11 research outputs found

    Clinical and pathological associations of PTEN expression in ovarian cancer: a multicentre study from the Ovarian Tumour Tissue Analysis Consortium

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    Abstract: Background: PTEN loss is a putative driver in histotypes of ovarian cancer (high-grade serous (HGSOC), endometrioid (ENOC), clear cell (CCOC), mucinous (MOC), low-grade serous (LGSOC)). We aimed to characterise PTEN expression as a biomarker in epithelial ovarian cancer in a large population-based study. Methods: Tumours from 5400 patients from a multicentre observational, prospective cohort study of the Ovarian Tumour Tissue Analysis Consortium were used to evaluate associations between immunohistochemical PTEN patterns and overall survival time, age, stage, grade, residual tumour, CD8+ tumour-infiltrating lymphocytes (TIL) counts, expression of oestrogen receptor (ER), progesterone receptor (PR) and androgen receptor (AR) by means of Cox proportional hazard models and generalised Cochran–Mantel–Haenszel tests. Results: Downregulation of cytoplasmic PTEN expression was most frequent in ENOC (most frequently in younger patients; p value = 0.0001) and CCOC and was associated with longer overall survival in HGSOC (hazard ratio: 0.78, 95% CI: 0.65–0.94, p value = 0.022). PTEN expression was associated with ER, PR and AR expression (p values: 0.0008, 0.062 and 0.0002, respectively) in HGSOC and with lower CD8 counts in CCOC (p value < 0.0001). Heterogeneous expression of PTEN was more prevalent in advanced HGSOC (p value = 0.019) and associated with higher CD8 counts (p value = 0.0016). Conclusions: PTEN loss is a frequent driver in ovarian carcinoma associating distinctly with expression of hormonal receptors and CD8+ TIL counts in HGSOC and CCOC histotypes

    Combining two-directional synthesis and tandem reactions, part 11: second generation syntheses of (±)-hippodamine and (±)-epi-hippodamine

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    Background<p>Hippodamine is a volatile defence alkaloid isolated from ladybird beetles which holds potential as an agrochemical agent and was the subject of a synthesis by our group in 2005.</p><p>Results</p><p>Two enhancements to our previous syntheses of (±)-hippodamine and (±)-epi-hippodamine are presented which are able to shorten the syntheses by up to two steps.</p><p>Conclusions</p><p>Key advances include a two-directional homologation by cross metathesis and a new tandem reductive amination / double intramolecular Michael addition which generates 6 new bonds, 2 stereogenic centres and two rings, giving a single diastereomer in 74% yield.</p

    Efficient Syntheses of AZD4407 via Thioether Formation by Nucleophilic Attack of Organometallic Species on Sulphur

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    The development of two efficient strategies for the synthesis of AZD4407 is reported, both of which are considered suitable for large-scale manufacture. In the first approach, 3-bromothiophene is coupled with (2S)-2-methyltetrahydropyran-4- one using Grignard chemistry. Following hydroxyl protection and lithiation at thiophene C-2, reaction with a protected 5-mercapto-1-methyl 1,3-dihydro-indol-2-one derivative bearing a leaving group on sulphur provides AZD4407 after acid- catalysed deprotection and epimerisation. The second approach starts from 2,4-dibromothiophene, which undergoes a selective Grignard exchange reaction at C-2 followed by reaction with similar protected mercapto-oxindole derivatives. Reprotection of the oxindole ring, followed by a second Grignard exchange, and reaction with (2S)-2-methyltetrahydropyran-4-one provides AZD4407 after acid-catalysed deprotection and epimerisation
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