Acute oesophageal necrosis (black oesophagus).

A 54-year-old man was admitted to hospital after being found unconscious in his home. He had a history of alcoholism, multiple drug addictions, and type I diabetes mellitus. At admission, he had hyperglycaemia (550 mg/dL) with glucosuria and ketone bodies in the urine, along with septic shock refractory to bilateral alveolar infiltrates and severe respiratory failure. The patient died 24 hours post admission due to multiple organ failure, with diabetic ketoacidosis decompensated by possible respiratory infection in a patient with polytoxicomania. The autopsy confirmed the presence of acute bilateral bronchopneumonia, chronic pancreatitis, severe hepatic steatosis, and generalized congestive changes. At the oesophagus, acute oesophageal necrosis was evident.

Necrosis esofágica aguda (esófago negro) / Acute oesophageal necrosis (black oesophagus)

No disponible

Next-generation prostate cancer biobanking: toward a processing protocol amenable for the International Cancer Genome Consortium.

Next-generation DNA and RNA sequencing requires intact nucleic acids from high-quality human tissue samples to better elucidate the molecular basis of cancer. We have developed a prostate biobanking protocol to acquire suitable samples for sequencing without compromising the accuracy of clinical diagnosis. To assess the clinical implications of implementing this protocol, we evaluated 105 consecutive radical prostatectomy specimens from November 2008 to February 2009. Alternating levels of prostate samples were submitted to Surgical Pathology as formalin-fixed, paraffin-embedded blocks and to the institutional biobank as frozen blocks. Differences in reported pathologic characteristics between clinical and procured specimens were compared. Clinical staging and grading were not affected by the biobank protocol. Tumor foci on frozen hematoxylin and eosin slides were identified and high-density tumor foci were scored and processed for DNA and RNA extractions for sequencing. Both DNA and RNA were extracted from 22 cases of 44 with high-density tumor foci. Eighty-two percent (18/22) of the samples passed rigorous quality control steps for DNA and RNA sequencing. To date, DNA extracted from 7 cases has undergone whole-genome sequencing, and RNA from 18 cases has been RNA sequenced. This protocol provides prostate tissue for high-throughput biomedical research and confirms the feasibility of actively integrating prostate cancer into The Cancer Genome Atlas Program, a member of the International Cancer Genome Consortium.

The genomic complexity of primary human prostate cancer.

Prostate cancer is the second most common cause of male cancer deaths in the United States. However, the full range of prostate cancer genomic alterations is incompletely characterized. Here we present the complete sequence of seven primary human prostate cancers and their paired normal counterparts. Several tumours contained complex chains of balanced (that is, 'copy-neutral') rearrangements that occurred within or adjacent to known cancer genes. Rearrangement breakpoints were enriched near open chromatin, androgen receptor and ERG DNA binding sites in the setting of the ETS gene fusion TMPRSS2-ERG, but inversely correlated with these regions in tumours lacking ETS fusions. This observation suggests a link between chromatin or transcriptional regulation and the genesis of genomic aberrations. Three tumours contained rearrangements that disrupted CADM2, and four harboured events disrupting either PTEN (unbalanced events), a prostate tumour suppressor, or MAGI2 (balanced events), a PTEN interacting protein not previously implicated in prostate tumorigenesis. Thus, genomic rearrangements may arise from transcriptional or chromatin aberrancies and engage prostate tumorigenic mechanisms.

TMPRSS2-ERG gene fusion prevalence and class are significantly different in prostate cancer of Caucasian, African-American and Japanese patients.

BACKGROUND: Prostate cancer (PCa) exhibits significant differences in prevalence and mortality among different ethnic groups. The underlying genetics is not well understood. TMPRSS2-ERG fusion is a common recurrent chromosomal aberration in PCa and is however not studied among different ethnic groups. We examined the prevalence and class of TMPRSS2-ERG gene fusion in PCa from Caucasian, African-American, and Japanese patients. MATERIALS AND METHODS: A tissue microarray of PCa from 42 Caucasians, 64 African-Americans, and 44 Japanese patients who underwent radical prostatectomies (RP) was studied for TMPRSS2-ERG fusion using a multicolor interphase fluorescence in situ hybridization assay for ERG gene break-apart. RESULTS: TMPRSS2-ERG gene fusion was present in 50% (21/42) of Caucasians, 31.3% (20/64) of African-Americans, and 15.9% (7/44) of Japanese (P=0.003). The gene fusion through translocation, deletion, or both occurred in 61.9% (13/21), 38.1% (8/21), and 0% (0/21) in Caucasians, 20% (4/20), 60% (12/20), and 20% (4/20) in African-Americans, and 71.4% (5/7), 28.6% (2/7), and 0% (0/7) in Japanese patients (P=0.02). A multivariate analysis demonstrated that TMPRSS2-ERG gene fusion correlated with the ethnicity (P=0.03), marginally correlated with the pathologic stage (P=0.06), but not other clinicopathologic parameters, including age, preoperative PSA levels, and Gleason score. CONCLUSIONS: The prevalence and class of TMPRSS2-ERG are significantly different in PCa of Caucasian, African-American, and Japanese patients. Future studies of the molecular pathways implicated in TMPRSS2-ERG gene fusion may shed light on the disparity in prevalence and mortality of PCa among different ethnic groups and help design better prevention and treatment strategies.

Discovery of non-ETS gene fusions in human prostate cancer using next-generation RNA sequencing.

Half of prostate cancers harbor gene fusions between TMPRSS2 and members of the ETS transcription factor family. To date, little is known about the presence of non-ETS fusion events in prostate cancer. We used next-generation transcriptome sequencing (RNA-seq) in order to explore the whole transcriptome of 25 human prostate cancer samples for the presence of chimeric fusion transcripts. We generated more than 1 billion sequence reads and used a novel computational approach (FusionSeq) in order to identify novel gene fusion candidates with high confidence. In total, we discovered and characterized seven new cancer-specific gene fusions, two involving the ETS genes ETV1 and ERG, and four involving non-ETS genes such as CDKN1A (p21), CD9, and IKBKB (IKK-beta), genes known to exhibit key biological roles in cellular homeostasis or assumed to be critical in tumorigenesis of other tumor entities, as well as the oncogene PIGU and the tumor suppressor gene RSRC2. The novel gene fusions are found to be of low frequency, but, interestingly, the non-ETS fusions were all present in prostate cancer harboring the TMPRSS2-ERG gene fusion. Future work will focus on determining if the ETS rearrangements in prostate cancer are associated or directly predispose to a rearrangement-prone phenotype.

Antibody-based detection of ERG rearrangement-positive prostate cancer.

TMPRSS2-ERG gene fusions occur in 50% of prostate cancers and result in the overexpression of a chimeric fusion transcript that encodes a truncated ERG product. Previous attempts to detect truncated ERG products have been hindered by a lack of specific antibodies. Here, we characterize a rabbit anti-ERG monoclonal antibody (clone EPR 3864; Epitomics, Burlingame, CA) using immunoblot analysis on prostate cancer cell lines, synthetic TMPRSS2-ERG constructs, chromatin immunoprecipitation, and immunofluorescence. We correlated ERG protein expression with the presence of ERG gene rearrangements in prostate cancer tissues using a combined immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) analysis. We independently evaluated two patient cohorts and observed ERG expression confined to prostate cancer cells and high-grade prostatic intraepithelial neoplasia associated with ERG-positive cancer, as well as vessels and lymphocytes (where ERG has a known biologic role). Image analysis of 131 cases demonstrated nearly 100% sensitivity for detecting ERG rearrangement prostate cancer, with only 2 (1.5%) of 131 cases demonstrating strong ERG protein expression without any known ERG gene fusion. The combined pathology evaluation of 207 patient tumors for ERG protein expression had 95.7% sensitivity and 96.5% specificity for determining ERG rearrangement prostate cancer. In conclusion, this study qualifies a specific anti-ERG antibody and demonstrates exquisite association between ERG gene rearrangement and truncated ERG protein product expression. Given the ease of performing IHC versus FISH, ERG protein expression may be useful for molecularly subtyping prostate cancer based on ERG rearrangement status and suggests clinical utility in prostate needle biopsy evaluation.

Rearrangements of the RAF kinase pathway in prostate cancer, gastric cancer and melanoma.

Although recurrent gene fusions involving erythroblastosis virus E26 transformation-specific (ETS) family transcription factors are common in prostate cancer, their products are considered 'undruggable' by conventional approaches. Recently, rare targetable gene fusions involving the anaplastic lymphoma receptor tyrosine kinase (ALK) gene, have been identified in 1-5% of lung cancers, suggesting that similar rare gene fusions may occur in other common epithelial cancers, including prostate cancer. Here we used paired-end transcriptome sequencing to screen ETS rearrangement-negative prostate cancers for targetable gene fusions and identified the SLC45A3-BRAF (solute carrier family 45, member 3-v-raf murine sarcoma viral oncogene homolog B1) and ESRP1-RAF1 (epithelial splicing regulatory protein-1-v-raf-1 murine leukemia viral oncogene homolog-1) gene fusions. Expression of SLC45A3-BRAF or ESRP1-RAF1 in prostate cells induced a neoplastic phenotype that was sensitive to RAF and mitogen-activated protein kinase kinase (MAP2K1) inhibitors. Screening a large cohort of patients, we found that, although rare, recurrent rearrangements in the RAF pathway tend to occur in advanced prostate cancers, gastric cancers and melanoma. Taken together, our results emphasize the key role of RAF family gene rearrangements in cancer, suggest that RAF and MEK inhibitors may be useful in a subset of gene fusion-harboring solid tumors and demonstrate that sequencing of tumor transcriptomes and genomes may lead to the identification of rare targetable fusions across cancer types.

Prevalence of TMPRSS2-ERG and SLC45A3-ERG gene fusions in a large prostatectomy cohort.

The majority of prostate cancers harbor recurrent gene fusions between the hormone-regulated TMPRSS2 and members of the ETS family of transcription factors, most commonly ERG. Prostate cancer with ERG rearrangements represent a distinct sub-class of tumor based on studies reporting associations with histomorphologic features, characteristic somatic copy number alterations, and gene expression signatures. This study describes the frequency of ERG rearrangement prostate cancer and three 5 prime (5') gene fusion partners (ie, TMPRSS2, SLC45A3, and NDRG1) in a large prostatectomy cohort. ERG gene rearrangements and mechanism of rearrangement, as well as rearrangements of TMPRSS2, SLC45A3, and NDRG1, were assessed using fluorescence in situ hybridization (FISH) on prostate cancer samples from 614 patients treated using radical prostatectomy. ERG rearrangement occurred in 53% of the 540 assessable cases. TMPRSS2 and SLC45A3 were the only 5' partner in 78% and 6% of these ERG rearranged cases, respectively. Interestingly, 11% of the ERG rearranged cases showed concurrent TMPRSS2 and SLC45A3 rearrangements. TMPRSS2 or SLC45A3 rearrangements could not be identified for 5% of the ERG rearranged cases. From these remaining cases we identified one case with NDRG1 rearrangement. We did not observe any associations with pathologic parameters or clinical outcome. This is the first study to describe the frequency of SLC45A3-ERG fusions in a large clinical cohort. Most studies have assumed that all ERG rearranged prostate cancers harbor TMPRSS2-ERG fusions. This is also the first study to report concurrent TMPRSS2 and SLC45A3 rearrangements in the same tumor focus, suggesting additional complexity that had not been previously appreciated. This study has important clinical implications for the development of diagnostic assays to detect ETS rearranged prostate cancer. Incorporation of these less common ERG rearranged prostate cancer fusion assays could further increase the sensitivity of the current PCR-based approaches.

FGFR3 mutations in prostate cancer: association with low-grade tumors.

Prostate cancer is the second cause of cancer-related death in men of the Western World. The role of FGFR3 and its abnormalities in prostate cancer are not known. FGFR3 mutations have been reported in some human tumors. Few studies have analyzed the mutations of FGFR3 in prostate tumors, and no mutations have been previously reported. Prevalence of FGFR3 somatic mutations was investigated in a series of prostate tumors. The presence of other tumors in these patients, including urothelial, skin, colon, and lung neoplasms, was recorded. Mutational analysis of exons 7, 10, and 15 of FGFR3 revealed 9 mutations in the 112 prostate tumors studied (8%). Most of them consisted of the missense change S249C. The prevalence of mutations in tumors with combined Gleason score=6 is 18% (8/45) compared to 3% (1/36) for tumors with grade=7, and 0% (0/31) for those with grade >or=8 and metastases (P=0.007). The frequency of FGFR3 mutations in autopsy and biopsy samples was 6 and 9%, respectively. The prevalence of FGFR3 mutations in prostate tumors from patients with only prostate cancer was 2% compared to 23% in prostate tumors from patients with other associated neoplasms (P=0.001). This is the first report of molecular changes of FGFR3 in prostate cancer. This gene does not seem to be central to the pathogenesis of prostate cancer, but it is significantly associated with a subgroup of low-grade prostate tumors, and with the finding of other tumors, mainly arising in bladder and skin.

KLF6 and TP53 mutations are a rare event in prostate cancer: distinguishing between Taq polymerase artifacts and true mutations.

Krüppel-like factor 6 (KLF6) has been reported to act as a tumor suppressor gene involved in the regulation of the cell cycle by activating p21 in a p53-independent manner. Many studies suggest that KLF6 is inactivated by allelic loss and somatic mutation. However, there is a high variability in the reported frequency of mutations (from 1 to 55%). TP53 also regulates the cell cycle through the activation of p21. In prostate cancer, the reported frequency of TP53 mutations ranges from 3 to 42%. In all these reports, there is a considerable degree of methodological heterogeneity. Our aim was to determine the frequency of KLF6 and TP53 mutations in a well-defined group of prostate tumors with different stages and Gleason grades. The four exons of KLF6 and exons 4-9 of TP53 were studied in 103 cases, including 90 formalin-fixed, paraffin-embedded (FFPE) and 13 frozen samples. All tumors were analyzed through PCR and direct sequencing. All changes found were confirmed by a second independent PCR and sequencing reaction. For KLF6, mutation (E227G) was only detected in one tumor (1%) and for TP53, three different mutations (L130H, H214R, and Y234C) were detected in five tumors (5%). This low mutation index is in keeping with recent papers on the subject. Our study strongly supports the notion that KLF6 and TP53 mutations are not frequent events in prostate cancer. When using FFPE tissues, it is mandatory to perform at least two independent rounds of PCR and sequencing to confirm mutations and exclude Taq polymerase-induced artifacts.

Fatal liver failure: molecular evidence for chronic active Epstein-Barr virus infection.

Epstein-Barr virus (EBV) infection is a benign disease, which may occasionally be fatal, particularly in children and immunocompromised patients. Epstein-Barr virus infection is rare in elderly subjects and seems to have a self-limited course. A case of fatal liver failure due to chronic active EBV infection in a 75-year-old man is described. The etiology was established postmortem by cellular expression of EBV-DNA in liver and lymphatic tissue. This patient meets the diagnostic criteria of a case definition for a highly probable "severe chronic active EBV syndrome." Either suspected or unsuspected, the long-term prognosis of this syndrome is poor and its mortality high.