Search

Pigmented epithelioid melanocytoma (PEM) represents a group of rare, heavily pigmented melanocytic tumors encompassing lesions previously designated as "animal-type melanomas" and "epithelioid blue nevi." Despite the association of multiple such tumors in the setting of Carney complex, most cases of PEM occur spontaneously as solitary neoplasms in otherwise healthy patients. PEM may arise in both children and adults, and has a known propensity to spread to the regional lymph nodes. Despite this latter finding, recurrence at the biopsy site or spread beyond the lymph node basin is exceptionally uncommon. Although the molecular basis for PEM continues to be characterized, findings to date suggest that this category of melanocytic neoplasia has genetic alterations distinct from those seen in common nevi, dysplastic nevi, Spitz nevi, and melanoma. Herein, we present an in-depth clinical, histopathologic, and molecular analysis of a case of PEM occurring on the scalp of a young African American girl found to have a novel NTRK3-SCAPER gene fusion.

Aim Primary cutaneous neuroendocrine carcinoma, or Merkel cell carcinoma (MCC), cannot be distinguished morphologically from small-cell neuroendocrine carcinomas (SmCC) from other sites. Immunohistochemistry is required to confirm cutaneous origin, and is also used for detection of sentinel lymph node (SLN) metastases of MCC. Cytokeratin 20 (CK20) expression is commonly used for these purposes, but is negative in some MCC cases, and has unclear specificity. We evaluated immunohistochemistry for neurofilament and CK20 in MCC compared with SmCC from other sites. Methods and results We evaluated neurofilament expression in 55 MCC specimens from 39 unique patients, including nine CK20-negative MCC tumours. Neurofilament expression was observed in 42 of 55 (76.4%) MCC cases, including seven of nine (77.8%) CK20-negative MCC cases. Neurofilament was expressed in nine of 12 (75%) Merkel cell polyomavirus-positive tumours and five of 10 (50%) virus-negative tumours. Compared to a standard immunohistochemical panel (cytokeratin cocktail and CK20), neurofilament was 87.5% sensitive for detecting SLN metastases. Neurofilament and CK20 expression was also assessed in 61 extracutaneous SmCC from 60 unique patients, with primary sites including lung (27), bladder (18), cervix (3), gastrointestinal tract (3), sinonasal tract (2) and other sites (7). The specificity of neurofilament and CK20 for MCC versus non-cutaneous SmCC was 96.7% and 59.0%, respectively. Conclusions Neurofilament has superior specificity to CK20 in distinguishing MCC from non-cutaneous SmCC. Neurofilament is frequently expressed in CK20- and virus-negative MCC tumours. Limitations of neurofilament immunohistochemistry include lower sensitivity than CK20 and subtle staining in some tumours. However, our findings indicate that neurofilament is useful for excluding non-cutaneous SmCC.

Prostate cancer (PCa) is one of the most frequently diagnosed cancers among men. Many molecular changes have been detailed during PCa progression. The gene encoding the transcription factor ERG shows recurrent rearrangement, resulting in the overexpression of ERG in the majority of prostate cancers. Overexpression of ERG plays a critical role in prostate oncogenesis and development of metastatic disease. Among the downstream effectors of ERG, Frizzled family member FZD4 has been shown to be a target of ERG. Frizzled-8 (FZD8) has been shown to be involved in PCa bone metastasis. In the present study, we show that the expression of FZD8 is directly correlated with ERG expression in PCa. Furthermore, we show that ERG directly targets and activates FZD8 by binding to its promoter. This activation is specific to ETS transcription factor ERG and not ETV1. We propose that ERG overexpression in PCa leads to induction of Frizzled family member FZD8, which is known to activate the Wnt pathway. Taken together, these findings uncover a novel mechanism for PCa metastasis, and indicate that FZD8 may represent a potential therapeutic target for PCa.

Aims Pseudosarcomatous myofibroblastic proliferations of the genitourinary tract have a debatable relationship with inflammatory myofibroblastic tumour (generally lacking ALK rearrangement); however, they share several overlapping features with nodular fasciitis of soft tissue. As rearrangement of the USP6 gene has been recently recognised as a recurrent alteration in soft tissue nodular fasciitis, and several other alternative gene fusions have been recently recognised in inflammatory myofibroblastic tumour, the aim of this study was to investigate whether USP6, ROS1 or ETV6 rearrangements were present in these lesions (12 cases). Methods and results Fluorescence in-situ hybridisation analysis was performed by the use of bacterial artificial chromosome-derived break-apart probes against USP6, ROS1, and ETV6. Two cases with adequate genetic material from recent paraffin tissue blocks were also tested by use of a solid tumour gene fusion detection assay via next-generation sequencing, targeting >50 known genes involved in recurrent fusions. None of the genitourinary pseudosarcomatous myofibroblastic proliferations was found to harbour USP6 (0/12), ROS1 (0/8) or ETV6 (0/7) rearrangements, and no gene fusions were detected in two cases studied by sequencing. Conclusions Despite overlap in histological and immunohistochemical features between pseudosarcomatous myofibroblastic proliferation and nodular fasciitis, these tumours lack the recently recognised USP6 rearrangements that occur in nodular fasciitis, as well as alternative fusions found in ALK-negative inflammatory myofibroblastic tumours. At present, this diagnosis remains based primarily on clinical, histological and immunohistochemical features.

A highly sensitive microfluidic system to capture circulating tumor cells from whole blood of cancer patients is presented. The device incorporates graphene oxide into a thermoresponsive polymer film to serve as the first step of an antibody functionalization chemistry. By decreasing the temperature, captured cells may be released for subsequent analysis.

Background Targeted sequencing of patients with epidemiologically low-risk (ELR) head and neck squamous cell carcinoma (HNSCC) could help identify novel drivers or lost suppressors leading to precision medicine protocols and improved survival rates. Methods A patient with ELR-HNSCC was selected for targeted sequencing. We then assessed next generation sequencing cohorts from the Oncomine Powertool Database, which contains pan-cancer data from The Cancer Genome Atlas (TCGA). Results Targeted sequencing revealed fibroblast growth factor receptor-1 (FGFR1) amplifications as a putative driver of the patient's tumor. Patients with HNSCC from TCGA data demonstrated fibroblast growth factor (FGF) family mutations, rearrangements, or amplifications in over 35% of HNSCC cases, with a statistically significant higher frequency in African American populations. FGF alterations were unique from activating phosphatidylinositol 3-kinase (PIK3CA) mutations. Conclusion Together, these data suggest that FGF signaling may be critical for a subset of patients with HNSCC independent of other known pathways and provides rationale for leveraging patients with ELR-HNSCC to define molecular subsets of high-risk HNSCC. © 2016 Wiley Periodicals, Inc. Head Neck, 2016

Cutaneous spindle cell malignancies such as sarcomatoid squamous cell carcinoma (SCC), leiomyosarcoma, desmoplastic melanoma (DM) and atypical fibroxanthoma (AFX) may be morphologically indistinguishable, yet accurate diagnosis is important for appropriate clinical management. The distinction among these entities relies on immunohistochemical evaluation for epidermal, muscle or melanocytic differentiation. Epidermal differentiation markers include cytokeratins and p63. p63 is expressed as two distinct isoforms, ΔNp63 (p40) and TAp63. p40 positivity is highly specific for pulmonary SCC and head and neck sarcomatoid SCC. We examined the utility of p40 vs. p63 immunostaining in the differentiation of a variety of cutaneous spindle cell malignancies, including sarcomatoid SCC (n = 27), AFX (n = 34) and DM (n = 10). p40 was less sensitive than p63 for detecting sarcomatoid SCC (56% and 81%, respectively). p63 and p40 were comparably specific for sarcomatoid SCC relative to AFX, with only rare weak staining of tumor cells for p63 and/or p40 in a minority of AFX cases, including one case with approximately 10% of cells staining weakly for p40. All cases of DM were negative for p40 and p63. Our results support continued use of p63 for diagnosis of cutaneous sarcomatoid SCC because of greater sensitivity relative to p40.

BACKGROUND Family history of prostate cancer is a well-recognized risk factor. Previous linkage studies have reported a putative prostate cancer susceptibility locus at chromosome 17q21–22. SPOP (Speckle-type POZ protein) maps to the 17q21–22 candidate linkage region and is one of the most frequently mutated genes in sporadic prostate cancers. METHODS We performed targeted next generation sequencing to analyze 2009 exons from 202 genes in a candidate linkage region on chromosome 17q21–22 using 94 unrelated familial prostate cancer cases from the University of Michigan Prostate Cancer Genetics Project (n = 54) and Johns Hopkins University (n = 40) including the exons and UTRs of SPOP. RESULTS We identified a novel SPOP missense mutation (N296I) in a man with prostate cancer diagnosed at age 43. This mutation completely segregates with prostate cancer affection status among the men in this family. The N296I mutation resides within the evolutionarily conserved Bric-a-brac, Tramtrack, Broad-complex (BTB) domain, involved in recruiting targets to Cul3 for degradation. Analysis of the prostate tumor from this individual verified the presence of heterozygous N296I as well as an ERG fusion. CONCLUSIONS We have discovered a novel mutation in SPOP that tracks with prostate cancer within a family and is predicted to be deleterious. Taken together, our results implicate SPOP as a candidate gene for hereditary prostate cancer. Prostate 74:983–990, 2014. © 2014 Wiley Periodicals, Inc.

A study was undertaken to correlate telomere dysfunction and genomic instability with the histopathological grades and the estrogen and progesterone receptor status in breast cancer. Sixty-one archived breast tissues (38 cancer tissues and 23 paired normal tissues) were used in the study. The breast tumor tissues showed significantly shorter telomeres (7.7 kb) compared with the paired adjacent tissues (9.0 kb) by Southern blot analysis. Moreover, telomere shortening was more significant in Grade III tumors than in the Grade II tumors (P 5 0.05). Quantitative fluorescence in situ hybridization on paraffin tissue sections revealed a similar trend in telomere shortening. Telomere attrition was associated with telomere dysfunction as revealed by the presence of significantly higher anaphase bridges in tumor cells which was tumor grade dependent. Furthermore, estrogen receptive negative tumors displayed higher anaphase and internuclear bridges. Selected samples from each grade showed greater genomic imbalances in the higher grades than the lower grade tumors as detected by array-comparative genomic hybridization. Telomerase activity was found to be higher in the higher grades (Grade II and III) compared with the lower grade (Grade I). The average mRNA expression of TRF1 and POT1 was lower in the tumor tissues than in the normal tissues. Tankyrase 1 mRNA expression showed a grade-dependent increase in tumor tissues and its expression was also high in estrogen and progesterone negative tumors. The data support the notion that telomere dysfunction might be of value as a marker of aggressiveness of the tumors in breast cancer patients. V C 2008 Wiley-Liss, Inc.

The identification of specific oncogenes and tumor suppressor genes in regions of recurrent aneuploidy is a major challenge of molecular cancer research. Using both oligonucleotide single-nucleotide polymorphism and mRNA expression arrays, we integrated genomic and transcriptional information to identify and prioritize candidate cancer genes in regions of increased and decreased chromosomal copy number in a cohort of primary breast cancers. Confirming the validity of this approach, several regions of previously-known copy number (CN) alterations in breast cancer could be successfully reidentified. Focusing on regions of decreased CN, we defined a prioritized list of eighteen candidate genes, which included ARPIN, FBN1, and LZTS1, previously shown to be associated with cancers in breast or other tissue types, and novel genes such as P29, MORF4L1, and TBC1D5. One such gene, the RUNX3 transcription factor, was selected for further study. We show that RUNX3 is present at reduced CNs in proportion to the rest of the tumor genome and that RUNX3 CN reductions can also be observed in a breast cancer series from a different center. Using tissue microarrays, we demonstrate in an independent cohort of over 120 breast tissues that RUNX3 protein is expressed in normal breast epithelium but not fat and stromal tissue, and widely down-regulated in the majority of breast cancers (>85%). In vitro, RUNX3 overexpression suppressed the invasive potential of MDA-MB-231 breast cancer cells in a matrigel assay. Our results demonstrate the utility of integrative genomic approaches to identify novel potential cancer-related genes in primary tumors. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat.

Summary objective Strong evidence indicates that at least one key tumour suppressor gene important for the development of malignant parathyroid tumours is located on chromosome 13, but the critical target gene remains unknown. Importantly, the region of acquired DNA loss includes two established tumour suppressor genes, the retinoblastoma gene, RB (RB1) and BRCA2. Resolution of whether RB or BRCA2 is the critical 13q tumour suppressor gene in parathyroid cancer requires analysis of these genes’ sequences for intragenic inactivating mutations. Therefore, RB and BRCA2 were analysed in a group of parathyroid carcinomas in which mutations of these genes should be most readily detectable. patients and design Six parathyroid carcinomas from four patients which showed loss of heterozygosity (LOH) at the RB locus and/or 13q loss by comparative genomic hybridazation (CGH) were selected from a CGH/LOH-screened panel of 16 carcinoma specimens from 10 patients. These tumours were examined for mutations by direct sequencing of the complete 27-exon coding region, intron–exon boundaries and promoter of RB. The 26 coding exons and intron–exon boundaries of BRCA2 were also directly sequenced in seven parathyroid carcinomas with loss in the BRCA2 region. results No microdeletions, insertions, or point mutations were detected in either RB or BRCA2 in any of the carcinomas. conclusion The absence of tumour-specific somatic mutations in RB and BRCA2 suggests that they are unlikely to act as classic tumour suppressor genes in the pathogenesis of parathyroid carcinomas. While decreased expression of these genes might contribute to parathyroid carcinomatosis in a secondary fashion and 13q loss warrants further study as a diagnostic marker for parathyroid carcinoma, the putative 13q tumour suppressor awaits identification.

To address the possible genetic relationship between primary mediastinal large-B-cell lymphoma (PMLBCL) and diffuse large-B-cell lymphoma (DLBCL), we compared DNA copy number changes identified by comparative genomic hybridization (CGH) analysis of 40 PMLBCL and 91 DLBCL tumors. We assessed their karyotypes by G-banding; amplification of MYC, BCL2, and REL genes by Southern blotting; and incidence of nonpolymorphic BCL6 mutations by single-strand conformation polymorphism analysis (SSCP). Overall, CGH identified overlapping and nonoverlapping patterns of DNA copy number changes in the two groups. Among the latter changes, gains of chromosomes 8, 11, 15, and 16 and losses of chromosomes 5, 10, 15, 16, 17, and 20 were seen only in DLBCL, and gains of chromosomes 10, 21, and 22 and losses of chromosomes 11, 13, and 18 were seen only in PMLBCL. Several overlapping changes were identified in both groups, with variation in incidence. Statistical analysis of these changes showed significant gains of chromosomes 3 (P ≤ 0.05) and 7q (P ≤ 0.05) in DLBCL and gains of chromosomes 9 (P ≤ 0.05) and 19 (P ≤ 0.05) and the X chromosome (P ≤ 0.05) and loss of chromosome 4 (P ≤ 0.05) in PMLBCL. Frequent recurring DNA amplification at 2p13-15 and less frequent amplification at 6p21, 12q13, and 18q21 were noted in both groups. Recurring amplification at 1q21 was seen only in DLBCL, whereas nonrecurring amplification at 10p11.2 and 15q22-24 was seen only in PMLBCL. G-banded karyotype analysis identified t(3;14)(q27;q32) in one and t(14;18)(q32;q21) in two cases of PMLBCL. Seven of 13 cases exhibited SSCP variants in the 5′ noncoding region of BCL6. In addition, 19 of 24 PMLBCLs assayed for BCL6 protein expression by immunohistochemistry showed positive results, indicating an origin from a germinal center (GC)–derived B cell. Based on these data, we conclude that PMLBCL is a distinct entity among GC-derived high-grade DLBCLs. © 2002 Wiley-Liss, Inc.

Killer cell inhibitory receptors (KIR) belong to the immunoglobulin superfamily of molecules and are expressed on natural killer (NK) cells. The KIRs of the p58/p50 family have two immunoglobulin domains and are ligands for HLA-Cw antigens, whereas the p70/p70 delta family has three immunoglobulin domains and comprises ligands for HLA-B antigens and possibly some HLA-A antigens. Members of a third KIR family, KIR103, have two immunoglobulin domains but have highest nucleotide sequence homology to the p70 family. The ligands for KIR103 on target cells are currently unknown. We here report the complete genomic organization of KIR103. It spans about 12 kb of DNA and consists of eight exons of which exon 1 and exon 2 encode the leader sequence. Exon 3 encodes the first immunoglobulin domain (gamma 1), and exon 4 encodes the main part of the second immunoglobulin domain (gamma 3), which also contains sequences contributed by exon 5 and exon 6. Exon 6 encodes the transmembrane domain, whereas exons 7 and 8 encode most of the cytoplasmic domain. KIR103 is polymorphic, and two alleles, 103AS and 103LP, are defined in this study. Additional full-length cDNA clones for KIR103 have been isolated and are shown to be formed by alternative mRNA splicing with exon skipping. Some of these truncated KIR103 cDNA could encode shorter transmembrane molecules, whereas others lack the transmembrane domain and are candidate genes for secreted KIR products. KIR103 is localized to the KIR genetic region on chromosome 19q13.4.