High level of Ets-related gene expression has high specificity for prostate cancer: a tissue microarray study of 11 483 cancers

Mesenchymal Neoplasms of the Liver

Mesenchymal neoplasms of the liver can be diagnostically challenging, particularly on core needle biopsies. Here, I discuss recent updates in neoplasms that are specific to the liver (mesenchymal hamartoma, undifferentiated embryonal sarcoma, calcifying nested stromal-epithelial tumor), vascular tumors of the liver (anastomosing hemangioma, hepatic small vessel neoplasm, epithelioid hemangioendothelioma, angiosarcoma), and other tumor types that can occur primarily in the liver (PEComa/angiomyolipoma, inflammatory pseudotumor-like follicular dendritic cell sarcoma, EBV-associated smooth muscle tumor, inflammatory myofibroblastic tumor, malignant rhabdoid tumor). Lastly, I discuss metastatic sarcomas to the liver, as well as pitfalls presented by metastatic melanoma and sarcomatoid carcinoma.

Cadmium, von Willebrand factor and vascular aging

Vascular aging is a major contributing factor to cardiovascular disease. The aged blood vessels, characterized by vascular wall thickening and stiffening, are instigated by endothelial cell dysfunction induced by oxidative stress and inflammation. von Willebrand Factor (vWF) is a glycoprotein known for its role in coagulation, and plasma levels of vWF are increased with age. Elevated vWF promotes thrombosis, atherosclerotic plaque formation, inflammation and proliferation of vascular smooth muscle cells. Cadmium (Cd) is an environmental pollutant associated with increased morbidity and mortality of cardiovascular disease. At low concentrations, Cd activates pro-survival signaling in endothelial cells, however enhances intima-media thickness and atherogenesis. A non-cytotoxic dose of Cd also increases endothelial vWF expression and secretion in vivo and in vitro. In this review, we summarize the molecular mechanisms underlying vWF-promoted vascular aging-associated pathologies and Cd-induced vWF expression. In addition, we propose that exposure to low-dose Cd is a risk factor for vascular aging, through elevation of plasma vWF.

Angiosarcoma of the visceral organs: A morphological, immunohistochemical, and C-MYC status analysis

Visceral angiosarcomas are rare malignant tumors with poor prognosis. The pathogenesis remains unclear. Herein, we describe the morphological, immunohistochemical, and C-MYC status of a series of visceral angiosarcomas. We evaluated the clinicopathologic and C-MYC status of visceral angiosarcomas (n = 12) and compared them to a control series of angiosarcomas arising in cutaneous (n = 15) and soft tissue structures (n = 15). Clinical follow-up data were obtained for all patients and exhibited high metastasis and mortality rates. Malignant endothelial cells displayed a range of morphological features including nonepithelioid, epithelioid, and mixed features, forming vasoformative (n = 6), solid (n = 4) or mixed (n = 2) architectures. Epithelioid morphology was present in 4/12 tumors. Mitoses ranged from 3 to 60 per 10 high-power fields. Necrosis was observed in 10/12 tumors. By immunohistochemistry, all angiosarcomas expressed at least 2 markers of endothelial differentiation, including CD31, CD34, vWF, ERG, and Fli-1. Eight cases of C-MYC amplification and 5 cases of C-MYC translocation were detected. Our data showed that visceral angiosarcoma is more common in women, and the clinical presentations of patient age and tumor size were significantly different between the study and control groups. No significant difference in staining between the visceral angiosarcoma and control groups was observed for endothelial markers, while different C-MYC statuses were detected.

IMP3 overexpression occurs in various important cancer types and is linked to aggressive tumor features: A tissue microarray study on 8,877 human cancers and normal tissues

IMP3 is an RNA binding protein required for ribosomal RNA processing, which has been suggested to be a prognostic marker in a large variety of human types of cancer. However, available data on the prevalence of IMP3 expression are largely discrepant. To systematically investigate the epidemiology and clinical relevance of IMP3 expression in human cancers we employed a two-step tissue microarrays (TMAs) approach. First, a normal tissue TMA and a multi-tumor TMA were analyzed for immunohistochemically detectable expression of IMP3 in 76 different normal tissue types and 3889 cancer samples from 95 different tumor categories. In a second step, we searched for associations between IMP3 expression and tumor phenotype and patient prognosis in TMAs containing 697 urinary bladder cancers, 1711 colon cancers, 343 esophageal adenocarcinomas, 251 esophageal squamous cell cancers, 673 lung cancers), 275 pancreatic cancers and 230 stomach cancers. In normal tissues, unequivocal IMP3 expression was found in placenta, lymphocytes and some types of glandular epithelial cells. In cancers, at least one case with weak expression could be found in 76 out of 95 (80%) different tumor types and 64 entities (67%) had at least one tumor with strong positivity. IMP3 expression was most frequently found in testicular cancer (including 71% seminomas and 96% non-seminomas), neuroblastoma (88%), and squamous cell cancer of various origins. Significant associations were found between IMP3 and adverse tumor features in esophageal adenocarcinomas and cancers of the urinary bladder, lung, stomach, and pancreas. In summary, IMP3 was frequently expressed in many different tumor types, and was typically associated with aggressive tumor features.

Prevalence of βIII-tubulin (TUBB3) expression in human normal tissues and cancers

Microtubules are multifunctional cytoskeletal proteins that are involved in crucial cellular roles including maintenance of cell shape, intracellular transport, meiosis, and mitosis. Class III beta-tubulin (βIII-tubulin, also known as TUBB3) is a microtubule protein, normally expressed in cells of neuronal origin. Its expression was also reported in various other tumor types, such as several types of lung cancer, ovarian cancer, and esophageal cancer. TUBB3 is of clinical relevance as overexpression has been linked to poor response to microtubule-targeting anti-cancer drugs such as taxanes. To systematically investigate the epidemiology of TUBB3 expression in normal and neoplastic tissues, we used tissue microarrays for analyzing the immunohistochemically detectable expression of TUBB3 in 3911 tissue samples from 100 different tumor categories and 76 different normal tissue types. At least 1 tumor with weak expression could be found in 93 of 100 (93%) different tumor types, and all these 93 entities also had at least 1 tumor with strong positivity. In normal tissues, a particularly strong expression was found in neurons of the brain, endothelium of blood vessels, fibroblasts, spermatogenic cells, stroma cells, endocrine cells, and acidophilic cells of the pituitary gland. In tumors, strong TUBB3 expression was most frequently found in various brain tumors (85%-100%), lung cancer (35%-80%), pancreatic adenocarcinoma (50%), renal cell carcinoma (15%-80%), and malignant melanoma (77%). In summary, these results identify a broad spectrum of cancers that can at least sporadically express TUBB3. Testing of TUBB3 in cancer types eligible for taxane-based therapies could be helpful to identify patients who might best benefit from this treatment.

Trends in Gene Expression Profiling for Prostate Cancer Risk Assessment: A Systematic Review

OBJECTIVES

The aim of the study is to review biotechnology advances in gene expression profiling on prostate cancer (PCa), focusing on experimental platform development and gene discovery, in relation to different study designs and outcomes in order to understand how they can be exploited to improve PCa diagnosis and clinical management.

METHODS

We conducted a systematic literature review on gene expression profiling studies through PubMed/MEDLINE and Web of Science between 2000 and 2016. Tissue biopsy and clinical gene profiling studies with different outcomes (e.g., recurrence, survival) were included.

RESULTS

Over 3,000 papers were screened and 137 full-text articles were selected. In terms of technology used, microarray is still the most popular technique, increasing from 50 to 70% between 2010 and 2015, but there has been a rise in the number of studies using RNA sequencing (13% in 2015). Sample sizes have increased, as well as the number of genes that can be screened all at once, but we have also observed more focused targeting in more recent studies. Qualitative analysis on the specific genes found associated with PCa risk or clinical outcomes revealed a large variety of gene candidates, with a few consistent cross-studies.

CONCLUSIONS

The last 15 years of research in gene expression in PCa have brought a large volume of data and information that has been decoded only in part, but advancements in high-throughput sequencing technology are increasing the amount of data that can be generated. The variety of findings warrants the execution of both validation studies and meta-analyses. Genetic biomarkers have tremendous potential for early diagnosis of PCa and, if coupled with other diagnostics (e.g., imaging), can effectively be used to concretize less-invasive, personalized prediction of PCa risk and progression.

Copy number variation in archival melanoma biopsies versus benign melanocytic lesions

BACKGROUND

Skin melanocytes can give rise to benign and malignant neoplasms. Discrimination of an early melanoma from an unusual/atypical benign nevus can represent a significant challenge. However, previous studies have shown that in contrast to benign nevi, melanoma demonstrates pervasive chromosomal aberrations.

OBJECTIVE

This substantial difference between melanoma and benign nevi can be exploited to discriminate between melanoma and benign nevi.

METHODS

Array-comparative genomic hybridization (aCGH) is an approach that can be used on DNA extracted from formalin-fixed paraffin-embedded (FFPE) tissues to assess the entire genome for the presence of changes in DNA copy number. In this study, high resolution, genome-wide single-nucleotide polymorphism (SNP) arrays were utilized to perform comprehensive and detailed analyses of recurrent copy number aberrations in 41 melanoma samples in comparison with 21 benign nevi.

RESULTS

We found statistically significant copy number gains and losses within melanoma samples. Some of the identified aberrations are previously implicated in melanoma. Moreover, novel regions of copy number alterations were identified, revealing new candidate genes potentially involved in melanoma pathogenesis.

CONCLUSIONS

Taken together, these findings can help improve melanoma diagnosis and introduce novel melanoma therapeutic targets.

Diagnostic Immunohistochemistry in Cutaneous Neoplasia: An Update

Immunohistochemistry (IHC) is an important adjunct in the diagnosis of neoplastic skin diseases. In addition to the many established IHC markers currently in use, new markers continue to emerge, although their general acceptance and routine application requires robust validation. Here, we summarize the most well-established and commonly used biomarkers along with an array of newer ones reported in the past several decades that either demonstrate or hold high clinical promise in the field of cutaneous pathology. We also highlight recent applications of novel IHC markers in melanoma diagnosis including genetic mutation status markers [e.g. BRAF (v-raf murine sarcoma viral oncogene homolog B) and NRAS (neuroblastoma RAS viral oncogene homolog)] and an epigenetic alteration marker (e.g. 5-hydroxymethylcytosine). We specifically focus on the role of IHC in the differential diagnosis of cutaneous lesions that fall under the following categories: melanoma, epidermal tumors with an intraepidermal epitheliomatous pattern, spindle cell lesions of the dermis, small round blue cell tumors of the dermis, and cutaneous adnexal tumors. While IHC is a valuable tool in diagnostic dermatopathology, marker selection and interpretation must be highly informed by clinical context and the histologic differential diagnosis. With rapid progress in our understanding of the genetic and epigenetic mechanisms of tumorigenesis, new IHC markers will continue to emerge in the field of diagnostic dermatopathology.

ERG expression in prostate cancer: the prognostic paradox

BACKGROUND

TMPRSS2/ERG fusion resulting in ERG overexpression occurs in 30 to 50% of prostate cancer (PCa) in Caucasian patients, but its prognostic relevance remains controversial. In the present study, we investigated ERG expression in all stages of PCa progression, and evaluated the prognostic impact of ERG status in clinically localized PCa (CLC) and in castration resistant disease (CRPC).

METHODS

ERG and AR expressions were evaluated by immunohistochemistry on tissue microarrays containing samples of high grade PIN (n = 57), CLC surgically treated (n = 299, including 185 Caucasians and 114 African-Caribbeans), metastases (n = 17), and CRPC (n = 41).

RESULTS

In Caucasians, ERG expression significantly increased from high grade PIN (17.5%) to pT2 (27%) and pT3 CLC (43%), then to metastases (53%). In CLC, stainings for ERG and AR were correlated, and ERG expression was less frequent in African-Caribbeans compared to Caucasians (11.5% vs. 33%). In Caucasians CLC, ERG was associated with longer recurrence free survival, after adjusting for classical prognostic markers. In CRPC, ERG was expressed in 29% of cases, and was associated with a longer overall survival.

CONCLUSIONS

Our results confirm that ERG expression is less frequent in PCa from patients of African descent. Although ERG expression increases during PCa natural history, positive ERG status is associated with better outcome in both CLC and CRPC. This paradox could be explained in part by the fact that ERG expression is AR dependant, then ERG positive cancers are likely to progress in a rich androgen environment, with a better response to androgen suppression.

The utility of ERG, CD31 and CD34 in the cytological diagnosis of angiosarcoma: an analysis of 25 cases

AIMS

Erythroblast transformation specific related gene (ERG), a proto-oncogene member of the erythroblast transformation specific transcription factor family, is a sensitive marker of endothelial differentiation and is expressed in vascular tumours, including angiosarcomas (AS). Immunohistochemistry is necessary for the diagnosis of AS in fine needle aspirates where low cellularity and lack of preserved tissue architecture impedes diagnosis. The aim of this study was to assess the utility of an ERG-enriched immunohistochemistry panel in the cytological diagnosis of AS.

METHODS

25 AS diagnosed on fine needle aspirates were stained for ERG, CD31, CD34, and AE1/AE3. Staining intensity and percentage tumour cell positivity were evaluated. Spearman's correlation was assessed for significant correlations between antibodies.

RESULTS

Sensitivities for ERG, CD31, CD34 and AE1/AE3 were 100%, 100%, 60% and 21%, respectively. Spearman's analysis revealed that ERG and CD31 staining correlated significantly; there was no significant correlation between CD31 and CD34 staining.

CONCLUSIONS

With equal sensitivity to, and strong correlation with CD31, ERG staining is highly suitable for the cytological diagnosis of AS. ERG and CD31 are more sensitive vascular markers than CD34. ERG, a nuclear stain, complements the cytoplasmic/membranous staining of CD31. Used in conjunction with CD31, ERG can corroborate the diagnosis of AS.

ERG protein expression as a biomarker of prostate cancer

TMPRSS2-ERG is a recurrent rearrangement specific for prostate cancer, leading to the overexpression of a truncated ERG protein product that is amenable to immunohistochemical detection. Two monoclonal anti-ERG antibodies have currently been validated, with comparable sensitivity and specificity for detecting ERG rearrangement. ERG immunostaining has been applied in different settings to elucidate the role of ERG rearrangement and overexpression in prostate cancer tumorigenesis and progression, as well as to investigate potential diagnostic and prognostic applications. In this article we review the literature on the topic and suggest potential future applications.

Newly Available Antibodies With Practical Applications in Surgical Pathology

Selected antibodies that have become available in recent years and have applications in diagnostic pathology are discussed. They include antibodies that are organ-related, provide information on cellular differentiation or histogenetic type, have predictive value in tumors, and highlight infective agents. PAX8 (paired box gene 8) is a marker expressed in the lower female genital tract, thyroid, and kidney and their tumors. Napsin A is expressed in the lung and kidney and is an alternative marker for pulmonary adenocarcinoma. Arginase A is a sensitive and specific marker for liver tumors. ERG (Ets-related gene) is an excellent marker for endothelium and vascular tumors as well as prostatic cancer (about 50% of cases). SOX10 (SRY-related HMG box) is expressed predominantly in melanocytic and Schwann cells and the corresponding tumors. DOG1 (discovered on GIST 1) is an excellent marker for gastrointestinal stromal tumor (GIST) and acinic cell carcinoma. OCT3/4 is a pan–germ cell tumor marker, except yolk sac tumor. SALL4 is positive in various types of germ cell tumors, including yolk sac tumor. MUC4 (mucin-related antigen 4) is a sensitive and specific marker for low-grade fibromyxoid sarcoma. Langerin is a specific marker for Langerhans cells and their tumors. SOX11 is a sensitive marker for mantle cell lymphoma. New generation antibodies against anaplastic lymphoma kinase (ALK) are required to reliably demonstrate ALK gene translocation in pulmonary carcinomas. Lack of expression of succinate dehydrogenase B is seen in paragangliomas of the hereditary form and in the pediatric type of GIST. Antibodies against Trepenoma pallidum can facilitate the diagnosis of syphilis, whereas those against SV40 (simian virus 40) are helpful for diagnosis of BK virus infection and progressive multifocal leukoencephalopathy.

HPIP is upregulated in liver cancer and promotes hepatoma cell proliferation via activation of G2/M transition

Hematopoietic pre-B-cell leukemia transcription factor (PBX)-interacting protein (HPIP) has been shown to play a role in cancer development and progression. However, the detailed role of HPIP in cancer cell growth and the exact mechanism by which HPIP regulates cancer cell proliferation remains unclear. Here, we report that HPIP is overexpressed in most of 328 liver cancer patients and regulates hepatoma cell proliferation through G2/M checkpoint activation. HPIP increased anchorage-dependent and -independent growth of human liver cancer cell lines. The amino acid region 531-631 of HPIP was important for its modulation of liver cancer cell growth. The increased effects of HPIP on liver cancer cell proliferation were associated with activation of the G2/M cell-cycle concomitant with a marked increase of cyclin B1 and the inhibition of the negative G2/M phase regulator GADD45α. HPIP knockdown dramatically suppressed the growth of HepG2 liver cancer cells in nude mice. These data highlight the important role of HPIP in liver cancer cell growth and suggest that HPIP may be a good target for liver cancer therapy.

Usefulness of a monoclonal ERG/FLI1 antibody for immunohistochemical discrimination of Ewing family tumors

Ewing family tumors (EFTs) and prostate carcinomas are characterized by rearrangement of ETS genes, most commonly FLI1 (EFTs) and ERG (prostate carcinomas). Previously, we characterized an antibody against ERG (EPR3864) for detecting ERG-rearranged prostate carcinoma. Because EPR3864 also cross-reacts with FLI1, we evaluated the usefulness of EPR3864 for discriminating EFTs from other small round blue cell tumors (SRBCTs) with immunohistochemistry. Of 57 evaluable EFTs, 47 (82%) demonstrated at least moderate, diffuse, nuclear ERG/FLI1 staining (including 89% and 100% of cases with confirmed EWSR1:FLI1 and EWSR1:ERG fusions, respectively), of which 1, 3, and 43 showed negative, cytoplasmic, or membranous CD99 staining, respectively. Among other SRBCTs (61 cases, 7 types), at least moderate, diffuse, nuclear EPR3864 staining was seen in all precursor B-lymphoblastic lymphomas/leukemias and subsets of Burkitt lymphomas (10%) and synovial sarcomas (45%). In summary, EPR3864 may be useful in detecting EWSR1:FLI1 and EWSR1:ERG rearranged EFTs in addition to prostate carcinomas.

TMPRSS2-ERG rearrangement in dominant anterior prostatic tumours: incidence and correlation with ERG immunohistochemistry

AIM

To study prostate cancer zonal differences in TMPRSS2-ERG gene rearrangement.

METHODS AND RESULTS

We examined 136 well-characterized dominant anterior prostatic tumours, including 61 transition zone (TZ) and 75 anterior peripheral zone (PZ) lesions, defined using strict anatomical considerations. TMPRSS2-ERG FISH and ERG protein immunohistochemistry were performed on tissue microarrays. FISH results, available for 56 TZ and 71 anterior PZ samples, were correlated with ERG staining and TZ-associated 'clear cell' histology. Fewer TZ cancers (four of 56; 7%) were rearranged than anterior PZ cancers (18 of 71; 25%) (P = 0.009); deletion was the sole mechanism of TZ cancer rearrangement. ERG protein overexpression was present in 4% (two of 56; both FISH+) and 30% (21 of 71; 17 FISH+) of TZ and anterior PZ tumours, respectively. 'Clear cell' histology was present in 21 of 56 (38%) TZ and eight of 71 (11%) anterior PZ tumours. Seven per cent of cancers with and 21% without this histology had rearrangement, regardless of zonal origin.

CONCLUSIONS

TMPRSS2-ERG rearrangement occurs in dominant TZ and anterior PZ prostate cancers, with all rearranged TZ cancers in this cohort showing deletion. ERG immunohistochemistry demonstrated excellent sensitivity (86%) and specificity (96%) for TMPRSS2-ERG rearrangement. TMPRSS2-ERG fusion is rare in TZ tumours and present at a low frequency in tumours displaying 'clear cell' histology.

ERG induces epigenetic activation of Tudor domain-containing protein 1 (TDRD1) in ERG rearrangement-positive prostate cancer

Background

Overexpression of ERG transcription factor due to genomic ERG-rearrangements defines a separate molecular subtype of prostate tumors. One of the consequences of ERG accumulation is modulation of the cell’s gene expression profile. Tudor domain-containing protein 1 gene (TDRD1) was reported to be differentially expressed between TMPRSS2:ERG-negative and TMPRSS2:ERG-positive prostate cancer. The aim of our study was to provide a mechanistic explanation for the transcriptional activation of TDRD1 in ERG rearrangement-positive prostate tumors.

Methodology/Principal Findings

Gene expression measurements by real-time quantitative PCR revealed a remarkable co-expression of TDRD1 and ERG (r² = 0.77) but not ETV1 (r²<0.01) in human prostate cancer in vivo. DNA methylation analysis by MeDIP-Seq and bisulfite sequencing showed that TDRD1 expression is inversely correlated with DNA methylation at the TDRD1 promoter in vitro and in vivo (ρ = −0.57). Accordingly, demethylation of the TDRD1 promoter in TMPRSS2:ERG-negative prostate cancer cells by DNA methyltransferase inhibitors resulted in TDRD1 induction. By manipulation of ERG dosage through gene silencing and forced expression we show that ERG governs loss of DNA methylation at the TDRD1 promoter-associated CpG island, leading to TDRD1 overexpression.

Conclusions/Significance

We demonstrate that ERG is capable of disrupting a tissue-specific DNA methylation pattern at the TDRD1 promoter. As a result, TDRD1 becomes transcriptionally activated in TMPRSS2:ERG-positive prostate cancer. Given the prevalence of ERG fusions, TDRD1 overexpression is a common alteration in human prostate cancer which may be exploited for diagnostic or therapeutic procedures.

Clinical applications of novel ERG immunohistochemistry in prostate cancer diagnosis and management

TMPRSS2:ERG gene fusions, the most common molecular subtype of ETS family gene fusions occur in ~50% of prostate carcinomas (PCas) and ~20% of high-grade prostatic intraepithelial neoplasia (HGPIN) intermingled with adjacent PCa demonstrating identical gene fusions. ERG gene fusions have not yet been demonstrated in isolated benign prostate tissue, isolated high-grade prostatic intraepithelial neoplasia, or benign cancer mimics. Taken together, ERG gene fusions are the most prostate cancer-specific biomarker yet identified and define a specific molecular subtype of PCa with important clinical and biological implications. ERG gene fusions result in the overexpression of a chimeric fusion transcript that encodes a truncated ERG protein product. Recently, N-terminal epitope-targeted mouse (9FY) and C-terminal-targeted rabbit monoclonal (EPR 3864) ERG antibodies are commercially available and are increasingly utilized as a surrogate for TMPRSS2:ERG gene fusions. Until recently, because of lack of availability of reliable ERG antibody, the most commonly utilized methods for studying ERG aberrations in PCa specimens included fluorescence in situ hybridization or reverse transcriptase polymerase chain reaction. The knowledge gleaned from these studies has significantly improved our understanding of molecular biology of ERG gene fusions. With availability of highly specific anti-ERG monoclonal antibodies, there are now unprecedented opportunities to explore and validate clinical applications of ERG antibody in routine pathology practice, which has just started. This review provides a brief background of molecular biology of ERG gene fusions in PCa and focuses on characterizing the current state of ERG oncoprotein and determining the role of ERG immunohistochemistry in the diagnosis and biological stratification of prostate cancer.