Delayed post-traumatic trigger finger in a 14-year-old boy after blunt trauma. A case report

Although trigger finger is a common phenomenon, it is a rare condition in children and even more infrequently caused by a traumatic event. A case of a 14-year-old boy is reported, who presented with a prominent palmar nodule over a triggering middle finger and progressive flexion contracture, 6 months after a fall on the outstretched hand. An operation with resection of the A1-pulley and resection of the nodule, that showed chondroid metaplasia and calcifications, resolved the problem completely.

ZIC1 gene expression is controlled by DNA and histone methylation in mesenchymal proliferations

RNA and protein analysis revealed the consistent upregulation of the neural transcription factors ZIC1 and ZIC4 in desmoid tumors and other fibroproliferative disorders. The 5' flanking region of the ZIC1 promoter was unmethylated in desmoid tumor fibroblasts, while a hypermethylated ZIC1 promoter was found in human and mouse cell lines not expressing the gene. In addition, expressing cells showed a H3K4me2 at the ZIC1 promoter, whereas non-expressing cells showed higher levels of H3K9me2 in the same region. To our knowledge, this is the first report describing ZIC1 expression in mesenchymal proliferations and a role for DNA methylation in the control of ZIC1 expression.

Vascular endothelial growth factor counteracts the loss of phospho-Akt preceding motor neurone degeneration in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder that results in the selective loss of motor neurones. In the present study, the involvement of the antiapoptotic protein, Akt (protein kinase B), was studied. We found that motor neurones of both sporadic and familial ALS patients lack phospho-Akt, and that motor neurones of mutant SOD1 mice lose activated Akt early in the disease, before the onset of clinical symptoms. In vitro, overexpression of constitutively active Akt protects against mutant SOD1-dependent cell death. In vivo, levels of phospho-Akt in the spinal cord increase after intracerebroventricular administration of vascular endothelial growth factor to mutant SOD1 rats, a treatment we previously described to significantly protect motor neurones. From these results, we conclude that the loss of phospho-Akt could be involved in motor neurone death in ALS, and that therapies upregulating phospho-Akt thus might be of clinical relevance.

Non-invasive grading of brain tumours using dynamic amino acid PET imaging: does it work for 11C-methionine?

BACKGROUND

Static imaging of amino acids does not allow differentiation of low versus high grade brain tumours. It has been shown that dynamic imaging of the amino acid analogue (18)F-fluoroethyltyrosine (FET) can achieve this goal. In many centres, (11)C-methionine (MET) is used for tumour imaging, but no clinical studies on the use of dynamic scanning for grading have been performed.

METHODS

Thirty-four patients with primary brain glioma and histopathological confirmation were retrospectively studied using 40 min dynamic MET-PET with 220 MBq 11C-methionine. In relation to histopathological grading, various metabolic indices and temporal parameters as documented by Poepperl et al. (JNM 2006;47:393-403) were analyzed.

RESULTS

None of the evaluated static or temporal parameters allowed discrimination between high and low grade tumours. On average, low grade tumours showed washout after the initial uptake maximum, while both increases and decreases were seen for high grade tumours. Only the relative early versus late uptake ratio showed a trend towards significance (-0.16 +/- 0.17 for low grade versus 0.01 +/- 0.25 for high grade; p = 0.07).

CONCLUSION

Unlike FET-PET, the uptake characteristics of MET-PET do not allow classification of low and high grade tumours on an individual patient basis. Since literature data indicate that both tracers have a similar performance regarding biopsy location, tumour delineation, and detection of recurrence, FET-PET should be advocated over MET-PET as its uptake mechanism also allows noninvasive grading in glioma.

Trabectedin (ET-743): evaluation of its use in advanced soft-tissue sarcoma

Trabectedin (ET-743; Yondelis®) is a novel DNA-binding agent, originally derived from the marine tunicate, Ecteinascidia turbinata, and now produced synthetically. The efficacy of trabectedin in patients with advanced soft-tissue sarcoma has been demonstrated in three Phase II studies involving 189 previously treated patients. A pooled analysis of data from these studies showed that trabectedin induced tumor control (objective responses plus disease stabilization) in approximately 50% of patients; median overall survival was 10.3 months and progression-free survival at 6 months was 19.8%, with 29.3% of patients alive at 2 years. Responses were achieved in patients who were resistant to both doxorubicin and ifosfamide. Trabectedin is generally well tolerated, with adverse events being noncumulative, reversible and manageable. Unlike other commonly used cytotoxic agents, trabectedin is not associated with cardiotoxicity or neurotoxicity and alopecia is rare. Trabectedin is an interesting new anticancer agent that offers much promise for the treatment of advanced soft-tissue sarcoma.

Postradiation soft tissue sarcoma of the shoulder: a case report

We present a case of a postradiation soft tissue sarcoma of the shoulder in a patient with a hemiarthroplasty of the shoulder. Initially the patient was treated for an infection of the hemiarthroplasty but subsequent removal of the loose prosthesis and biopsy revealed the presence of a malignant tumour.

Stimulation of angiostatic platelet factor-4 variant (CXCL4L1/PF-4var) versus inhibition of angiogenic granulocyte chemotactic protein-2 (CXCL6/GCP-2) in normal and tumoral mesenchymal cells

Chemokines affect inflammation and cancer through leukocyte attraction and angiogenesis. Here, we demonstrate that CXCL4L1/platelet factor-4 variant (PF-4var), a highly angiostatic chemokine, is poorly chemotactic for phagocytes and is inducible in monocytes by inflammatory mediators but remained undetectable in macrophages and neutrophils. In addition, CXCL4L1/PF-4var production by mesenchymal tumor cells was evidenced in vitro and in vivo by specific ELISA and immunohistochemistry. CXCL4L1/PF-4var, but not CXCL4/PF-4, was coinduced with the angiogenic chemokine CXCL6/granulocyte chemotactic protein-2 (GCP-2) by cytokines, e.g., IL-1beta and IL-17, in sarcoma cells, but not in diploid fibroblasts. Furthermore, the induction of CXCL6/GCP-2 in endothelial cells by IL-1beta was enhanced synergistically by TNF-alpha but inhibited by IFN-gamma, which synergized with IL-1beta to produce the angiostatic CXCL10/IFN-gamma-induced protein-10. These findings indicate that the equilibrium between angiostatic and angiogenic factors during inflammation and tumor progression is rather complex and differs depending on the chemokine, cell type, and stimulus. Selective intervention in the chemokine network may drastically disturb this delicate balance of angiogenesis and tissue repair. Application of angiostatic CXCL4L1/PF-4var without attraction of protumoral phagocytes may be beneficial in cancer therapy.

Rapidly fatal Acanthamoeba encephalitis and treatment of cryoglobulinemia

We describe a 66-year-old woman with therapy-refractory cryoglobulinemia treated with rituximab, plasmapheresis, and steroids; a case of fatal meningoencephalitis caused by Acanthamoeba spp. then developed. Such infections are rare and show an unusually rapid course (possibly related to rituximab).

Primary epithelioid sarcoma of the oesophagus

Epithelioid sarcoma is a rare soft tissue tumour presenting two main variants: the 'classical' distal type and the more recently described proximal type. The latter is distinguished from the former by occurrence in elderly patients, more axial and deep location, prominent atypical and pleomorphic appearance and eventually aggressive clinical behaviour with poor outcome. To date, only few perivisceral epithelioid sarcomas have been described, and they are mainly related to the colon and bladder in pelvic and perineal sites. We report a hitherto undescribed epithelioid sarcoma of the distal oesophagus and discuss the relevance of molecular cytogenetics.

Natural course and clinical features of myxoid and round cell liposarcoma (MRCL) - a retrospective single center analysis

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Background and methods: MRCL, the 2nd most common type liposarcoma, represents ∼10 % of adult soft tissue sarcomas. In most pts the karyotypic hallmark is t(12;16)(q13;p11), leading to fusion of CHOP and FUS genes and generation of a hybrid protein. MRCL has unique sensitivity to antineoplastic agent ET-743 (Yondelis, Trabectidin), which induces specific morphological change and long-lasting response. We made a retrospective analysis of MRCL cases in our center. Results: 33 pts had histological diagnosis of MRCL with a mean (mn) follow-up of 45 mo (range, 2–214). By karyotyping or FISH analysis CHOP-FUS fusion was present in 12 and CHOP-EWS in 2 pts. The mn age at diagnosis was 45 yrs (range, 18–71), male:female ratio 1:0.8. Frequent primary sites: lower limb (25), abdomen (5), retroperitoneum (2), neck (2). Stage grouping at diagnosis: IA (2), IB (6), IIA (5), III (14), IV (2), not known (NK) (4). 2 had distant spread, 9 metachronous metastasis with a mn interval of 24 mo (range, 5–84). Main sites involved: abdomen (5), lung (3), bone (3). Surgery was performed with curative intent in 26/28 pts (5 NK), R0 resection in 23. 17/28 pts are alive without disease (16 previously R0-resected). 6/28 are alive with disease, 5 died due to MRCL. Relapse after R0 resection occurred after a mn of 24 mo (range, 5–84). Radiotherapy was used in 15/28 (5NK) with neoadjuvant (1), adjuvant (13) or palliative (3) intent (total doses 50–66 Gy). Chemotherapy (CT) was given in palliative (11) or neoadjuvant (1) fashion, after a mn of 1.3 surgical interventions (range, 0–3). 1st-line CT: doxorubicin- based combinations (7), single-agent doxorubicin (3), ET-743 (1). Best response: PR (5), NC (4), PD (1), NE (1). Mn duration of response was 6.3 mo (range, 1–15). 2nd-line CT: ET-743 (3), other agents (4). Best response: CR (1), PR (1), NC (3), PD (1), NE (1), with mn response duration of 7 mo (range, 1–13). 2 had further CT (PR 1, SD 1). Conclusions: MRCL is a chemosensitive sarcoma with variable clinical course. Local treatment can be curative, but systemic spread is frequent. Pts may respond to conventional CT or new agents such as ET-743. To evaluate the relative value of systemic treatment we need randomized trials in this unique clinical setting.

No significant financial relationships to disclose.

Tyrosine kinases as possible therapeutic targets in pulmonary artery intimal sarcoma

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Background: Pulmonary artery intimal sarcomas (PAIS) are very rare, highly malignant and clinically aggressive tumors, with yet elusive underlying pathogenic mechanisms and histogenesis. Our aim was to gain molecular insight in the oncogenic events leading to PAIS development, and to investigate the possibility of a pharmacological approach for the treatment of PAIS, specifically targeting the receptor tyrosine kinases (RTK) activated in these tumors. Methods: Fourteen cases of advanced high grade poorly differentiated PAIS were analyzed by immunohistochemistry and selectively by a variety of cytogenetic/molecular techniques, e.g. karyotyping, FISH, mRNA in situ hybridization, array-CGH, tyrosine kinases RT-PCR assay and Western blotting analysis. The study was supplemented by sequencing of PDGFRA, PDGFRB, KIT, VEGFR-1, VEGFR-2 and EGFR genes. Ex vivo functional assays were applied to test the sensitivity of PAIS primary tumor cells to different, clinically approved RTK inhibitors. Results: We demonstrate that (1) PAIS do not have mutations within the kinase domains of PDGFRs, KIT, VEGFRs or EGFR, (2) all cases show a similar cytogenetic molecular profile, characterized by amplification of PDGFRA/KIT/VEGFR2 and MDM2/CDK4 genes, while EGFR, PDGFRB and VEGFR1 are frequently polysomic but rarely highly amplified, (3) high level of expression of PDGFRA, VEGFR1/VEGFR2 and EGFR is uniformly present in the tested tumors, (4) PAIS demonstrate activation (phosphorylation) of PDGFRA and downstream PI3K-AKT and MAP-Kinase signaling pathways, (4) in ex vivo assays, a potent effect of BMS354825 on proliferation and survival of primary cells of PAIS is proven. Conclusions: PDGFRA is amplified and activated in PAIS, thus constituting one of many possible targets for the therapy. Tested inhibitors showed differential efficacy for inhibition of PAIS cells by ex vivo assays.

No significant financial relationships to disclose.

HMGA2 regulates transcription of the Imp2 gene via an intronic regulatory element in cooperation with nuclear factor-kappaB

IMP2 (insulin-like growth factor-II mRNA binding protein 2) is an oncofetal protein that is aberrantly expressed in several types of cancer. We recently identified the Imp2 gene as a target gene of the architectural transcription factor HMGA2 (high mobility group A2) and its tumor-specific truncated form HMGA2Tr. In this study, we investigated the mechanism via which HMGA2 regulates Imp2 gene expression. We show that HMGA2 and HMGA2Tr directly regulate transcription of the Imp2 gene by binding to an AT-rich regulatory region located in the first intron. In reporter experiments, we show that this AT-rich regulatory region mimics the response of the endogenous Imp2 gene to HMGA2 and HMGA2Tr. Furthermore, we show that a consensus nuclear factor-kappaB (NF-kappaB) binding site located immediately adjacent to the AT-rich regulatory region binds NF-kappaB and that NF-kappaB and HMGA2 cooperate to regulate Imp2 gene expression. Finally, we provide evidence that there is a strong and statistically significant correlation between HMGA2 and IMP2 gene expression in human liposarcomas.

An extrarenal rhabdoid tumor of the cervical spine with bony involvement

A case of a histologically proven rhabdoid tumor of the cervical spine in a 19-year-old Caucasian male is presented. Primary extrarenal rhabdoid tumors are very rare. When the central nervous system is involved, the tumor usually is located in the brain. Only three cases of primary spinal rhabdoid tumor have been reported. This case is the first reported extradural rhabdoid tumor of the spinal canal and the first case of a rhabdoid tumor located in the spinal canal with bony involvement.

Recurrent Low- to Intermediate-Grade Chondrosarcoma of the Thumb with Lung Metastases: An Objective Response to Trofosfamide

BACKGROUND

Low- to intermediate-grade chondrosarcoma is usually a slow-growing and highly chemotherapyresistant tumor type.

CASE REPORT

The 76-year-old female patient presented with low- to intermediate-grade chondrosarcoma of the distal phalanx of the right thumb in 1993 and was treated with an excision of the carpometacarpal joint. Approximately 10 years later, the patient presented with recurrent local disease at the trapezoid bone, which was resected. Eight months later she presented with local recurrence at the carpal joint and lung metastases. Subsequently she was treated chemotherapeutically with pegylated liposomal doxorubicin as part of a clinical trial. Due to tumor progression after 2 cycles, she was switched to oral trofosfamide (150 mg daily). A follow-up CT scan after 8 months demonstrated a partial remission that was confirmed by a second scan after 9 months of treatment. The treatment was well tolerated. After 18 months of continued treatment, she was still in remission and on trofosfamide.

CONCLUSION

Trofosfamide at a daily dose of 150 mg may be effective in low- to intermediate-grade chondrosarcoma.

Ecteinascidin-743: evidence of activity in advanced, pretreated soft tissue and bone sarcoma patients

Purpose. To evaluate the activity and safety of ecteinascidin (ET-743) in pretreated patients with advanced or metastatic soft tissue and bone sarcoma. Patients or subjects. Eighty-nine patients received ET-743 as a 24-hour continuous infusion at a dose of 900-1500 mug/m(2) every 3 weeks. Results. We observed one complete remission, 5 partial remissions, one minimal response, and 16 patients with a disease stabilization of 6 months or more. The objective response rate was 6.7% and the clinical benefit rate at 3 and 6 months was 37.7% and 23.4%, respectively. Responses were noted in patients with lipo-, leiomyo-, osteo-, and myogenic sarcoma, with a median duration of 9.85 months. Toxicity mainly involved an asymptomatic elevation of transaminases and neutropenia. Estimated 1- and 2-year survival rates were 39.4% and 15.8%. Median overall survival was 8.25 months. Discussion. This retrospective analysis confirms that ET-743 induces objective responses and progression arrest in a clinically relevant proportion of patients.

Rocuronium exacerbates mechanical ventilation-induced diaphragm dysfunction in rats

OBJECTIVE

Nondepolarizing neuromuscular blocking agents are commonly used in the intensive care setting, but they have occasionally been associated with development of myopathy. In addition, diaphragmatic atrophy and a reduction in diaphragmatic force were reported after short-term controlled mechanical ventilation in animal models. We hypothesized that infusion of rocuronium, an aminosteroidal neuromuscular blocking agent, during 24 hrs of controlled mechanical ventilation would further alter diaphragm function and would enhance activation of the ubiquitin- proteasome pathway.

DESIGN

Randomized, controlled experiment.

SETTING

Basic animal science laboratory.

SUBJECTS

Male Wistar rats, 14 wks old.

INTERVENTIONS

Rats were divided into four groups: a control group, a group of anesthetized rats breathing spontaneously for 24 hrs, and two groups submitted to mechanical ventilation for 24 hrs, receiving a continuous infusion of either 0.9% NaCl or rocuronium.

MEASUREMENTS AND MAIN RESULTS

In vitro diaphragm force was decreased more significantly after 24 hrs of mechanical ventilation combined with rocuronium infusion than after mechanical ventilation alone (e.g., tetanic force, -27%; p < .001 vs. mechanical ventilation). Similarly, the decrease in diaphragm type IIx/b fiber dimensions was more pronounced after mechanical ventilation with rocuronium treatment than with saline treatment (-38% and -29%, respectively; p < .001 vs. control). Diaphragm hydroperoxide levels increased similarly in both mechanically ventilated groups. Diaphragm muscle RING-finger protein-1 (MURF-1) messenger RNA expression, an E3 ligase of the ubiquitin-proteasome pathway, increased after mechanical ventilation (+212%, p < .001 vs. control) and increased further with combination of rocuronium (+320%, p < .001 vs. control). Significant correlations were found between expression of MURF-1 messenger RNA, diaphragm force, and type IIx/b fiber dimensions.

CONCLUSIONS

Infusion of rocuronium during controlled mechanical ventilation leads to further deterioration of diaphragm function, additional atrophy of type IIx/b fibers, and an increase in MURF-1 messenger RNA in the diaphragm, which suggests an activation of the ubiquitin-proteasome pathway. These findings could be important with regard to weaning failure in patients receiving this drug for prolonged periods in the intensive care unit setting.

Intestinal neurofibromatosis is a subtype of familial GIST and results from a dominant activating mutation in PDGFRA

BACKGROUND & AIMS

Intestinal neurofibromatosis (Online Mendelian inheritance in Man database number 162220) is an alternate form of neurofibromatosis. Patients present with neurofibromas limited to the intestine in the absence of any other typical features of NF1 and NF2. At present, the molecular basis of intestinal neurofibromatosis remains elusive. The aim of the present study was to find the gene responsible for intestinal neurofibromatosis and to characterize functionally the mutation.

METHODS

Three candidate genes (NF1, KIT, and PDGFRA) were screened for mutations in 3 sisters diagnosed with intestinal neurofibromatosis. Five tumors were available for pathologic examination. Activation (phosphorylation) of PDGFRalpha was subsequently tested by Western blot analysis on a transfected 293T and Ba/F3 cell line.

RESULTS

We found an inherited mutation (Y555C) in the juxtamembrane domain of PDGFRA in the affected individuals. The Y555C mutation leads to autophosphorylation and thus activation of PDGFRalpha. These observations confirm that PDGFRalpha(Y555C) is an oncogenic kinase. The clinical phenotype in the reported family resembles the syndrome of familial gastrointestinal stromal tumors (familial GIST). Somatic activating mutations in KIT and PDGFRA are frequent in sporadic GISTs, and mutations in both genes have also been described in familial GISTs. The tumors in the reported family are morphologically identical to intestinal neurofibromas, but, immunohistochemically, they do not express S100 or any of the known GIST markers.

CONCLUSIONS

The inherited PDGFRA mutation in the reported family shows that intestinal neurofibromatosis is allelic to familial GIST caused by PDGRA mutations. We therefore propose that these tumors be classified as familial KIT-negative gastrointestinal stromal tumors.

An external cause for 'idiopathic' pachymeningitis?

In a 67-year-old man with a history of professional asbestos exposure and persistent headaches since one year, a diagnosis of idiopathic pachymeningitis was made. IHCP (idiopathic hypertrophic cranial pachymeningitis) is in literature referred to as one of the presentations of Multifocal Idiopathic Fibrosclerosis or MIF, representing a group of fibro-inflammatory and pathologically similar diseases, including also retroperitoneal fibrosis, mediastinal fibrosis and sclerosing cholangitis. Since recent literature links asbestos exposure to a risk of development of retroperitoneal fibrosis, the present case suggests to focus in future research of IHCP on possible external causes.

Efficacy of the kinase inhibitor SU11248 against gastrointestinal stromal tumor mutants refractory to imatinib mesylate

PURPOSE

The majority of gastrointestinal stromal tumors harbor mutations in the receptor tyrosine kinases KIT or platelet-derived growth factor receptor A (PDGFRA), and respond to treatment with the tyrosine kinase inhibitor imatinib. Some tumors, however, show primary resistance to imatinib treatment, and most others become resistant during treatment. The most common mechanism of imatinib resistance involves specific mutations in the kinase domains of KIT or PDGFRA. We tested the activity of SU11248, an orally active small-molecule tyrosine kinase inhibitor, to inhibit important imatinib-resistant KIT and PDGFRA mutants.

EXPERIMENTAL DESIGN

Primary imatinib-resistant tumor cells and cell lines expressing clinically identified imatinib-resistant KIT-V654A, KIT-T670I, or PDGFRA-D842V mutant isoforms were evaluated for sensitivity to SU11248 by Western immunoblotting and proliferation assays. Three patients with the KIT-V654A mutation were treated with SU11248.

RESULTS

Based on ex vivo assays, SU11248 potently inhibits KIT kinase activity of V654A and T670I mutants and suppresses proliferation of the cells expressing these mutations. Sensitivity of KIT-V654A and KIT-T670I mutants to SU11248 was confirmed using cell lines expressing these mutants. In contrast, SU11248 did not potently inhibit the PDGFRA-D842V mutant. In agreement with these results, two of the three imatinib-resistant patients with the KIT-V654A mutation responded to SU11248 treatment.

CONCLUSIONS

These studies suggest that SU11248 may be a useful therapeutic agent to treat gastrointestinal stromal tumors harboring the imatinib-resistant KIT-V654A or KIT-T670I mutations, but it has no effect on the activity of the PDGFRA-D842V mutant. Specific kinase inhibitors should be designed to inhibit the constitutive activating PDGFRA mutation at codon 842.