HR‐MAS MRS of the pancreas reveals reduced lipid and elevated lactate and taurine associated with early pancreatic cancer

The prognosis for patients with pancreatic cancer is extremely poor, as evidenced by the disease's five‐year survival rate of ~5%. New approaches are therefore urgently needed to improve detection, treatment, and monitoring of pancreatic cancer. MRS‐detectable metabolic changes provide useful biomarkers for tumor detection and response‐monitoring in other cancers. The goal of this study was to identify MRS‐detectable biomarkers of pancreatic cancer that could enhance currently available imaging approaches. We used ¹H high‐resolution magic angle spinning MRS to probe metabolite levels in pancreatic tissue samples from mouse models and patients. In mice, the levels of lipids dropped significantly in pancreata with lipopolysaccharide‐induced inflammation, in pancreata with pre‐cancerous metaplasia (4 week old p48‐Cre;LSL‐Kras^G12D mice), and in pancreata with pancreatic intraepithelial neoplasia, which precedes invasive pancreatic cancer (8 week old p48‐Cre LSL‐Kras^G12D mice), to 26 ± 19% (p = 0.03), 19 ± 16% (p = 0.04), and 26 ± 10% (p = 0.05) of controls, respectively. Lactate and taurine remained unchanged in inflammation and in pre‐cancerous metaplasia but increased significantly in pancreatic intraepithelial neoplasia to 266 ± 61% (p = 0.0001) and 999 ± 174% (p < 0.00001) of controls, respectively. Importantly, analysis of patient biopsies was consistent with the mouse findings. Lipids dropped in pancreatitis and in invasive cancer biopsies to 29 ± 15% (p = 0.01) and 26 ± 38% (p = 0.02) of normal tissue. In addition, lactate and taurine levels remained unchanged in inflammation but rose in tumor samples to 244 ± 155% (p = 0.02) and 188 ± 67% (p = 0.02), respectively, compared with normal tissue. Based on these findings, we propose that a drop in lipid levels could serve to inform on pancreatitis and cancer‐associated inflammation, whereas elevated lactate and taurine could serve to identify the presence of pancreatic intraepithelial neoplasia and invasive tumor. Our findings may help enhance current imaging methods to improve early pancreatic cancer detection and monitoring. Copyright © 2014 John Wiley & Sons, Ltd.     

A quantitative comparison of metabolite signals as detected by in vivo MRS with ex vivo 1H HR‐MAS for childhood brain tumours

¹H MRS provides a powerful method for investigating tumour metabolism by allowing the measurement of metabolites in vivo. Recently, the technique of ¹H high‐resolution magic angle spinning (HR‐MAS) has been shown to produce high‐quality data, allowing the accurate measurement of many metabolites present in unprocessed biopsy tissue. The purpose of this study was to evaluate the agreement between the techniques of in vivo MRS and ex vivo HR‐MAS for investigating childhood brain tumours. Short‐TE (30 ms), single‐voxel, in vivo MRS was performed on 16 paediatric patients with brain tumours at 1.5 T. A frozen biopsy sample was available for each patient. HR‐MAS was performed on the biopsy samples, and metabolite quantities were determined from the MRS and HR‐MAS data using the LCModel? and TARQUIN algorithms, respectively. Linear regression was performed on the metabolite quantities to asses the agreement between MRS and HR‐MAS. Eight of the 12 metabolite quantities were found to correlate significantly (P < 0.05). The four worst correlating metabolites were aspartate, scyllo‐inositol, glycerophosphocholine and N‐acetylaspartate, and, except for glycerophosphocholine, this error was reflected in their higher Cramer–Rao lower bounds (CRLBs), suggesting that low signal‐to‐noise was the greatest source of error for these metabolites. Glycerophosphocholine had a lower CRLB implying that interference with phosphocholine and choline was the most significant source of error. The generally good agreement observed between the two techniques suggests that both MRS and HR‐MAS can be used to reliably estimate metabolite quantities in brain tumour tissue and that tumour heterogeneity and metabolite degradation do not have an important effect on the HR‐MAS metabolite profile for the tumours investigated. HR‐MAS can be used to improve the analysis and understanding of MRS data. Copyright © 2009 John Wiley & Sons, Ltd.     

1H and 13C HR-MAS spectroscopy of intact biopsy samples ex vivo and in vivo 1H MRS study of human high grade gliomas

High-resolution magic angle spinning (HR-MAS) one- and two-dimensional 1H and 13C nuclear magnetic resonance (NMR) spectroscopy has been used to study intact glioblastoma (GBM) brain tumour tissue. The results were compared with in vitro chemical extract and in vivo spectra. The resolution of 1H one-dimensional, 1H TOCSY and 13C HSQC HR-MAS spectra is comparable to that obtained on perchloric extracts. 13C HSQC HR-MAS spectra have been particularly useful for the identification of 37 different metabolites in intact biopsy tumours, excluding water and DSS components. To our knowledge, this is the most detailed assignment of biochemical compounds obtained in intact human tissue, in particular in brain tumour tissue. Tissue degradation during the recording of the NMR experiment was avoided by keeping the sample at a temperature of 4 degrees C. Detailed metabolical compositions of 10 GBM (six primary, two secondary and two unclassified) were obtained. A good correlation between ex vivo and in vivo MRS has been found.     

Detection of cancer in cervical tissue biopsies using mobile lipid resonances measured with diffusion‐weighted 1H magnetic resonance spectroscopy

The purpose of this study was to implement a diffusion‐weighted sequence for visualisation of mobile lipid resonances (MLR) using high resolution magic angle spinning (HR‐MAS) ¹H MRS and to evaluate its use in establishing differences between tissues from patients with cervical carcinoma that contain cancer from those that do not. A stimulated echo sequence with bipolar gradients was modified to allow T₁ and T₂ measurements and optimised by recording signal loss in HR‐MAS spectra as a function of gradient strength in model lipids and tissues. Diffusion coefficients, T₁ and apparent T₂ relaxation times were measured in model lipid systems. MLR profiles were characterised in relation to T₁ and apparent T₂ relaxation in human cervical cancer tissue samples. Diffusion‐weighted (DW) spectra of cervical biopsies were quantified and peak areas analysed using linear discriminant analysis (LDA). The optimised sequence reduced spectral overlap by suppressing signals originating from low molecular weight metabolites and non‐lipid contributions. Significantly improved MLR visualisation allowed visualisation of peaks at 0.9, 1.3, 1.6, 2.0, 2.3, 2.8, 4.3 and 5.3 ppm. MLR analysis of DW spectra showed at least six peaks arising from saturated and unsaturated lipids and those arising from triglycerides. Significant differences in samples containing histologically confirmed cancer were seen for peaks at 0.9 (p < 0.006), 1.3 (p < 0.04), 2.0 (p < 0.03), 2.8 (p < 0.003) and 4.3 ppm (p < 0.0002). LDA analysis of MLR peaks from DW spectra almost completely separated two clusters of cervical biopsies (cancer, ‘no‐cancer’), reflecting underlying differences in MLR composition. Generated Receiver Operating Characteristic (ROC) curves and calculated area under the curve (0.962) validated high sensitivity and specificity of the technique. Diffusion‐weighting of HR‐MAS spectroscopic sequences is a useful method for characterising MLR in cancer tissues and displays an accumulation of lipids arising during tumourigenesis and an increase in the unsaturated lipid and triglyceride peaks with respect to saturated MLR. Copyright © 2009 John Wiley & Sons, Ltd.     

Metabolic,pathologic, and genetic analysis of prostate tissues: quantitative evaluation of histopathologic and mRNA integrity after HR‐MAS spectroscopy

The impact of high‐resolution magic angle spinning (HR‐MAS) spectroscopy on the histopathologic and mRNA integrity of human prostate tissues was evaluated. Forty prostate tissues were harvested at transrectal ultrasound (TRUS) guided biopsy (n = 20) or radical prostatectomy surgery (n = 20), snap‐frozen on dry ice, and stored at ?80°C until use. Twenty‐one samples (n = 11 biopsy, n = 10 surgical) underwent HR‐MAS spectroscopy prior to histopathologic and cDNA microarray analysis, while 19 control samples (n = 9 biopsy, n = 10 surgical) underwent only histopathologic and microarray analysis. Frozen tissues were sectioned at 14‐µm intervals and placed on individual histopathology slides. Every 8th slide was stained with hematoxylin and eosin (H&E) and used to target areas of predominantly epithelial tissue on the remaining slides for mRNA integrity and cDNA microarray analysis. Histopathologic integrity was graded from 1 (best) to 5 (worst) by two ‘blinded’ pathologists. Histopathologic integrity scores were not significantly different for post‐surgical tissues (HR‐MAS vs controls); however, one pathologist's scores were significantly lower for biopsy tissues following HR‐MAS while the other pathologist's scores were not. mRNA integrity assays were performed using an Agilent 2100 Bioanalyzer and the electrophoretic traces were scored with an RNA integrity number (RIN) from 1 (degraded) to 10 (intact). RIN scores were not significantly different for surgical tissues, but were significantly lower for biopsy tissues following HR‐MAS spectroscopy. The isolated mRNA then underwent two rounds of amplification, conversion to cDNA, coupling to Cy3 and Cy5 dyes, microarray hybridization, imaging, and analysis. Significance analysis of microarrays (SAM) identified no significantly over‐ or under‐expressed genes, including 14 housekeeping genes, between HR‐MAS and control samples of surgical and biopsy tissues (5% false discovery rate). This study demonstrates that histopathologic and genetic microarray analysis can be successfully performed on prostate surgical and biopsy tissues following HR‐MAS analysis; however, biopsy tissues are more fragile than surgical tissues. Copyright © 2009 John Wiley & Sons, Ltd.     

Investigation of relative metabolic changes in the organs and plasma of rats exposed to X‐ray radiation using HR‐MAS 1H NMR and solution 1H NMR

Excess exposure to ionizing radiation generates reactive oxygen species and increases the cellular inflammatory response by modifying various metabolic pathways. However, an investigation of metabolic perturbations and organ‐specific responses based on the amount of radiation during the acute phase has not been conducted. In this study, high‐resolution magic‐angle‐spinning (HR‐MAS) NMR and solution NMR‐based metabolic profiling were used to investigate dose‐dependent metabolic changes in multiple organs and tissues – including the jejunum, spleen, liver, and plasma – of rats exposed to X‐ray radiation. The organs, tissues, and blood samples were obtained 24, 48, and 72 h after exposure to low‐dose (2 Gy) and high‐dose (6 Gy) X‐ray radiation and subjected to metabolite profiling and multivariate analyses. The results showed the time course of the metabolic responses, and many significant changes were detected in the high‐dose compared with the low‐dose group. Metabolites with antioxidant properties showed acute responses in the jejunum and spleen after radiation exposure. The levels of metabolites related to lipid and protein metabolism were decreased in the jejunum. In addition, amino acid levels increased consistently at all post‐irradiation time points as a consequence of activated protein breakdown. Consistent with these changes, plasma levels of tricarboxylic acid cycle intermediate metabolites decreased. The liver did not appear to undergo remarkable metabolic changes after radiation exposure. These results may provide insight into the major metabolic perturbations and mechanisms of the biological systems in response to pathophysiological damage caused by X‐ray radiation. Copyright © 2016 John Wiley & Sons, Ltd.     

Investigation of Templated Mesoporous Silicate Thin Films Using High Speed,Solid‐State 1H MAS and Double Quantum NMR Spectroscopy

Two‐dimensional DQ ¹H MAS NMR has been used the investigate the local structure of a surfactant‐templated silicate thin film prepared from adding 4% polyoxyethylene(10) cetyl ether to an acidic TEOS silica sol. A close spatial contact between the surfactant and the silicate present in these materials could be demonstrated, while the high sensitivity of the NMR experiments allowed systems with limited amounts of material to be investigated. The detected inorganic‐organic interactions in these materials provide additional information into the chemical processes occurring during the self‐assembly process and the formation of meso‐structured materials.

Graphical representation of the spatial interactions observed between the silanols, oxomethylene protons of the surfactant and water within the template silicate material.     

Characterization of metabolites in infiltrating gliomas using ex vivo 1H high‐resolution magic angle spinning spectroscopy

Gliomas are routinely graded according to histopathological criteria established by the World Health Organization. Although this classification can be used to understand some of the variance in the clinical outcome of patients, there is still substantial heterogeneity within and between lesions of the same grade. This study evaluated image‐guided tissue samples acquired from a large cohort of patients presenting with either new or recurrent gliomas of grades II–IV using ex vivo proton high‐resolution magic angle spinning spectroscopy. The quantification of metabolite levels revealed several discrete profiles associated with primary glioma subtypes, as well as secondary subtypes that had undergone transformation to a higher grade at the time of recurrence. Statistical modeling further demonstrated that these metabolomic profiles could be differentially classified with respect to pathological grading and inter‐grade conversions. Importantly, the myo‐inositol to total choline index allowed for a separation of recurrent low‐grade gliomas on different pathological trajectories, the heightened ratio of phosphocholine to glycerophosphocholine uniformly characterized several forms of glioblastoma multiforme, and the onco‐metabolite D‐2‐hydroxyglutarate was shown to help distinguish secondary from primary grade IV glioma, as well as grade II and III from grade IV glioma. These data provide evidence that metabolite levels are of interest in the assessment of both intra‐grade and intra‐lesional malignancy. Such information could be used to enhance the diagnostic specificity of in vivo spectroscopy and to aid in the selection of the most appropriate therapy for individual patients. © 2014 The Authors. NMR in Biomedicine published by John Wiley & Sons, Ltd.     

Assessment of early docetaxel response in an experimental model of human breast cancer using DCE‐MRI,ex vivo HR MAS,and in vivo 1H MRS

The purpose of this study was to evaluate the use of dynamic contrast‐enhanced (DCE) MRI, in vivo ¹H MRS and ex vivo high resolution magic angle spinning (HR MAS) MRS of tissue samples as methods to detect early treatment effects of docetaxel in a breast cancer xenograft model (MCF‐7) in mice. MCF‐7 cells were implanted subcutaneously in athymic mice and treated with docetaxel (20, 30, and 40 mg/kg) or saline six weeks later. DCE‐MRI and in vivo ¹H MRS were performed on a 7 T MR system three days after treatment. The dynamic images were used as input for a two‐compartment model, yielding the vascular parameters K^trans and v_e. HR MAS MRS, histology, and immunohistochemical staining for proliferation (Ki‐67), apoptosis (M30 cytodeath), and vascular/endothelial cells (CD31) were performed on excised tumor tissue. Both in vivo spectra and HR MAS spectra were used as input for multivariate analysis (principal component analysis (PCA) and partial least squares regression analysis (PLS)) to compare controls to treated tumors. Tumor growth was suppressed in docetaxel‐treated mice compared to the controls. The anti‐tumor effect led to an increase in K^trans and v_e values in all the treated groups. Furthermore, in vivo MRS and HR MAS MRS revealed a significant decrease in choline metabolite levels for the treated groups, in accordance with reduced proliferative index as seen on Ki‐67 stained sections. In this study DCE‐MRI, in vivo MRS and ex vivo HR MAS MRS have been used to demonstrate that docetaxel treatment of a human breast cancer xenograft model results in changes in the vascular dynamics and metabolic profile of the tumors. This indicates that these MR methods could be used to monitor intra‐tumoral treatment effects. Copyright © 2009 John Wiley & Sons, Ltd.     

Prognostic and radiographic correlates of a prospectively collected molecularly profiled cohort of IDH1/2‐wildtype astrocytomas

Background: In the molecular era, the relevance of tumor grade for prognostication of IDH1/2‐wildtype (WT) gliomas has been debated. It has been suggested that histologic grade II and III astrocytomas with molecular features of glioblastoma, IDH1/2‐WT have a similar prognosis to glioblastoma and should be considered for the same clinical trials. Methods: We integrated prospective clinical sequencing from 564 patients with IDH1/2‐WT gliomas (26 grade II, 71 grade III and 467 grade IV) with clinical and radiographic data to assess associations between molecular features, grade and outcome. Results: Compared to histologic grade IV IDH1/2‐WT astrocytomas, histologic grade II astrocytomas harbor fewer chromosome 7/10 alterations (P = 0.04), EGFR amplifications (P = 0.022) and alterations in cell‐cycle effectors (P = 1.9e‐11), but a similar frequency of TERT promoter mutations. In contrast, there is no difference in the frequency of these canonical molecular features in histologic grade III vs. IV IDH1/2‐WT disease. Progression‐free (PFS) and overall survival (OS) for histologic grade II tumors were significantly longer than grade III tumors (P = 0.02 and P = 0.008, respectively), whereas there was no difference in PFS and OS for histologic grade III compared to grade IV tumors. Median PFS for histologic grade II, III and IV tumors was 19, 11 and 9 months, respectively. Median OS for the same tumors was 44, 23 and 23 months, respectively. In histologic grade II and III IDH1/2 WT tumors, gliomatosis is associated with the absence of cell‐cycle alterations (P = 0.008) and enriched in grade II features (P = 0.1) and alterations in the PI3K‐AKT pathway (P = 0.09). Conclusions: Grade II histology has genotypic and phenotypic associations with prognostic implications in IDH1/2‐WT astrocytomas.     

Detection of human polyomavirus proteins,T‐antigen and agnoprotein,in human tumor tissue arrays

Expression of the human polyomavirus JCV genome in several experimental animals induces a variety of neural origin tumors. The viral proteins, T‐antigen and Agnoprotein, contribute to the oncogenesis of JCV by associating with several tumor suppressor proteins and dysregulating signaling pathways, which results in uncontrolled cell proliferation. In addition, T‐antigen and Agnoprotein have been associated with DNA damage and interfering with DNA repair mechanisms. In this study, we have utilized commercially available tissue arrays of human tumors of various origins and demonstrated the expression of both T‐antigen and Agnoprotein in some, but not all, tumors of neural and non‐neural origin. Most notably, more than 40% of human glioblastomas and greater than 30% of colon adenocarcinomas express viral proteins. The detection of viral transforming proteins, T‐antigen and Agnoprotein in the absence of viral capsid proteins suggests a role for JCV in the development and/or progression of human tumors. These results invite further large‐scale investigation on the role of polyomaviruses, particularly JCV in the pathogenesis of human cancer. J. Med. Virol. 82: 806–811, 2010. © 2010 Wiley‐Liss, Inc.     

Impact of intratumoral heterogeneity of breast cancer tissue on quantitative metabolomics using high‐resolution magic angle spinning 1H NMR spectroscopy

High‐resolution magic angle spinning (HR MAS) nuclear magnetic resonance (NMR) spectroscopy is increasingly being used to study metabolite levels in human breast cancer tissue, assessing, for instance, correlations with prognostic factors, survival outcome or therapeutic response. However, the impact of intratumoral heterogeneity on metabolite levels in breast tumor tissue has not been studied comprehensively. More specifically, when biopsy material is analyzed, it remains questionable whether one biopsy is representative of the entire tumor. Therefore, multi‐core sampling (n = 6) of tumor tissue from three patients with breast cancer, followed by lipid (0.9‐ and 1.3‐ppm signals) and metabolite quantification using HR MAS ¹H NMR, was performed, resulting in the quantification of 32 metabolites. The mean relative standard deviation across all metabolites for the six tumor cores sampled from each of the three tumors ranged from 0.48 to 0.74. This was considerably higher when compared with a morphologically more homogeneous tissue type, here represented by murine liver (0.16–0.20). Despite the seemingly high variability observed within the tumor tissue, a random forest classifier trained on the original sample set (training set) was, with one exception, able to correctly predict the tumor identity of an independent series of cores (test set) that were additionally sampled from the same three tumors and analyzed blindly. Moreover, significant differences between the tumors were identified using one‐way analysis of variance (ANOVA), indicating that the intertumoral differences for many metabolites were larger than the intratumoral differences for these three tumors. That intertumoral differences, on average, were larger than intratumoral differences was further supported by the analysis of duplicate tissue cores from 15 additional breast tumors. In summary, despite the observed intratumoral variability, the results of the present study suggest that the analysis of one, or a few, replicates per tumor may be acceptable, and supports the feasibility of performing reliable analyses of patient tissue.     

High‐grade neuroepithelial tumor with BCOR exon 15 internal tandem duplication—a comprehensive clinical,radiographic, pathologic,and genomic analysis

High‐grade neuroepithelial tumor with BCOR exon 15 internal tandem duplication (HGNET BCOR ex15 ITD) is a recently proposed tumor entity of the central nervous system (CNS) with a distinct methylation profile and characteristic genetic alteration. The complete spectrum of histologic features, accompanying genetic alterations, clinical outcomes, and optimal treatment for this new tumor entity are largely unknown. Here, we performed a comprehensive assessment of 10 new cases of HGNET BCOR ex15 ITD. The tumors mostly occurred in young children and were located in the cerebral or cerebellar hemispheres. On imaging all tumors were large, well‐circumscribed, heterogeneous masses with variable enhancement and reduced diffusion. They were histologically characterized by predominantly solid growth, glioma‐like fibrillarity, perivascular pseudorosettes, and palisading necrosis, but absence of microvascular proliferation. They demonstrated sparse to absent GFAP expression, no synaptophysin expression, variable OLIG2 and NeuN positivity, and diffuse strong BCOR nuclear positivity. While BCOR exon 15 internal tandem duplication was the solitary pathogenic alteration identified in six cases, four cases contained additional alterations including CDKN2A/B homozygous deletion, TERT amplification or promoter hotspot mutation, and damaging mutations in TP53, BCORL1, EP300, SMARCA2 and STAG2. While the limited clinical follow‐up in prior reports had indicated a uniformly dismal prognosis for this tumor entity, this cohort includes multiple long‐term survivors. Our study further supports inclusion of HGNET BCOR ex15 ITD as a distinct CNS tumor entity and expands the known clinicopathologic, radiographic, and genetic features.     

In vivo 1H MRS of WSU‐DLCL2 human non‐Hodgkin's lymphoma xenografts: response to rituximab and rituximab plus CHOP

In order to identify early ¹H MRS metabolic markers of response to rituximab immunotherapy and to rituximab plus CHOP (cyclophosphamide, hydroxydoxorubicin, vincristine, and prednisone) combination therapy, we performed an in vivo MRS investigation of a non‐Hodgkin's lymphoma (NHL) xenograft model. Human WSU‐DLCL2 NHL cells were subcutaneously implanted into flanks of female severe combined immunodeficient mice. When tumor volumes reached ～600 mm³, rituximab was administered for three weekly cycles at a dose of 25 mg/kg per cycle with or without CHOP. Before and after treatment, tumor lactate (Lac) and total choline (tCho) were detected using the selective multiple quantum coherence sequence and the stimulated echo acquisition mode sequence, respectively. Rituximab produced a small tumor growth delay (～5 days), whereas treatment with rituximab plus CHOP (RCHOP) led to ～20% tumor regression after three cycles of therapy. After one cycle of rituximab, the tCho/H₂O ratio had decreased significantly (5%, P = 0.003), whereas the Lac/H₂O ratio had not changed (P = 0.58). Both Lac/H₂O and tCho/H₂O had decreased after one cycle of RCHOP treatment (26%, P = 0.001; 10%, P = 0.016, respectively). After two cycles of RCHOP, Ki67 assay of histological tumor specimens indicated ～40% decrease in proliferation (P < 0.001) in the RCHOP‐treated tumors; no change was detected after treatment with rituximab alone. This study suggests that decreases in tCho/H₂O are more sensitive indices of response to rituximab, whereas decreases in Lac/H₂O are more sensitive to response to CHOP combination therapy. Copyright © 2008 John Wiley & Sons, Ltd.     

Utility of P16 expression and Ki‐67 proliferation index in ASCUS and ASC‐H pap tests

Current cervical screening uses a combination of cytology and high‐risk human papillomavirus (HR‐HPV) analysis in cases of atypical squamous cells of undetermined significance (ASCUS) and atypical squamous cells cannot exclude high‐grade intraepithelial lesion (ASC‐H). These diagnoses are subject to interobserver variability and HR‐HPV analysis can be limited by sampling inadequacy. This study correlates immunoexpression of P16 and Ki‐67 in residual cervicovaginal material against cytology category and HR‐HPV status. Eighteen pap tests were selected: 8 ASCUS, 4 ASC‐H, and 6 controls (2 LSIL and 4 HSIL). Digene Hybrid Capture II test was used to detect HR‐HPV. The cytospins were stained for P16/Ki‐67. Pap tests, P16, Ki‐67, HR‐HPV result and available biopsies were correlated. P16 expression correlated with HR‐HPV status in 15/17 cases. Discordant cases (1 ASCUS and 1 ASC‐H) were +P16/–HR‐HPV. Ki‐67 correlated with HR‐HPV in 8/15 cases. Discordant cases were +HR‐HPV/– Ki‐67 (HSIL, LSIL, and ASC‐H one each), and –HR‐HPV/+Ki‐67 (3 ASCUS, 1 LSIL, 1 ASC‐H). Two cases were + P16/+ Ki‐67/– HR‐HPV. None were ‐ P16/– Ki‐67/+ HR‐HPV. Histologic follow‐up in 13 cases varied from benign to CIN III. Two cases of +P16/ – Ki‐67/– HR‐HPV had benign cervical biopcies. Although a small sample size, our findings show a utility for adjunct P16/ Ki‐67 in addition to HR‐HPV testing in cases of squamous atypia when HR‐HPVs are non‐detected due to low DNA copies, or missed lesions in cervical biopsies. Diagn. Cytopathol. 2014;42:576–581. © 2013 Wiley Periodicals, Inc.     

Genomic analysis of low‐grade serous ovarian carcinoma to identify key drivers and therapeutic vulnerabilities

Low‐grade serous ovarian carcinoma (LGSOC) is associated with a poor response to existing chemotherapy, highlighting the need to perform comprehensive genomic analysis and identify new therapeutic vulnerabilities. The data presented here represent the largest genetic study of LGSOCs to date (n = 71), analysing 127 candidate genes derived from whole exome sequencing cohorts to generate mutation and copy‐number variation data. Additionally, immunohistochemistry was performed on our LGSOC cohort assessing oestrogen receptor, progesterone receptor, TP53, and CDKN2A status. Targeted sequencing identified 47% of cases with mutations in key RAS/RAF pathway genes (KRAS, BRAF, and NRAS), as well as mutations in putative novel driver genes including USP9X (27%), MACF1 (11%), ARID1A (9%), NF2 (4%), DOT1L (6%), and ASH1L (4%). Immunohistochemistry evaluation revealed frequent oestrogen/progesterone receptor positivity (85%), along with CDKN2A protein loss (10%) and CDKN2A protein overexpression (6%), which were linked to shorter disease outcomes. Indeed, 90% of LGSOC samples harboured at least one potentially actionable alteration, which in 19/71 (27%) cases were predictive of clinical benefit from a standard treatment, either in another cancer's indication or in LGSOC specifically. In addition, we validated ubiquitin‐specific protease 9X (USP9X), which is a chromosome X‐linked substrate‐specific deubiquitinase and tumour suppressor, as a relevant therapeutic target for LGSOC. Our comprehensive genomic study highlighted that there is an addiction to a limited number of unique ‘driver’ aberrations that could be translated into improved therapeutic paths. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Comparative genomic hybridization analysis of hepatoblastoma reveals high frequency of X-chromosome gains and similarities between epithelial and stromal components

Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm.     

Lactate and glycine—potential MR biomarkers of prognosis in estrogen receptor‐positive breast cancers

Breast cancer is a heterogeneous disease with a variable prognosis. Clinical factors provide some information about the prognosis of patients with breast cancer; however, there is a need for additional information to stratify patients for improved and more individualized treatment. The aim of this study was to examine the relationship between the metabolite profiles of breast cancer tissue and 5‐year survival. Biopsies from breast cancer patients (n = 98) were excised during surgery and analyzed by high‐resolution magic angle spinning MRS. The data were analyzed by multivariate principal component analysis and partial least‐squares discriminant analysis, and the findings of important metabolites were confirmed by spectral integration of the metabolite peaks. Predictions of 5‐year survival using metabolite profiles were compared with predictions using clinical parameters. Based on the metabolite profiles, patients with estrogen receptor (ER)‐positive breast cancer (n = 71) were separated into two groups with significantly different survival rates (p = 0.024). Higher levels of glycine and lactate were found to be associated with lower survival rates by both multivariate analyses and spectral integration, and are suggested as biomarkers for breast cancer prognosis. Similar metabolic differences were not observed for ER‐negative patients, where survivors could not be separated from nonsurvivors. Predictions of 5‐year survival of ER‐positive patients using metabolite profiles gave better and more robust results than those using traditional clinical parameters. The results imply that the metabolic state of a tumor may provide additional information concerning breast cancer prognosis. Further studies should be conducted in order to evaluate the role of MR metabolomics as an additional clinical tool for determining the prognosis of patients with breast cancer. Copyright © 2012 John Wiley & Sons, Ltd.     

The characteristic expression of B7‐H3 and B7‐H4 in liver biopsies from patients with HBV‐related acute‐on‐chronic liver failure

Hepatitis B virus (HBV) is a major public health problem, and HBV‐related acute‐on‐chronic liver failure (HBV‐ACLF) has an extremely poor prognosis due to a lack of effective treatments. B7‐H3 and B7‐H4 are two novel members of the B7 superfamily that are actively involved in regulating the pathogenesis of infectious diseases. However, the intrahepatic expression of both members in HBV‐ACLF patients has yet to be described. In this study, we analyzed the expression of B7‐H3 and B7‐H4 in HBV‐ACLF biopsies by immunohistochemistry. Our results showed that both members were observed in all HBV‐ACLF samples, and their expression was chiefly observed on infiltrating inflammatory cells and the damaged bile ducts. Immunofluorescence double staining showed that B7‐H4 was expressed chiefly on CD3⁺ T cells, CD68⁺ macrophages, CK‐18⁺ bile ducts, and CD31⁺ endothelial cells, while B7‐H3 was found on all cell types detected. The expression of the programmed death (PD)‐1 ligands, PD‐L1 and PD‐L2, was also detected in these liver tissues and they were found to be co‐expressed with B7‐H3 and B7‐H4. These results suggest that the B7‐family signaling is most likely to affect the pathogenesis of this disease, and a clear understanding of their functional roles may further elucidate the disease process.     

A comparative study of short‐ and long‐TE 1H MRS at 3 T for in vivo detection of 2‐hydroxyglutarate in brain tumors

2‐Hydroxyglutarate (2HG) is produced in gliomas with mutations of isocitrate dehydrogenase (IDH) 1 and 2. The ¹H resonances of the J‐coupled spins of 2HG are extensively overlapped with signals from other metabolites. Here, we report a comparative study at 3 T of the utility of the point‐resolved spectroscopy sequence with a standard short TE (35 ms) and a long TE (97 ms), which had been theoretically designed for the detection of the 2HG 2.25‐ppm resonance. The performance of the methods is evaluated using data from phantoms, seven healthy volunteers and 22 subjects with IDH‐mutated gliomas. The results indicate that TE = 97 ms provides higher detectability of 2HG than TE = 35 ms, and that this improved capability is gained when data are analyzed with basis spectra that include the effects of the volume localizing radiofrequency and gradient pulses. Copyright © 2013 John Wiley & Sons, Ltd.