Molecular characteristics of early-onset pancreatic ductal adenocarcinoma.

The median age of patients with pancreatic ductal adenocarcinoma (PDAC) at diagnosis is 71 years; however, around 10% present with early-onset pancreatic cancer (EOPC), i.e., before age 50. The molecular mechanisms underlying such an early onset are unknown. We assessed the role of common PDAC drivers (KRAS, TP53, CDKN2A and SMAD4) and determined their mutational status and protein expression in 90 formalin-fixed, paraffin-embedded tissues, including multiple primary and matched metastases, from 37 EOPC patients. KRAS was mutated in 88% of patients; p53 was altered in 94%, and p16 and SMAD4 were lost in 86% and 71% of patients, respectively. Meta-synthesis showed a higher rate of p53 alterations in EOPC than in late-onset PDAC (94% vs. 69%, P = 0.0009) and significantly higher loss of SMAD4 (71% vs. 44%, P = 0.0025). The majority of EOPC patients accumulated aberrations in all four drivers; in addition, high tumour heterogeneity was observed across all tissues. The cumulative effect of an exceptionally high rate of alterations in all common PDAC driver genes combined with high tumour heterogeneity suggests an important mechanism underlying the early onset of PDAC.

High grade urothelial carcinoma in kidney transplant patients with a history of BK viremia - Just a coincidence?

INTRODUCTION: Kidney transplant recipients (KTR) have a three-to-four-fold increased risk of developing urothelial carcinoma (UC) compared to the general population. BK polyoma virus (BKV) infection is known to affect approximately 15% of KTR. In vitro models support a potential pathogenic role for BKV in the development of UC. We describe a series of UC in kidney transplant recipients. METHODS: Electronic patient records were searched to identify KTR with UC who had undergone kidney only or simultaneous kidney and pancreas transplantation in a single UK center between 2009 and 2015. Where available, stored pathological samples were retrieved, re-examined and stained for SV40 as a marker of BKV using standard staining protocols for kidney biopsy samples. RESULTS: Fourteen KTR had developed UC post-transplant. Of these, 10 KTR had a history of BKV infection post-transplant. Six of these 10 KTR developed a rare micropapillary tumor subtype of UC which is typically only found in <1% of UC cases. All six micropapillary tumor samples stained positive for SV40, including samples from metastases. Three tumor samples were available from the four KTR with no history of BKV infection and were not micropapillary subtype and were negative for SV40. Three micropapillary tumors from immunocompetent patients were examined as controls and were negative for SV40. CONCLUSIONS: These findings would support a pathogenic role for BK virus in the development of rare micropapillary subtype urothelial tumors in the kidney transplant population.

Computational homogenization of histological microstructures in human prostate tissue: Heterogeneity, anisotropy and tension-compression asymmetry.

Human prostatic tissue exhibits complex mechanical behaviour due to its multiphasic, heterogeneous nature, with hierarchical microstructures involving epithelial compartments, acinar lumens and stromal tissue all interconnected in complex networks. This study aims to establish a computational homogenization framework for quantifying the mechanical behaviour of prostate tissue, considering its multiphasic heterogeneous microstructures and the mechanical characteristics of tissue constituents. Representative tissue microstructure models were reconstructed from high-resolution histology images. Parametric studies on the mechanical properties of the tissue constituents, particularly the fibre-reinforced hyper-elasticity of the stromal tissue, were carried out to investigate their effects on the apparent tissue properties. These were then benchmarked against the experimental data reported in literature. Results showed significant anisotropy, both structural and mechanical, and tension-compression asymmetry of the apparent behaviours of the prostatic tissue. Strong correlation with the key microstructural indices such as area fractions of tissue constituents and the tissue fabric tensor was also observed. The correlation between the stromal tissue orientation and the principal directions of the apparent properties suggested an essential role of stromal tissue in determining the directions of anisotropy and the compression-tension asymmetry characteristics in normal human prostatic tissue. This work presented a homogenization and histology-based computational approach to characterize the apparent mechanical behaviours of human prostatic or other similar glandular tissues, with the ultimate aim of assessing how pathological conditions (e.g., prostate cancer and benign prostatic hyperplasia) could affect the tissue mechanical properties in a future study.

THEM6-mediated reprogramming of lipid metabolism supports treatment resistance in prostate cancer.

Despite the clinical benefit of androgen-deprivation therapy (ADT), the majority of patients with advanced prostate cancer (PCa) ultimately develop lethal castration-resistant prostate cancer (CRPC). In this study, we identified thioesterase superfamily member 6 (THEM6) as a marker of ADT resistance in PCa. THEM6 deletion reduces in vivo tumour growth and restores castration sensitivity in orthograft models of CRPC. Mechanistically, we show that the ER membrane-associated protein THEM6 regulates intracellular levels of ether lipids and is essential to trigger the induction of the ER stress response (UPR). Consequently, THEM6 loss in CRPC cells significantly alters ER function, reducing de novo sterol biosynthesis and preventing lipid-mediated activation of ATF4. Finally, we demonstrate that high THEM6 expression is associated with poor survival and correlates with high levels of UPR activation in PCa patients. Altogether, our results highlight THEM6 as a novel driver of therapy resistance in PCa as well as a promising target for the treatment of CRPC.

Analysis of Prostate Cancer Tumor Microenvironment Identifies Reduced Stromal CD4 Effector T-cell Infiltration in Tumors with Pelvic Nodal Metastasis.

BACKGROUND: Pelvic nodal metastasis in prostate cancer impacts patient outcome negatively. OBJECTIVE: To explore tumor-infiltrating immune cells as a potential predictive tool for regional lymph node (LN) metastasis. DESIGN SETTING AND PARTICIPANTS: We applied multiplex immunofluorescence and targeted transcriptomic analysis on 94 radical prostatectomy specimens in patients with (LN+) or without (LN-) pelvic nodal metastases. Both intraepithelial and stromal infiltrations of immune cells and differentially expressed genes (mRNA and protein levels) were correlated with the nodal status. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The identified CD4 effector cell signature of nodal metastasis was validated in a comparable independent patient cohort of 184 informative cases. Patient outcome analysis and decision curve analysis were performed with the CD4 effector cell density-based signature. RESULTS AND LIMITATIONS: In the discovery cohort, both tumor epithelium and stroma from patients with nodal metastasis had significantly lower infiltration of multiple immune cell types, with stromal CD4 effector cells highlighted as the top candidate marker. Targeted gene expression analysis and confirmatory protein analysis revealed key alteration of extracellular matrix components in tumors with nodal metastasis. Of note, stromal CD4 immune cell density was a significant independent predictor of LN metastasis (odds ratio [OR] = 0.15, p = 0.004), and was further validated as a significant predictor of nodal metastasis in the validation cohort (OR = 0.26, p < 0.001). CONCLUSIONS: Decreased T-cell infiltrates in the primary tumor (particularly CD4 effector cells) are associated with a higher risk of LN metastasis. Future evaluation of CD4-based assays on prostate cancer diagnostic biopsy materials may improve selection of at-risk patients for the treatment of LN metastasis. PATIENT SUMMARY: In this report, we found that cancer showing evidence of cancer metastasis to the lymph nodes tends to have less immune cells present within the tumor. We conclude that the extent of immune cells present within a prostate tumor can help doctors determine the most appropriate treatment plan for individual patients.

SLFN5 Regulates LAT1-Mediated mTOR Activation in Castration-Resistant Prostate Cancer.

Androgen deprivation therapy (ADT) is the standard of care for treatment of nonresectable prostate cancer. Despite high treatment efficiency, most patients ultimately develop lethal castration-resistant prostate cancer (CRPC). In this study, we performed a comparative proteomic analysis of three in vivo, androgen receptor (AR)-responsive orthograft models of matched hormone-naïve prostate cancer and CRPC. Differential proteomic analysis revealed that distinct molecular mechanisms, including amino acid (AA) and fatty acid metabolism, are involved in the response to ADT in the different models. Despite this heterogeneity, Schlafen family member 5 (SLFN5) was identified as an AR-regulated protein in CRPC. SLFN5 expression was high in CRPC tumors and correlated with poor patient outcome. In vivo, SLFN5 depletion strongly impaired tumor growth in castrated conditions. Mechanistically, SLFN5 interacted with ATF4 and regulated the expression of LAT1, an essential AA transporter. Consequently, SLFN5 depletion in CRPC cells decreased intracellular levels of essential AA and impaired mTORC1 signaling in a LAT1-dependent manner. These results confirm that these orthograft models recapitulate the high degree of heterogeneity observed in patients with CRPC and further highlight SLFN5 as a clinically relevant target for CRPC. SIGNIFICANCE: This study identifies SLFN5 as a novel regulator of the LAT1 amino acid transporter and an essential contributor to mTORC1 activity in castration-resistant prostate cancer.

2,4-dienoyl-CoA reductase regulates lipid homeostasis in treatment-resistant prostate cancer.

Despite the clinical success of Androgen Receptor (AR)-targeted therapies, reactivation of AR signalling remains the main driver of castration-resistant prostate cancer (CRPC) progression. In this study, we perform a comprehensive unbiased characterisation of LNCaP cells chronically exposed to multiple AR inhibitors (ARI). Combined proteomics and metabolomics analyses implicate an acquired metabolic phenotype common in ARI-resistant cells and associated with perturbed glucose and lipid metabolism. To exploit this phenotype, we delineate a subset of proteins consistently associated with ARI resistance and highlight mitochondrial 2,4-dienoyl-CoA reductase (DECR1), an auxiliary enzyme of beta-oxidation, as a clinically relevant biomarker for CRPC. Mechanistically, DECR1 participates in redox homeostasis by controlling the balance between saturated and unsaturated phospholipids. DECR1 knockout induces ER stress and sensitises CRPC cells to ferroptosis. In vivo, DECR1 deletion impairs lipid metabolism and reduces CRPC tumour growth, emphasizing the importance of DECR1 in the development of treatment resistance.

Activation of ß-Catenin Cooperates with Loss of Pten to Drive AR-Independent Castration-Resistant Prostate Cancer.

Inhibition of the androgen receptor (AR) is the main strategy to treat advanced prostate cancers. AR-independent treatment-resistant prostate cancer is a major unresolved clinical problem. Patients with prostate cancer with alterations in canonical WNT pathway genes, which lead to ß-catenin activation, are refractory to AR-targeted therapies. Here, using clinically relevant murine prostate cancer models, we investigated the significance of ß-catenin activation in prostate cancer progression and treatment resistance. ß-Catenin activation, independent of the cell of origin, cooperated with Pten loss to drive AR-independent castration-resistant prostate cancer. Prostate tumors with ß-catenin activation relied on the noncanonical WNT ligand WNT5a for sustained growth. WNT5a repressed AR expression and maintained the expression of c-Myc, an oncogenic effector of ß-catenin activation, by mediating nuclear localization of NFκBp65 and ß-catenin. Overall, WNT/ß-catenin and AR signaling are reciprocally inhibited. Therefore, inhibiting WNT/ß-catenin signaling by limiting WNT secretion in concert with AR inhibition may be useful for treating prostate cancers with alterations in WNT pathway genes. SIGNIFICANCE: Targeting of both AR and WNT/ß-catenin signaling may be required to treat prostate cancers that exhibit alterations of the WNT pathway.

Correction: BRF1 accelerates prostate tumourigenesis and perturbs immune infiltration.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Spectrum of Melanocytic Proliferation/Differentiation in a Large Series of Cutaneous Neurofibromas: An Under-Recognized Histopathologic Phenomenon and Potential Clue for Neurofibromatosis Type 1.

AIMS: Neurofibromas (NFs) and melanocytic nevi share a common neuroectodermal origin and may occasionally show overlapping morphological features. The objective of this study was to assess the prevalence and spectrum of melanocytic proliferation/differentiation in NFs and also to test the hypothesis whether detection of this feature could be used as a potential clue for neurofibromatosis type 1 (NF-1). METHODS: This was a retrospective study of 229 syndromic and 239 sporadic cutaneous NFs. Each case was assessed for an associated melanocytic component, both within the tumor and the overlying epidermis. Melan A immunohistochemistry was used in selected cases to further characterize this feature, particularly in diffuse NFs. RESULTS: An associated melanocytic component was detected in 77/229 syndromic and 12/239 sporadic cases (P < 0.00001). This was in the form of a junctional proliferation (lentiginous melanocytic hyperplasia or junctional nevus) or dermal differentiation (diffuse spindle cell or dermal nests of pigmented epithelioid melanocytes). CONCLUSIONS: Our study affirms that the spectrum of melanocytic proliferation/differentiation in NFs is broad and probably under-recognized. Awareness of this phenomenon is critical to avoid misdiagnosis of some diffuse NFs as primary melanocytic tumors, for example, desmoplastic melanomas. Given the strong link between dermal melanocytic differentiation and syndromic NFs, its detection could potentially serve as a useful clue for NF-1 in an appropriate clinical context.

BRF1 accelerates prostate tumourigenesis and perturbs immune infiltration.

BRF1 is a rate-limiting factor for RNA Polymerase III-mediated transcription and is elevated in numerous cancers. Here, we report that elevated levels of BRF1 associate with poor prognosis in human prostate cancer. In vitro studies in human prostate cancer cell lines demonstrated that transient overexpression of BRF1 increased cell proliferation whereas the transient downregulation of BRF1 reduced proliferation and mediated cell cycle arrest. Consistent with our clinical observations, BRF1 overexpression in a Pten-deficient mouse (PtenΔ/Δ BRF1Tg) prostate cancer model accelerated prostate carcinogenesis and shortened survival. In PtenΔ/Δ BRF1Tg tumours, immune and inflammatory processes were altered, with reduced tumoral infiltration of neutrophils and CD4 positive T cells, which can be explained by decreased levels of complement factor D (CFD) and C7 components of the complement cascade, an innate immune pathway that influences the adaptive immune response. We tested if the secretome was involved in BRF1-driven tumorigenesis. Unbiased proteomic analysis on BRF1-overexpresing PC3 cells confirmed reduced levels of CFD in the secretome, implicating the complement system in prostate carcinogenesis. We further identify that expression of C7 significantly correlates with expression of CD4 and has the potential to alter clinical outcome in human prostate cancer, where low levels of C7 associate with poorer prognosis.

Demographic, clinical, and pathological features of early onset pancreatic cancer patients.

BACKGROUND: Early onset pancreatic cancer (EOPC), i.e. pancreatic ductal adenocarcinoma (PDAC) occurring in patients below 50 years of age, is rare and there is limited information regarding risk factors, molecular basis and outcome. This study aimed to determine the demographic and clinicopathological features and survival figures for EOPC. METHODS: A retrospective analysis of patients treated at the Royal London Hospital for PDAC between September 2004 and September 2015 was performed. Data on demographics, risk factors, presentation, pathological features, treatment and survival outcome were compared in EOPC and older PDAC patients. RESULTS: Of 369 PDAC cases identified, 35 (9.5%) were EOPC. Compared to older patients, EOPC patients were more frequently male (71% vs 54%, p = 0.043) and less commonly of British origin (37% vs 70%, p = 0.002). There was no significant difference regarding the prevalence of any of the risk factors known to be associated with older PDAC patients. Fewer EOPC patients presented with resectable disease (23% vs 44%, p = 0.015) and more received adjuvant chemo/radiotherapy (60% vs 46%, p = 0.008). The overall median survival and stage specific survival did not differ significantly between the two groups, although a longer survival for localized disease was seen in EOPC patients (25 months (12.9-37, 95%CI) vs 13 months (10.5-15.5 95%CI) for older PDAC patients). CONCLUSIONS: The EOPC patients had different demographics and were more likely than their older PDAC counterparts to be male. Typically they presented with more advanced disease, received more aggressive treatment, and had on overall similar survival outcome.

X-rays for Acute Knee Injuries: Pre- and Post- Pittsburgh Decision Rules Implementation. A District General Hospital Experience.

BACKGROUND: We wanted to assess the number of unnecessary radiographs done for acute knee injury patients and the accuracy of the Pittsburgh decision rules. MATERIAL AND METHODS: A retrospective observational study was done to look at the acute knee injury patients presented to a district general hospital Accident and Emergency Department from August 2011 till August 2013. We assessed the following parameters: sex, age, mechanism of injury, weight-bearing status and incidence of fractures in patients subjected to plain radiograph. A prospective study was then done from April 2014- August 2014 following implementation of the Pittsburgh decision rules. RESULTS: 24% of the patients had knee X-ray, compared to 72.12% in the first cycle. 36.8% had fracture, compared to 6.1% first cycle, with 66.7 % reduction in x-rays. Pittsburgh decision rules sensitivity was 100% and specificity 85.3%, positive predictive value 45.8% and accuracy 87%. CONCLUSIONS: 1. The Pittsburgh decision rules is highly sensitive, specific and accurate in determining the need of X-ray in acute knee Injuries. 2. We found that the Pittsburgh decision rules performs well in our hospital, which coincides with previously published literature.

The quality of reporting of randomised controlled trials in asthma: a systematic review.

BACKGROUND: There are concerns about the reporting quality of asthma trials. AIMS: To describe the reporting of contemporary asthma trials and to identify factors associated with better reporting quality. METHODS: Two reviewers independently searched MEDLINE for randomised controlled trials (RCTs) of asthma published between January 2010 and July 2012 in leading generalist and specialist journals. We calculated the proportion of trials that adequately reported each Consolidated Standards of Reporting Trials (CONSORT) checklist item and an overall quality score for each trial. Factors associated with better reporting quality were investigated. RESULTS: Thirty-five RCTs satisfied our eligibility criteria. Four trials adequately reported <50% of the items, 15 adequately reported 50-60% of items, and 16 adequately reported >60% of items. Seventeen of the 38 CONSORT items were consistently well reported in more than two-thirds of the articles. In contrast, nine items were poorly reported in more than half the trials - namely, identification as a randomised trial in the title (40.0%), an adequate structured summary/abstract (48.6%), details of eligibility criteria (34.3%), recruitment (48.6%), randomisation procedures (22.9%), intervention (38.5%), harms (34.3%), the funding source (45.7%), and access to the full trial protocol (17.1%). Studies led by teams in high-income country settings were associated with better quality of reporting (relative risk=1.33, 95% CI 1.09 to 1.64). CONCLUSIONS: The quality of reporting in contemporary asthma literature remains suboptimal. We have identified important areas in which reporting quality needs to be improved.