Exclusive liquor and cocktail consumption is associated with at-risk fibrosis among nonheavy alcohol users with metabolic dysfunction-associated steatotic liver disease

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) and alcohol consumption have both increased in recent years, and there is debate as to whether nonheavy alcohol use is safe in MASLD. We analyzed the association between different nonheavy alcohol use patterns and at-risk liver fibrosis among individuals with MASLD.

METHODS

We conducted a cross-sectional study of 1072 eligible National Health and Nutrition Examination Survey participants with MASLD who reported nonheavy alcohol consumption. We used vibration-controlled transient elastography to define the primary outcome of at-risk liver fibrosis as >8.2 kPa (stage F2-F4). Multivariable logistic regression models were used to determine the association of different alcohol consumption patterns (average drinks/day, drinking days/week, weekly alcohol intake, type of alcoholic beverage) and at-risk hepatic fibrosis, controlling for demographic/socioeconomic, lifestyle/dietary, and metabolic risk factors.

RESULTS

Exclusive liquor or cocktail drinkers had a 5.02-fold odds of at-risk fibrosis (95% CI: 1.15-21.95) compared with non-drinkers when controlling for potential confounders. While consuming an average of 2 drinks/day, ≥3 drinking days/week, or 1-3 drinks/week appeared to have a lower association with at-risk fibrosis when controlling for demographic/socioeconomic risk factors, the association was not present after controlling for lifestyle/dietary and metabolic risk factors.

CONCLUSIONS

There is an association between exclusive liquor/cocktail consumption and at-risk liver fibrosis in patients with MASLD who report nonheavy alcohol consumption.

Elevated 2-oxoglutarate antagonizes DNA damage responses in cholangiocarcinoma chemotherapy through regulating aspartate beta-hydroxylase

Cholangiocarcinoma (CCA) is resistant to systemic chemotherapies that kill malignant cells mainly through DNA damage responses (DDRs). Recent studies suggest that the involvement of 2-oxoglutarate (2-OG) dependent dioxygenases in DDRs may be associated with chemoresistance in malignancy, but how 2-OG impacts DDRs in CCA chemotherapy remains elusive. We examined serum 2-OG levels in CCA patients before receiving chemotherapy. CCA patients are classified as progressive disease (PD), partial response (PR), and stable disease (SD) after receiving chemotherapy. CCA patients classified as PD showed significantly higher serum 2-OG levels than those defined as SD and PR. Treating CCA cells with 2-OG reduced DDRs. Overexpression of full-length aspartate beta-hydroxylase (ASPH) could mimic the effects of 2-OG on DDRs, suggesting the important role of ASPH in chemoresistance. Indeed, the knockdown of ASPH improved chemotherapy in CCA cells. Targeting ASPH with a specific small molecule inhibitor also enhanced the effects of chemotherapy. Mechanistically, ASPH modulates DDRs by affecting ATM and ATR, two of the major regulators finely controlling DDRs. More importantly, targeting ASPH improved the therapeutic potential of chemotherapy in two preclinical CCA models. Our data suggested the impacts of elevated 2-OG and ASPH on chemoresistance through antagonizing DDRs. Targeting ASPH may enhance DDRs, improving chemotherapy in CCA patients.

Association of HLA-A, B, and C alleles and cancer susceptibility in 179 solid malignancies

BACKGROUND

The major histocompatibility complex (MHC) genes are known to be capable of influencing the susceptibility of many cancers. All mammalian cells, including cancer cells, express MHC class I molecules consisting of human leukocyte antigens (HLA) A, B, and C. The tumor susceptibility of HLA-A, B, and C alleles has not been studied extensively in solid tumors.

METHODS

HLA-A, B, and C genotypes of 179 solid tumors were collected from Caris Comprehensive Tumor Profiling reports, including 45 GU, 44 GI, 28 pancreaticobiliary, 21 thoracic, 15 breast, 13 Gyn, among others. The tumors were mainly from Caucasians (82%). The HLA allele frequencies in the tumors were compared to those of respective ethnic populations in the US National Marrow Donor Program (NMDP) database. Fisher's exact tests were performed, adjusted P values were calculated using Benjamini-Hochberg's method for false discovery rate (FDR), and Prevalence ratios (PRs) were calculated to quantify associations.

RESULTS

Twenty-one alleles were not listed in the NMDP. Among them, A*11:303 alone was present in 11 carcinomas, and B*08:222 was seen in 4 tumors. Among the alleles listed in the NMDP, C*08:02, B*14:02, A*03:02, and B*44:06 were significantly associated with tumors in Caucasian Americans (PR: 2.50-170), while B*44:02 appeared protective (PR: 0.36). Alleles with less significant associations were listed.

CONCLUSIONS

From the HLA-A, B, and C data of the 179 tumors, we identified several susceptible alleles and one protective allele. Of interest, 21 alleles were not listed in the NMDP. The limited cases prevented our analysis from identifying cancer-susceptible alleles in other races.

Sugar-Sweetened Beverages and Artificially Sweetened Beverages Consumption and the Risk of Nonalcoholic Fatty Liver (NAFLD) and Nonalcoholic Steatohepatitis (NASH)

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are fast becoming the most common chronic liver disease and are often preventable with healthy dietary habits and weight management. Sugar-sweetened beverage (SSB) consumption is associated with obesity and NAFLD. However, the impact of different types of SSBs, including artificially sweetened beverages (ASBs), is not clear after controlling for total sugar intake and total caloric intake. The aim of this study was to examine the association between the consumption of different SSBs and the risk of NAFLD and NASH in US adults. The representativeness of 3739 US adults aged ≥20 years old who had completed 24 h dietary recall interviews and measurements, including dietary, SSBs, smoking, physical activity, and liver stiffness measurements, were selected from the National Health and Nutrition Examination Survey 2017-2020 surveys. Chi-square tests, t-tests, and weighted logistic regression models were utilized for analyses. The prevalence of NASH was 20.5%, and that of NAFLD (defined without NASH) was 32.7% of US. adults. We observed a higher prevalence of NASH/NAFLD in men, Mexican-Americans, individuals with sugar intake from SSBs, light-moderate alcohol use, lower physical activity levels, higher energy intake, obesity, and medical comorbidities. Heavy sugar consumption through SSBs was significantly associated with NAFLD (aOR = 1.60, 95% CI = 1.05-2.45). In addition, the intake of ASBs only (compared to the non-SSB category) was significantly associated with NAFLD (aOR = 1.78, 95% CI = 1.04-3.05), after adjusting for demographic, risk behaviors, and body mass index. A higher sugar intake from SSBs and exclusive ASB intake are both associated with the risk of NAFLD.

Molecular profiling reveals potential targets in cholangiocarcinoma

BACKGROUND

Cholangiocarcinoma (CCA) is a devastating malignancy and has a very poor prognosis if tumors spread outside the liver. Understanding the molecular mechanisms underlying the CCA progression will likely yield therapeutic approaches toward treating this deadly disease.

AIM

To determine the molecular pathogenesis in CCA progression.

METHODS

In silico analysis, in vitro cell culture, CCA transgenic animals, histological, and molecular assays were adopted to determine the molecular pathogenesis.

RESULTS

The transcriptomic data of human CCA samples were retrieved from The Cancer Genome Atlas (TGCA, CHOL), European Bioinformatics Institute (EBI, GAD00001001076), and Gene Expression Omnibus (GEO, GSE107943) databases. Using Gene set enrichment analysis, the cell cycle and Notch related pathways were demonstrated to be significantly activated in CCA in TCGA and GEO datasets. We, through differentially expressed genes, found several cell cycle and notch associated genes were significantly up-regulated in cancer tissues when compared with the non-cancerous control samples. The associated genes, via quantitative real-time PCR and western blotting assays, were further examined in normal human cholangiocytes, CCA cell lines, mouse normal bile ducts, and mouse CCA tumors established by specifically depleting P53 and expressing KrasG12D mutation in the liver. Consistently, we validated that the cell cycle and Notch pathways are up-regulated in CCA cell lines and mouse CCA tumors. Interestingly, targeting cell cycle and notch pathways using small molecules also exhibited significant beneficial effects in controlling tumor malignancy. More importantly, we demonstrated that several cell cycle and Notch associated genes are significantly associated with poor overall survival and disease-free survival using the Log-Rank test.

CONCLUSION

In summary, our study comprehensively analyzed the gene expression pattern of CCA samples using publicly available datasets and identified the cell cycle and Notch pathways are potential therapeutic targets in this deadly disease.

miR-34a regulates macrophage-associated inflammation and angiogenesis in alcohol-induced liver injury

BACKGROUND

Alcohol-associated liver disease (ALD) is a syndrome of progressive inflammatory liver injury and vascular remodeling associated with long-term heavy intake of ethanol. Elevated miR-34a expression, macrophage activation, and liver angiogenesis in ALD and their correlation with the degree of inflammation and fibrosis have been reported. The current study aims to characterize the functional role of miR-34a-regulated macrophage- associated angiogenesis during ALD.

METHODS RESULTS

We identified that knockout of miR-34a in 5 weeks of ethanol-fed mice significantly decreased the total liver histopathology score and miR-34a expression, along with the inhibited liver inflammation and angiogenesis by reduced macrophage infiltration and CD31/VEGF-A expression. Treatment of murine macrophages (RAW 264.7) with lipopolysaccharide (20 ng/mL) for 24 h significantly increased miR-34a expression, along with the enhanced M1/M2 phenotype changes and reduced Sirt1 expression. Silencing of miR-34a significantly increased oxygen consumption rate (OCR) in ethanol treated macrophages, and decreased lipopolysaccharide-induced activation of M1 phenotypes in cultured macrophages by upregulation of Sirt1. Furthermore, the expressions of miR-34a and its target Sirt1, macrophage polarization, and angiogenic phenotypes were significantly altered in isolated macrophages from ethanol-fed mouse liver specimens compared to controls. TLR4/miR-34a knockout mice and miR-34a Morpho/AS treated mice displayed less sensitivity to alcohol-associated injury, along with the enhanced Sirt1 and M2 markers in isolated macrophages, as well as reduced angiogenesis and hepatic expressions of inflammation markers MPO, LY6G, CXCL1, and CXCL2.

CONCLUSION

Our results show that miR-34a-mediated Sirt1 signaling in macrophages is essential for steatohepatitis and angiogenesis during alcohol-induced liver injury. These findings provide new insight into the function of microRNA-regulated liver inflammation and angiogenesis and the implications for reversing steatohepatitis with potential therapeutic benefits in human alcohol-associated liver diseases.

Liver-specific deletion of microRNA-34a alleviates ductular reaction and liver fibrosis during experimental cholestasis

Primary sclerosing cholangitis (PSC) is a chronic liver disease characterized by inflammatory responses and fibrotic scar formation leading to cholestasis. Ductular reaction and liver fibrosis are typical liver changes seen in human PSC and cholestasis patients. The current study aimed to clarify the role of liver-specific microRNA-34a in the cholestasis-associated ductular reaction and liver fibrosis. We demonstrated that miR-34a expression was significantly increased in human PSC livers along with the enhanced ductular reaction, cellular senescence, and liver fibrosis. A liver-specific miR-34a knockout mouse was established by crossing floxed miR-34a mice with albumin-promoter-driven Cre mice. Bile duct ligation (BDL) induced liver injury characterized by necrosis, fibrosis, and immune cell infiltration. In contrast, liver-specific miR-34a knockout in BDL mice resulted in decreased biliary ductular pathology associated with the reduced cholangiocyte senescence and fibrotic responses. The miR-34a-mediated ductular reactions may be functioning through Sirt-1-mediated senescence and fibrosis. The hepatocyte-derived conditioned medium promoted LPS-induced fibrotic responses and senescence in cholangiocytes, and miR-34a inhibitor suppressed these effects, further supporting the involvement of paracrine regulation. In conclusion, we demonstrated that liver-specific miR-34a plays an important role in ductular reaction and fibrotic responses in a BDL mouse model of cholestatic liver disease.

Utility of secretagogin as a marker for the diagnosis of lung neuroendocrine carcinoma

Small-cell lung cancers (SCLC) and large-cell neuroendocrine carcinomas (LCNEC) are two types of high-grade pulmonary neuroendocrine carcinomas (NECs). Diagnostic neuroendocrine markers commonly include synaptophysin, chromogranin A, CD56, and insulinoma-associated protein 1 (INSM1). In this study, the utility of secretagogin (SCGN) was examined in the context of pulmonary NEC diagnosis. The study included 71 pulmonary NEC cases (18 SCLCs, 13 combined-SCLCs, 23 LCNECs, and 17 combined-LCNECs). Immunohistochemical stains of SCGN, synaptophysin, chromogranin A, CD56, and INSM1 were performed on whole tumor sections. The stains were evaluated based on combined staining intensity and the proportion of positive tumor cells. At least mild staining intensity in at least 1% of the cells was considered positive. Bioinformatic studies showed specific SCGN expression in neuroendocrine cells and NECs. SCGN showed diffuse nuclear and cytoplasmic staining in NECs with intra-tumoral heterogeneity. The non-neuroendocrine components were negative. The sensitivity of SCGN was no better than the other established neuroendocrine markers based on all NECs combined or LCNECs/c-LCNECs only. However, the sensitivity of SCGN (71%) was higher than chromogranin A (68%) for SCLCs/c-SCLCs only. The average proportion of SCGN positive tumor cells was 8% higher than chromogranin A (22% versus 14%, P = 0.0332) in all NECs and 18% higher for SCLC and c-SCLC cases only (32% versus 13%, P = 0.0054). The above data showed that SCGN could be used as a supplemental neuroendocrine marker to diagnose SCLC.

Bio-nanoparticle based therapeutic vaccine induces immunogenic response against triple negative breast cancer

Triple negative breast cancer (TNBC) is more aggressive and has a poorer prognosis than other sub-types of breast tumors. This study elucidates how aspartate beta-hydroxylase (ASPH) network promotes drug resistance, and immunotherapy targeting ASPH may improve the efficacy of Doxorubicin (DOX) therapy. An orthotopic model of breast cancer generated by 4T1 cells in immunocompetent mice was used to explore efficacy of immunotherapy in combination with DOX chemotherapy. We evaluated mRNA and protein expression in cultured tumor cells and tissue, as well as assessed cell proliferation, apoptosis, soluble factors/cytokine production, immune cell population diversity and function. We observed that ASPH expression enables TNBC cells to exhibit primary resistance to DOX induced single-/double-strand breaks (SSB/DSB) and enhanced proliferation and survival. Specific bio-nanoparticle based therapeutic vaccine (BNP-TV) promoted ASPH uptake by and maturation of DCs. This BNP-TV combined with DOX induces immunogenic cell death (ICD) in orthotopic xenograft tumors and significantly suppressed primary mammary tumor growth and distant multi-organ metastases. Immunogenic cell death induced by BNP-TV targeting ASPH combined with DOX provides opportunities to treat a highly resistant and metastatic form of breast cancer.

Ten-Eleven Translocation 1 Promotes Malignant Progression of Cholangiocarcinoma With Wild-Type Isocitrate Dehydrogenase 1

BACKGROUND AND AIMS

Cholangiocarcinoma (CCA) is a highly lethal disease without effective therapeutic approaches. The whole-genome sequencing data indicate that about 20% of patients with CCA have isocitrate dehydrogenase 1 (IDH1) mutations, which have been suggested to target 2-oxoglutarate (OG)-dependent dioxygenases in promoting CCA carcinogenesis. However, the clinical study indicates that patients with CCA and mutant IDH1 have better prognosis than those with wild-type IDH1, further complicating the roles of 2-OG-dependent enzymes.

APPROACH AND RESULTS

This study aimed to clarify if ten-eleven translocation 1 (TET1), which is one of the 2-OG-dependent enzymes functioning in regulating 5-hydroxymethylcytosine (5hmC) formation, is involved in CCA progression. By analyzing The Cancer Genome Atlas (TCGA) data set, TET1 mRNA was found to be substantially up-regulated in patients with CCA when compared with noncancerous bile ducts. Additionally, TET1 protein expression was significantly elevated in human CCA tumors. CCA cells were challenged with α-ketoglutarate (α-KG) and dimethyl-α-KG (DM-α-KG), which are cosubstrates for TET1 dioxygenase. The treatments with α-KG and DM-α-KG promoted 5hmC formation and malignancy of CCA cells. Molecular and pharmacological approaches were used to inhibit TET1 activity, and these treatments substantially suppressed 5hmC and CCA carcinogenesis. Mechanistically, it was found that knockdown of TET1 may suppress CCA progression by targeting cell growth and apoptosis through epigenetic regulation. Consistently, targeting TET1 significantly inhibited CCA malignant progression in a liver orthotopic xenograft model by targeting cell growth and apoptosis.

CONCLUSIONS

Our data suggest that expression of TET1 is highly associated with CCA carcinogenesis. It will be important to evaluate TET1 expression in CCA tumors before application of the IDH1 mutation inhibitor because the inhibitor suppresses 2-hydroxyglutarate expression, which may result in activation of TET, potentially leading to CCA malignancy.

Targeting Aspartate Beta-Hydroxylase with the Small Molecule Inhibitor MO-I-1182 Suppresses Cholangiocarcinoma Metastasis

BACKGROUND

Cholangiocarcinoma is a devastating disease with a 2% 5-year survival if the disease has spread outside the liver. The enzyme aspartate beta-hydroxylase (ASPH) has been demonstrated to be highly expressed in cholangiocarcinoma but not in normal bile ducts and found to stimulate tumor cell migration. In addition, it was found that targeting ASPH inhibits cholangiocarcinoma malignant progression. However, it is not clear whether targeting ASPH with the small molecule inhibitor MO-I-1182 suppresses cholangiocarcinoma metastasis. The current study aims to study the efficacy of MO-I-1182 in suppressing cholangiocarcinoma metastasis.

METHODS

The analysis was performed in vitro and in vivo with a preclinical animal model by using molecular and biochemical strategies to regulate ASPH expression and function.

RESULTS

Knockdown of ASPH substantially inhibited cell migration and invasion in two human cholangiocarcinoma cell lines. Targeting ASPH with a small molecule inhibitor suppressed cholangiocarcinoma progression. Molecular mechanism studies demonstrated that knockdown of ASPH subsequently suppressed protein levels of the matrix metalloproteinases. The ASPH knockdown experiments suggest that this enzyme may modulate cholangiocarcinoma metastasis by regulating matrix metalloproteinases expression. Furthermore, using an ASPH inhibitor in a rat cholangiocarcinoma intrahepatic model established with BED-Neu-CL#24 cholangiocarcinoma cells, it was found that targeting ASPH inhibited intrahepatic cholangiocarcinoma metastasis and downstream expression of the matrix metalloproteinases.

CONCLUSION

ASPH may modulate cholangiocarcinoma metastasis via matrix metalloproteinases expression. Taken together, targeting ASPH function may inhibit intrahepatic cholangiocarcinoma metastasis and improve survival.

The interplay between mast cells, pineal gland, and circadian rhythm: Links between histamine, melatonin, and inflammatory mediators

Our daily rhythmicity is controlled by a circadian clock with a specific set of genes located in the suprachiasmatic nucleus in the hypothalamus. Mast cells (MCs) are major effector cells that play a protective role against pathogens and inflammation. MC distribution and activation are associated with the circadian rhythm via two major pathways, IgE/FcεRI- and IL-33/ST2-mediated signaling. Furthermore, there is a robust oscillation between clock genes and MC-specific genes. Melatonin is a hormone derived from the amino acid tryptophan and is produced primarily in the pineal gland near the center of the brain, and histamine is a biologically active amine synthesized from the decarboxylation of the amino acid histidine by the L-histidine decarboxylase enzyme. Melatonin and histamine are previously reported to modulate circadian rhythms by pathways incorporating various modulators in which the nuclear factor-binding near the κ light-chain gene in B cells, NF-κB, is the common key factor. NF-κB interacts with the core clock genes and disrupts the production of pro-inflammatory cytokine mediators such as IL-6, IL-13, and TNF-α. Currently, there has been no study evaluating the interdependence between melatonin and histamine with respect to circadian oscillations in MCs. Accumulating evidence suggests that restoring circadian rhythms in MCs by targeting melatonin and histamine via NF-κB may be promising therapeutic strategy for MC-mediated inflammatory diseases. This review summarizes recent findings for circadian-mediated MC functional roles and activation paradigms, as well as the therapeutic potentials of targeting circadian-mediated melatonin and histamine signaling in MC-dependent inflammatory diseases.

Wnt signaling in liver disease: emerging trends from a bibliometric perspective

Background

The Wnt signaling pathway, an evolutionarily conserved molecular transduction cascade, has been identified as playing a pivotal role in various physiological and pathological processes of the liver, including homeostasis, regeneration, cirrhosis, and hepatocellular carcinoma (HCC). In this study, we aimed to use a bibliometric method to evaluate the emerging trends on Wnt signaling in liver diseases.

Methods

Articles were retrieved from the Web of Science Core Collection. We used a bibliometric software, CiteSpace V 5.3.R4, to analyze the active countries or institutions in the research field, the landmark manuscripts, important subtopics, and evolution of scientific ideas.

Results

In total, 1,768 manuscripts were published, and each was cited 33.12 times on average. The U.S. published most of the articles, and the most active center was the University of Pittsburgh. The top 5 landmark papers were identified by four bibliometric indexes including citation, burstness, centrality, and usage 2013. The clustering process divided the whole area into nine research subtopics, and the two major important subtopics were "liver zonation" and "HCC." Using the "Part-of-Speech" technique, 1,743 terms representing scientific ideas were identified. After 2008, the bursting phrases were "liver development," "progenitor cells," "hepatic stellate cells," "liver regeneration," "liver fibrosis," "epithelial-mesenchymal transition," and etc.

Conclusion

Using bibliometric methods, we quantitatively summarized the advancements and emerging trends in Wnt signaling in liver diseases. These bibliometric findings may pioneer the future direction of this field in the next few years, and further studies are needed.

Chronic ethanol-mediated hepatocyte apoptosis links to decreased TET1 and 5-hydroxymethylcytosine formation

The 5-hydroxymethylcytosine (5hmc) is a newly identified epigenetic modification thought to be regulated by the TET family of proteins. Little information is available about how ethanol consumption may modulate 5hmC formation and alcoholic liver disease (ALD) progression. A rat ALD model was used to study 5hmC in relationship to hepatocyte apoptosis. Human ALD liver samples were also used to validate these findings. It was found that chronic ethanol feeding significantly reduced 5hmC formation in a rat ALD model. There were no significant changes in TET2 and TET3 between the control- and ethanol-fed animals. In contrast, methylcytosine dioxygenase TET1 (TET1) expression was substantially reduced in the ethanol-fed rats and was accompanied by increased hepatocyte apoptosis. Similarly, knockdown of TET1 in human hepatocyte-like cells also significantly promoted apoptosis. Down-regulation of TET1 resulted in elevated expression of the DNA damage marker, suggesting a role for 5hmc in hepatocyte DNA damage as well. Mechanistic studies revealed that inhibition of TET1 promoted apoptotic gene expression. Similarly, targeting TET1 activity by removing cosubstrate promoted apoptosis and DNA damage. Furthermore, treatment with 5-azacitidine significantly mimics these effects, suggesting that chronic ethanol consumption promotes hepatocyte apoptosis and DNA damage by diminishing TET1-mediated 5hmC formation and DNA methylation. In summary, the current study provides a novel molecular insight that TET1-mediated 5hmC is involved in hepatocyte apoptosis in ALD progression.-Ji, C., Nagaoka, K., Zou, J., Casulli, S., Lu, S., Cao, K. Y., Zhang, H., Iwagami, Y., Carlson, R. I., Brooks, K., Lawrence, J., Mueller, W., Wands, J. R., Huang, C.-K. Chronic ethanol-mediated hepatocyte apoptosis links to decreased TET1 and 5-hydroxymethylcytosine formation.

Alanine-glyoxylate aminotransferase 1 (AGXT1) is a novel marker for hepatocellular carcinomas

Arginase-1 has been demonstrated as a marker for hepatocellular carcinoma (HCC) with higher sensitivity and specificity than HepPar-1 and glypican-3. However, its sensitivity is diminished in moderately and poorly differentiated HCCs. In the current study, we evaluated the utility of AGXT1 as a diagnostic marker. Immunostains for AGXT1 and arginase-1 were performed in tissue microarrays of 139 HCCs and 374 gastrointestinal and nongastrointestinal carcinomas. AGXT1 exhibited granular cytoplasmic immunoreactivity in contrast to the diffuse cytoplasmic staining characteristic of arginase-1 in nonneoplastic and neoplastic hepatocytes. Sensitivities of AGXT1 for all HCCs were 90.0% compared to 87.8% for arginase-1. A small number of tumors expressed only 1 of the 2 markers. Sensitivity increased to 92.1% when the presence of either marker was considered positive. Excepting 5 cases of cholangiocarcinoma, both AGXT1 and arginase-1 were negative in all non-HCC tumors with specificities of 98.7%. Our data support the consideration of AGXT1 as a novel hepatocellular marker with equally high specificity and slightly higher sensitivity as compared to arginase-1. AGXT1 may aid in diagnostic workup especially in conjunction with arginase-1 for HCCs that may otherwise defy conventional immunostaining patterns.

Alcohol-mediated miR-34a modulates hepatocyte growth and apoptosis

MicroRNAs (miRs) have been recently shown to be heavily involved in the development of alcoholic liver disease (ALD) and suggested as a potential therapeutic target in ALD. The miR‐34a was consistently reported to be significantly elevated in several ALD rodent models, but it remains unclear how miR‐34a modulates the cellular behaviours of hepatocytes in ALD development and progression. This study aims to characterize alcohol‐induced miR‐34a impact on hepatocytes growth and apoptosis. The miRNA array was performed to assess changes in miRNA after chronic alcohol feeding. Liver and blood samples were used to examine ALD progression. The miR‐34a was overexpressed in human hepatocytes to evaluate its impact on cell growth and apoptosis. Real‐time quantitative PCR and Western blot were used to determine the growth and apoptosis molecular signalling pathways associated with miR‐34a. Alcohol feeding significantly promoted fatty liver progression, serum ALT levels, apoptosis and miR‐34a expression in rat liver. Overexpression of miR‐34a in human hepatocytes suppressed cell growth signallings, including c‐Met, cyclin D1 and cyclin‐dependent kinase 6 (CDK6). The miR‐34a might also inhibit the expression of sirtuin 1 (Sirt1) and its target, B‐cell lymphoma 2. Interestingly, the expression of miR‐34a reverses the suppressive effects of ethanol on cell growth. But, miR‐34a promotes hepatocyte senescence and apoptosis. Although the miR‐34a‐mediated down‐regulation of cell growth‐associated genes may contribute to cell growth retardation, other miR‐34a targets, such as Sirt1, may reverse this phenotype. Future studies will be needed to clarify the role of miR‐34a in ALD progression.

Aspartate beta-hydroxylase promotes cholangiocarcinoma progression by modulating RB1 phosphorylation

Cholangiocarcinoma (CCA) is a highly lethal and aggressive disease. Recently, IDH1/2 mutations have been identified in approximately 20% of CCAs which suggests an involvement of 2-oxoglutarate (2-OG) -dependent dioxygenases in oncogenesis. We investigated if the 2-OG dependent dioxygenase, aspartate beta-hydroxylase (ASPH) was important in tumor development and growth. Immunoassays were used to clarify how ASPH modulates CCA progression by promoting phosphorylation of the retinoblastoma protein (RB1). A xenograft model was employed to determine the role of ASPH on CCA growth. Knockdown of ASPH expression inhibited CCA development and growth by reducing RB1 phosphorylation. Expression of ASPH promoted direct protein interaction between RB1, cyclin-dependent kinases, and cyclins. Treatment with 2-OG-dependent dioxygenase and ASPH inhibitors suppressed the interaction between RB1 and CDK4 as well as RB1 phosphorylation. Knockdown of ASPH expression inhibited CCA progression and RB1 phosphorylation in vivo and they were found to be highly expressed in human CCAs. Knockdown of ASPH expression altered CCA development by modulating RB1 phosphorylation, as one of the major factors regulating the growth of these tumors.

T-complex-associated-testis-expressed 3 (TCTE3) is a novel marker for pancreatobiliary carcinomas

Several markers of pancreatobiliary lineage have been described in the literature. However, none have demonstrated sufficient specificity and sensitivity to warrant diagnostic use. We evaluated the utility of T-complex-associated-testis-expressed 3 (TCTE3) as a pancreatobiliary marker. A set of 247 adenocarcinomas from the gastrointestinal (GI) tract was identified including 18 from the gastroesophageal junction (GEJ), 29 stomach, 17 ampullary, 62 pancreatic, and 16 common bile duct and gallbladder (CBD/GB), 13 non-ampullary small intestine, 32 colon, and 24 rectum. The remainder consisted of 16 cholangiocarcinomas and 20 hepatocellular carcinomas (HCC). Additionally, 163 adenocarcinomas from the breast, gynecologic tract, prostate, urothelium, kidney, and lung were stained for comparison. Immunohistochemistry for TCTE3 and other gastrointestinal markers was performed. Positive expression of TCTE3 was characterized by a strong, well-defined membranous pattern with or without weak cytoplasmic staining. Expression was identified in the normal epithelial cells of pancreatobiliary tree, but staining was absent in normal epithelial cells of esophagus, stomach, and intestine. Hepatocytes, pancreatic acini and islets and other non-epithelial cells were also negative for staining. TCTE3 was expressed in 93.5% of pancreatic ductal adenocarcinomas, 37.5% of CBD/GB adenocarcinomas, 50% of cholangiocarcinomas, 76.4% of ampullary adenocarcinomas, and 33.3% of GEJ adenocarcinomas. Only 3.5% of the gastric, 7.7% of non-ampullary small intestinal and 6.25% of colonic tumors exhibited positive staining. Expression was absent in rectal carcinomas and HCCs. These results suggest that TCTE3 is a useful marker of pancreatobiliary differentiation and may aid in distinguishing these tumors from gastric and intestinal primary tumors.

The role of exosomes in hepatitis, liver cirrhosis and hepatocellular carcinoma

Exosomes are small vesicles that were initially thought to be a mechanism for discarding unneeded membrane proteins from reticulocytes. Their mediation of intercellular communication appears to be associated with several biological functions. Current studies have shown that most mammalian cells undergo the process of exosome formation and utilize exosome‐mediated cell communication. Exosomes contain various microRNAs, mRNAs and proteins. They have been reported to mediate multiple functions, such as antigen presentation, immune escape and tumour progression. This concise review highlights the findings regarding the roles of exosomes in liver diseases, particularly hepatitis B, hepatitis C, liver cirrhosis and hepatocellular carcinoma. However, further elucidation of the contributions of exosomes to intercellular information transmission is needed. The potential medical applications of exosomes in liver diseases seem practical and will depend on the ingenuity of future investigators and their insights into exosome‐mediated biological processes.

Serum chemokine (CC motif) ligand 2 level as a diagnostic, predictive, and prognostic biomarker for prostate cancer

Prostate-specific antigen (PSA) is regarded as the most sensitive biomarker for prostate cancer. Although androgen/androgen receptor (AR) signaling promotes prostate cancer progression, suppression of AR signaling induces chemokine (CC motif) ligand 2 (CCL2), which enables prostate cancer cells to gain metastatic potential. AR-controlled PSA alone may be an unreliable biomarker for patients receiving androgen deprivation therapy. Therefore, we investigated the validity of CCL2 as a complementary biomarker to PSA for prostate cancer. Our in vitro approach of enriching for prostate cancer cells with higher migration potential showed that CCL2 activated cellular migration. Importantly, we found that CCL2 levels were significantly different between men (n = 379) with and without prostate cancer. Patients with CCL2 ≥ 320 pg/mL had worse overall survival and prostate cancer -specific survival than those with CCL2 < 320 pg/mL. A novel risk classification was developed according to the risk factors CCL2 ≥ 320 pg/mL and PSA ≥ 100 ng/mL, and scores of 2, 1, and 0 were defined as poor, intermediate, and good risk, respectively, and clearly distinguished patient outcomes. CCL2 may serve as a novel biomarker for prostate cancer. The novel risk classification based on combining CCL2 and PSA is more reliable than using either alone.

Expression of transforming growth factor β1 promotes cholangiocarcinoma development and progression

BACKGROUND AND AIMS

The role of transforming growth factor beta 1 (TGFβ1) in cholangiocarcinoma (CCA) initiation and growth requires further definition.

METHODS

We employed pharmacological and genetic approaches to inhibit or enhance TGFβ1 signaling, respectively, and determine the cellular mechanisms involved.

RESULTS

It was observed that inhibiting TGFβ1 activity with short hairpin RNA (shRNA) or pharmaceutical agents suppressed CCA development and growth, whereas overexpression of TGFβ1 enhanced CCA tumor size and promoted intrahepatic metastasis in a rat model. Suppression of TGFβ1 activity inhibits downstream target gene expression mediated by miR-34a that includes cyclin D1, CDK6, and c-Met. In addition, "knockdown" of TGFβ1 expression revealed a miR-34a positive feedback mechanism for enhanced p21 expression in CCAs. A miR-34a inhibitor reversed the effects of "knocking down" TGFβ1 on cell growth, migration, cyclin D1, CDK6 and c-Met expression, suggesting that TGFβ1 mediated effects occur, in part, through this miR-34a signaling pathway. Overexpression of TGFβ1 was associated with CCA tumor progression.

CONCLUSIONS

This study suggests that TGFβ1 is involved in CCA tumor progression and participates through miR-34a mediated downstream cascades, and is a target to inhibit CCA development and growth.

Androgen receptor (AR) in cardiovascular diseases

Cardiovascular diseases (CVDs) are still the highest leading cause of death worldwide. Several risk factors have been linked to CVDs, including smoking, diabetes, hyperlipidemia, and gender among others. Sex hormones, especially the androgen and its receptor, androgen receptor (AR), have been linked to many diseases with a clear gender difference. Here, we summarize the effects of androgen/AR on CVDs, including hypertension, stroke, atherosclerosis, abdominal aortic aneurysm (AAA), myocardial hypertrophy, and heart failure, as well as the metabolic syndrome/diabetes and their impacts on CVDs. Androgen/AR signaling exacerbates hypertension, and anti-androgens may suppress hypertension. Androgen/AR signaling plays dual roles in strokes, depending on different kinds of factors; however, generally males have a higher incidence of strokes than females. Androgen and AR differentially modulate atherosclerosis. Androgen deficiency causes elevated lipid accumulation to enhance atherosclerosis; however, targeting AR in selective cells without altering serum androgen levels would suppress atherosclerosis progression. Androgen/AR signaling is crucial in AAA development and progression, and targeting androgen/AR profoundly restricts AAA progression. Men have increased cardiac hypertrophy compared with age-matched women that may be due to androgens. Finally, androgen/AR plays important roles in contributing to obesity and insulin/leptin resistance to increase the metabolic syndrome.

Aspartate β-hydroxylase modulates cellular senescence through glycogen synthase kinase 3β in hepatocellular carcinoma

Aspartate β-hydroxylase (ASPH) is an enzyme overexpressed in human hepatocellular carcinoma (HCC) tumors that participates in the malignant transformation process. We determined if ASPH was a therapeutic target by exerting effects on cellular senescence to retard HCC progression. ASPH knockdown or knockout was achieved by short hairpin RNAs or the CRISPR/Cas9 system, respectively, whereas enzymatic inhibition was rendered by a potent second-generation small molecule inhibitor of ASPH. Alterations of cell proliferation, colony formation, and cellular senescence were evaluated in human HCC cell lines. The potential mechanisms for activating cellular senescence were explored using murine subcutaneous and orthotopic xenograft models. Inhibition of ASPH expression and enzymatic activity significantly reduced cell proliferation and colony formation but induced tumor cell senescence. Following inhibition of ASPH activity, phosphorylation of glycogen synthase kinase 3β and p16 expression were increased to promote senescence, whereas cyclin D1 and proliferating cell nuclear antigen were decreased to reduce cell proliferation. The mechanisms involved demonstrate that ASPH binds to glycogen synthase kinase 3β and inhibits its subsequent interactions with protein kinase B and p38 upstream kinases as shown by coimmunoprecipitation. In vivo experiments demonstrated that small molecule inhibitor treatment of HCC bearing mice resulted in significant dose-dependent reduced tumor growth, induced phosphorylation of glycogen synthase kinase 3β, enhanced p16 expression in tumor cells, and promoted cellular senescence.

CONCLUSIONS

We have identified a new mechanism that promotes HCC growth and progression by modulating senescence of tumor cells; these findings suggest that ASPH enzymatic activity is a novel therapeutic target for HCC.

Anti-Tumor Effects of Second Generation β-Hydroxylase Inhibitors on Cholangiocarcinoma Development and Progression

Cholangiocarcinoma (CCA) has a poor prognosis due to widespread intrahepatic spread. Aspartate β-hydroxylase (ASPH) is a transmembrane protein and catalyzes the hydroxylation of aspartyl and asparaginyl residues in calcium binding epidermal growth factor (cbEGF)-like domains of various proteins, including Notch receptors and ligands. ASPH is highly overexpressed (>95%) in human CCA tumors. We explored the molecular mechanisms by which ASPH mediated the CCA malignant phenotype and evaluated the potential of ASPH as a therapeutic target for CCA. The importance of expression and enzymatic activity of ASPH for CCA growth and progression was examined using shRNA "knockdown" and a mutant construct that reduced its catalytic activity. Second generation small molecule inhibitors (SMIs) of β-hydroxylase activity were developed and used to target ASPH in vitro and in vivo. Subcutaneous and intrahepatic xenograft rodent models were employed to determine anti-tumor effects on CCA growth and development. It was found that the enzymatic activity of ASPH was critical for mediating CCA progression, as well as inhibiting apoptosis. Mechanistically, ASPH overexpression promoted Notch activation and modulated CCA progression through a Notch1-dependent cyclin D1 pathway. Targeting ASPH with shRNAs or a SMI significantly suppressed CCA growth in vivo.

Concise review: androgen receptor differential roles in stem/progenitor cells including prostate, embryonic, stromal, and hematopoietic lineages

Stem/progenitor (S/P) cells are special types of cells that have the ability to generate tissues throughout their entire lifetime and play key roles in the developmental process. Androgen and the androgen receptor (AR) signals are the critical determinants in male gender development, suggesting that androgen and AR signals might modulate the behavior of S/P cells. In this review, we summarize the AR effects on the behavior of S/P cells, including self-renewal, proliferation, apoptosis, and differentiation in normal S/P cells, as well as proliferation, invasion, and self-renewal in prostate cancer S/P cells. AR plays a protective role in the oxidative stress-induced apoptosis in embryonic stem cells. AR inhibits the self-renewal of embryonic stem cells, bone marrow stromal cells, and prostate S/P cells, but promotes their differentiation except for adipogenesis. However, AR promotes the proliferation of hematopoietic S/P cells and stimulates hematopoietic lineage differentiation. In prostate cancer S/P cells, AR suppresses their self-renewal, metastasis, and invasion. Together, AR differentially influences the characteristics of normal S/P cells and prostate cancer S/P cells, and targeting AR might improve S/P cell transplantation therapy, especially in embryonic stem cells and bone marrow stromal cells.

Progenitor-like cells derived from mouse kidney protect against renal fibrosis in a remnant kidney model via decreased endothelial mesenchymal transition

Introduction

Pathophysiological changes associated with chronic kidney disease impair angiogenic processes and increase renal fibrosis. Progenitor-like cells derived from adult kidney have been previously used to promote regeneration in acute kidney injury, even though it remained unclear whether the cells could be beneficial in chronic kidney disease (CKD).

Methods

In this study, we established a CKD model by five-sixths nephrectomy and mouse kidney progenitor-like cells (MKPCs) were intravenously administered weekly for 5 weeks after establishing CKD. We examined the impact of MKPCs on the progression of renal fibrosis and the potential of MKPCs to preserve the angiogenic process and prevent endothelial mesenchymal transition in vivo and in vitro.

Results

Our results demonstrate that the MKPCs delayed interstitial fibrosis and the progression of glomerular sclerosis and ameliorated the decline of kidney function. At 17 weeks, the treated mice exhibited lower blood pressures, higher hematocrit levels, and larger kidney sizes than the control mice. In addition, the MKPC treatment prolonged the survival of the mice with chronic kidney injuries. We observed a decreased recruitment of macrophages and myofibroblasts in the interstitium and the increased tubular proliferation. Notably, MKPC both decreased the level of vascular rarefaction and prevented endothelial mesenchymal transition (EndoMT) in the remnant kidneys. Moreover, the conditioned medium from the MKPCs ameliorated endothelial cell death under hypoxic culture conditions and prevented TGF-β-induced EndoMT through downregulation of phosphorylated Smad 3 in vitro.

Conclusions

MKPCs may be a beneficial treatment for kidney diseases characterized by progressive renal fibrosis. The enhanced preservation of angiogenic processes following MKPC injections may be associated with decreased fibrosis in the remnant kidney. These findings provide further understanding of the mechanisms involved in these processes and will help develop new cell-based therapeutic strategies for regenerative medicine in renal fibrosis.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-015-0241-8) contains supplementary material, which is available to authorized users.

Androgen receptor promotes abdominal aortic aneurysm development via modulating inflammatory interleukin-1α and transforming growth factor-β1 expression

Sex difference is a risk factor for abdominal aortic aneurysm (AAA) formation yet the reason for male predominance remains unclear. Androgen and the androgen receptor (AR) influence the male sex difference, indicating that AR signaling may affect AAA development. Using angiotensin II–induced AAA in apolipoprotein E null mouse models (82.4% AAA incidence), we found that mice lacking AR failed to develop AAA and aorta had dramatically reduced macrophages infiltration and intact elastic fibers. These findings suggested that AR expression in endothelial cells, macrophages, or smooth muscle cells might play a role in AAA development. Selective knockout of AR in each of these cell types further demonstrated that mice lacking AR in macrophages (20% AAA incidence) or smooth muscle cells (12.5% AAA incidence) but not in endothelial cells (71.4% AAA incidence) had suppressed AAA development. Mechanism dissection showed that AR functioned through modulation of interleukin-1α (IL-1α) and transforming growth factor-β1 signals and by targeting AR with the AR degradation enhancer ASC-J9 led to significant suppression of AAA development. These results demonstrate the underlying mechanism by which AR influences AAA development is through IL-1α and transforming growth factor-β1, and provides a potential new therapy to suppress/prevent AAA by targeting AR with ASC-J9.

Aspartate β-Hydroxylase expression promotes a malignant pancreatic cellular phenotype

Pancreatic cancer (PC) is one of the leading causes of cancer related deaths due to aggressive progression and metastatic spread. Aspartate β-hydroxylase (ASPH), a cell surface protein that catalyzes the hydroxylation of epidermal growth factor (EGF)-like repeats in Notch receptors and ligands, is highly overexpressed in PC. ASPH upregulation confers a malignant phenotype characterized by enhanced cell proliferation, migration, invasion and colony formation in vitro as well as PC tumor growth in vivo. The transforming properties of ASPH depend on enzymatic activity. ASPH links PC growth factor signaling cascades to Notch activation. A small molecule inhibitor of β-hydroxylase activity was developed and found to reduce PC growth by downregulating the Notch signaling pathway. These findings demonstrate the critical involvement of ASPH in PC growth and progression, provide new insight into the molecular mechanisms leading to tumor development and growth and have important therapeutic implications.

Restoration of Wnt/β-catenin signaling attenuates alcoholic liver disease progression in a rat model

BACKGROUND & AIMS

Alcoholic liver disease (ALD) is characterized by the development of fatty liver, alcoholic hepatitis, fibrosis and cirrhosis. However, the underlying mechanism(s) associated with progression remains elusive. Pro-inflammatory cytokines have been implicated in ALD progression due to pro-apoptotic effects on hepatocytes. Wnt/β-catenin signaling recently has been shown to promote inflammation and apoptosis, suggesting that activation of this signaling pathway may modulate ALD progression. The current study was designed to test whether pharmacological activation of Wnt/β-catenin signaling altered ALD development and progression in a rat model.

METHODS

Adult male Long Evans rats were fed with isocaloric liquid diets containing 0% or 37% ethanol for 8 weeks, and also treated with Wnt agonist during the last 3 weeks of the feeding regimen. Liver and blood samples were subjected to histology, TUNEL assay, immunoblot analysis, real-time quantitative PCR, and alanine transaminase (ALT) assay.

RESULTS

Wnt/β-catenin signaling was negatively correlated with Foxo3A expression and reduced steatosis, cellular injury and apoptosis in ALD rats. Mutation experiments demonstrated that Foxo3A was critical for modulating these effects. Activation of Wnt/β-catenin signaling suppressed Foxo3A-induced apoptosis through upregulation of serum/glucocorticoid regulated kinase 1 (SGK1). Moreover, pharmacological restoration of Wnt/β-catenin signaling reduced ALD progression in vivo.

CONCLUSIONS

Wnt/β-catenin signaling plays a protective role in ALD progression via antagonizing Foxo3A-induced apoptosis, and activation of the Wnt/β-catenin signaling cascade attenuates ALD progression.

Chronic Ethanol-Induced Impairment of Wnt/β-Catenin Signaling is Attenuated by PPAR-δ Agonist

BACKGROUND

The Wnt/β-catenin pathway regulates liver growth, repair, and regeneration. Chronic ethanol (EtOH) exposure blunts normal liver regenerative responses, in part by inhibiting insulin/IGF signaling, and correspondingly, previous studies showed that EtOH-impaired liver regeneration could be restored by insulin sensitizer (proliferator-activated receptor [PPAR]-δ agonist) treatment. As Wnt/β-catenin functions overlap and cross talk with insulin/IGF pathways, we investigated the effects of EtOH exposure and PPAR-δ agonist treatment on Wnt pathway gene expression in relation to liver regeneration.

METHODS

Adult male Long Evans rats were fed with isocaloric liquid diets containing 0 or 37% EtOH for 8 weeks and also treated with vehicle or a PPAR-δ agonist during the last 3 weeks of the feeding regimen. The rats were then subjected to 70% partial hepatectomy (PH) and livers harvested at various post-PH time points were used to quantitate expression of 19 Wnt pathway genes using Quantigene 2.0 Multiplex Assay.

RESULTS

EtOH broadly inhibited expression of Wnt/β-catenin signaling-related genes, including down-regulation of Wnt1, Fzd3, Lef1, and Bcl9 throughout the post-PH time course (0 to 72 hours), and suppression of Wnt7a, Ccnd1, Fgf4, Wif1, Sfrp2, and Sfrp5 at 18- and 24-hour post-PH time points. PPAR-δ agonist treatments rescued the EtOH-induced suppression of Wnt1, Wnt7a, Fzd3, Lef1, Bcl9, Ccnd1, and Sfrp2 gene expression in liver, corresponding with the improvements in DNA synthesis and restoration of hepatic architecture.

CONCLUSIONS

Chronic high-dose EtOH exposures inhibit Wnt signaling, which likely contributes to the impairments in liver regeneration. Therapeutic effects of PPAR-δ agonists extend beyond restoration of insulin/IGF signaling mechanisms and are mediated in part by enhancement of Wnt pathway signaling. Future studies will determine the degree to which targeted restoration of Wnt signaling is sufficient to improve liver regeneration and remodeling in the context of chronic EtOH exposure.

A cell-surface β-hydroxylase is a biomarker and therapeutic target for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has a poor prognosis as a result of widespread intra- and extrahepatic metastases. There is an urgent need to understand signaling cascades that promote disease progression. Aspartyl-(asparaginyl)-β-hydroxylase (ASPH) is a cell-surface enzyme that generates enhanced cell motility, migration, invasion, and metastatic spread in HCC. We hypothesize that inhibition of its enzymatic activity could have antitumor effects. Small molecule inhibitors (SMIs) were developed based on the crystal structure of the ASPH catalytic site followed by computer-assisted drug design. Candidate compounds were tested for inhibition of β-hydroxylase activity and selected for their capability to modulate cell proliferation, migration, invasion, and colony formation in vitro and to inhibit HCC tumor growth in vivo using orthotopic and subcutaneous murine models. The biological effects of SMIs on the Notch signaling cascade were evaluated. The SMI inhibitor, MO-I-1100, was selected because it reduced ASPH enzymatic activity by 80% and suppressed HCC cell migration, invasion, and anchorage-independent growth. Furthermore, substantial inhibition of HCC tumor growth and progression was observed in both animal models. The mechanism(s) for this antitumor effect was associated with reduced activation of Notch signaling both in vitro and in vivo.

CONCLUSIONS

These studies suggest that the enzymatic activity of ASPH is important for hepatic oncogenesis. Reduced β-hydroxylase activity generated by the SMI MO-I-1100 leads to antitumor effects through inhibiting Notch signaling cascade in HCC. ASPH promotes the generation of an HCC malignant phenotype and represents an attractive molecular target for therapy of this fatal disease.

Androgen receptor enhances kidney stone-CaOx crystal formation via modulation of oxalate biosynthesis & oxidative stress

Males develop kidney stones far more frequently than females with a ratio of 2–3:1, suggesting that androgen receptor (AR) signaling might play a key role in the development of nephrolithiasis. Using the cre-loxP system to selectively knock out AR in glyoxylate-induced calcium oxalate (CaOx) crystal mouse models, we found that the mice lacking hepatic AR had less oxalate biosynthesis, which might lead to lower CaOx crystal formation, and that the mice lacking kidney proximal or distal epithelial AR also had lower CaOx crystal formation. We found that AR could directly up-regulate hepatic glycolate oxidase and kidney epithelial NADPH oxidase subunit p22-PHOX at the transcriptional level. This up-regulation might then increase oxalate biosynthesis and oxidative stress that resulted in induction of kidney tubular injury. Targeting AR with the AR degradation enhancer ASC-J9 led to suppression of CaOx crystal formation via modulation of oxalate biosynthesis and oxidative stress in both in vitro and in vivo studies. Taken together, these results established the roles of AR in CaOx crystal formation.

Outcomes and predictive factors of prostate cancer patients with extremely high prostate-specific antigen level

PURPOSE

Prostate-specific antigen (PSA) is a useful biomarker of prostate cancer (PCa). High-risk localized PCa is defined using T stage, Gleason score (GS), and PSA. However, PSA level defining high-risk PCa is at most 20 ng/mL. In PCa patients with high PSA, it is unclear whether PSA itself can be a prognostic factor.

METHODS

Of 642 patients who were diagnosed as PCa, 90 patients with PSA > 100 ng/mL were retrospectively analyzed. Patients were divided into three groups according to PSA level: very high (>1,000 ng/mL), moderately high (200-1,000 ng/mL), and slightly high (100-200 ng/mL).

RESULTS

There were no significant differences in overall survival or PCa-specific survival (PCaSS) among the three groups. Regardless of PSA level, high M stage and GS significantly reduced PCaSS. When the risk classification was made using M stage and GS (high risk = M1 and GS ≥ 9, low risk = M0 and GS < 9, and intermediate risk = others), PCaSS was significantly different among high-, intermediate-, and low-risk groups with 5-year survival rates of 58.2, 80.6, and 100 %, respectively. Although there were no differences in treatment performed during the castration-resistant stage, patients undergoing alternative anti-androgen and zoledronic acid treatment had better PCaSS after being castration-resistant.

CONCLUSIONS

As PSA could not be a prognostic factor in PCa patients with high PSA > 100 ng/mL, the novel risk classification using M stage and GS may help clinicians to predict PCaSS and to plan follow-up schedules after diagnosis.

New therapy via targeting androgen receptor in monocytes/macrophages to battle atherosclerosis

The male sex has a higher risk to develop coronary artery diseases, including atherosclerosis. The androgen receptor (AR) is expressed in several atherosclerosis-associated cell types, including monocytes/macrophages, endothelial cells (ECs), and smooth muscle cells (SMCs), but its pathophysiological role in each cell type during the development of atherosclerotic lesions remains unclear. Using the Cre-loxP system, we selectively knocked out AR in these 3 cell types and the resultant AR knockout (ARKO) mice, monocyte/macrophage ARKO, EC-ARKO, and SMC-ARKO, were then crossed with the low-density lipoprotein receptor (LDLR) deficient (LDLR(-/-)) mice to develop monocyte/macrophage ARKO-LDLR(-/-), EC-ARKO-LDLR(-/-), and SMC-ARKO-LDLR(-/-) mice for the study of atherosclerosis. The results showed that the monocyte/macrophage ARKO-LDLR(-/-) mice had reduced atherosclerosis compared with the wild-type-LDLR(-/-) control mice. However, no significant difference was detected in EC-ARKO-LDLR(-/-) and SMC-ARKO-LDLR(-/-) mice compared with wild-type-LDLR(-/-) mice, suggesting that the AR in monocytes/macrophages, and not in ECs and SMCs, plays a major role to promote atherosclerosis. Molecular mechanism dissection suggested that AR in monocytes/macrophages upregulated the tumor necrosis factor-α, integrin β2, and lectin-type oxidized LDL receptor 1 molecules that are involved in 3 major inflammation-related processes in atherosclerosis, including monocytes/macrophages migration and adhesion to human umbilical vein ECs, and subsequent foam cell formation. Targeting AR via the AR degradation enhancer, ASC-J9, in wild-type-LDLR(-/-) mice showed similar effects as seen in monocyte/macrophage ARKO-LDLR(-/-) mice with little influence on lipid profile. In conclusion, the AR in monocytes/macrophages plays key roles in atherosclerosis and targeting AR with ASC-J9 may represent a new potential therapeutic approach to battle atherosclerosis.

A mouse model of liver injury to evaluate paracrine and endocrine effects of bone marrow mesenchymal stem cells

Liver fibrosis is the result of chronic liver disease, which is caused by sustaining multiple damage or injury to the liver. While the liver continues to receive injuries, it suffers from the wound healing process and this eventually leads to the derangement of the liver architecture. Recently, bone marrow-derived mesenchymal stem cells (BM-MSCs) have been suggested to have therapeutic effects in treating liver fibrosis. Here, we describe the isolation, purification, culture, and transplantation of BM-MSCs in the liver fibrosis mouse model, and the assessment of paracrine and endocrine (including androgens and/or estrogens) effects of BM-MSCs in the in vitro cell culture system.

Determination of androgen receptor degradation enhancer ASC-J9(®) in mouse sera and organs with liquid chromatography tandem mass spectrometry

A novel androgen receptor (AR) degradation enhancer ASC-J9(®) has displayed beneficial effects during the in vitro and in vivo studies for treatment of prostate cancer, liver cancer, bladder cancer and spinal and bulbar muscular atrophy (SBMA). It works mainly via the degradation of AR with minimal side effects on the tested mice. Here we developed a fast, robust and more sensitive method for the quantification of ASC-J9(®) in 100μL of mouse serum by using liquid chromatography tandem mass spectrometry (LC-MS/MS). The limit of quantification (LOQ) was found to be 5nM for ASCJ9(®). This method was successfully applied to investigate the pharmacokinetics of ASC-J9(®) in mice serum samples and also the distribution of the drug in various mice organs after single dose injection with results showing that ASC-J9(®) could be quickly absorbed in vivo and had a relatively slow elimination half-life of 5.45h. The ASC-J9(®) also exhibited a higher tendency to accumulate in organs such as liver, testes and prostate.

Targeting stromal androgen receptor suppresses prolactin-driven benign prostatic hyperplasia (BPH)

Stromal-epithelial interaction plays a pivotal role to mediate the normal prostate growth, the pathogenesis of benign prostatic hyperplasia (BPH), and prostate cancer development. Until now, the stromal androgen receptor (AR) functions in the BPH development, and the underlying mechanisms remain largely unknown. Here we used a genetic knockout approach to ablate stromal fibromuscular (fibroblasts and smooth muscle cells) AR in a probasin promoter-driven prolactin transgenic mouse model (Pb-PRL tg mice) that could spontaneously develop prostate hyperplasia to partially mimic human BPH development. We found Pb-PRL tg mice lacking stromal fibromuscular AR developed smaller prostates, with more marked changes in the dorsolateral prostate lobes with less proliferation index. Mechanistically, prolactin mediated hyperplastic prostate growth involved epithelial-stromal interaction through epithelial prolactin/prolactin receptor signals to regulate granulocyte macrophage-colony stimulating factor expression to facilitate stromal cell growth via sustaining signal transducer and activator of transcription-3 activity. Importantly, the stromal fibromuscular AR could modulate such epithelial-stromal interacting signals. Targeting stromal fibromuscular AR with the AR degradation enhancer, ASC-J9(®), led to the reduction of prostate size, which could be used in future therapy.

Increased chemosensitivity via targeting testicular nuclear receptor 4 (TR4)-Oct4-interleukin 1 receptor antagonist (IL1Ra) axis in prostate cancer CD133+ stem/progenitor cells to battle prostate cancer

Prostate cancer (PCa) stem/progenitor cells are known to have higher chemoresistance than non-stem/progenitor cells, but the underlying molecular mechanism remains unclear. We found the expression of testicular nuclear receptor 4 (TR4) is significantly higher in PCa CD133(+) stem/progenitor cells compared with CD133(-) non-stem/progenitor cells. Knockdown of TR4 levels in the established PCa stem/progenitor cells and the CD133(+) population of the C4-2 PCa cell line with lentiviral TR4 siRNA led to increased drug sensitivity to the two commonly used chemotherapeutic drugs, docetaxel and etoposide, judging from significantly reduced IC50 values and increased apoptosis in the TR4 knockdown cells. Mechanism dissection studies found that suppression of TR4 in these stem/progenitor cells led to down-regulation of Oct4 expression, which, in turn, down-regulated the IL-1 receptor antagonist (IL1Ra) expression. Neutralization experiments via adding these molecules into the TR4 knockdown PCa stem/progenitor cells reversed the chemoresistance, suggesting that the TR4-Oct4-IL1Ra axis may play a critical role in the development of chemoresistance in the PCa stem/progenitor cells. Together, these studies suggest that targeting TR4 may alter chemoresistance of PCa stem/progenitor cells, and this finding provides the possibility of targeting TR4 as a new and better approach to overcome the chemoresistance problem in PCa therapeutics.

Targeting androgen receptor in bone marrow mesenchymal stem cells leads to better transplantation therapy efficacy in liver cirrhosis

Transplantation of bone marrow mesenchymal stem cells (BM-MSCs) has been considered as an alternative therapy, replacing liver transplantation in clinical trials, to treat liver cirrhosis, an irreversible disease that may eventually lead to liver cancer development. However, low survival rate of the BM-MSCs leading to unsatisfactory efficacy remains a major concern. Gender differences have been suggested in BM-MSCs therapeutic application, but the effect of the androgen receptor (AR), a key factor in male sexual phenotype, in this application is not clear. Using two liver cirrhosis mouse models induced by CCl4 or thioacetamide, we showed that targeting AR in the BM-MSCs improved their self-renewal and migration potentials and increased paracrine effects to exert anti-inflammatory and anti-fibrotic actions to enhance liver repair. Mechanism dissection studies suggested that knocking out AR in BM-MSCs led to improved self-renewal and migration by alteration of the signaling of epidermal growth factor receptor and matrix metalloproteinase 9 and resulted in suppression of infiltrating macrophages and hepatic stellate cell activation through modulation of interleukin (IL)1R/IL1Ra signaling. Therapeutic approaches using either AR/small interfering RNA or the AR degradation enhancer, ASC-J9, to target AR in BM-MSCs all led to increased efficacy for liver repair.

CONCLUSION

Targeting AR, a key factor in male sexual phenotype, in BM-MSCs improves transplantation therapeutic efficacy for treating liver fibrosis.

Suppression of androgen receptor enhances the self-renewal of mesenchymal stem cells through elevated expression of EGFR

Bone marrow derived mesenchymal stem cells (BM-MSCs) have been widely applied in several clinical trials of diseases, such as myocardial infarction, liver cirrhosis, neurodegenerative disease, and osteogenesis imperfecta. Although most studies demonstrated that transplantation of BM-MSCs did exert a temporary relief and short-term therapeutic effects, eventually all symptoms recur, therefore it is essential to improve the therapeutic efficacy of transplantation by either elevating the self-renewal of BM-MSCs or enhancing their survival rate. Herein we demonstrated that the BM-MSCs and adipocyte derived mesenchymal stem cells (ADSCs) isolated from the androgen receptor (AR) knockout mice have higher self-renewal ability than those obtained from the wild-type mice. Knockdown of AR in MSC cell lines exhibited similar results. Mechanistic dissection studies showed that the depletion of AR resulted in activation of Erk and Akt signaling pathways through epidermal growth factor receptor (EGFR) activation or pathway to mediate higher self-renewal of BM-MSCs. Targeting AR signals using ASC-J9® (an AR degradation enhancer), hydroxyflutamide (antagonist of AR), and AR-siRNA all led to enhanced self-renewal of MSCs, suggesting the future possibility of using these anti-AR agents in therapeutic approaches.

New therapeutic approach to suppress castration-resistant prostate cancer using ASC-J9 via targeting androgen receptor in selective prostate cells

Using androgen receptor (AR) knockout mice to determine AR functions in selective prostate cancer (PCa) cells, we determined that AR might play differential roles in various cell types, either to promote or suppress PCa development/progression. These observations partially explain the failure of current androgen deprivation therapy (ADT) to reduce/prevent androgen binding to AR in every cell. Herein, we identified the AR degradation enhancer ASC-J9, which selectively degrades AR protein via interruption of the AR-AR selective coregulator interaction. Such selective interruption could, therefore, suppress AR-mediated PCa growth in the androgen-sensitive stage before ADT and in the castration-resistant stage after ADT. Mechanistic dissection suggested that ASC-J9 could activate the proteasome-dependent pathway to promote AR degradation through the enhanced association of AR-Mdm2 complex. The consequences of ASC-J9-promoted AR degradation included reduced androgen binding to AR, AR N-C terminal interaction, and AR nuclear translocation. Such inhibitory regulation could then result in suppression of AR transactivation and AR-mediated cell growth in eight different mouse models, including intact or castrated nude mice xenografted with androgen-sensitive LNCaP cells or androgen-insensitive C81 cells and castrated nude mice xenografted with castration-resistant C4-2 and CWR22Rv1 cells, and TRAMP and Pten(+/-) mice. These results demonstrate that ASC-J9 could serve as an AR degradation enhancer that effectively suppresses PCa development/progression in the androgen-sensitive and castration-resistant stages.

Targeting the unique methylation pattern of androgen receptor (AR) promoter in prostate stem/progenitor cells with 5-aza-2'-deoxycytidine (5-AZA) leads to suppressed prostate tumorigenesis

Androgen receptor (AR) expression surveys found that normal prostate/prostate cancer (PCa) stem/progenitor cells, but not embryonic or mesenchymal stem cells, expressed little AR with high methylation in the AR promoter. Mechanism dissection revealed that the differential methylation pattern in the AR promoter could be due to differential expression of methyltransferases and binding of methylation binding protein to the AR promoter region. The low expression of AR in normal prostate/PCa stem/progenitor cells was reversed after adding 5-aza-2'-deoxycytidine, a demethylating agent, which could then lead to decreased stemness and drive cells into a more differentiated status, suggesting that the methylation in the AR promoter of prostate stem/progenitor cells is critical not only in maintaining the stemness but also critical in protection of cells from differentiation. Furthermore, induced AR expression, via alteration of its methylation pattern, led to suppression of the self-renewal/proliferation of prostate stem/progenitor cells and PCa tumorigenesis in both in vitro assays and in vivo orthotopic xenografted mouse studies. Taken together, these data prove the unique methylation pattern of AR promoter in normal prostate/PCa stem/progenitor cells and the influence of AR on their renewal/proliferation and differentiation. Targeting PCa stem/progenitor cells with alteration of methylated AR promoter status might provide a new potential therapeutic approach to battle PCa because the PCa stem/progenitor cells have high tumorigenicity.

New therapy targeting differential androgen receptor signaling in prostate cancer stem/progenitor vs. non-stem/progenitor cells

The androgen deprivation therapy (ADT) to systematically suppress/reduce androgens binding to the androgen receptor (AR) has been the standard therapy for prostate cancer (PCa); yet, most of ADT eventually fails leading to the recurrence of castration resistant PCa. Here, we found that the PCa patients who received ADT had increased PCa stem/progenitor cell population. The addition of the anti-androgen, Casodex, or AR-siRNA in various PCa cells led to increased stem/progenitor cells, whereas, in contrast, the addition of functional AR led to decreased stem/progenitor cell population but increased non-stem/progenitor cell population, suggesting that AR functions differentially in PCa stem/progenitor vs. non-stem/progenitor cells. Therefore, the current ADT might result in an undesired expansion of PCa stem/progenitor cell population, which explains why this therapy fails. Using various human PCa cell lines and three different mouse models, we concluded that targeting PCa non-stem/progenitor cells with AR degradation enhancer ASC-J9 and targeting PCa stem/progenitor cells with 5-azathioprine and γ-tocotrienol resulted in a significant suppression of the tumors at the castration resistant stage. This suggests that a combinational therapy that simultaneously targets both stem/progenitor and non-stem/progenitor cells will lead to better therapeutic efficacy and may become a new therapy to battle the PCa before and after castration resistant stages.

Hepatic androgen receptor suppresses hepatocellular carcinoma metastasis through modulation of cell migration and anoikis

Early reports suggested androgen/androgen receptor (AR) signals promote hepatocarcinogenesis. However, all antiandrogen clinical trials failed in advanced hepatocellular carcinoma (HCC) without reasonable explanations. We examined AR functions in HCC cancer metastasis in this study. We examined hepatic AR roles in HCC metastasis by comparing liver hepatocyte AR knockout and wildtype in a carcinogen-induced HCC mouse model. We examined tumor histology, cancer metastatic risks, and cancer survival in vivo, as well as cell anoikis and migration using primary hepatic tumor culture in vitro. We also examined therapeutic potentials of AR expression combined with the molecular targeting agent sorafenib in an HCC metastasis mouse model. We found a novel cancer phenotype in which mice lacking hepatic AR developed more undifferentiated tumors and larger tumor size at the metastatic stage. These mice also died earlier with increased lung metastasis, suggesting that hepatic AR may play dual yet opposite roles to promote HCC initiation but suppress HCC metastasis. Mechanistic dissection found that hepatic AR could enhance anoikis and suppress migration of HCC cells by way of suppression of p38 phosphorylation/activation and the nuclear factor kappa B (NF-κB)/matrix metallopeptidase 9 (MMP9) pathway, respectively. In addition, the in vivo preclinical trials concluded that a combination therapy of increased AR expression and reduced multiple-kinase inhibitor (sorafenib) exhibited better therapeutic efficacy.

CONCLUSION

Our study demonstrates that AR could orchestrate intrahepatic signaling hierarchies and cellular behaviors, consequently affect HCC progression. Results from combination therapy shed light on developing new therapeutic paradigms for battling HCC at later metastatic stages.

Loss of stromal androgen receptor leads to suppressed prostate tumourigenesis via modulation of pro-inflammatory cytokines/chemokines

Stromal-epithelial interaction is crucial to mediate normal prostate and prostate cancer (PCa) development. The indispensable roles of mesenchymal/stromal androgen receptor (AR) for the prostate organogenesis have been demonstrated by using tissue recombination from wild-type and testicular feminized mice. However, the stromal AR functions in the tumour microenvironment and the underlying mechanisms governing the interactions between the epithelium and stroma are not completely understood. Here, we have established the first animal model with AR deletion in stromal fibromuscular cells (dARKO, AR knockout in fibroblasts and smooth muscle cells) in the Pten(+/-) mouse model that can spontaneously develop prostatic intraepithelial neoplasia (PIN). We found that loss of stromal fibromuscular AR led to suppression of PIN lesion development with alleviation of epithelium proliferation and tumour-promoting microenvironments, including extracellular matrix (ECM) remodelling, immune cell infiltration and neovasculature formation due, in part, to the modulation of pro-inflammatory cytokines/chemokines. Finally, targeting stromal fibromuscular AR with the AR degradation enhancer, ASC-J9®, resulted in the reduction of PIN development/progression, which might provide a new approach to suppress PIN development.