Unveiling the role of osteoblastic micro RNAs in the skeleton: from biological functions to therapeutic potential / Rol de los micro-ARN osteoblásticos en el esqueleto: desde las funciones biológicas al potencial terapéutico

MicroRNAs (miRNAs) are small non-coding RNA molecules that play critical roles in post-transcriptional gene regulation. They function by binding to target messenger RNA (mRNA) molecules, leading to their degradation or inhibiting their translation into proteins. In the context of skeletal diseases, such as osteoporosis, osteoarthritis, and bone metastasis, there is growing evidence osteoblastic miRNAs, are involved in the regulation of bone formation and maintenance.Osteoblasts are bone-forming cells responsible for synthesizing and depositing the extracellular matrix, which ultimately mineralizes to form bone tissue. Osteoblastic miRNAs modulate various aspects of osteoblast function, including proliferation, differentiation, mineralization, and apoptosis. Dysregulation of these miRNAs can disrupt the balance between bone formation and resorption, leading to skeletal diseases.The therapeutic implications of targeting osteoblastic miRNAs in skeletal diseases are significant. Modulating the expression levels of specific miRNAs holds promise for developing novel therapeutic strategies to enhance bone formation, prevent bone loss, and promote bone regeneration. Potential therapeutic approaches include the use of synthetic miRNA mimics to restore miRNA expression in diseases associated with miRNA downregulation or the use of anti-miRNA oligonucleotides to inhibit miRNA function in diseases associated with miRNA upregulation.miRNA-based therapies are still in the early stages of development, and further research is needed to fully understand the complexity of miRNA networks. Additionally, the delivery of miRNAs to specific target tissues and cells remains a challenge that needs to be addressed for effective clinical translation. Nonetheless, targeting osteoblastic miRNAs represents a promising avenue for future therapeutic interventions in skeletal diseases. (AU)

Los micro-ARNs (miARNss) son pequeños ARN no codificantes que desempeñan un papel fundamental en la regulación génica postranscripcional. Ejercen su función al unir-se a moléculas de ARN mensajero (ARNm), promoviendo su degradación e inhibiendo su traducción en proteínas. En el contexto de las enfermedades esqueléticas, como la osteoporosis, la osteoartritis y la metástasis ósea existe evidencia de que los miARNs osteoblásticos están involucrados en la regulación de la formación y del mantenimiento óseo. Los osteoblastos son células formadoras de hueso responsables de sintetizar y depositar la matriz extracelular, que finalmente se mineraliza para formar el hueso. Los miARNs derivados de osteoblastos modulan varios aspectos de la función de estas células, incluida la proliferación, diferenciación, mineralización y la apoptosis. La desregulación de estos miARNs puede alterar el equilibrio entre la formación y la resorción ósea, lo que lleva a enfermedades óseas. Las implicaciones terapéuticas de los miARNs osteoblásticos en enfermedades esqueléticas son significativas. La modulación de los niveles de expresión de miARNs específicos es prometedora para desarrollar nuevas estrate-gias terapéuticas a fin de mejorar la formación, prevenir la pérdida y promover la regeneración ósea. Los enfoques terapéuticos potenciales incluyen el uso de miméticos de miARNs para restaurar la expresión de miARNs o el uso de oligonucleótidos anti-miARNs para inhibir su función. Las terapias basadas en miARNs aún se encuentran en las primeras etapas de desarrollo. La administración de miARNs a las células y los tejidos específicos sigue siendo un desafío para lograr una aplicación clínica eficaz. (AU)

Mecanismos moleculares de la farmacorresistencia en el cáncer de mama y posibles estrategias para superar la resistencia: Una revisión de la literatura / Molecular mechanisms of drug resistance in breast cancer and potential strategies for overcoming resistance: A literature review

El cáncer de mama es la causa más común de muerte por cáncer en el mundo, y la resistencia a los medicamentos es una de las barreras más importantes para el éxito de la terapia de la enfermedad. Es fundamental tener una comprensión sólida de los procesos moleculares que impulsan la resistencia al tratamiento en el cáncer de mama para diseñar terapias dirigidas con el potencial de superar esta resistencia. Estos mecanismos son complejos y multifacéticos e incluyen la activación de vías de señalización que promueven la supervivencia y proliferación celular, la regulación positiva de las bombas de salida de fármacos, la aparición de células madre cancerosas y cambios genéticos y epigenéticos. Esta revisión de la literatura brinda una descripción general de estos mecanismos y analiza las posibles estrategias para superar la resistencia a los medicamentos en el cáncer de mama, incluido el uso de terapias dirigidas que se dirigen específicamente a las vías y los mecanismos involucrados en la resistencia a los medicamentos. La revisión también destaca la necesidad de más investigación para identificar estrategias efectivas para superar la resistencia a los medicamentos y mejorar los resultados del tratamiento en pacientes con cáncer de mama.

Breast cancer is the most common cause of death from cancer in the world, and drug resistance is one of the most significant barriers to successful therapy for the disease. It is critical to have a solid understanding of the molecular processes driving treatment resistance in breast cancer to design targeted therapies with the potential to overcome this resistance. These complex and multifaceted mechanisms include the activation of signaling pathways that promote cell survival and proliferation, the upregulation of drug efflux pumps, the emergence of cancer stem cells, and genetic and epigenetic changes. This literature review provides an overview of these mechanisms. It discusses potential strategies for overcoming drug resistance in breast cancer, including targeted therapies that specifically target the pathways and mechanisms involved in drug resistance. The review also highlights the need for further research to identify effective strategies for overcoming drug resistance and improving treatment outcomes in breast cancer patients.

Diacerein mitigates renal ischemia/reperfusion injury via inhibition of renal inflammation, dendritic cells maturation and apoptosis: the role of TLR4/NF-kB/NLRP3/IL-1beta signaling pathway / La diacereína mitiga la lesión por isquemia/reperfusión renal a través de la inhibición de la inflamación renal, la maduración de las células dendríticas y la apoptosis: el papel de la vía de señalización TLR4/NF-kB/NLRP3/IL-1beta

SUMMARY: One of the reasons for acute kidney damage is renal ischemia. Nevertheless, there are limited protective and therapeutic approaches for this problem. Diacerein is an anti-inflammatory drug characterized by numerous biological activities. We aimed to determine the ameliorative impact of diacerein on renal ischemia/reperfusion injury (I/R) condition, exploring the underlying mechanisms. Twenty-four male rats were allotted into four groups (n= 6): sham group; Diacerein (DIA) group; I/R group, in which a non-crushing clamp occluded the left renal pedicle for 45 min, and the right kidney was nephrectomized for 5 min before the reperfusion process; I/R + diacerein group, injected intraperitoneally with 50 mg diacerein/kg i.m 30 minutes prior to I/R operation. Ischemia/ reperfusion was found to affect renal function and induce histopathological alterations. The flow cytometry analysis demonstrated an elevated expression of innate and mature dendritic cells in I/R renal tissues. Moreover, upregulation in the expression of the inflammatory genes (TLR4, Myd88, and NLRP3), and overexpression of the pro-inflammatory cytokines (IL-1β), apoptotic (caspase-3) and pyroptotic (caspase-1) markers were observed in I/R-experienced animals. The aforementioned deteriorations were mitigated by pre-I/R diacerein treatment. Diacerein alleviated I/R-induced inflammation and apoptosis. Thus, it could be a promising protective agent against I/R.

La isquemia renal es una de los motivos del daño renal agudo. Sin embargo, los enfoques protectores y terapéuticos para este problema son limitados. La diacereína es un fármaco antiinflamatorio caracterizado por numerosas actividades biológicas. Nuestro objetivo fue determinar el impacto de mejora de la diacereína en la condición de lesión por isquemia/ reperfusión renal (I/R), explorando los mecanismos subyacentes. Veinticuatro ratas macho se distribuyeron en cuatro grupos (n= 6): grupo simulado; grupo de diacereína (DIA); grupo I/R, en el que una pinza no aplastante ocluyó el pedículo renal izquierdo durante 45 min, y el riñón derecho fue nefrectomizado durante 5 min antes del proceso de reperfusión; Grupo I/R + diacereína, inyectado por vía intraperitoneal con 50 mg de diacereína/kg i.m. 30 min antes de la operación I/R. Se encontró que la isquemia/ reperfusión afecta la función renal e induce alteraciones histopatológicas. El análisis de citometría de flujo demostró una expresión elevada de células dendríticas innatas y maduras en tejidos renales I/R. Además, se observó una regulación positiva en la expresión de los genes inflamatorios (TLR4, Myd88 y NLRP3) y una sobreexpresión de las citoquinas proinflamatorias (IL-1β), marcadores apoptóticos (caspasa-3) y piroptóticos (caspasa-1) en animales con experiencia en I/R. Los deterioros antes mencionados fueron mitigados por el tratamiento previo a la diacereína I/R. La diacereína alivió la inflamación y la apoptosis inducidas por I/R. Por lo tanto, podría ser un agente protector prometedor contra I/R.

New research advances in hypertrophic scar formation, prevention and treatment / 中华预防医学杂志

Scarring, naturally induced by fibroblasts(Fb) during wound healing, is an essential process in response to repair damaged tissue. Excessive Fb proliferation which produces the excessive collagen deposition, including increased extracellular matrix synthesis or insufficient decomposition, typically contributes to hypertrophic scar(HS) formation. Although exact mechanisms of HS are not yet fully understood, it is generally believed that dysfunction of Fb and regulation of signal pathways play an important role in HS formation. Biologically, Fb function is affected by various factors such as cytokines, extracellular matrix and itself. In addition, modifications of miRNA, ceRNA, lncRNA, peptides and histones participate in HS formation by affecting the biological function of Fb. Despite the clinical importance, very few therapeutic modalities are available to prevent HS. To achieve this, a deeper characterization of Fb is required to identify mechanisms of HS. To the aspect of HS prevention and treatment, we review recent findings, concentrating on Fb function and collagen secretion. The objective of this article is to frame the current understanding, gain the deeper insights into Fb function, and provide the more comprehensive cognition and perspective for prevention and treatment of HS.

Lenvatinib down-regulates IGF1R/Mek/Erk signaling pathway in the treatment of regorafenib-resistant hepatocellular carcinoma / 中华肿瘤杂志

Objective: To investigate the therapeutic effect and mechanism of lenvatinib on regorafenib-resistant hepatocellular carcinoma cells. Methods: CCK-8 and clone formation assay were used to observe the inhibitory effect of lenvatinib on the growth of hepatocellular carcinoma cells. Flow cytometry was used to detect the apoptosis of regorafenib-resistant hepatocellular carcinoma cells treated with lenvatinib. The expression levels of related proteins were detected by western blot and immunohistochemical staining. The inhibitory effect of lenvatinib on the tumor formation ability of regorafenib-resistant hepatocellular carcinoma cells in vivo was observed by subcutaneous tumor formation experiment in mice. Results: CCK-8 and clone formation assay showed that lenvatinib could inhibit the proliferation of regorafenib-resistant hepatocellular carcinoma cells. The number of clones of HepG2, SMMC7721 and regorafenib-resistant HepG2, SMMC7721 cells in lenvatinib group (120.67±11.06, 53.00±11.14, 55.00±9.54, 78.67±14.64) were all lower than those in control group (478.00±24.52, 566.00±27.87, 333.67±7.02, 210.00±12.77, all P<0.05). Flow cytometry showed that lenvatinib could promote apoptosis of regorafenib-resistant hepatocellular carcinoma cells, the apoptosis rates of HepG2, SMMC7721 and regorafenib-resistant HepG2, SMMC7721 cells in lenvatinib group [(12.30±0.70)%, (9.83±0.38)%, (15.90±1.32)%, (10.60±0.00)%] were all higher than those in control group [(7.50±0.87)%, (5.00±1.21)%, (8.10±1.61)%, (7.05±0.78)%, all P<0.05]. The apoptosis-related protein levels suggested that apoptosis was increased in the treatment of lenvatinib. The animal study showed that lenvatinib can inhibit the growth of regorafenib-resistant cells in vivo. Immunohistochemistry and western blot results showed that lenvatinib could down-regulate the abnormally activated IGF1R/Mek/Erk signaling pathway in regorafenib-resistant cells. Conclusion: Lenvatinib can reverse regorafenib resistance in hepatocellular carcinoma, possibly by down-regulating IGF1R/Mek/Erk signaling pathway.

Maresin1 inhibits the NF-κB/caspase-3/GSDME signaling pathway to alleviate hepatic ischemia-reperfusion injury / 中华肝脏病杂志

Objective: To investigate the role of Maresin1 (MaR1) in hepatic ischemia-reperfusion injury (HIRI). Methods: The HIRI model was established and randomly divided into a sham operation group (Sham group), an ischemia-reperfusion group (IR group), and a MaR1 ischemia-reperfusion group (MaR1+IR group). MaR1 80ng was intravenously injected into each mouse's tail veins 0.5h before anesthesia. The left and middle hepatic lobe arteries and portal veins were opened and clamped. The blood supply was restored after 1h of ischemia. After 6h of reperfusion, the mice were sacrificed to collect blood and liver tissue samples. The Sham's group abdominal wall was only opened and closed. RAW267.4 macrophages were administered with MaR1 50ng/ml 0.5h before hypoxia, followed by hypoxia for 8h and reoxygenation for 2h, and were divided into the control group, the hypoxia-reoxygenation group (HR group), the MaR1 hypoxia-reoxygenation group (MaR1 + HR group), the Z-DEVD-FMK hypoxia-reoxygenation group (HR+Z group), the MaR1 + Z-DEVD-FMK hypoxia-reoxygenation group (MaR1 + HR + Z group), and the Con group without any treatment. Cells and the supernatant above them were collected. One-way analysis of variance was used for inter-group comparisons, and the LSD-t test was used for pairwise comparisons. Results: Compared with the Sham group, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin (IL)-1β, and IL-18 in the IR group were significantly higher (P < 0.05), with remarkable pathological changes, while the level in the MaR1 + IR group was lower than before (P < 0.05), and the pathological changes were alleviated. Compared with the Con group, the HR group had higher levels of IL-1β and IL-18 (P < 0.05), while the MaR1 + HR group had lower levels of IL-1β and IL-18 (P < 0.05). Western blot showed that the expressions of caspase-3, GSDME, and GSDME-N were significantly higher in the HR group and IR group than in the other groups; however, the expression was lower following MaR1 pretreatment. The Z-DEVD-FMK exploration mechanism was inhibited by the expression of caspase-3 in HIRI when using MaR1. Compared with the HR group, the IL-1β and IL-18 levels and the expressions of caspase-3, GSDME, and GSDME-N in the HR + Z group were decreased (P < 0.05), while the expression of nuclear factor κB was increased, but following MaR1 pretreatment, nuclear factor κB was decreased. There was no significant difference in the results between the MaR1 + H/R group and the MaR1 + H/R + Z group (P > 0.05). Conclusion: MaR1 alleviates HIRI by inhibiting NF-κB activation and caspase-3/GSDME-mediated inflammatory responses.

Maackiain inhibits proliferation and promotes apoptosis of nasopharyngeal carcinoma cells by inhibiting the MAPK/Ras signaling pathway / 中国天然药物

Nasopharyngeal carcinoma (NPC) is the third most common malignancy with a high recurrence and metastasis rate in South China. Natural compounds extracted from traditional Chinese herbal medicines have been developed and utilized for the treatment of a variety of cancers with modest properties and slight side effects. Maackiain (MA) is a type of flavonoid that was first isolated from leguminous plants, and it has been reported to relieve various nervous system disorders and exert anti-allergic as well as anti-inflammatory effects. In this study, we demonstrated that MA inhibited proliferation, arrested cell cycle and induced apoptosis in nasopharyngeal carcinoma CNE1 and CNE2 cells in vitro and in vivo. The expression of the related proteins associated with these processes were consistent with the above effects. Moreover, transcriptome sequencing and subsequent Western blot experiments revealed that inhibition of the MAPK/Ras pathway may be responsible to the anti-tumor effect of MA on NPC cells. Therefore, the effects of MA and an activator of this pathway, tertiary butylhydroquinone (TBHQ), alone or combination, were investigated. The results showed TBHQ neutralized the inhibitory effects of MA. These data suggest that MA exerts its anti-tumor effect by inhibiting the MAPK/Ras signaling pathway and it has the potential to become a treatment for patients with NPC.

Bavachin induces apoptosis in colorectal cancer cells through Gadd45a via the MAPK signaling pathway / 中国天然药物

Bavachin is a dihydroflavonoid compound isolated from Psoralea corylifolia, and exhibits anti-bacterial, anti-inflammatory, anti-tumor and lipid-lowering activities. Recent attention has gradually drawn on bavachin-induced apoptosis in many human cancer cell lines. However, the anti-cancer effects and related mechanisms in colorectal cancer remain unknown. Here, we investigated the effects of bavachin on colorectal cancer in vivo and in vitro. The results showed that bavachin inhibited the proliferation of human colorectal cancer cells and induce apoptosis. These changes were mediated by activating the MAPK signaling pathway, which significantly up-regulated the expression of Gadd45a. Furthermore, Gadd45a silencing obviously attenuated bavachin-mediated cell apoptosis. Inhibition of the MAPK signaling pathway by JNK/ERK/p38 inhibitors also weakened the up-regulation of Gadd45a by bavachin. The anticancer effect of bavachin was also validated using a mouse xenograft model of human colorectal cancer. In conclusion, these findings suggest that bavachin induces the apoptosis of colorectal cancer cells through activating the MAPK signaling pathway.

Modulation of type I interferon signaling by natural products in the treatment of immune-related diseases / 中国天然药物

Type I interferon (IFN) is considered as a bridge between innate and adaptive immunity. Proper activation or inhibition of type I IFN signaling is essential for host defense against pathogen invasion, tumor cell proliferation, and overactive immune responses. Due to intricate and diverse chemical structures, natural products and their derivatives have become an invaluable source inspiring innovative drug discovery. In addition, some natural products have been applied in clinical practice for infection, cancer, and autoimmunity over thousands of years and their promising curative effects and safety have been well-accepted. However, whether these natural products are primarily targeting type I IFN signaling and specific molecular targets involved are not fully elucidated. In the current review, we thoroughly summarize recent advances in the pharmacology researches of natural products for their type I IFN activity, including both agonism/activation and antagonism/inhibition, and their potential application as therapies. Furthermore, the source and chemical nature of natural products with type I IFN activity are highlighted and their specific molecular targets in the type I IFN pathway and mode of action are classified. In conclusion, natural products possessing type I IFN activity represent promising therapeutic strategies and have a bright prospect in the treatment of infection, cancer, and autoimmune diseases.

mTORC1 signaling pathway regulates tooth repair / 国际口腔科学杂志·英文版

Tooth germ injury can lead to abnormal tooth development and even tooth loss, affecting various aspects of the stomatognathic system including form, function, and appearance. However, the research about tooth germ injury model on cellular and molecule mechanism of tooth germ repair is still very limited. Therefore, it is of great importance for the prevention and treatment of tooth germ injury to study the important mechanism of tooth germ repair by a tooth germ injury model. Here, we constructed a Tg(dlx2b:Dendra2-NTR) transgenic line that labeled tooth germ specifically. Taking advantage of the NTR/Mtz system, the dlx2b+ tooth germ cells were depleted by Mtz effectively. The process of tooth germ repair was evaluated by antibody staining, in situ hybridization, EdU staining and alizarin red staining. The severely injured tooth germ was repaired in several days after Mtz treatment was stopped. In the early stage of tooth germ repair, the expression of phosphorylated 4E-BP1 was increased, indicating that mTORC1 is activated. Inhibition of mTORC1 signaling in vitro or knockdown of mTORC1 signaling in vivo could inhibit the repair of injured tooth germ. Normally, mouse incisors were repaired after damage, but inhibition/promotion of mTORC1 signaling inhibited/promoted this repair progress. Overall, we are the first to construct a stable and repeatable repair model of severe tooth germ injury, and our results reveal that mTORC1 signaling plays a crucial role during tooth germ repair, providing a potential target for clinical treatment of tooth germ injury.

Study of the inflammatory activating process in the early stage of Fusobacterium nucleatum infected PDLSCs / 国际口腔科学杂志·英文版

Fusobacterium nucleatum (F. nucleatum) is an early pathogenic colonizer in periodontitis, but the host response to infection with this pathogen remains unclear. In this study, we built an F. nucleatum infectious model with human periodontal ligament stem cells (PDLSCs) and showed that F. nucleatum could inhibit proliferation, and facilitate apoptosis, ferroptosis, and inflammatory cytokine production in a dose-dependent manner. The F. nucleatum adhesin FadA acted as a proinflammatory virulence factor and increased the expression of interleukin(IL)-1β, IL-6 and IL-8. Further study showed that FadA could bind with PEBP1 to activate the Raf1-MAPK and IKK-NF-κB signaling pathways. Time-course RNA-sequencing analyses showed the cascade of gene activation process in PDLSCs with increasing durations of F. nucleatum infection. NFκB1 and NFκB2 upregulated after 3 h of F. nucleatum-infection, and the inflammatory-related genes in the NF-κB signaling pathway were serially elevated with time. Using computational drug repositioning analysis, we predicted and validated that two potential drugs (piperlongumine and fisetin) could attenuate the negative effects of F. nucleatum-infection. Collectively, this study unveils the potential pathogenic mechanisms of F. nucleatum and the host inflammatory response at the early stage of F. nucleatum infection.

Tooth number abnormality: from bench to bedside / 国际口腔科学杂志·英文版

Tooth number abnormality is one of the most common dental developmental diseases, which includes both tooth agenesis and supernumerary teeth. Tooth development is regulated by numerous developmental signals, such as the well-known Wnt, BMP, FGF, Shh and Eda pathways, which mediate the ongoing complex interactions between epithelium and mesenchyme. Abnormal expression of these crutial signalling during this process may eventually lead to the development of anomalies in tooth number; however, the underlying mechanisms remain elusive. In this review, we summarized the major process of tooth development, the latest progress of mechanism studies and newly reported clinical investigations of tooth number abnormality. In addition, potential treatment approaches for tooth number abnormality based on developmental biology are also discussed. This review not only provides a reference for the diagnosis and treatment of tooth number abnormality in clinical practice but also facilitates the translation of basic research to the clinical application.

Coordinated Regulation of Myelination by Growth Factor and Amino-acid Signaling Pathways / 神经科学通报·英文版

Myelin-forming oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS) are essential for structural and functional homeostasis of nervous tissue. Albeit with certain similarities, the regulation of CNS and PNS myelination is executed differently. Recent advances highlight the coordinated regulation of oligodendrocyte myelination by amino-acid sensing and growth factor signaling pathways. In this review, we discuss novel insights into the understanding of differential regulation of oligodendrocyte and Schwann cell biology in CNS and PNS myelination, with particular focus on the roles of growth factor-stimulated RHEB-mTORC1 and GATOR2-mediated amino-acid sensing/signaling pathways. We also discuss recent progress on the metabolic regulation of oligodendrocytes and Schwann cells and the impact of their dysfunction on neuronal function and disease.

Type III secretory protein SINC of Chlamydia psittaci promotes host cell autophagy by activating the MAPK/ERK signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effects of SINC, a secreted protein of Chlamydia psittaci, on autophagy of host cells and the role of MAPK/ERK signaling pathway in mediating SINC-induced autophagy.@*METHODS@#RAW 264.7 cells treated with recombinant SINC were examined for changes in expression levels of LC3-II, Beclin-1, phosphorylated and total ERK1/2 using Western blotting. The expression level of LC3 in the treated cells was detected using immunofluorescence analysis, and the formation of autophagosomes and autolysosomes was observed with transmission electron microscopy (TEM). The effect of pretreatment with U0126 (a specific ERK inhibitor) on the expression levels of LC3-II and Beclin-1 in RAW 264.7 cells exposed to different concentrations of SINC was examined using Western blotting, and LC3 puncta in the cells was detected with immunofluorescence analysis.@*RESULTS@#The expression levels of LC3-II and Beclin-1 were the highest in RAW 264.7 cells treated with 2 μg/mL SINC for 12h. Immunofluorescence analysis showed exposure to SINC significantly increased the number of cells containing LC3 puncta, where the presence of autophagosomes and autolysosomes was detected. Exposure to 2 μg/mL SINC for 15 min resulted in the most significant increase of the ratios of p-ERK1/2/ERK1/2 in RAW 264.7 cells. Pretreatment of the cells with U0126 prior to SINC exposure significantly decreased the ratio of p-ERK1/2/ERK1/2, lowered the expression levels of LC3-II and Beclin-1, and decreased LC3 aggregation in the cells.@*CONCLUSIONS@#SINC exposure can induce autophagy in RAW 264.7 cells by activating the MAPK/ERK signaling pathway.

Bushen Huoxue Fang improves recurrent miscarriage in mice by down-regulating the JAK2/STAT3 pathway / 南方医科大学学报

OBJECTIVE@#To investigate the efficacy of Bushen Huoxue Fang (BSHXF, a traditional Chinese medicine formula) for improving recurrent spontaneous abortion (RSA) in mice and the role of tyrosine kinase (JAK2) and transcriptional activator (STAT3) signaling pathway in its therapeutic mechanism.@*METHODS@#Female CBA/J mice were caged with male DBA/2 mice to establish RSA mouse models, which were randomly divided into model group, dydrogesterone group and BSHXF group, with the female mice caged with male BALB/c mice as the control group (n=6). From the first day of pregnancy, the mice were subjected to daily intragastric administration of BSHXF, dydrogesterone, or distilled water (in control and model groups) for 12 days. After the treatments, serum levels of antithrombin III (AT-III), activated protein C (APC), tissue plasminogen activator (t-PA), progesterone, human chorionic gonadotropin (HCG), and estradiol (E2) were detected in each group using ELISA. HE staining was used to observe the morphological changes of the endometrium of the mice. Western blotting was performed to determine the expressions of p-JAK2, p-Stat3 and Bcl-2 in the placenta of the mice.@*RESULTS@#Compared with the control mice, the mouse models of RSA showed a significantly increased embryo loss rate with decreased serum levels of AT-III, T-PA, progesterone, APC and HCG, increased placental expressions of p-JAK2, p-STAT3 and Bax, and decreased expression of Bcl-2 (P < 0.05). Treatments with BSHXF and dydrogesterone both increased serum levels of AT-III, t-PA and HCG in the mouse models; Serum APC level was significantly reduced in BSHXF group and serum progesterone level was significantly increased in dydrogesterone group (P < 0.05).@*CONCLUSION@#BSHXF can improve the prethrombotic state and inhibit cell apoptosis by downregulating the JAK2/STAT3 pathway to increase the pregnancy rate in mouse models of RSA.

Apolipoprotein E enhances migration of endometrial cancer cells byactivating the ERK/MMP9 signaling pathway / 南方医科大学学报

OBJECTIVE@#To study the role of apolipoprotein E (APOE) in regulating endometrial cancer metastasis and explore the signaling pathway in the regulatory mechanism.@*METHODS@#Human endometrial cancer cell line HEC-1B was transfected with a control siRNA (siCtrl) or a specific siRNA targeting APOE (siAPOE) or with either pEGFP-N1 plasmid or an APOEoverexpressing plasmid. The changes in migration, proliferation, apoptosis and cell cycle of the transfected cells were examined using wound healing assay, Transwell migration assay, MTT assay, flow cytometry, and Hoechst staining. The activity of the ERK/MMP9 signaling pathway in the transfected cells was assessed using RT-qPCR and Western blotting. The expression level of APOE in clinical specimens of endometrial cancer tissues were detected using immunohistochemistry and its correlation with differentiation of endometrial cancer tissues was analyzed.@*RESULTS@#Wound healing assay and Transwell migration assay showed that compared with those in siCtrl group, HEC-1B cells transfected with siAPOE showed significantly reduced migration ability (P < 0.05), whereas APOE overexpression significantly promoted the migration of the cells (P < 0.05). Neither APOE knockdown nor overexpression produced significant effects on HEC-1B cell proliferation as shown by MTT assay and flow cytometry. Hoechst staining revealed that transfection with siAPOE did not significantly affect apoptosis of HEC-1B cells. APOE knockdown obviously reduced and APOE overexpression enhanced ERK phosphorylation and MMP9 expression in HEC-1B cells (P < 0.05). Treatment with U0126 partially reversed the effects of APOE overexpression on ERK phosphorylation, migration and MMP9 expression in HEC-1B cells (P < 0.05). APOE is highly expressed in clinical samples of endometrial cancer tissues as compared with the adjacent tissues.@*CONCLUSION@#APOE is highly expressed in endometrial cancer tissues to promote cancer cell migration by enhancing ERK phosphorylation and MMP9 expression.

LASS2/TMSG1 overexpression inhibits proliferation and promotes apoptosis of human lung cancer A549 cells possibly by upregulating ceramide and p38 MAPK to activate a signaling cascade / 南方医科大学学报

OBJECTIVE@#To investigate the effects of LASS2/TMSG1 gene overexpression on proliferation and apoptosis of human lung cancer A549 cells and explore the possible mechanism.@*METHODS@#We examined LASS2/TMSG1 expression level in a previously constructed A549 cell line overexpressing LASS2/TMSG1 using Western blotting. The proliferation and apoptosis of the cells were detected using colony-forming assay, CCK-8 assay, Hoechst/PI double staining and flow cytometry. Fourteen nude mice were randomized into 2 groups (n=7) to receive subcutaneous injection of A549 cells with or without LASS2/TMSG1 overexpression on the back of the neck, and the cell proliferation in vivo was observed. The expression levels of p38 MAPK protein and p-p38 MAPK protein in the xenografts were detected with Western blotting. ELISA was used to detect the levels of ceramide and p38 MAPK protein in cultured A549 cell supernatants and the xenografts in nude mice.@*RESULTS@#Compared with the negative control cells, A549 cells with LASS2/TMSG1 overexpression had significantly lowered proliferation ability in vitro with increased early apoptosis rate (P < 0.05), and showed obvious growth inhibition after inoculation in nude mice(P < 0.05). Western blotting showed that in both cultured A549 cells and the xenografts in nude mice, LASS2/TMSG1 gene overexpression significantly increased the expression levels of p38 MAPK protein and p-p38 MAPK protein (P < 0.05); the results of ELISA also revealed significantly increased levels of ceramide and p38 MAPK protein in the cell supernatant andxenografts as well (P < 0.05).@*CONCLUSION@#Overexpression of LASS2/TMSG1 gene can significantly inhibit the proliferation and promote early apoptosis of human lung cancer A549 cells both in vitro and in vivo possibly by upregulating the expressions of ceramide and p38 MAPK protein to activate a signal transduction cascade.

Licochalcone A induces cell cycle arrest in human lung squamous carcinoma cells via the PI3K/Akt signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of licochalcone A (LCA) on the proliferation and cell cycle of human lung squamous carcinoma cells and explore its possible molecular mechanism.@*METHODS@#MTT assay was used to detect the changes in proliferation of H226 cells after treatment with different concentrations of LCA for 48 h, and the IC50 of LCA was calculated. Flow cytometry was used to analyze cell cycle changes in H226 cells treated with 10, 20, and 40 μmol/L LCA, and the expressions of cyclin D1, cyclin-dependent kinase CDK2 and CDK4, and p-PI3K, PI3K, p-Akt, and Akt in the treated cells were detected using Western blotting. The effect of intraperitoneal injection of LCA for 24 days on tumor volume and weight was assessed in a BALB/c-nu mouse model bearing lung squamous carcinoma xenografts.@*RESULTS@#MTT assay showed that LCA significantly decreased the viability of H226 cells with an IC50 of 28.3 μmol/L at 48 h. Flow cytometry suggested that LCA treatment induced obvious cell cycle arrest at the G1 phase. LCA treatment also significantly decreased the expressions of cyclin D1, CDK2, and CDK4, and inhibited the phosphorylation of PI3K and Akt in H226 cells. In the tumor-bearing mice, LCA treatment for 24 days significantly reduced the tumor volume and weight.@*CONCLUSION@#LCA is capable of inhibiting the proliferation and inducing cell cycle arrest in lung squamous carcinoma cells possibility by regulating the PI3K/Akt singling pathway.

Shikonin induces hepatocellular carcinoma cell apoptosis by suppressing PKM2/PHD3/HIF-1α signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the mechanism of shikonin-induced death of human hepatocellular carcinoma SMMC-7721 cells.@*METHODS@#Cultured SMMC-7721 cells and normal hepatocytes (L-02 cells) were treated with 4, 8, or 16 μmol/L shikonin, and the changes in cell viability was assessed using MTT assay. The levels of ATP and lactic acid in the cell cultures were detected using commercial kits. Co-immunoprecipitation and immunofluorescence staining were used to determine the relationship among pyruvate kinase M2 (PKM2), prolyl hydroxylase 3 (PHD3), and hypoxia-inducible factor-1α (HIF-1α). The expressions of PHD3, PKM2, HIF-1α, Bax, cleaved caspase-3, and Bcl-2 in SMMC-7721 cells were detected with Western blotting, and cell apoptosis was analyzed with annexin V-FITC/PI staining. The effects of RNA interference of PKM2 on PHD3 and HIF-1α expressions in SMMC-7721 cells were detected using Western blotting.@*RESULTS@#The IC50 of shikonin against SMMC-7721 and L-02 cells was 8.041 μmol/L and 31.75 μmol/L, respectively. Treatment with shikonin significantly inhibited the protein expressions of PKM2, HIF-1α and PHD3 and nuclear translocation of PKM2 and HIF-1α in SMMC-7721 cells. Coimmunoprecipitation and immunofluorescence staining confirmed that shikonin inhibited the formation of PKM2/PHD3/HIF-1α complex and significantly reduced the contents of lactic acid and ATP in SMMC-7721 cells (P < 0.05). The expressions of PHD3 and HIF-1α decreased significantly after PKM2 knockdown (P < 0.05). Shikonin treatment significantly increased the apoptosis rate, enhanced the expressions of Bax and cleaved caspase-3, and decreased Bcl-2 expression in SMMC-7721 cells (P < 0.05).@*CONCLUSIONS@#Shikonin induces apoptosis of SMMC-7721 cells possibly by inhibiting aerobic glycolysis through the PKM2/PHD3/HIF-1α signaling pathway to cause energy supply dysfunction in the cells.

Teriparatide regulates osteoblast differentiation in high-glucose microenvironment through the cAMP/PKA/CREB signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of teriparatide on the differentiation of MC3T3-E1 cells in high-glucose microenvironment and explore the possible mechanism.@*METHODS@#MC3T3-E1 cells cultured in normal glucose or high-glucose (25 mmol/L) medium were treated with 10 nmol/L teriparatide with or without co-treatment with H-89 (a PKA inhibitor). CCK-8 assay was used to detect the changes in cell proliferation, and cAMP content in the cells was determined with ELISA. Alkaline phosphatase (ALP) activity and mineralized nodules in the cells were detected using ALP kit and Alizarin red staining, respectively. The changes in cell morphology were detected by cytoskeleton staining. Real-time PCR was used to detect the mRNA expressions of PKA, CREB, RUNX2 and Osx in the treated cells.@*RESULTS@#The treatments did not result in significant changes in proliferation of MC3T3-E1 cells (P > 0.05). Compared with the cells in routine culture, the cells treated with teriparatide showed significantly increased cAMP levels (P < 0.05) with enhanced ALP activity and increased area of mineralized nodules (P < 0.05). Teriparatide treatment also resulted in more distinct visualization of the cytoskeleton in the cells and obviously up-regulated the mRNA expressions of PKA, CREB, RUNX2 and Osx (P < 0.05). The opposite changes were observed in cells cultured in high glucose. In cells exposed to high glucose, treatment with teriparatide significantly increased cAMP levels (P < 0.05), ALP activity and the area of mineralized nodules (P < 0.05) and enhanced the clarity of the cytoskeleton and mRNA expressions of PKA, CREB, RUNX2 and Osx; the effects of teriparatide was strongly antagonized by co-treatment with H-89 (P < 0.05).@*CONCLUSION@#Teriparatide can promote osteoblast differentiation of MC3T3-E1 cells in high-glucose microenvironment possibly by activating the cAMP/PKA/CREB signaling pathway.