The C-terminus of the prototypical M2 muscarinic receptor localizes to the mitochondria and regulates cell respiration under stress conditions.

Muscarinic acetylcholine receptors are prototypical G protein-coupled receptors (GPCRs), members of a large family of 7 transmembrane receptors mediating a wide variety of extracellular signals. We show here, in cultured cells and in a murine model, that the carboxyl terminal fragment of the muscarinic M2 receptor, comprising the transmembrane regions 6 and 7 (M2tail), is expressed by virtue of an internal ribosome entry site localized in the third intracellular loop. Single-cell imaging and import in isolated yeast mitochondria reveals that M2tail, whose expression is up-regulated in cells undergoing integrated stress response, does not follow the normal route to the plasma membrane, but is almost exclusively sorted to the mitochondria inner membrane: here, it controls oxygen consumption, cell proliferation, and the formation of reactive oxygen species (ROS) by reducing oxidative phosphorylation. Crispr/Cas9 editing of the key methionine where cap-independent translation begins in human-induced pluripotent stem cells (hiPSCs), reveals the physiological role of this process in influencing cell proliferation and oxygen consumption at the endogenous level. The expression of the C-terminal domain of a GPCR, capable of regulating mitochondrial function, constitutes a hitherto unknown mechanism notably unrelated to its canonical signaling function as a GPCR at the plasma membrane. This work thus highlights a potential novel mechanism that cells may use for controlling their metabolism under variable environmental conditions, notably as a negative regulator of cell respiration.

Rab2A regulates the progression of nonalcoholic fatty liver disease downstream of AMPK-TBC1D1 axis by stabilizing PPARγ.

Nonalcoholic fatty liver disease (NAFLD) affects approximately a quarter of the population worldwide, and persistent overnutrition is one of the major causes. However, the underlying molecular basis has not been fully elucidated, and no specific drug has been approved for this disease. Here, we identify a regulatory mechanism that reveals a novel function of Rab2A in the progression of NAFLD based on energy status and PPARγ. The mechanistic analysis shows that nutrition repletion suppresses the phosphorylation of AMPK-TBC1D1 signaling, augments the level of GTP-bound Rab2A, and then increases the protein stability of PPARγ, which ultimately promotes the hepatic accumulation of lipids in vitro and in vivo. Furthermore, we found that blocking the AMPK-TBC1D1 pathway in TBC1D1S231A-knock-in (KI) mice led to a markedly increased GTP-bound Rab2A and subsequent fatty liver in aged mice. Our studies also showed that inhibition of Rab2A expression alleviated hepatic lipid deposition in western diet-induced obesity (DIO) mice by reducing the protein level of PPARγ and the expression of PPARγ target genes. Our findings not only reveal a new molecular mechanism regulating the progression of NAFLD during persistent overnutrition but also have potential implications for drug discovery to combat this disease.

KIAA1429 Induces m6A Modification of LINC01106 to Enhance the Malignancy of Lung Adenocarcinoma Cells via the JAK/STAT3 Pathway.

BACKGROUND: Sustained expression of the long noncoding RNA (lncRNA) LINC01106 in tumors is crucial for the malignant phenotype of tumor cells. Nevertheless, the mechanisms and clinical effects of LINC01106 in lung adenocarcinoma (LUAD) are limited. This study shows the effect of vir-like m6A methyltransferase-associated (KIAA1429)-mediated N6-methyladenosine (m6A) modification on steady LINC01106 expression on LUAD progression. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine LINC01106 and KIAA1429 levels in LUAD tissues. Transwell, 5-ethynyl-2'-deoxyuridine (EdU), and cell counting kit-8 (CCK-8) assays were used to analyze the functional roles of LINC01106. A xenograft was constructed to verify the function of silencing LINC01106 in tumor growth. The regulatory role of LINC01106 was investigated using methylated RNA immunoprecipitation (MeRIP), qRT-PCR, and the actinomycin D assay. Western blotting was used to identify key proteins in the JAK/STAT3 (JAK2, STAT3) pathway. RESULTS: LINC01106 and KIAA1429 were highly expressed in LUAD, and LINC01106 was interconnected with high tumor grade, stage, and poor prognosis. Data revealed that LINC01106 inhibition reduced LUAD cell proliferation, invasion, and migration and restrained LUAD cell tumorigenicity. In addition, LINC01106 silencing reduced phosphorylated JAK2 and STAT3 levels. KIAA1429-mediated LINC01106 enhances its m6A modification and expression in LUAD cells. Moreover, KIAA1429 promotion eliminated the malignant phenotypic suppression induced by low expression in LUAD cells. CONCLUSION: This study showed that KIAA1429 enhanced LINC01106 m6A modification to promote LUAD development. These results may lead to a better understanding of the mechanism of KIAA1429-m6A-LINC01106 in LUAD and offer a valuable therapeutic target for LUAD.

MEN1 is a regulator of alternative splicing and prevents R-loop-induced genome instability through suppression of RNA polymerase II elongation.

The fidelity of alternative splicing (AS) patterns is essential for growth development and cell fate determination. However, the scope of the molecular switches that regulate AS remains largely unexplored. Here we show that MEN1 is a previously unknown splicing regulatory factor. MEN1 deletion resulted in reprogramming of AS patterns in mouse lung tissue and human lung cancer cells, suggesting that MEN1 has a general function in regulating alternative precursor mRNA splicing. MEN1 altered exon skipping and the abundance of mRNA splicing isoforms of certain genes with suboptimal splice sites. Chromatin immunoprecipitation and chromosome walking assays revealed that MEN1 favored the accumulation of RNA polymerase II (Pol II) in regions encoding variant exons. Our data suggest that MEN1 regulates AS by slowing the Pol II elongation rate and that defects in these processes trigger R-loop formation, DNA damage accumulation and genome instability. Furthermore, we identified 28 MEN1-regulated exon-skipping events in lung cancer cells that were closely correlated with survival in patients with lung adenocarcinoma, and MEN1 deficiency sensitized lung cancer cells to splicing inhibitors. Collectively, these findings led to the identification of a novel biological role for menin in maintaining AS homeostasis and link this role to the regulation of cancer cell behavior.

Contact-electro-catalysis (CEC).

Contact-electro-catalysis (CEC) is an emerging field that utilizes electron transfer occurring at the liquid-solid and even liquid-liquid interfaces because of the contact-electrification effect to stimulate redox reactions. The energy source of CEC is external mechanical stimuli, and solids to be used are generally organic as well as in-organic materials even though they are chemically inert. CEC has rapidly garnered extensive attention and demonstrated its potential for both mechanistic research and practical applications of mechanocatalysis. This review aims to elucidate the fundamental principle, prominent features, and applications of CEC by compiling and analyzing the recent developments. In detail, the theoretical foundation for CEC, the methods for improving CEC, and the unique advantages of CEC have been discussed. Furthermore, we outline a roadmap for future research and development of CEC. We hope that this review will stimulate extensive studies in the chemistry community for investigating the CEC, a catalytic process in nature.

Reversal in Output Current Direction of 4H-SiC/Cu Tribovoltaic Nanogenerator as Controlled by Relative Humidity.

Tribovoltaic nanogenerators (TVNG) represent a fantastic opportunity for developing low-frequency energy harvesting and self-powered sensing, by exploiting their real-time direct-current (DC) output. Here, a thorough study of the effect of relative humidity (RH) on a TVNG consisting of 4H-SiC (n-type) and metallic copper foil (SM-TVNG) is presented. The SM-TVNG shows a remarkable sensitivity to RH and an abnormal RH dependence. When RH increases from ambient humidity up to 80%, an increasing electrical output is observed. However, when RH rises from 80% to 98%, the signal output not only decreases, but its direction reverses as it crosses 90% RH. This behavior differs greatly from that of a Si-based TVNG, whose output constantly increases with RH. The behavior of the SM-TVNG might result from the competition between the built-in electric field induced by metal-semiconductor contact and a strong triboelectric electric field induced by solid-liquid triboelectrification under high RH. The authors also demonstrated that both SM-TVNG and Si-based TVNG can work effectively as-is even fully submerged in deionized water. This mechanism can affect other devices and be applied to design self-powered sensors working under high RH or underwater.

Piezocatalysis for Chemical-Mechanical Polishing of SiC: Dual Roles of t-BaTiO3 as a Piezocatalyst and an Abrasive.

Chemical mechanical polishing (CMP) offers a promising pathway to smooth third-generation semiconductors. However, it is still a challenge to reduce the use of additional oxidants or/and energy in current CMP processes. Here, a new and green atomically smoothing method: Piezocatalytic-CMP (Piezo-CMP) is reported. Investigation shows that the Piezo-CMP based on tetragonal BaTiO3 (t-BT) can polish the rough surface of a reaction sintering SiC (RS-SiC) to the ultra-smooth surface with an average surface roughness (Ra) of 0.45 nm and the rough surface of a single-crystal 4H-SiC to the atomic planarization Si and C surfaces with Ra of 0.120 and 0.157 nm, respectively. In these processes, t-BT plays a dual role of piezocatalyst and abrasive. That is, it piezo-catalytically generates in-situ active oxygen species to selectively oxidize protruding sites of SiC surface, yielding soft SiO2, and subsequently, it acts as a usual abrasive to mechanically remove these SiO2. This mechanism is further confirmed by density functional theory (DFT) calculation and molecular simulation. In this process, piezocatalytic oxidation is driven only by the original pressure and friction force of a conventional polishing process, thus, the piezo-CMP process do not require any additional oxidant and energy, being a green and effective polishing method.

Analysis of Risk Factors for Recurrence after Transurethral Resection of Bladder Tumor in Patients with Non-Muscle Invasive Bladder Cancer: 2-Year Follow-Up Outcomes.

INTRODUCTION: The aim was to investigate the risk factors for recurrence after transurethral resection of bladder tumor (TURBT) in patients with non-muscle invasive bladder cancer (NMIBC) and to provide a basis for clinical prevention of recurrence of NMIBC. METHODS: From January 2012 to December 2020, 592 patients with NMIBC who underwent TURBT attending the Second Affiliated Hospital of Xi'an Jiaotong University were retrospectively included in this study. Patients were divided into relapse and relapse-free groups according to whether relapse occurred within 2 years. Ultimately, 72 patients were included in the relapse group and 350 patients were included in the relapse-free group. Observation indicators included age, sex, smoking, underlying disease (hypertension, diabetes, coronary heart disease), two or more lesions, tumor size, hematuria, pathology grading (low, medium, high), staging (Ta, T1), muscular invasion in initial pathology, tumor base (sessile, pedunculated), use of intravesical drug (pirarubicin, bacillus Calmette-Guerin [BCG], mitomycin, hydroxycamptothecin, gemcitabine). RESULTS: In this study, the 2-year recurrence rate of NMIBC patients after TURBT was 17.06%. There were significant differences in comparison of pirarubicin, BCG, and mitomycin treatment between the two groups (p < 0.05). To avoid missing risk factors for recurrence, factors with p < 0.1 were analyzed. The results of univariate logistic regression analysis showed that NMIBC patients with BCG treatment (OR = 5.088, 95% CI = 1.444-17.73, p = 0.012), high pathology grading (OR = 0.415, 95% CI = 0.197-0.880, p = 0.023), T1 stage (OR = 2.097, 95% CI = 0.996-4.618, p = 0.059), mitomycin treatment (OR = 5.029, 95% CI = 1.149-21.77, p = 0.031), and pirarubicin treatment (OR = 1.794, 95% CI = 1.079-3.030, p = 0.024) had significantly higher risk of recurrence within 2 years after TURBT. The results of multivariate logistic regression analysis showed that NMIBC patients with high pathology grading (OR = 0.4030, 95% CI = 0.1702-0.8426, p = 0.0241), pirarubicin treatment (OR = 1.961, 95% CI = 1.159-3.348, p = 0.0125), and BCG treatment (OR = 6.201, 95% CI = 1.275-29.73, p = 0.0190) had significantly higher risk of recurrence within 2 years after TURBT. CONCLUSION: Our study highlights the importance of postoperative surveillance and individualized treatment for patients with NMIBC. Our findings show that high pathology grading, pirarubicin treatment, and BCG treatment are independent risk factors for recurrence after TURBT in patients with NMIBC. However, caution is warranted when interpreting our findings due to the small sample size and the need for further research to confirm the negative impact of mitomycin and BCG on recurrence rates.

HDAC1 Promotes Mitochondrial Pathway Apoptosis and Inhibits the Endoplasmic Reticulum Stress Response in High Glucose-Treated Schwann Cells via Decreased U4 Spliceosomal RNA.

Dysfunction of Schwann cells, including cell apoptosis, autophagy inhibition, dedifferentiation, and pyroptosis, is a pivotal pathogenic factor in induced diabetic peripheral neuropathy (DPN). Histone deacetylases (HDACs) are an important family of proteins that epigenetically regulate gene transcription by affecting chromatin dynamics. Here, we explored the effect of HDAC1 on high glucose-cultured Schwann cells. HDAC1 expression was increased in diabetic mice and high glucose-cultured RSC96 cells, accompanied by cell apoptosis. High glucose also increased the mitochondrial pathway apoptosis-related Bax/Bcl-2 and cleaved caspase-9/caspase-9 ratios and decreased endoplasmic reticulum response-related GRP78, CHOP, and ATF4 expression in RSC96 cells (P < 0.05). Furthermore, overexpression of HDAC1 increased the ratios of Bax/Bcl-2, cleaved caspase-9/caspase-9, and cleaved caspase-3 and reduced the levels of GRP78, CHOP, and ATF4 in RSC96 cells (P < 0.05). In contrast, knockdown of HDAC1 inhibited high glucose-promoted mitochondrial pathway apoptosis and suppressed the endoplasmic reticulum response. Moreover, RNA sequencing revealed that U4 spliceosomal RNA was significantly reduced in HDAC1-overexpressing RSC96 cells. Silencing of U4 spliceosomal RNA led to an increase in Bax/Bcl-2 and cleaved caspase-9 and a decrease in CHOP and ATF4. Conversely, overexpression of U4 spliceosomal RNA blocked HDAC1-promoted mitochondrial pathway apoptosis and inhibited the endoplasmic reticulum response. In addition, alternative splicing analysis of HDAC1-overexpressing RSC96 cells showed that significantly differential intron retention (IR) of Rpl21, Cdc34, and Mtmr11 might be dominant downstream targets that mediate U4 deficiency-induced Schwann cell dysfunction. Taken together, these findings indicate that HDAC1 promotes mitochondrial pathway-mediated apoptosis and inhibits the endoplasmic reticulum stress response in high glucose-cultured Schwann cells by decreasing the U4 spliceosomal RNA/IR of Rpl21, Cdc34, and Mtmr11.

Thin-Film Composite Membranes Interlayered with Amphiphilic MoS2 Nanosheets via Controllable Interfacial Polymerization for Enhanced Desalination Performance.

Polyamide (PA)-based nanofiltration (NF) membranes have demonstrated extensive applications for a sustainable water-energy-environment nexus. A rational control of interfacial polymerization (IP) is highly efficacious to enhance NF separation performance yet remains a technical challenge. Herein, we proposed a regulation strategy of constructing amphiphilic molybdenum disulfide/cetyltrimethylammonium bromide interlayer atop the Kevlar hydrogel substrate. The amphiphilic nanosheet interlayered NF membrane exhibited a crumpled PA surface with an elevated cross-linking degree of 76.9%, leading to an excellent water permeance (16.8 L m-2 h-1 bar-1) and an impressive Na2SO4 rejection (99.1%). Meanwhile, the selectivity coefficient of Na2SO4/NaCl of the optimized TFC membrane reached 91, surpassing those of the recently reported NF membranes. Moreover, the optimized membrane exhibited a desirable rejection of over 90% against Mn2+ and Cu2+ in actual textile wastewater. Importantly, the underlying NF membrane formation mechanism was elucidated via both experiments and molecular simulations. The synchronous control of mass and heat transfer of IP process offers a new methodology for the state-of-the-art membrane fabrication, which opens more avenues in softening of brackish water and purification of industrial wastewater containing heavy metal ions.

A Novel NIR Fluorescence Probe with AIE Property to Image Viscosity in Nystatin-Induced Cell Model.

As one of the most significant parameters in cellular microenvironment, viscosity levels could be used to determine the metabolic process of bioactive substances within cells. Abnormal viscosity levels are closely associated with a series of diseases. Therefore, the design and synthesis of fluorescent probes that can monitor changes of intracellular viscosity in real-time is of great significance for the study of disease development process. Here, a new viscosity-recognized NIR fluorescence probe W1 based on quinoline-malonitrile is synthesized, and it is not susceptible to interference substances. Besides, AIE probe W1 shows fast response, excellent photostability, low cytotoxicity, good linear relationship between fluorescence intensity value and viscosity. Based on the above advantages, probe W1 is used to image the change of viscosity level in the cell model induced by nystatin.

A new strategy for the treatment of Parkinson's disease: Discovery and bio-evaluation of the first central-targeting tyrosinase inhibitor.

The high level of tyrosinase leads to the generation of neuromelanin, further causing the abnormality of redox-related protein level and mediating the occurrence and development of Parkinson's disease (PD). However, the existing tyrosinase inhibitors are mostly natural product extracts or polyphenolic derivatives, which hindered them from penetrating the blood-brain barrier (BBB). Herein, we obtained a novel tyrosinase inhibitor, 2-06 (tyrosinase: monophenolase IC50 = 70.44 ± 22.69 µM, diphenolase IC50 = 1.89 ± 0.64 µM), through the structure-based screening method. The compound 2-06 presented good in vitro and in vivo safety, and can inhibit the tyrosinase and melanogenesis in B16F10. Moreover, this compound showed neuroprotective effects and Parkinsonism behavior improving function. 2-06 was proved to penetrate the BBB and enter the central nervous system (CNS). The exploration of the binding mode between 2-06 and tyrosinase provided the foundation for the subsequent structural optimization. This is the first research to develop a central-targeting tyrosinase inhibitor, which is crucial for in-depth study on the new strategy for utilizing tyrosinase inhibitors to treat PD.

Silencing circSERPINE2 restrains mesenchymal stem cell senescence via the YBX3/PCNA/p21 axis.

Increasing evidence indicates that circular RNAs (circRNAs) accumulate in aging tissues and nonproliferating cells due to their high stability. However, whether upregulation of circRNA expression mediates stem cell senescence and whether circRNAs can be targeted to alleviate aging-related disorders remain unclear. Here, RNA sequencing analysis of differentially expressed circRNAs in long-term-cultured mesenchymal stem cells (MSCs) revealed that circSERPINE2 expression was significantly increased in late passages. CircSERPINE2 small interfering RNA delayed MSC senescence and rejuvenated MSCs, while circSERPINE2 overexpression had the opposite effect. RNA pulldown followed by mass spectrometry revealed an interaction between circSERPINE2 and YBX3. CircSERPINE2 increased the affinity of YBX3 for ZO-1 through the CCAUC motif, resulting in the sequestration of YBX3 in the cytoplasm, inhibiting the association of YBX3 with the PCNA promoter and eventually affecting p21 ubiquitin-mediated degradation. In addition, our results demonstrated that senescence-related downregulation of EIF4A3 gave rise to circSERPINE2. In vivo, intra-articular injection of si-circSerpine2 restrained native joint-resident MSC senescence and cartilage degeneration in mice with aging-related osteoarthritis. Taken together, our findings provide strong evidence for a regulatory role for the circSERPINE2/YBX3/PCNA/p21 axis in MSC senescence and the therapeutic potential of si-circSERPINE2 in alleviating aging-associated syndromes, such as osteoarthritis.

Optimization of Bear Oil Extraction Process and Hair Growth Activity.

According to ancient Chinese books, bear grease has the effects of strengthening muscles and bones, which is beneficial for weakness, but there is relatively little research on it. Thus, the extraction of it is beneficial for compensating for research in this area. In this study, a uniform experimental design method was used to optimize the extraction process of bear grease by enzymatic hydrolysis extraction, and the extraction rate can reach 81.89% under optimized extraction conditions. Furthermore, the components of bear grease obtained by this study were analyzed by GC-MS, and the results showed that ursolic oil was rich in unsaturated fatty acids (67.51%), which was higher than that of the traditional method (66.92%). The composition of bear grease extracted by the enzymatic method was also better than that extracted by the traditional method. In addition, bear grease obtained in this study had the obvious activity of promoting hair growth. The length, weight, and number of hair follicles in the depilation area of mice in the high-dose group were significantly different from those in the blank group (p < 0.01). This study optimized the extraction process of bear grease and conducted a preliminary analysis of its fatty acid composition, which is expected to provide some reference for the development of the medicinal value of bear grease.

In situ and Real-time Monitoring the Chemical and Thermal Evolution of Lithium-ion Batteries with Single-crystalline Ni-rich Layered Oxide Cathode.

High-capacity Ni-rich layered oxides are promising cathode materials for fabrication of lithium-ion batteries (LIBs) with high energy density. However, thermal runaway of LIBs with these cathodes leads to great safety concerns. In this study, single crystalline LiNi0.9Co0.05Mn0.05O2 (NCM-SC) has been prepared and a flexible optical fiber was buried inside the pouch-type LIBs with NCM-SC cathode to in situ study its real-time temperature evolution during charge/discharge process. NCM-SC exhibits an enhanced Li+ ions transportation efficiency and electrode reaction kinetics, which can effectively reduce the generation of polarization heat and mitigate the internal temperature rise of the pouch-type battery. Meanwhile, solid-electrolyte interface (SEI) film decomposition and gas accumulation are effectively alleviated, due to the enhanced thermal stability of SEI film formed on NCM-SC. Moreover, the single crystal architecture can effectively retard layered to spinal and rock-salt phase transition, mitigate the crack formation and structural collapse. Consequently, NCM-SC exhibits an excellent electrochemical performance and enhanced thermal stability.

Efficacy and safety of immune checkpoint inhibitors in Proficient Mismatch Repair (pMMR)/ Non-Microsatellite Instability-High (non-MSI-H) metastatic colorectal cancer: a study based on 39 cohorts incorporating 1723 patients.

PURPOSE: This study was designed to investigate the efficacy and safety of immune checkpoint inhibitors (ICIs)-based therapy in proficient mismatch repair (pMMR)/non-microsatellite instability-high (non-MSI-H) metastatic colorectal cancer (mCRC). METHODS: Electronic databases were screened to identify relevant trials. The primary endpoints were pooled objective response rate (ORR) and disease control rate (DCR). Stratified analysis was accomplished on ICIs-based regimens, treatment lines and RAS status. RESULTS: Totally, 1723 mCRC patients from 39 cohorts were included. The pooled ORR, DCR, 12-month overall survival (OS) rate and 6-month progression-free survival (PFS) rate of ICIs-based therapy in pMMR/non-MSI-H mCRC were 8.5% (95% CI: 4.4%-13.5%), 48.2% (95% CI: 37.8%-58.6%), 52.3% (95% CI: 46.4%-58.1%) and 32.8% (95% CI: 23.5%-42.7%) respectively. As a whole, no significantly differences were shown between ICIs-based and non-ICIs-based therapy for pMMR/non-MSI-H mCRC in terms of both PFS (HR = 1.0, 95% CI: 0.9-1.1, P = 0.91) and OS (HR = 1.0, 95% CI: 0.9-1.2, P = 0.51). It was worth noting that the addition of ICIs to anti-vascular endothelial growth factor (VEGF) agent plus chemotherapy displayed excellent efficacy in pMMR/non-MSI-H mCRC (ORR = 42.4%, 95% CI: 10.0%-78.6%; DCR = 92.0%, 95% CI: 68.3%-100.0%; 12-month OS rate = 71.4%, 95% CI: 50.0%-89.1%; 6-month PFS rate = 55.2%, 95% CI: 24.8%-83.8%; and PFS (compared with non-ICIs-based therapy): HR = 0.9, 95% CI: 0.8-1.0, P = 0.02), especially served as first-line therapy (ORR = 74.2%, 95% CI: 61.4%-85.4%; DCR = 98.7%, 95% CI: 92.0%-100.0%); and without additional treatment related adverse events (TRAEs) were observed. CONCLUSIONS: ICIs-based combination therapy, especially the addition of ICIs to first-line anti-VEGF agent plus chemotherapy, is promising in pMMR/non-MSI-H mCRC with good efficacy and controllable toxicity.

Bone marrow mesenchymal stem cells paracrine TGF-ß1 to mediate the biological activity of osteoblasts in bone repair.

BACKGROUND: Bone marrow mesenchymal stem cells (BMSCs) are an important source of seed cells for regenerative medicine and tissue engineering therapy. BMSCs have multiple differentiation potentials and can release paracrine factors to facilitate tissue repair. Although the role of the osteogenic differentiation of BMSCs has been fully confirmed, the function and mechanism of BMSC paracrine factors in bone repair are still largely unclear. This study aimed to determine the roles of transforming growth factor beta-1 (TGF-ß1) produced by BMSCs in bone tissue repair. METHODS: To confirm our hypothesis, we used a Transwell system to coculture hBMSCs and human osteoblast-like cells without contact, which could not only avoid the interference of the osteogenic differentiation of hBMSCs but also establish the cell-cell relationship between hBMSCs and human osteoblast-like cells and provide stable paracrine substances. In the transwell coculture system, alkaline phosphatase activity, mineralized nodule formation, cell migration and chemotaxis analysis assays were conducted. RESULTS: Osteogenesis, migration and chemotaxis of osteoblast-like cells were regulated by BMSCs in a paracrine manner via the upregulation of osteogenic and migration-associated genes. A TGF-ß receptor I inhibitor (LY3200882) significantly antagonized BMSC-induced biological activity and related gene expression in osteoblast-like cells. Interestingly, coculture with osteoblast-like cells significantly increased the production of TGF-ß1 by BMSCs, and there was potential intercellular communication between BMSCs and osteoblast-like cells. CONCLUSIONS: Our findings provide evidence that the biological mechanism of BMSC-produced TGF-ß1 promotes bone regeneration and repair, providing a theoretical basis and new directions for the application of BMSC transplantation in the treatment of osteonecrosis and bone injury.

DAPK1 Interacts with the p38 Isoform MAPK14, Preventing Its Nuclear Translocation and Stimulation of Bone Marrow Adipogenesis.

Bone marrow (BM) adipose tissue (BMAT), a unique adipose depot, plays an important role in diseases such as osteoporosis and bone metastasis. Precise control of mesenchymal stem cell (MSC) differentiation is critical for BMAT formation and regeneration. Here, we show that death associated protein kinase 1 (DAPK1) negatively regulates BM adipogenesis in vitro and in vivo. Prx1creDapk1loxp/loxp mice showed more adipocytes in the femur than Dapk1loxp/loxp mice. Further mechanistic analyses revealed that DAPK1 inhibits p38 mitogen-activated protein kinase (MAPK) signaling in the nucleus by binding the p38 isoform MAPK14, decreasing p38 nuclear activity, which subsequently inhibits BM adipogenesis. The inhibitory effect of DAPK1 against MAPK14 was independent of its kinase activity. In addition, the decreased DAPK1 was observed in the BM-MSCs of ageing mice. Our results reveal a previously undescribed function for DAPK1 in the regulation of adipogenesis and may also reveal the underlying mechanism of BMAT formation in ageing.

The active phthalate metabolite, DHEP, induces proliferation and metastasis of prostate cancer cells via upregulation of ß-catenin and downregulation of KLF7.

Phthalates such as DHEP are among the widely used compounds in industry. It has been shown that DHEP can convey various biological consequences in mammalian cells, among them, the carcinogenic effects of DHEP are emphasized. The present study aimed to assess the impact of DHEP exposure on the proliferation and invasiveness of DU145 prostate cancer cells through in vitro and in vivo models. The DU145 cells were treated with increasing concentrations of DHEP and the tumorigenic parameters were analyzed. KLF7 as a probable mediator of the effect of DHEP was either overexpressed or knocked down in DU145 to evaluate the probable impact of KLF7 on the biological effects of DHEP. The effect of DHEP was also studied in a DU145 xenograft tumor model. The moderate doses of DHEP increased the proliferation and migration of DU145 cells. In the case of gene expression patterns, DHEP reduced the levels of p53 and KLF7 while elevated the expression of ß-catenin. The knock-down of KLF7 conveyed comparable effects to that of DHEP to some degree and increased the proliferation of DU145 cells, while the transduction of KLF7 increased the expressions of p53 and p21 along with controlling the tumor size. The present study demonstrated the potential of DHEP in increasing the tumorigenic properties of DU145 cells along with a focus on the underlying mechanisms. Sustained exposure to DHEP can cause a dysregulation in balance between oncogenes and tumor suppressor genes which is the hallmark of malignant transformation. Thus, special considerations seem necessary for the safe exploitation of phthalates.

Lipid metabolism-related miRNAs with potential diagnostic roles in prostate cancer.

BACKGROUND: Prostate cancer (PCa), the second most prevalent solid tumor among men worldwide, has caused greatly increasing mortality in PCa patients. The effects of lipid metabolism on tumor growth have been explored, but the mechanistic details of the association of lipid metabolism disorders with PCa remain largely elusive. METHODS: The RNA sequencing data of the GSE45604 and The Cancer Genome Atlas-Prostate Adenocarcinoma (TCGA-PRAD) datasets were extracted from the Gene Expression Omnibus (GEO) and UCSC Xena databases, respectively. The Molecular Signatures Database (MSigDB) was utilized to identify lipid metabolism-related genes. The limma R package was used to identify differentially expressed lipid metabolism-related genes (DE-LMRGs) and differentially expressed microRNAs (DEMs). Moreover, least absolute shrinkage and selection operator (LASSO), extreme gradient boosting (XGBoost), and support vector machine-recursive feature elimination (SVM-RFE) were applied to select signature miRNAs and construct a lipid metabolism-related diagnostic model. The expression levels of selected differentially expressed lipid metabolism-related miRNAs (DE-LMRMs) in PCa and benign prostate hyperplasia (BPH) specimens were verified using quantitative real-time polymerase chain reaction (qRT‒PCR). Furthermore, a transcription factor (TF)-miRNA‒mRNA network was constructed. Eventually, Kaplan‒Meier (KM) curves were plotted to illustrate the associations between signature miRNA-related mRNAs and TFs and overall survival (OS) along with biochemical recurrence-free survival (BCR). RESULTS: Forty-seven LMRMs were screened based on the correlation analysis of 29 DE-LMRGs and 56 DEMs, in which 27 LMRMs were stably expressed in the GSE45604 dataset. Subsequently, receiver operating characteristic (ROC) curves and machine learning methods were employed to develop a lipid metabolism-related diagnostic signature, which may be of diagnostic value for PCa patients. qRT‒PCR results showed that all seven key DE-LMRMs were differentially expressed between PCa and BPH tissues. Eventually, a TF-miRNA‒mRNA network was constructed. CONCLUSIONS: These results suggested that 7 key diagnostic miRNAs were closely related to PCa pathological processes and provided new targets for the diagnosis and treatment of PCa. Moreover, CLIC6 and SCNN1A linked to miR-200c-3p had good prognostic potential and provided valuable insights into the pathogenesis of PCa.