Adriana Krizova

Accurate Molecular Classification of Kidney Cancer Subtypes Using MicroRNA Signature

BACKGROUND Renal cell carcinoma (RCC) encompasses different histologic subtypes. Distinguishing between the subtypes is usually made by morphologic assessment, which is not always accurate. OBJECTIVE Our aim was to identify microRNA (miRNA) signatures that can distinguish the different RCC subtypes accurately. DESIGN, SETTING, AND PARTICIPANTS A total of 94 different subtype cases were analysed. miRNA microarray analysis was performed on fresh frozen tissues of three common RCC subtypes (clear cell, chromophobe, and papillary) and on oncocytoma. Results were validated on the original as well as on an independent set of tumours, using quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis with miRNA-specific primers. MEASUREMENTS Microarray data were analysed by standard approaches. Relative expression for qRT-PCR was determined using the ΔΔC(T) method, and expression values were normalised to small nucleolar RNA, C/D box 44 (SNORD44, formerly RNU44). Experiments were done in triplicate, and an average was calculated. Fold change was expressed as a log(2) value. The top-scoring pairs classifier identified operational decision rules for distinguishing between different RCC subtypes and was robust under cross-validation. RESULTS AND LIMITATIONS We developed a classification system that can distinguish the different RCC subtypes using unique miRNA signatures in a maximum of four steps. The system has a sensitivity of 97% in distinguishing normal from RCC, 100% for clear cell RCC (ccRCC) subtype, 97% for papillary RCC (pRCC) subtype, and 100% accuracy in distinguishing oncocytoma from chromophobe RCC (chRCC) subtype. This system was cross-validated and showed an accuracy of about 90%. The oncogenesis of ccRCC is more closely related to pRCC, whereas chRCC is comparable with oncocytoma. We also developed a binary classification system that can distinguish between two individual subtypes. CONCLUSIONS MiRNA expression patterns can distinguish between RCC subtypes.

Neuroimaging Week: A Novel, Engaging, and Effective Curriculum for Teaching Neuroimaging to Junior Psychiatric Residents

ObjectiveNeuroimaging techniques are increasingly important in psychiatric research and clinical practice, but few postgraduate psychiatry programs offer formal training in neuroimaging. To address this need, the authors developed a course to prepare psychiatric residents to use neuroimaging techniques effectively in independent practice.MethodsThe authors present the format and curriculum of a highly interactive, 5- day intensive neuroimaging course, taught by psychiatry, neurology, radiology, nuclear medicine, and sleep medicine staff, covering psychiatrically oriented neuroanatomy; neuroimaging techniques and principles; clinical skills, including interpretation of computed tomography and MRI in neuro- psychiatric cases; and formal approaches to critiquing neuroimaging research and applying its findings to clinical practice. Detailed questionnaires assessed the subjective and objective impact of the course on residents’ knowledge of, and attitudes toward, neuroimaging in psychiatry before and after the course.ResultsTwenty-five first- year residents completed the questionnaires. Participants were enthusiastic about the content and interested in improving their skills in interpreting clinical neuroimaging studies. By the end of the course, residents also reported large gains in subjective comfort level with neuroimaging literature appraisal and functional neuroanatomy and believed that the course was effective in meeting their own specific learning objectives. Objective measures showed significant gains in most areas of the curriculum.ConclusionThis short, intensive course effectively teaches clinically oriented neuroimaging principles to psychiatric residents and can be readily adapted to other postgraduate programs or continuing medical education.

miR-10b is a prognostic marker in clear cell renal cell carcinoma

Aims Clear cell renal cell carcinoma (ccRCC) is the most common adult kidney cancer. It is an aggressive tumour with unpredictable outcome. The currently used clinical parameters are not always accurate for predicting disease behaviour. miR-10b is dysregulated in different malignancies including RCC. Methods We assessed the clinical utility of miR-10b as a prognostic marker in 250 patients with primary ccRCC. We examined the correlation between miR-10b and clinicopathological parameters. We compared miR-10b expression among different RCC subtypes and normal kidney tissue. Results We observed a stepwise decrease of miR-10b expression from normal kidney to primary ccRCC and a further decrease from primary to metastatic RCC. miR-10b expression was significantly lower in stages III/IV compared with stages I/II (p=0.038). Using a binary cut-off, miR-10b-positive patients had significantly longer disease-free survival (HR=0.47, CI 0.28 to 0.79, p=0.004). In the subgroup of patients with tumour size >4 cm, higher miR-10b expression was associated with significant longer disease-free and overall survival (p=0.001 and p=0.036, respectively). miR-10b was significantly downregulated in ccRCC compared with normal kidney (p<0.0001), and oncocytoma (p=0.031). It was also downregulated in chromophobe RCC. In addition, we identified a number of miR-10b-predicted targets and pathways that are involved in tumourigenesis. Conclusions Our data point to miR-10b as a promising prognostic marker in ccRCC with potential therapeutic applications.

Fatal laryngeal angioedema: a case report and a workup of angioedema in a forensic setting

Angioedema is an episodic swelling of the deep dermis, subcutis, and/or submucosal tissue due to an increase in local vascular permeability. Swelling may involve skin, respiratory, and gastrointestinal tracts. The most commonly involved areas are the periorbital region and the lips. Here we report a case of a fatal laryngeal obstruction due to angioedema likely caused by an angiotensin-converting-enzyme inhibitor. The decedent, a 58-year-old man, was witnessed developing sudden facial swelling and acute respiratory difficulties quickly followed by unresponsiveness. His past medical history suggested that this was his second episode of angioedema without urticaria. Postmortem examination revealed a complete laryngeal obstruction in the absence of infection, neoplasm, or autoimmune disease. Postmortem computed tomography of the head and neck showed a complete obstruction of the upper airway. Based on the current understanding of the pathophysiology of different types of angioedema, we will suggest a workup of angioedema without urticaria in the forensic setting and offer readers resources they can use in their practice.

Integrated Phenotypic/Genotypic Analysis of Papillary Renal Cell Carcinoma Subtypes: Identification of Prognostic Markers, Cancer-related Pathways, and Implications for Therapy

BACKGROUND Two histologic subtypes are recognized for papillary renal cell carcinoma (PRCC). Studies have shown that the subtypes differ in characteristic genetic alterations and clinical behavior. Clinically, the subtypes are managed similarly. OBJECTIVES To analyze the biological differences between the two PRCC histological subtypes, in order to further guide their clinical management. DESIGN, SETTING, AND PARTICIPANTS PRCC cohort consisting of 317 patients from the Cancer Genome Atlas database and our institution. Patients were stratified according to histologic criteria as type 1, type 2, or not otherwise specified (NOS). Gene and miRNA expression data for the cohort were examined via unsupervised and supervised clustering. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Significant molecular signatures for each subtype were used to unravel the implicated molecular pathways via bioinformatics analysis. Survival was compared between the subtypes. Newly discovered biomarkers were used to further stratify survival of patients in the NOS category. RESULTS AND LIMITATIONS Tumor genotyping revealed two distinct PRCC subtypes. The top molecular pathways enriched in PRCC1 were WNT, Hedgehog, and Notch signaling (p=0.001-0.01); highlighting an embryonic developmental theme to the pathogenesis of this subtype. PRCC2 showed enrichment in the mTOR, VEGF (p=7.49E-09) and HIF (p=7.63E-05) signaling pathways. Overall survival and disease-free survival significantly differed between the types. ABCC2 expression was identified as a significant prognostic biomarker for the NOS group in univariate (log rank p<0.0001; hazard ratio [HR] >11.63) and multivariate analysis (p=0.003; HR >2.12). ABCC2 expression and its effect on survival should be further validated at the protein level. CONCLUSIONS The classical PRCC types 1 and 2 have two distinct genotypes. We unraveled pathways that indicate that the two types could potentially respond differently to current therapies. We also identified biomarkers that stratify tumors within the PRCC NOS category into prognostic subgroups. Our findings highlight the need for molecular markers to accurately subtype PRCC and guide clinical management. PATIENT SUMMARY The two types of papillary renal cancer are treated similarly. We show that the two types have a different genetic makeup, and hence they should be considered two different tumors. There is a different biology underlying each tumor type that can potentially affect the way they respond to treatment. We uncovered genes that can be tested for to guide therapy in some problematic cases for which it hard to define the tumor type.

Clear cell papillary renal cell carcinoma as part of histologically discordant multifocal renal cell carcinoma: A case report and review of literature.

BACKGROUND Multifocal renal cell carcinoma of different histological subtypes within a single kidney is rare. We report a recently classified clear cell (tubulo) papillary renal cell carcinoma as part of an unusual case of multifocal renal cell carcinoma of discordant histological subtypes. RESULTS A 57 year-old-man was found to have multiple renal tumors and cysts on imaging and underwent a laparoscopic left radical nephrectomy. Pathological review showed multifocal renal cell carcinoma (clear cell (tubulo) papillary, clear cell and papillary renal cell carcinomas and papillary adenomas). Morphology of clear cell papillary renal cell carcinoma was supported by immunohistochemical profile (CK7+, HMWK+, CAIX+, AMACR-, CD10-, TFE3-). CONCLUSIONS This is the first report of clear cell papillary renal cell carcinoma as part of multifocal renal cell carcinoma of different histological subtypes. Related lineage of clear cell renal cell carcinoma and papillary renal cell carcinoma is supported by the highest prevalence of their combination within multifocal renal cell carcinoma of different histological subtypes along with their molecular interconnection. Clear cell papillary renal cell carcinoma may be uniquely placed between clear cell and papillary renal cell carcinomas since it shows morphological features intermediate between clear cell and papillary renal cell carcinoma along with overlapping but unique immunohistochemical profile. Clear cell papillary renal cell carcinoma may be molecularly related to clear cell and papillary renal cell carcinomas since the tumors overexpress markers of HIF pathway activation with normal/elevated VHL mRNA expression and some tumors show losses of chromosome 3. Due to the overlapping morphology, it is possible that cases of clear cell papillary renal cell carcinoma may have been misclassified as papillary or clear cell renal cell carcinoma in the literature, incorrectly increasing their reported prevalence. Identification of multifocal RCCs may be related to the extent of pathological sampling.

A miRNA-based classification of renal cell carcinoma subtypes by PCR and in situ hybridization

Renal cell carcinoma (RCC) constitutes an array of morphologically and genetically distinct tumors the most prevalent of which are clear cell, papillary, and chromophobe RCC. Accurate distinction between the typically benign-behaving renal oncocytoma and RCC subtypes is a frequent challenge for pathologists. This is critical for clinical decision making. Subtypes also have different survival outcomes and responses to therapy. We extracted RNA from ninety formalin-fixed paraffin-embedded (FFPE) tissues (27 clear cell, 29 papillary, 19 chromophobe, 4 unclassified RCC and 11 oncocytomas). We quantified the expression of six miRNAs (miR-221, miR-222, miR-126, miR-182, miR-200b and miR-200c) by qRT-PCR, and by in situ hybridization in an independent set of tumors. We developed a two-step classifier. In the first step, it uses expression of either miR-221 or miR-222 to distinguish the clear cell and papillary subtypes from chromophobe RCC and oncocytoma (miR-221 AUC: 0.96, 95% CI: 0.9132–1.014, p < 0.0001 and miR-222 AUC: 0.91, 95% CI: 0.8478–0.9772, p < 0.0001). In the second step, it uses miR-126 to discriminate clear cell from papillary RCC (AUC: 1, p < 0.0001) and miR-200b to discriminate chromophobe RCC from oncocytoma (AUC: 0.95, 95% CI: 0.8933–1.021, p < 0.0001). In situ hybridization showed a nuclear staining pattern. miR-126, miR-222 and miR-200b were significantly differentially expressed between the subtypes by in situ hybridization. miRNA expression could distinguish RCC subtypes and oncocytoma. miRNA expression assessed by either PCR or in situ hybridization can be a clinically useful diagnostic tool to complement morphologic renal tumor classification, improving diagnosis and patient management.

Intra-Abdominal Hemorrhage Complicating Electrothermal Arterial Injury During Pelvic Surgery: A Case Report

Iatrogenic vascular injury is a potentially serious complication of surgical procedures. Here we report a case of delayed fatal intra-abdominal hemorrhage because of electrocautery injury of a right external iliac artery. The decedent, a 31-year-old woman, died suddenly on postoperative day 1 after a laparoscopic staging operation for an ovarian tumor. Her past medical history included a recent diagnosis of a microinvasive carcinoma in the background of a mucinous cystic neoplasm of the right ovary. Postmortem examination revealed a young woman with evidence of emergency intervention, recent laparoscopic pelvic surgery, and pale hypostasis limited to the back surfaces of the body. The internal examination confirmed the postmortem computed tomography findings of a large amount of blood in the pelvic and abdominal cavities and evidence of recent surgical intervention. The soft tissues around the aorta and major pelvic vessels showed electrocautery change and marked perivascular hemorrhage preferentially surrounding the right external iliac artery. Histological examination of the vascular bundle showed an electrocautery injury of the arterial wall: transmural necrosis, acute inflammation, and hemorrhage. In this report, we offer an approach to a postmortem examination in postoperative deaths with emphasis on deaths due to iatrogenic vascular injuries and discuss the rationale for determining the manner of death.

Postmortem CT, gross and microscopic images of hemorrhage along the pulmonary artery sheath due to type A aortic dissection

Dissection of blood into the mediastinum and along the bronchovascular tree is a rare complication of a Stanford type A aortic dissection [1–10]. Extravasated blood from the ruptured aorta spreads along the common adventitia of the aorta and the pulmonary artery and can travel along adventitial planes of the pulmonary arteries into the lungs. Sueyoshi et al. suggested that the worst patient outcome is associated with double-barreled aortic dissection and category 3 hemorrhage (extension of blood into the lung alveoli) [5]. In this report we show the correlation between postmortem computed tomography (PMCT) and gross and microscopic findings of hemorrhage extending from a type A aortic dissection along the pulmonary artery adventitial planes into the lung interstitium and pulmonary alveoli.

Pleotrophic action of renal cell carcinoma: Dysregulated microRNAs on hypoxia-related signaling pathways.

428 Background: The von Hippel-Lindau (VHL) gene is lost in 70% of clear cell Renal Cell Carcinomas (ccRCC); however, additional mechanisms are proposed to regulate VHL expression, including suppression by microRNAs (miRNAs). miRNAs are a class of naturally occurring, small non-coding RNA molecules that downregulate gene expression of target mRNAs. We demonstrate that ccRCC-dysregulated miRNAs can target multiple members of the ccRCC-related signaling pathways. METHODS miR-17 and miR-224 mimics and inhibitors were transfected into ccRCC cell lines using siPORT (Ambion). PicTar and TargetScan were used for target prediction. Target expression and miRNA expression was analyzed by qRT-PCR (Ambion). Western blot antibodies were purchased from Millipore or Cell Signaling. Cell lines were purchased from ATCC. All methods followed the manufacturers protocol. RESULTS According to our preliminary results, the miRNAs that are dysregulated in ccRCC specimens are predicted to target multiple members of the hypoxia-related pathways. To confirm the in silico analysis, miR-17 and miR-224 were selected for experimental target validation, as they were among the most up-regulated miRNAs in ccRCC. We experimentally validated VHL and HIF1α as likely direct targets of miR-17 and miR-224. Luciferase reporter assay confirmed that miR-17 directly downregulates VHL. Moreover, VHL protein level decreased upon miR-17 and miR-224 transfection. We also established a negative correlation between the expression of miR-17 and two predicted targets VEGF-A, EGLN3 in RCC specimens, and miR-224 and its predicted targets SMAD4 and SMAD5. This suggests that downstream signaling pathways are also modulated by miR-17 and miR-224. These results confirm the most important findings of the bioinformatics analysis: miR-17 targets different molecules along the same signaling pathway and that multiple ccRCC-dysregulated miRNAs can synergistically suppress a single target, which functions in the pathogenesis. CONCLUSIONS Our results indicate that miRNAs possibly regulate hypoxia-related pathways at multiple points. This is of special interest as miRNAs may serve as potential therapeutic targets.