KRAS,SMAD4,and TP53,along with the influence of cancer-associated fibroblasts(CAFs)on disease progression.In particular,we focused on the pivotal roles of signaling pathways such as the transforming growth factor-βand Wnt/β-catenin pathways in the development of pancreatic cancer and investigated their application in emerging therapeutic strategies.This study provides new scientific perspectives on pancreatic cancer treatment,especially in the development of precision medicine and targeted therapeutic strategies,and demonstrates the importance of signaling pathway research in the development of effective therapeutic regimens.Future studies should explore the subtypes of CAFs and their specific roles in the tumor microenvironment to devise more effective therapeutic methods.

Melatonin influences the biological characteristics of keloid fibroblasts through the Erk and Smad signalling pathways

Background:Keloids are abnormal fibrous hyperplasias that are difficult to treat.Melatonin can be used to inhibit the development of certain fibrotic diseases but has never been used to treat keloids.We aimed to discover the effects and mechanisms of melatonin in keloid fibroblasts(KFs).Methods:Flow cytometry,CCK-8 assays,western blotting,wound-healing assays,transwell assays,collagen gel contraction assays and immunofluorescence assays were applied to demonstrate the effects and mechanisms of melatonin in fibroblasts derived from normal skin,hypertrophic scars and keloids.The therapeutic potential of the combination of melatonin and 5-fluorouracil(5-FU)was investigated in KFs.Results:Melatonin significantly promoted cell apoptosis and inhibited cell proliferation,migration and invasion,contractile capability and collagen production in KFs.Further mechanistic studies demonstrated that melatonin could inhibit the cAMP/PKA/Erk and Smad pathways through the membrane receptor MT2 to alter the biological characteristics of KFs.Moreover,the combination of melatonin and 5-FU remarkably promoted cell apoptosis and inhibited cell migration and invasion,contractile capability and collagen production in KFs.Furthermore,5-FU suppressed the phosphorylation of Akt,mTOR,Smad3 and Erk,and melatonin in combination with 5-FU markedly suppressed the activation of the Akt,Erk and Smad pathways.Conclusions:Collectively,melatonin may inhibit the Erk and Smad pathways through the mem-brane receptor MT2 to alter the cell functions of KFs,while combination with 5-FU could exert even more inhibitory effects in KFs through simultaneous suppression of multiple signalling pathways.

Extracellular vesicles modulate key signalling pathways in refractory wound healing

Chronic wounds are wounds that cannot heal properly due to various factors,such as underlying diseases,infection or reinjury,and improper healing of skin wounds and ulcers can cause a serious economic burden.Numerous studies have shown that extracellular vesicles(EVs)derived from stem/progenitor cells promote wound healing,reduce scar formation and have significant advantages over traditional treatment methods.EVs are membranous particles that carry various bioactive molecules from their cellular origins,such as cytokines,nucleic acids,enzymes,lipids and proteins.EVs can mediate cell-to-cell communication and modulate various physiological processes,such as cell differentiation,angiogenesis,immune response and tissue remodelling.In this review,we summarize the recent advances in EV-based wound healing,focusing on the signalling pathways that are regulated by EVs and their cargos.We discuss how EVs derived from different types of stem/progenitor cells can promote wound healing and reduce scar formation by modulating the Wnt/β-catenin,phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin,vascular endothelial growth factor,transforming growth factorβand JAK-STAT pathways.Moreover,we also highlight the challenges and opportunities for engineering or modifying EVs to enhance their efficacy and specificity for wound healing.

Cinobufotalin prevents bone loss induced by ovariectomy in mice through the BMPs/SMAD and Wnt/β-catenin signaling pathways

Background:Osteoporosis is a chronic bone disease characterized by bone loss and decreased bone strength.However,current anti-resorptive drugs carry a risk of various complications.The deep learning-based efficacy prediction system(DLEPS)is a forecasting tool that can effectively compete in drug screening and prediction based on gene expression changes.This study aimed to explore the protective effect and potential mechanisms of cinobufotalin(CB),a traditional Chinese medicine(TCM),on bone loss.Methods:DLEPS was employed for screening anti-osteoporotic agents according to gene profile changes in primary osteoporosis.Micro-CT,histological and morphological analysis were applied for the bone protective detection of CB,and the osteogenic differentiation/function in human bone marrow mesenchymal stem cells(hBMMSCs)were also investigated.The underlying mechanism was verified using qRT-PCR,Western blot(WB),immunofluorescence(IF),etc.Results:A safe concentration(0.25mg/kg in vivo,0.05μM in vitro)of CB could effectively preserve bone mass in estrogen deficiency-induced bone loss and promote osteogenic differentiation/function of hBMMSCs.Both BMPs/SMAD and Wnt/β-catenin signaling pathways participated in CB-induced osteogenic differentiation,further regulating the expression of osteogenesis-associated factors,and ultimately promoting osteogenesis.Conclusion:Our study demonstrated that CB could significantly reverse estrogen deficiency-induced bone loss,further promoting osteogenic differentiation/function of hBMMSCs,with BMPs/SMAD and Wnt/β-catenin signaling pathways involved.

Reduction of the oxidative damage to H_(2)O_(2)-induced HepG2 cells via the Nrf2 signalling pathway by plant flavonoids Quercetin and Hyperoside

Hyperoside and quercetin are similar in molecular structures.In this study,the antioxidant regulatory targets of hyperoside and quercetin are mainly in the nuclear factor(erythroid-2-derived)-related factor 2(Nrf2)pathway predicted by network pharmacology.And the antioxidant effect and mechanism of hyperoside and quercetin were measured and compared in H_(2)O_(2)-induced Hep G2 cells and Caenorhabditis elegans.The findings indicated that quercetin was more effective than hyperoside in reducing oxidative damage,which was proved by improved cell viability,decreased reactive oxygen species(ROS)production,decreased cellular apoptosis,and alleviated mitochondrial damage.In addition,quercetin was more efficient than hyperoside in enhancing the expression of Nrf2-associated m RNAs,increasing the activities of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),and catalase(CAT),and reducing the cellular malondialdehyde(MDA)content.Quercetin was superior to hyperoside in prolonging the lifespan of worms,decreasing the accumulation of lipofuscin,inhibiting ROS production,and increasing the proportion of skn-1 in the nucleus.With the Nrf2 inhibitor ML385,we verified that quercetin and hyperoside primarily protected the cells against oxidative damage via the Nrf2 signalling pathway.Furthermore,molecular docking and dynamics simulations demonstrated that the quercetin-Kelch-like ECH-associated protein 1(Keap1)complex was more stable than the hyperoside-Keap1 complex.The stable structure of the complex might hinder the binding of Nrf2 and Keap1 to release Nrf2 and facilitate its entry into the nucleus to play an antioxidant role.Overall,quercetin had a better antioxidant than hyperoside.

TCGA-based analysis of oncogenic signaling pathways underlying oral squamous cell carcinoma

Background:Oral squamous cell carcinoma(OSCC)represents a prevalent malignancy in the oral and maxillofacial area,having a considerable negative impact on both the quality of life and overall survival of affected individuals.Our research endeavors to leverage bioinformatic approaches to elucidate oncogenic signaling pathways,with the ultimate goal of gaining deeper insights into the molecular underpinnings of OSCC pathogenesis,and thus laying the groundwork for the development of more effective therapeutic and preventive strategies.Methods:Differential expression analysis was performed on mRNA data from tumor and normal tissue groups to identify genes associated with OSCC,using The Cancer Genome Atlas database.Predictions of oncogenic signaling pathways linked to differentially expressedmRNAs were made,and these results were presented visually using R software,using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichments.Results:GO and KEGG analyses of 2938 differentially expressed genes in OSCC highlighted their significant involvement in various biological processes.Notably,these processes were related to the extracellular matrix,structural organization,connective tissue development,and cell cycle regulation.Conclusions:The comprehensive exploration of gene expression patterns provides valuable insights into potential oncogenic mechanisms in OSCC.

Pinacidil reduces neuronal apoptosis following cerebral ischemia-reperfusion in rats through both mitochondrial and death-receptor signal pathways

Objective To investigate effect of pinacidil, an ATP sensitive potassium channel （KATP） opener, on the neuronal apoptosis and its signaling transduction mechanism following focal cerebral ischemia-reperfusion in rats. Methods One hundred male Wistar rats were randomly divided into four groups： A, sham-operated group; B, ischemia-reperfusion group; C, KATe opener treatment group; and D, KATe opener and blocker treatment group. The middle cerebral artery occlusion （MCAO） model was established by using the intraluminal suture occlusion method, neuronal apoptosis was determined by TUNEL staining, and expressions of caspase-8, caspase-9 and caspase-3 mRNA were detected by in situ hybridization. Results （1） The numbers of apoptotic neurons at 12 h, 24 h, 48 h, and 72 h were significantly less in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there was no difference between groups B and D at all time points （P 〉 0.05）. （2） The expressions of caspase-3 mRNA and caspase-8 mRNA at all times and the expressions of caspase-9 mRNA at 12 h, 24 h, 48 h, 72 h were significantly lower in group C than in groups B and D （P 〈 0.01 or P 〈 0.05）; and there were no differences between groups B and D at all time points （P 〉 0.05）. Conclusions KATP opener can significantly decrease the neuronal apoptosis and the expressions of caspase-3, caspase-8 and caspase-9 mRNAs following cerebral ischemiareperfusion. The neuronal apoptosis may be decreased by the inhibition of both mitochondrial and death-receptor signal pathways.

The dopaminergic system and Alzheimer's disease

Alzheimer's disease is a common neurodegenerative disorder in older adults.Despite its prevalence,its pathogenesis remains unclea r.In addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this condition.Dopamine is a crucial catecholaminergic neurotransmitter in the human body.Dopamine-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical manifestations.Howeve r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive impairment.This review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related drugs.The aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases

The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain axis.The gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine systems.Conversely,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host interactions.This reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological diseases.The coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological diseases.This study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological diseases.Recent pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional disorders.This can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage forms.These findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases.

Engineered Cancer Nanovaccines:A New Frontier in Cancer Therapy

Vaccinations are essential for preventing and treating disease,especially cancer nanovaccines,which have gained considerable interest recently for their strong anti-tumor immune capabilities.Vaccines can prompt the immune system to generate antibodies and activate various immune cells,leading to a response against tumor tissues and reducing the negative effects and recurrence risks of traditional chemotherapy and surgery.To enhance the flexibility and targeting of vaccines,nanovaccines utilize nanotechnology to encapsulate or carry antigens at the nanoscale level,enabling more controlled and precise drug delivery to enhance immune responses.Cancer nanovaccines function by encapsulating tumor-specific antigens or tumor-associated antigens within nanomaterials.The small size of these nanomaterials allows for precise targeting of T cells,dendritic cells,or cancer cells,thereby eliciting a more potent anti-tumor response.In this paper,we focus on the classification of carriers for cancer nanovaccines,the roles of different target cells,and clinically tested cancer nanovaccines,discussing strategies for effectively inducing cytotoxic T lymphocytes responses and optimizing antigen presentation,while also looking ahead to the translational challenges of moving from animal experiments to clinical trials.

Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development.Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function.Increasing amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers.These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases.Through a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

Cell polarization in ischemic stroke: molecular mechanisms and advances

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal cells.Moreover,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal cells.Cajal cells are the pacemakers of gastrointestinal motility.AIM To investigate the effects of Bifidobacterium lactis(B.lactis)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit pathway.METHODS The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 days.The tail group was given B.lactis BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/day.Hematoxylin&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and PCR.The fecal flora and mucosal flora of rats in each group were detected by 16S rRNA.RESULTS Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic intervention.Simulated microgravity reduced the expressions of SCF and c-kit,and increased the expressions of ERK and P-ERK in the gastric antrum of rats.However,after probiotic intervention,the expressions of SCF and ckit were increased,while the expressions of ERK and P-ERK were decreased,with statistical significance(P<0.05).In addition,simulated microgravity can reduce the operational taxonomic unit(OTU)of the overall intestinal flora of rats,B.lactis BLa80 can increase the OTU of rats,simulated microgravity can reduce the overall richness and diversity of stool flora of rats,increase the abundance of firmicutes in stool flora of rats,and reduce the abundance of Bacteroides in stool flora of rats,most of which are mainly beneficial bacteria.Simulated microgravity can increase the overall richness and diversity of mucosal flora,increase the abundance of Bacteroides and Desulphurides in the rat mucosal flora,and decrease the abundance of firmicutes,most of which are proteobacteria.After probiotics intervention,the overall Bacteroidetes trend in simulated microgravity rats was increased.CONCLUSION B.lactis BLa80 can ameliorate intestinal mucosal injury,regulate intestinal flora,inhibit ERK expression,and activate the SCF/c-kit signaling pathway,which may have a facilitating effect on gastrointestinal motility in simulated microgravity rats.

Signaling cross-talk between TGF-β/BMP and other pathways

Transforming growth factor-beta （TGF-β）/bone morphogenic protein （BMP） signaling is involved in the vast majority of cellular processes and is fundamentally important during the entire life of all metazoans. Deregulation of TGF-β/ BMP activity almost invariably leads to developmental defects and/or diseases, including cancer. The proper functioning of the TGF-β/BMP pathway depends on its constitutive and extensive communication with other signaling pathways, leading to synergistic or antagonistic effects and eventually desirable biological outcomes. The nature of such signaling cross-talk is overwhelmingly complex and highly context-dependent. Here we review the different modes of cross-talk between TGF-β/BMP and the signaling pathways of Mitogen-activated protein kinase, phosphatidylinositol-3 kinase/ Akt, Wnt, Hedgehog, Notch, and the interleukin/interferon-gamma/tumor necrosis factor-alpha cytokines, with an emphasis on the underlying molecular mechanisms.

MiR-146a-5p targeting SMAD4 and TRAF6 inhibits adipogenensis through TGF-β and AKT/mTORC1 signal pathways in porcine intramuscular preadipocytes

Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.

The molecular mechanism underlying angiogenesis in hepatocellular carcinoma: the imbalance activation of signaling pathways

OBJECTIVE: To explore the effect of two dominating signaling pathways, VEGF/KDR and angiopoietins/Tie2, on the formation of new blood vessel in hepatocellular carcinoma (HCC) growth and metastasis. METHODS: RT-PCR and Western blot were employed to evaluate the VEGF/KDR and angiopoietins/Tie2 expression in samples from 23 patients with HCC. Meanwhile, microvessel density (MVD) was determined as a marker of angiogenesis by counting CD34 positive cells with the method of immunohistochemistry. RESULTS: The two pathways were activated in all HCC samples. The expressions of vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang2) were significantly higher (P<0.05) in hepatocellular carcinoma tissues and the margin of the tumor than those in control groups, and so did CD34 positive cells. Although significant difference in the expression of kinase insert domain containing receptor (KDR) and Ang1/Tie2 was not observed in all groups, their distinct high levels were seen in hepatoma and its margin compared with normal and cirrhotic liver. VEGF and Ang2 expressions were seen up-regulated in HCC with vascular invasion and satellite lesion. CONCLUSIONS: The two signaling pathways, VEGF/KDR and angiopoietins/Tie2 are activated in the process of angiogenesis in HCC and modulate the formation of new blood vessels. The imparity of the two signaling pathways' activation is to benefit HCC metastasis. In the two pathways, VEGF and Ang2 may play an important role in the process of angiogenesis, and are necessary indicators for the prognosis and metastasis of HCC. This study provides another clue for the exploration of anti-angiogenic agents.