Luciferase Reporter Assay Research Articles

Echinacoside inhibits hepatocellular carcinoma progression by targeting the miR-30c-5p/FOXD1/KLF12 axis.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-attributed mortality and the primary liver malignancy in the world. Echinacoside is a phenylethanoid glycoside derived from traditional Chinese medicinal herbs which possessed multiple health benefits on humans, including anti-tumor effects. This study aimed to demonstrate the function of echinacoside in HCC progression and the involvement of miR-30c-5p/FOXD1/KLF12 axis. The HepG2 cells were treated by different dose of echinacoside, miR-30c-5p mimic, miR-30c-5p inhibitor, and FOXD1 overexpression lentiviruses or siRNA individually or simultaneously. The cell invasion and migration were measured by transwell assay. RNA and protein levels were tested by RT-PCR and western blot, respectively. The regulatory function of miR-30c-5p on Forkhead box D1 (FOXD1), FOXD1 on Krüppel-like factor 12 (KLF12) was tested by luciferase reporter assay or/and ChIP assay. Meanwhile, a liver cancer lung metastasis mice model was used to examine the functions of echinacoside and miR-30c-5p on HCC metastasis in vivo. Moreover, the correlations among miR-30c-5p, FOXD1, KLF12, and HCC prognosis was analyzed using clinical sample and TCGA database. Based on both in vitro and in vivo investigations, we found that echinacoside could inhibit HCC cell migration, invasiveness, and tumor metastasis, and associated with the enhanced miR-30c-5p/FOXD1/KLF12 axis. Furthermore, through analyzing the interactions among intermediate molecules, we revealed that miR-30c-5p, FOXD1, and KLF12üere clinically relevant with each other in HCC patients, correlated with HCC prognosis, and regulated by echinacoside to contribute in the inhibition of HCC progression. These findings suggest that echinacoside could inhibit HCC progression, and the mechanism related to the enhanced miR-30c-5p/FOXD1/KLF12 axis. Moreover, the abovementioned intermediate molecules might serve as prospective biomarkers for HCC prognosis.

Luciferase Reporter Assay for Determining the Signaling Activity of Interferons.

The classic dual luciferase reporter assay has been widely used to rapidly and accurately determine the transcriptional activity of a given promoter induced by certain signal pathways in the cells. In particular, the sensitive characteristics of luciferase highlight its significance in many experiments, such as weak promoter analysis, transfection studies using small amounts of DNA, and detection in cell lines with low transfection efficiency. This chapter presents detailed information and experimental procedures for measuring interferon (IFN)-induced Interferon-Stimulated Response Element (ISRE) promoter activity using the dual luciferase reporter assay.

TRPM2-AS promotes ovarian cancer cell proliferation and inhibits cell apoptosis by upregulating the nearby gene TRPM2 via miR-6764-5p

Ovarian cancer (OC) becomes a fatal gynecologic malignant cancer in females worldwide. Target therapy is a promising therapeutical choice for patients with OC, and identifying biomarkers and exploring molecular mechanisms are necessary. In this study, the functions and mechanism of long noncoding RNA transient receptor potential cation channel subfamily M member 2 antisense RNA (TRPM2-AS) in OC were explored. TRPM2-AS expression in OC cells was analyzed utilizing reverse transcription quantitative polymerase chain reaction (RT-qPCR). Cell counting kit-8 (CCK-8) and colony forming assays were carried out to explore the influence of TRPM2-AS on OC cell viability and proliferation. Cell apoptosis was detected using TdT-mediated dUTP Nick-End labeling (TUNEL) and flow cytometry analysis. Protein expression of apoptotic markers was subjected to western blotting. RNA pulldown or luciferase reporter assays were applied to explore the interaction between TRPM2-AS and miR-6764-5p or the binding of miR-6764-5p and TRPM2. The results showed that TRPM2-AS is highly expressed in OC cells and was mainly localized in cytoplasm. TRPM2-AS depletion suppressed OC cell viability and proliferation while increasing cell apoptotic rate. TRPM2 displayed a high level in OC cells and was positively regulated by TRPM2-AS. TRPM2-AS interacted with miR-6764-5p and thereby upregulated TRPM2 expression. In addition, TRPM2 overexpression reversed the repressive impact of TRPM2-AS depletion on malignant OC cellular process. In conclusion, TRPM2-AS promotes OC cell viability and proliferation while enhancing cell apoptosis through interaction with miR-6764-5p to regulate TRPM2 level.

Epigenetic regulation of thyroid hormone action in human metabolic dysfunction-associated steatohepatitis.

Metabolic dysfunction-associated steatohepatitis (MASH) is characterized by inflammation, fibrosis, and accumulation of fatty acids in the liver. MASH disease progression has been associated with reduced thyroid hormone (TH) signaling in the liver, including reduced expression of deiodinase type I (DIO1) and TH receptor beta (THRB). However, the underlying mechanisms mediating these effects remain elusive. Here, we hypothesized that epigenetic mechanisms may be involved in modulating hepatic TH action. Liver samples from patients with and without MASH were analyzed by qRT-PCR and correlated with clinical parameters. Luciferase reporter assays and overexpression of miRNA in HepG2 cells were used to validate the functional binding of miRNA to predicted targets. DNA methylation was analyzed by bisulfite pyrosequencing. miR-34a-5p was upregulated in MASH patients and correlated positively with the clinical parameters of MASH. Using in silico and in vitro analysis, we demonstrate that miR-34a-5p is capable of targeting several modulators of local hepatic TH action, as evidenced by the functional binding of miR-34a-5p to the seed sequence in the THRB and DIO1 genes. Consequently, overexpression of miR-34a-5p in HepG2 cells reduced the expression of THRA, THRB, DIO1, and SLC10A1, thus potentially mediating an acquired hepatic resistance to TH in MASH. As an additional regulatory mechanism, DNA methylation of THRB intron 1 was increased in MASH and negatively correlated with THRB expression. miR-34a-5p constitutes a possible epigenetic master regulator of hepatic TH action, which together with THRB-specific DNA methylation could explain a possible developing TH resistance in the liver during MASH progression on the molecular level.

PDCD4 interacting with PIK3CB and CTSZ promotes the apoptosis of multiple myeloma cells.

The role of programmed cell death 4 (PDCD4) in multiple myeloma (MM) development remains unknown. Here, we investigated its role and action mechanism in MM. Bioinformatic analysis indicated that patients with MM and high PDCD4 expression had higher overall survival than those with low PDCD4 expression. PDCD4 expression promoted MM cell apoptosis and inhibited their viability invitro and tumor growth invivo. RNA-binding protein immunoprecipitation sequencing analysis showed that PDCD4 is bound to the 5' UTR of the apoptosis-related genes PIK3CB, Cathepsin Z (CTSZ), and X-chromosome-linked apoptosis inhibitor (XIAP). PDCD4 knockdown reduced the cell apoptosis rate, which was rescued by adding PIK3CB, CTSZ, or XIAP inhibitors. Dual luciferase reporter assays confirmed the internal ribosome entry site (IRES) activity of the 5' UTRs of PIK3CB and CTSZ. An RNA pull-down assay confirmed binding of the 5' UTR of PIK3CB and CTSZ to PDCD4, identifying the specific binding fragments. PDCD4 is expected to promote MM cell apoptosis by binding to the IRES domain in the 5' UTR of PIK3CB and CTSZ and inhibiting their translation. Our findings suggest that PDCD4 plays an important role in MM development by regulating the expression of PIK3CB, CTSZ, and XIAP, and highlight new potential molecular targets for MM treatment.

Betaine delays age-related muscle loss by mitigating Mss51-induced impairment in mitochondrial respiration via Yin Yang1.

Mitochondrial dysfunction is one of the hallmarks of aging and a leading contributor to sarcopenia. Nutrients are essential for improving mitochondrial function and skeletal muscle health during the aging process. Betaine is a nutrient with potential muscle-preserving properties. However, whether and how betaine could regulate the mitochondria function in aging muscle are poorly understood. We aimed to explore the molecular target and underlying mechanism of betaine in attenuating the age-related mitochondrial dysfunction in skeletal muscle. Young mice (YOU, 2months), old mice (OLD, 15months), and old mice with betaine treatment (BET, 15months) were fed for 12weeks. The effects of betaine on muscle mass, strength, function, and subcellular structure of muscle fibres were assessed. RNA sequencing (RNA-seq) was conducted to identify the molecular target of betaine. The impacts of betaine on mitochondrial-related molecules, superoxide accumulation, and oxidative respiration were examined using western blotting (WB), immunofluorescence (IF) and seahorse assay. The underlying mechanism of betaine regulation on the molecular target to maintain mitochondrial function was investigated by luciferase reporter assay, chromatin immunoprecipitation and electrophoretic mobility shift assay. Adenoassociated virus transfection, succinate dehydrogenase staining (SDH), and energy expenditure assessment were performed on 20-month-old mice for validating the mechanism in vivo. Betaine intervention demonstrated anti-aging effects on the muscle mass (P=0.017), strength (P=0.010), and running distance (P=0.013). Mitochondrial-related markers (ATP5a, Sdha, and Uqcrc2) were 1.1- to 1.5-fold higher in BET than OLD (all P≤0.036) with less wasted mitochondrial vacuoles accumulating in sarcomere. Bioinformatic analysis from RNA-seq displayed pathways related to mitochondrial respiration activity was higher enriched in BET group (NES=-0.87, FDR=0.10). The quantitative real time PCR (qRT-PCR) revealed betaine significantly reduced the expression of a novel mitochondrial regulator, Mss51 (-24.9%, P=0.002). In C2C12 cells, betaine restored the Mss51-mediated suppression in mitochondrial respiration proteins (all P≤0.041), attenuated oxygen consumption impairment, and superoxide accumulation (by 20.7%, P=0.001). Mechanically, betaine attenuated aging-induced repression in Yy1 mRNA expression (BET vs. OLD: 2.06 vs. 1.02, P=0.009). Yy1 transcriptionally suppressed Mss51 mRNA expression both in vitro and in vivo. This contributed to the preservation of mitochondrial respiration, improvement for energy expenditure (P=0.008), and delay of muscle loss during aging process. Altogether, betaine transcriptionally represses Mss51 via Yy1, improving age-related mitochondrial respiration in skeletal muscle. These findings suggest betaine holds promise as a dietary supplement to delay skeletal muscle degeneration and improve age-related mitochondrial diseases.

SUMO3 inhibition by butyric acid suppresses cell viability and glycolysis and promotes gemcitabine antitumor activity in pancreatic cancer

BackgroundExcavation of key molecules can help identify therapeutic targets and improve the prognosis of pancreatic cancer. This study evaluated the roles of SUMO3 in cell viability, glycolysis, gemcitabine (GEM) sensitivity, and the antitumor activity of butyric acid (BA) in pancreatic cancer.MethodsThe mRNA and protein levels of SUMO3 were detected by qRT-PCR, Western blot, and immunohistochemical assay. SUMO3 was silenced or overexpressed in pancreatic cancer cells with or without Wnt/β-catenin pathway inhibitor, glycolysis inhibitor, GEM, or BA treatment. Cell viability was measured using the Cell Counting Kit-8 assay. Glycolysis was measured by determining the extracellular acidification rate, ATP level, and lactate content. Apoptosis was measured by flow cytometry, and TUNEL staining was used to examine in vitro and in vivo sensitivity to GEM chemotherapy. Luciferase reporter and chromatin immunoprecipitation assays were conducted to detect the binding of the SUMO3 promoter and NF-κB p65.ResultsSUMO3 was increased and associated with poor survival in pancreatic cancer. SUMO3 knockdown decreased cell viability and glycolysis in vitro and inhibited tumor growth in vivo. SUMO3 overexpression increased cell viability and glycolysis in vitro through the β-catenin pathway. SUMO3 knockdown increased GEM sensitivity, whereas SUMO3 overexpression decreased GEM sensitivity and inhibited the antitumor activity of BA. BA promoted histone acetylation and p-IκBα expression to inhibit NF-κB p65-mediated SUMO3 transcription.ConclusionSUMO3 acted as an active molecule in cell survival and growth by enhancing glycolysis in response to either GEM or BA. The mechanism was related to the constitutive IκBα/NF-κB/SUMO3/β-catenin signaling pathway.

Exosomal LINC00958 maintains ovarian cancer cell stemness and induces M2 macrophage polarization via Hedgehog signaling pathway and GLI1 protein

Long non-coding RNA (lncRNA) LINC00958 has been reported to promote many gynecological cancers, but its detailed function in OC remains unclear. Cancer stem cells (CSCs) and tumor-associated macrophages (TAMs) have been reported to participate in the occurrence and metastasis of cancers. We want to explore the effects of exosomal LINC00958 on cell stemness and macrophage polarization in OC. LINC00958 expression was first verified in OC cells and its function on cell stemness was verified by subcellular fractionation analysis, sphere formation assay and so on. Exosomal LINC00958 was secreted from OC cells and the model of M2 macrophage polarization was established to further verify the impact of exosomal LINC00958 on the cell stemness and macrophage polarization of OC cells using several mechanism experiments including flow cytometry, RNA pulldown, luciferase reporter assays and so on. LINC00958 was up-regulated in OC cells and exosomal LINC00958 enhanced the stem cell-like properties of OC cells and M2 macrophage polarization. Furthermore, LINC00958 combined with glioma-associated oncogene homolog 1 (GLI1) to activate Hedgehog pathway, thereby promoting M2 polarization. Exosomal LINC00958 maintained OC cell stemness and induced M2 polarization via the Hedgehog signaling pathway.

TaNAC1 boosts powdery mildew resistance by phosphorylation-dependent regulation of TaSec1a and TaCAMTA4 via PP2Ac/CDPK20.

The integrity of wheat (Triticum aestivum) production is increasingly jeopardized by the fungal pathogen Blumeria graminis f. sp. tritici (Bgt), particularly amid the vicissitudes of climate change. Here, we delineated the role of a wheat transcription factor, TaNAC1, which precipitates cellular apoptosis and fortifies resistance against Bgt. Utilizing BiFC, co-immunoprecipitation, protein quantification, luciferase report assays, we determined that cytoplasmic TaNAC1-7A undergoes phosphorylation at the S184/S258 sites by TaCDPK20, facilitating its nuclear translocation. This migration appears to prime further phosphorylation by TaMPK1, thereby enhancing transcriptional regulatory activity. Notably, the apoptotic activity of phosphorylated TaNAC1-7A is negatively modulated by the nuclear protein phosphatase PP2Ac. Furthermore, activation of TaNAC1 phosphorylation initiates transcription of downstream genes TaSec1a and TaCAMTA4, through binding to the C[T/G]T[N7]A[A/C]G nucleic acid motif. Suppression of TaNAC1, TaCDPK20, and TaMPK1 in wheat compromises its resistance to Bgt strain E09, whereas overexpression of TaNAC1 and silencing of PP2Ac markedly elevate resistance levels. Our results reveal the pivotal role of TaNAC1 in basal resistance which is mediated by its effects on homotypic fusion, vacuolar protein sorting, and the expression of defense-related genes. The findings highlight the potential through targeting TaNAC1 and its regulators as a strategy for improving wheat's resistance to fungal pathogens.

STRIP2 is regulated by the transcription factor Sp1 and promotes lung adenocarcinoma progression via activating the PI3K/AKT/mTOR/MYC signaling pathway

BackgroundPatients with lung adenocarcinoma (LUAD) generally have poor prognosis. The role of striatin-interacting protein 2 (STRIP2) in LUAD remain unclear. MethodsLiquid chromatography-mass spectrometry analyses were used to screen the STRIP2-binding proteins and co-immunoprecipitation verified these interactions. A dual luciferase reporter assay explored the transcription factor activating STRIP2 transcription. Xenograft and lung metastasis models assessed STRIP2's role in tumor growth and metastasis in vivo. ResultsSTRIP2 is highly expressed in LUAD tissues and is linked to poor prognosis. STRIP2 expression in LUAD cells significantly promoted cell proliferation, invasion, and migration in vitro and in vivo. Mechanistically, STRIP2 boosted the PI3K/AKT/mTOR/MYC cascades by binding AKT. In addition, specificity protein 1, potently activated STRIP2 transcription by binding to the STRIP2 promoter. Blocking STRIP2 reduces tumor growth and lung metastasis in xenograft models. ConclusionsOur study identifies STRIP2 is a key driver of LUAD progression and a potential therapeutic target.

Inhibitory Effects of Naringenin on LPS-Induced Skin Inflammation by NF-κB Regulation in Human Dermal Fibroblasts.

Flavonoids are important natural compounds characterized by their extensive biological activities. Citrus flavonoids represent a significant segment of the broader flavonoid category. Naringenin, an integral part of this series, is recognized for its powerful anti-inflammatory and antioxidant properties. In addition, considering the lack of existing research on naringenin's potential effectiveness and intracellular mechanisms of action in skin-related applications, especially as a cosmetic ingredient, this study aimed to explore naringenin's role in reducing the fundamental generation of reactive oxygen species. This was achieved by examining its inhibitory effects on the expression levels of NADPH oxidase and iNOS, ultimately leading to a reduction in NO production. This research examined the anti-inflammatory and antioxidant capacities of naringenin by employing a cellular senescence model of LPS-induced HDFs. The evaluation of naringenin's efficacy was validated through several investigative procedures, including the NF-κB luciferase assay, ELISA assay, and qRT-PCR. To verify the anti-inflammatory effectiveness of naringenin, we measured the responsive elements of NF-κB using a luciferase reporter assay. This assessment revealed that naringenin could decrease the concentration of genes activated by NF-κB. Moreover, we found that naringenin inhibited the transcriptional expression of known NF-κB-regulated inflammatory cytokines, including IL-1β, IL-6, and IL-8. In addition, results from the qRT-PCR analysis indicated that naringenin facilitated a reduction in iNOS expression. Based on the data gathered and analyzed in this study, it can be conclusively inferred that naringenin possesses promising potential as a cosmetic ingredient, offering both anti-inflammatory and antioxidant benefits.

RNA-binding protein LSM7 facilitates breast cancer metastasis through mediating alternative splicing of CD44

AimsThe RNA-binding protein LSM7 is essential for RNA splicing, acting as a key component of the spliceosome complex; however, its specific role in breast cancer (BC) has not been extensively investigated. Materials and methodsLSM7 expression in BC samples was evaluated through bioinformatics analysis and immunohistochemistry. The impact of LSM7 on promoting metastatic tumor characteristics was examined using transwell and wound healing assays, as well as an orthotopic xenograft model. Additionally, the involvement of LSM7 in alternative splicing of CD44 was explored via RNA immunoprecipitation and third-generation sequencing. The regulatory role of TCF3 in modulating LSM7 gene expression was further elucidated using luciferase reporter assays and chromatin immunoprecipitation. Key findingsOur findings demonstrate that LSM7 was significantly overexpressed in metastatic BC tissues and was associated with poor prognostic outcomes in patients with BC. LSM7 overexpression markedly increased the migratory and invasive capabilities of BC cells in vitro and significantly promoted spontaneous lung metastasis in vivo. Furthermore, RIP-seq analysis revealed that LSM7 binded to CD44 RNA, enhancing the expression of its alternatively spliced isoform CD44s, thereby driving BC metastasis and invasion. Additionally, the transcription factor TCF3 was found to activate LSM7 transcription by directly binding to its promoter. SignificanceIn summary, this study highlights the pivotal role of LSM7 in the production of the CD44s isoform and the promotion of breast cancer metastasis. Targeting the TCF3/LSM7/CD44s axis may offer a promising therapeutic strategy for breast cancer treatment.

Transcriptional activation of SIRT5 by FOXA1 reprograms glycolysis to facilitate the malignant progression of diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) is the most common diagnosed subtype of lymphoma with high invasiveness and heterogeneity. Glycolysis is involved in regulating DLBCL progression. We aimed to explore the role of forkhead box protein A1 (FOXA1) in DLBCL and the mechanisms related to sirtuine5 (SIRT5) and glycolysis. FOXA1 expression in DLBCL cells was analyzed. Then, the proliferation and apoptosis of DLBCL cells were detected using Cell Counting Kit-8 (CCK-8), 5-ethynyl-2′-deoxyuridine (EDU) staining and flow cytometry analysis following FOXA1 or SIRT5 knockdown. The glycolysis was assessed by measuring extracellular acidification rate (ECAR), glucose consumption and lactate secretion. Immunoblotting was employed to examine the expression of apoptosis- and glycolysis-related proteins. Additionally, luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay were conducted to test the combination of FOXA1 to SIRT5 promotor region. Subsequently, SIRT5 expression was upregulated to conduct rescue assays. Finally, the effects of FOXA1 downregulation on the growth and glycolysis in OCI-ly7 tumor-bearing mice were examined. As a result, FOXA1 was upregulated in DLBCL cells and FOXA1 or SIRT5 knockdown inhibited the proliferation, accelerated the apoptosis and suppressed glycolysis reprograming in DLBCL cells. Importantly, FOXA1 could transcriptionally activate SIRT5 expression in DLBCL cells. Besides, SIRT5 overexpression counteracted the effects of FOXA1 deficiency on the proliferation, apoptosis and glycolysis reprogramming in DLBCL cells. Furthermore, FOXA1 knockdown inhibited the tumor growth, suppressed the glycolysis reprogramming and downregulated SIRT5 expression in vivo. In summary, FOXA1 could transcriptionally activate SIRT5 to reprogram glycolysis, thereby facilitating the malignant progression of DLBCL.

Overexpression of microRNA-611 inhibits TGF-β-induced epithelial-mesenchymal transition and migration in lung cancer cells through MAPKAP1

Metastasis is a major cause of death in patients with lung cancer (LC). microRNA-611 (miR-611), a miRNA, has been little studied in cancer. Here, we aimed to further elucidate the roles of miR-611 in epithelial-mesenchymal transition (EMT) and migration induced by transforming growth factor-β (TGF-β) in LC cells and the possible underlying mechanisms. miR-611 and MAPKAP1 expression was first identified in LC tissues from metastatic and nonmetastatic patients, and their expression was associated with overall survival. Gain- and loss-of-function experiments were performed to verify the impacts of miR-611 and MAPKAP1 on pAKT expression, EMT, and migration in LC cells treated with TGF-β. The interaction between miR-611 and MAPKAP1 was also determined with a luciferase reporter assay. In our study, miR-611 was expressed at low levels, and MAPKAP1 was highly expressed in LC tissues, which was associated with metastasis and short overall survival. Functionally, miR-611 inhibition or MAPKAP1 overexpression accelerated EMT and migration and upregulated pAKT in TGF-β-treated A549 and H1299 cells; miR-611 overexpression or MAPKAP1 silencing exerted the opposite effects as miR-611 inhibition or MAPKAP1 overexpression. Mechanistically, miR-611 could target and downregulate MAPKAP1. MAPKAP1 expression was also negatively correlated with miR-611 expression in LC tissues. In addition, miR-611 overexpression reduced the EMT and migration of TGF-β-treated A549 and H1299 cells by targeting MAPKAP1. In conclusion, miR-611 overexpression attenuated EMT and migration by targeting MAPKAP1 in TGF-β-induced LC cells, indicating that miR-611 is a biological target for LC treatment.

MicroRNAs modulate SARS-CoV-2 infection of primary human hepatocytes by regulating the entry factors ACE2 and TMPRSS2.

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) preferentially infects the respiratory tract; however, several studies have implicated a multi-organ involvement. Hepatic dysfunctions caused by SARS-CoV-2 infection have been increasingly recognized and described to correlate with disease severity. To elucidate molecular factors that could contribute towards hepatic infection, we concentrated on microRNAs (miRNAs), a class of small non-coding RNAs that modulate various cellular processes and which are reported to be differentially regulated during liver injury. We aimed to study the infection of primary human hepatocytes (PHH) with SARS-CoV-2 and to evaluate the potential of miRNAs for modulating viral infection. We analysed liver autopsies from a coronavirus disease 19 (COVID-19)-positive cohort for the presence of viral RNA using Nanopore sequencing. PHH were used for the infection with SARS-CoV-2. The candidate miRNAs targeting angiotensin converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) were identified using in silico approaches. To discover the potential regulatory mechanism, transfection experiments, qRT-PCRs, western blots and luciferase reporter assays were performed. We could detect SARS-CoV-2 RNA in COVID-19-positive liver autopsies. We show that PHH express ACE2 and TMPRSS2 and can be readily infected with SARS-CoV-2, resulting in robust replication. Transfection of selected miRNA mimics reduced SARS-CoV-2 receptor expression and SARS-CoV-2 burden in PHH. In silico and biochemical analyses supported a potential direct binding of miR-141-3p to the SARS-CoV-2 genome. We confirm that PHH are susceptible to SARS-CoV-2 infection and demonstrate selected miRNAs targeting SARS-CoV-2 entry factors and/or the viral genome reduce viral loads. These data provide novel insights into hepatic susceptibility to SARS-CoV-2 and associated dysfunctions in COVID-19.

Molecular characterization of cassava zinc finger-homeodomain (ZF-HD) transcription factors reveals their role in disease resistance

The production of cassava (Manihot esculenta Crantz) is constantly threatened by cassava bacterial blight (CBB), caused by Xanthomonas phaseoli pv. manihotis (Xpm). Zinc finger-homeodomain (ZF-HD) belongs to a family of homozygous heterotypic cassette genes widely implicated in various developmental and physiological processes in plants. Despite their importance, a comprehensive analysis of ZF-HD genes, particularly those involved in disease resistance, has not been performed for cassava. In the present study, we utilized bioinformatics methods to identify 21 ZF-HD genes distributed across 11 chromosomes of cassava genome, with the majority exhibiting gene structure without introns. Phylogenetic analysis categorized these genes into two major groups (MIF and ZHD) with five subgroups. We observed fourteen pairs of duplicated genes, suggesting that segmental duplication has likely facilitated the expansion of the cassava ZF-HD gene family. Comparative orthologous analyses between cassava and other plant species shed light on the evolutionary trajectory of this gene family. Promoter analyses revealed multiple hormone- and stress-related elements, indicative of a functional role in stress responses. Expression profiling through RNA-seq and quantitative real-time PCR (qRT-PCR) demonstrated that certain cassava ZF-HD genes are up-regulated in response to Xpm infection, suggesting their involvement in defense mechanisms. Notably, MeZHD7 gene was identified via virus induced gene silencing (VIGS) as potentially crucial in conferring resistance against CBB. Results from subcellular localization experiments indicated that MeZHD7 was localized in the nucleus. The Luciferase reporter assay demonstrated an interaction between MeZHD7 and MeMIF5. These findings may lay the foundation for further cloning and functional analyses of cassava ZF-HD genes, particularly those associated with pathogen resistance.

LncRNA HAGLR regulates gastric cancer progression by regulating the miR-20a-5p/E2F1 axis.

Gastric cancer (GC) stands as a prevalent and challenging malignancy within the gastrointestinal tract. The potential of long non-coding RNAs (lncRNAs) as biomarkers and therapeutic targets in oncology has garnered immense research interest. This study aims to elucidate the relevance, biological roles, and mechanistic pathways of LncRNA HAGLR in the context of GC. The assessments of cell proliferation, migration, and invasion were executed using CCK-8, wound healing, and Transwell assays. The interactions between HAGLR, miR-20a-5p, and E2F1 were appraised through luciferase reporter assays, fluorescence in situ hybridization (FISH), and RNA immunoprecipitation (RIP). A tumor xenograft model provided in vivo validation for in vitro findings. Elevated levels of HAGLR in GC cells and tissue specimens were linked to worse patient outcomes. The inhibition of HAGLR led to a decrease in GC cell proliferation, migration, and invasion, whereas its activation prompted contrary effects. The impact of HAGLR on cell migration and invasion was notably associated with epithelial-mesenchymal transition (EMT). Through bioinformatics, luciferase reporter assays, FISH, RIP, and Western blot analyses, it was revealed that HAGLR acts as a molecular sponge for miR-20a-5p, consequently augmenting E2F1 levels. The data suggest that the HAGLR/miR-20a-5p/E2F1 regulatory cascade is implicated in GC pathogenesis, offering a novel therapeutic avenue for GC management.

MiR-106b-5p protects against drug-induced liver injury by targeting vimentin to stimulate liver regeneration.

Understanding the endogenous mechanism of adaptive response to drug-induced liver injury (arDILI) may discover innovative strategies to manage DILI. To gain mechanistic insight into arDILI, we investigated exosomal miRNAs in the adaptive response to toosendanin-induced liver injury (TILI) of mice. Exosomal miR-106b-5p was identified as a specific regulator of arDILI by comprehensive miRNA profiling. Outstandingly, miR-106b-5p agomir treatment alleviated TILI and other DILI by inhibiting apoptosis and promoting hepatocyte proliferation. Conversely, antagomir treatments had opposite effects, indicating that miR-106b-5p protects mice from liver injury. Injured hepatocytes released miR-106b-5p-enriched exosomes taken up by surrounding hepatocytes. Vim (encodes vimentin) was identified as an important target of miR-106b-5p by dual luciferase reporter and siRNA assays. Furthermore, single-cell RNA-sequencing analysis of toosendanin-injured mouse liver revealed a cluster of Vim + hepatocytes; nonetheless declined following miR-106b-5p cotreatment. More importantly, Vim knockout protected mice from acetaminophen poisoning and TILI. In the clinic, serum miR-106b-5p expression levels correlated with the severity of DILI. Indeed, liver biopsies of clinical cases exposed to different DILI causing drugs revealed marked vimentin expression among harmed hepatocytes, confirming clinical relevance. Together, we report mechanisms of arDILI whereby miR-106b-5p safeguards restorative tissue repair by targeting vimentin.

CLDN6 inhibits breast cancer growth and metastasis through SREBP1-mediated RAS palmitoylation

BackgroundBreast cancer (BC) ranks as the third most fatal malignant tumor worldwide, with a strong reliance on fatty acid metabolism. CLDN6, a candidate BC suppressor gene, was previously identified as a regulator of fatty acid biosynthesis; however, the underlying mechanism remains elusive. In this research, we aim to clarify the specific mechanism through which CLDN6 modulates fatty acid anabolism and its impact on BC growth and metastasis.MethodsCell function assays, tumor xenograft mouse models, and lung metastasis mouse models were conducted to evaluate BC growth and metastasis. Human palmitic acid assay, triglyceride assay, Nile red staining, and oil red O staining were employed to investigate fatty acid anabolism. Reverse transcription polymerase chain reaction (RT–PCR), western blot, immunohistochemistry (IHC) assay, nuclear fractionation, immunofluorescence (IF), immunoprecipitation and acyl–biotin exchange (IP-ABE), chromatin immunoprecipitation (ChIP), dual luciferase reporter assay, and co-immunoprecipitation (Co-IP) were applied to elucidate the underlying molecular mechanism. Moreover, tissue microarrays of BC were analyzed to explore the clinical implications.ResultsWe identified that CLDN6 inhibited BC growth and metastasis by impeding RAS palmitoylation both in vitro and in vivo. We proposed a unique theory suggesting that CLDN6 suppressed RAS palmitoylation through SREBP1-modulated de novo palmitic acid synthesis. Mechanistically, CLDN6 interacted with MAGI2 to prevent KLF5 from entering the nucleus, thereby restraining SREBF1 transcription. The downregulation of SREBP1 reduced de novo palmitic acid synthesis, hindering RAS palmitoylation and subsequent endosomal sorting complex required for transport (ESCRT)-mediated plasma membrane localization required for RAS oncogenic activation. Besides, targeting inhibition of RAS palmitoylation synergized with CLDN6 to repress BC progression.ConclusionsOur findings provide compelling evidence that CLDN6 suppresses the palmitic acid-induced RAS palmitoylation through the MAGI2/KLF5/SREBP1 axis, thereby impeding BC malignant progression. These results propose a new insight that monitoring CLDN6 expression alongside targeting inhibition of palmitic acid-mediated palmitoylation could be a viable strategy for treating oncogenic RAS-driven BC.Graphical

Hsa_circ_0020093 suppresses ovarian cancer progression by modulating LRPPRC activity and miR-107/LATS2 signaling

A substantive body of evidence has demonstrated the significant roles of circular RNA (circRNA) in cancer. However, the contribution of dysregulated circRNAs to ovarian cancer (OC) remains elusive. We aim to elucidate the critical roles and mechanisms of hsa_circ_0020093, which was demonstrated to be downregulated in OC tissues in our previous study. In this study, we confirmed the decreased expression of hsa_circ_0020093 in OC tissues and cell lines and demonstrated the negative correlation between its expression and FIGO stage, abdominal implantation and CA125 level of OC patients. Through gain and loss of function studies, we confirmed the inhibitory role of hsa_circ_0020093 in ovarian tumor growth in vitro and in vivo. Mechanistically, based on the peri-nuclear accumulation of hsa_circ_0020093, we discovered the interaction between hsa_circ_0020093 and the mitochondrial protein LRPPRC by RNA pull-down, mass spectrometry, RNA Binding Protein Immunoprecipitation. As a result, qRT-PCR and transmission electron microscopy results showed that the mitochondria mRNA expression and mitochondria abundance were decreased upon hsa_circ_0020093-overexpression. Meanwhile, we also unearthed the hsa_circ_0020093/miR-107/LATS2 axis in OC according to RNA-sequencing, RIP and luciferase reporter assay data. Furthermore, LRPPRC and LATS2 are both reported as the upstream regulators of YAP, our study also studied the crosstalk between hsa_circ_0020093, LRPPRC and miR-107/LATS2, and unearthed the up-regulation of phosphorylated YAP in hsa_circ_0020093-overexpressing OC cells and xenograft tumors. Collectively, our study indicated the novel mechanism of hsa_circ_0020093 in suppressing OC progression through both hsa_circ_0020093/LRPPRC and hsa_circ_0020093/miR-107/LATS2 axes, providing a potential therapeutic target for OC patients.