PGF2alpha Inhibits 20alpha-HSD Expression by Suppressing CK1alpha-induced ERK and SP1 Activation in the Corpus Luteum of Pregnant Mice.

Prostaglandin F2α (PGF2α) is a luteolytic hormone that promotes parturition in mammals at the end of pregnancy by reducing progesterone secretion from the corpus luteum (CL). In rodents and primates, PGF2α rapidly converts progesterone to 20α-hydroxyprogesterone (20α-OHP) by promoting 20α-hydroxysteroid dehydrogenase (20α-HSD) expression. However, the specific mechanism of 20α-HSD regulation by PGF2α remains unclear. Casein Kinase 1α (CK1α) is a CK1 family member that regulates a variety of physiological functions, including reproductive development. Here, we investigated the effects of CK1α on pregnancy in female mice. Our experiments showed that CK1α is expressed in mouse CL, and its inhibition enhanced progesterone metabolism, decreased progesterone levels, and affected mouse embryo implantation. Further, CK1α mediated the effect of PGF2α on 20α-HSD in mouse luteal cells in vitro. Our results are the first to show that CK1α affects the 20α-HSD mRNA level by affecting the ERK signalling pathway to regulate the expression of the transcription factor SP1. These findings improve our understanding of PGF2α regulation of 20α-HSD.

Porcine aldo-keto reductase 1C subfamily members AKR1C1 and AKR1C4: Substrate specificity, inhibitor sensitivity and activators.

Most members of the aldo-keto reductase (AKR) 1 C subfamily are hydroxysteroid dehydrogenases (HSDs). Similarly to humans, four genes for AKR1C proteins (AKR1C1-AKR1C4) have been identified in the pig, which is a suitable species for biomedical research model of human diseases and optimal organ donor for xenotransplantation. Previous study suggested that, among the porcine AKR1Cs, AKR1C1 and AKR1C4 play important roles in steroid hormone metabolism in the reproductive tissues; however, their biological functions are still unknown. Herein, we report the biochemical properties of the two recombinant enzymes. Kinetic and product analyses of steroid specificity indicated that AKR1C1 is a multi-specific reductase, which acts as 3α-HSD for 3-keto-5ß-dihydro-C19/C21-steroids, 3ß-HSD for 3-keto-5α-dihydro-C19-steroids including androstenone, 17ß-HSD for 17-keto-C19-steroids including estrone, and 20α-HSD for progesterone, showing Km values of 0.5-11 µM. By contrast, AKR1C4 exhibited only 3α-HSD activity for 3-keto groups of 5α/ß-dihydro-C19-steroids, 5ß-dihydro-C21-steroids and bile acids (Km: 1.0-1.9 µM). AKR1C1 and AKR1C4 also showed broad substrate specificity for nonsteroidal carbonyl compounds including endogenous 4-oxo-2-nonenal, 4-hydroxy-nonenal, acrolein, isocaproaldehyde, farnesal, isatin and methylglyoxal, of which 4-oxo-2-nonenal was reduced with the lowest Km value of 0.9 µM. Moreover, AKR1C1 had the characteristic of reducing aliphatic ketones and all-trans-retinal. The enzymes were inhibited by flavonoids, synthetic estrogens, nonsteroidal anti-inflammatory drugs, triterpenoids and phenolphthalein, whereas only AKR1C4 was activated by bromosulfophthalein. These results suggest that AKR1C1 and AKR1C4 function as 3α/3ß/17ß/20α-HSD and 3α-HSD, respectively, in metabolism of steroid hormones and a sex pheromone androstenone, both of which also play roles in metabolism of nonsteroidal carbonyl compounds.

AKR1C1/2 inhibition by MPA sensitizes platinum resistant ovarian cancer towards carboplatin.

In recurrent epithelial ovarian cancer (EOC) most patients develop platinum-resistance. On molecular level the NRF2 pathway, a cellular defense mechanism against reactive oxygen species, is induced. In this study, we investigate AKR1C1/2, target of NRF2, in a well-established EOC collective by immunohistochemistry and in a panel of ovarian cancer cell lines including platinum-resistant clones. The therapeutic effect of carboplatin and MPA as monotherapy or in combination was assessed by functional assays, using OV90 and OV90cp cells. Molecular mechanisms of action of MPA were investigated by NRF2 silencing and AKR activity measurements. Immunohistochemical analysis revealed that AKR1C1/2 is a key player in the development of chemoresistance and an independent indicator for short PFS (23.5 vs. 49.6 months, p = 0.013). Inhibition of AKR1C1/2 by MPA led to a concentration- and time-dependent decline of OV90 viability and to an increased response to CP in vitro. By NRF2 silencing, however, the effects of MPA treatment were reduced. Concludingly, our data suggest that a combination therapy of carboplatin and MPA might be a promising therapeutic approach to increase response rates of EOC patients, which should be explored in clinical context.

Overview of human 20 alpha-hydroxysteroid dehydrogenase (AKR1C1): Functions, regulation, and structural insights of inhibitors.

Human aldo-keto reductase family 1C1 (AKR1C1) is an important enzyme involved in human hormone metabolism, which is mainly responsible for the metabolism of progesterone in the human body. AKR1C1 is highly expressed and has an important relationship with the occurrence and development of various diseases, especially some cancers related to hormone metabolism. Nowadays, many inhibitors against AKR1C1 have been discovered, including some synthetic compounds and natural products, which have certain inhibitory activity against AKR1C1 at the target level. Here we briefly reviewed the physiological and pathological functions of AKR1C1 and the relationship with the disease, and then summarized the development of AKR1C1 inhibitors, elucidated the interaction between inhibitors and AKR1C1 through molecular docking results and existing co-crystal structures. Finally, we discussed the design ideals of selective AKR1C1 inhibitors from the perspective of AKR1C1 structure, discussed the prospects of AKR1C1 in the treatment of human diseases in terms of biomarkers, pre-receptor regulation and single nucleotide polymorphisms, aiming to provide new ideas for drug research targeting AKR1C1.

Altered Steroidome in Women with Gestational Diabetes Mellitus: Focus on Neuroactive and Immunomodulatory Steroids from the 24th Week of Pregnancy to Labor.

Gestational diabetes mellitus (GDM) is a complication in pregnancy, but studies focused on the steroidome in patients with GDM are not available in the public domain. This article evaluates the steroidome in GDM+ and GDM- women and its changes from 24 weeks (± of gestation) to labor. The study included GDM+ (n = 44) and GDM- women (n = 33), in weeks 24-28, 30-36 of gestation and at labor and mixed umbilical blood after delivery. Steroidomic data (101 steroids quantified by GC-MS/MS) support the concept that the increasing diabetogenic effects with the approaching term are associated with mounting progesterone levels. The GDM+ group showed lower levels of testosterone (due to reduced AKR1C3 activity), estradiol (due to a shift from the HSD17B1 towards HSD17B2 activity), 7-oxygenated androgens (competing with cortisone for HSD11B1 and shifting the balance from diabetogenic cortisol towards the inactive cortisone), reduced activities of SRD5As, and CYP17A1 in the hydroxylase but higher CYP17A1 activity in the lyase step. With the approaching term, the authors found rising activities of CYP3A7, AKR1C1, CYP17A1 in its hydroxylase step, but a decline in its lyase step, rising conjugation of neuroinhibitory and pregnancy-stabilizing steroids and weakening AKR1D1 activity.

Steroid-converting enzymes in human adipose tissues and fat deposition with a focus on AKR1C enzymes.

Adipocytes express various enzymes, such as aldo-keto reductases (AKR1C), 11ß-hydroxysteroid dehydrogenase (11ß-HSD), aromatase, 5α-reductases, 3ß-HSD, and 17ß-HSDs involved in steroid hormone metabolism in adipose tissues. Increased activity of AKR1C enzymes and their expression in mature adipocytes might indicate the association of these enzymes with subcutaneous adipose tissue deposition. The inactivation of androgens by AKR1C enzymes increases adipogenesis and fat mass, particularly subcutaneous fat. AKR1C also causes reduction of estrone, a weak estrogen, to produce 17ß-estradiol, a potent estrogen and, in addition, it plays a role in progesterone metabolism. Functional impairments of adipose tissue and imbalance of steroid biosynthesis could lead to metabolic disturbances. In this review, we will focus on the enzymes involved in steroid metabolism and fat tissue deposition.

AKR1C1 alleviates LPS­induced ALI in mice by activating the JAK2/STAT3 signaling pathway.

Acute lung injury (ALI) is a respiratory tract disease characterized by increased alveolar/capillary permeability, lung inflammation and structural damage to lung tissues, which can progress and transform into acute respiratory distress syndrome (ARDS). Although there are several treatment strategies available to manage this condition, there is still no specific cure for ALI. Aldo­keto reductase family 1 member C1 (AKR1C1) is a member of the aldo­keto reductase superfamily, and is a well­known Nrf2 target gene and an oxidative stress gene. The aim of the present study was to investigate the effects of AKR1C1 on a lipopolysaccharide (LPS)­induced ALI model. After mice received LPS treatment, the mRNA expression levels of AKR1C1 in the bronchoalveolar lavage fluid and serum were measured using reverse transcription­quantitative PCR and its relationship with the inflammatory factors and malondialdehyde levels were determined using correlation analysis. Next, AKR1C1 was overexpressed or knocked out in mice, and subsequently ALI was induced in mice using LPS. The severity of ALI, oxidative stress and inflammation in the lungs were measured, and the potential involvement of the Janus kinase 2 (JAK2)/signal transduction activator of transcription 3 (STAT3) signaling pathway was assessed by measuring the changes of lung injury parameters after the agonists of JAK2/STAT3 pathway, including interleukin (IL)­6 and colivelin, were administrated to mice. The results revealed that AKR1C1 expression was decreased in the LPS­induced ALI mouse model. AKR1C1 expression was inversely correlated with serum tumor necrosis factor­α, IL­6 and malondialdehyde levels, and positively correlated with serum IL­10 levels. AKR1C1 overexpression significantly attenuated lung injury, as shown by the changes in Evans blue leakage in the lung, lung wet/dry weight ratio, PaO2/FIO2 ratio, survival rate of mice and histological lung changes. In addition, the JAK2/STAT3 signaling pathway was significantly deactivated by AKR1C1+/+. When AKR1C1+/+ mice were treated with JAK2/STAT3 agonists, the effects of AKR1C1 overexpression on lung injury and oxidative stress were abolished. In conclusion, AKR1C1 may protect against oxidative stress and serve as a negative regulator of inflammation in ALI/ARDS. In addition, the JAK2/STAT3 signaling pathway could participate in the protective effects of AKR1C1 against ALI.

Synthesis and evaluation of AKR1C inhibitory properties of A-ring halogenated oestrone derivatives.

Enzymes AKR1C regulate the action of oestrogens, androgens, and progesterone at the pre-receptor level and are also associated with chemo-resistance. The activities of these oestrone halides were investigated on recombinant AKR1C enzymes. The oestrone halides with halogen atoms at both C-2 and C-4 positions (13ß-, 13α-methyl-17-keto halogen derivatives) were the most potent inhibitors of AKR1C1. The lowest IC50 values were for the 13α-epimers 2_2I,4Br and 2_2I,4Cl (IC50, 0.7 µM, 0.8 µM, respectively), both of which selectively inhibited the AKR1C1 isoform. The 13α-methyl-17-keto halogen derivatives 2_2Br and 2_4Cl were the most potent inhibitors of AKR1C2 (IC50, 1.5 µM, 1.8 µM, respectively), with high selectivity for the AKR1C2 isoform. Compound 1_2Cl,4Cl showed the best AKR1C3 inhibition, and it also inhibited AKR1C1 (Ki: AKR1C1, 0.69 µM; AKR1C3, 1.43 µM). These data show that halogenated derivatives of oestrone represent a new class of potent and selective AKR1C inhibitors as lead compounds for further optimisations.

11-Ketotestosterone is a major androgen produced in porcine adrenal glands and testes.

Porcine steroid hormone profiles have some unique characteristics. We previously studied human and murine steroidogenesis using steroidogenic cells-derived from mesenchymal stem cells (MSCs). To investigate porcine steroidogenesis, we induced steroidogenic cells from porcine subcutaneous preadipocytes (PSPA cells), which originate from MSCs. Using cAMP, adenovirus-mediated introduction of steroidogenic factor-1 (SF-1)/adrenal 4-binding protein (Ad4BP) induced the differentiation of PSPA cells into sex steroid-producing cells. Introducing SF-1/Ad4BP also induced the aldo-keto reductase 1C1 (AKR1C1) gene. Porcine AKR1C1 had 17ß-hydroxysteroid dehydrogenase activity, which converts androstenedione and 11-ketoandrostenedione into testosterone (T) and 11-ketotestosteorne (11KT). Furthermore, differentiated cells expressed hydroxysteroid 11ß-dehydrogenase 2 (HSD11B2) and produced 11KT. HSD11B2 was expressed in testicular Leydig cells and the adrenal cortex. 11KT was present in the plasma of both immature male and female pigs, with slightly higher levels in the male pigs. T levels were much higher in the male pigs. It is noteworthy that in the female pigs, the 11KT levels were >10-fold higher than the T levels. However, castration altered the 11KT and T plasma profiles in the male pigs to near those of the females. 11KT induced endothelial nitric oxide synthase (eNOS) in porcine vascular endothelial cells. These results indicate that 11KT is produced in porcine adrenal glands and testes, and may regulate cardiovascular functions through eNOS expression.

AKR1C1 Contributes to Cervical Cancer Progression via Regulating TWIST1 Expression.

Cervical cancer (CC) is a common gynecological malignancy, accounting for 10% of all gynecological cancers. Recently, targeted therapy for CC has shown unprecedented advantages. To improve CC patients' prognosis, there are still urgent needs to develop more promising therapeutic targets. Aldo-keto reductase 1 family member C1 (AKR1C1) is a type of aldosterone reductase and plays a regulatory role in a variety of key metabolic pathways. Several studies indicated that AKR1C1 was highly expressed in a series of tumors, and participated in the progression of these tumors. However, the possible effects of AKR1C1 on CC progression remain unclear. Herein, we revealed AKR1C1 was highly expressed in human CC tissues and correlated with the clinical characteristics of patients with CC. AKR1C1 could regulate the proliferation and invasion of cervical cancer cells in vitro. Further experiments showed that AKR1C1 could regulate TWIST1 expression and AKT pathway. In summary, we confirmed the involvement of AKR1C1 in CC progression, and therefore AKR1C1 may have the potential to be a molecular target for CC treatment.

Use of AKR1C1 and TKTL1 in the Diagnosis of Low-grade Squamous Intraepithelial Lesions from Mexican Women.

BACKGROUND/AIM: To determine the differential protein profiles of cervical cancer cell lines in order to find potential targets that can be used as biomarkers in low-grade squamous intraepithelial lesions (LSIL) diagnosis. MATERIALS AND METHODS: Proteomic analysis was performed on cervical cancer cell lines by 2D electrophoresis and liquid chromatography-mass spectrometry. Biomarker validation was performed in histological samples by immunofluorescence. RESULTS: Aldo-keto reductase C1 (AKR1C1) and transketolase-like 1 (TKTL1) proteins were selected as biomarkers and their expression was increased in samples with LSIL diagnosis. TKTL1 in combination with AKR1C1 increased sensitivity and specificity to 75% and 66%, respectively, with an area under curve of 0.76 in receiver operating characteristics curve analysis. CONCLUSION: AKR1C1 and TKTL1 showed potential as biomarkers for diagnosis of LSIL in Mexican women, with similar sensitivity and specificity to the biomarkers used in clinical trials for diagnosis of LSIL.

Aldo-Keto Reductase 1C1 (AKR1C1) as the First Mutated Gene in a Family with Nonsyndromic Primary Lipedema.

Lipedema is an often underdiagnosed chronic disorder that affects subcutaneous adipose tissue almost exclusively in women, which leads to disproportionate fat accumulation in the lower and upper body extremities. Common comorbidities include anxiety, depression, and pain. The correlation between mood disorder and subcutaneous fat deposition suggests the involvement of steroids metabolism and neurohormones signaling, however no clear association has been established so far. In this study, we report on a family with three patients affected by sex-limited autosomal dominant nonsyndromic lipedema. They had been screened by whole exome sequencing (WES) which led to the discovery of a missense variant p.(Leu213Gln) in AKR1C1, the gene encoding for an aldo-keto reductase catalyzing the reduction of progesterone to its inactive form, 20-α-hydroxyprogesterone. Comparative molecular dynamics simulations of the wild-type vs. variant enzyme, corroborated by a thorough structural and functional bioinformatic analysis, suggest a partial loss-of-function of the variant. This would result in a slower and less efficient reduction of progesterone to hydroxyprogesterone and an increased subcutaneous fat deposition in variant carriers. Overall, our results suggest that AKR1C1 is the first candidate gene associated with nonsyndromic lipedema.

Combined analysis of RNA-sequence and microarray data reveals effective metabolism-based prognostic signature for neuroblastoma.

The relationship between metabolism reprogramming and neuroblastoma (NB) is largely unknown. In this study, one RNA-sequence data set (n = 153) was used as discovery cohort and two microarray data sets (n = 498 and n = 223) were used as validation cohorts. Differentially expressed metabolic genes were identified by comparing stage 4s and stage 4 NBs. Twelve metabolic genes were selected by LASSO regression analysis and integrated into the prognostic signature. The metabolic gene signature successfully stratifies NB patients into two risk groups and performs well in predicting survival of NB patients. The prognostic value of the metabolic gene signature is also independent with other clinical risk factors. Nine metabolism-related long non-coding RNAs (lncRNAs) were also identified and integrated into the metabolism-related lncRNA signature. The lncRNA signature also performs well in predicting survival of NB patients. These results suggest that the metabolic signatures have the potential to be used for risk stratification of NB. Gene set enrichment analysis (GSEA) reveals that multiple metabolic processes (including oxidative phosphorylation and tricarboxylic acid cycle, both of which are emerging targets for cancer therapy) are enriched in the high-risk NB group, and no metabolic process is enriched in the low-risk NB group. This result indicates that metabolism reprogramming is associated with the progression of NB and targeting certain metabolic pathways might be a promising therapy for NB.

The Interaction of lncRNA XLOC-2222497, AKR1C1, and Progesterone in Porcine Endometrium and Pregnancy.

The endometrium is an important tissue for pregnancy and plays an important role in reproduction. In this study, high-throughput transcriptome sequencing was performed in endometrium samples of Meishan and Yorkshire pigs on days 18 and 32 of pregnancy. Aldo-keto reductase family 1 member C1 (AKR1C1) was found to be a differentially expressed gene, and was identified by quantitative real-time PCR (qRT-PCR) and Western blot. Immunohistochemistry results revealed the cellular localization of the AKR1C1 protein in the endometrium. Luciferase activity assay demonstrated that the AKR1C1 core promoter region was located in the region from -706 to -564, containing two nuclear factor erythroid 2-related factor 2 (NRF2) binding sites (antioxidant response elements, AREs). XLOC-2222497 was identified as a nuclear long non-coding RNA (lncRNA) highly expressed in the endometrium. XLOC-2222497 overexpression and knockdown have an effect on the expression of AKR1C1. Endocrinologic measurement showed the difference in progesterone levels between Meishan and Yorkshire pigs. Progesterone treatment upregulated AKR1C1 and XLOC-2222497 expression in porcine endometrial epithelial cells. In conclusion, transcriptome analysis revealed differentially expressed transcripts during the early pregnancy process. Further experiments demonstrated the interaction of XLOC-2222497/AKR1C1/progesterone in the endometrium and provided new potential targets for pregnancy maintenance and its control.

Loss of AKR1C1 is a good prognostic factor in advanced NPC cases and increases chemosensitivity to cisplatin in NPC cells.

Cisplatin resistance is one of the main obstacles in the treatment of advanced nasopharyngeal carcinoma (NPC). AKR1C1 is a member of the Aldo-keto reductase superfamily (AKRs), which converts aldehydes and ketones to their corresponding alcohols and has been reported to be involved in chemotherapeutic resistance of multiple drugs. The expression and function of AKR1C1 in NPC have not been reported until now. The aim of this research was to investigate the expression of AKR1C1 and it is role in cisplatin resistance in NPC. AKR1C1 protein expression was detected by immunohistochemistry in human NPC tissues and by Western blot assays in NPC and immortalized nasopharyngeal epithelial cells. The effects of AKR1C1 knock-down by siRNA on proliferation, migration and invasion in NPC cells were evaluated by CCK8, wound healing and transwell assays. To evaluate the effects of AKR1C1 silencing on cisplatin sensitivity in NPC cells, CCK8 assays were used to detect cell proliferation, flow cytometry was used to detect cell cycle distribution, and flow cytometry and DAPI staining were used to detect cell apoptosis. AKR1C1 down-regulation was associated with advanced clinicopathological characters such as larger tumor size, more lymphatic nodes involvement, with metastasis and later clinical stages, while AKR1C1 down-regulation was a good prognostic factor for overall survival (OS) in NPC patients. In vitro study showed that AKR1C1 was not directly involved in the malignant biological behaviours such as proliferation, cell cycle progression and migration of NPC cells, whereas AKR1C1 knock-down could enhance cisplatin sensitivity of NPC cells. These results suggest that AKR1C1 is a potential marker for predicting cisplatin response and could serve as a molecular target to increase cisplatin sensitivity in NPC.

Enhancing Anti-Tumor Activity of Sorafenib Mesoporous Silica Nanomatrix in Metastatic Breast Tumor and Hepatocellular Carcinoma via the Co-Administration with Flufenamic Acid.

INTRODUCTION: Because tumor-associated inflammation is a hallmark of cancer treatment, in the present study, sorafenib mesoporous silica nanomatrix (MSNM@SFN) co-administrated with flufenamic acid (FFA, a non-steroidal anti-inflammatory drug (NSAID)) was investigated to enhance the anti-tumor activity of MSNM@SFN. METHODS: Metastatic breast tumor 4T1/luc cells and hepatocellular carcinoma HepG2 cells were selected as cell models. The effects of FFA in vitro on cell migration, PGE2 secretion, and AKR1C1 and AKR1C3 levels in 4T1/luc and HepG2 cells were investigated. The in vivo anti-tumor activity of MSNM@SFN co-administrating with FFA (MSNM@SFN+FFA) was evaluated in a 4T1/luc metastatic tumor model, HepG2 tumor-bearing nude mice model, and HepG2 orthotopic tumor-bearing nude mice model, respectively. RESULTS: The results indicated that FFA could markedly decrease cell migration, PGE2 secretion, and AKR1C1 and AKR1C3 levels in both 4T1/luc and HepG2 cells. The enhanced anti-tumor activity of MSNM@SFN+FFA compared with that of MSNM@SFN was confirmed in the 4T1/luc metastatic tumor model, HepG2 tumor-bearing nude mice model, and HepG2 orthotopic tumor-bearing nude mice model in vivo, respectively. DISCUSSION: MSNM@SFN co-administrating with FFA (MSNM@SFN+FFA) developed in this study is an alternative strategy for improving the therapeutic efficacy of MSNM@SFN via co-administration with NSAIDs.

The SIRT2-mediated deacetylation of AKR1C1 is required for suppressing its pro-metastasis function in Non-Small Cell Lung Cancer.

Aldo-keto reductase family 1 member C1 (AKR1C1) promotes malignancy of Non-Small Cell Lung Cancer (NSCLC) by activating Signal Transducer and Activator of Transcription 3 (STAT3) pathway. However, how the pro-metastatic functions of AKR1C1 are switched on/off remains unknown. Methods: Immunoprecipitation and LC-MS/MS analyses were performed to identify the acetylation on AKR1C1 protein, and the functional analyses (in vitro and in vivo) were performed to depict the contribution of acetylation to the pro-metastatic effects of AKR1C1. Results: Here we report that acetylated AKR1C1 on two lysine residues K185 & K201 is critical to its pro-metastatic role. The acetylation modification has no impact on the canonical enzymatic activity of AKR1C1, while it is required for the interaction between AKR1C1 to STAT3, which triggers the downstream transduction events, ultimately mobilizing cells. Importantly, the deacetylase Sirtuin 2 (SIRT2) is capable of deacetylating AKR1C1, inhibiting the transactivation of STAT3 target genes, thus suppressing the migration of cells. Conclusion: Acetylation on Lysines 185 and 201 of AKR1C1 dictates its pro-metastatic potential both in vitro and in vivo, and the reverting of acetylation by Sirtuin 2 provides potential therapeutic targets for treatment against metastatic NSCLC patients with high AKR1C1 expression.

Human dehydrogenase/reductase SDR family member 11 (DHRS11) and aldo-keto reductase 1C isoforms in comparison: Substrate and reaction specificity in the reduction of 11-keto-C19-steroids.

Recent studies have shown that an adrenal steroid 11ß-hydroxy-4-androstene-3,17-dione serves as the precursor to androgens, 11-ketotestosterone and 11-ketodihydrotestosterone (11KDHT). The biosynthetic pathways include the reduction of 3- and 17-keto groups of the androgen precursors 11-keto-C19-steroids, which has been reported to be mediated by three human enzymes; aldo-keto reductase (AKR)1C2, AKR1C3 and 17ß-hydroxysteroid dehydrogenase (HSD) type-3. To explore the contribution of the enzymes in the reductive metabolism, we kinetically compared the substrate specificity for 11-keto-C19-steroids among purified recombinant preparations of four AKRs (1C1, 1C2,1C3 and 1C4) and DHRS11, which shows 17ß-HSD activity. Although AKR1C1 did not reduce the 11-keto-C19-steroids, AKR1C3 and DHRS11 reduced 17-keto groups of 11-keto-4-androstene-3,17-dione, 11-keto-5α-androstane-3,17-dione (11K-Adione) and 11-ketoandrosterone with Km values of 5-28 µM. The 3-keto groups of 11KDHT and 11K-Adione were reduced by AKR1C4 (Km 1 µM) more efficiently than by AKR1C2 (Km 5 and 8 µM, respectively). GC/MS analysis of the products showed that DHRS11 acts as 17ß-HSD, and that AKR1C2 and AKR1C4 are predominantly 3α-HSDs, but formed a minor 3ß-metabolite from 11KDHT. Since DHRS11 was thus newly identified as 11-keto-C19-steroid reductase, we also investigated its substrate-binding mode by molecular docking and site-directed mutagenesis of Thr163 and Val200, and found the following structural features: 1). There is a space that accommodates the 11-keto group of the 11-keto-C19-steroids in the substrate-binding site. 2) Val200 is a critical determinant for exhibiting the strict 17ß-HSD activity of the enzyme, because the Val200Leu mutation resulted in both significant impairment of the 17ß-HSD activity and emergence of 3ß-HSD activity towards 5α-androstanes including 11KDHT.

AKR1C1 Activates STAT3 to Promote the Metastasis of Non-Small Cell Lung Cancer.

Metastasis is the leading cause of mortality for human non-small cell lung cancer (NSCLC). However, it is difficult to target tumor metastasis because the molecular mechanisms underlying NSCLC invasion and migration remain unclear. Methods: GEO data analyses and IHC analyses were performed to identify that the expression level of AKR1C1, a member of human aldo-keto reductase family, was highly elevated in patients with metastasis or metastatic foci of NSCLC patients. Functional analyses (in vitro and in vivo) and quantitative genomic analyses were preformed to confirm the pro-metastatic effects of AKR1C1 and the underlying mechanisms. The correlation of AKR1C1 with the prognosis of NSCLC patients was evaluated using Kaplan-Meier analyses. Results: in NSCLC patients, AKR1C1 expression was closely correlated with the metastatic potential of tumors. AKR1C1 overexpression in nonmetastatic cancer cells significantly promoted metastasis both in vitro and in vivo, whereas depletion of AKR1C1 in highly metastatic tumors potently alleviated these effects. Quantitative genomic and functional analyses revealed that AKR1C1 directly interacted with STAT3 and facilitated its phosphorylation-thus reinforcing the binding of STAT3 to the promoter regions of target genes-and then transactivated these genes, which ultimately promoted tumor metastasis. Further studies showed that AKR1C1 might facilitate the interaction of STAT3 with its upstream kinase JAK2. Intriguingly, AKR1C1 exerted these pro-metastatic effects in a catalytic-independent manner. In addition, a significant correlation between AKR1C1 and STAT3 pathway was observed in the metastatic foci of NSCLC patients, and the AKR1C1-STAT3 levels were highly correlated with a poor prognosis in NSCLC patients. Conclusions: taken together, we show that AKR1C1 is a potent inducer of NSCLC metastasis. Our study uncovers the active function of AKR1C1 as a key component of the STAT3 pathway, which promotes lung cancer metastasis, and highlights a candidate therapeutic target to potentially improve the survival of NSCLC patients with metastatic disease.

Molecular Docking, Synthesis and Biological Evaluation of Sulphonylureas/ Guanidine Derivatives as Promising Antidiabetic Agent.

BACKGROUND: A series of novel sulphonylureas/guanidine derivatives was designed, synthesized, and evaluated for the treatment of diabetes mellitus. In this study, the designed compounds were docked with AKR1C1 complexes by using glide docking program and docking calculations were performed to predict the binding affinity of the designed compounds with the binding pocket of protein 4YVP and QikProp program was used to predict the ADME/T properties of the analogues. METHODS: All the targeted derivatives were synthesized and purified by recrystallization. Synthesized compounds were characterized by various physicochemical and various spectroscopic techniques like melting point, thin layer chromatography, infrared spectroscopy (KBr pellets), mass spectroscopy(m/z), 1H NMR (DMSO-d6), and 13C NMR. The synthesized compounds were further studied for biological evolution by alloxan (150 mg/dl, intraperitonial) induced diabetic rat model for in-vivo studies. RESULT: Among all the synthesized derivatives, 5c and 5d were most potent as per binding energy. Compound 5i have shown a better plasma glucose reduction compared to glibenclamide. Hence, it will be further used as a lead compound to develop a more such kind of agent. CONCLUSION: The docking study revealed that in all designed sulphonylureas/ guanidine series of compounds 5c and 5d were found to be most potent compounds as per the binding energy compared to glibenclamide. With the help of detailed study of in vivo biological activity, we observed that compound 5i gives better result compared to glibenclamide as standard.