Placental site trophoblastic tumor (PSTT): a case report and review of the literature

Placental site trophoblastic tumor (PSTT), also known as atypical choriocarcinoma, syncytioma, chorioepitheliosis or trophoblastic pseudotumor, is a rare gestational trophoblastic disease (0.25-5% of all trophoblastic tumors) and it is composed by neoplastic proliferation of intermediate trophoblasts at placental implantation site. It consists of aggregates or sheets of large, polyhedral to round, predominantly mononucleated cells with a characteristic vascular and myometrial invasion. Main differential diagnoses are gestational choriocarcinoma (GC) and epitelioid trophoblastic tumor (ETT). We present a case of PSTT in a 25-year-old woman. Neoplastic cells showed moderate/high nuclear pleomorphism, abundant amphophilic, eosinophilic and clear cytoplasm, numerous mitotic figures (10 mitoses/10 HPF), and myometrial invasion. Other features are necrosis, vascular invasion with replacement of myometrial vessels by tumor cells and hemorrhage. The patient showed typical low serum β-hCG levels and high serum humane placental lactogen (hPL) levels.

Clinically Relevant Molecular Subtypes in Leiomyosarcoma

PURPOSE

Leiomyosarcoma is a malignant neoplasm with smooth muscle differentiation. Little is known about its molecular heterogeneity and no targeted therapy currently exists for leiomyosarcoma. Recognition of different molecular subtypes is necessary to evaluate novel therapeutic options. In a previous study on 51 leiomyosarcomas, we identified three molecular subtypes in leiomyosarcoma. The current study was performed to determine whether the existence of these subtypes could be confirmed in independent cohorts.

EXPERIMENTAL DESIGN

Ninety-nine cases of leiomyosarcoma were expression profiled with 3'end RNA-Sequencing (3SEQ). Consensus clustering was conducted to determine the optimal number of subtypes.

RESULTS

We identified 3 leiomyosarcoma molecular subtypes and confirmed this finding by analyzing publically available data on 82 leiomyosarcoma from The Cancer Genome Atlas (TCGA). We identified two new formalin-fixed, paraffin-embedded tissue-compatible diagnostic immunohistochemical markers; LMOD1 for subtype I leiomyosarcoma and ARL4C for subtype II leiomyosarcoma. A leiomyosarcoma tissue microarray with known clinical outcome was used to show that subtype I leiomyosarcoma is associated with good outcome in extrauterine leiomyosarcoma while subtype II leiomyosarcoma is associated with poor prognosis in both uterine and extrauterine leiomyosarcoma. The leiomyosarcoma subtypes showed significant differences in expression levels for genes for which novel targeted therapies are being developed, suggesting that leiomyosarcoma subtypes may respond differentially to these targeted therapies.

CONCLUSIONS

We confirm the existence of 3 molecular subtypes in leiomyosarcoma using two independent datasets and show that the different molecular subtypes are associated with distinct clinical outcomes. The findings offer an opportunity for treating leiomyosarcoma in a subtype-specific targeted approach.

Probiotics for human lactational mastitis

The use of culture-dependent and -independent techniques to study the human milk microbiota and microbiome has revealed a complex ecosystem with a much greater diversity than previously anticipated. The potential role of the milk microbiome appears to have implications not only for short- and long-term infant health but also for mammary health. In fact, mammary disbiosis, which may be triggered by a variety of host, microbial and medical factors, often leads to acute, subacute or subclinical mastitis, a condition that represents the first medical cause for undesired weaning. Multiresistance to antibiotics, together with formation of biofilms and mechanisms for evasion of the host immune response, is a common feature among the bacterial agents involved. This explains why this condition uses to be elusive to antibiotic therapy and why the development of new strategies for mastitis management based on probiotics is particularly appealing. In fact, selected lactobacilli strains isolated from breast milk have already shown a high efficacy for treatment.

CDC42-positive macrophages may prevent malignant transformation of ovarian endometriosis

It is currently thought that most clear cell and endometrioid carcinomas arise from ovarian endometriosis. We recently suggested that, besides their origin in the ovary, reduction of CDC42 messenger RNA (a member of the RHO GTPase family) may contribute to explain why clear cell carcinomas are not uncommonly found limited to the ovary (stage I). On the other hand, little is known about the expression of CDC42 in ovarian endometriosis with and without carcinoma. Twenty-two endometriotic cysts not associated with carcinoma, 19 endometriotic cysts associated with carcinoma (contiguous endometriosis), as well as the 19 corresponding tumors (11 clear cell, 4 endometrioid, and 4 mixed-clear cell and endometrioid-carcinomas) were investigated. We analyzed CDC42 expression both by real-time polymerase chain reaction and immunohistochemistry. Endometriotic cysts not associated with carcinoma showed higher expression of CDC42 messenger RNA than cysts associated with carcinoma (P = .002). Immunohistochemically, CDC42 was exclusively expressed by macrophages. CDC42-positive macrophages were present in most of the endometriotic cysts not associated with carcinoma (11/19, or 58%). In contrast, only 5 endometriotic cysts containing carcinoma (contiguous endometriosis) (5/18, or 28%) and 1 ovarian carcinoma arising from endometriosis (1/18, or 5%) had CDC42-positive macrophages (58% versus 28%, P = .065; 28% versus 5%, P = .046). Our results raise the possibility that CDC42-positive macrophages may prevent the development of endometrioid and clear cell carcinomas.

Gene expression analysis identifies two groups of ovarian high-grade serous carcinomas with different prognosis

Gene expression profiling is an important tool to evaluate genetic heterogeneity in carcinomas and is useful to develop expression-based classifications for many types of cancer, as well as markers of disease outcome. In this study, we have investigated the expression profile of 22 genes involved in the PI3K-AKT pathway in 26 high-grade ovarian carcinomas (19 serous and 7 clear cell carcinomas). Unsupervised hierarchical clustering divided high-grade ovarian carcinomas into three groups. Although all clear cell carcinomas clustered in one group, high-grade serous carcinomas were segregated into two separate groups with different prognosis (P=0.05). High expression of CASP3, XIAP (X-linked inhibitor of apoptosis) , NFKB1, FAS, and GSK3B mRNAs identified high-grade serous carcinomas with better prognosis. In multivariate analysis, these cluster groups were of prognostic significance independent of age, tumor size, and tumor stage (P=0.008). To validate the mRNA expression data, we studied the immunohistochemical expression of caspase-3 and XIAP on a tissue microarray. Immunoreaction for caspase-3 was concordant with the results obtained by mRNA expression analysis (Spearman r=0.762, P=0.000). Caspase-3 was exclusively expressed by the macrophages. Furthermore, co-expression of caspase-3 and XIAP identified high-grade serous carcinomas with different prognosis (P=0.03). Our results suggest that there are different biological subtypes of high-grade serous carcinomas.

Variations in stromal signatures in breast and colorectal cancer metastases

The tumour microenvironment (TME) plays an important role in tumour survival and growth, but little is known about the degree of preservation between different stromal response patterns found in primary tumours and their metastases. We have previously identified gene expression profiles for two distinct stromal signatures in breast carcinoma of fibroblast (aka DTF) and macrophage (aka CSF1) response and found them to be correlated with clinicopathological features, including outcome. In this study, we compare the DTF fibroblast and CSF1 macrophage stromal response patterns in primary breast and colorectal cancers to their matched lymph node metastases. In both breast and colorectal cancer, there was a significant positive correlation between the CSF1 macrophage signature in the primary tumours and the matched lymph node metastases, as assessed by immunohistochemical markers. No such correlation was observed for the DTF fibroblast signature. A similar result was seen in independent analysis of two published gene expression microarray datasets. The variations of these stromal reaction patterns from the primary to the metastasis shed light on the relationship between the neoplastic cells and the non-neoplastic cells in the TME. The preservation of the CSF1 macrophage response pattern in metastases lends support to targeting the CSF1 pathway in cancer.

Discovery of molecular subtypes in leiomyosarcoma through integrative molecular profiling

Leiomyosarcoma (LMS) is a soft tissue tumor with a significant degree of morphologic and molecular heterogeneity. We used integrative molecular profiling to discover and characterize molecular subtypes of LMS. Gene expression profiling was performed on 51 LMS samples. Unsupervised clustering showed three reproducible LMS clusters. Array comparative genomic hybridization (aCGH) was performed on 20 LMS samples and showed that the molecular subtypes defined by gene expression showed distinct genomic changes. Tumors from the 'muscle-enriched' cluster showed significantly increased copy number changes (P=0.04). A majority of the muscle-enriched cases showed loss at 16q24, which contains Fanconi anemia, complementation group A, known to have an important role in DNA repair, and loss at 1p36, which contains PRDM16, of which loss promotes muscle differentiation. Immunohistochemistry (IHC) was performed on LMS tissue microarrays (n=377) for five markers with high levels of messenger RNA in the muscle-enriched cluster (ACTG2, CASQ2, SLMAP, CFL2 and MYLK) and showed significantly correlated expression of the five proteins (all pairwise P<0.005). Expression of the five markers was associated with improved disease-specific survival in a multivariate Cox regression analysis (P<0.04). In this analysis that combined gene expression profiling, aCGH and IHC, we characterized distinct molecular LMS subtypes, provided insight into their pathogenesis, and identified prognostic biomarkers.

Circulating tumour cells demonstrate an altered response to hypoxia and an aggressive phenotype

Background:

Tumours contain hypoxic regions that select for an aggressive cell phenotype; tumour hypoxia induces metastasis-associated genes. Treatment refractory patients with metastatic cancer show increased numbers of circulating tumour cells (CTCs), which are also associated with disease progression. The aim of this study was to examine the as yet unknown relationship between hypoxia and CTCs.

Methods:

We generated human MDA-MB-231 orthotopic xenografts and, using a new technology, isolated viable human CTCs from murine blood. The CTCs and parental MDA-MB-231 cells were incubated at 21 and 0.2% (hypoxia) oxygen, respectively. Colony formation was assayed and levels of hypoxia- and anoxia-inducible factors were measured. Xenografts generated from CTCs and parental cells were compared.

Results:

MDA-MB-231 xenografts used to generate CTCs were hypoxic, expressing hypoxia factors: hypoxia-inducible factor1 alpha (HIF1α) and glucose transporter protein type 1 (GLUT1), and anoxia-induced factors: activating transcription factor 3 and 4 (ATF3 and ATF4). Parental MDA-MB-231 cells induced ATF3 in hypoxia, whereas CTCs expressed it constitutively. Asparagine synthetase (ASNS) expression was also higher in CTCs. Hypoxia induced ATF4 and the HIF1α target gene apelin in CTCs, but not in parental cells. Hypoxia induced lower levels of carbonic anhydrase IX (CAIX), GLUT1 and BCL2/adenovirus E1B 19-KD protein-interacting protein 3 (BNIP3) proteins in CTCs than in parental cells, supporting an altered hypoxia response. In chronic hypoxia, CTCs demonstrated greater colony formation than parental cells. Xenografts generated from CTCs were larger and heavier, and metastasised faster than MDA-MB-231 xenografts.

Conclusion:

CTCs show an altered hypoxia response and an enhanced aggressive phenotype in vitro and in vivo.

A panel of antibodies to determine site of origin and malignancy in smooth muscle tumors

Leiomyosarcomas are malignant smooth muscle tumors that occur most commonly in the gynecologic tract and soft tissue. There are different diagnostic criteria of malignancy for smooth muscle tumors arising at gynecologic and soft tissue sites and they may be managed differently but determining the primary site of a smooth muscle tumor can be difficult in some cases. In addition, the distinction between malignant and benign gynecologic tract smooth muscle tumors on morphologic grounds can be challenging. Using a series of tissue microarrays that contain 245 cases of leiomyosarcomas (102 gynecologic) with survival data, and 49 cases of uterine leiomyoma, we examined the ability of selected immune-markers (estrogen receptor (ER) and WT1) to distinguish between leiomyosarcomas of gynecologic and nongynecologic origin. In addition, we examined whether immunostains for p16, p53 and Ki-67 could distinguish between malignant and benign gynecologic smooth muscle tumors. ER nuclear positivity was observed in 3 and 50% of the nongynecologic and gynecologic leiomyosarcomas, respectively (P<0.001). Nuclear WT1 positivity was seen in 0 and 8% of the nongynecologic and gynecologic leiomyosarcomas, respectively (P<0.001). 87% of primary gynecologic leiomyosarcomas and 2% of uterine leiomyomas showed diffuse (>or=50% of cells) p16 staining (P<0.001). 23% of gynecologic leiomyosarcomas showed p53 immunopositivity (>or=50% of cells) whereas none of the leiomyomas were positive for p53 (P<0.001). 65% of the gynecologic leiomyosarcomas and 0% of the leiomyomas exhibited >10% Ki-67 proliferation index (P<0.001). Diffuse p16 and p53 immunopositivity and high Ki-67 proliferation index, singly or in combination, yielded an overall sensitivity of 92% and specificity of 98% for distinguishing between gynecologic leiomyosarcomas and leiomyomas and can be used as indicators of malignancy for gynecologic smooth muscle tumors. Although ER positivity can be used to support the gynecologic origin of a leiomyosarcomas, nuclear WT1 immunostaining is of little use.

MicroRNA profiling of BRCA1/2 mutation-carrying and non-mutation-carrying high-grade serous carcinomas of ovary

BACKGROUND

MicroRNAs (miRNA) are 20 approximately 25 nucleotide non-coding RNAs that inhibit the translation of targeted mRNA, and they have been implicated in the development of human malignancies. High grade serous ovarian carcinomas, the most common and lethal subtype of ovarian cancer, can occur sporadically or in the setting of BRCA1/2 syndromes. Little is known regarding the miRNA expression profiles of high grade serous carcinoma in relation to BRCA1/2 status, and compared to normal tubal epithelium, the putative tissue of origin for high grade serous carcinomas.

METHODOLOGY/PRINCIPAL FINDINGS

Global miRNA expression profiling was performed on a series of 33 high grade serous carcinomas, characterized with respect to BRCA1/2 status (mutation, epigenetic silencing with loss of expression or normal), and with clinical follow-up, together with 2 low grade serous carcinomas, 2 serous borderline tumors, and 3 normal fallopian tube samples, using miRNA microarrays (328 human miRNA). Unsupervised hierarchical clustering based on miRNA expression profiles showed no clear separation between the groups of carcinomas with different BRCA1/2 status. There were relatively few miRNAs that were differentially expressed between the genotypic subgroups. Comparison of 33 high grade serous carcinomas to 3 normal fallopian tube samples identified several dysregulated miRNAs (false discovery rate <5%), including miR-422b and miR-34c. Quantitative RT-PCR analysis performed on selected miRNAs confirmed the pattern of differential expression shown by microarray analysis. Prognostically, lower level miR-422b and miR-34c in high grade serous carcinomas were both associated with decreased disease-specific survival by Kaplan-Meier analysis (p<0.05).

CONCLUSIONS/SIGNIFICANCE

High grade serous ovarian carcinomas with and without BRCA1/2 abnormalities demonstrate very similar miRNA expression profiles. High grade serous carcinomas as a group exhibit significant miRNA dysregulation in comparison to tubal epithelium and the levels of miR-34c and miR-422b appear to be prognostically important.

The macrophage colony-stimulating factor 1 response signature in breast carcinoma

PURPOSE

Macrophages play an important role in breast carcinogenesis. The pathways that mediate the macrophage contribution to breast cancer and the heterogeneity that exists within macrophages are incompletely understood. Macrophage colony-stimulating factor 1 (CSF1) is the primary regulator of tissue macrophages. The purpose of this study was to define a novel CSF1 response signature and to evaluate its clinical and biological significance in breast cancer.

EXPERIMENTAL DESIGN

We defined the CSF1 response signature by identifying genes overexpressed in tenosynovial giant cell tumor and pigmented villonodular synovitis (tumors composed predominantly of macrophages recruited in response to the overexpression of CSF1) compared with desmoid-type fibromatosis and solitary fibrous tumor. To characterize the CSF1 response signature in breast cancer, we analyzed the expression of CSF1 response signature genes in eight published breast cancer gene expression data sets (n = 982) and did immunohistochemistry and in situ hybridization for CSF1 response genes on a breast cancer tissue microarray (n = 283).

RESULTS

In both the gene microarray and tissue microarray analyses, a consistent subset (17-25%) of breast cancers shows the CSF1 response signature. The signature is associated with higher tumor grade, decreased expression of estrogen receptor, decreased expression of progesterone receptor, and increased TP53 mutations (P < 0.001).

CONCLUSIONS

Our data show that the CSF1 response signature is consistently seen in a subset of breast carcinomas and correlates with biological features of the tumor. Our findings provide insight into macrophage biology and may facilitate the development of personalized therapy for patients most likely to benefit from CSF1-targeted treatments.

Ror2, a developmentally regulated kinase, promotes tumor growth potential in renal cell carcinoma

Inappropriate kinase expression and subsequent promiscuous activity defines the transformation of many solid tumors including renal cell carcinoma (RCC). Thus, the expression of novel tumor-associated kinases has the potential to dramatically shape tumor cell behavior. Further, identifying tumor-associated kinases can lend insight into patterns of tumor growth and characteristics. Here, we report the identification of the RTK-like orphan receptor 2 (Ror2), a new tumor-associated kinase in RCC cell lines and primary tumors. Ror2 is an orphan receptor tyrosine kinase with physiological expression normally seen in the embryonic kidney. However, in RCC, Ror2 expression correlated with expression of genes involved at the extracellular matrix, including Twist and matrix metalloprotease-2 (MMP2). Expression of MMP2 in RCC cells was suppressed by Ror2 knockdown, placing Ror2 as a mediator of MMP2 regulation in RCC and a potential regulator of extracellular matrix remodeling. The suppression of Ror2 not only inhibited cell migration, but also inhibited anchorage-independent growth in soft agar and growth in an orthotopic xenograft model. These findings suggest a novel pathway of tumor-promoting activity by Ror2 within a subset of renal carcinomas, with significant implications for unraveling the tumorigenesis of RCC.

Coordinate expression of colony-stimulating factor-1 and colony-stimulating factor-1-related proteins is associated with poor prognosis in gynecological and nongynecological leiomyosarcoma

Previously, we showed that the presence of high numbers of macrophages correlates with poor prognosis in nongynecological leiomyosarcoma (LMS). In gynecological LMS, a similar trend was noted but did not reach statistical significance. Colony-stimulating factor-1 (CSF1) is a major chemoattractant for macrophages. Here we show that in a subset of LMS cases, CSF1 is expressed by the malignant cells. Previously, we found that CSF1 is translocated and highly expressed in tenosynovial giant cell tumors (TGCTs), and this observation allowed us to identify genes that showed a coordinate expression with CSF1. Here, we evaluated the expression of CSF1 and TGCT-associated proteins in 149 cases of LMS. The coordinate expression of CSF1 and three TGCT-associated proteins (CD163, FCGR3a, and CTSL1) identified cases with poor prognosis in both gynecological LMS (P = 0.00006) and nongynecological LMS (P = 0.03). In gynecological LMS, the coordinate expression of these four markers was the only independent prognosticator in multivariate analysis (hazard ratio, 4.2; 95% CI, 1.12 to 16; P = 0.03). Our findings indicate that CSF1 may play an important role in the clinical behavior of LMS that may open a window for new therapeutic reagents.

Activation of the NF-kappaB signalling pathway in diffuse large B-cell lymphoma: clinical implications

AIM

To characterize the activation of the nuclear factor (NF)-kappaB pathway in diffuse large B-cell lymphoma (DLBCL) by immunohistochemistry.

METHODS AND RESULTS

Sixty-six DLBCLs treated with anthracycline-containing chemotherapy were evaluated with antibodies against phosphorylated p65 (P-p65), p65, p50, p52, IKK alpha, and phosphorylated I kappaB (P-I kappaB). NF-kappaB activation was based on the expression of P-p65, P-I kappaB, and nuclear expression of p65 or p52 in the tumour cells. P-p65 and P-I kappaB were expressed in 13 (20%) and 17 cases (26%), respectively. p65, p52 and IKK alpha were found in the cytoplasm. A correlation was found between expression of P-p65 and P-I kappaB (P < 0.0001), but not between the two subtypes of DLBCL [germinal centre B cell and non-germinal centre (GC)]. P-p65+ tumours showed a better response to chemotherapy (P = 0.025) and a trend to increased event-free survival (P = 0.08). However, P-I kappaB expression was not associated with either clinical response or survival. Bcl-2 was not preferentially expressed on DLBCL tumours with NF-kappaB activation, as determined by expression of P-p65 and P-I kappaB proteins.

CONCLUSIONS

NF-kappaB activation in DLBCL is preferentially mediated through the classical pathway and a novel mechanism involving phosphorylation of p65. Activation of NF-kappaB by P-p65 is associated with good prognosis. NF-kappaB activation is not confined to non-GC DLBCL exclusively.

Prognostic significance of macrophage infiltration in leiomyosarcomas

PURPOSE

Macrophages are migratory cells that are frequently recruited to the site of tumors. Their presence is associated with poor clinical outcome in a variety of epithelial malignancies. The aim of this study is to examine the prognostic significance of tumor-associated macrophages in sarcomas.

EXPERIMENTAL DESIGN

Global gene expression profiling data of a series of soft tissue tumors were analyzed for macrophage-associated gene expression. Immunohistochemistry on tissue microarrays containing leiomyosarcoma cases with known clinical outcome was used to verify the presence of macrophages and to examine the relationship between tumor-associated macrophages and clinical outcome.

RESULTS

Gene expression profiling revealed high-level expression of several macrophage-associated genes such as CD163 and CD68 in a subset of leiomyosarcomas, indicating the presence of variable numbers of tumor-infiltrating macrophages. This was confirmed by CD68 and CD163 immunostaining of a tissue microarray containing 149 primary leiomyosarcomas. Kaplan-Meier survival analysis showed that high density of tumor-infiltrating macrophages as identified by CD163 or CD68 staining is associated with a significantly worse disease-specific survival in nongynecologic leiomyosarcomas, whereas leiomyosarcomas arising from the gynecologic tract showed no significant association between macrophage infiltration and survival. The presence of tumor necrosis did not correlate significantly with outcome.

CONCLUSIONS

An increased density of CD163- or CD68-positive tumor-infiltrating macrophages is associated with poor outcome in nongynecologic leiomyosarcomas. This may help the clinical management of patients with leiomyosarcomas.

Abstract 4998: Molecular profiling reveals heterogeneity of active self-renewal pathways in bladder cancer stem cells

The objective of the current study is to investigate the functional involvement of self-renewal related genes in patient bladder cancer stem cells. First, by fractionating primary patient bladder transitional cell carcinomas (TCCs) into subpopulations with flow cytometry, a unique tumor-initiating subpopulation expressing CD44 was identified in 5 independent TCCs, based on their enriched potential (10-200 folds) to induce xenograft tumors in immunocompromised mice. To extend this finding to a larger sample set, we analyzed a tissue array containing more than 300 bladder TCCs by immunohistochemistry. Approximately 40.4% of TCCs contain CD44+ cells; these cells usually express cytokeratin 5 (CK5) (P&lt;0.0001) but not cytokeratin 20 (P=0.8160). In addition, cellular morphologies of CD44+ tumor cells are often small and round shape. These data suggest that CD44+ tumor cells retain cytokeratin markers and cellular morphologies resembling that of urothelial basal cells. Further, molecular profiling of oncogenic proteins implicated in the self-renewal of stem cells (i.e. Bmi1, Stat3, ß-catenin, Gli1, Oct4 and Nanog) revealed heterogeneity in bladder TCCs. Different subsets of CD44+ bladder TCCs express either one or more of different self-renewal proteins in their active forms (i.e. ~10% with nuclear Bmi1, 30% with nuclear Stat3, 5% with nuclear ß-catenin, 85% with active Gli1 and 0% with active Oct4 nor Nanog). In particular, in situ hybridization demonstrated that Gli1 mRNA was present in over 85% of bladder TCC specimens analyzed. Therefore, we examined the functional significance of the sonic hedgehog pathway in bladder tumor development. In patient bladder xenografts that originally contained active Gli1 in the cancer stem cells, preliminary experiment demonstrated that inhibition of this pathway with cyclopamine resulted in partial reduction of tumor volume (4 out of 6 xenografts). Previous reports demonstrated that genetic mutations in the pathway components (i.e. PTCH or Gli1) leading to constitutive Gli1 activation is rare in bladder TCCs. Preliminary microRNA (miRs) profiling of CD44+ bladder cancer stem cells using a real-time PCR based approach revealed a panel of differentially expressed miRs. Interestingly, in several highly elevated miRs in CD44+ bladder cancer stem cells, the negative regulators of the Gli1 pathways (i.e. PTCH and SUFU) are among the top predicted targets for these miRs. Further experiments are ongoing to validate the possible involvement of miRs in regulating the Gli1 pathways in bladder cancer stem cells. In conclusion, we demonstrated the existence of a functionally unique, CD44+ tumorigenic subpopulation in a subset of bladder TCCs. Diverse “self-renewal” proteins, including Gli1, possibly contribute to the tumorigenic properties of cancer stem cells in different subset of patient bladder TCCs.

[A case of cutaneous extramedullary hematopoiesis associated with idiopathic myelofibrosis]

Cutaneous extramedullary hematopoiesis is a rare manifestation of chronic myeloproliferative processes, mainly chronic idiopathic myelofibrosis. In adults, it manifests as macules, papules, nodules, and ulcers on the trunk. The lesions usually appear soon after diagnosis and the possibility of a relationship between splenectomy and the appearance of extramedullary foci of hematopoiesis is still debated. Diagnosis is based on histopathology showing an infiltrate with different combinations of myeloid and erythroid cell precursors and megakaryocytes. Symptomatic treatment is provided alongside treatment of the underlying disease. We report a new case associated with chronic idiopathic myelofibrosis in which foci of cutaneous extramedullary hematopoiesis were observed 9 years after initial diagnosis. The lesions were progressive and the patient went on to develop acute myeloid leukemia.

MicroRNA expression signature of human sarcomas

MicroRNAs (miRNAs) are approximately 22 nucleotide-long noncoding RNAs involved in several biological processes including development, differentiation and proliferation. Recent studies suggest that knowledge of miRNA expression patterns in cancer may have substantial value for diagnostic and prognostic determinations as well as for eventual therapeutic intervention. We performed comprehensive analysis of miRNA expression profiles of 27 sarcomas, 5 normal smooth muscle and 2 normal skeletal muscle tissues using microarray technology and/or small RNA cloning approaches. The miRNA expression profiles are distinct among the tumor types as demonstrated by an unsupervised hierarchical clustering, and unique miRNA expression signatures were identified in each tumor class. Remarkably, the miRNA expression patterns suggested that two of the sarcomas had been misdiagnosed and this was confirmed by reevaluation of the tumors using histopathologic and molecular analyses. Using the cloning approach, we also identified 31 novel miRNAs or other small RNA effectors in the sarcomas and normal skeletal muscle tissues examined. Our data show that different histological types of sarcoma have distinct miRNA expression patterns, reflecting the apparent lineage and differentiation status of the tumors. The identification of unique miRNA signatures in each tumor type may indicate their role in tumorigenesis and may aid in diagnosis of soft tissue sarcomas.

Annotation and query of tissue microarray data using the NCI Thesaurus

Background

The Stanford Tissue Microarray Database (TMAD) is a repository of data serving a consortium of pathologists and biomedical researchers. The tissue samples in TMAD are annotated with multiple free-text fields, specifying the pathological diagnoses for each sample. These text annotations are not structured according to any ontology, making future integration of this resource with other biological and clinical data difficult.

Results

We developed methods to map these annotations to the NCI thesaurus. Using the NCI-T we can effectively represent annotations for about 86% of the samples. We demonstrate how this mapping enables ontology driven integration and querying of tissue microarray data. We have deployed the mapping and ontology driven querying tools at the TMAD site for general use.

Conclusion

We have demonstrated that we can effectively map the diagnosis-related terms describing a sample in TMAD to the NCI-T. The NCI thesaurus terms have a wide coverage and provide terms for about 86% of the samples. In our opinion the NCI thesaurus can facilitate integration of this resource with other biological data.

Clinical utility of bone marrow flow cytometry in B-cell non-Hodgkin lymphomas (B-NHL)

AIM

To determine the efficacy of flow cytometry (FC) in the assessment of bone marrow (BM) in B-cell non-Hodgkin lymphoma (B-NHL). FC is a common practice, but is far from being validated.

METHODS AND RESULTS

Morphological analysis and FC immunophenotyping were performed on 421 samples. T-cell lymphomas, Hodgkin's disease, chronic lymphocytic leukaemia and hairy cell leukaemia were not included in the study. Clonality was assessed by the standard kappa/lambda/CD19 test. Aberrant immunophenotypes present in the B-cell subpopulation were also investigated. A double-step procedure was employed in all cases to increase the sensitivity of the FC procedure. Of 380 evaluable samples, 188 corresponded to follicular lymphoma (FL), 58 to diffuse large B-cell lymphoma (DLBCL), 57 to mantle cell lymphoma (MCL), seven to Burkitt's lymphoma and the remaining 70 samples to other low-grade lymphomas. Morphological marrow infiltration was found in 148 cases, and flow immunophenotyping identified 138 cases with BM involvement. A concordance between the two methods was detected in 298 cases (79%). There was a discordance in 82 cases (21%): morphology positive/FC negative in 46 cases and morphology negative/FC positive in 36 (61% of all cases with discordance were from FL). There was no difference in outcome when patients with discordances were compared with patients without discordances.

CONCLUSIONS

Most samples showed concordance between morphological and FC results. FC identified BM involvement in the absence of morphological infiltration. Morphology/FC discordance seems to have no influence on the outcome of FL patients.

Insertion of the CCND1 gene into the IgH locus in a case of leukaemic small cell mantle lymphoma with normal chromosomes 11 and 14

The t(11;14)(q13;q32) translocation is considered to be the cytogenetic hallmark of mantle cell lymphoma. This report describes a case of leukaemic mantle cell lymphoma in which conventional cytogenetics on stimulated peripheral blood cells showed a 46,XY, t(1;12)(p21;q23)/46,XY karyotype. Fluorescence in situ hybridisation analysis using a dual colour immunoglobulin heavy chain (IgH)/CCND1 probe showed a fusion hybridisation signal on one normal chromosome 14, indicating that an insertion of the CCND1 gene into the 14q32/IgH locus had taken place. Overexpression of the cyclin D1 protein was demonstrated on bone marrow trephine by immunohistochemical staining.

VP5, the nonstructural polypeptide of infectious bursal disease virus, accumulates within the host plasma membrane and induces cell lysis

Infectious bursal disease virus (IBDV) encodes a 17-kDa nonstructural polypeptide known as VP5. This polypeptide is not essential for virus replication in vitro but it plays an important role in in vivo dissemination and pathogenesis. We have characterized the expression of VP5 in three eukaryotic systems: (i) IBDV-infected chicken embryo fibroblasts; (ii) BSC-1 cells infected with a recombinant vaccinia virus vector; and (iii) Cos-1 cells transiently transfected with a plasmid vector. Immunofluorescence analyses showed that upon expression VP5 accumulates within the plasma membrane. This finding was consistent with sequence-based topology predictions, indicating that VP5 is a class II membrane protein with a cytoplasmic N-terminus and an extracellular C-terminal domain. Brefeldin A treatment of VP5-expressing cells prevented the accumulation of this polypeptide in the plasma membrane, thus showing the requirement of an active exocytic pathway to reach that compartment. Expression of VP5 was shown to be highly cytotoxic. Induction of VP5 expression resulted in the alteration of cell morphology, the disruption of the plasma membrane, and a drastic reduction of cell viability. VP5-induced cytotoxicity was prevented by blocking its transport to the membrane with Brefeldin A. Our findings suggest that VP5 plays an important role in the release of the IBDV progeny.

[The production of a latex immunoglobulin conjugate for the diagnosis of Gardnerella vaginalis]

To obtain an anti-Gadnerella vaginalis latex globulin, specific immunosera to reference strain (ATCC 14018) and to a clinical isolation strain pool were produced. These immunosera were characterized using PAGE-SDS and immunoblotting where a close antigenic relation between the clinical isolation strains and the reference strain was observed. The latex globulin conjugates obtained from these 2 immunosera were evaluated in vitro with a resulting level of detection of 10 ufc/mL of Gardnerella vaginalis. These two conjugates were also evaluated in clinical samples and compared with the 6 vaginalis culture and the criteria considered for diagnosing bacterial vaginosis. The anti-strain pool (II) latex globulin conjugate turned out to be more sensitive and specific than anti-G. vaginalis ATCC strain (I) latex globulin.

PCR analysis in the pathological diagnosis of Whipple's disease: emphasis on extraintestinal involvement or atypical morphological features

PCR analysis of species-specific bacterial 16S rRNA gene of Tropheryma whippelii was performed in biopsies from 10 cases of Whipple's disease (WD). In seven patients showing the typical clinical picture of WD, PCR was performed on the diagnostic intestinal biopsy. In the remaining three cases (an autopsy case of disseminated WD and two patients showing lymphadenopathy as the initial clinical presentation), PCR was done on lymph node specimens. In one of the lymph node biopsies, an unusual sarcoidlike granulomatous reaction had led to the diagnosis of sarcoidosis. The specific bacterial DNA was detected in all cases, both in intestinal biopsies and in lymph node specimens. Follow-up biopsies after antibiotic therapy were evaluated in two patients. The two follow-up biopsies were negative, although in both of them scattered nests of PAS-positive macrophages remained. The results of this study suggest that PCR analysis of species-specific sequences of the 16S rRNA of Tropheryma whippelii is a very useful tool for the pathological diagnosis of WD. It confirms the diagnosis of WD in intestinal biopsies as well as in extraintestinal sites, even when the morphological appearance is not typical. It is also the most precise technique for monitoring therapeutic effects.

Interruption of the aortic arch in adults

The interruption of the aortic arch is a rare cardiac congenital disease; such patients may occasionally survive to adulthood without surgery. The associated intracardiac malformations may modify survival. Our aim is to report three young adults (18-19 years of age) with interruption of the aortic arch. Two had type C, and the other had type B with subpulmonic ventricular septal defect and pulmonary valve insufficiency. We review 106 cases collected from the medical literature into 3 groups: 1) the whole group of patients; 2) patients with isolated interruption of the aortic arch, and 3) patients with interruption of the aortic arch associated with ventricular septal defect. In the whole group we found 18 cases of interruption of the aortic arch type A, and 25 cases of interruption of the aortic arch type B; 37 cases of isolated interruption of the aortic arch and 43 cases associated with ventricular septal defect. Fifty percent of the patients died before 15 days of life (0.042 years). According to the cumulative frequency graphic, only 5% of the patients survived beyond the age of 5 years. We found no information to relate patient's survival rate and anatomic type of the interruption of the aortic arch. From adolescence, the survival of the patients with interruption of the aortic arch associated to septal ventricular defect was 7%, and a 14% survival was found in patients with isolated interruption of the aortic arch. No statistical difference was found between the means of the ages of these two groups (P > 0.25).