Hydroxysteroid sulfotransferase SULT2B1b promotes hepatocellular carcinoma cells proliferation in vitro and in vivo

Knockdown of sulfotransferase 2B1 suppresses cell migration, invasion and promotes apoptosis in ovarian carcinoma cells via targeting annexin A9

BACKGROUND

Sulfotransferase family 2B member 1 (SULT2B1) has been reported to play oncogenic role in many types of cancers. Nevertheless, the role that SULT2B1 played in ovarian cancer (OC) and the hidden molecular mechanism is obscure.

METHODS

Expression of SULT2B1 in OC was analyzed by GEPIA database. qRT-PCR and western blot (WB) was applied for the appraisement of SULT2B1 and Annexin A9 (ANXA9) in OC cell lines. The capabilities of cells to proliferate, migrate and invade were assessed with CCK-8 assay, wound healing assay, along with transwell assay. Cell apoptotic level was estimated utilizing flow cytometry. WB was employed for the evaluation of migration- and apoptosis-related proteins. Bioinformatic analysis and co-immunoprecipitation were used to predict and verify the combination of SULT2B1 and ANXA9.

RESULTS

The data showed that SULT2B1 and ANXA9 were upregulated in OC cells. SULT2B1 depletion suppressed the proliferative, migrative, and invasive capabilities of SKOV3 cells but facilitated the cell apoptosis. SULT2B1-regulated ANXA9 expression and were proved to bind to ANXA9. Additionally, ANXA9 deficiency exhibited the same impacts on cell migrative, invasive capability and apoptotic level as SULT2B1 silencing. Moreover, ANXA9 overexpression reversed the inhibitory impacts of SULT2B1 silencing on the proliferative, migrative, invasive, and apoptotic capabilities of SKOV3 cells.

CONCLUSION

In summary, SULT2B1 silencing repressed OC progression by targeting ANXA9.

An integrated investigation of sulfotransferases (SULTs) in hepatocellular carcinoma and identification of the role of SULT2A1 on stemness

The cytosolic sulfotransferases (SULTs) are phase II conjugating enzymes, which are widely expressed in the liver and mainly mediate the sulfation of numerous xenobiotics and endogenous compounds. However, the role of various SULTs genes has not been reported in hepatocellular carcinoma (HCC). This study aims to analyze the expression and potential functional roles of SULTs genes in HCC and to identify the role of SULT2A1 in HCC stemness as well as the possible mechanism. We found that all of the 12 SULTs genes were differentially expressed in HCC. Moreover, clinicopathological features and survival rates were also investigated. Multivariate regression analysis showed that SULT2A1 and SULT1C2 could be used as independent prognostic factors in HCC. SULT1C4, SULT1E1, and SULT2A1 were significantly associated with immune infiltration. SULT2A1 deficiency in HCC promoted chemotherapy resistance and stemness maintenance. Mechanistically, silencing of SULT2A1 activated the AKT signaling pathway, on the one hand, promoted the expression of downstream stemness gene c-Myc, on the other hand, facilitated the NRF2 expression to reduce the accumulation of ROS, and jointly increased HCC stemness. Moreover, knockdown NR1I3 was involved in the transcriptional regulation of SULT2A1 in stemness maintenance. In addition, SULT2A1 knockdown HCC cells promoted the proliferation and activation of hepatic stellate cells (HSCs), thereby exerting a potential stroma remodeling effect. Our study revealed the expression and role of SULTs genes in HCC and identified the contribution of SULT2A1 to the initiation and progression of HCC.

Sulfotransferase 2B1b, Sterol Sulfonation, and Disease

The primary function of human sulfotransferase 2B1b (SULT2B1b) is to sulfonate cholesterol and closely related sterols. SULT2B1b sterols perform a number of essential cellular functions. Many are signaling molecules whose activities are redefined by sulfonation-allosteric properties are switched "on" or "off," agonists are transformed into antagonists, and vice versa. Sterol sulfonation is tightly coupled to cholesterol homeostasis, and sulfonation imbalances are causally linked to cholesterol-related diseases including certain cancers, Alzheimer disease, and recessive X-linked ichthyosis-an orphan skin disease. Numerous studies link SULT2B1b activity to disease-relevant molecular processes. Here, these multifaceted processes are integrated into metabolic maps that highlight their interdependence and how their actions are regulated and coordinated by SULT2B1b oxysterol sulfonation. The maps help explain why SULT2B1b inhibition arrests the growth of certain cancers and make the novel prediction that SULT2B1b inhibition will suppress production of amyloid β (Aβ) plaques and tau fibrils while simultaneously stimulating Aβ plaque phagocytosis. SULT2B1b harbors a sterol-selective allosteric site whose structure is discussed as a template for creating inhibitors to regulate SULT2B1b and its associated biology. SIGNIFICANCE STATEMENT: Human sulfotransferase 2B1b (SULT2B1b) produces sterol-sulfate signaling molecules that maintain the homeostasis of otherwise pro-disease processes in cancer, Alzheimer disease, and X-linked ichthyosis-an orphan skin disease. The functions of sterol sulfates in each disease are considered and codified into metabolic maps that explain the interdependencies of the sterol-regulated networks and their coordinate regulation by SULT2B1b. The structure of the SULT2B1b sterol-sensing allosteric site is discussed as a means of controlling sterol sulfate biology.

NF-κB1 p50 stabilizes HIF-1α protein through suppression of ATG7-dependent autophagy

The function and underlying mechanisms of p50 in the regulation of protein expression is much less studied because of its lacking of transactivation domain. In this study, we discovered a novel function of p50 in its stabilization of hypoxia-inducible factor 1α (HIF-1α) protein under the condition of cells exposed to arsenic exposure. In p50-deficient (p50^-/-) cells, the HIF-1α protein expression was impaired upon arsenic exposure, and such defect could be rescued by reconstitutional expression of p50. Mechanistic study revealed that the inhibition of autophagy-related gene 7 (ATG7)-dependent autophagy was in charge of p50-mediated HIF-1α protein stabilization following arsenic exposure. Moreover, p50 deletion promoted nucleolin (NCL) protein translation to enhance ATG7 mRNA transcription via directly binding transcription factor Sp1 mRNA and increase its stability. We further discovered that p50-mediated miR-494 upregulation gave rise to the inhibition of p50-mediated NCL translation by interacting with its 3'-UTR. These novel findings provide a great insight into the understanding of biomedical significance of p50 protein in arsenite-associated disease development and therapy.

Antiproliferative effects of dried Moringa oleifera leaf extract on human Wharton's Jelly mesenchymal stem cells

Mesenchymal stem cells (MSCs) have seen an elevated use in clinical works like regenerative medicine. Its potential therapeutic properties increases when used in tandem with complementary agents like bio-based materials. Therefore, the present study is the first to investigate the cytotoxicity of a highly valued medicinal plant, Moringa oleifera, on human Wharton's Jelly mesenchymal stem cells (hWJMSCs) and its effects on the cells' gene expression when used as a pre-treatment agent in vitro. M. oleifera leaves (MOL) were dried and subjected to UHPLC-QTOF/MS analysis, revealing several major compounds like apigenin, kaempferol, and quercetin in the MOL, with various biological activities like antioxidant and anti-cancer properties. We then treated the hWJMSCs with MOL and noticed a dose-dependant inhibition on the cells' proliferation. RNA-sequencing was performed to explain the possible mechanism of action and revealed genes like PPP1R1C, SULT2B1, CDKN1A, mir-154 and CCNB1, whose expression patterns were closely associated with the negative cell cycle regulation and cell cycle arrest process. This is also evident from gene set enrichment analysis where the GO and KEGG terms for down-regulated pathways were closely related to the cell cycle regulation. The Ingenuity pathway analysis (IPA) software further predicted the significant activation of (p < 0.05, z-score > 2) of the G2/M DNA damage checkpoint regulation pathway. The present study suggests that MOL exhibits an antiproliferative effect on hWJMSCs via cell cycle arrest and apoptotic pathways. We believe that this study provides an important baseline reference for future works involving MOL's potential to accompany MSCs for clinical works. Future works can take advantage of the cell's strong anti-cancer gene expression found in this study, and evaluate our MOL treatment on various cancer cell lines.

Cholesterol sulfate alleviates ulcerative colitis by promoting cholesterol biosynthesis in colonic epithelial cells

Cholesterol sulfate, produced by hydroxysteroid sulfotransferase 2B1 (SULT2B1), is highly abundant in the intestine. Herein, we study the functional role and underlying intestinal epithelial repair mechanisms of cholesterol sulfate in ulcerative colitis. The levels of cholesterol and cholesterol sulfate, as well as the expression of Sult2b1 and genes involved in cholesterol biosynthesis, are significantly higher in inflamed tissues from patients with ulcerative colitis than in intestinal mucosa from healthy controls. Cholesterol sulfate in the gut and circulation is mainly catalyzed by intestinal epithelial SULT2B1. Specific deletion of the Sult2b1 gene in the intestinal epithelial cells aggravates dextran sulfate sodium-induced colitis; however, dietary supplementation with cholesterol sulfate ameliorates this effect in acute and chronic ulcerative colitis in mice. Cholesterol sulfate promotes cholesterol biosynthesis by binding to Niemann-Pick type C2 protein and activating sterol regulatory element binding protein 2 in colonic epithelial cells, thereby alleviates ulcerative colitis. In conclusion, cholesterol sulfate contributes to the healing of the mucosal barrier and exhibits therapeutic efficacy against ulcerative colitis in mice.

New treatment strategies are required for ulcerative colitis. Here the authors show in mouse models that cholesterol sulfate, an endogenous active cholesterol derivative, contributes to the healing of the mucosal barrier by promoting cholesterol biosynthesis in colonic epithelial cells and exhibits therapeutic efficacy against ulcerative colitis.

Characterization of the mechanism of Scutellaria baicalensis on reversing radio-resistance in colorectal cancer

Scutellaria baicalensis (SB) has been shown to improve the therapeutic effects of colorectal cancer (CRC) and perform well for reversing radio-resistance in different cancers. However, its potential function and mechanism related to radio-resistance in CRC has not been explored. A radio-resistant human CRC cell line (HCT116R) was applied. A network pharmacological analysis was performed to reveal the potential mechanism of SB for reversing radio-resistance in CRC, and computational pathological analysis was applied to indicate the clinicopathological significance of the key targets. Then, our hypothesis was further verified by molecular docking. The network pharmacology analysis showed that wogonin is the key compound of SB for reversing the radio-resistance of CRC. A Kyoto Encyclopedia of Genes and Genomes analysis showed that the genes for SB that reverse radio-resistance in CRC are mainly involved in steroid hormone biosynthesis. An enrichment analysis pointed out that Sulfotransferase family 2B member 1 (SULT2B1) is a potentially vital gene. SULT2B1 was demonstrated as being highly expressed in CRC and upregulated in radio-resistant rectal tissues or cell lines. A CCK-8 and clone formation test showed that the viability and clone formation ability of HCT116R were significantly decreased by wogonin combined with radiotherapy, compared to radiotherapy alone. By contrast, flow cytometry revealed that the apoptosis of HCT116R was significantly increased when wogonin treatment combined with radiotherapy, compared with radiotherapy alone. Molecular docking verification indicated that SULT2B1 and wogonin have a good binding ability. Taken together, SULT2B1 may be the potential drug target in treating radio-resistant CRC. Wogonin may be the core compound of SB for reversing radio-resistance in CRC by targeting SULT2B1.

Model Cell Lines and Tissues of Different HGSOC Subtypes Differ in Local Estrogen Biosynthesis

Simple Summary

Ovarian cancer (OC) comprises a heterogeneous group of hormone-dependent diseases with very high mortality. Estrogens have been shown to promote the progression of OC; however, their exact role in OC subtypes remains unknown. Here, we investigated the local estrogen biosynthesis in OC. We performed targeted transcriptomics and estrogen metabolism analyses in high-grade serous OC (HGSOC) cell lines that differed in chemoresistance status and compared these data with publicly available transcriptome and proteome data for HGSOC tissues. In HGSOC cells, estrogen metabolism decreased with increasing chemoresistance. In highly chemoresistant cells and platinum-resistant HGSOC tissues, HSD17B14 expression was increased. Proteome data showed differential levels of HSD17B10, SULT1E1, CYP1B1, and NQO1 between the four HGSOC subtypes. Our results confirm that estrogen biosynthesis differs between different HGSOC cell models and possibly between different HGSOC subtypes. Such differentially expressed enzymes have potential as targets in the search of new treatment options.

Abstract

Ovarian cancer (OC) is highly lethal and heterogeneous. Several hormones are involved in OC etiology including estrogens; however, their role in OC is not completely understood. Here, we performed targeted transcriptomics and estrogen metabolism analyses in high-grade serous OC (HGSOC), OVSAHO, Kuramochi, COV632, and immortalized normal ovarian epithelial HIO-80 cells. We compared these data with public transcriptome and proteome data for the HGSOC tissues. In all model systems, high steroid sulfatase expression and weak/undetected aromatase (CYP19A1) expression indicated the formation of estrogens from the precursor estrone-sulfate (E1-S). In OC cells, the metabolism of E1-S to estradiol was the highest in OVSAHO, followed by Kuramochi and COV362 cells, and decreased with increasing chemoresistance. In addition, higher HSD17B14 and CYP1A2 expressions were observed in highly chemoresistant COV362 cells and platinum-resistant tissues compared to those in HIO-80 cells and platinum-sensitive tissues. The HGSOC cell models differed in HSD17B10, CYP1B1, and NQO1 expression. Proteomic data also showed different levels of HSD17B10, CYP1B1, NQO1, and SULT1E1 between the four HGSOC subtypes. These results suggest that different HGSOC subtypes form different levels of estrogens and their metabolites and that the estrogen-biosynthesis-associated targets should be further studied for the development of personalized treatment.

27-Hydroxycholesterol promotes metastasis by SULT2A1-dependent alteration in hepatocellular carcinoma

Oxysterol metabolism plays an important role in the initiation and development of various tumors. However, little is known that the metabolic alternation can promote the metastasis of hepatocellular carcinoma (HCC). In this study, we identify the sulfotransferase family 2A member 1 (SULT2A1) to 27‐hydroxycholesterol (27‐OHC) metabolic axis as playing a critical role in HCC metastasis. The level of 27‐OHC closely corresponded with HCC metastasis instead of proliferation in vitro and in vivo. Also, the expression of SULT2A1 is extremely downregulated in human HCC tissues and is correlated with poor prognosis and tumor metastasis. Gain‐ and loss‐of‐function studies reveal that SULT2A1 suppresses the metastasis of HCC by regulating the level of 27‐OHC. Further mechanistic studies indicated that SULT2A1‐dependent alternation of 27‐OHC activates the nuclear factor‐κB signaling pathway and promotes HCC metastasis by enhancing Twist1 expression and epithelial–mesenchymal transition. In conclusion, our findings indicate the relationship between the metabolism of 27‐OHC and the metastasis of HCC. Moreover, SULT2A1 could act as a potential prognostic biomarker and a therapeutic target for preventing HCC metastasis.

The promoter hypermethylation of SULT2B1 accelerates esophagus tumorigenesis via downregulated PER1

Background

Esophageal cancer is currently the eighth most common tumor in the world and a leading cause of cancer death. SULT2B1 plays crucial roles in tumorigenesis. The purpose of this study is to explore the role of SULT2B1 in esophageal squamous cell carcinoma (ESCC).

Methods

The expression of SULT2B1 and its clinicopathological characteristics were evaluated in ESCC cohorts. Bisulfite genomic sequencing and methylation specific PCR were used to detect the promoter hypermethylation of the SULT2B1 gene. The effects of SULT2B1 on the biological characters of ESCC cells were identified on functional assays. Subcutaneous xenograft models revealed the role of SULT2B1 in vivo with tumor growth. RNA‐Seq analysis and qRT‐PCR were performed to recognize the targeted effect of SULT2B1 on PER1.

Results

SULT2B1 was not expressed or at a low level in most patients with ESCC or in ESCC cell lines, and this was accompanied by poor clinical prognosis. Furthermore, the downregulation of SULT2B1 occurred in promoter hypermethylation. According to the functional results, overexpression of SULT2B1 could inhibit tumoral proliferation in vitro and retard tumor growth in vivo, whereas SULT2B1 knockdown could accelerate ESCC progression. Mechanistically, SULT2B1 targeted PER1 at the mRNA level during post‐transcriptional regulation. Finally, PER1 was verified as a suppressor and poor‐prognosis factor in ESCC.

Conclusions

SULT2B1 loss is a consequence owing to its ability to promote hypermethylation. In addition, it serves as a suppressor and poor‐prognosis factor because of the post‐transcriptional regulation of PER1 in ESCC.

Verteporfin Promotes the Apoptosis and Inhibits the Proliferation, Migration, and Invasion of Cervical Cancer Cells by Downregulating SULT2B1 Expression

Background

Cervical cancer threatens women’s health worldwide. Verteporfin (VP), a small-molecule YAP1 inhibitor, inhibits cancer cell growth. This study investigated whether VP could inhibit the proliferation and promote the apoptosis of cervical cancer cells by decreasing SULT2B1 expression.

Material/Methods

Normal and cancerous cervical cell proliferation after VP treatment was detected by CCK-8 assay. HeLa cell migration, invasion, and apoptosis after VP treatment and transfection were analyzed by wound healing assay, transwell assay, and TUNEL assay, respectively. The expression of related proteins was determined by western blot analysis. Western blot and RT-qPCR analysis detected mRNA and protein expression of SULT2B1.

Results

Different VP concentrations (0.5, 1, 2, and 5 μM) inhibited the viability of HeLa cells and had no obvious effect on H8 cells. Therefore, 5 μM VP was selected for subsequent experiments. VP inhibited the proliferation, migration, and invasion of HeLa cells and promoted their apoptosis. Bcl-2 expression decreased, and expression of Bax, caspase-3, and caspase-9 in VP-treated HeLa cells increased. SULT2B1 expression increased in cervical cancer cells compared with normal cervical cells. Furthermore, SULT2B1 expression increased in HeLa cells and VP suppressed SULT2B1 expression. SULT2B1 overexpression reduced the inhibiting effect of VP on the proliferation, migration, and apoptosis of HeLa cells, and reduced VP effect on apoptosis of HeLa cells. SULT2B1 overexpression upregulated the Bcl-2 expression and downregulated the expression of Bax, caspase-3, and caspase-9 in VP-treated HeLa cells.

Conclusions

VP inhibited the proliferation, migration, and invasion and promoted apoptosis of cervical cancer cells by decreasing SULT2B1 expression.

The Role of Sulfotransferases in Liver Diseases

The cytosolic sulfotransferases (SULTs) are phase II conjugating enzymes that catalyze the transfer of a sulfonate group from the universal sulfate donor 3'-phosphoadenosine-5'-phosphosulfate to a nucleophilic group of their substrates to generate hydrophilic products. Sulfation has a major effect on the chemical and functional homeostasis of substrate chemicals. SULTs are widely expressed in metabolically active or hormonally responsive tissues, including the liver and many extrahepatic tissues. The expression of SULTs exhibits isoform-, tissue-, sex-, and development-specific regulations. SULTs display a broad range of substrates including xenobiotics and endobiotics. The expression of SULTs has been shown to be transcriptionally regulated by members of the nuclear receptor superfamily, such as the peroxisome proliferator-activated receptors, pregnane X receptor, constitutive androstane receptor, vitamin D receptor, liver X receptors, farnesoid X receptor, retinoid-related orphan receptors, estrogen-related receptors, and hepatocyte nuclear factor 4α These nuclear receptors can be activated by numerous xenobiotics and endobiotics, such as fatty acids, bile acids, and oxysterols, many of which are substrates of SULTs. Due to their metabolism of xenobiotics and endobiotics, SULTs and their regulations are implicated in the pathogenesis of many diseases. This review is aimed to summarize the central role of major SULTs, including the SULT1 and SULT2 subfamilies, in the pathophysiology of liver and liver-related diseases. SIGNIFICANCE STATEMENT: Sulfotransferases (SULTs) are indispensable in the homeostasis of xenobiotics and endobiotics. Knowing SULTs and their regulations are implicated in human diseases, it is hoped that genetic or pharmacological manipulations of the expression and/or activity of SULTs can be used to affect the clinical outcome of diseases.

Integration of IgA and IgG Autoantigens Improves Performance of Biomarker Panels for Early Diagnosis of Lung Cancer

Lung cancer (LC) remains the leading cause of mortality from malignant tumors worldwide. In our previous study, we surveyed both IgG and IgM-bound serological biomarkers and validated a panel of IgG-bound autoantigens for early LC diagnosis with 50% sensitivity at 90% specificity. To further improve the performance of these serological biomarkers, we surveyed HuProt arrays, comprised of 20,240 human proteins, for IgA-bound autoantigens because IgAs are a major immunoglobulin isotype in the lung. Integrating with IgG-bound autoantigens, we discovered and validated a combined biomarker panel using ELISA-format tests. Specifically, in Phase I, we obtained IgA-based autoimmune profiles of 69 early stage LC patients, 30 healthy subjects and 25 patients with lung benign lesions (LBL) on HuProt arrays and identified 28 proteins as candidate autoantigens that were significantly associated with early stage LC. In Phase II, we re-purified the autoantigens and converted them into an ELISA-format testing to profile an additional large cohort, comprised of 136 early stage LC patients, 58 healthy individuals, and 29 LBL patients. Integration of IgG autoimmune profiles allowed us to identify and validate a biomarker panel of three IgA autoantigens (i.e. BCL7A, and TRIM33 and MTERF4) and three IgG autoantigens (i.e. CTAG1A, DDX4 and MAGEC2) for diagnosis of early stage LC with 73.5% sensitivity at >85% specificity. In Phase III, the performance of this biomarker panel was confirmed with an independent cohort, comprised of 88 early stage LC patients, 18 LBL patients, and 36 healthy subjects. Finally, a blind test on 178 serum samples was conducted to confirm the performance of the biomarker panel. In summary, this study demonstrates for the first time that an integrated panel of IgA/IgG autoantigens can serve as valuable biomarkers to further improve the performance of early diagnosis of LC.

Hydroxysteroid sulfotransferase 2B1 affects gastric epithelial function and carcinogenesis induced by a carcinogenic agent

Background

A healthy gastric mucosal epithelium exhibits tumor-suppressive properties. Gastric epithelial cell dysfunction contributes to gastric cancer development. Oxysterols provided from food or cholesterol oxidation in the gastric epithelium may be further sulfated by hydroxysteroid sulfotransferase 2B1 (SULT2B1), which is highly abundant in the gastric epithelium. However, the effects of SULT2B1 on gastric epithelial function and gastric carcinogenesis are unclear.

Methods

A mouse gastric tumor model was established using carcinogenic agent 3-methylcholanthrene (3-MCA). A SULT2B1 deletion (SULT2B1^−/−) human gastric epithelial line GES-1 was constructed by CRISPR/CAS9 genome editing system.

Results

The gastric tumor incidence was higher in the SULT2B1^−/− mice than in the wild-type (WT) mice. In gastric epithelial cells, adenovirus-mediated SULT2B1b overexpression reduced the levels of oxysterols, such as 24(R/S),25-epoxycholesterol (24(R/S),25-EC) and 27-hydroxycholesterol (27HC). This condition also increased PI3K/AKT signaling to promote gastric epithelial cell proliferation, epithelization, and epithelial development. However, SULT2B1 deletion or SULT2B1 knockdown suppressed PI3K/AKT signaling, epithelial cell epithelization, and wound healing and induced gastric epithelial cell malignant transition upon 3-MCA induction.

Conclusions

The abundant SULT2B1 expression in normal gastric epithelium might maintain epithelial function via the PI3K/AKT signaling pathway and suppress gastric carcinogenesis induced by a carcinogenic agent.

Effect of SULT2B1 genetic polymorphisms on the sulfation of dehydroepiandrosterone and pregnenolone by SULT2B1b allozymes

Pregnenolone and dehydroepiandrosterone (DHEA) are hydroxysteroids that serve as biosynthetic precursors for steroid hormones in human body. SULT2B1b has been reported to be critically involved in the sulfation of pregnenolone and DHEA, particularly in the sex steroid-responsive tissues. The current study was designed to investigate the impact of the genetic polymorphisms of SULT2B1 on the sulfation of DHEA and pregnenolone by SULT2B1b allozymes. Ten SULT2B1b allozymes previously prepared were shown to exhibit differential sulfating activities toward DHEA and pregnenolone in comparison to the wild-type enzyme. Kinetic studies revealed further significant changes in their substrate-binding affinity and catalytic activity toward DHEA and pregnenolone. Taken together, these results indicated clearly a profound effect of SULT2B1 genetic polymorphisms on the sulfating activity of SULT2B1b allozymes toward DHEA and pregnenolone, which may have implications in inter-individual variations in the homeostasis of these two important steroid precursors.

An Unexpected Role of Cholesterol Sulfotransferase and its Regulation in Sensitizing Mice to Acetaminophen-Induced Liver Injury

Overdose of acetaminophen (APAP) is the leading cause of acute liver failure (ALF) in the United States. The sulfotransferase-mediated sulfation of APAP is widely believed to be a protective mechanism to attenuate the hepatotoxicity of APAP. The cholesterol sulfotransferase SULT2B1b is best known for its activity in catalyzing the sulfoconjugation of cholesterol to synthesize cholesterol sulfate. SULT2B1b can be transcriptionally and positively regulated by the hepatic nuclear factor 4α (HNF4α). In this study, we uncovered an unexpected role for SULT2B1b in APAP toxicity. Hepatic overexpression of SULT2B1b sensitized mice to APAP-induced liver injury, whereas ablation of the Sult2B1b gene in mice conferred resistance to the APAP hepatotoxicity. Consistent with the notion that Sult2B1b is a transcriptional target of HNF4α, overexpression of HNF4α sensitized mice or primary hepatocytes to APAP-induced hepatotoxicity in a Sult2B1b-dependent manner. We conclude that the HNF4α-SULT2B1b axis has a unique role in APAP-induced acute liver injury, and SULT2B1b induction might be a risk factor for APAP hepatotoxicity.

On the role of genetic polymorphisms in the sulfation of cholesterol by human cytosolic sulphotransferase SULT2B1b

Sulphated cholesterol, like its unsulphated counterpart, is known to be biologically active and serves a myriad of biochemical/physiological functions. Of the 13 human cytosolic sulphotransferases (SULTs), SULT2B1b has been reported as the main enzyme responsible for the sulphation of cholesterol. As such, SULT2B1b may play the role as a key regulator of cholesterol metabolism. Variations in the sulphating activity of SULT2B1b may affect the sulphation of cholesterol and, consequently, the related physiological events. This study was designed to evaluate the impact of the genetic polymorphisms on the sulphation of cholesterol by SULT2B1b. Ten recombinant SULT2B1b allozymes were generated, expressed, and purified. Purified SULT2B1b allozymes were shown to display differential cholesterol-sulphating activities, compared with the wild-type enzyme. Kinetic studies revealed further their distinct substrate affinity and catalytic efficiency toward cholesterol. These findings showed clearly the impact of genetic polymorphisms on the cholesterol-sulphating activity of SULT2B1b allozymes, which may underscore the differential metabolism of cholesterol in individuals with different SULT2B1b genotypes.

Association study of genetic variants in estrogen metabolic pathway genes and colorectal cancer risk and survival

Although studies have investigated the association of genetic variants and the abnormal expression of estrogen-related genes with colorectal cancer risk, the evidence remains inconsistent. We clarified the relationship of genetic variants in estrogen metabolic pathway genes with colorectal cancer risk and survival. A case-control study was performed to assess the association of single-nucleotide polymorphisms (SNPs) in ten candidate genes with colorectal cancer risk in a Chinese population. A logistic regression model and Cox regression model were used to calculate SNP effects on colorectal cancer susceptibility and survival, respectively. Expression quantitative trait loci (eQTL) analysis was conducted using the Genotype-Tissue Expression (GTEx) project dataset. The sequence kernel association test (SKAT) was used to perform gene-set analysis. Colorectal cancer risk and rs3760806 in SULT2B1 were significantly associated in both genders [male: OR = 1.38 (1.15-1.66); female: OR = 1.38 (1.13-1.68)]. Two SNPs in SULT1E1 were related to progression-free survival (PFS) [rs1238574: HR = 1.24 (1.02-1.50), P = 2.79 × 10^-2; rs3822172: HR = 1.30 (1.07-1.57), P = 8.44 × 10^-3] and overall survival (OS) [rs1238574: HR = 1.51 (1.16-1.97), P = 2.30 × 10^-3; rs3822172: HR = 1.53 (1.67-2.00), P = 2.03 × 10^-3]. Moreover, rs3760806 was an eQTL for SULT2B1 in colon samples (transverse: P = 3.6 × 10^-3; sigmoid: P = 1.0 × 10^-3). SULT2B1 expression was significantly higher in colorectal tumor tissues than in normal tissues in the Cancer Genome Atlas (TCGA) database (P < 1.0 × 10^-4). Our results indicated that SNPs in estrogen metabolic pathway genes confer colorectal cancer susceptibility and survival.

Regulation of Cholesterol Sulfotransferase SULT2B1b by Hepatocyte Nuclear Factor 4α Constitutes a Negative Feedback Control of Hepatic Gluconeogenesis

The cholesterol sulfotransferase SULT2B1b converts cholesterol to cholesterol sulfate (CS). We previously reported that SULT2B1b inhibits hepatic gluconeogenesis by antagonizing the gluconeogenic activity of hepatocyte nuclear factor 4α (HNF4α). In this study, we showed that the SULT2B1b gene is a transcriptional target of HNF4α, which led to our hypothesis that the induction of SULT2B1b by HNF4α represents a negative feedback to limit the gluconeogenic activity of HNF4α. Indeed, downregulation of Sult2B1b enhanced the gluconeogenic activity of HNF4α, which may have been accounted for by the increased acetylation of HNF4α as a result of decreased expression of the HNF4α deacetylase sirtuin 1 (Sirt1). The expression of Sult2B1b was also induced by HNF4α upon fasting, and the Sult2B1b null (Sult2B1b-/-) mice showed increased gluconeogenic gene expression and an elevated fasting glucose level, suggesting that SULT2B1b also plays a restrictive role in HNF4α-mediated fasting-responsive gluconeogenesis. We also developed thiocholesterol, a hydrolysis-resistant derivative of CS, which showed superior activity to that of the native CS in inhibiting gluconeogenesis and improving insulin sensitivity in high-fat-diet-induced diabetic mice. We conclude that the HNF4α-SULT2B1b-CS axis represents a key endogenous mechanism to prevent uncontrolled gluconeogenesis. Thiocholesterol may be used as a therapeutic agent to manage hyperglycemia.

Investigating piwi-interacting RNA regulome in human neuroblastoma

Remarkable attempts have been exercised in recent years using high-throughput technologies to identify and decipher the functions of piRNAs in various abnormalities like cancer. However, piRNAs in the oncogenesis of neuroblastoma (NB) has not been reported yet even after their illustrated roles in neurological processes. Therefore, we investigated the piRNA transcriptome in IMR-32 and SH-SY-5Y NB cell lines by employing high-throughput next-generation sequencing after confirming the expression of three associated PIWILs both at mRNAs and protein level by qRT-PCR and immunofluroscence, respectively. We identified a common pool of 525 piRNAs of 26-32 nts long expressed in both the cell lines. The possible functions of these piRNAs were charted by predicting their targeting on retrotransposon-containing 1769 mRNAs differentially expressed in 39 NB cell lines followed by network and pathway analysis. The analysis revealed that majority of the target binding sites in NB fall within retrotransposons residing within the 3'UTR of target mRNA transcripts like miRNA-targets. Further, we validated the expression of key piRNAs and their target genes enriched in cancer-related networks, pathways and biological processes which are hypothesized to play crucial roles in neoplastic events of NB. We believe that the evidence of piRNAs in human NB and their possible contribution to its pathogenesis reported in this work will open up new exciting possibilities for piRNA-mediated therapeutics for this malignancy.

Metabolomics guided pathway analysis reveals link between cancer metastasis, cholesterol sulfate, and phospholipids

Background

Cancer cells that enter the metastatic cascade require traits that allow them to survive within the circulation and colonize distant organ sites. As disseminating cancer cells adapt to their changing microenvironments, they also modify their metabolism and metabolite production.

Methods

A mouse xenograft model of spontaneous tumor metastasis was used to determine the metabolic rewiring that occurs between primary cancers and their metastases. An “autonomous” mass spectrometry-based untargeted metabolomic workflow with integrative metabolic pathway analysis revealed a number of differentially regulated metabolites in primary mammary fat pad (MFP) tumors compared to microdissected paired lung metastases. The study was further extended to analyze metabolites in paired normal tissues which determined the potential influence of metabolites from the microenvironment.

Results

Metabolomic analysis revealed that multiple metabolites were increased in metastases, including cholesterol sulfate and phospholipids (phosphatidylglycerols and phosphatidylethanolamine). Metabolite analysis of normal lung tissue in the mouse model also revealed increased levels of these metabolites compared to tissues from normal MFP and primary MFP tumors, indicating potential extracellular uptake by cancer cells in lung metastases. These results indicate a potential functional importance of cholesterol sulfate and phospholipids in propagating metastasis. In addition, metabolites involved in DNA/RNA synthesis and the TCA cycle were decreased in lung metastases compared to primary MFP tumors.

Conclusions

Using an integrated metabolomic workflow, this study identified a link between cholesterol sulfate and phospholipids, metabolic characteristics of the metastatic niche, and the capacity of tumor cells to colonize distant sites.

Electronic supplementary material

The online version of this article (10.1186/s40170-017-0171-2) contains supplementary material, which is available to authorized users.

Cholesterol Sulfonation Enzyme, SULT2B1b, Modulates AR and Cell Growth Properties in Prostate Cancer

Cholesterol accumulates in prostate lesions and has been linked to prostate cancer incidence and progression. However, how accumulated cholesterol contributes to prostate cancer development and progression is not completely understood. Cholesterol sulfate (CS), the primary sulfonation product of cholesterol sulfotransferase (SULT2B1b), accumulates in human prostate adenocarcinoma and precancerous prostatic intraepithelial neoplasia (PIN) lesions compared with normal regions of the same tissue sample. Given the enhanced accumulation of CS in these lesions, it was hypothesized that SULT2B1b-mediated production of CS provides a growth advantage to these cells. To address this, prostate cancer cells with RNAi-mediated knockdown (KD) of SULT2B1b were used to assess the impact on cell growth and survival. SULT2B1b is expressed and functional in a variety of prostate cells, and the data demonstrate that SULT2B1b KD, in LNCaP and other androgen-responsive (VCaP and C4-2) cells, results in decreased cell growth/viability and induces cell death. SULT2B1b KD also decreases androgen receptor (AR) activity and expression at mRNA and protein levels. While AR overexpression has no impact on SULT2B1b KD-mediated cell death, the addition of exogenous androgen is able to partially rescue the growth inhibition induced by SULT2B1b KD in LNCaP cells. These results suggest that SULT2B1b positively regulates the AR either through alterations in ligand availability or by interaction with critical coregulators that influence AR activity.

IMPLICATIONS

These findings provide evidence that SULT2B1b is a novel regulator of AR activity and cell growth in prostate cancer and should be further investigated for therapeutic potential. Mol Cancer Res; 14(9); 776-86. ©2016 AACR.

Upregulation of hydroxysteroid sulfotransferase 2B1b promotes hepatic oval cell proliferation by modulating oxysterol-induced LXR activation in a mouse model of liver injury

Hydroxysteroid sulfotransferase 2B1b (SULT2B1b) sulfates cholesterol and oxysterols. Hepatic oval cells (HOCs), thought to be progenitor cells, can be triggered in chemically injured livers. The present study focused on the role of SULT2B1b in HOC proliferation after liver injury. Our experiments revealed that the expression of SULT2B1b was increased dramatically in a chemical-induced liver injury model, mainly in HOCs. Upon challenge with a hepatotoxic diet containing 0.1 % 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC), SULT2B1^-/- mice presented alleviated liver injury and less HOC proliferation compared with wild-type (WT) mice, and these findings were verified by serum analysis, histopathology, immunofluorescence staining, RNA-seq, and Western blotting. HOCs derived from SULT2B1^-/- mice showed lower proliferative capability than those from WT mice. SULT2B1b overexpression promoted growth of the WB-F344 hepatic oval cell line, whereas SULT2B1b knockdown inhibited growth of these cells. The IL-6/STAT3 signaling pathway also was promoted by SULT2B1b. Liquid chromatography and mass spectrometry indicated that the levels of 22-hydroxycholesterol, 25-hydroxycholesterol, and 24,25-epoxycholesterol were higher in the DDC-injured livers of SULT2B1^-/- mice than in livers of WT mice. The above oxysterols are physiological ligands of liver X receptors (LXRs), and SULT2B1b suppressed oxysterol-induced LXR activation. Additional in vivo and in vitro experiments demonstrated that LXR activation could inhibit HOC proliferation and the IL-6/STAT3 signaling pathway, and these effects could be reversed by SULT2B1b. Our data indicate that upregulation of SULT2B1b might promote HOC proliferation and aggravate liver injury via the suppression of oxysterol-induced LXR activation in chemically induced mouse liver injury.

Microarray Analysis of Differentially-Expressed Genes Encoding CYP450 and Phase II Drug Metabolizing Enzymes in Psoriasis and Melanoma

Cytochrome P450 drug metabolizing enzymes are implicated in personalized medicine for two main reasons. First, inter-individual variability in CYP3A4 expression is a confounding factor during cancer treatment. Second, inhibition or induction of CYP3A4 can trigger adverse drug–drug interactions. However, inflammation can downregulate CYP3A4 and other drug metabolizing enzymes and lead to altered metabolism of drugs and essential vitamins and lipids. Little is known about effects of inflammation on expression of CYP450 genes controlling drug metabolism in the skin. Therefore, we analyzed seven published microarray datasets, and identified differentially-expressed genes in two inflammatory skin diseases (melanoma and psoriasis). We observed opposite patterns of expression of genes regulating metabolism of specific vitamins and lipids in psoriasis and melanoma samples. Thus, genes controlling the turnover of vitamin D (CYP27B1, CYP24A1), vitamin A (ALDH1A3, AKR1B10), and cholesterol (CYP7B1), were up-regulated in psoriasis, whereas melanomas showed downregulation of genes regulating turnover of vitamin A (AKR1C3), and cholesterol (CYP39A1). Genes controlling abnormal keratinocyte differentiation and epidermal barrier function (CYP4F22, SULT2B1) were up-regulated in psoriasis. The up-regulated CYP24A1, CYP4F22, SULT2B1, and CYP7B1 genes are potential drug targets in psoriatic skin. Both disease samples showed diminished drug metabolizing capacity due to downregulation of the CYP1B1 and CYP3A5 genes. However, melanomas showed greater loss of drug metabolizing capacity due to downregulation of the CYP3A4 gene.

Overexpression of SULT2B1b is an independent prognostic indicator and promotes cell growth and invasion in colorectal carcinoma

Aberrant expression of cytosolic sulfotransferase 2B1b (SULT2B1b) has been reported in several human malignancies. However, the expression pattern and clinical significance of SULT2B1b in colorectal carcinoma (CRC) remains unknown. Real-time quantitative PCR, western blot, and immunohistochemistry analyses were used to determine SULT2B1b expression in CRC clinical samples and CRC-derived cell lines. Kaplan-Meier and Cox proportional regression analyses were used to evaluate the association between SULT2B1b expression and patient survival in two independent cohorts of 485 patients with CRC. Gain- and loss-of-function approaches were employed to investigate the role of SULT2B1b in regulation of CRC cell growth and invasion. We found that SULT2B1b expression was frequently upregulated in CRC clinical samples and CRC-derived cell lines and was significantly correlated with lymph node metastasis and TNM stage in both the training and validation cohorts. Patients with higher intratumoral SULT2B1b expression had a significantly shorter disease-specific survival (DSS) and disease-free survival (DFS) than those with lower expression. Importantly, increased expression of SULT2B1b significantly predicted poor DSS and DFS and was an independent unfavorable prognostic indicator for stage II patients in both cohorts. Functional studies revealed that overexpression of SULT2B1b promoted CRC cell growth and invasion in vitro. Conversely, knockdown of SULT2B1b inhibited these processes. In conclusion, our findings suggest that SULT2B1b expression correlates with disease progression and metastasis and may serve as a novel prognostic biomarker and potential therapeutic target for patients with CRC.

Dysregulation of male sex hormones in chronic hepatitis C patients

Chronic hepatitis C (HCV) infection is a serious problem all over the world and has a special importance in Egypt, where the prevalence of infection is 14.7% of population. In males, HCV is associated with sexual dysfunction and changes in the semen parameters. This study aimed at estimation of a panel of the most important related hormones in the serum of patients and illustration of their correlation to the routine laboratory investigations. The four studied hormones showed alteration in the patients in comparison with the controls. While androstenedione, prolactin and testosterone were significantly increased in patients, dehydroepiandrosterone sulphate was decreased. These changes in the hormones were not related to the liver functions, pathological grade or even viral load. We hypothesised a model of how HCV can induce these hormonal changes and recommended to add these hormones to the follow-up panel of male patients with HCV.