Knockdown of FOXK1 suppresses liver cancer cell viability by inhibiting glycolysis

"Friends or foes": a new perspective of tumour metabolic transcriptional modification

Energy metabolism plays a pivotal role in cancer clinical treatment and has become an important means of clinical diagnosis of tumour progression. However, current research mostly focuses on changes in metabolic products and neglects the deeper mechanisms of transcriptional regulation. This paper proposes a new perspective, establishing a comprehensive network that reveals the interaction between metabolism and transcription, which explores how tumour metabolism affects tumour progression through transcriptional modifications, and provides a novel approach for optimizing tumour treatment strategies. This viewpoint is conducive to overcoming current bottlenecks in treatment and promoting the development of drug combinations and personalized medicine.

Tanshinone I reprograms glycolysis metabolism to regulate histone H3 lysine 18 lactylation (H3K18la) and inhibits cancer cell growth in ovarian cancer

Salvia miltiorrhiza, the anticancer properties of these components are multifaceted, encompassing the inhibition of tumor growth, prevention of the metastatic spread of cancer cells, enhancement of the sensitivity of cancer cells to chemotherapy and radiation therapy, and the suppression of angiogenesis, which is crucial for tumor growth and survival. In the context of our recent study, we have discovered that tanshinone I, one of the active components of Salvia miltiorrhiza, possesses the ability to inhibit the proliferation of ovarian cancer cells, both in laboratory settings and within living organisms. To further understand the molecular mechanisms behind this effect, we conducted a comprehensive transcriptomic analysis. Our findings indicated that tanshinone I exerts its inhibitory action by downregulating the expression of genes associated with glycolysis. Specifically, tanshinone I decreased the expression of glycolysis-related genes such as HK2 (hexokinase 2), PFK (phosphofructokinase), ENO2 (enolase 2), and LDHA (lactate dehydrogenase A). Inhibiting lactate production by tanshinone I application reduced the level of histone H3 lysine 18 lactylation (H3K18la), which reduced the expression of tumor-associated genes, such as TTK, PDGFRβ, YTHDF2 and RUBCNL. In addition, tanshinone I alleviated the immunosuppressive tumor microenvironment. In summary, tanshinone I blocks glycolysis to regulate histone H3 lysine 18 lactylation (H3K18la), which inhibits ovarian cancer cell growth, revealing the anticancer mechanism of tanshinone I.

Experimental cell models of insulin resistance: overview and appraisal

Insulin resistance, a key factor in the development of type 2 diabetes mellitus (T2DM), is defined as a defect in insulin-mediated control of glucose metabolism in tissues such as liver, fat and muscle. Insulin resistance is a driving force behind various metabolic diseases, such as T2DM, hyperlipidemia, hypertension, coronary heart disease and fatty liver. Therefore, improving insulin sensitivity can be considered as an effective strategy for the prevention and treatment of these complex metabolic diseases. Cell-based models are extensively employed for the study of pathological mechanisms and drug screening, particularly in relation to insulin resistance in T2DM. Currently, numerous methods are available for the establishment of in vitro insulin resistance models, a comprehensive review of these models is required and can serve as an excellent introduction or understanding for researchers undertaking studies in this filed. This review examines and discusses the primary methods for establishing and evaluating insulin resistance cell models. Furthermore, it highlights key issues and suggestions on cell selection, establishment, evaluation and drug screening of insulin resistance, thereby providing valuable references for the future research efforts.

Exploring the impact of circRNAs on cancer glycolysis: Insights into tumor progression and therapeutic strategies

Cancer cells exhibit altered metabolic pathways, prominently featuring enhanced glycolytic activity to sustain their rapid growth and proliferation. Dysregulation of glycolysis is a well-established hallmark of cancer and contributes to tumor progression and resistance to therapy. Increased glycolysis supplies the energy necessary for increased proliferation and creates an acidic milieu, which in turn encourages tumor cells' infiltration, metastasis, and chemoresistance. Circular RNAs (circRNAs) have emerged as pivotal players in diverse biological processes, including cancer development and metabolic reprogramming. The interplay between circRNAs and glycolysis is explored, illuminating how circRNAs regulate key glycolysis-associated genes and enzymes, thereby influencing tumor metabolic profiles. In this overview, we highlight the mechanisms by which circRNAs regulate glycolytic enzymes and modulate glycolysis. In addition, we discuss the clinical implications of dysregulated circRNAs in cancer glycolysis, including their potential use as diagnostic and prognostic biomarkers. All in all, in this overview, we provide the most recent findings on how circRNAs operate at the molecular level to control glycolysis in various types of cancer, including hepatocellular carcinoma (HCC), prostate cancer (PCa), colorectal cancer (CRC), cervical cancer (CC), glioma, non-small cell lung cancer (NSCLC), breast cancer, and gastric cancer (GC). In conclusion, this review provides a comprehensive overview of the significance of circRNAs in cancer glycolysis, shedding light on their intricate roles in tumor development and presenting innovative therapeutic avenues.

circ-ATAD1 as Competing Endogenous RNA for miR-191-5p Forces Non-small Cell Lung Cancer Progression

The association of circular RNAs (circRNAs) with non-small cell lung cancer (NSCLC) has been recognized extensively. In view of this, our study particularly surveyed the underlying mechanism of circ-ATAD1 in the disease. First, an analysis of the clinical expression of circ-ATPase family AAA domain containing 1 (ATAD1) was performed, followed by further evaluation of the relationship between circ-ATAD1 expression and prognosis. Then, A549 cells were treated with single transfection or combined transfection with the plasmid vectors that interfere with circ-ATAD1 or miR-191-5p. circ-ATAD1 and miR-191-5p levels were detected by reverse transcription quantitative polymerase chain reaction to verify the transfection success. Then, cell proliferation was checked by cell count kit-8 and clonal formation test. Cell apoptosis was analyzed by flow cytometry. Cell migration and invasion were examined by wound healing assay and Transwell. Finally, the targeting of miR-191-5p to circ-ATAD1 or Forkhead Box K1 (FOXK1) was verified by bioinformation website starBase analysis and dual-luciferase reporter assay. circ-ATAD1 was expressed abundantly in tumor tissues of NSCLC patients and had a predictive value in poor prognosis. circ-ATAD1 underexpression or miR-191-5p overexpression could obstruct A549 cells to behave aggressively, while circ-ATAD1 upregulation or miR-191-5p depletion resulted in the promotion of aggressiveness of A549 cells. Interestingly, circ-ATAD1 could decoy miR-191-5p. miR-191-5p negatively regulated FOXK1 expression, and downregulating miR-191-5p or upregulating FOXK1 rescued circ-ATAD1 downregulation-mediated influences on NSCLC cells. circ-ATAD1 accelerates NSCLC progression by absorbing miR-191-5p to upregulate FOXK1 expression.

Genome-wide association study of osteoporosis identifies genetic risk and interactions with Dietary Approaches to Stop Hypertension diet and sugar-sweetened beverages in a Hispanic cohort of older adults

Osteoporosis (OP) and low bone mass can be debilitating and costly conditions if not acted on quickly. This disease is also difficult to diagnose as the symptoms develop unnoticed until fracture occurs. Therefore, gaining understanding of the genetic risk associated with these conditions could be beneficial for health-care professionals in early detection and prevention. The Boston Puerto Rican Osteoporosis (BPROS) study, an ancillary study to the Boston Puerto Rican Health Study (BPRHS), collected information regarding bone and bone health. All bone measurements were taken during regular BPROS visits using dual-energy X-ray absorptiometry. The OP was defined as T-score ≤ -2.5 (≥2.5 SDs below peak bone mass). Dietary variables were collected at the second wave of the BPRHS via a food frequency questionnaire. We conducted genome-wide associations with bone outcomes, including BMD and OP for 978 participants. We also examined the interactions with dietary quality on the relationships between genotype and bone outcomes. We further tested if candidate genetic variants described in previous GWAS on OP and BMD contribute to OP risk in this population. Four variants were associated with OP: rs114829316 (IQ motif containing J gene), rs76603051, rs12214684 (melanin-concentrating hormone receptor 2 gene), and rs77303493 (Ras and Rab interactor 2 gene), and 2 variants were associated with BMD of lumbar spine (rs11855618, cingulin-like 1 gene) and hip (rs73480593, NTRK2), reaching the genome-wide significance threshold of P ≤ 5E-08. In a gene-diet interaction analysis, we found that 1 SNP showed a significant interaction with the overall Dietary Approaches to Stop Hypertension (DASH) score, and 7 SNPs with sugar-sweetened beverages (SSBs), a major contributor to the DASH score. This study identifies new genetic markers related to OP and BMD in older Hispanic adults. Additionally, we uncovered unique genetic markers that interact with dietary quality, specifically SSBs, in relation to bone health. These findings may be useful to guide early detection and preventative care.

PI3K signaling-regulated metabolic reprogramming: From mechanism to application

Oncogenic signaling involved in tumor metabolic reprogramming. Tumorigenesis was not only determined by the mutations or deletion of oncogenes but also accompanied by the reprogramming of cellular metabolism. Metabolic alterations play a crucial regulatory role in the development and progression of tumors. Oncogenic PI3K/AKT signaling mediates the metabolic switch in cancer cells and immune cells in the tumor microenvironment. PI3K/AKT and its downstream effector branch off and connect to multiple steps of metabolism, such as glucose, lipids, and amino acids. Thus, PI3K inhibitor could effectively regulate metabolic pathway and impede the oncogenic process and some key metabolic proteins or critical enzymes also constitute biomarkers for tumor diagnosis and treatment. In the current review, we summarize the significant effect of PI3K/AKT signaling toward tumor metabolism, it enables us to obtain the better understanding for this interaction and develop more effective therapeutic strategies targeting cancer cell metabolism.

miR-144-3p represses hepatocellular carcinoma progression by affecting cell aerobic glycolysis via FOXK1

Aerobic glycolysis is a unique mark of cancer cells, which enables therapeutic intervention in cancer. Forkhead box K1 (FOXK1) is a transcription factor that facilitates the progression of multiple cancers including hepatocellular carcinoma (HCC). Nevertheless, it is unclear whether or not FOXK1 can affect HCC cell glycolysis. This study attempted to study the effect of FOXK1 on HCC cell glycolysis. Expression of mature miRNAs and mRNAs, as well as clinical data, was downloaded from The Cancer Genome Atlas-Liver hepatocellular carcinoma (TCGA-LIHC) dataset. FOXK1 and miR-144-3p levels were assessed through quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Targeting of the relationship between miR-144-3p and FOXK1 was verified via a dual-luciferase assay. Pathway enrichment analysis of FOXK1 was performed by Gene Set Enrichment Analysis (GSEA). Cell function assays revealed the glycolytic ability, cell viability, migration, invasion, cell cycle, and apoptosis of HCC cells in each treatment group. Bioinformatics analysis suggested that FOXK1 was upregulated in tissues of HCC patients, while the upstream miR-144-3p was downregulated in tumour tissues. Dual-luciferase assay implied a targeting relationship between miR-144-3p and FOXK1. Cellular experiments implied that silencing FOXK1 repressed HCC cell glycolysis, which in turn inhibited the HCC malignant progression. Rescue assay confirmed that miR-144-3p repressed glycolysis in HCC cells by targeting FOXK1, and then repressed HCC malignant progression. miR-144-3p/FOXK1 axis repressed malignant progression of HCC via affecting the aerobic glycolytic process of HCC cells. miR-144-3p and FOXK1 have the potential to become new therapeutic targets for HCC, which provide new insights for HCC treatment.

FOXK1 promotes nonalcoholic fatty liver disease by mediating mTORC1-dependent inhibition of hepatic fatty acid oxidation

Nonalcoholic fatty liver disease (NAFLD) is a chronic metabolic disorder caused by overnutrition and can lead to nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). The transcription factor Forkhead box K1 (FOXK1) is implicated in regulation of lipid metabolism downstream of mechanistic target of rapamycin complex 1 (mTORC1), but its role in NAFLD-NASH pathogenesis is understudied. Here, we show that FOXK1 mediates nutrient-dependent suppression of lipid catabolism in the liver. Hepatocyte-specific deletion of Foxk1 in mice fed a NASH-inducing diet ameliorates not only hepatic steatosis but also associated inflammation, fibrosis, and tumorigenesis, resulting in improved survival. Genome-wide transcriptomic and chromatin immunoprecipitation analyses identify several lipid metabolism-related genes, including Ppara, as direct targets of FOXK1 in the liver. Our results suggest that FOXK1 plays a key role in the regulation of hepatic lipid metabolism and that its inhibition is a promising therapeutic strategy for NAFLD-NASH, as well as for HCC.

FOXK2 affects cancer cell response to chemotherapy by promoting nucleotide de novo synthesis

AIMS

Nucleotide de novo synthesis is essential to cell growth and survival, and its dysregulation leads to cancers and drug resistance. However, how this pathway is dysregulated in cancer has not been well clarified. This study aimed to identify the regulatory mechanisms of nucleotide de novo synthesis and drug resistance.

METHODS

By combining the ChIP-Seq data from the Cistrome Data Browser, RNA sequencing (RNA-Seq) and a luciferase-based promoter assay, we identified transcription factor FOXK2 as a regulator of nucleotide de novo synthesis. To explore the biological functions and mechanisms of FOXK2 in cancers, we conducted biochemical and cell biology assays in vitro and in vivo. Finally, we assessed the clinical significance of FOXK2 in hepatocellular carcinoma.

RESULTS

FOXK2 directly regulates the expression of nucleotide synthetic genes, promoting tumor growth and cancer cell resistance to chemotherapy. FOXK2 is SUMOylated by PIAS4, which elicits FOXK2 nuclear translocation, binding to the promoter regions and transcription of nucleotide synthetic genes. FOXK2 SUMOylation is repressed by DNA damage, and elevated FOXK2 SUMOylation promotes nucleotide de novo synthesis which causes resistance to 5-FU in hepatocellular carcinoma. Clinically, elevated expression of FOXK2 in hepatocellular carcinoma patients was associated with increased nucleotide synthetic gene expression and correlated with poor prognoses for patients.

CONCLUSION

Our findings establish FOXK2 as a novel regulator of nucleotide de novo synthesis, with potentially important implications for cancer etiology and drug resistance.

Multifaceted roles of aerobic glycolysis and oxidative phosphorylation in hepatocellular carcinoma

Liver cancer is a common malignancy with high morbidity and mortality rates. Changes in liver metabolism are key factors in the development of primary hepatic carcinoma, and mitochondrial dysfunction is closely related to the occurrence and development of tumours. Accordingly, the study of the metabolic mechanism of mitochondria in primary hepatic carcinomas has gained increasing attention. A growing body of research suggests that defects in mitochondrial respiration are not generally responsible for aerobic glycolysis, nor are they typically selected during tumour evolution. Conversely, the dysfunction of mitochondrial oxidative phosphorylation (OXPHOS) may promote the proliferation, metastasis, and invasion of primary hepatic carcinoma. This review presents the current paradigm of the roles of aerobic glycolysis and OXPHOS in the occurrence and development of hepatocellular carcinoma (HCC). Mitochondrial OXPHOS and cytoplasmic glycolysis cooperate to maintain the energy balance in HCC cells. Our study provides evidence for the targeting of mitochondrial metabolism as a potential therapy for HCC.

The Role of PI3K/AKT/mTOR Signaling in Hepatocellular Carcinoma Metabolism

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths in the world. Metabolic reprogramming is considered a new hallmark of cancer, but it remains unclearly described in HCC. The dysregulation of the PI3K/AKT/mTOR signaling pathway is common in HCC and is, therefore, a topic of further research and the concern of developing a novel target for liver cancer therapy. In this review, we illustrate mechanisms by which this signaling network is accountable for regulating HCC cellular metabolism, including glucose metabolism, lipid metabolism, amino acid metabolism, pyrimidine metabolism, and oxidative metabolism, and summarize the ongoing clinical trials based on the inhibition of the PI3K/AKT/mTOR pathway in HCC.

The Function of FoxK Transcription Factors in Diseases

Forkhead box (FOX) transcription factors play a crucial role in the regulation of many diseases, being an evolutionarily conserved superfamily of transcription factors. In recent years, FoxK1/2, members of its family, has been the subject of research. Even though FoxK1 and FoxK2 have some functional overlap, increasing evidence indicates that the regulatory functions of FoxK1 and FoxK2 are not the same in various physiological and disease states. It is important to understand the biological function and mechanism of FoxK1/2 for better understanding pathogenesis of diseases, predicting prognosis, and finding new therapeutic targets. There is, however, a lack of comprehensive and systematic analysis of the similarities and differences of FoxK1/2 roles in disease, prompting us to perform a literature review.

Circular RNA circ_0006948 Promotes Esophageal Squamous Cell Carcinoma Progression by Regulating microRNA-3612/LASP1 Axis

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is the most prevalent malignancy worldwide. Circular RNAs (circRNAs) circ_0006948 is reported to be upregulated in ESCC cells.

AIMS

This study is designed to explore the role and mechanism of circ_0006948 in ESCC progression.

METHODS

Circ_0006948, linear FNDC3B, microRNA-3612 (miR-3612), and LIM and SH3 protein 1 (LASP1) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, colony number, migration, invasion, and apoptosis were examined by Cell Counting Kit-8 (CCK-8), colony formation, transwell, and flow cytometry assays, severally. Glucose consumption, lactate production, and ATP level were measured by the corresponding kits. Protein levels of hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA), and LASP1 were assessed by western blot assay. The cytoplasmic localization of circ_0006948 was identified by the subcellular fractionation assay. The binding relationship between miR-3612 and circ_0006948 or LASP1 was predicted by starBase or TargetScan and then verified by a dual-luciferase reporter assay. The biological role of circ_0006948 on ESCC tumor growth was examined by the xenograft tumor model in vivo.

RESULTS

Circ_0006948 and LASP1 were increased, and miR-3612 was decreased in ESCC tissues and cells. Furthermore, circ_0006948 knockdown could suppress cell viability, colony number, migration, invasion, glycolysis, and boost apoptosis in ESCC cells. Mechanically, circ_0006948 could act as a sponge of miR-3612 to regulate LASP1 expression. In addition, circ_0006948 silencing inhibited ESCC tumor growth in vivo.

CONCLUSION

Circ_0006948 boosted ESCC progression partly by regulating the miR-3612/LASP1 axis, providing an underlying therapeutic target for the ESCC treatment.

Current status of cancer starvation therapy

Conventional therapies for malignant tumors have limitations and disadvantages. In recent years, the cancer starvation therapy has emerged which intends to deprive cancer cells of nutritional supply. There are several approaches to"starve" cancer cells: to intervene tumor angiogenesis by targeted inhibition of angiogenic factors or their receptors and integrins; to block the blood supply of cancer cells by embolizing or compressing blood vessels; to intervene metabolic process of cancer cells by inhibition of the signal pathways of mitochondrial serine-glycine-one earbon metabolism, glycolysis and amino acid metabolism; cancer starvation therapy can be employed with oxidation therapy, chemotherapy, sonodynamic therapy, anti-autophagy therapy or other therapies to achieve synergistic effects. This article reviews the research progress of cancer starvation therapy in recent years and discusses the existing problems.

Circular RNA Eps15-homology domain containing protein 2 motivates proliferation, glycolysis but refrains autophagy in non-small cell lung cancer via crosstalk with microRNA-3186-3p and forkhead box K1

Numerous studies have clarified the involvement of circular RNAs (circRNAs) in modulating malignant behavior of non-small cell lung cancer (NSCLC), while the concrete mechanism is not completely elucidated. The aim of the study was to figure out the latent functions and molecular mechanisms of circRNA Eps15-homology domain containing protein 2 (EHD2) on NSCLC proliferation, glycolysis and autophagy. The results clarified in NSCLC elevated expression of circEHD2 and declined expression of microRNA (miR)-3186-3p. Repressive circEHD2 or enhancive miR-3186-3p facilitated cell apoptosis rate and autophagy substrates LC3BII and Beclin-1, but curbed the colony-formation and DNA replication ability of NSCLC, glucose consumption, lactic acid production, glycolytic rate-limiting enzyme HK-2 and glutamine hydrolase GLS1 and P62, while overexpressed circEHD2 was adverse. Meanwhile, the impacts of repressive and elevated circEHD2 on NSCLC were turned around via reduced miR-3186-3p or forkhead box k1 (FOXK1) separately. Mechanically, FOXK1 was augmented via circEHD2's competitive integration of miR-3186-3p. Depressive circEHD2 refrained NSCLC tumor growth, which was accelerated via enhancive one. All in all, circEHD2 accelerates the proliferation and glycolysis of NSCLC, but refrains autophagy and apoptosis via strengthening FOXK1 via the adsorption of miR-3186-3p, which is supposed to be a latent molecular target for NSCLC therapy later.

circ-PRKCI targets miR-1294 and miR-186-5p by downregulating FOXK1 expression to suppress glycolysis in hepatocellular carcinoma

Numerous human circular RNAs (circRNAs/circ) have been functionally characterized. However, the potential role of circ-protein kinase C iota (PRKCI) in hepatocellular carcinoma (HCC) remains unknown. The effects of each transfection and expression levels of circ-PRKCI, microRNA (miR)-1294, miR-186-5p and forkhead box K1 (FOXK1) in HCC cells were analyzed using reverse transcription-quantitative PCR analysis. The interactions between circ-PRKCI and miR-1294 or miR-186-5p, and miR-1294 or miR-186-5p and FOXK1 were validated using dual luciferase reporter assays. The viability, invasion and migration of HCC cells were determined using Cell Counting Kit-8, Transwell and wound healing assays, respectively. The expression levels of FOXK1, hexokinase-2 (HK2), glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA) in HCC cells were analyzed using western blotting. The levels of glucose and lactic acid in the cultured supernatant were detected using commercially available kits. The results of the present study revealed that miR-1294 and miR-186-5p expression levels were downregulated in the HCC cell line, HCCLM3, and were subsequently downregulated by circ-PRKCI overexpression and upregulated by the knockdown of circ-PRKCI. circ-PRKCI overexpression promoted the viability, invasion and migration of HCCLM3 cells, which was also reversed by the overexpression of miR-1294 and miR-186-5p. In addition, the overexpression of circ-PRKCI upregulated FOXK1 expression levels, while the overexpression of miR-1294 and miR-186-5p downregulated FOXK1 expression levels. Conversely, the knockdown of circ-PRKCI expression downregulated FOXK1 expression levels, while the knockdown of miR-1294 and miR-186-5p upregulated FOXK1 expression levels. Furthermore, circ-PRKCI was identified to target miR-1294 and miR-186-5p, and miR-1294 and miR-186-5p were subsequently found to target FOXK1. The overexpression of circ-PRKCI also increased glucose and lactic acid levels, while the knockdown of FOXK1 decreased glucose and lactic acid levels. The knockdown of circ-PRKCI decreased glucose and lactic acid levels, which were reversed by FOXK1 overexpression. In conclusion, the findings of the present study suggested that circ-PRKCI may promote the viability, invasion and migration of HCC cells by sponging miR-1294 and miR-186-5p to upregulate FOXK1 expression levels.

Hypoxia-induced CNPY2 upregulation promotes glycolysis in cervical cancer through activation of AKT pathway

This study aimed to investigate the function and mechanism of the protein-coding gene CNPY2 in the glycolysis of cervical cancer cells. Cells were exposed to normoxia and hypoxia conditions. Knockdown and ectopic overexpression of CNPY2 were achieved by transfection of small interfering RNA (siRNA) specific to CNPY2 or CNPY2 overexpression vectors, respectively. Quantitative real-time PCR and Western blot were used to evaluate CNPY2 expression in patient specimens and different cervical cancer cell lines under normoxia or hypoxia conditions. Cell viability was assessed by MTT and colony formation assays. Glucose consumption, lactate production, oxygen consumption and ATP production were analyzed by enzyme-linked immunosorbent assays. Dual-luciferase reporter assay and chromatin immunoprecipitation assay were performed to detect interaction between hypoxia-induced factor 1α (HIF-1α) on CNPY2 promoter. CNPY2 upregulation was a characteristic of cervical cancer and correlated with poor prognosis. Knockdown and overexpression of CNPY2 inhibited and promoted proliferation glucose consumption, lactate production, oxygen consumption and ATP production in cervical cancer cells, respectively. CNPY2 was transcriptionally regulated by HIF-1α. The hypoxia-induced "Warburg effect" in cervical cancer cells was at least partially dependent on the CNPY2/AKT signaling pathway. Hypoxia-induced CNPY2 promoted glycolysis in cervical cancer cells by activating the AKT pathway. CNPY2 may serve as a potential diagnostic marker and therapeutic target for cervical cancer patients.

SNHG1 knockdown upregulates miR-376a and downregulates FOXK1/Snail axis to prevent tumor growth and metastasis in HCC

Long non-coding RNAs (lncRNAs), microRNAs (miRNAs or miRs), and genes are emerging players in cancer progression. In the present study, we explored the roles and interactions of oncogenic lncRNA small nucleolar RNA host gene 1 (SNHG1), miR-376, forkhead box protein K1 (FOXK1), and Snail in hepatocellular carcinoma (HCC). Expression of SNHG1, miR-376, and FOXK1 in HCC was characterized in clinical HCC tissues of 75 patients with HCC. The interactions between SNHG1 and miR-376 and between miR-376 and FOXK1 were predicted and confirmed by dual-luciferase reporter gene and RNA immunoprecipitation assays. Overexpression and knockdown experiments were performed in HCC cells to examine the effects of the SNHG1/miR-376/FOXK1/Snail axis on viability, apoptosis, invasiveness, and migrating abilities. Their effects on tumor growth and metastasis were validated in nude mouse models. SNHG1 and FOXK1 were upregulated, and miR-376a was downregulated in HCC. SNHG1 knockdown contributed to suppression of HCC cell viability, invasion, and migration properties and promotion of apoptosis. SNHG1 could competitively bind to miR-376a to upregulate its target gene FOXK1, which upregulated Snail. SNHG1 knockdown delayed cancer progression both in vitro and in vivo by upregulating miR-376a and downregulating FOXK1 and Snail. SNHG1 knockdown exerts anti-tumor activity in HCC, suggesting a therapeutic target.

Prognostic and Predictive Value of a 15 Transcription Factors (TFs) Panel for Hepatocellular Carcinoma

Purpose

Hepatocellular carcinoma (HCC) is one of the most devastating diseases worldwide. Limited performance of clinicopathologic parameters as prognostic factors underscores more accurate and effective biomarkers for high-confidence prognosis that guide decision-making for optimal treatment of HCC. The aim of the present study was to establish a novel panel to improve prognosis prediction of HCC patients, with a particular interest in transcription factors (TFs).

Materials and Methods

A TF-related prognosis model of liver cancer with data from ICGC-LIRP-JI cohort successively were processed by univariate and multivariate Cox regression analysis. Then, for evaluating the prognostic prediction value of the model, receiver operating characteristic (ROC) curve and survival analysis were performed both with internal data from the International Cancer Genome Consortium (ICGC) and external data from The Cancer Genome Atlas (TCGA). Furthermore, we verified the expression of three genes in HCC cell lines by Western blot and qPCR and protein expression level by IHC in liver cancer patients’ sample. Finally, we constructed a TF clinical characteristics nomogram to furtherly predict liver cancer patient survival probability with TCGA cohort.

Results

By Cox regression analysis, a panel of 15 TFs (ZNF331, MYCN, AHRR, LEF1, ZNF780A, POU1F1, DLX5, ZNF775, PLSCR1, FOXK1, TAL2, ZNF558, SOX9, TCFL5, GSC) was identified to present with powerful predictive performance for overall survival of HCC patients based on internal ICGC cohort and external TCGA cohort. A nomogram that integrates these factors was established, allowing efficient prediction of survival probabilities and displaying higher clinical utility.

Conclusion

The 15-TF panel is an independent prognostic factor for HCC, and 15 TF-based nomogram might provide implication an effective approach for HCC patient management and treatment.

LINC00460 Enhances Bladder Carcinoma Cell Proliferation and Migration by Modulating miR-612/FOXK1 Axis

INTRODUCTION

LincRNA (long intergenic noncoding RNA) has been indicated as a mediator in tumorigenesis of bladder carcinoma. This study was performed to evaluate the role of LINC00460 in bladder carcinoma progression.

METHODS

Expression levels of LINC00460 in bladder carcinoma tissues and cell lines were analyzed via qRT-PCR. MTT, EdU (5-ethynyl-2'-deoxyuridine) staining, and colony formation assays were utilized to evaluate cell viability and proliferation. The wound healing assay was performed to evaluate bladder cancer cell migration, and the transwell assay was used to evaluate cell invasion. The microRNA (miRNA) target of LINC00460 and the corresponding target gene were validated via the dual luciferase activity assay. The tumorigenic function of LINC00460 was determined via establishment of a xenotransplanted tumor model.

RESULTS

LINC00460 was elevated in bladder carcinoma tissues and cell lines. Elevated LINC00460 was associated with shorter overall survival of bladder carcinoma patients. Overexpression of LINC00460 promoted cell viability, proliferation, invasion, and migration, while silencing of LINC00460 indicated the opposite effect on bladder carcinoma progression. LINC00460 could directly bind to miR-612 and inhibit miR-612 expression. Moreover, LINC00460 expression was negatively correlated with miR-612 in patients with bladder carcinoma. FOXK1 (Forkhead Box K1) was identified as the target of miR-612 and upregulated in patients with bladder carcinoma. Overexpression of FOXK1 attenuated interference of LINC00460-inhibited bladder carcinoma progression. Knockdown of LINC00460 suppressed in vivo bladder carcinoma growth.

CONCLUSIONS

LINC00460 promoted bladder carcinoma progression via sponging miR-612 to facilitate FOXK1 expression, suggesting that LINC00460 might have the potential of being explored as a therapeutic target for treatment of bladder carcinoma.

A glycolysis-related gene pairs signature predicts prognosis in patients with hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the most universal malignant liver tumors worldwide. However, there were no systematic studies to establish glycolysis‑related gene pairs (GRGPs) signatures for the patients with HCC. Therefore, the study aimed to establish novel GRGPs signatures to better predict the prognosis of HCC.

METHODS

Based on the data from Gene Expression Omnibus, The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium databases, glycolysis-related mRNAs were used to construct GRGPs. Cox regression was applied to establish a seventeen GRGPs signature in TCGA dataset, which was verified in two validation (European and American, and Asian) datasets.

RESULTS

Seventeen prognostic GRGPs (HMMR_PFKFB1, CHST1_GYS2, MERTK_GYS2, GPC1_GYS2, LDHA_GOT2, IDUA_GNPDA1, IDUA_ME2, IDUA_G6PD, IDUA_GPC1, MPI_GPC1, SDC2_LDHA, PRPS1_PLOD2, GALK1_IER3, MET_PLOD2, GUSB_IGFBP3, IL13RA1_IGFBP3 and CYB5A_IGFBP3) were identified to be significantly progressive factors for the patients with HCC in the TCGA dataset, which constituted a GRGPs signature. The patients with HCC were classified into low-risk group and high-risk group based on the GRGPs signature. The GRGPs signature was a significantly independent prognostic indicator for the patients with HCC in TCGA (log-rank P = 2.898e-14). Consistent with the TCGA dataset, the patients in low-risk group had a longer OS in two validation datasets (European and American: P = 1.143e-02, and Asian: P = 6.342e-08). Additionally, the GRGPs signature was also validated as a significantly independent prognostic indicator in two validation datasets.

CONCLUSION

The seventeen GRGPs and their signature might be molecular biomarkers and therapeutic targets for the patients with HCC.

LncRNA TMPO-AS1 promotes hepatocellular carcinoma cell proliferation, migration and invasion through sponging miR-329-3p to stimulate FOXK1-mediated AKT/mTOR signaling pathway

Purpose

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer‐related death worldwide. Numerous analyses have revealed the abnormal expression of long non‐coding RNAs (lncRNAs) in HCC cells. This study aims to explore biological functions of lncRNA TMPO‐AS1 (TMPO antisense RNA 1) in HCC cell proliferation, apoptosis, invasion and migration.

Methods

The gene expression in HCC tissues and cell lines were measured by qRT‐PCR. The role of TMPO‐AS1 in HCC was confirmed by CCK‐8, colony formation, TUNEL, transwell and western blot as well as by in vivo experiments. RNA pull down and luciferase reporter assays were utilized to prove the binding relationship between TMPO‐AS1/FOXK1 (forkhead box K1) andmiR‐329‐3p. Rescue assays elucidated the regulatory effects of TMPO‐AS1/miR‐329‐3p/FOXK1/AKT/mTOR pathway on cellular activities in HCC.

Results

TMPO‐AS1was upregulated in HCC tissues and cells and its depletion inhibits HCC cell proliferation, invasion, migration, and EMT process as well as tumor growth. Furthermore, TMPO‐AS1 could bind with miR‐329‐3p, which suppressed HCC cell proliferation. FOXK1 served as the target gene of miR‐329‐3p and TMPO‐AS1 upregulated FOXK1 by sponging miR‐329‐3p in HCC cells. Additionally, FOXK1 overexpression or miR‐329‐3p inhibitor neutralized the repressing effects of TMPO‐AS1 knockdown on HCC development. Finally, it verified that TMPO‐AS1 could regulate AKT/mTOR pathway via FOXK1 to promote HCC.

Conclusion

TMPO‐AS1 contributes to HCC progression by sponging miR‐329‐3p to activate FOXK1‐mediated AKT/mTOR signaling pathway.

FOXK1 Promotes Proliferation and Metastasis of Gallbladder Cancer by Activating AKT/mTOR Signaling Pathway

Gallbladder cancer (GBC) is one of the most lethal malignancies worldwide, with extremely poor prognosis. Recently, forkhead box k1 (FOXK1), a member of the FOX transcription factor family, has been reported to be correlated with tumor progression in multiple malignancies. However, the role of FOXK1 in GBC has not been elucidated. In this study, we demonstrated that the expression level of FOXK1 was elevated in human GBC tissues and associated with increased liver metastasis, poor histological differentiation, advanced TNM stage, and shorter overall survival. Knockdown of FOXK1 expression inhibited GBC cells proliferation and metastasis. Consistently, overexpression of FOXK1 promoted GBC cells progression. Mechanical investigations verified that knockdown of FOXK1 could lead to G1/S cell cycle arrest through downregulating CDK4, CDK6, cyclin D1, and cyclin E1. And FOXK1 could regulate the expression of epithelial–mesenchymal transition (EMT) related proteins E-cad, N-cad, and Vimentin. Moreover, we found that FOXK1 could regulate the activation of Akt/mTOR signaling pathway. In addition, AKT special inhibitor MK-2206 could abolish the proliferation and metastasis discrepancy between FOXK1 overexpression GBC cells and control cells, which suggested the tumorpromoting effect of FOXK1 may be partially related with the activations of Akt/mTOR signaling pathway. Collectively, our results suggested that FOXK1 promotes GBC cells progression and represent a novel prognostic biomarker and potential therapeutic target in GBC.

Forkhead box K1 regulates the malignant behavior of gastric cancer by inhibiting autophagy

Background

Forkhead box K1 (FOXK1) is a transcription factor that contributes to cancer development, but it is unclear how FOXK1 regulates the proliferation and migration of gastric cancer (GC) cells. The purpose of this study was to investigate the clinical significance, biological function, and molecular mechanisms of FOXK1 in GC.

Methods

We conducted bioinformatics assays and western blotting to assess FOXK1 expression. Then, we performed immunohistochemistry (IHC) with tissue microarrays (TMAs) to assess FOXK1 expression in order to identify an association between FOXK1 expression levels and clinical parameters. We used 5-ethynyl-2'-deoxyuridine (EdU), wound healing and Transwell assays to determine whether FOXK1 promotes malignant behaviors in GC. Furthermore, immunofluorescence staining, transmission electron microscopy and western blotting were used to verify an association between FOXK1 and autophagy.

Results

We observed high levels of FOXK1 expression in GC tissues, which were associated with the degree of malignancy in GC. FOXK1 promotes the malignant behavior of GC by regulating autophagy via activation of the class I phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway and inhibition of the expression of class III PI3K.

Conclusions

These findings provide a new target for the comprehensive treatment of GC by highlighting the relationship between FOXK1 and malignant behaviors in GC.

Long non-coding RNA MCM3AP-AS1 promotes growth and migration through modulating FOXK1 by sponging miR-138-5p in pancreatic cancer

Background

Pancreatic cancer (PC) is a type of malignant gastrointestinal tumor. Long non-coding RNA MCM3AP antisense RNA 1 (MCM3AP-AS1) has been reported to stimulate proliferation, migration and invasion in several types of tumors. However, the role of MCM3AP-AS1 in PC remains unclear.

Methods

MCM3AP-AS1, microRNA miR-138-5p (miR-138-5p) and FOXK1 levels were detected using quantitative real time PCR. Cell proliferation, migration and invasion were analyzed. Dual luciferase reporter assay was used to confirm the relationship between MCM3AP-AS1 and miR-138-5p, between miR-138-5p and FOXK1. Protein levels were identified using western blot analysis.

Results

MCM3AP-AS1 overexpression promoted proliferation, migration and invasion in PC cells. MCM3AP-AS1 silencing showed a suppressive effect on cell growth in PC cells. Moreover, MCM3AP-AS1 knockdown suppressed tumor growth in mice. Dual luciferase reporter assay demonstrated MCM3AP-AS1 could sponge microRNA-138-5p (miR-138-5p), and FOXK1 could bind with miR-138-5p. Positive correlation between MCM3AP-AS1 and FOXK1 was testified, as well as negative correlation between miR-138-5p and FOXK1. MCM3AP-AS1 promoted FOXK1 expression by targeting miR-138-5p, and MCM3AP-AS1 facilitated growth and invasion in PC cells by FOXK1.

Conclusion

MCM3AP-AS1 promoted growth and migration through modulating miR-138-5p/FOXK1 axis in PC, providing insights into MCM3AP-AS1/miR-138-5p/FOXK1 axis as novel candidates for PC therapy from bench to clinic.

PLOD2 promotes aerobic glycolysis and cell progression in colorectal cancer by upregulating HK2

The purpose of this study was to characterize the expression of procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2), a membrane-bound homodimeric enzyme that specifically hydroxylates lysine in the telopeptide of procollagens, and assess the clinical significance of PLOD2 in colorectal cancer (CRC). Our results show that PLOD2 is highly expressed in CRC tumor tissues and cell lines, both at the mRNA and protein levels. Next, we found that PLOD2 was positively correlated with tumor grade (P = 0.001), T stage (P = 0.001), N stage (P < 0.001), and an advanced TNM stage (P < 0.001). Knockdown of PLOD2 attenuated CRC cell proliferation, migration, and invasiveness, in vitro. Our analysis of the mechanism behind the effects of PLOD2 suggests that PLOD2 affected glycolysis by regulating the expression of hexokinase 2 (HK2). HK2 reverses the inhibitory effects of PLOD2 knockdown in CRC. Furthermore, the data suggest that PLOD2 regulates the expression of HK2 via the STAT3 signaling pathway. Survival analysis revealed that high expression levels of PLOD2 (HR = 3.800, P < 0.001) and HK2 expression (HR = 10.222, P < 0.001) correlated with the overall survival rate. After analyzing their expression and correlation, PLOD2 positively correlated with HK2 (r = 0.590, P < 0.001). Our findings have revealed that PLOD2 is a novel regulatory factor in glucose metabolism, exerted via controlling HK2 expression in CRC cells, suggesting PLOD2 as a promising therapeutic target for CRC treatment.

MicroRNA-652 suppresses malignant phenotypes in glioblastoma multiforme via FOXK1-mediated AKT/mTOR signaling pathway

Purpose

An increasing number of studies have documented that dysregulation of microRNAs (miRNAs) is common in glioblastoma multiforme (GBM). miR-652 is aberrantly expressed in various human cancers and plays important roles in numerous cancer-related processes. However, the expression profiles and potential roles of miR-652 in GBM remain largely unknown.

Patients and methods

Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to determine miR-652 expression in GBM tissues and cell lines. The effects of miR-652 upregulation on GBM cell proliferation, clone formation, apoptosis, migration and invasion were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, clone formation, flow cytometry and Transwell^® migration and invasion assays, respectively. In vivo xenotransplantation was utilized to determine the effect of miR-652 on GBM tumor growth in vivo. Of note, the molecular mechanisms underlying the tumor-suppressing activity of miR-652 upregulation in GBM cells were also investigated using a series of experiments, including bioinformatics analysis, luciferase reporter assay, RT-qPCR and Western blot analysis.

Results

miR-652 expression was considerably downregulated in GBM tissues and cell lines. Low miR-652 expression was strongly correlated with Karnofsky performance score and tumor size. Overall survival duration was shorter in GBM patients with low miR-652 expression than in those with high miR-652 expression. miR-652 resumption considerably suppressed the proliferation, clone formation, migration, and invasion and promoted the apoptosis of GBM cells in vitro. In addition, forkhead-box k1 (FOXK1) was demonstrated as the direct target gene of miR-652 in GBM cells. FOXK1 downregulation led to a tumor-suppressing activity similar to that of miR-652 upregulation. Restoration of FOXK1 expression partially neutralized the influence of miR-652 overexpression on GBM cells. Furthermore, ectopic miR-652 expression deactivated the AKT/mTOR pathway in GBM cells via FOXK1 regulation. Moreover, miR-652 impaired GBM tumor growth in vivo, probably caused by miR-652-mediated suppression of FOXK1/AKT/mTOR signaling.

Conclusion

miR-652 inhibits FOXK1 and deactivates the AKT/mTOR pathway, thereby resulting in the suppression of malignant phenotypes of GBM cells in vitro and in vivo.

Identification of Insulin-Responsive Transcription Factors That Regulate Glucose Production by Hepatocytes

Hepatocyte glucose production is a complex process that integrates cell-autonomous mechanisms with cellular signaling, enzyme activity modulation, and gene transcription. Transcriptional mechanisms controlling glucose production are redundant and involve nuclear hormone receptors and unliganded transcription factors (TFs). Our knowledge of this circuitry is incomplete. Here we used DNA affinity purification followed by mass spectrometry to probe the network of hormone-regulated TFs by using phosphoenolpyruvate carboxykinase (Pck1) and glucose-6-phosphatase (G6pc) in liver and primary hepatocytes as model systems. The repertoire of insulin-regulated TFs is unexpectedly broad and diverse. Whereas in liver the two test promoters are regulated by largely overlapping sets of TFs, in primary hepatocytes Pck1 and G6pc regulation diverges. Insulin treatment preferentially results in increased occupancy by the two promoters, consistent with a model in which the hormone's primary role is to recruit corepressors rather than to clear activators. Nine insulin-responsive TFs are present in both models, but only FoxK1, FoxA2, ZFP91, and ZHX3 require an intact Pck1p insulin response sequence for binding. Knockdown of FoxK1 in primary hepatocytes decreased both glucose production and insulin's ability to suppress it. The findings expand the repertoire of insulin-dependent TFs and identify FoxK1 as a contributor to insulin signaling.

Chromatin remodeling factor BAZ1A regulates cellular senescence in both cancer and normal cells

AIMS

Cellular senescence is a well-known cancer prevention mechanism, inducing cancer cells to senescence can enhance cancer immunotherapy. However, how cellular senescence is regulated is not fully understood. Dynamic chromatin changes have been discovered during cellular senescence, while the causality remains elusive. BAZ1A, a gene coding the accessory subunit of ATP-dependent chromatin remodeling complex, showed decreased expression in multiple cellular senescence models. We aim to investigate the functional role of BAZ1A in regulating senescence in cancer and normal cells.

MATERIALS AND METHODS

Knockdown of BAZ1A was performed via lentivirus mediated short hairpin RNA (shRNA) in various cancer cell lines (A549 and U2OS) and normal cells (HUVEC, NIH3T3 and MEF). A series of senescence-associated phenotypes were quantified by CCK-8 assay, SA-β-Gal staining and EdU incorporation assay, etc. KEY FINDINGS: Knockdown (KD) of BAZ1A induced series of senescence-associated phenotypes in both cancer and normal cells. BAZ1A-KD caused the upregulated expression of SMAD3, which in turn activated the transcription of p21 coding gene CDKN1A and resulted in senescence-associated phenotypes in human cancer cells (A549 and U2OS).

SIGNIFICANCE

Our results revealed chromatin remodeling modulator BAZ1A acting as a novel regulator of cellular senescence in both normal and cancer cells, indicating a new target for potential cancer treatment.

New antiproliferative germacranolides from Carpesium divaricatum

Six new highly oxygenated (2–7) and one known (1) germacranolides were isolated from the whole plant of Carpesium divaricatum. The planar structures and relative configurations of the new compounds were determined by detailed spectroscopic analysis. The absolute configurations of 1 and 3 were established by circular dichroism (CD) and X-ray crystallographic analyses, and the stereochemistry of the new compounds 2 and 4–6 were determined by similar CD data to 1 and 3, respectively. All isolates were evaluated for their antiproliferative activities against three human tumor cell lines, and compounds 3 and 6 show antiproliferative activities against HeLa and Hep G2 cells with IC₅₀ values of 4.13–8.37 μM. Intensive mechanism study showed that 3 caused cell-cycle arrest at the S/G2 phase and induced apoptosis in Hep G2 cells through a mitochondria-related pathway.

A new compound from Carpesium divaricatum has the potential to treat liver cancer through apoptosis induction and cell cycle arrest.