ZHX2 inhibits SREBP1c-mediated de novo lipogenesis in hepatocellular carcinoma via miR-24-3p

Lipogenesis and MASLD: re-thinking the role of SREBPs

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide and a major risk factor for hepatocellular carcinoma (HCC). Lipid metabolism, particularly de novo lipogenesis (DNL) regulated by sterol regulatory element-binding proteins (SREBPs), plays a key role in MASLD progression. While excessive SREBP activation contributes to hepatic steatosis, our recent findings indicate that strong SREBP inhibition paradoxically exacerbates liver injury and accelerates carcinogenesis in murine MASLD models. Mechanistically, SREBP dysfunction disrupts phospholipid homeostasis, leading to impaired endoplasmic reticulum (ER) membrane fluidity, ER stress, and hepatocyte injury. Transcriptomic analysis of clinical samples revealed a dynamic shift in SREBP activity, with upregulation in early MASLD but significant downregulation in advanced, burned-out MASH. This suggests that SREBP dysfunction in advanced disease may contribute to fibrosis progression and increased HCC risk. Given these findings, therapeutic strategies targeting lipid metabolism in MASLD must be carefully tailored to disease stage. This review provides an updated perspective on the biphasic role of SREBP in MASLD, emphasizing the need to re-think lipid metabolism-targeted therapies and develop personalized interventions to mitigate disease progression and HCC development.

IRX5 Promoted SREBP1-Mediated de Novo Fatty Acid Synthesis via HMGN4 in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), a prevalent malignant tumour, ranks highly in both morbidity and mortality, and its prevention and treatment need further studies. The transcription factor iroquois homeobox 5 (IRX5) plays an essential role in HCC, whereas little is known about its exact functions and underlying mechanisms in tumour metabolism reprogramming. Besides, as a transcription factor that mainly locates in nuclei, IRX5 lacks a nuclear localisation sequence, which makes uncovering the mechanism of IRX5 translocating into the nuclei of great significance. Here, we first found that both IRX5 and HCC development are highly expressed; IRX5 accelerates de novo fatty acid synthesis and promotes cancer cell proliferation and progression. Moreover, the GST pull-down combined with GC/MS experiments identified an interaction between IRX5 and high-mobility group nucleosomal binding domain 4 (HMGN4). Immunofluorescence analysis showed that IRX5 and HMGN4 colocalised within the nucleus. Coimmunoprecipitation further confirmed their direct interaction. The elevated expression of HMGN4 enhanced the nuclear transport of IRX5. Taken together, our observations suggest that HMGN4 driving IRX5 nuclear translocation promotes HCC development via de novo fatty acid synthesis reprogramming.

STAMBPL1, transcriptionally regulated by SREBP1, promotes malignant behaviors of hepatocellular carcinoma cells via Wnt/β-catenin signaling pathway

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death worldwide. STAM binding protein-like 1 (STAMBPL1), a key member of the COP9 signalosome subunit 5/serine protease 27/proteasome 26S subunit non-ATPase 7 (JAMM) family, is closely associated with tumor development. In this work, data from GSE101728 and GSE84402 chips were analyzed, and STAMBPL1 was selected as the target factor. This study aimed to reveal the potential function of STAMBPL1 in HCC. Clinical results showed that STAMBPL1 was significantly increased in tumor tissues of HCC patients, and its expression was strongly associated with tumor size and TNM stage. Furthermore, STAMBPL1-overexpressed Hep3B2.1-7 cell line or STAMBPL1-silenced SNU-182 cell line were established using lentivirus carrying cDNA encoding STAMBPL1 mRNA or shRNA targeting STAMBPL1, respectively. STAMBPL1-overexpressed cells exhibited a pronounced enhancement of proliferation in vitro and in vivo. Exogenous expression of STAMBPL1 increased the percentage of cells in the S phase and upregulated the expressions of CyclinD1 and Survivin. As expected, STAMBPL1 knockdown exhibited completely opposite effects, resulting in impaired tumorigenicity in vitro and in vivo. Mechanistically, STAMBPL1 activated Wnt/β-catenin pathway and increased the expression of downstream cancer-promoting genes. Interestingly, we found that STAMBPL1 was transcriptionally regulated by sterol regulatory element-binding protein 1 (SREBP1), a modulator of lipid metabolism, as evidenced by luciferase reporter and chromatin-immunoprecipitation (Ch-IP) assays. Notably, STAMBPL1 overexpression increased lipid accumulation in HCC cells and xenograft tumors. Totally our findings suggest that STAMBPL1 plays a vital role in the tumorigenicity of HCC cells. Modulation of Wnt/β-catenin and lipid metabolism may contribute to its pro-cancer effects. STAMBPL1 may serve as a therapeutic target of HCC.

METTL3 and IGF2BP1-Mediated m6A Modification of ZHX2 Promotes Tumor Property of Renal Cell Carcinoma

INTRODUCTION

Renal cell carcinoma (RCC) is a common type of kidney cancer with limited treatment options and a high mortality rate. Therefore, it is essential to understand the role and mechanism of key genes in RCC development and progression. This study aimed to analyze the role of zinc fingers and homeoboxes 2 (ZHX2) in RCC and the underlying mechanism.

METHODS

RNA expression was analyzed by quantitative real-time polymerase chain reaction, while protein expression was analyzed by Western blotting assay and immunohistochemistry assay. Cell viability was evaluated using CCK-8 assay, and cell proliferation was assessed by EdU assay. The rate of cell apoptosis was quantified by flow cytometry. Transwell assays were conducted to analyze cell migration and invasion. The sphere formation assay was performed to assess the formation of microspheres. Additionally, m6A RNA immunoprecipitation assay and RNA immunoprecipitation assay were utilized to investigate the relationship between ZHX2 and two proteins, methyltransferase like 3 (METTL3) and insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1). The stability of ZHX2 mRNA was analyzed through the Actinomycin D assay. Furthermore, a xenograft mouse model assay was conducted to analyze the effect of ZHX2 overexpression and METTL3 silencing on RCC cell tumor properties in vivo.

RESULTS

ZHX2 expression was upregulated in both RCC tissues and cells when compared with healthy renal tissues and human renal cortex proximal convoluted tubule epithelial cells. Depletion of ZHX2 inhibited RCC cell proliferation, migration, invasion, and spheroid-forming capacity but promoted cell apoptosis. Moreover, it was found that METTL3-mediated m6A methylation of ZHX2 and IGF2BP1 also stabilized ZHX2 through m6A methylation modification. Furthermore, ZHX2 overexpression showed a potential for attenuating the effects induced by METTL3 silencing and counteracted the inhibitory effect of METTL3 depletion on tumor formation in vivo.

CONCLUSION

METTL3 and IGF2BP1-mediated m6A modification of ZHX2 promoted RCC progression. The finding suggests that ZHX2 may serve as a potential therapeutic target in RCC, providing valuable insights for future clinical interventions.

Role of lipid metabolism in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), an aggressive malignancy with a dismal prognosis, poses a significant public health challenge. Recent research has highlighted the crucial role of lipid metabolism in HCC development, with enhanced lipid synthesis and uptake contributing to the rapid proliferation and tumorigenesis of cancer cells. Lipids, primarily synthesized and utilized in the liver, play a critical role in the pathological progression of various cancers, particularly HCC. Cancer cells undergo metabolic reprogramming, an essential adaptation to the tumor microenvironment (TME), with fatty acid metabolism emerging as a key player in this process. This review delves into intricate interplay between HCC and lipid metabolism, focusing on four key areas: de novo lipogenesis, fatty acid oxidation, dysregulated lipid metabolism of immune cells in the TME, and therapeutic strategies targeting fatty acid metabolism for HCC treatment.

Toosendanin induces hepatotoxicity via disrupting LXRα/Lipin1/SREBP1 mediated lipid metabolism

Toosendanin (TSN) is the main active compound derived from Melia toosendan Sieb et Zucc with various bioactivities. However, liver injury was observed in TSN limiting its clinical application. Lipid metabolism plays a crucial role in maintaining cellular homeostasis, and its disruption is also essential in TSN-induced hepatotoxicity. This study explored the hepatotoxicity caused by TSN in vitro and in vivo. The lipid droplets were significantly decreased, accompanied by a decrease in fatty acid transporter CD36 and crucial enzymes in the lipogenesis including ACC and FAS after the treatment of TSN. It was suggested that TSN caused lipid metabolism disorder in hepatocytes. TOFA, an allosteric inhibitor of ACC, could partially restore cell survival via blocking malonyl-CoA accumulation. Notably, TSN downregulated the LXRα/Lipin1/SREBP1 signaling pathway. LXRα activation improved cell survival and intracellular neutral lipid levels, while SREBP1 inhibition aggravated the cell damage and caused a further decline in lipid levels. Male Balb/c mice were treated with TSN (5, 10, 20 mg/kg/d) for 7 days. TSN exposure led to serum lipid levels aberrantly decreased. Moreover, the western blotting results showed that LXRα/Lipin1/SREBP1 inhibition contributed to TSN-induced liver injury. In conclusion, TSN caused lipid metabolism disorder in liver via inhibiting LXRα/Lipin1/SREBP1 signaling pathway.

miRNA-seq analysis of liver tissue from largemouth bass (Micropterus salmoides) in response to oxytetracycline and enzyme-treated soy protein

The specific miRNA regulation triggered by enzyme-treated soybean protein in response to well-known stressors, such as the prophylactic use of the antimicrobial oxytetracycline, remains unknown. Hence, this study aimed to evaluate the regulatory changes of hepatic miRNAs induced by oxytetracycline and enzyme-treated soybean protein in largemouth bass dietary formulations. The experiment was designed with three groups: the normal control (NC), the oxytetracycline exposure treatment group (OTC), and the pre-treatment with enzyme-treated soybean protein before oxytetracycline exposure group (ETSP). miRNA sequencing was employed to characterize the differences between these groups. In conclusion, the NC group exhibited up-regulation of 13 host miRNAs and down-regulation of 1 miRNA compared to the OTC group, whereas the ETSP group showed an increasing trend of 36 host miRNAs and a decreasing trend of 13 host miRNAs compared to the OTC group. Nine miRNAs were identified as prudential targets for enzyme-treated soy protein, protecting the largemouth bass liver from oxytetracycline. Furthermore, gene ontology analysis revealed nine key miRNAs that mediate signaling pathways with significant differences. The cellular lipid metabolic process was identified as the most important biological process, and the propanoate metabolism pathway was highlighted as significant. These results will facilitate further exploration of the mechanism by which enzyme-treated soy protein alleviates the effects of oxytetracycline on largemouth bass in water environments.

Lipid Metabolism as a Potential Target of Liver Cancer

Hepatocellular carcinoma (HCC) stands as a severe malignant tumor with a profound impact on overall health, often accompanied by an unfavorable prognosis. Despite some advancements in the diagnosis and treatment of this disease, improving the prognosis of HCC remains a formidable challenge. It is noteworthy that lipid metabolism plays a pivotal role in the onset, development, and progression of tumor cells. Existing research indicates the potential application of targeting lipid metabolism in the treatment of HCC. This review aims to thoroughly explore the alterations in lipid metabolism in HCC, offering a detailed account of the potential advantages associated with innovative therapeutic strategies targeting lipid metabolism. Targeting lipid metabolism holds promise for potentially enhancing the prognosis of HCC.

Pharmacological therapy of metabolic dysfunction-associated steatotic liver disease-driven hepatocellular carcinoma

In light of a global rise in the number of patients with type 2 diabetes mellitus (T2DM) and obesity, non-alcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction-associated fatty liver disease (MAFLD) or metabolic dysfunction-associated steatotic liver disease (MASLD), has become the leading cause of hepatocellular carcinoma (HCC), with the annual occurrence of MASLD-driven HCC expected to increase by 45%-130% by 2030. Although MASLD has become a serious major public health threat globally, the exact molecular mechanisms mediating MASLD-driven HCC remain an open problem, necessitating future investigation. Meanwhile, emerging studies are focusing on the utility of bioactive compounds to halt the progression of MASLD to MASLD-driven HCC. In this review, we first briefly review the recent progress of the possible mechanisms of pathogenesis and progression for MASLD-driven HCC. We then discuss the application of bioactive compounds to mitigate MASLD-driven HCC through different modulatory mechanisms encompassing anti-inflammatory, lipid metabolic, and gut microbial pathways, providing valuable information for future treatment and prevention of MASLD-driven HCC. Nonetheless, clinical research exploring the effectiveness of herbal medicines in the treatment of MASLD-driven HCC is still warranted.

Targeting metabolic reprogramming in hepatocellular carcinoma to overcome therapeutic resistance: A comprehensive review

Hepatocellular carcinoma (HCC) poses a heavy burden on human health with high morbidity and mortality rates. Systematic therapy is crucial for advanced and mid-term HCC, but faces a significant challenge from therapeutic resistance, weakening drug effectiveness. Metabolic reprogramming has gained attention as a key contributor to therapeutic resistance. Cells change their metabolism to meet energy demands, adapt to growth needs, or resist environmental pressures. Understanding key enzyme expression patterns and metabolic pathway interactions is vital to comprehend HCC occurrence, development, and treatment resistance. Exploring metabolic enzyme reprogramming and pathways is essential to identify breakthrough points for HCC treatment. Targeting metabolic enzymes with inhibitors is key to addressing these points. Inhibitors, combined with systemic therapeutic drugs, can alleviate resistance, prolong overall survival for advanced HCC, and offer mid-term HCC patients a chance for radical resection. Advances in metabolic research methods, from genomics to metabolomics and cells to organoids, help build the HCC metabolic reprogramming network. Recent progress in biomaterials and nanotechnology impacts drug targeting and effectiveness, providing new solutions for systemic therapeutic drug resistance. This review focuses on metabolic enzyme changes, pathway interactions, enzyme inhibitors, research methods, and drug delivery targeting metabolic reprogramming, offering valuable references for metabolic approaches to HCC treatment.

SREBP Regulation of Lipid Metabolism in Liver Disease, and Therapeutic Strategies

Sterol regulatory element-binding proteins (SREBPs) are master transcription factors that play a crucial role in regulating genes involved in the biogenesis of cholesterol, fatty acids, and triglycerides. As such, they are implicated in several serious liver diseases, including non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma (HCC). SREBPs are subject to regulation by multiple cofactors and critical signaling pathways, making them an important target for therapeutic interventions. In this review, we first introduce the structure and activation of SREBPs, before focusing on their function in liver disease. We examine the mechanisms by which SREBPs regulate lipogenesis, explore how alterations in these processes are associated with liver disease, and evaluate potential therapeutic strategies using small molecules, natural products, or herb extracts that target these pathways. Through this analysis, we provide new insights into the versatility and multitargets of SREBPs as factors in the modulation of different physiological stages of liver disease, highlighting their potential targets for therapeutic treatment.

ZHX2 emerges as a negative regulator of mitochondrial oxidative phosphorylation during acute liver injury

Mitochondria dysfunction contributes to acute liver injuries, and mitochondrial regulators, such as PGC-1α and MCJ, affect liver regeneration. Therefore, identification of mitochondrial modulators may pave the way for developing therapeutic strategies. Here, ZHX2 is identified as a mitochondrial regulator during acute liver injury. ZHX2 both transcriptionally inhibits expression of several mitochondrial electron transport chain genes and decreases PGC-1α stability, leading to reduction of mitochondrial mass and OXPHOS. Loss of Zhx2 promotes liver recovery by increasing mitochondrial OXPHOS in mice with partial hepatectomy or CCl4-induced liver injury, and inhibition of PGC-1α or electron transport chain abolishes these effects. Notably, ZHX2 expression is higher in liver tissues from patients with drug-induced liver injury and is negatively correlated with mitochondrial mass marker TOM20. Delivery of shRNA targeting Zhx2 effectively protects mice from CCl4-induced liver injury. Together, our data clarify ZHX2 as a negative regulator of mitochondrial OXPHOS and a potential target for developing strategies for improving liver recovery after acute injuries.

Characterization of circSEC11A as a novel regulator of Iodine-125 radioactive seed-induced anticancer effects in hepatocellular carcinoma via targeting ZHX2/GADD34 axis

Iodine-125 (I-125) radioactive seed implantation is used for the local treatment of hepatocellular carcinoma (HCC), but the molecular mechanisms regulating its anticancer effects remain incompletely understood. In this study, we report that hsa_circ_0000647 (circSEC11A) is highly expressed after I-125 treatment in HCC cell lines and tissues and is a key regulator of I-125-induced anticancer effects. CircSEC11A acts as a competing endogenous RNA (ceRNA) to sponge miR-3529-3p, promoting the expression of zinc fingers and homeoboxes 2 (ZHX2) and enhancing I-125-induced anticancer effects. Dual-luciferase reporter assay, RNA pull-down, RNA immunoprecipitation, and fluorescence in situ hybridization were thereafter performed to verify the interaction among the molecules. Anticancer effects were detected using CCK-8, flow cytometry, TUNEL, EdU, transwell, and wound healing assays. Furthermore, ZHX2 transcriptionally inhibits GADD34, a negative regulator of endoplasmic reticulum stress (ERS), to enhance I-125- induced anticancer effects in vivo and in vitro. In conclusion, we characterized circSEC11A as a novel regulator of I-125-induced anticancer effects in HCC via miR-3529-3p/ZHX2/GADD34 axis-mediated ERS. Thus, circSEC11A may act as a potential therapeutic target for I-125 implantation in the clinic.

Cooperative regulation of Zhx1 and hnRNPA1 drives the cardiac progenitor-specific transcriptional activation during cardiomyocyte differentiation

The zinc finger proteins (ZNFs) mediated transcriptional regulation is critical for cell fate transition. However, it is still unclear how the ZNFs realize their specific regulatory roles in the stage-specific determination of cardiomyocyte differentiation. Here, we reported that the zinc fingers and homeoboxes 1 (Zhx1) protein, transiently expressed during the cell fate transition from mesoderm to cardiac progenitors, was indispensable for the proper cardiomyocyte differentiation of mouse and human embryonic stem cells. Moreover, Zhx1 majorly promoted the specification of cardiac progenitors via interacting with hnRNPA1 and co-activated the transcription of a wide range of genes. In-depth mechanistic studies showed that Zhx1 was bound with hnRNPA1 by the amino acid residues (Thr111-His120) of the second Znf domain, thus participating in the formation of cardiac progenitors. Together, our study highlights the unrevealed interaction of Zhx1/hnRNPA1 for activating gene transcription during cardiac progenitor specification and also provides new evidence for the specificity of cell fate determination in cardiomyocyte differentiation.

The functions and roles of C2H2 zinc finger proteins in hepatocellular carcinoma

C2H2 zinc finger (C2H2-ZF) proteins are the majority group of human transcription factors and they have many different molecular functions through different combinations of zinc finger domains. Hepatocellular carcinoma (HCC) is one of the most prevalent malignant tumors and the main reason for cancer-related deaths worldwide. More and more findings support the abnormal expression of C2H2-ZF protein in the onset and progression of HCC. The C2H2-ZF proteins are involved in various biological functions in HCC, such as EMT, stemness maintenance, metabolic reprogramming, cell proliferation and growth, apoptosis, and genomic integrity. The study of anti-tumor drug resistance also highlights the pivotal roles of C2H2-ZF proteins at the intersection of biological functions (EMT, stemness maintenance, autophagy)and chemoresistance in HCC. The involvement of C2H2-ZF protein found recently in regulating different molecules, signal pathways and pathophysiological activities indicate these proteins as the possible therapeutic targets, and diagnostic or prognostic biomarkers for HCC.

ncRNA-mediated fatty acid metabolism reprogramming in HCC

The challenges of hepatocellular carcinoma (HCC) pathogenesis, diagnosis, treatment, and prognosis evaluation are obvious. Hepatocyte-specific fatty acid (FA) metabolic reprogramming is an important marker of liver carcinogenesis and progression; elucidating its mechanism will help unravel the complexity of HCC pathogenesis. Noncoding RNAs (ncRNAs) play important roles in HCC development. Moreover, ncRNAs are important mediators of FA metabolism and are directly involved in the reprogramming of FA metabolism in HCC cells. Here we review significant new advances in understanding the mechanisms regulating HCC metabolism by focusing on ncRNA-mediated post-translational modifications of metabolic enzymes, metabolism-related transcription factors, and other proteins in associated signaling pathways. We also discuss the great therapeutic potential of targeting ncRNA-mediated FA metabolism reprogramming in HCC.

Zinc fingers and homeoboxes 2 is required for diethylnitrosamine-induced liver tumor formation in C57BL/6 mice

Liver cancer, comprised primarily of hepatocellular carcinoma (HCC), is the third leading cause of cancer deaths worldwide and increasing in Western countries. We previously identified the transcription factor zinc fingers and homeoboxes 2 (Zhx2) as a regulator of hepatic gene expression, and many Zhx2 target genes are dysregulated in HCC. Here, we investigate HCC in Zhx2-deficient mice using the diethylnitrosamine (DEN)-induced liver tumor model. Our study using whole-body Zhx2 knockout (Zhx2KO ) mice revealed the complete absence of liver tumors 9 and 10 months after DEN exposure. Analysis soon after DEN treatment showed no differences in expression of the DEN bioactivating enzyme cytochrome P450 2E1 (CYP2E1) and DNA polymerase delta 2, or in the numbers of phosphorylated histone variant H2AX foci between Zhx2KO and wild-type (Zhx2wt ) mice. The absence of Zhx2, therefore, did not alter DEN bioactivation or DNA damage. Zhx2KO livers showed fewer positive foci for Ki67 staining and reduced interleukin-6 and AKT serine/threonine kinase 2 expression compared with Zhx2wt livers, suggesting that Zhx2 loss reduces liver cell proliferation and may account for reduced tumor formation. Tumors were reduced but not absent in DEN-treated liver-specific Zhx2 knockout mice, suggesting that Zhx2 acts in both hepatocytes and nonparenchymal cells to inhibit tumor formation. Analysis of data from the Cancer Genome Atlas and Clinical Proteomic Tumor Consortium indicated that ZHX2 messenger RNA and protein levels were significantly higher in patients with HCC and associated with clinical pathological parameters. Conclusion: In contrast to previous studies in human hepatoma cell lines and other HCC mouse models showing that Zhx2 acts as a tumor suppressor, our data indicate that Zhx2 acts as an oncogene in the DEN-induced HCC model and is consistent with the higher ZHX2 expression in patients with HCC.

ZHX2 in health and disease

As a transcriptional factor and the negative regulator of alpha fetal protein (AFP), Zinc fingers and homeoboxes 2 (ZHX2) has a well-established role in protection against hepatocellular carcinoma (HCC). However, recent studies have suggested ZHX2 as an oncogene in clear cell renal cell carcinoma (ccRCC) and triple-negative breast cancer (TNBC). Moreover, mounting evidence has illustrated a much broader role of ZHX2 in multiple cellular processes, including cell proliferation, cell differentiation, lipid metabolism, and immunoregulation. This comprehensive review emphasizes the role of ZHX2 in health and diseases which have been more recently uncovered.

LINC01468 drives NAFLD-HCC progression through CUL4A-linked degradation of SHIP2

Accumulating evidence suggests that long noncoding RNAs (lncRNAs) are deregulated in hepatocellular carcinoma (HCC) and play a role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). However, the current understanding of the role of lncRNAs in NAFLD-associated HCC is limited. In this study, transcriptomic profiling analysis of three paired human liver samples from patients with NAFLD-driven HCC and adjacent samples showed that LINC01468 expression was significantly upregulated. In vitro and in vivo gain- and loss-of-function experiments showed that LINC01468 promotes the proliferation of HCC cells through lipogenesis. Mechanistically, LINC01468 binds SHIP2 and promotes cullin 4 A (CUL4A)-linked ubiquitin degradation, thereby activating the PI3K/AKT/mTOR signaling pathway, resulting in the promotion of de novo lipid biosynthesis and HCC progression. Importantly, the SHIP2 inhibitor reversed the sorafenib resistance induced by LINC01468 overexpression. Moreover, ALKBH5-mediated N6-methyladenosine (m6A) modification led to stabilization and upregulation of LINC01468 RNA. Taken together, the findings indicated a novel mechanism by which LINC01468-mediated lipogenesis promotes HCC progression through CUL4A-linked degradation of SHIP2. LINC01468 acts as a driver of HCC progression from NAFLD, highlights the potential of the LINC01468-SHIP2 axis as a therapeutic target for HCC.

Zinc Fingers and Homeobox Family in Cancer: A Double-Edged Sword

The zinc fingers and homeobox (ZHX) family includes ZHX1, ZHX2, and ZHX3, and their proteins have similar unique structures, containing two C2H2-type zinc finger motifs and four or five HOX-like homeodomains. The members of the ZHX family can form homodimers or heterodimers with each other or with a subunit of nuclear factor Y. Previous studies have suggested that ZHXs can function as positive or negative transcriptional regulators. Recent studies have further revealed their biological functions and underlying mechanisms in cancers. This review summarized the advances of ZHX-mediated functions, including tumor-suppressive and oncogenic functions in cancer formation and progression, the molecular mechanisms, and regulatory functions, such as cancer cell proliferation, migration, invasion, and metastasis. Moreover, the differential expression levels and their association with good or poor outcomes in patients with various malignancies and differential responses to chemotherapy exert opposite functions of oncogene or tumor suppressors. Therefore, the ZHXs act as a double-edged sword in cancers.

Metabolic Reprogramming in Hematologic Malignancies: Advances and Clinical Perspectives

Metabolic reprogramming is a hallmark of cancer progression. Metabolic activity supports tumorigenesis and tumor progression, allowing cells to uptake essential nutrients from the environment and use the nutrients to maintain viability and support proliferation. The metabolic pathways of malignant cells are altered to accommodate increased demand for energy, reducing equivalents, and biosynthetic precursors. Activated oncogenes coordinate with altered metabolism to control cell-autonomous pathways, which can lead to tumorigenesis when abnormalities accumulate. Clinical and preclinical studies have shown that targeting metabolic features of hematologic malignancies is an appealing therapeutic approach. This review provides a comprehensive overview of the mechanisms of metabolic reprogramming in hematologic malignancies and potential therapeutic strategies to target cancer metabolism.

Targeting SREBP-1-Mediated Lipogenesis as Potential Strategies for Cancer

Sterol regulatory element binding protein-1 (SREBP-1), a transcription factor with a basic helix–loop–helix leucine zipper, has two isoforms, SREBP-1a and SREBP-1c, derived from the same gene for regulating the genes of lipogenesis, including acetyl-CoA carboxylase, fatty acid synthase, and stearoyl-CoA desaturase. Importantly, SREBP-1 participates in metabolic reprogramming of various cancers and has been a biomarker for the prognosis or drug efficacy for the patients with cancer. In this review, we first introduced the structure, activation, and key upstream signaling pathway of SREBP-1. Then, the potential targets and molecular mechanisms of SREBP-1-regulated lipogenesis in various types of cancer, such as colorectal, prostate, breast, and hepatocellular cancer, were summarized. We also discussed potential therapies targeting the SREBP-1-regulated pathway by small molecules, natural products, or the extracts of herbs against tumor progression. This review could provide new insights in understanding advanced findings about SREBP-1-mediated lipogenesis in cancer and its potential as a target for cancer therapeutics.

Mesencephalic astrocyte-derived neurotrophic factor alleviates non-alcoholic steatohepatitis induced by Western diet in mice

Excessive lipid accumulation, inflammation, and fibrosis in the liver are the major characteristics of non-alcoholic steatohepatitis (NASH). Mesencephalic astrocyte-derived neurotrophic factor (MANF) plays an important role in metabolic homeostasis, raising the possibility that it is involved in NASH. Here, we reduced and increased MANF levels in mice in order to explore its influence on hepatic triglyceride homeostasis, inflammation, and fibrosis during NASH progression. The MANF expression was decreased in Western diet-induced NASH mice. In vivo, liver-specific MANF knockout exacerbated hepatic lipid accumulation, inflammation, and fibrosis of mice induced by Western diet, while liver-specific MANF overexpression mitigated these NASH pathogenic features. In vitro, knocking down MANF in primary hepatocyte cultures aggravated hepatic steatosis and inflammation, which MANF overexpression markedly attenuated. Studies in vitro and in vivo suggested that MANF regulated hepatic lipid synthesis by modulating SREBP1 expression. Inhibiting SREBP1 in primary hepatocytes blocked lipid accumulation after MANF knockdown. MANF overexpression reversed LXRs agonist GW3965 induced SREBP1 and LIPIN1 expression. MANF decreased the expression of pro-inflammatory cytokines by inhibiting NF-κB phosphorylation. These results suggest that MANF can protect against NASH by regulating SREBP1 expression and NF-κB signaling.

Epigallocatechin gallate triggers apoptosis by suppressing de novo lipogenesis in colorectal carcinoma cells

The de novo lipogenesis (DNL) pathway has been identified as a regulator of cancer progression and aggressiveness. Downregulation of key lipogenesis enzymes has been shown to activate apoptosis in cancerous cells. Epigallocatechin gallate (EGCG) inhibits cancer cell proliferation without causing cytotoxicity in healthy cells. The present study aimed to investigate the effects of EGCG on the promotion of apoptosis associated with the DNL pathway inhibition in cancer cells, both in vitro and in vivo. We observed that two colorectal cancer cell lines (HCT116 and HT-29) had a higher cytotoxic response to EGCG treatment than hepatocellular carcinoma cells, including HepG2 and HuH-7. EGCG treatment decreased cell viability and increased mitochondrial damage-triggered apoptosis in both HCT116 and HT-29 cancer cells. Additionally, we treated mice transplanted with HCT116 cells with 30 or 50 mg·kg-1 EGCG for 7 days to evaluate the apoptotic effects of EGCG treatment in a xenograft mouse model of cancer. We observed a decrease in intracellular fatty acid levels, which suggested that EGCG-induced apoptosis was associated with a decrease in fatty acid levels in cancer. Suppression of ATP synthesis by EGCG indicated that cell death induction in cancer cells could be mediated by shared components of the DNL and energy metabolism pathways. In addition, EGCG-induced apoptosis suppressed the expression of the phosphorylation protein kinase B and extracellular signal-regulated kinase 1/2 signaling proteins in tumors from xenografted mice. Cytotoxic effects in unaffected organs and tissues of the mouse xenograft model were absent upon EGCG treatment.

The miR-23-27-24 cluster: an emerging target in NAFLD pathogenesis

The incidence of non-alcoholic fatty liver disease (NAFLD) is increasing globally, being the most widespread form of chronic liver disease in the west. NAFLD includes a variety of disease states, the mildest being non-alcoholic fatty liver that gradually progresses to non-alcoholic steatohepatitis, fibrosis, cirrhosis, and eventually hepatocellular carcinoma. Small non-coding single-stranded microRNAs (miRNAs) regulate gene expression at the miRNA or translational level. Numerous miRNAs have been shown to promote NAFLD pathogenesis and progression through increasing lipid accumulation, oxidative stress, mitochondrial damage, and inflammation. The miR-23-27-24 clusters, composed of miR-23a-27a-24-2 and miR-23b-27b-24-1, have been implicated in various biological processes as well as many diseases. Herein, we review the current knowledge on miR-27, miR-24, and miR-23 in NAFLD pathogenesis and discuss their potential significance in NAFLD diagnosis and therapy.

The transcription factor zinc fingers and homeoboxes 2 alleviates NASH by transcriptional activation of phosphatase and tensin homolog

BACKGROUND AND AIMS

NASH, which is a common clinical condition predisposing to advanced liver diseases, has become a worldwide epidemic. A large and growing unmet therapeutic need for this condition reflects incomplete understanding of its pathogenesis. In the current study, we identified a transcription factor, zinc fingers and homeoboxes 2 (ZHX2), in hepatocytes as a protective factor against steatohepatitis.

APPROACH AND RESULTS

We found that hepatic ZHX2 was significantly suppressed in NASH models and steatotic hepatic cells. Hepatocyte-specific ablation of ZHX2 exacerbated NASH-related phenotypes in mice, including lipid accumulation, enhanced inflammation, and hepatic fibrosis. Conversely, hepatocyte-specific overexpression of ZHX2 significantly alleviated the progression of NASH in an experimental setting. Integrated analysis of transcriptomic profiling and chromatin immunoprecipitation sequencing data demonstrated that the phosphatase and tensin homolog (PTEN) was a target gene of ZHX2 in hepatocyte. ZHX2 bound to the promoter of PTEN gene and subsequently promoted the transcription of PTEN, which mediated the beneficial role of ZHX2 against NASH.

CONCLUSIONS

The current findings demonstrate a protective role of ZHX2 against NASH progression by transcriptionally activating PTEN. These findings shed light on the therapeutic potential of targeting ZHX2 for treating NASH and related metabolic disorders.

Role of Lipogenesis Rewiring in Hepatocellular Carcinoma

Metabolic rewiring is one of the hallmarks of cancer. Altered de novo lipogenesis is one of the pivotal metabolic events deregulated in cancers. Sterol regulatory element-binding transcription factor 1 (SREBP1) controls the transcription of major enzymes involved in de novo lipogenesis, including ACLY, ACACA, FASN, and SCD. Studies have shown the increased de novo lipogenesis in human hepatocellular carcinoma (HCC) samples. Multiple mechanisms, such as activation of the AKT/mechanistic target of rapamycin (mTOR) pathway, lead to high SREBP1 induction and the coordinated enhanced expression of ACLY, ACACA, FASN, and SCD genes. Subsequent functional analyses have unraveled these enzymes' critical role(s) and the related de novo lipogenesis in hepatocarcinogenesis. Importantly, targeting these molecules might be a promising strategy for HCC treatment. This paper comprehensively summarizes de novo lipogenesis rewiring in HCC and how this pathway might be therapeutically targeted.

Inhibition of SREBP-1 Activation by a Novel Small-Molecule Inhibitor Enhances the Sensitivity of Hepatocellular Carcinoma Tissue to Radiofrequency Ablation

Radiofrequency ablation (RFA) is an important strategy for treatment of advanced hepatocellular carcinoma (HCC). However, the prognostic indicators of RFA therapy are not known, and there are few strategies for RFA sensitization. The transcription factor sterol regulatory element binding protein 1 (SREBP)-1 regulates fatty-acid synthesis but also promotes the proliferation or metastasis of HCC cells. Here, the clinical importance of SREBP-1 and potential application of knockdown of SREBP-1 expression in RFA of advanced HCC was elucidated. In patients with advanced HCC receiving RFA, a high level of endogenous SREBP-1 expression correlated to poor survival. Inhibition of SREBP-1 activation using a novel small-molecule inhibitor, SI-1, not only inhibited the aerobic glycolysis of HCC cells, it also enhanced the antitumor effects of RFA on xenograft tumors. Overall, our results: (i) revealed the correlation between SREBP-1 and HCC severity; (ii) indicated that inhibition of SREBP-1 activation could be a promising approach for treatment of advanced HCC.

The Emerging Factors and Treatment Options for NAFLD-Related Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, followed by cholangiocarcinoma (CCA). HCC is the third most common cause of cancer death worldwide, and its incidence is rising, associated with an increased prevalence of obesity and nonalcoholic fatty liver disease (NAFLD). However, current treatment options are limited. Genetic factors and epigenetic factors, influenced by age and environment, significantly impact the initiation and progression of NAFLD-related HCC. In addition, both transcriptional factors and post-transcriptional modification are critically important for the development of HCC in the fatty liver under inflammatory and fibrotic conditions. The early diagnosis of liver cancer predicts curative treatment and longer survival. However, clinical HCC cases are commonly found in a very late stage due to the asymptomatic nature of the early stage of NAFLD-related HCC. The development of diagnostic methods and novel biomarkers, as well as the combined evaluation algorithm and artificial intelligence, support the early and precise diagnosis of NAFLD-related HCC, and timely monitoring during its progression. Treatment options for HCC and NAFLD-related HCC include immunotherapy, CAR T cell therapy, peptide treatment, bariatric surgery, anti-fibrotic treatment, and so on. Overall, the incidence of NAFLD-related HCC is increasing, and a better understanding of the underlying mechanism implicated in the progression of NAFLD-related HCC is essential for improving treatment and prognosis.