MDM2 dual-color in situ hybridization (DISH) aids the diagnosis of intimal sarcomas.

Intimal sarcoma is a rare malignant mesenchymal tumor arising from the intima of the great vessels and the heart, and is associated with poor outcomes. As clinico-radiological findings and pathological features are often non-specific, the diagnosis of intimal sarcoma is challenging. Recently, MDM2 amplification was reported to be a characteristic genetic event in this tumor. In the present study, we examined MDM2 status by immunohistochemistry, and by fluorescence and dual-color in situ hybridization (FISH and DISH) using intimal sarcoma (10 tumors), angiosarcoma (5), pulmonary sarcomatoid carcinoma (p-SC) (14) and chronic pulmonary thrombosis (CPT) (3) to investigate MDM2 amplification for the diagnosis of intimal sarcoma. MDM2 and CDK4 were immunopositive in all 10 intimal sarcoma tumors, and high-level amplification of MDM2 was detected in eight tumors by both FISH and DISH. The other two tumors had polysomy of chromosome 12 and overexpression of p53 protein. Although MDM2 aberrations were observed in three p-SCs (two with amplification and one with polysomy), angiosarcomas and CPTs lacked MDM2 amplification. Furthermore, there was high concordance between FISH and DISH. In conclusion, we found that MDM2 amplification strongly supports the diagnosis of intimal sarcoma, and MDM2 DISH was a concordant method and an acceptable alternative to FISH. As MDM2 amplification and p53 overexpression were mutually exclusive, disruption of the MDM2-p53 pathway may be an essential genetic event for this malignant tumor.

Oral and Topical Sirolimus for Vascular Anomalies: A Multicentre Study and Review.

Vascular anomalies (VAs) may be associated with significant morbidity and mortality. The aim of this study was to evaluate the efficacy and safety of sirolimus (rapamycin) in the treatment of children and young adults with complicated VAs. A retrospective chart was created that included 19 patients treated with sirolimus for complicated VAs. Concurrently, a search of the PubMed database for VA cases treated with sirolimus was conducted. Descriptive analysis was performed and the efficiency rate of sirolimus was calculated. This retrospective study included 19 patients, 17 of whom were treated with oral sirolimus and 2 with topical sirolimus. Clinical improvement occurred in 15 patients (79%). One patient experienced near-complete resolution. Only 2 patients showed poor response and discontinued treatment. The literature review analysed 150 cases of VA treated with sirolimus. Sirolimus was efficient in 85% of cases, including 5 cases of complete resolution. Sirolimus appears to be an effective and safe treatment for children and young adults with complicated VAs.

Phosphoinositide 3-kinase: a new kid on the block in vascular anomalies.

Vascular anomalies are broadly divided into vascular tumours and malformations. These lesions are composed of abnormal vascular elements of various types, and mainly affect infants, children, and young adults. Vascular anomalies may be painful, may be complicated by bleeding, infection, or organ dysfunction, and can have secondary effects on other tissues. Current treatment strategies include surgical excision, pulsed laser, and sclerotherapy, which are invasive, with risks of recurrence. There are growing pharmacological options for these vascular anomalies, but, to date, no specific targeted therapies have been developed. Phosphoinositide 3-kinases (PI3Ks) constitute a family of lipid kinases that are involved in signal transduction and vesicular traffic, and that modulate important cellular processes such as proliferation, growth, and migration. Recent findings have indicated that the PI3K signalling pathway is important in the pathogenesis of vascular anomalies. This provides an opportunity to use PI3K inhibitors, which are in clinical trials for cancer treatment, for such lesions. Here, we provide an update on the classification of vascular anomalies, with their major features, and discuss the role of the PI3K signalling pathway in the pathogenesis of vascular anomalies, and their clinical implications and therapeutic opportunities. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

GNA14 Somatic Mutation Causes Congenital and Sporadic Vascular Tumors by MAPK Activation.

Vascular tumors are among the most common neoplasms in infants and children; 5%-10% of newborns present with or develop lesions within the first 3 months of life. Most are benign infantile hemangiomas that typically regress by 5 years of age; other vascular tumors include congenital tufted angiomas (TAs), kaposiform hemangioendotheliomas (KHEs), and childhood lobular capillary hemangiomas (LCHs). Some of these lesions can become locally invasive and unresponsive to pharmacologic intervention, leading to significant complications. Recent investigation has revealed that activating mutations in HRAS, KRAS, NRAS, GNAQ, and GNA11 can cause certain types of rare childhood vascular tumors, and we have now identified causal recurrent somatic activating mutations in GNA14 by whole-exome and targeted sequencing. We found somatic activating GNA14 c.614A>T (p.Gln205Leu) mutations in one KHE, one TA, and one LCH and a GNA11 c.547C>T (p.Arg183Cys) mutation in two LCH lesions. We examined mutation pathobiology via expression of mutant GNA14 or GNA11 in primary human endothelial cells and melanocytes. GNA14 and GNA11 mutations induced changes in cellular morphology and rendered cells growth-factor independent by upregulating the MAPK pathway. Our findings identify GNA14 mutations as a cause of childhood vascular tumors, offer insight into mechanisms of oncogenic transformation by mutations affecting Gaq family members, and identify potential targets for therapeutic intervention.

Efficacy and Safety of Mammalian Target of Rapamycin Inhibitors in Vascular Anomalies: A Systematic Review.

Mammalian target of rapamycin (mTOR) inhibitors are a promising new treatment in vascular anomalies, but no published randomized controlled trials are available. The aim of this systematic review of all reported cases was to assess the efficacy and safety of mTOR inhibitors in all vascular anomalies, except cancers, in children and adults. In November 2014 MEDLINE, CENTRAL, LILACS and EMBASE were searched for studies of mTOR inhibitors in any vascular condition, except for malignant lesions, in humans. Fourteen publications and 9 posters, with data on 25 and 59 patients, respectively, all < 18 years old were included. Of these patients, 35.7% (n = 30) had vascular tumours, and 64.3% (n = 54) had malformations. Sirolimus was the most frequent mTOR inhibitor used (98.8%, n = 83). It was efficient in all cases, at a median time of 2 weeks (95% confidence interval 1-10 weeks). Sirolimus was well tolerated, the main side-effect being mouth sores, which led to treatment withdrawal in one case. The dosage of sirolimus was heterogeneous, the most common being 1.6 mg/m2/day.

Akt1 and akt3 exert opposing roles in the regulation of vascular tumor growth.

Vascular tumors are endothelial cell neoplasms whose mechanisms of tumorigenesis are poorly understood. Moreover, current therapies, particularly those for malignant lesions, have little beneficial effect on clinical outcomes. In this study, we show that endothelial activation of the Akt1 kinase is sufficient to drive de novo tumor formation. Mechanistic investigations uncovered opposing functions for different Akt isoforms in this regulation, where Akt1 promotes and Akt3 inhibits vascular tumor growth. Akt3 exerted negative effects on tumor endothelial cell growth and migration by inhibiting activation of the translation regulatory kinase S6-Kinase (S6K) through modulation of Rictor expression. S6K in turn acted through a negative feedback loop to restrain Akt3 expression. Conversely, S6K signaling was increased in vascular tumor cells where Akt3 was silenced, and the growth of these tumor cells was inhibited by a novel S6K inhibitor. Overall, our findings offer a preclinical proof of concept for the therapeutic utility of treating vascular tumors, such as angiosarcomas, with S6K inhibitors.

Coactivated platelet-derived growth factor receptor {alpha} and epidermal growth factor receptor are potential therapeutic targets in intimal sarcoma.

Intimal sarcoma (IS) is a rare, malignant, and aggressive tumor that shows a relentless course with a concomitant low survival rate and for which no effective treatment is available. In this study, 21 cases of large arterial blood vessel IS were analyzed by immunohistochemistry and fluorescence in situ hybridization and selectively by karyotyping, array comparative genomic hybridization, sequencing, phospho-kinase antibody arrays, and Western immunoblotting in search for novel diagnostic markers and potential molecular therapeutic targets. Ex vivo immunoassays were applied to test the sensitivity of IS primary tumor cells to the receptor tyrosine kinase (RTK) inhibitors imatinib and dasatinib. We showed that amplification of platelet-derived growth factor receptor α (PDGFRA) is a common finding in IS, which should be considered as a molecular hallmark of this entity. This amplification is consistently associated with PDGFRA activation. Furthermore, the tumors reveal persistent activation of the epidermal growth factor receptor (EGFR), concurrent to PDGFRA activation. Activated PDGFRA and EGFR frequently coexist with amplification and overexpression of the MDM2 oncogene. Ex vivo immunoassays on primary IS cells from one case showed the potency of dasatinib to inhibit PDGFRA and downstream signaling pathways. Our findings provide a rationale for investigating therapies that target PDGFRA, EGFR, or MDM2 in IS. Given the clonal heterogeneity of this tumor type and the potential cross-talk between the PDGFRA and EGFR signaling pathways, targeting multiple RTKs and aberrant downstream effectors might be required to improve the therapeutic outcome for patients with this disease.

Intravascular lymphoma masquerading as Vogt-Koyanagi-Harada syndrome.

PURPOSE: To describe the clinical course of a case of intravascular lymphoma. DESIGN: Case report. METHODS: Retrospective chart review. RESULTS: A 56-year-old man presented with blurry vision associated with fever and decreased hearing. Ocular exam including fluorescein angiography and OCT was consistent with Vogt-Koyanagi-Harada syndrome and the patient initially improved with corticosteroids. Clinical deterioration led to further systemic workup and revealed intravascular lymphoma. The patient was started on chemotherapy with resolution of visual complaints. CONCLUSIONS: Intravascular lymphoma can present as a masquerade of VKH syndrome. Diagnosis can be aided with measurement of LDH and skin biopsy.

Leiomyosarcoma originating from the superior mesenteric vein: a case report and review of the literature.

We describe a rare case of leiomyosarcoma originating from the superior mesenteric vein with concomitant liver metastases in a 62-year-old woman. She underwent a tumor resection and venous reconstruction, right hemicolectomy, and right hepatic lobectomy. Since the tumor was weakly positive for c-kit, she was treated with imatinib mesylate for the recurrent liver tumors. She has survived for about 3 years after undergoing the surgical procedures.

Prostatic acid phosphatase is a possible tumor marker for intravascular large B-cell lymphoma.

Intravascular large B-cell lymphoma (LBCL) is a rare and aggressive subtype of diffuse LBCL characterized by disseminated intravascular proliferation of neoplastic lymphocytes. Obstruction of blood flow by tumor cells in a variety of organs can cause an array of clinical changes, including alteration of the neural and spinal system and the respiratory system, as well as skin lesions. It is usually very difficult to diagnose intravascular LBCL in a patient simply from clinical symptoms or laboratory examinations. We here document our findings that serum prostatic acid phosphatase levels in both males and a female (2.2-24.0 microg/L) reflect the presence of intravascular LBCL, changing synchronously in response to chemotherapy. To determine whether prostatic acid phosphatase (PAP) might be a useful tumor marker for early diagnosis, we reviewed five intravascular LBCLs. Immunohistochemically, tumor cells in all cases were positive for anti-PAP antibody. The results were further confirmed in one case by Western-blot analysis and in another by the detection of amplified messenger RNA for PAP in microdissected tumor cells, respectively. PAP has not been detected in 17 lymphomas (diffuse LBCL, 8 cases; follicular lymphoma, 3 cases; T-cell lymphoma, 3 cases; Hodgkin lymphoma, 3 cases) by Western blot analyses. We conclude that serum PAP is a useful tumor marker for intravascular LBCL and that it deserves further investigation in this context.

A 21-year-old woman with consumptive hypothyroidism due to a vascular tumor expressing type 3 iodothyronine deiodinase.

We present a 21-yr-old female with a large hepatic vascular tumor and subclinical hypothyroidism. A high level of the thyroid hormone inactivating enzyme type 3 iodothyronine deiodinase (D3) was detected in her tumor, and the TSH of 26.2 mU/liter returned to normal after surgical resection of the mass. This indicates that the vascular tumor caused this adult's hypothyroidism as has now been documented in nine infants with this syndrome. This first example of consumptive hypothyroidism in an adult indicates that the inactivation rate of thyroid hormone by D3 in a vascular tumor can stress the secretory capacity even of the TSH-stimulated normal adult thyroid gland.

Myeloperoxidase-positive intravascular large B-cell lymphoma.

Intravascular large B-cell lymphoma (IVLBL) is an uncommon form of non-Hodgkin lymphoma that is also known as malignant angioendotheliosis, intravascular lymphomatosis, and angiotropic large-cell lymphoma. The disease is characterized by a bizarre population of neoplastic cells, which are found systemically within vascular lumina. Although originally thought to be a neoplastic process of the endothelial cells, it has since been demonstrated, by molecular techniques and immunohistochemistry, that the neoplastic cells are of lymphoid origin. The differential diagnosis of these lesions includes granulocytic sarcomas that can be distinguished from IVLBL or other lymphomas by the presence of immunohistochemical positivity for myeloperoxidase. We describe a patient with a history of a myelodysplastic syndrome who subsequently developed IVLBL, which demonstrated immunohistochemical positivity for myeloperoxidase. To our knowledge, this represents the first case of a malignant lymphoma to demonstrate such findings.

Telomerase activity and lymphovascular invasion in breast cancer.

BACKGROUND: Telomerase is a ribonucleoprotein enzyme that plays an important role in cell immortalization and carcinogenesis. Lymphovascular invasion (LVI) is a fundamental step in the process of breast cancer metastasis and is recognized as an important prognostic factor in patients with breast cancer. METHODS: Using a PCR-based assay, telomerase activity was determined in 34 prospectively collected infiltrating breast carcinomas. Adjacent sections of the specimens were examined histologically by two experienced breast pathologists using light microscopy and haematoxylin & eosin staining. RESULTS: Telomerase activity was detected in 24 (71%) of 34 breast tumours. Two (20%) of 10 telomerase-negative tumours had LVI compared with 14 (58.3%) of 24 telomerase-positive tumours. This association was statistically significant (P<0.05). Telomerase activity was also significantly associated with nodal metastases but not with tumour grade, tumour size or menopausal status. CONCLUSIONS: Telomerase reactivation is significantly associated with LVI in breast cancer and may reflect the metastatic potential of the disease.

Measurement of telomerase activity in dog tumors.

Telomeres are specific structures present at the end of liner chromosomes. DNA polymerase can not synthesize the end of liner DNA and, as a result, the telomeres become progressively shortened by successive cell divisions. To overcome the end replication problem, telomerase adds new telomeric sequences to the end of chromosomal DNA. The enzyme activity is undetectable in most normal human adult somatic cells, in which shortening of the telomere is thought to limit the somatic-cell life span. In contrast to normal somatic cells, many human tumors possess telomerase activity. The present study looked at whether telomerase activity might serve as a marker for canine tumors. Telomerase activity was measured using the telomeric repeat amplification protocol assay. Normal dog somatic tissues showed little or no telomerase activity, while normal testis exhibited a high level of telomerase activity. We measured telomerase activity in tumor samples from 45 dogs; 21 mammary gland tumors, 16 tumors developed in the skin and oral cavity, 7 vascular tumors and 1 Sertoli cell tumor. Greater than 95% of the tumor samples contained telomerase activity (3-924 U/2 micrograms protein). The results obtained in this study indicated that telomerase should be a useful diagnostic marker for a variety of dog tumors, and it may serve as a target for antitumor chemotherapy.

Requirement for specific proteases in cancer cell intravasation as revealed by a novel semiquantitative PCR-based assay.

Proteases are crucial for cancer metastasis, but due to lack of assays, their role in intravasation has not yet been tested. We have developed a human Alu sequence PCR-based assay to quantitate intravasated cells in an in vivo model. We demonstrated that metalloproteinases (MMPs), and most likely MMP-9, are required for intravasation by showing that marimastat, an inhibitor of MMPs, reduced intravasation by more than 90%, and that only tumor cell lines expressing MMP-9 intravasated. Cells with low surface urokinase plasminogen activator (uPA) and uPA receptor (uPAR) were also incapable of intravasation, despite the presence of high levels of MMP-9. We concluded that breaching of the vascular wall is a rate-limiting step for intravasation, and consequently for metastasis, and that cooperation between uPA/uPAR and MMP-9 is required to complete this step.

[CD 143 expression in benign and malignant vascular tumors]. / CD 143 Expression in benignen und malignen vaskulären Tumoren.

The somatic form of CD 143 (angiotensin-I-converting enzyme) has been detected in many endothelial cells of the human body. Recently, we could identify local CD 143 overexpression in various pathological conditions e.g. in capillary endothelial proliferations at the border of myocardial infarctions and in coronary atherosclerotic plaques. Using monoclonal antibodies against CD 143, CD 31 and CD 34 we evaluated, whether CD 143 can serve as a marker of endothelial differentiation in vascular/perivascular tumors. 39 benign and malignant tumors, formalin-fixed, paraffin-embedded were investigated by APAAP immunohistochemistry using epitope retrieval techniques. Expression patterns were separately qualitatively and semiquantitatively analysed. Positive detection of epitopes was registered if more than 10% of the tumor cells were stained. CD 143 was detected in the majority of benign and malignant vascular tumors. All benign and malignant haemangioperizytomas were CD 143 negative. None of the markers detected all haemangioendotheliomas or all angiosarcomas, but the combination of CD 143 and CD 31 turned out to be positive in all haemangioendotheliomas and angiosarcomas. We conclude that most of the benign and malignant endothelial tumors express CD 143. The best discrimination of intermediate grade and malignant endothelial tumors can be achieved by analysis of the CD 143 and CD 31 co-expression.