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Objective To determine the illness severity and mortality among COVID-19-infected healthcare workers (HCWs).Design A retrospective cohort study using population-level data. Secondary analysis was conducted on collated data from the Public Health Emergency Operations Centre (PHEOC) at the State Ministry of Health, Rivers State, Nigeria. Data were gathered from the COVID-19 patient database of the PHEOC on demographics, place of work, illness severity and outcome.Participants The cohort included all documented HCWs with confirmed COVID-19 infection (diagnosed by PCR).Primary and secondary outcome measures Illness severity defined as ‘hospitalisation required’ and treatment outcome labelled as ‘alive’ or ‘dead’ were the outcomes of interest.Results The mean age was 43 years and 50.5% of the cohort were female. Of the 301 HCWs infected, 187 patients were symptomatic with 32 requiring hospitalisation. Seven infected HCWs died of their COVID-19 infection, resulting in a case fatality ratio (CFR) of 2.3%. Population proportions for age groups, case presentation and mortality, would be significantly greater than those seen in the study population. Health professionals made up 79.7% (240) of the study cohort, with 68.8% (165) of them working at the teaching hospitals; the association between HCWs and health facilities they worked in, was significant. Symptomatic cases were more inclined to progress to severe illness (χ(1)2=15.219,α=

It is reported that in New Zealand financially disadvantaged adolescents are less likely to access orthodontic treatment than the more affluent in society.

Background: The Dental Aesthetic Index (DAI) has been used in many cross-sectional studies of population samples, but its use in assessing changes in malocclusion is less common. The aim of the present study was to describe the natural history of malocclusion and investigate the utility of the DAI as a measure for describing changes in malocclusion in a population-based sample of adolescents.

Abstract Background The Child Perception Questionnaire (CPQ11-14) is a self-report instrument developed to measure oral-health-related quality of life (OHRQoL) in 11-14-year-olds. Earlier reports confirm that the 16-item short-form version performs adequately, but there is a need to determine the measure's validity and properties in larger and more diverse samples and settings. Aim The objective of this study was to examine the performance of the 16-item short-form impact version of the CPQ11-14 in different communities and cultures with diverse caries experience. Method Cross-sectional epidemiological surveys of child oral health were conducted in two regions of New Zealand, one region in Brunei, and one in Brazil. Children were examined for dental caries (following WHO guidelines), and OHRQoL was measured using the 16-item short-form item-impact version of the CPQ11-14, along with two global questions on OHRQoL. Children in the 20% with the greatest caries experience (DMF score) were categorised as the highest caries quintile. Construct validity was evaluated by comparing the mean scale scores across the categories of caries experience; correlational construct validity was assessed by comparing mean scores and children's global ratings of oral health and well-being. Results There were substantial variations in caries experience among the different communities (from 1.8 in Otago to 4.9 in Northland) and in mean CPQ11-14 scores (from 11.5 in Northland to 16.8 in Brunei). In all samples, those in the most severe caries experience quintile had higher mean CPQ11-14 scores than those who were caries-free (P < 0.05). There were also greater CPQ scores in those with worse self-rated oral health, with the Otago sample presenting the most marked gradient across the response categories for self-rated oral health, from 'Excellent' to 'Fair/Poor' (9.6 to 19.7 respectively). Conclusion The findings suggest that the 16-item short-form item impact version of the CPQ11-14 performs well across diverse cultures and levels of caries experience. Reasons for the differences in mean CPQ scores among the communities are unclear and may reflect subtle socio-cultural differences in subjective oral health among these populations, but elucidating these requires further exploration of the face and content validity of the measure in different populations.

Abstract Background The role of microRNAs (miRNAs) in regulating gene expression is currently an area of intense interest. Relatively little is known, however, about the role of miRNAs in inflammatory and immunologically-driven disorders. In a mouse model, we have previously shown that miRNAs are potentially important therapeutic targets in allergic asthma, because inhibition of miR-126, one of a small subset of miRNAs upregulated in the airway wall, effectively suppressed Th2-driven airway inflammation and other features of asthma. In the present study, we extended investigation of the therapeutic potential of miRNA inhibition to our well-established model of chronic asthma. Methods Female BALB/c mice were systemically sensitised with ovalbumin (OVA) and chronically challenged with low mass concentrations of aerosolised OVA for up to 6 weeks. Airway tissue was obtained by blunt dissection and RNA was isolated for miRNA profiling. On the basis of the results obtained, animals were subsequently treated with either an antagomir to miR-126 (ant-miR-126) or a scrambled control antagomir once weekly during the 6 weeks of chronic challenge, and the effects on airway inflammation and remodelling were assessed using established morphometric techniques. Results Compared to naïve mice, there was selective upregulation of a modest number of miRNAs, notably miR-126, in the airway wall tissue of chronically challenged animals. The relative increase was maximal after 2 weeks of inhalational challenge and subsequently declined to baseline levels. Compared to treatment with the scrambled control, ant-miR-126 significantly reduced recruitment of intraepithelial eosinophils, but had no effect on the chronic inflammatory response, or on changes of airway remodelling. Conclusions In this model of chronic asthma, there was an initial increase in expression of a small number of miRNAs in the airway wall, notably miR-126. However, this later declined to baseline levels, suggesting that sustained changes in miRNA may not be essential for perpetuation of chronic asthma. Moreover, inhibition of miR-126 by administration of an antagomir suppressed eosinophil recruitment into the airways but had no effect on chronic inflammation in the airway wall, or on changes of remodelling, suggesting that multiple miRNAs are likely to regulate the development of these lesions.

Abstract Background Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care. EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. Methods/Design EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible. The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events. A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. Trial Registration: ISRCTN44464607.

Abstract Background Early-life respiratory viral infections, notably with respiratory syncytial virus (RSV), increase the risk of subsequent development of childhood asthma. The purpose of this study was to assess whether early-life infection with a species-specific model of RSV and subsequent allergen exposure predisposed to the development of features of asthma. Methods We employed a unique combination of animal models in which BALB/c mice were neonatally infected with pneumonia virus of mice (PVM, which replicates severe RSV disease in human infants) and following recovery, were intranasally sensitised with ovalbumin. Animals received low-level challenge with aerosolised antigen for 4 weeks to elicit changes of chronic asthma, followed by a single moderate-level challenge to induce an exacerbation of inflammation. We then assessed airway inflammation, epithelial changes characteristic of remodelling, airway hyperresponsiveness (AHR) and host immunological responses. Results Allergic airway inflammation, including recruitment of eosinophils, was prominent only in animals that had recovered from neonatal infection with PVM and then been sensitised and chronically challenged with antigen. Furthermore, only these mice exhibited an augmented Th2-biased immune response, including elevated serum levels of anti-ovalbumin IgE and IgG1 as well as increased relative expression of Th2-associated cytokines IL-4, IL-5 and IL-13. By comparison, development of AHR and mucous cell change were associated with recovery from PVM infection, regardless of subsequent allergen challenge. Increased expression of IL-25, which could contribute to induction of a Th2 response, was demonstrable in the lung following PVM infection. Signalling via the IL-4 receptor α chain was crucial to the development of allergic inflammation, mucous cell change and AHR, because all of these were absent in receptor-deficient mice. In contrast, changes of remodelling were evident in mice that received chronic allergen challenge, regardless of neonatal PVM infection, and were not dependent on signalling via the IL-4 receptor. Conclusion In this mouse model, interaction between early-life viral infection and allergen sensitisation/challenge is essential for development of the characteristic features of childhood asthma, including allergic inflammation and a Th2-biased immune response.

Abstract Background It is speculated that high saturated fat very low carbohydrate diets (VLCARB) have adverse effects on cardiovascular risk but evidence for this in controlled studies is lacking. The objective of this study was to compare, under isocaloric conditions, the effects of a VLCARB to 2 low saturated fat high carbohydrate diets on body composition and cardiovascular risk. Methods Eighty three subjects, 48 ± 8 y, total cholesterol 5.9 ± 1.0 mmol/L, BMI 33 ± 3 kg/m2 were randomly allocated to one of 3 isocaloric weight loss diets (6 MJ) for 8 weeks and on the same diets in energy balance for 4 weeks: Very Low Fat (VLF) (CHO:Fat:Protein; %SF = 70:10:20; 3%), High Unsaturated Fat (HUF) = (50:30:20; 6%), VLCARB (4:61:35; 20%) Results Percent fat mass loss was not different between diets VLCARB -4.5 ± 0.5, VLF-4.0 ± 0.5, HUF -4.4 ± 0.6 kg). Lean mass loss was 32-31% on VLCARB and VLF compared to HUF (21%) (P < 0.05). LDL-C increased significantly only on VLCARB by 7% (p < 0.001 compared with the other diets) but apoB was unchanged on this diet and HDL-C increased relative to the other 2 diets. Triacylglycerol was lowered by 0.73 ± 0.12 mmol/L on VLCARB compared to -0.15 ± 0.07 mmol/L on HUF and -0.06 ± 0.13 mmol/L on VLF (P < 0.001). Plasma homocysteine increased 6.6% only on VLCARB (P = 0.026). VLCARB lowered fasting insulin 33% compared to a 19% fall on HUF and no change on VLF (P < 0.001). The VLCARB meal also provoked significantly lower post prandial glucose and insulin responses than the VLF and HUF meals. All diets decreased fasting glucose, blood pressure and CRP (P < 0.05). Conclusion Isocaloric VLCARB results in similar fat loss than diets low in saturated fat, but are more effective in improving triacylglycerols, HDL-C, fasting and post prandial glucose and insulin concentrations. VLCARB may be useful in the short-term management of subjects with insulin resistance and hypertriacylglycerolemia.

The ovaries are key steroid hormone production sites in post-pubertal females. However, current research on steroidogenic enzymes, endogenous hormone concentrations and their effects on healthy ovarian function and malignant development is limited. Here, we discuss the importance of steroid enzymes in normal and malignant ovaries, alongside hormone concentrations, receptor expression and action. Key enzymes include STS, 3β-HSD2, HSD17B1, ARK1C3, and aromatase, which influence ovarian steroidal action. Both androgen and oestrogen action, via their facilitating enzyme, drives ovarian follicle activation, development and maturation in healthy ovarian tissue. In ovarian cancer, some data suggest STS and oestrogen receptor α may be linked to aggressive forms, while various oestrogen-responsive factors may be involved in ovarian cancer metastasis. In contrast, androgen receptor expression and action vary across ovarian cancer subtypes. For future studies investigating steroidogenesis and steroidal activity in ovarian cancer, it is necessary to differentiate between disease subtypes for a comprehensive understanding., (© 2024 The Author(s).)

All three possible sulfamate derivatives of the selective estrogen receptor modulator Raloxifene (bis-sulfamate 7 and two mono-sulfamates 8-9) were synthesized and evaluated as inhibitors of the clinical drug target steroid sulfatase (STS), both in cell-free and in cell-based assays, and also as estrogen receptor (ER) modulators. Bis-sulfamate 7 was the most potent STS inhibitor with an IC 50 of 12.2 nM in a whole JEG3 cell-based assay, with the two mono-sulfamates significantly weaker. The estrogen receptor-modulating activities of 7-9 showed generally lower affinities compared to Raloxifene HCl, diethylstilbestrol and other known ligands, with mono-sulfamate 8 being the best ligand (Ki of 1.5 nM) for ERα binding, although 7 had a Ki of 13 nM and both showed desirable antagonist activity. The antiproliferative activities of the sulfamate derivatives against the T-47D breast cancer cell line showed 7 as most potent (GI 50  = 7.12 µM), comparable to that of Raloxifene. Compound 7 also showed good antiproliferative potency in the NCI-60 cell line panel with a GI 50 of 1.34 µM against MDA-MB-231 breast cancer cells. Stability testing of 7-9 showed that bis-sulfamate 7 hydrolyzed by desulfamoylation at a surprisingly rapid rate, initially leading selectively to 8 and finally to Raloxifene 3 without formation of 9. The mechanisms of these hydrolysis reactions could be extensively rationalized. Conversion of Raloxifene (3) into its bis-sulfamate (7) thus produced a promising drug lead with nanomolar dual activity as an STS inhibitor and ERα antagonist, as a potential candidate for treatment of estrogen-dependent breast cancer., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Adrenocortical carcinoma (ACC) is an aggressive malignancy with limited treatment options. Polo-like kinase 1 (PLK1) is a promising drug target; PLK1 inhibitors (PLK1i) have been investigated in solid cancers and are more effective in TP53-mutated cases. We evaluated PLK1 expression in ACC samples and the efficacy of two PLK1i in ACC cell lines with different genetic backgrounds. PLK1 protein expression was investigated by immunohistochemistry in tissue samples and correlated with clinical data. The efficacy of rigosertib (RGS), targeting RAS/PI3K, CDKs and PLKs, and poloxin (Pol), specifically targeting the PLK1 polo-box domain, was tested in TP53-mutated NCI-H295R, MUC-1, and CU-ACC2 cells and in TP53 wild-type CU-ACC1. Effects on proliferation, apoptosis, and viability were determined. PLK1 immunostaining was stronger in TP53-mutated ACC samples vs wild-type (P = 0.0017). High PLK1 expression together with TP53 mutations correlated with shorter progression-free survival (P= 0.041). NCI-H295R showed a time- and dose-dependent reduction in proliferation with both PLK1i (P< 0.05at 100 nM RGS and 30 µM Pol). In MUC-1, a less pronounced decrease was observed (P< 0.05at 1000 nM RGS and 100 µM Pol). 100 nM RGS increased apoptosis in NCI-H295R (P< 0.001), with no effect on MUC-1. CU-ACC2 apoptosis was induced only at high concentrations (P < 0.05 at 3000 nM RGS and 100 µM Pol), while proliferation decreased at 1000 nM RGS and 30 µM Pol. CU-ACC1 proliferation reduced, and apoptosis increased, only at 100 µM Pol. TP53-mutated ACC cell lines demonstrated better response to PLK1i than wild-type CU-ACC1. These data suggest PLK1i may be a promising targeted treatment of a subset of ACC patients, pre-selected according to tumour genetic signature.

The colon is the largest hormonally active tissue in the human body. It has been known for over a hundred years that various hormones and bioactive peptides play important roles in colon function. More recently there is a growing interest in the role the sex steroids, oestrogens and androgens, may play in both normal colon physiology and colon pathophysiology. In this review, we examine the potential role oestrogens and androgens play in the colon. The metabolism and subsequent action of sex steroids in colonic tissue is discussed and how these hormones impact colon motility is investigated. Furthermore, we also determine how oestrogens and androgens influence colorectal cancer incidence and development and highlight potential new therapeutic targets for this malignancy. This review also examines how sex steroids potentially impact the severity and progression of other colon disease, such as diverticulitis, irritable bowel syndrome, and polyp formation., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

A central part of human sulfation pathways is the spatially and temporally controlled desulfation of biologically highly potent steroid hormones. The responsible enzyme - steroid sulfatase (STS) - is highly expressed in placenta and peripheral tissues, such as fat, colon, and the brain. The shape of this enzyme and its mechanism are probably unique in biochemistry. STS was believed to be a transmembrane protein, spanning the Golgi double-membrane by stem region formed by two extended internal alpha-helices. New crystallographic data however challenge this view. STS now is portraited as a trimeric membrane-associated complex. We discuss the impact of these results on STS function and sulfation pathways in general and we hypothesis that this new STS structural understanding suggests product inhibition to be a regulator of STS enzymatic activity., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Aromatase (CYP19A1) inhibitors are the mainstay therapeutics for the treatment of hormone dependant breast cancer, which accounts for approximately 70% of all breast cancer cases. However, increased resistance to the clinically used aromatase inhibitors, including letrozole and anastrazole, and off target effects, necessitates the development of aromatase inhibitors with improved drug profiles. The development of extended 4th generation pyridine based aromatase inhibitors with dual binding (haem and access channel) is therefore of interest and here we describe the design, synthesis and computational studies. Cytotoxicity and selectivity studies identified the pyridine derivative (4-bromophenyl)(6-(but-2-yn-1-yloxy)benzofuran-2-yl)(pyridin-3-yl)methanol (10c) as optimal with CYP19A1 IC 50 0.83 nM ( c.f. letrozole IC 50 0.70 nM), and an excellent cytotoxicity and selectivity profile. Interestingly, computational studies for the 6- O -butynyloxy (10) and 6- O -pentynyloxy (11) derivatives identified an alternative access channel lined by Phe221, Trp224, Gln225 and Leu477, providing further insight into the potential binding mode and interactions of the non-steroidal aromatase inhibitors., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

2-Difluoromethoxyestratriene derivatives were designed to improve potency and in vivo stability of the drug candidate 2-methoxyestradiol (2ME2). Compound evaluation in vitro against the proliferation of MCF-7 and MDA MB-231 breast cancer cells, as inhibitors of tubulin polymerisation and also steroid sulfatase (STS) both in cell lysates and in whole cells, showed promising activities. In antiproliferative assays 2-difluoromethoxyestradiol was less potent than 2ME2, but its sulfamates were often more potent than their corresponding non-fluorinated analogues. The fluorinated bis-sulfamate is a promising antiproliferative agent in MCF-7 cells (GI 50 0.28 μM) vs the known 2-methoxyestradiol-3,17-O,O-bissulfamate (STX140, GI 50 0.52 μM), confirming the utility of our approach. Compounds were also evaluated in the NCI 60-cell line panel and the fluorinated bis-sulfamate derivative displayed very good overall activities with a sub-micromolar average GI 50 . It was a very potent STS inhibitor in whole JEG-3 cells (IC 50 3.7 nM) similar to STX140 (4.2 nM) and additionally interferes with tubulin assembly in vitro and colchicine binding to tubulin. An X-ray study of 2-difluoromethoxy-3-benzyloxyestra-1,3,5(10)-trien-17-one examined conformational aspects of the fluorinated substituent. The known related derivative 2-difluoromethyl-3-sulfamoyloxyestrone was evaluated for STS inhibition in whole JEG-3 cells and showed an excellent IC 50 of 55 pM., (© 2022 Wiley-VCH GmbH.)

One in every eight women will be diagnosed with breast cancer during their lifetime and approximately 70% of all patients are oestrogen receptor (ER) positive depending upon oestrogen for their growth accounting for third generation aromatase (CYP19A1) inhibitors being the mainstay in the treatment of ER-positive breast cancer. Despite the success of current aromatase inhibitors, acquired resistance occurs after prolonged therapy. Although the precise mechanisms of resistance are not known, lack of cross resistance among aromatase inhibitors drives the need for a newer generation of inhibitors to overcome this resistance alongside minimising toxicity and adverse effects. Novel triazole-based inhibitors were designed based on previously published parent compound 5a, making use of the now available crystal structure of CYP19A1 (PDB 3S79), to make modifications at specific sites to explore the potential of dual binding at both the active site and the access channel. Modifications included adding long chain substituents e.g. but-2-ynyloxy and pent-2-ynyloxy at different positions including the most active compound 13h with IC 50 value in the low picomolar range (0.09 nM). Aromatase inhibition results paired with molecular dynamics studies provided a clear structure activity relationship and favourable dual binding mode was verified. Toxicity assays and CYP selectivity profile studies for some example compounds were performed to assess the safety profile of the prepared inhibitors providing the basis for the 4th generation nonsteroidal aromatase inhibitors., (Copyright © 2022 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

Context: The adrenal cortex produces specific steroid hormones including steroid sulfates such as dehydroepiandrosterone sulfate (DHEAS), the most abundant steroid hormone in the human circulation. Steroid sulfation involves a multistep enzyme machinery that may be impaired by inborn errors of steroid metabolism. Emerging data suggest a role of steroid sulfates in the pathophysiology of adrenal tumors and as potential biomarkers., Evidence Acquisition: Selective literature search using "steroid," "sulfat*," "adrenal," "transport," "mass spectrometry" and related terms in different combinations., Evidence Synthesis: A recent study highlighted the tissue abundance of estrogen sulfates to be of prognostic impact in adrenocortical carcinoma tissue samples using matrix-assisted laser desorption ionization mass spectrometry imaging. General mechanisms of sulfate uptake, activation, and transfer to substrate steroids are reasonably well understood. Key aspects of this pathway, however, have not been investigated in detail in the adrenal; these include the regulation of substrate specificity and the secretion of sulfated steroids. Both for the adrenal and targeted peripheral tissues, steroid sulfates may have relevant biological actions beyond their cognate nuclear receptors after desulfation. Impaired steroid sulfation such as low DHEAS in Cushing adenomas is of diagnostic utility, but more comprehensive studies are lacking. In bioanalytics, the requirement of deconjugation for gas-chromatography/mass-spectrometry has precluded the study of steroid sulfates for a long time. This limitation may be overcome by liquid chromatography/tandem mass spectrometry., Conclusions: A role of steroid sulfation in the pathophysiology of adrenal tumors has been suggested and a diagnostic utility of steroid sulfates as biomarkers is likely. Recent analytical developments may target sulfated steroids specifically., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

Steroid sulphatase (STS), involved in the hydrolysis of steroid sulphates, plays an important role in the formation of both active oestrogens and androgens. Since these steroids significantly impact the proliferation of both oestrogen- and androgen-dependent cancers, many research groups over the past 30 years have designed and developed STS inhibitors. One of the main contributors to this field has been Prof. Barry Potter, previously at the University of Bath and now at the University of Oxford. Upon Prof. Potter's imminent retirement, this review takes a look back at the work on STS inhibitors and their contribution to our understanding of sulphate biology and as potential therapeutic agents in hormone-dependent disease. A number of potent STS inhibitors have now been developed, one of which, Irosustat (STX64, 667Coumate, BN83495), remains the only one to have completed phase I/II clinical trials against numerous indications (breast, prostate, endometrial). These studies have provided new insights into the origins of androgens and oestrogens in women and men. In addition to the therapeutic role of STS inhibition in breast and prostate cancer, there is now good evidence to suggest they may also provide benefits in patients with colorectal and ovarian cancer, and in treating endometriosis. To explore the potential of STS inhibitors further, a number of second- and third-generation inhibitors have been developed, together with single molecules that possess aromatase-STS inhibitory properties. The further development of potent STS inhibitors will allow their potential therapeutic value to be explored in a variety of hormone-dependent cancers and possibly other non-oncological conditions.

The protein disulphide isomerase (PDI) gene family is a large, diverse group of enzymes recognised for their roles in disulphide bond formation within the endoplasmic reticulum (ER). PDI therefore plays an important role in ER proteostasis, however, it also shows involvement in ER stress, a characteristic recognised in multiple disease states, including cancer. While the exact mechanisms by which PDI contributes to tumorigenesis are still not fully understood, PDI exhibits clear involvement in the unfolded protein response (UPR) pathway. The UPR acts to alleviate ER stress through the activation of ER chaperones, such as PDI, which act to refold misfolded proteins, promoting cell survival. PDI also acts as an upstream regulator of the UPR pathway, through redox regulation of UPR stress receptors. This demonstrates the pro-protective roles of PDI and highlights PDI as a potential therapeutic target for cancer treatment. Recent research has explored the use of PDI inhibitors with PACMA 31 in particular, demonstrating promising anti-cancer effects in ovarian cancer. This review discusses the properties and functions of PDI family members and focuses on their potential as a therapeutic target for cancer treatment., (© 2021 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Androgens are the obligatory precursors of estrogens. In humans, classic androgen biosynthesis yields testosterone, thought to represent the predominant circulating active androgen both in men and women. However, recent work has shown that 11-ketotestosterone, derived from the newly described 11-oxygenated androgen biosynthesis pathway, makes a substantial contribution to the active androgen pool in women. Considering that classic androgens are the obligatory substrates for estrogen biosynthesis catalyzed by cytochrome P450 aromatase, we hypothesized that 11-oxygenated androgens are aromatizable. Here we use steroid analysis by tandem mass spectrometry to demonstrate that human aromatase generates 11-oxygenated estrogens from 11-oxygenated androgens in 3 different cell-based aromatase expression systems and in human ex vivo placenta explant cultures. We also show that 11-oxygenated estrogens are generated as a byproduct of the aromatization of classic androgens. We show that 11β-hydroxy-17β-estradiol binds and activates estrogen receptors α and β and that 11β-hydroxy-17β-estradiol and the classic androgen pathway-derived active estrogen, 17β-estradiol, are equipotent in stimulating breast cancer cell line proliferation and expression of estrogen-responsive genes. 11-oxygenated estrogens were, however, not detectable in serum from individuals with high aromatase levels (pregnant women) and elevated 11-oxygenated androgen levels (patients with congenital adrenal hyperplasia or adrenocortical carcinoma). Our data show that while 11-oxygenated androgens are aromatizable in vitro and ex vivo, the resulting 11-oxygenated estrogens are not detectable in circulation, suggesting that 11-oxygenated androgens function primarily as androgens in vivo., (© The Author(s) 2020. Published by Oxford University Press on behalf of the Endocrine Society.)

Aim and Background: A systemic method for the application of Ilizarov fixators and on-table fracture reduction is described in this instructional article. This technique has been developed from the unit's practice in adult patients. The indications, underlying principles and rationale for the method are also discussed., Technique: The basic concept involves the construction of a series of concentric, colinear rings aligned with the mechanical axis of the limb. An orthogonal ring block is initially placed on the proximal segment and extended distally. Wire to ring reduction techniques are used resulting in the contact, alignment and stability required for early full weight-bearing, free movement of knee and ankle, and subsequent healing., Conclusion and Clinical Significance: Our step-by-step guide takes the reader through a systematic approach to surgery along with tips and tricks on how to achieve reduction and avoid the common pitfalls. With this method, it is possible to achieve an on-table reduction and correction of a multiplanar deformity without the use of expensive hexapod technology. This may allow less experienced users reproduce the technique with a shorter learning curve., How to Cite This Article: Messner J, Prior CP, Pincher B et al . Ilizarov Method for Acute Paediatric Tibial Fractures. Strategies Trauma Limb Reconstr 2021;16(1):46-52., Competing Interests: Source of support: Nil Conflict of interest: None, (Copyright © 2021; Jaypee Brothers Medical Publishers (P) Ltd.)

Steroid sulfatase (STS) has recently emerged as a drug target for management of hormone-dependent malignancies. In the present study, a new series of twenty-one aryl amido-linked sulfamate derivatives 1a-u was designed and synthesized, based upon a cyclohexyl lead compound. All members were evaluated as STS inhibitors in a cell-free assay. Adamantyl derivatives 1h and 1p-r were the most active with more than 90% inhibition at 10 µM concentration and, for those with the greatest inhibitory activity, IC 50 values were determined. These compounds exhibited STS inhibition within the range of ca 25-110 nM. Amongst them, compound 1q possessing a o-chlorobenzene sulfamate moiety exhibited the most potent STS inhibitory activity with an IC 50 of 26 nM. Furthermore, to assure capability to pass through the cell lipid bilayer, compounds with low IC 50 values were tested against STS activity in JEG-3 whole-cell assays. Consequently, 1h and 1q demonstrated IC 50 values of ca 14 and 150 nM, respectively. Thus, compound 1h is 31 times more potent than the corresponding cyclohexyl lead (IC 50 value = 421 nM in a JEG-3 whole-cell assay). Furthermore, the most potent STS inhibitors (1h and 1p-r) were evaluated for their antiproliferative activity against the estrogen-dependent breast cancer cell line T-47D. They showed promising activity with single digit micromolar IC 50 values (ca 1-6 µM) and their potency against T-47D cells was comparable to that against STS enzyme. In conclusion, this new class of adamantyl-containing aryl sulfamate inhibitor has potential for further development against hormone-dependent tumours., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Steroid sulfatase (STS) transforms hormone precursors into active steroids. Thus, it represents a target of intense research regarding hormone-dependent cancers. In this study, three ligand-based pharmacophore models were developed to identify STS inhibitors from natural sources. In a pharmacophore-based virtual screening of a curated molecular TCM database, lanostane-type triterpenes (LTTs) were predicted as STS ligands. Three traditionally used polypores rich in LTTs, i.e., Ganoderma lucidum Karst., Gloeophyllum odoratum Imazeki, and Fomitopsis pinicola Karst., were selected as starting materials. Based on eighteen thereof isolated LTTs a structure activity relationship for this compound class was established with piptolinic acid D (1), pinicolic acid B (2), and ganoderol A (3) being the most pronounced and first natural product STS inhibitors with IC 50 values between 10 and 16 µM. Molecular docking studies proposed crucial ligand target interactions and a prediction tool for these natural compounds correlating with experimental findings., Competing Interests: Declaration of Competing Interest None., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Two new piperazinyl-ureido single ring aryl sulfamate-based inhibitor series were designed against the emerging oncology drug target steroid sulfatase (STS), for which there are existing potent steroidal and non-steroidal agents in clinical trials. 4-(Piperazinocarbonyl)aminosulfamates (5-31) were obtained by reacting 4-hydroxyarylamines with phenylchloroformate, subsequent sulfamoylation of the resulting hydroxyarylcarbamates and coupling of the product with 1-substituted piperazines. Pyrimidinyl-piperazinourea sulfamates (35-42) were synthesized by pyrimidine ring closure of 4-Boc-piperazine-1-carboxamidine with 3-(dimethylamino)propenones, deprotection and coupling with the sulfamoylated building block. Target ureidosulfamates 5-31 and 35-42 were evaluated both as STS inhibitors in vitro using a lysate of JEG-3 human placenta choriocarcinoma cell line and in a whole cell assay. SAR conclusions were drawn from both series. In series 35-42 the best inhibitory activity is related to the presence of a benzofuryl on the pyrimidine ring. In series 5-31 the best inhibitory activity was shown by the ureas bearing 4-chlorophenyl, 3,4-dichlorophenyl groups or aliphatic chains at the piperazino 4-nitrogen displaying IC 50 in the 33-94 nM concentration range. Final optimization to the low nanomolar level was achieved through substitution of the arylsulfamate ring with halogens. Four halogenated arylsulfamates of high potency were achieved and two of these 19 and 20 had IC 50 values of 5.1 and 8.8 nM respectively and are attractive for potential in vivo evaluation and further development. We demonstrate the optimization of this new series to low nanomolar potency, employing fluorine substitution, providing potent membrane permeant inhibitors with further development potential indicating piperazinyl-ureido aryl sulfamate derivatives as an attractive new class of STS inhibitors., (Copyright © 2019 Elsevier Masson SAS. All rights reserved.)

Chemometric methods and correlation of spectroscopic or spectrometric data with bioactivity results are known to improve dereplication in classical bio-guided isolation approaches. However, in drug discovery from natural sources the isolation of bioactive constituents from a crude extract containing close structural analogues remains a significant challenge. This study is a 1 H NMR-MS workflow named ELINA (Eliciting Nature's Activities) which is based on statistical heterocovariance analysis (HetCA) of 1 H NMR spectra detecting chemical features that are positively ("hot") or negatively ("cold") correlated with bioactivity prior to any isolation. ELINA is exemplified in the discovery of steroid sulfatase (STS) inhibiting lanostane triterpenes (LTTs) from a complex extract of the polypore fungus Fomitopsis pinicola.

Sulfation and desulfation pathways represent highly dynamic ways of shuttling, repressing and re-activating steroid hormones, thus controlling their immense biological potency at the very heart of endocrinology. This theme currently experiences growing research interest from various sides, including, but not limited to, novel insights about phospho-adenosine-5'-phosphosulfate synthase and sulfotransferase function and regulation, novel analytics for steroid conjugate detection and quantification. Within this review, we will also define how sulfation pathways are ripe for drug development strategies, which have translational potential to treat a number of conditions, including chronic inflammatory diseases and steroid-dependent cancers., (© 2018 Society for Endocrinology.)

Adrenocortical carcinoma (ACC) is an aggressive malignancy with poor response to chemotherapy. In this study, we evaluated a potential new treatment target for ACC, focusing on the mitochondrial reduced form of NAD phosphate (NADPH) generator nicotinamide nucleotide transhydrogenase (NNT). NNT has a central role within mitochondrial antioxidant pathways, protecting cells from oxidative stress. Inactivating human NNT mutations result in congenital adrenal insufficiency. We hypothesized that NNT silencing in ACC cells will induce toxic levels of oxidative stress. To explore this, we transiently knocked down NNT in NCI-H295R ACC cells. As predicted, this manipulation increased intracellular levels of oxidative stress; this resulted in a pronounced suppression of cell proliferation and higher apoptotic rates, as well as sensitization of cells to chemically induced oxidative stress. Steroidogenesis was paradoxically stimulated by NNT loss, as demonstrated by mass spectrometry-based steroid profiling. Next, we generated a stable NNT knockdown model in the same cell line to investigate the longer lasting effects of NNT silencing. After long-term culture, cells adapted metabolically to chronic NNT knockdown, restoring their redox balance and resilience to oxidative stress, although their proliferation remained suppressed. This was associated with higher rates of oxygen consumption. The molecular pathways underpinning these responses were explored in detail by RNA sequencing and nontargeted metabolome analysis, revealing major alterations in nucleotide synthesis, protein folding, and polyamine metabolism. This study provides preclinical evidence of the therapeutic merit of antioxidant targeting in ACC as well as illuminating the long-term adaptive response of cells to oxidative stress.

In women, establishment of pregnancy is dependent upon 'fine-tuning' of the endometrial microenvironment, which is mediated by terminal differentiation (decidualisation) of endometrial stromal fibroblasts (ESFs). We have demonstrated that intracrine steroid metabolism plays a key role in regulating decidualisation and is essential for time-dependent expression of key factors required for endometrial receptivity. The primary aim of the current study was to determine whether sulphated steroids can act as precursors to bioactive sex steroids during decidualisation. We used primary human ESF and a robust in vitro model of decidualisation to assess the expression of genes associated with sulphation, desulphation and transport of sulphated steroids in human ESF as well as the impact of the steroid sulphatase (STS) inhibitor STX64 (Irosustat). We found evidence for an increase in both expression and activity of STS in response to a decidualisation stimulus with abrogation of oestrone biosynthesis and decreased secretion of the decidualisation marker IGFBP1 in the presence of STX64. These results provide novel insight into the contribution of STS to the intracrine regulation of decidualisation., (© 2018 The authors.)

Quinazolinone-based anticancer agents were designed, decorated with functional groups from a 2-methoxyestradiol-based microtubule disruptor series, incorporating the aryl sulfamate motif of steroid sulfatase (STS) inhibitors. The steroidal AB-ring system was mimicked, favoring conformations with an N-2 substituent occupying D-ring space. Evaluation against breast and prostate tumor cell lines identified 7b with DU-145 antiproliferative activity (GI 50 300 nM). A preliminary structure-activity relationship afforded compounds (e.g., 7j GI 50 50 nM) with activity exceeding that of the parent. Both 7b and 7j inhibit tubulin assembly in vitro and colchicine binding, and 7j was successfully co-crystallized with the αβ-tubulin heterodimer as the first of its class, its sulfamate group interacting positively at the colchicine binding site. Microtubule destabilization by 7j is likely achieved by preventing the curved-to-straight conformational transition in αβ-tubulin. Quinazolinone sulfamates surprisingly showed weak STS inhibition. Preliminary in vivo studies in a multiple myeloma xenograft model for 7b showed oral activity, confirming the promise of this template.

Nicotinamide nucleotide transhydrogenase, NNT, is a ubiquitous protein of the inner mitochondrial membrane with a key role in mitochondrial redox balance. NNT produces high concentrations of NADPH for detoxification of reactive oxygen species by glutathione and thioredoxin pathways. In humans, NNT dysfunction leads to an adrenal-specific disorder, glucocorticoid deficiency. Certain substrains of C57BL/6 mice contain a spontaneously occurring inactivating Nnt mutation and display glucocorticoid deficiency along with glucose intolerance and reduced insulin secretion. To understand the underlying mechanism(s) behind the glucocorticoid deficiency, we performed comprehensive RNA-seq on adrenals from wild-type (C57BL/6N), mutant (C57BL/6J) and BAC transgenic mice overexpressing Nnt (C57BL/6J BAC ). The following results were obtained. Our data suggest that Nnt deletion (or overexpression) reduces adrenal steroidogenic output by decreasing the expression of crucial, mitochondrial antioxidant ( Prdx3 and Txnrd2 ) and steroidogenic ( Cyp11a1 ) enzymes. Pathway analysis also revealed upregulation of heat shock protein machinery and haemoglobins possibly in response to the oxidative stress initiated by NNT ablation. In conclusion, using transcriptomic profiling in adrenals from three mouse models, we showed that disturbances in adrenal redox homeostasis are mediated not only by under expression of NNT but also by its overexpression. Further, we demonstrated that both under expression or overexpression of NNT reduced corticosterone output implying a central role for it in the control of steroidogenesis. This is likely due to a reduction in the expression of a key steroidogenic enzyme, Cyp11a1, which mirrored the reduction in corticosterone output., (© 2018 The authors.)

Context: Estrogens affect the incidence and progression of colorectal cancer (CRC), although the precise molecular mechanisms remain ill-defined., Objective: The present study investigated prereceptor estrogen metabolism through steroid sulphatase (STS) and 17β-hydroxysteroid dehydrogenase activity and subsequent nongenomic estrogen signaling in human CRC tissue, in The Cancer Genome Atlas colon adenocarcinoma data set, and in in vitro and in vivo CRC models. We aimed to define and therapeutically target pathways through which estrogens alter CRC proliferation and progression., Design, Setting, Patients, and Interventions: Human CRC samples with normal tissue-matched controls were collected from postmenopausal female and age-matched male patients. Estrogen metabolism enzymes and nongenomic downstream signaling pathways were determined. CRC cell lines were transfected with STS and cultured for in vitro and in vivo analysis. Estrogen metabolism was determined using an ultra-performance liquid chromatography-tandem mass spectrometry method., Primary Outcome Measure: The proliferative effects of estrogen metabolism were evaluated using 5-bromo-2'-deoxyuridine assays and CRC mouse xenograft studies., Results: Human CRC exhibits dysregulated estrogen metabolism, favoring estradiol synthesis. The activity of STS, the fundamental enzyme that activates conjugated estrogens, is significantly (P < 0.001) elevated in human CRC compared with matched controls. STS overexpression accelerates CRC proliferation in in vitro and in vivo models, with STS inhibition an effective treatment. We defined a G-protein-coupled estrogen receptor (GPER) proproliferative pathway potentially through increased expression of connective tissue growth factor in CRC., Conclusion: Human CRC favors estradiol synthesis to augment proliferation via GPER stimulation. Further research is required regarding whether estrogen replacement therapy should be used with caution in patients at high risk of developing CRC., (Copyright © 2017 Endocrine Society)

Hormone replacement therapy (HRT) affects the incidence and potential progression of colorectal cancer (CRC). As HRT primarily consists of estrone sulfate (E 1 S), understanding whether this conjugated estrogen is transported and metabolized in CRC will define its potential effect in this malignancy. Here, we show that a panel of CRC cell lines (Colo205, Caco2, HCT116, HT-29) have steroid sulfatase (STS) activity, and thus can hydrolyze E 1 S. STS activity is significantly higher in CRC cell lysate, suggesting the importance of E 1 S transport in intracellular STS substrate availability. As E 1 S transport is regulated by the expression pattern of certain solute carrier organic anion transporter polypeptides, we show that in CRC OATP4A1 is the most abundantly expressed transporter. All four CRC cell lines rapidly transported E 1 S into cells, with this effect significantly inhibited by the competitive OATP inhibitor BSP. Transient knockdown of OATP4A1 significantly disrupted E 1 S uptake. Examination of estrogen receptor status showed ERα was present in Colo205 and Caco2 cells. None of the cells expressed ERβ. Intriguingly, HCT116 and HT29 cells strongly expressed the G protein coupled estrogen receptor (GPER), and that stimulation of this receptor with estradiol (E 2 ) and G1, a GPER agonist, significantly ( p < 0.01) increased STS activity. Furthermore, tamoxifen and fulvestrant, known GPER agonist, also increased CRC STS activity, with this effect inhibited by the GPER antagonist G15. These results suggest that CRC can take up and hydrolyze E 1 S, and that subsequent GPER stimulation increases STS activity in a potentially novel positive feedback loop. As elevated STS expression is associated with poor prognosis in CRC, these results suggest HRT, tamoxifen and fulvestrant may negatively impact CRC patient outcomes.

A series of new arylamide derivatives possessing terminal sulfonate or sulfamate moieties was designed and synthesized. The target compounds were tested for in vitro inhibitory effects against the steroid sulfatase (STS) enzyme in a cell-free assay system. The free sulfamate derivative 1j was the most active. It inhibited the enzymatic activity by 72.0% and 55.7% at 20μM and 10μM, respectively. Compound 1j was further tested for STS inhibition in JEG-3 placental carcinoma cells with high STS enzyme activity. It inhibited 93.9% of the enzyme activity in JEG-3 placental carcinoma cells at 20μM with an efficacy near to that of the well-established drug STX64 as reference. At 10μM, 1j inhibited 86.1% of the STS activity of JEG-3. Its IC50 value against the STS enzyme in JEG-3 cells was 0.421μM. Thus, 1j represents an attractive new non-steroidal lead for further optimization., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Prostate cancer is the primary cancer in males, with increasing global incidence rates making this malignancy a significant healthcare burden. Androgens not only promote normal prostate maturity but also influence the development and progression of prostate cancer. Intriguingly, evidence now suggests endogenous and exogenous oestrogens, in the form of phytoestrogens, may be equally as relevant as androgens in prostate cancer growth. The prostate gland has the molecular mechanisms, catalysed by steroid sulphatase (STS), to unconjugate and utilise circulating oestrogens. Furthermore, prostate tissue also expresses enzymes essential for local oestrogen metabolism, including aromatase (CYP19A1) and 3β- and 17β-hydroxysteroid dehydrogenases. Increased expression of these enzymes in malignant prostate tissue compared with normal prostate indicates that oestrogen synthesis is favoured in malignancy and thus may influence tumour progression. In contrast to previous reviews, here we comprehensively explore the epidemiological and scientific evidence on how oestrogens impact prostate cancer, particularly focusing on pre-receptor oestrogen metabolism and subsequent molecular action. We analyse how molecular mechanisms and metabolic pathways involved in androgen and oestrogen synthesis intertwine to alter prostate tissue. Furthermore, we speculate on whether oestrogen receptor status in the prostate affects progression of this malignancy., (© 2016 Society for Endocrinology.)

Tumor neo-angiogenesis is regulated, in part, by the hypoxia-inducible gene HIF1. Evidence suggests HIF1 associates with polymerized microtubules and traffics to the nucleus. This study investigated the role of HIF1 in mediating the antitumor activity of two steroid-based sulfamate ester microtubule disruptors, STX140 and STX243, in vitro and in vivo. The effects of STX140, STX243 and the parental compound 2-methoxyestradiol (STX66) on HIF1α and HIF2α protein expression were assessed in vitro in MCF-7 and MDA-MB-231 cells cultured under hypoxia. More pertinently, their effects were examined on HIF1-regulated genes in vivo in mice bearing MCF-7 or MDA-MB-231 tumors. The level of mRNA expression of vascular endothelial growth factor (VEGF), glucose transporter 1 (GLUTI), phosphoglycerate kinase (PGK), ATP-binding cassette sub-family B member 1 (ABCB1) and carbonic anhydrase IX (CAIX) was quantified by Real-time Polymerase Chain Reaction (RT-PCR). Despite inhibiting nuclear HIF1α protein accumulation under hypoxia in vitro, STX140 and STX243 did not significantly regulate the expression of four out of five HIF1α-regulated genes in vitro and in vivo. Only CAIX mRNA expression was down-regulated both in vitro and in vivo. Immunoblot analysis showed that STX140 and STX243 reduced CAIX protein expression in vitro. These compounds had no effect on HIF2α translocation. The potential for inhibition of CAIX by STX140 and STX243 was examined by docking the ligands to the active site in comparison with a known sulfamate-based inhibitor. Microtubule disruption and antitumor activity of STX140 and STX243 is most likely HIF1-independent and may, at least in part, be mediated by inhibition of CAIX expression and activity., (Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Steroid sulfation and desulfation are fundamental pathways vital for a functional vertebrate endocrine system. After biosynthesis, hydrophobic steroids are sulfated to expedite circulatory transit. Target cells express transmembrane organic anion-transporting polypeptides that facilitate cellular uptake of sulfated steroids. Once intracellular, sulfatases hydrolyze these steroid sulfate esters to their unconjugated, and usually active, forms. Because most steroids can be sulfated, including cholesterol, pregnenolone, dehydroepiandrosterone, and estrone, understanding the function, tissue distribution, and regulation of sulfation and desulfation processes provides significant insights into normal endocrine function. Not surprisingly, dysregulation of these pathways is associated with numerous pathologies, including steroid-dependent cancers, polycystic ovary syndrome, and X-linked ichthyosis. Here we provide a comprehensive examination of our current knowledge of endocrine-related sulfation and desulfation pathways. We describe the interplay between sulfatases and sulfotransferases, showing how their expression and regulation influences steroid action. Furthermore, we address the role that organic anion-transporting polypeptides play in regulating intracellular steroid concentrations and how their expression patterns influence many pathologies, especially cancer. Finally, the recent advances in pharmacologically targeting steroidogenic pathways will be examined.

CD19 is ubiquitously expressed on chronic lymphocytic leukemia (CLL) cells and is therefore an attractive candidate for antibody targeting. XmAb5574 (aka MOR00208) is a novel humanized CD19 monoclonal antibody with an engineered Fc region to enhance Fcγ receptor binding affinity. Here we report results of a first in human phase 1 trial of XmAb5574 in patients with relapsed or refractory CLL. Twenty-seven patients were enrolled to 6 escalating dose levels, with expansion at the highest dose level of 12 mg/kg. Nine doses of XmAb5574 were infused over 8 weeks. No maximal tolerated dose was reached, and the drug was generally well tolerated, with infusion reactions of grades 1 and 2 being the most common toxicities. Grade 3 and 4 toxicities occurred in 5 patients and included neutropenia, thrombocytopenia, increased aspartate aminotransferase, febrile neutropenia, and tumor lysis syndrome. XmAb5574 showed preliminary efficacy, with 18 patients (66.7%) responding by physical examination criteria and laboratory studies, and 8 patients (29.6%) responding by computed tomography criteria. Pharmacokinetics showed a half-life of 14 days with clearance that was not dose-dependent. In conclusion, this phase 1 trial demonstrates safety and preliminary efficacy of a novel Fc-engineered CD19 monoclonal antibody XmAb5574 and justifies movement into the phase 2 setting. This trial was registered at www.clinicaltrials.gov as #NCT01161511., (© 2014 by The American Society of Hematology.)

Background: STX2484 is a novel non-steroidal compound with potent anti-proliferative activity. These studies aimed to identify STX2484's mechanism of action, in vivo efficacy and activity in taxane-resistant breast cancer models., Methods: Effects of STX2484 and paclitaxel on proliferation, cell cycle and apoptosis were assessed in vitro in drug-resistant (MCF-7(DOX)) and non-resistant cells (MCF-7(WT)). STX2484 efficacy in βIII tubulin overexpression in MCF-7 cells was also determined. Anti-angiogenic activity was quantified in vitro by a co-culture model and in vivo using a Matrigel plug assay. An MDA-MB-231 xenograft model was used to determine STX2484 efficacy in vivo., Results: STX2484 is a tubulin disruptor, which induces p53 expression, Bcl2 phosphorylation, caspase-3 cleavage, cell cycle arrest and apoptosis. In addition, STX2484 is a potent anti-angiogenic agent in vitro and in vivo. In breast cancer xenografts, STX2484 (20 mg kg(-1) p.o.) suppressed tumour growth by 84% after 35 days of daily dosing, with limited toxicity. In contrast to paclitaxel, STX2484 efficacy was unchanged in two clinically relevant drug-resistant models., Conclusions: STX2484 is an orally bioavailable microtubule-disrupting agent with in vivo anti-angiogenic activity and excellent in vivo efficacy with no apparent toxicity. Crucially, STX2484 has superior efficacy to paclitaxel in models of clinical drug resistance.

Despite paclitxael's clinical success, treating hormone-refractory breast cancer remains challenging. Paclitaxel has a poor pharmacological profile, characterized by a low therapeutic index (TIX) caused by severe dose limiting toxicities, such as neutropenia and peripheral neuropathy. Consequently, new drugs are urgently required. STX140, a compound previously shown to have excellent efficacy against many tumors, is here compared to paclitaxel in three translational in vivo breast cancer models, a rat model of peripheral neuropathy, and through pharmacological testing. Three different in vivo mouse models of breast cancer were used; the metastatic 4T1 orthotopic model, the C3(1)/SV40 T-Ag model, and the MDA-MB-231 xenograft model. To determine TIX and pharmacological profile of STX140, a comprehensive dosing regime was performed in mice bearing MDA-MD-231 xenografts. Finally, peripheral neuropathy was examined using a rat plantar thermal hyperalgesia model. In the 4T1 metastatic model, STX140 and paclitaxel significantly inhibited primary tumor growth and lung metastases. All C3(1)/SV40 T-Ag mice in the control and paclitaxel treated groups developed palpable mammary cancer. STX140 blocked 47% of tumors developing and significantly inhibited growth of tumors that did develop. STX140 treatment caused a significant (P<0.001) survival advantage for animals in early and late intervention groups. Conversely, in C3(1)/SV40 T-Ag mice, paclitaxel failed to inhibit tumor growth and did not increase survival time. Furthermore, paclitaxel, but not STX140, induced significant peripheral neuropathy and neutropenia. These results show that STX140 has a greater anti-cancer efficacy, TIX, and reduced neurotoxicity compared to paclitaxel in C3(1)/SV40 T-Ag mice and therefore may be of significant benefit to patients with breast cancer.

Aim: The role of oestrogen metabolism and action in colorectal cancer (CRC) is controversial. An extensive review of the current literature, encompassing epidemiological evidence, systemic and peripheral oestrogen concentrations, 17β-hydroxysteroid dehydrogenase (17β-HSD) and aromatase in CRC, steroid sulphatase (STS)/oestrone sulphotransferase (EST) and in vitro and in vivo genomic effects was therefore undertaken., Methods: A literature search (key words: colorectal cancer, oestrogen, oestrogen receptor, 17β-HSD, STS, organic anion transporter) was performed using Embase, Medline, and Pubmed and papers were evaluated on scientific relevance on an individual basis., Results: Epidemiological data highlights that premenopausal women, or postmenopausal women taking hormone replacement therapy, are significantly less likely than males to develop CRC. This implies that oestrogen signalling is most likely involved in CRC physiology and aetiology. Little is known about oestrogen metabolism in the colon. However, the expression of 17β-HSD, STS, and EST, enzymes involved in oestrogen metabolism, have shown prognostic significance. Evidence also suggests that protective effects are modulated through oestrogen receptor beta, although which metabolite of oestrogen, oestradiol (E2) or oestrone (E1), is more active remains undefined. To complicate matters, the changes in the peripheral ratios of these enzymes, oestrogens and receptors most likely influences CRC progression., Conclusion: Epidemiological evidence, now supported by in vitro and in vivo studies, strongly associates oestrogen action and metabolism with CRC. Initially protective against CRC, once developed, results suggests that oestrogens increase proliferation. Consequently, hormone-ablation therapy, already successful against breast and prostate cancer, may be effective against CRC.