Foxa1 and Foxa2 are essential for sexual dimorphism in liver cancer. Cell. 2012;148:72-83. [PMID: 22265403 DOI: 10.1016/j.cell.2011.11.026]

ESRP2-microRNA-122 axis promotes the postnatal onset of liver polyploidization and maturation

Hepatocyte polyploidy and maturity are critical to acquiring specialized liver functions. Multiple intracellular and extracellular factors influence ploidy, but how they cooperate temporally to steer liver polyploidization and maturation or how post-transcriptional mechanisms integrate into these paradigms is unknown. Here, we identified an important regulatory hierarchy in which postnatal activation of epithelial splicing regulatory protein 2 (ESRP2) stimulates processing of liver-specific microRNA (miR-122) to facilitate polyploidization, maturation, and functional competence of hepatocytes. By determining transcriptome-wide protein-RNA interactions in vivo and integrating them with single-cell and bulk hepatocyte RNA-seq data sets, we delineated an ESRP2-driven RNA processing program that drives sequential replacement of fetal-to-adult transcript isoforms. Specifically, ESRP2 binds the primary miR-122 host gene transcript to promote its processing/biogenesis. Combining constitutive and inducible ESRP2 gain- and loss-of-function mouse models with miR-122 rescue experiments, we demonstrated that timed activation of ESRP2 augments the miR-122-driven program of cytokinesis failure, ensuring the proper onset and extent of hepatocyte polyploidization.

Two Faces of NOTCH1 in Liver Cancer and Immunotherapy

High NOTCH1 expression inversely correlates with hepatocellular carcinoma tumorigenicity and contributes to better immune checkpoint inhibitor responses in male patients, whereas high NOTCH1 in females coincides with heightened hepatocellular carcinoma incidence and poor immunotherapy responses. Activated NOTCH1 generates enhanced antitumor CD8+ T-cell responses in a sex chromosome-dependent manner and facilitates responsiveness to immunotherapy treatment in males, whereas it drives immune escape in females. See related article by Lindblad et al., p. 495.

Mimicking women's endocrine milieu in mice for women's health-related studies

To improve preclinical studies and their translation, patient-derived xenografts (PDXs) are increasingly used. They have human-specific tumor characteristics and reflect intra and inter-tumor heterogeneity. However, the endocrine milieu differs between humans and host mice. In light of sex-specific cancer biology and a rise in endocrine-related cancers there is an urgent need to correctly reflect the hormonal milieu in PDX models. We show that female mice of NOD.Cg-Prkdc scid Il2rg tm1Wjl /SzJ (NSG) strain widely used for PDXs has 17-β-estradiol (E2) and testosterone (T) levels comparable to C57Bl6 females but higher progesterone (P4) levels. E2 levels are comparable, T levels are lower and P4 levels higher than those observed in postmenopausal women. Ovariectomy increases T to levels observed in postmenopausal women. Subcutaneous E2 and combined E2/P4 silicon pellets provide NSG females with premenopausal ovarian hormone levels. These procedures humanize the endocrine environment of experimental animals, improving PDX relevance in women's health-related research.

Identifying potential signatures of immune cells in hepatocellular carcinoma using integrative bioinformatics approaches and machine-learning strategies

Hepatocellular carcinoma (HCC) is a malignant tumor regulated by the immune system. Immunotherapy using checkpoint inhibitors has shown encouraging outcomes in a subset of HCC patients. The main challenges in checkpoint immunotherapy for HCC are to expand treatment options and to broaden the beneficiary population. Therefore, the search for potential signatures of immune cells is meaningful in the development of immunotherapy for HCC. The HCC related datasets were downloaded from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Differential expression analysis and functional analysis were performed first. Then support vector machine-recursive feature elimination (SVM-RFE), random forests (RF), least absolute shrinkage and selection operation (LASSO), and weighed gene co-expression network analysis (WGCNA) were employed to screen for critical genes, and receiver operating characteristic (ROC) analysis was performed to compare diagnostic performance. Subsequently, single-sample gene set enrichment analysis (ssGSEA) was used to explore the relationship between signatures and immune cells. Finally, we validated the expression of these biomarkers in human HCC samples. 531 overlapping differentially expressed genes (DEGs) were identified. Furthermore, enrichment analysis revealed pathways associated with immune activation processes, immune cell involvement and inflammatory signaling. After using multiple machine-learning strategies, extracellular matrix protein 1 (ECM1), leukemia inhibitory factor receptor (LIFR), sushi repeat containing protein X-linked (SRPX), and thromboxane A2 receptor (TBXA2R) were identified as critical signatures, and exhibited high expression in tumor-adjacent normal tissues. According to the ssGSEA results, ECM1, LIFR, SRPX and TBXA2R were all significantly associated with diverse immune cells, such as monocytes and neutrophils. Moreover, immunostaining of human HCC samples showed that these critical signatures all colocalized with CD14-positive monocytes. Our findings report the potential signatures of immune cells in HCC and confirm that they localize in monocytes of tumor-adjacent normal tissues. ECM1, LIFR, SRPX and TBXA2R could become new potential targets for predictive diagnosis, early intervention and immunotherapy of HCC in the future.

Transcription factors and hormone receptors: Sex‑specific targets for cancer therapy (Review)

Despite advancements in diagnostic and therapeutic technologies, cancer continues to pose a challenge to disease-free longevity in humans. Numerous factors contribute to the onset and progression of cancer, among which sex differences, as an intrinsic biological condition, warrant further attention. The present review summarizes the roles of hormone receptors estrogen receptor α (ERα), estrogen receptor β (ERβ) and androgen receptor (AR) in seven types of cancer: Breast, prostate, ovarian, lung, gastric, colon and liver cancer. Key cancer-related transcription factors known to be activated through interactions with these hormone receptors have also been discussed. To assess the impact of sex hormone receptors on different cancer types, hormone-related transcription factors were analyzed using the SignaLink 3.0 database. Further analysis focused on six key transcription factors: CCCTC-binding factor, forkhead box A1, retinoic acid receptor α, PBX homeobox 1, GATA binding protein 2 and CDK inhibitor 1A. The present review demonstrates that these transcription factors significantly influence hormone receptor activity across various types of cancer, and elucidates the complex interactions between these transcription factors and hormone receptors, offering new insights into their roles in cancer progression. The findings suggest that targeting these common transcription factors could improve the efficacy of hormone therapy and provide a unified approach to treating various types of cancer. Understanding the dual and context-dependent roles of these transcription factors deepens the current understanding of the molecular mechanisms underlying hormone-driven tumor progression and could lead to more effective targeted therapeutic strategies.

Androgen receptor signalling in non-prostatic malignancies: challenges and opportunities

The androgen receptor (AR) signalling pathway has been intensively studied in the context of prostate cancer, where androgen deprivation therapy is part of the standard of care for metastatic disease. By contrast, fewer studies have investigated the impact and translational potential of targeting AR in other cancer types where it is also expressed and functional. In this Review, we discuss the current understanding of AR in non-prostatic cancer types and summarize ongoing AR-directed clinical trials. While different androgen levels contribute to sexual dimorphism in cancer, targeting the AR system could benefit both sexes and help overcome resistance to targeted therapies. However, a bimodal function of AR signalling, which suppresses stromal changes associated with the early stages of cancer development, also needs to be considered. Future research is necessary to scrutinize cellular and molecular mechanisms of action of AR in cancer cells and the tumour microenvironment, to develop selective modulators of AR activity, and to identify patients with non-prostatic cancer who might benefit from targeting this pathway. AR-directed manipulation of host immune cells may offer a promising therapeutic approach for many types of cancers.

Repeated fasting events sensitize enhancers, transcription factor activity and gene expression to support augmented ketogenesis

Mammals withstand frequent and prolonged fasting periods due to hepatic production of glucose and ketone bodies. Because the fasting response is transcriptionally regulated, we asked whether enhancer dynamics impose a transcriptional program during recurrent fasting and whether this generates effects distinct from a single fasting bout. We found that mice undergoing alternate-day fasting (ADF) respond profoundly differently to a following fasting bout compared to mice first experiencing fasting. Hundreds of genes enabling ketogenesis are 'sensitized' (i.e. induced more strongly by fasting following ADF). Liver enhancers regulating these genes are also sensitized and harbor increased binding of PPARα, the main ketogenic transcription factor. ADF leads to augmented ketogenesis compared to a single fasting bout in wild-type, but not hepatocyte-specific PPARα-deficient mice. Thus, we found that past fasting events are 'remembered' in hepatocytes, sensitizing their enhancers to the next fasting bout and augment ketogenesis. Our findings shed light on transcriptional regulation mediating adaptation to repeated signals.

HDI-STARR-seq: Condition-specific enhancer discovery in mouse liver in vivo

BACKGROUND

STARR-seq and other massively-parallel reporter assays are widely used to discover functional enhancers in transfected cell models, which can be confounded by plasmid vector-induced type-I interferon immune responses and lack the multicellular environment and endogenous chromatin state of complex mammalian tissues.

RESULTS

We describe HDI-STARR-seq, which combines STARR-seq plasmid library delivery to the liver, by hydrodynamic tail vein injection (HDI), with reporter RNA transcriptional initiation driven by a minimal Albumin promoter, which we show is essential for mouse liver STARR-seq enhancer activity assayed 7 days after HDI. Importantly, little or no vector-induced innate type-I interferon responses were observed. Comparisons of HDI-STARR-seq activity between male and female mouse livers and in livers from males treated with an activating ligand of the transcription factor (TF) CAR (Nr1i3) identified many condition-dependent enhancers linked to condition-specific gene expression. Further, thousands of active liver enhancers were identified using a high complexity STARR-seq library comprised of ~ 50,000 genomic regions released by DNase-I digestion of mouse liver nuclei. When compared to stringently inactive library sequences, the active enhancer sequences identified were highly enriched for liver open chromatin regions with activating histone marks (H3K27ac, H3K4me1, H3K4me3), were significantly closer to gene transcriptional start sites, and were significantly depleted of repressive (H3K27me3, H3K9me3) and transcribed region histone marks (H3K36me3).

CONCLUSION

HDI-STARR-seq offers substantial improvements over current methodologies for large scale, functional profiling of enhancers, including condition-dependent enhancers, in liver tissue in vivo, and can be adapted to characterize enhancer activities in a variety of species and tissues by selecting suitable tissue- and species-specific promoter sequences.

Intricate roles of estrogen and estrogen receptors in digestive system cancers: a systematic review

Gender disparities are evident across different types of digestive system cancers, which are typically characterized by a lower incidence and mortality rate in females compared to males. This finding suggests a potential protective role of female steroid hormones, particularly estrogen, in the development of these cancers. Estrogen is a well-known sex hormone that not only regulates the reproductive system but also exerts diverse effects on non-reproductive organs mediated through interactions with estrogen receptors (ERs), including the classic (ERα and ERβ) and non-traditional ERs [G protein-coupled estrogen receptor (GPER)]. Recent advances have contributed to our comprehension of the mechanisms underlying ERs in digestive system cancers. In this comprehensive review we summarize the current understanding of the intricate roles played by estrogen and ERs in the major types of digestive system cancers, including hepatocellular, pancreatic, esophageal, gastric, and colorectal carcinoma. Furthermore, we discuss the potential molecular mechanisms underlying ERα, ERβ, and GPER effects, and propose perspectives on innovative therapies and preventive measures targeting the pathways regulated by estrogen and ERs. The roles of estrogen and ERs in digestive system cancers are complicated and depend on the cell type and tissue involved. Additionally, deciphering the intricate roles of estrogen, ERs, and the associated signaling pathways may guide the discovery of novel and tailored therapeutic and preventive strategies for digestive system cancers, eventually improving the care and clinical outcomes for the substantial number of individuals worldwide affected by these malignancies.

Androgens Suppress Corticosteroid Binding Globulin in Male Mice, Affecting the Endocrine Stress Response

Biological sex affects the activity of the hypothalamus-pituitary-adrenal (HPA) axis. However, how androgen deprivation affects this axis remains largely unknown. In this study, we investigated the effect of androgen status on different components of the HPA axis in male mice. Two weeks of androgen deprivation did not affect total plasma corticosterone levels but led to increased pituitary ACTH levels. Stress-induced total plasma corticosterone levels were increased, whereas the suppression of corticosterone after dexamethasone treatment under basal conditions was attenuated. Androgen-deprived mice displayed a 2-fold increase in plasma levels of corticosteroid binding globulin (CBG). A similar increase in CBG was observed in global androgen receptor knock-out animals, compared to wild-type littermates. Androgen deprivation was associated with a 6-fold increase in CBG mRNA in the liver and enhanced transcriptional activity at CBG regulatory regions, as evidenced by increased H3K27 acetylation. We propose that the induction of CBG as a consequence of androgen deprivation, together with the unaltered total corticosterone levels, results in lower free corticosterone levels in plasma. This is further supported by mRNA levels of androgen-independent GR target genes in the liver. The reduction in negative feedback on the HPA axis under basal condition would suffice to explain the enhanced stress reactivity after androgen deprivation. Overall, our data demonstrate that, in mice, tonic androgen receptor activation affects CBG levels in conjunction with effects on gene expression and HPA-axis reactivity.

Sphingosine kinase 2 and p62 regulation are determinants of sexual dimorphism in hepatocellular carcinoma

OBJECTIVE

Hepatocellular carcinoma (HCC) is the third leading cause of cancer mortality, and its incidence is increasing due to endemic obesity. HCC is sexually dimorphic in both humans and rodents with higher incidence in males, although the mechanisms contributing to these correlations remain unclear. Here, we examined the role of sphingosine kinase 2 (SphK2), the enzyme that regulates the balance of bioactive sphingolipid metabolites, sphingosine-1-phosphate (S1P) and ceramide, in gender specific MASH-driven HCC.

METHODS

Male and female mice were fed a high fat diet with sugar water, a clinically relevant model that recapitulates MASH-driven HCC in humans followed by physiological, biochemical cellular and molecular analyses. In addition, correlations with increased risk of HCC recurrence were determined in patients.

RESULTS

Here, we report that deletion of SphK2 protects both male and female mice from Western diet-induced weight gain and metabolic dysfunction without affecting hepatic lipid accumulation or fibrosis. However, SphK2 deficiency decreases chronic diet-induced hepatocyte proliferation in males but increases it in females. Remarkably, SphK2 deficiency reverses the sexual dimorphism of HCC, as SphK2-/- male mice are protected whereas the females develop liver cancer. Only in male mice, chronic western diet induced accumulation of the autophagy receptor p62 and its downstream mediators, the antioxidant response target NQO1, and the oncogene c-Myc. SphK2 deletion repressed these known drivers of HCC development. Moreover, high p62 expression correlates with poor survival in male HCC patients but not in females. In hepatocytes, lipotoxicity-induced p62 accumulation is regulated by sex hormones and prevented by SphK2 deletion. Importantly, high SphK2 expression in male but not female HCC patients is associated with a more aggressive HCC differentiation status and increased risk of cancer recurrence.

CONCLUSIONS

This work identifies SphK2 as a potential regulator of HCC sexual dimorphism and suggests SphK2 inhibitors now in clinical trials could have opposing, gender-specific effects in patients.

MIRROR: miRNA regulation-level differential network to study sex and ethnic disparities in cancer

Cancer disparities are adverse differences in cancer measures that exist among certain population groups. Given that the role they play not only in the disease prognosis but also in therapy response, there is an urgent need to understand what causes them. Most studies investigate these disparities by analyzing transcriptomic data and in particular miRNAs for their regulatory role, but only focusing on expression levels. To face this challenge we propose MIRROR, a new method which analyzes a differential co-expression network of miRNAs between patients' cohorts, to study the role they play at the target genes' level. Doing so, we can study the altered molecular mechanism that are linked to cancer disparities. The application of MIRROR to two different cases of cancer disparities has demonstrated its efficacy in identifying molecular players involved in the considered disparity, presenting itself as a viable option to approach this challenge.

HDI-STARR-seq: Condition-specific enhancer discovery in mouse liver in vivo

Background

STARR-seq and other massively-parallel reporter assays are widely used to discover functional enhancers in transfected cell models, which can be confounded by plasmid vector-induced type-I interferon immune responses and lack the multicellular environment and endogenous chromatin state of complex mammalian tissues.

Results

Here, we describe HDI-STARR-seq, which combines STARR-seq plasmid library delivery to the liver, by hydrodynamic tail vein injection (HDI), with reporter RNA transcriptional initiation driven by a minimal Albumin promoter, which we show is essential for mouse liver STARR-seq enhancer activity assayed 7 days after HDI. Importantly, little or no vector-induced innate type-I interferon responses were observed. Comparisons of HDI-STARR-seq activity between male and female mouse livers and in livers from males treated with an activating ligand of the transcription factor CAR (Nr1i3) identified many condition-dependent enhancers linked to condition-specific gene expression. Further, thousands of active liver enhancers were identified using a high complexity STARR-seq library comprised of ~ 50,000 genomic regions released by DNase-I digestion of mouse liver nuclei. When compared to stringently inactive library sequences, the active enhancer sequences identified were highly enriched for liver open chromatin regions with activating histone marks (H3K27ac, H3K4me1, H3K4me3), were significantly closer to gene transcriptional start sites, and were significantly depleted of repressive (H3K27me3, H3K9me3) and transcribed region histone marks (H3K36me3).

Conclusions

HDI-STARR-seq offers substantial improvements over current methodologies for large scale, functional profiling of enhancers, including condition-dependent enhancers, in liver tissue in vivo, and can be adapted to characterize enhancer activities in a variety of species and tissues by selecting suitable tissue- and species-specific promoter sequences.

AGR2: The Covert Driver and New Dawn of Hepatobiliary and Pancreatic Cancer Treatment

The anterior gradient protein 2 (AGR2) plays a crucial role in facilitating the formation of protein disulfide bonds within the endoplasmic reticulum (ER). Research suggests that AGR2 can function as an oncogene, with its heightened expression linked to the advancement of hepatobiliary and pancreatic cancers through invasion and metastasis. Notably, AGR2 not only serves as a pro-oncogenic agent but also as a downstream targeting protein, indirectly fostering cancer progression. This comprehensive review delves into the established functions and expression patterns of AGR2, emphasizing its pivotal role in cancer progression, particularly in hepatobiliary and pancreatic malignancies. Furthermore, AGR2 emerges as a potential cancer prognostic marker and a promising target for immunotherapy, offering novel avenues for the treatment of hepatobiliary and pancreatic cancers and enhancing patient outcomes.

HDI-STARR-seq: Condition-specific enhancer discovery in mouse liver in vivo

STARR-seq and other massively-parallel reporter assays are widely used to discover functional enhancers in transfected cell models, which can be confounded by plasmid vector-induced type-I interferon immune responses and lack the multicellular environment and endogenous chromatin state of complex mammalian tissues. Here, we describe HDI-STARR-seq, which combines STARR-seq plasmid library delivery to the liver, by hydrodynamic tail vein injection (HDI), with reporter RNA transcriptional initiation driven by a minimal Albumin promoter, which we show is essential for mouse liver STARR-seq enhancer activity assayed 7 days after HDI. Importantly, little or no vector-induced innate type-I interferon responses were observed. Comparisons of HDI-STARR-seq activity between male and female mouse livers and in livers from males treated with an activating ligand of the transcription factor CAR (Nr1i3) identified many condition-dependent enhancers linked to condition-specific gene expression. Further, thousands of active liver enhancers were identified using a high complexity STARR-seq library comprised of ~50,000 genomic regions released by DNase-I digestion of mouse liver nuclei. When compared to stringently inactive library sequences, the active enhancer sequences identified were highly enriched for liver open chromatin regions with activating histone marks (H3K27ac, H3K4me1, H3K4me3), were significantly closer to gene transcriptional start sites, and were significantly depleted of repressive (H3K27me3, H3K9me3) and transcribed region histone marks (H3K36me3). HDI-STARR-seq offers substantial improvements over current methodologies for large scale, functional profiling of enhancers, including condition-dependent enhancers, in liver tissue in vivo, and can be adapted to characterize enhancer activities in a variety of species and tissues by selecting suitable tissue- and species-specific promoter sequences.

Sex differences in cancer and immunotherapy outcomes: the role of androgen receptor

Across the wide range of clinical conditions, there exists a sex imbalance where biological females are more prone to autoimmune diseases and males to some cancers. These discrepancies are the combinatory consequence of lifestyle and environmental factors such as smoking, alcohol consumption, obesity, and oncogenic viruses, as well as other intrinsic biological traits including sex chromosomes and sex hormones. While the emergence of immuno-oncology (I/O) has revolutionised cancer care, the efficacy across multiple cancers may be limited because of a complex, dynamic interplay between the tumour and its microenvironment (TME). Indeed, sex and gender can also influence the varying effectiveness of I/O. Androgen receptor (AR) plays an important role in tumorigenesis and in shaping the TME. Here, we lay out the epidemiological context of sex disparity in cancer and then review the current literature on how AR signalling contributes to such observation via altered tumour development and immunology. We offer insights into AR-mediated immunosuppressive mechanisms, with the hope of translating preclinical and clinical evidence in gender oncology into improved outcomes in personalised, I/O-based cancer care.

Maternal obesity increases the risk of hepatocellular carcinoma through the transmission of an altered gut microbiome

Background & Aims

Emerging evidence suggests that maternal obesity negatively impacts the health of offspring. Additionally, obesity is a risk factor for hepatocellular carcinoma (HCC). Our study aims to investigate the impact of maternal obesity on the risk for HCC development in offspring and elucidate the underlying transmission mechanisms.

Methods

Female mice were fed either a high-fat diet (HFD) or a normal diet (ND). All offspring received a ND after weaning. We studied liver histology and tumor load in a N-diethylnitrosamine (DEN)-induced HCC mouse model.

Results

Maternal obesity induced a distinguishable shift in gut microbial composition. At 40 weeks, female offspring of HFD-fed mothers (HFD offspring) were more likely to develop steatosis (9.43% vs. 3.09%, p = 0.0023) and fibrosis (3.75% vs. 2.70%, p = 0.039), as well as exhibiting an increased number of inflammatory infiltrates (4.8 vs. 1.0, p = 0.018) and higher expression of genes involved in fibrosis and inflammation, compared to offspring of ND-fed mothers (ND offspring). A higher proportion of HFD offspring developed liver tumors after DEN induction (79.8% vs. 37.5%, p = 0.0084) with a higher mean tumor volume (234 vs. 3 μm3, p = 0.0041). HFD offspring had a significantly less diverse microbiota than ND offspring (Shannon index 2.56 vs. 2.92, p = 0.0089), which was rescued through co-housing. In the principal component analysis, the microbiota profile of co-housed animals clustered together, regardless of maternal diet. Co-housing of HFD offspring with ND offspring normalized their tumor load.

Conclusions

Maternal obesity increases female offspring's susceptibility to HCC. The transmission of an altered gut microbiome plays an important role in this predisposition.

Impact and implications

The worldwide incidence of obesity is constantly rising, with more and more children born to obese mothers. In this study, we investigate the impact of maternal diet on gut microbiome composition and its role in liver cancer development in offspring. We found that mice born to mothers with a high-fat diet inherited a less diverse gut microbiome, presented chronic liver injury and an increased risk of developing liver cancer. Co-housing offspring from normal diet- and high-fat diet-fed mothers restored the gut microbiome and, remarkably, normalized the risk of developing liver cancer. The implementation of microbial screening and restoration of microbial diversity holds promise in helping to identify and treat individuals at risk to prevent harm for future generations.

FOXA1 and FOXA2: the regulatory mechanisms and therapeutic implications in cancer

FOXA1 (Forkhead Box A1) and FOXA2 (Forkhead Box A2) serve as pioneering transcription factors that build gene expression capacity and play a central role in biological processes, including organogenesis and differentiation, glycolipid metabolism, proliferation, migration and invasion, and drug resistance. Notably, FOXA1 and FOXA2 may exert antagonistic, synergistic, or complementary effects in the aforementioned biological processes. This article focuses on the molecular mechanisms and clinical relevance of FOXA1 and FOXA2 in steroid hormone-induced malignancies and highlights potential strategies for targeting FOXA1 and FOXA2 for cancer therapy. Furthermore, the article describes the prospect of targeting upstream regulators of FOXA1/FOXA2 to regulate its expression for cancer therapy because of the drug untargetability of FOXA1/FOXA2.

NatD epigenetically activates FOXA2 expression to promote breast cancer progression by facilitating MMP14 expression

N-α-acetyltransferase D (NatD) mediates N-α-terminal acetylation of histone H4 (Nt-Ac-H4), but its role in breast cancer metastasis remains unknown. Here, we show that depletion of NatD directly represses the expression of FOXA2, and is accompanied by a significant reduction in Nt-Ac-H4 enrichment at the FOXA2 promoter. We show that NatD is commonly upregulated in primary breast cancer tissues, where its expression level correlates with FOXA2 expression, enhanced invasiveness, and poor clinical outcomes. Furthermore, we show that FOXA2 promotes the migration and invasion of breast cancer cells by activating MMP14 expression. MMP14 is also upregulated in breast cancer tissues, where its expression level correlates with FOXA2 expression and poor clinical prognosis. Our study shows that the NatD-FOXA2-MMP14 axis functions as a key signaling pathway to promote the migratory and invasive capabilities of breast cancer cells, suggesting that NatD is a critical epigenetic modulator of cell invasion during breast cancer progression.

Current Perspectives on the Molecular and Clinical Relationships between Primary Biliary Cholangitis and Hepatocellular Carcinoma

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterised by the immune-mediated destruction of small and medium intrahepatic bile ducts, with variable outcomes and progression. This review summarises the state of the art regarding the risk of neoplastic progression in PBC patients, with a particular focus on the molecular alterations present in PBC and in hepatocellular carcinoma (HCC), which is the most frequent liver cancer in these patients. Major risk factors are male gender, viral infections, e.g., HBV and HCV, non-response to UDCA, and high alcohol intake, as well as some metabolic-associated factors. Overall, HCC development is significantly more frequent in patients with advanced histological stages, being related to liver cirrhosis. It seems to be of fundamental importance to unravel eventual dysfunctional molecular pathways in PBC patients that may be used as biomarkers for HCC development. In the near future, this will possibly take advantage of artificial intelligence-designed algorithms.

Atypical inflammatory kinase IKBKE phosphorylates and inactivates FoxA1 to promote liver tumorigenesis

Physiologically, FoxA1 plays a key role in liver differentiation and development, and pathologically exhibits an oncogenic role in prostate and breast cancers. However, its role and upstream regulation in liver tumorigenesis remain unclear. Here, we demonstrate that FoxA1 acts as a tumor suppressor in liver cancer. Using a CRISPR-based kinome screening approach, noncanonical inflammatory kinase IKBKE has been identified to inhibit FoxA1 transcriptional activity. Notably, IKBKE directly binds to and phosphorylates FoxA1 to reduce its complex formation and DNA interaction, leading to elevated hepatocellular malignancies. Nonphosphorylated mimic Foxa1 knock-in mice markedly delay liver tumorigenesis in hydrodynamic transfection murine models, while phospho-mimic Foxa1 knock-in phenocopy Foxa1 knockout mice to exhibit developmental defects and liver inflammation. Notably, Ikbke knockout delays diethylnitrosamine (DEN)-induced mouse liver tumor development. Together, our findings not only reveal FoxA1 as a bona fide substrate and negative nuclear effector of IKBKE in hepatocellular carcinioma (HCC) but also provide a promising strategy to target IKBEK for HCC therapy.

Pharmacological activation of constitutive androstane receptor induces female-specific modulation of hepatic metabolism

Background & Aims

The constitutive androstane receptor (CAR) is a nuclear receptor that binds diverse xenobiotics and whose activation leads to the modulation of the expression of target genes involved in xenobiotic detoxification and energy metabolism. Although CAR hepatic activity is considered to be higher in women than in men, its sex-dependent response to an acute pharmacological activation has seldom been investigated.

Methods

The hepatic transcriptome, plasma markers, and hepatic metabolome, were analysed in Car+/+ and Car-/- male and female mice treated either with the CAR-specific agonist 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene (TCPOBOP) or with vehicle.

Results

Although 90% of TCPOBOP-sensitive genes were modulated in a sex-independent manner, the remaining 10% showed almost exclusive female liver specificity. These female-specific CAR-sensitive genes were mainly involved in xenobiotic metabolism, inflammation, and extracellular matrix organisation. CAR activation also induced higher hepatic oxidative stress and hepatocyte cytolysis in females than in males. Hepatic expression of flavin monooxygenase 3 (Fmo3) was almost abolished and was associated with a decrease in hepatic trimethylamine-N-oxide (TMAO) concentration in TCPOBOP-treated females. In line with a potential role in the control of TMAO homeostasis, CAR activation decreased platelet hyper-responsiveness in female mice supplemented with dietary choline.

Conclusions

More than 10% of CAR-sensitive genes are sex-specific and influence hepatic and systemic responses such as platelet aggregation. CAR activation may be an important mechanism of sexually-dimorphic drug-induced liver injury.

Impact and implications

CAR is activated by many drugs and pollutants. Its pharmacological activation had a stronger impact on hepatic gene expression and metabolism in females than in males, and had a specific impact on liver toxicity and trimethylamine metabolism. Sexual dimorphism should be considered when testing and/or prescribing xenobiotics known to activate CAR.

The urothelial gene regulatory network: understanding biology to improve bladder cancer management

The urothelium is a stratified epithelium composed of basal cells, one or more layers of intermediate cells, and an upper layer of differentiated umbrella cells. Most bladder cancers (BLCA) are urothelial carcinomas. Loss of urothelial lineage fidelity results in altered differentiation, highlighted by the taxonomic classification into basal and luminal tumors. There is a need to better understand the urothelial transcriptional networks. To systematically identify transcription factors (TFs) relevant for urothelial identity, we defined highly expressed TFs in normal human bladder using RNA-Seq data and inferred their genomic binding using ATAC-Seq data. To focus on epithelial TFs, we analyzed RNA-Seq data from patient-derived organoids recapitulating features of basal/luminal tumors. We classified TFs as "luminal-enriched", "basal-enriched" or "common" according to expression in organoids. We validated our classification by differential gene expression analysis in Luminal Papillary vs. Basal/Squamous tumors. Genomic analyses revealed well-known TFs associated with luminal (e.g., PPARG, GATA3, FOXA1) and basal (e.g., TP63, TFAP2) phenotypes and novel candidates to play a role in urothelial differentiation or BLCA (e.g., MECOM, TBX3). We also identified TF families (e.g., KLFs, AP1, circadian clock, sex hormone receptors) for which there is suggestive evidence of their involvement in urothelial differentiation and/or BLCA. Genomic alterations in these TFs are associated with BLCA. We uncover a TF network involved in urothelial cell identity and BLCA. We identify novel candidate TFs involved in differentiation and cancer that provide opportunities for a better understanding of the underlying biology and therapeutic intervention.

A Mammalian Conserved Circular RNA CircLARP1B Regulates Hepatocellular Carcinoma Metastasis and Lipid Metabolism

Circular RNAs (circRNAs) have emerged as crucial regulators in physiology and human diseases. However, evolutionarily conserved circRNAs with potent functions in cancers are rarely reported. In this study, a mammalian conserved circRNA circLARP1B is identified to play critical roles in hepatocellular carcinoma (HCC). Patients with high circLARP1B levels have advanced prognostic stage and poor overall survival. CircLARP1B facilitates cellular metastatic properties and lipid accumulation through promoting fatty acid synthesis in HCC. CircLARP1B deficient mice exhibit reduced metastasis and less lipid accumulation in an induced HCC model. Multiple lines of evidence demonstrate that circLARP1B binds to heterogeneous nuclear ribonucleoprotein D (HNRNPD) in the cytoplasm, and thus affects the binding of HNRNPD to sensitive transcripts including liver kinase B1 (LKB1) mRNA. This regulation causes decreased LKB1 mRNA stability and lower LKB1 protein levels. Antisense oligodeoxynucleotide complementary to theHNRNPD binding sites in circLARP1B increases the HNRNPD binding to LKB1 mRNA. Through the HNRNPD-LKB1-AMPK pathway, circLARP1B promotes HCC metastasis and lipid accumulation. Results from AAV8-mediated hepatocyte-directed knockdown of circLARP1B or Lkb1 in mouse models also demonstrate critical roles of hepatocytic circLARP1B regulatory pathway in HCC metastasis and lipid accumulation, and indicate that circLARP1B may be potential target of HCC treatment.

Sex difference in liver diseases: How preclinical models help to dissect the sex-related mechanisms sustaining NAFLD and hepatocellular carcinoma

Only a few preclinical findings are confirmed in the clinic, posing a critical issue for clinical development. Therefore, identifying the best preclinical models can help to dissect molecular and mechanistic insights into liver disease pathogenesis while being clinically relevant. In this context, the sex relevance of most preclinical models has been only partially considered. This is particularly significant in NAFLD and HCC, which have a higher prevalence in men when compared to pre-menopause women but not to those in post-menopausal status, suggesting a role for sex hormones in the pathogenesis of the diseases. This review gathers the sex-relevant findings and the available preclinical models focusing on both in vitro and in vivo studies and discusses the potential implications and perspectives of introducing the sex effect in the selection of the best preclinical model. This is a critical aspect that would help to tailor personalized therapies based on sex.

Plasma growth hormone pulses induce male-biased pulsatile chromatin opening and epigenetic regulation in adult mouse liver

Sex differences in plasma growth hormone (GH) profiles, pulsatile in males and persistent in females, regulate sex differences in hepatic STAT5 activation linked to sex differences in gene expression and liver disease susceptibility, but little is understood about the fundamental underlying, GH pattern-dependent regulatory mechanisms. Here, DNase-I hypersensitivity site (DHS) analysis of liver chromatin accessibility in a cohort of 18 individual male mice established that the endogenous male rhythm of plasma GH pulse-stimulated liver STAT5 activation induces dynamic, repeated cycles of chromatin opening and closing at several thousand liver DHS and comprises a novel mechanism conferring male bias to liver chromatin accessibility. Strikingly, a single physiological replacement dose of GH given to hypophysectomized male mice restored, within 30 min, liver STAT5 activity and chromatin accessibility at 83% of the dynamic, pituitary hormone-dependent male-biased DHS. Sex-dependent transcription factor binding patterns and chromatin state analysis identified key genomic and epigenetic features distinguishing this dynamic, STAT5-driven mechanism of male-biased chromatin opening from a second GH-dependent mechanism operative at static male-biased DHS, which are constitutively open in male liver. Dynamic but not static male-biased DHS adopt a bivalent-like epigenetic state in female liver, as do static female-biased DHS in male liver, albeit using distinct repressive histone marks in each sex, namely, H3K9me3 at male-biased DHS in female liver and H3K27me3 at female-biased DHS in male liver. Moreover, sex-biased H3K36me3 marks are uniquely enriched at static sex-biased DHS, which may serve to keep these sex-dependent hepatocyte enhancers free of H3K27me3 repressive marks and thus constitutively open. Pulsatile chromatin opening stimulated by endogenous, physiological hormone pulses is thus one of two distinct GH-determined mechanisms for establishing widespread sex differences in hepatic chromatin accessibility and epigenetic regulation, both closely linked to sex-biased gene transcription and the sexual dimorphism of liver function.

The role of sex hormones and receptors in HBV infection and development of HBV-related HCC

Gender disparity in hepatitis B virus (HBV)-related diseases has been extensively documented. Epidemiological studies consistently reported that males have a higher prevalence of HBV infection and incidence of hepatocellular carcinoma (HCC). Further investigations have revealed that sex hormone-related signal transductions play a significant role in gender disparity. Sex hormone axes showed significantly different responses to virus entry and replication. The sex hormones axes change the HBV-specific immune responses and antitumor immunity. Additionally, Sex hormone axes showed different effects on the development of HBV-related disease. But the role of sex hormones remains controversial, and researchers have not reached a consensus on the role of sex hormones and the use of hormone therapies in HCC treatment. In this review, we aim to summarize the experimental findings on sex hormones and provide a comprehensive understanding of their roles in the development of HCC and their implications for hormone-related HCC treatment.

Plasma Growth Hormone Pulses Induce Male-biased Pulsatile Chromatin Opening and Epigenetic Regulation in Adult Mouse Liver

Sex-differences in plasma growth hormone (GH) profiles, pulsatile in males and persistent in females, regulate sex differences in hepatic STAT5 activation linked to sex differences in gene expression and liver disease susceptibility, but little is understood about the fundamental underlying, GH pattern-dependent regulatory mechanisms. Here, DNase hypersensitivity site (DHS) analysis of liver chromatin accessibility in a cohort of 18 individual male mice established that the endogenous male rhythm of plasma GH pulse-stimulated liver STAT5 activation induces dynamic, repeated cycles of chromatin opening and closing at several thousand liver DHS and comprises a novel mechanism conferring male bias to liver chromatin accessibility. Strikingly, a single physiological replacement dose of GH given to hypophysectomized male mice restored, within 30 min, liver STAT5 activity and chromatin accessibility at 83% of the pituitary hormone-dependent dynamic male-biased DHS. Sex-dependent transcription factor binding patterns and chromatin state analysis identified key genomic and epigenetic features distinguishing this dynamic, STAT5-driven mechanism of male-biased chromatin opening from a second GH-dependent mechanism operative at static male-biased DHS, which are constitutively open in male liver. Dynamic but not static male-biased DHS adopt a bivalent-like epigenetic state in female liver, as do static female-biased DHS in male liver, albeit using distinct repressive histone marks in each sex, namely, H3K27me3 at female-biased DHS in male liver, and H3K9me3 at male-biased DHS in female liver. Moreover, sex-biased H3K36me3 marks are uniquely enriched at static sex-biased DHS, which may serve to keep these sex-dependent hepatocyte enhancers free of H3K27me3 repressive marks and thus constitutively open. Pulsatile chromatin opening stimulated by endogenous, physiological hormone pulses is thus one of two distinct GH-determined mechanisms for establishing widespread sex differences in hepatic chromatin accessibility and epigenetic regulation, both closely linked to sex-biased gene transcription and the sexual dimorphism of liver function.

Sex-biased gene expression across mammalian organ development and evolution

Sexually dimorphic traits are common among mammals and are specified during development through the deployment of sex-specific genetic programs. Because little is known about these programs, we investigated them using a resource of gene expression profiles in males and females throughout the development of five organs in five mammals (human, mouse, rat, rabbit, and opossum) and a bird (chicken). We found that sex-biased gene expression varied considerably across organs and species and was often cell-type specific. Sex differences increased abruptly around sexual maturity instead of increasing gradually during organ development. Finally, sex-biased gene expression evolved rapidly at the gene level, with differences between organs in the evolutionary mechanisms used, but more slowly at the cellular level, with the same cell types being sexually dimorphic across species.

Hyperpolarization-activated cyclic nucleotide-gated cation channel 3 promotes HCC development in a female-biased manner

Sex differences in hepatocellular carcinoma (HCC) development are regulated by sex and non-sex chromosomes, sex hormones, and environmental factors. We previously reported that Ncoa5+/- mice develop HCC in a male-biased manner. Here we show that NCOA5 expression is reduced in male patient HCCs while the expression of an NCOA5-interacting tumor suppressor, TIP30, is lower in female HCCs. Tip30 heterozygous deletion does not change HCC incidence in Ncoa5+/- male mice but dramatically increases HCC incidence in Ncoa5+/- female mice, accompanied by hepatic hyperpolarization-activated cyclic nucleotide-gated cation channel 3 (HCN3) overexpression. HCN3 overexpression cooperates with MYC to promote mouse HCC development, whereas Hcn3 knockout preferentially hinders HCC development in female mice. Furthermore, HCN3 amplification and overexpression occur in human HCCs and correlate with a poorer prognosis of patients in a female-biased manner. Our results suggest that TIP30 and NCOA5 protect against female liver oncogenesis and that HCN3 is a female-biased HCC driver.

Regulation of the somatotropic axis by MYC-mediated miRNA repression

The transcription factor MYC is overexpressed in many human cancers and has a significant causal role in tumor incidence and progression. In contrast, Myc +/- heterozygous mice, which have decreased MYC expression, exhibit a 10-20% increase in lifespan and a decreased incidence or progression of several age-related diseases. Myc heterozygous mice were also reported to have decreased mTOR and IGF1 signaling, two pathways whose reduced activity is associated with longevity in diverse species. Given MYC's downstream role in these pathways, the downregulation of mTOR and IGF1 signaling in Myc heterozygotes suggests the presence of feedback loops within this regulatory network. In this communication we provide further evidence that the reduction of Myc expression in Myc +/- heterozygous mice provokes a female-specific decrease in circulating IGF1 as well as a reduction of IGF1 protein in the liver. In particular, reduced Myc expression led to upregulation of miRNAs that target the Igf1 transcript, thereby inhibiting its translation and leading to decreased IGF1 protein levels. Using Argonaute (AGO)-CLIP-sequencing we found enrichment of AGO binding in the Igf1 transcript at the target sites of let-7, miR-122, and miR-29 in female, but not male Myc heterozygotes. Upregulation of the liver-specific miR-122 in primary hepatocytes in culture and in vivo in mice resulted in significant downregulation of IGF1 protein, but not mRNA. Reduced levels of IGF1 increased GH production in the pituitary through a well-documented negative-feedback relationship. In line with this, we found that IGF1 levels in bone (where miR-122 is not expressed) were unchanged, consistent with the decreased incidence of osteoporosis in female Myc heterozygotes, despite decreased circulating IGF1.

Hepatocyte-specific HDAC3 ablation promotes hepatocellular carcinoma in females by suppressing Foxa1/2

BACKGROUND

Hepatocellular carcinoma (HCC), the most common primary liver cancer, prevails mainly in males and has long been attributed to androgens and higher circumstantial levels of interleukin-6 (IL-6) produced by resident hepatic macrophages.

METHODS

Constitutively hepatocyte-specific histone deacetylase 3 (HDAC3)-deficient (HDAC3LCKO) mice and constitutively hepatocyte-specific HDAC3 knockout and systemic IL-6 simultaneously ablated (HDAC3LCKO& IL-6-/-) mice were used in our study to explore the causes of sex differences in HCC. Additionally, we performed human HCC tissues with an IHC score. Correlation analysis and linear regression plots were constructed to reveal the association between HDAC3 and its candidate genes. To further elucidate that HDAC3 controls the expression of Foxa1/2, we knocked down HDAC3 in HUH7 liver cancer cells.

RESULTS

We observed a contrary sex disparity, with an earlier onset and higher incidence of HCC in female mice when HDAC3 was selectively ablated in the liver. Loss of HDAC3 led to constant liver injury and the spontaneous development of HCC. Unlike the significant elevation of IL-6 in male mice at a very early age, female mice exhibit stable IL-6 levels, and IL-6 ablation did not eliminate the sex disparity in hepatocarcinogenesis in HDAC3-deficient mice. Oestrogen often protects the liver when combined with oestrogen receptor alpha (ERα); however, ovariectomy in HDAC3-ablated female mice significantly delayed tumourigenesis. The oestrogen-ERα axis can also play a role in tumour promotion in the absence of Foxa1 and Foxa2 in the receptor complex. Loss of HDAC3 profoundly reduced the expression of both Foxa1 and Foxa2 and impaired the binding between Foxa1/2 and ERα. Furthermore, a more frequent HDAC3 decrease accompanied by the simultaneous Foxa1/2 decline was found in female HCC compared to that in male HCC.

CONCLUSION

In summary, we reported that loss of HDAC3 reduces Foxa1/2 and thus promotes HCC development in females in an oestrogen-dependent manner.

Transposon delivery for CRISPR-based loss-of-function screen in mice identifies NF2 as a cooperating gene involved with the canonical WNT signaling molecular class of hepatocellular carcinoma

Various molecular subclasses of hepatocellular carcinoma (HCC) exists, with many novel cooperating oncogenes and tumor suppressor genes involved in its tumorigenesis. The emerging importance of WNT signaling in HCC has been established. However, the intricate genetic mechanisms involved in this complex signaling pathway remains to be elucidated. Importantly, while some cooperating genes have been identified, there are still many unknown genes associated with catenin beta 1 (CTNNB1)-induced HCC. Mutations in both oncogenes and tumor suppressor genes are required for HCC tumorigenesis. The emergence of the CRISPR/Cas9 system has allowed researchers now to target both alleles efficiently. In this novel study, the Sleeping Beauty transposon system was used as a gene delivery system in vivo to stably integrate an expression cassette that carry pools of gRNAs and overexpress a mutant version of CTNNB1 into the hepatocyte genome. We identified 206 candidate genes that drive HCC tumorigenesis in the context of WNT signaling activation and, neurofibromin 2 (NF2) gene, a known tumor suppressor gene with clinical relevance was validated in this proof-of-principle study.

Dihydroartemisinin increased the abundance of Akkermansia muciniphila by YAP1 depression that sensitizes hepatocellular carcinoma to anti-PD-1 immunotherapy

The effect of anti-programmed cell death 1 (anti-PD-1) immunotherapy is limited in patients with hepatocellular carcinoma (HCC). Yes-associated protein 1 (YAP1) expression increased in liver tumor cells in early HCC, and Akkermansia muciniphila abundance decreased in the colon. The response to anti-PD-1 treatment is associated with A. muciniphila abundance in many tumors. However, the interaction between A. muciniphila abundance and YAP1 expression remains unclear in HCC. Here, anti-PD-1 treatment decreased A. muciniphila abundance in the colon, but increased YAP1 expression in the tumor cells by mice with liver tumors in situ. Mechanistically, hepatocyte-specific Yap1 knockout (Yap1LKO) maintained bile acid homeostasis in the liver, resulting in an increased abundance of A. muciniphila in the colon. Yap1 knockout enhanced anti-PD-1 efficacy. Therefore, YAP1 inhibition is a potential target for increasing A. muciniphila abundance to promote anti-PD-1 efficacy in liver tumors. Dihydroartemisinin (DHA), acting as YAP1 inhibitor, increased A. muciniphila abundance to sensitize anti-PD-1 therapy. A. muciniphila by gavage increased the number and activation of CD8+ T cells in liver tumor niches during DHA treatment or combination with anti-PD-1. Our findings suggested that the combination anti-PD-1 with DHA is an effective strategy for liver tumor treatment.

Elevated FBXW10 drives hepatocellular carcinoma tumorigenesis via AR-VRK2 phosphorylation-dependent GAPDH ubiquitination in male transgenic mice

Hepatocellular carcinoma (HCC), the most common liver cancer, occurs mainly in men, but the underlying mechanism remains to be further explored. Here, we report that ubiquitinated glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is responsible for HCC tumorigenesis in males. Mechanistically, FBXW10 promotes GAPDH polyubiquitination and activation; VRK2-dependent phosphorylation of GAPDH Ser151 residue is critical for GAPDH ubiquitination and activation. Activated GAPDH interacts with TRAF2, leading to upregulation of the canonical and noncanonical NF-κB pathways, and increases PD-L1 and AR-VRK2 expression, followed by induction of immune evasion, HCC tumorigenesis, and metastasis. Notably, the GAPDH inhibitor koningic acid (KA) activates immune response and protects against FBXW10-driven HCC in vivo. In HCC clinical samples, the expression of active GAPDH is positively correlated with that of FBXW10 and VRK2. We propose that the FBXW10/AR/VRK2/GAPDH/NF-κB axis is critical for HCC tumorigenesis in males. Targeting this axis with KA is a potential therapeutic strategy for male HCC patients.

Gender Differences in the Pathogenesis and Risk Factors of Hepatocellular Carcinoma

Several chronic liver diseases are characterized by a clear gender disparity. Among them, hepatocellular carcinoma (HCC) shows significantly higher incidence rates in men than in women. The different epidemiological distribution of risk factors for liver disease and HCC only partially accounts for these gender differences. In fact, the liver is an organ with recognized sexual dysmorphism and is extremely sensitive to the action of androgens and estrogens. Sex hormones act by modulating the risk of developing HCC and influencing its aggressiveness, response to treatments, and prognosis. Furthermore, androgens and estrogens are able to modulate the action of other factors and cofactors of liver damage (e.g., chronic HBV infection, obesity), significantly influencing their carcinogenic power. The purpose of this review is to examine the factors related to the different gender distribution in the incidence of HCC as well as the pathophysiological mechanisms involved, with particular reference to the central role played by sex hormones.

Role of exosomes in the development of the immune microenvironment in hepatocellular carcinoma

Despite numerous improved treatment methods used in recent years, hepatocellular carcinoma (HCC) is still a disease with a high mortality rate. Many recent studies have shown that immunotherapy has great potential for cancer treatment. Exosomes play a significant role in negatively regulating the immune system in HCC. Understanding how these exosomes play a role in innate and adaptive immunity in HCC can significantly improve the immunotherapeutic effects on HCC. Further, engineered exosomes can deliver different drugs and RNA molecules to regulate the immune microenvironment of HCC by regulating the aforementioned immune pathway, thereby significantly improving the mortality rate of HCC. This study aimed to declare the role of exosomes in the development of the immune microenvironment in HCC and list engineered exosomes that could be used for clinical transformation therapy. These findings might be beneficial for clinical patients.

ERα prevents tumorigenesis of both liver and breast cancer cells through CCN5

Estrogen receptor alpha (ERα)-mediated estrogen signaling has also shown to prevent hepatic tumorigenesis in mice. Consistent with this, hormone replacement therapy with estrogen supplementation dramatically reduced the risk of hepatocellular carcinoma. Silencing of ERα is also a key event for the transformation of ERα-positive breast cancer cells into malignant triple-negative breast cancer cells. However, the mechanisms underlying ERα-mediated prevention of both hepatic and mammary tumorigenesis in humans are still unclear. Here, we present a functional genomics study of ERα targeting by comparing human liver cancer cells with human breast cancer cells using "loss or gain of function" genetic assays of ERα in vitro and in vivo. We discover that cellular communication network factor 5 (CCN5) is a direct downstream target of ERα; ERα suppresses growth and prevents tumorigenesis and malignant transformation of both liver and breast cancer cells through CCN5 in humans. The ERα-CCN5 regulatory axis functions as suppressors for both hepatic and mammary tumors, which is a common mechanism of preventing tumorigenesis for both liver cancer and breast cancer in humans.

Dihydroartemisinin inhibited interleukin-18 expression by decreasing YAP1 in hepatocellular carcinoma cells

BACKGROUND

Yes-associated protein 1 (YAP1) is highly expressed in liver cancer and has been used as an independent prognostic marker for hepatocellular carcinoma (HCC), while inhibition of YAP1 slows down the progression of HCC. Interleukin-18 (IL-18) also tends to be highly expressed in liver cancer. Previous research has proved that dihydroartemisinin (DHA) plays an important role in HCC treatment by reducing YAP1 expression. However, the relationship between YAP1 and IL-18 has not been reported in HCC, especially during DHA therapy.

OBJECTIVE

The purpose of this study was to clarify the relationship between YAP1 and IL-18 in HCC cells, and to explicit the role of IL-18 in the treatment of HCC by DHA.

METHODS AND RESULTS

We found that YAP1 and IL-18 were highly expressed in patients with hepatocellular carcinoma by bioinformatics analysis. Moreover, YAP1 was positively correlated with IL18 in liver cancer. YAP1 and IL18 correlated with immune cell infiltration, notably T cell exhaustion. YAP1 knockdown decreased IL-18 expression, while YAP1 overexpression increased the IL-18 expression in HCC cells. DHA reduced IL-18 expression through YAP1 in HCC cells. Further, DHA reduced the growth of Hepa1-6 cells subcutaneous xenograft tumors by inhibiting the expression of YAP1 and IL-18. However, DHA improved IL-18 in serum and adjacent tissues from DEN/TCPOBOP-induced liver tumor model in C57BL/6 mice.

CONCLUSION

YAP1 was positively correlated with IL-18 in HCC. DHA reduced the expression of IL-18 by inhibiting YAP1 and plays a role in the treatment of HCC. Our study suggested that IL-18 is a potential target for the treatment of HCC, and DHA is a promising drug for HCC therapy.

DATA AVAILABILITY

The dataset that supports the findings of this study is available from the corresponding author upon reasonable request.

Stranger Things: New Roles and Opportunities for Androgen Receptor in Oncology Beyond Prostate Cancer

The androgen receptor (AR) is one of the oldest therapeutic targets in oncology and continues to dominate the treatment landscape for advanced prostate cancer, where nearly all treatment regimens include some form of AR modulation. In this regard, AR remains the central driver of prostate cancer cell biology. Emerging preclinical and clinical data implicate key roles for AR in additional cancer types, thereby expanding the importance of this drug target beyond prostate cancer. In this mini-review, new roles for AR in other cancer types are discussed as well as their potential for treatment with AR-targeted agents. Our understanding of these additional functions for AR in oncology expand this receptor's potential as a therapeutic target and will help guide the development of new treatment approaches.

Multi-omics profiling of cholangiocytes reveals sex-specific chromatin state dynamics during hepatic cystogenesis in polycystic liver disease

BACKGROUND & AIMS

Cholangiocytes transit from quiescence to hyperproliferation during cystogenesis in polycystic liver disease (PLD), the severity of which displays prominent sex differences. Epigenetic regulation plays important roles in cell state transition. We aimed to investigate the sex-specific epigenetic basis of hepatic cystogenesis and to develop therapeutic strategies targeting epigenetic modifications for PLD treatment.

METHODS

Normal and cystic primary cholangiocytes were isolated from wild-type and PLD mice of both sexes. Chromatin states were characterized by analyzing chromatin accessibility (ATAC sequencing) and multiple histone modifications (chromatin immunoprecipitation sequencing). Differential gene expression was determined by transcriptomic analysis (RNA sequencing). Pharmacologic inhibition of epigenetic modifying enzymes was undertaken in PLD model mice.

RESULTS

Through genome-wide profiling of chromatin dynamics, we revealed a profound increase of global chromatin accessibility during cystogenesis in both male and female PLD cholangiocytes. We identified a switch from H3K9me3 to H3K9ac on cis-regulatory DNA elements of cyst-associated genes and showed that inhibition of H3K9ac acetyltransferase or H3K9me3 demethylase slowed cyst growth in male, but not female, PLD mice. In contrast, we found that H3K27ac was specifically increased in female PLD mice and that genes associated with H3K27ac-gained regions were enriched for cyst-related pathways. In an integrated epigenomic and transcriptomic analysis, we identified an estrogen receptor alpha-centered transcription factor network associated with the H3K27ac-regulated cystogenic gene expression program in female PLD mice.

CONCLUSIONS

Our findings highlight the multi-layered sex-specific epigenetic dynamics underlying cholangiocyte state transition and reveal a potential epigenetic therapeutic strategy for male PLD patients.

IMPACT AND IMPLICATIONS

In the present study, we elucidate a sex-specific epigenetic mechanism underlying the cholangiocyte state transition during hepatic cystogenesis and identify epigenetic drugs that effectively slow cyst growth in male PLD mice. These findings underscore the importance of sex difference in the pathogenesis of PLD and may guide researchers and physicians to develop sex-specific personalized approaches for PLD treatment.

Upregulation of FOXA2 in uterine luminal epithelium and vaginal basal epithelium of epiERα-/- (Esr1fl/flWnt7aCre/+) mice†

Forkhead box protein A2 (FOXA2) is a pioneer transcription factor important for epithelial budding and morphogenesis in different organs. It has been used as a specific marker for uterine glandular epithelial cells (GE). FOXA2 has close interactions with estrogen receptor α (ERα). ERα binding to Foxa2 gene in the uterus indicates its regulation of Foxa2. The intimate interactions between ERα and FOXA2 and their essential roles in early pregnancy led us to investigate the expression of FOXA2 in the female reproductive tract of pre-implantation epiERα-/- (Esr1fl/flWnt7aCre/+) mice, in which ERα is conditionally deleted in the epithelium of reproductive tract. In the oviduct, FOXA2 is detected in the ciliated epithelial cells of ampulla but absent in the isthmus of day 3.5 post-coitum (D3.5) Esr1fl/fl control and epiERα-/- mice. In the uterus, FOXA2 expression in the GE appears to be comparable between Esr1fl/fl and epiERα-/- mice. However, FOXA2 is upregulated in the D0.5 and D3.5 but not PND25-28 epiERα-/- uterine luminal epithelial cells (LE). In the vagina, FOXA2 expression is low in the basal layer and increases toward the superficial layer of the D3.5 Esr1fl/fl vaginal epithelium, but FOXA2 is detected in the basal, intermediate, and superficial layers, with the strongest FOXA2 expression in the intermediate layers of the D3.5 epiERα-/- vaginal epithelium. This study demonstrates that loss of ERα in LE and vaginal basal layer upregulates FOXA2 expression in these epithelial cells during early pregnancy. The mechanisms for epithelial cell-type specific regulation of FOXA2 by ERα remain to be elucidated.

A Selective Androgen Receptor Modulator, S4, Displays Robust Anti-cancer Activity on Hepatocellular Cancer Cells by Negatively Regulating PI3K/AKT/mTOR Signaling Pathway

Hepatocellular carcinoma (HCC) is a major global health problem that often correlates with poor prognosis. Due to the insufficient therapy options with limited benefits, it is crucial to identify new therapeutic approaches to overcome HCC. One of the vital signaling pathways in organ homeostasis and male sexual development is Androgen Receptor (AR) signaling. Its activity affects several genes that contribute to cancer characteristics and have essential roles in cell cycle progression, proliferation, angiogenesis, and metastasis. AR signaling has been shown to be misregulated in many cancers, including HCC, suggesting that it might contribute to hepatocarcinogenesis. Targeting AR signaling using anti-androgens, AR inhibitors, or AR-degrading molecules is a powerful and promising strategy to defeat HCC. In this study, AR signaling was targeted by a novel Selective Androgen Receptor Modulator (SARM), S4, in HCC cells to evaluate its potential anti-cancer effect. To date, S4 activity in cancer has not been demonstrated, and our data unrevealed that S4 significantly impaired HCC growth, migration, proliferation, and induced apoptosis through inhibiting PI3K/AKT/mTOR signaling. Since PI3K/AKT/mTOR signaling is frequently activated in HCC and contributes to its aggressiveness and poor prognosis, its negative regulation by the downregulation of critical components via S4 was a prominent finding. Further studies are necessary to investigate the S4 action mechanism and anti-tumorigenic capacity in in-vivo.

Sex steroid axes in determining male predominance in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death. The mechanisms for male propensity in HCC incidence, prognosis and treatment responses are complicated and remain inconclusive. Sex-biased molecular signatures in carcinogenesis, viral infections and immune responses have been studied predominantly within the context of sex hormones effects. This review integrates current knowledge on the mechanisms through which the hormones regulate HCC development in sexually dimorphic fashion. Firstly, the androgen/androgen receptor (AR) accelerate cell proliferation and virus infection, especially during the initial stage of HCC, while estrogen/estrogen receptor (ER) function in an opposite way to induce cell apoptosis and immune responses. Interestingly, the controversial effects of AR in late stage of HCC metastasis are summarized and the reasons are attributed to inconsistent cancer grading or experimental models between the studies. In addition, the new insights into these intricate cellular and molecular mechanisms underlying sexual dimorphism are fully discussed. A detailed understanding of sex hormones-associated regulation to male predominance in HCC may help to develop personalized therapeutic strategies in high-risk populations.

Targeted metabolomics analysis identified the role of FOXA1 in the change in glutamate-glutamine metabolic pattern of BaP malignantly transformed 16HBE cells

The carcinogenic mechanism of benzo[a]pyrene (BaP) is far from being elucidated. FOXA1 has been confirmed to play an oncogenic role in BaP-transformed cell THBEc1. To explore the changes in amino acid metabolic patterns, especially glutamate-glutamine (Glu-Gln) metabolic pattern caused by BaP-induced transformation and the possible role FOXA1 might play in it, we compared amino acid metabolic characteristics between THBEc1 cells and control 16HBE cells using a targeted metabolomics method and determined the effects of FOXA1 knockout on the amino acid metabolic pattern using FOXA1 knockout cell THBEc1-ΔFOXA1-c34. The amino acid metabolic patterns of THBEc1 and 16HBE cells were different, which was manifested by the differential consumption of 18 amino acids and the difference in the intracellular content of 21 amino acids. The consumption and intracellular content of Glu and Gln are different between the two types of cells, accompanied by upregulation of FOXA1, GLUL, SLC1A3, SLC1A4, SLC1A5 and SLC6A14, and downregulation of FOXA2 and GPT2 in THBEc1 cells. FOXA1 knockout changed the consumption of 19 amino acids and the intracellular content of 21 amino acids and reversed the metabolic pattern of Glu and the changes in FOXA2, GLUL, SLC1A3 and SLC6A14 in THBEc1 cells. Additionally, FOXA1 knockout inhibited cell proliferation and further increased the dependence of THBEc1 cells on Glu. In conclusion, FOXA1 knockout partially reversed the change in Glu-Gln metabolism caused by BaP-induced transformation by upregulating the expression of GLUL and SLC1A3. Our findings provide a clue for the possible role of FOXA1 in amino acid metabolism regulation.

Targeting PSAT1 to mitigate metastasis in tumors with p53-72Pro variant

The single-nucleotide polymorphism (SNP) of p53, in particular the codon 72 variants, has recently been implicated as a critical regulator in tumor progression. However, the underlying mechanism remains elusive. Here we found that cancer cells carrying codon 72-Pro variant of p53 showed impaired metastatic potential upon serine supplementation. Proteome-wide mapping of p53-interacting proteins uncovered a specific interaction of the codon 72 proline variant (but not p53^72R) with phosphoserine aminotransferase 1 (PSAT1). Interestingly, p53^72P-PSAT1 interaction resulted in dissociation of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) that otherwise bound to p53^72P, leading to subsequent nuclear translocation of PGC-1α and activation of oxidative phosphorylation (OXPHOS) and tricarboxylic acid (TCA) cycle. Depletion of PSAT1 restored p53^72P-PGC-1α interaction and impeded the OXPHOS and TCA function, resulting in mitochondrial dysfunction and metastasis suppression. Notably, pharmacological targeting the PSAT1-p53^72P interaction by aminooxyacetic acid (AOA) crippled the growth of liver cancer cells carrying the p53^72P variant in both in vitro and patient-derived xenograft models. Moreover, AOA plus regorafenib, an FDA-proved drug for hepatocellular carcinoma and colorectal cancer, achieved a better anti-tumor effect on tumors carrying the p53^72P variant. Therefore, our findings identified a gain of function of the p53^72P variant on mitochondrial function and provided a promising precision strategy to treat tumors vulnerable to p53^72P-PSAT1 perturbation.

A Critical Role of the IL-22-IL-22 Binding Protein Axis in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) ranks among the five most common cancer entities worldwide and leads to hundred-thousands of deaths every year. Despite some groundbreaking therapeutical revelations during the last years, the overall prognosis remains poor. Although the immune system fights malignant transformations with a robust anti-tumor response, certain immune mediators have also been shown to promote cancer development. For example, interleukin (IL)-22 has been associated with HCC progression and worsened prognosis in multiple studies. However, the underlying mechanisms of the pathological role of IL-22-signaling as well as the role of its natural antagonist IL-22 binding protein (IL-22BP) in HCC remain elusive. Here, we corroborate the pathogenic role of IL-22 in HCC by taking advantage of two mouse models. Moreover, we observed a protective role of IL-22BP during liver carcinogenesis. While IL-22 was mainly produced by CD4⁺ T cells in HCC, IL-22BP was abundantly expressed by neutrophils during liver carcinogenesis. Hepatocytes could be identified as a major target of this pathological IL-22-signaling. Moreover, abrogation of IL-22 signaling in hepatocytes in IL22ra1^flox/flox × Alb^Cre+ mice reduced STEAP4 expression-a known oncogene-in HCC in vivo. Likewise, STEAP4 expression correlated with IL22 levels in human HCC samples, but not in healthy liver specimens. In conclusion, these data encourage the development of therapeutical approaches that target the IL-22-IL-22BP axis in HCC.

3D-Epigenomic Regulation of Gene Transcription in Hepatocellular Carcinoma

The fundamental cause of transcription dysregulation in hepatocellular carcinoma (HCC) remains elusive. To investigate the underlying mechanisms, comprehensive 3D-epigenomic analyses are performed in cellular models of THLE2 (a normal hepatocytes cell line) and HepG2 (a hepatocellular carcinoma cell line) using integrative approaches for chromatin topology, genomic and epigenomic variation, and transcriptional output. Comparing the 3D-epigenomes in THLE2 and HepG2 reveal that most HCC-associated genes are organized in complex chromatin interactions mediated by RNA polymerase II (RNAPII). Incorporation of genome-wide association studies (GWAS) data enables the identification of non-coding genetic variants that are enriched in distal enhancers connecting to the promoters of HCC-associated genes via long-range chromatin interactions, highlighting their functional roles. Interestingly, CTCF binding and looping proximal to HCC-associated genes appear to form chromatin architectures that overarch RNAPII-mediated chromatin interactions. It is further demonstrated that epigenetic variants by DNA hypomethylation at a subset of CTCF motifs proximal to HCC-associated genes can modify chromatin topological configuration, which in turn alter RNAPII-mediated chromatin interactions and lead to dysregulation of transcription. Together, the 3D-epigenomic analyses provide novel insights of multifaceted interplays involving genetics, epigenetics, and chromatin topology in HCC cells.