Beta-catenin overexpression in Dupuytren's disease is unrelated to disease recurrence

Recurrence of Dupuytren's contracture is common yet unpredictable, compromising surgical outcome. The alpha-smooth muscle actin-containing myofibroblast is the active contractile cellular component. Based on recent reports on beta-catenin accumulation in Dupuytren's disease, we investigated a possible relation with disease recurrence. We divided a collection of 143 nodules into those from patients with recurrent or nonrecurrent nodules and with a minimal 3-year followup. We randomly selected 12 and 11 samples of each group, respectively. We looked at Dupuytren's diathesis, immunohistologic staining for beta-catenin and alpha-smooth muscle actin, and Luck's histologic stages (zones). The expression of selected Wnt genes was examined with TaqMan PCR in separate histologic zones. All samples showed cytoplasmic and nuclear beta-catenin accumulation in myofibroblasts in involutional zones. The risk score of Abe et al. and Dupuytren's diathesis were greater in the recurrent group. Greater Wnt5a expression in the beta-catenin-accumulating involutional zone was seen. We conclude intracellular beta-catenin accumulation, possibly regulated by upstream Wnt signaling pathway activation and confined in myofibroblasts in the involutional zone of Dupuytren's diathesis, is unrelated to disease recurrence. Clinical parameters for Dupuytren's diathesis remain the best way to predict recurrence risk.

The effects of electrical stimulation or an electrolytic lesion in the mediodorsal thalamus of the rat on survival, body weight, food intake and running activity in the activity-based anorexia model

The glucose metabolism in the mediodorsal thalamus (MD) is increased in rats in the activity-based anorexia (ABA) model. In patients, electrical stimulation in hyperactive brain regions reduced symptoms in e.g. major depressive disorder and cluster headache. In two blinded randomised controlled experiments, we therefore examined the effects of high-frequency electrical stimulation and an electrolytic lesion in the MD in a validated rat model for anorexia nervosa. The ABA model was successfully replicated in all our experiments, with a reduction in body weight, food intake, and survival time and an increase in running activity. In a first experiment, we evaluated the effect of electrical stimulation or a curative lesion in the MD on survival, body weight, food intake and locomotor activity in ABA rats. Electrical MD stimulation or an electrolytic MD lesion did not improve the symptoms of rats in the ABA model, compared to control groups. In a second experiment, we investigated the effect of a preventive electrolytic lesion in the MD on rats in the ABA model. Although there was no significant improvement of survival, body weight and food intake, locomotor activity was significantly reduced in the lesion group compared to the control group. Apart from this positive effect on running activity, we found no convincing evidence for the suitability of the MD as a neuromodulation target for anorexia nervosa patients.

Metallosis in revision total elbow arthroplasty. Complications and staging method

Although total elbow arthroplasty is a reliable treatment method for the arthritic joint, revision is necessary if loosening, instability, wear, fracture or infection occurs. We report 12 patients with 19 months (10-29) follow-up after revision arthroplasty for painful loosening in six cases, periprosthetic fracture in three, gross instability in one and skin perforation with possible infection in two. All cases presented with severe metallosis. Fractures were seen in four, triceps insufficiency in three and skin perforation in two. All patients were treated with exchange arthroplasty using the Coonrad-Morrey prosthesis. Three patients had in addition strut-allografting. The two patients with skin perforation and possible infection had a staged procedure. Mayo Elbow Performance Score improved from 24 to 87 with uneventful healing, fracture consolidation and allograft incorporation. At follow-up, triceps insufficiency persisted in all three cases. Transient neuropathy was present in five patients (4 ulnar, 1 radial). Metallosis in total elbow arthroplasty may be associated with severe tissue damage. A staging method is presented.

Predominant fiber atrophy and fiber type disproportion in early ullrich disease

Ullrich disease (congenital muscular dystrophy type Ullrich, UCMD) is a severe congenital disorder of muscle caused by recessive and dominant mutations in the three genes that encode the alpha-chains of collagen type VI. Little is known about the early pathogenesis of this myopathy. The aim of this study was to investigate early histological changes in muscle of patients with molecularly confirmed UCMD. Muscle biopsies were analyzed from 8 UCMD patients ranging in age from 6 to 30 months. Type I fiber atrophy and predominance were seen early, together with a widening of the fiber diameter spectrum, whereas no dystrophic features were apparent. A subpopulation of more severely atrophic type I fibers was apparent subsequently, including one biopsy that fulfilled the formal diagnostic criteria of histopathological fiber type disproportion (FTD). Thus, early in the disease, UCMD presents as a non-dystrophic myopathy with predominant fiber atrophy. Collagen VI mutations also qualify as a cause of fiber type disproportion.

MGMT promoter hypermethylation correlates with a survival benefit from temozolomide in patients with recurrent anaplastic astrocytoma but not glioblastoma

AIMS

To investigate the correlation between O(6)-methylguanine-DNA-methyltransferase (MGMT) promoter methylation and benefit from temozolomide in patients with recurrent high-grade glioma.

PATIENTS AND METHODS

A real-time, quantitative, methylation-specific PCR assay was performed on archival tissue blocks from patients treated with temozolomide at the first recurrence.

RESULTS

A subgroup of 38 patients who were chemotherapy-naive at recurrence was analysed (22 glioblastoma, 12 anaplastic astrocytoma [AA] and 4 anaplastic oligoastrocytoma [AOA]); none had 1p/19q loss. Among 10 (26%) patients with a hypermethylated MGMT promoter, none experienced disease progression within the first two treatment cycles compared with 12 of 28 (43%) patients with an unmethylated promoter (p=0.016). By Cox multivariate analysis, tumour grade and MGMT promoter methylation correlated with time to progression (p<0.05); MGMT promoter methylation correlated with superior overall survival in AA/AOA but not in glioblastoma.

CONCLUSIONS

MGMT promoter methylation predicted a survival benefit in patients with 1p/19q intact AA/AOA treated with temozolomide at recurrence.

Activity of dasatinib, a dual SRC/ABL kinase inhibitor, and IPI-504, a heat shock protein 90 inhibitor, against gastrointestinal stromal tumor-associated PDGFRAD842V mutation

PURPOSE

Activating mutations in platelet-derived growth factor receptor-alpha (PDGFRA) have been reported in approximately 5% to 10% of patients with gastrointestinal stromal tumors (GIST). Imatinib efficiently inhibits the juxtamembrane PDGFRA mutations, whereas many tyrosine kinase domain activation loop PDGFRA mutations confer primary resistance to imatinib. In this study, we compared the efficacy of second-line tyrosine kinase inhibitors such as dasatinib, sorafenib, and nilotinib against two GIST-related PDGFRA mutants, PDGFRA(D842V) and PDGFRA(DeltaDIM842-844). In addition, we sought to investigate the inhibitory effect of the heat shock protein 90 inhibitor, IPI-504, on these mutants.

EXPERIMENTAL DESIGN

Primary imatinib-resistant tumor cells and cell lines expressing imatinib-resistant PDGFRA(D842V) or imatinib-sensitive PDGFRA(DeltaDIM842-844) mutants were treated with different concentrations of dasatinib, sorafenib, nilotinib, and IPI-504. The effect of treatment on proliferation, survival, and signaling was determined.

RESULTS

All inhibitors tested exhibited a high efficacy toward the PDGFRA(DeltaDIM842-844) mutant. In contrast, ex vivo and in vitro assays revealed that only dasatinib potently inhibited the PDGFRA(D842V) isoform with an IC(50) value of 62 nmol/L. Sorafenib and nilotinib were significantly less efficacious against this mutation, inhibiting the PDGFRA kinase activity at >1,000 and >5,000 nmol/L, and suppressing the proliferation of the cells expressing the PDGFRA(D842V) mutant with an IC(50) value of 239 and 1,310 nmol/L, respectively. IPI-504 treatment potently inhibited PDGFRA kinase activity by inducing the degradation of PDGFRA(D842V) and PDGFRA(DeltaDIM842-844) at 256 and 182 nmol/L, respectively.

CONCLUSIONS

Treatment with dasatinib or the heat shock protein 90 inhibitor IPI-504 may provide a therapeutic alternative for GIST patients whose tumors carry the imatinib-resistant PDGFRA(D842V) mutant isoform.

Multiple primary sporadic gastrointestinal stromal tumors in the adult: an underestimated entity

PURPOSE

Gastrointestinal stromal tumors (GIST) are commonly regarded as solitary tumors. The occurrence of multiple lesions is considered an extraordinary event restricted to pediatric GISTs and rare hereditary conditions. Beyond these well-defined situations, the presentation of multiple synchronous lesions is commonly viewed as the result of the metastatic spreading of a single primary GIST. Based on this axiom, patients with multifocal disease are classified as advanced stage and treated as such. Whether, indeed, the detection of several lesions in sporadic adult GIST patients may be suggestive of phenomena of tumor multiplicity still needs to be clarified.

EXPERIMENTAL DESIGN

From a multicentric series of 442 consecutive cases, 26 of which with advanced disease, we selected 5 patients who presented up to three distinct GIST nodules. Five additional cases with similar characteristics were also contributed by two other institutions. The clonal relationship between the synchronous lesions was assessed by comparing KIT/PDGFRA mutation and microsatellite pattern.

RESULTS

An independent origin of the synchronous lesions was established in 6 of 10 cases. Notably, in one patient, one lesion arose in the peritoneum, which is ordinarily regarded as a site of metastasis.

CONCLUSIONS

Our data indicate that a significant fraction of GIST patients with multifocal presentation are actually affected by multiple primary tumors, suggesting that mesenchymal GIST precursor cells of these individuals are somehow primed to transformation. Thus, in the presence of multifocal GIST manifestations, an accurate characterization of the different tumor sites should be undertaken for a proper patient staging and therapy planning.

Postoperative adjuvant dendritic cell-based immunotherapy in patients with relapsed glioblastoma multiforme

PURPOSE

To investigate the therapeutic role of adjuvant vaccination with autologous mature dendritic cells (DC) loaded with tumor lysates derived from autologous, resected glioblastoma multiforme (GBM) at time of relapse.

EXPERIMENTAL DESIGN

Fifty-six patients with relapsed GBM (WHO grade IV) were treated with at least three vaccinations. Children and adults were treated similarly in three consecutive cohorts, with progressively shorter vaccination intervals per cohort. Feasibility and toxicity were assessed as well as effect of age, extent of resection, Karnofsky Performance Score, and treatment cohort on the progression-free (PFS) and overall survival (OS) using univariable and multivariable analysis.

RESULTS

Since the prevaccine reoperation, the median PFS and OS of the total group was 3 and 9.6 months, respectively, with a 2-year OS of 14.8%. Total resection was a predictor for better PFS both in univariable analysis and after correction for the other covariates. For OS, younger age and total resection were predictors of a better outcome in univariable analysis but not in multivariable analysis. A trend to improved PFS was observed in favor of the faster DC vaccination schedule with tumor lysate boosting. Vaccine-related edema in one patient with gross residual disease before vaccination was the only serious adverse event.

CONCLUSION

Adjuvant DC-based immunotherapy for patients with relapsed GBM is safe and can induce long-term survival. A trend to PFS improvement was shown in the faster vaccination schedule. The importance of age and a minimal residual disease status at the start of the vaccination is underscored.

Electrical stimulation in the lateral hypothalamus in rats in the activity-based anorexia model

Object

One quarter of patients with anorexia nervosa have a poor outcome and continue to suffer chronically or die. Electrical brain stimulation may be of therapeutic benefit in some of these patients; however, the brain target for inducing symptom relief is unknown. In this study, the authors evaluated the effects of acute and chronic electrical stimulation in the lateral hypothalamus on food intake, locomotor activity, and survival time in rats in an activity-based anorexia model.

Methods

In an acute experiment, the authors electrically stimulated at 100 Hz and 0, 25, 50 and 75% of the maximal stimulation amplitude (that is, the amplitude leading to severe side effects) in the lateral hypothalamus on consecutive days during 4 test sessions in 10 rats and evaluated food intake and locomotor activity. In a chronic experiment, they compared food intake, wheel revolutions, and survival time between 6 rats that underwent electrical stimulation in the lateral hypothalamus (50% of maximal stimulation amplitude) and 8 rats that did not undergo stimulation.

Results

In the acute experiment, overall electrical stimulation (25, 50, and 75% combined) and stimulation at 75% of the maximal stimulation amplitude significantly decreased the locomotor activity. However, if the authors omitted results of 1 rat, in which the electrode tip was not located in the lateral hypothalamus on one side but rather in the supraoptic chiasm, the remaining results did not yield significance. No other differences were observed.

Conclusions

When the findings of the current study are extrapolated to patients with anorexia nervosa, the authors do not expect major effects on symptoms with electrical stimulation at high frequency in the lateral hypothalamus.

Myxoid tumours of soft tissue: the so-called myxoid extracellular matrix is heterogeneous in composition

AIM

Myxoid tumours of soft tissue are characterized by their so-called 'myxoid' extracellular matrix. The aim was to investigate the composition and possible function of this matrix which is poorly understood.

METHODS AND RESULTS

Using Alcian Blue staining with and without pretreatment with hyaluronidase and application of the critical electrolyte concentration method followed by densitometry, the glycosaminoglycan composition of three different myxoid tumours was studied. The composition of glycosaminoglycans varied with tumour type and grade, despite their general characterization as myxoid tumours. Intramuscular myxoma contained similar amounts of the various glycosaminoglycans as grade I myxofibrosarcoma; grade III myxofibrosarcoma contained less hyaluronic acid and more heparan sulphate, whereas extraskeletal myxoid chondrosarcoma contained predominantly chondroitin-4 and -6 sulphates. Western blot identified albumin as a major protein in tumour lysates, and its presence in the extracellular matrix and cytoplasm of the majority of tumours was demonstrated by immunohistochemistry; production of albumin by the tumour cells was confirmed by quantitative polymerase chain reaction.

CONCLUSIONS

The extracellular matrix of myxoid tumours of soft tissue has a heterogeneous composition consisting of, amongst others, glycosaminoglycans and albumin, which appear to play an active role in their morphogenesis.

Clinicopathologic profile of gastrointestinal stromal tumors (GISTs) with primary KIT exon 13 or exon 17 mutations: a multicenter study on 54 cases

Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms driven by oncogenic, mutational activation of KIT or platelet-derived growth factor receptor alpha (PDGFRA). GIST-specific KIT or PDGFRA mutations have been linked to tumor location, tumor cell morphology and clinical behavior. The purpose of this study was to evaluate the clinicopathologic profile of GISTs that have KIT exon 13 or exon 17 mutations. Through the collaboration of several GIST research groups, we gathered 54 cases from the pre-imatinib era that had such primary mutations. From our observations and those in the literature, we estimate that the frequency of these mutations is no higher than 1-2%. Almost all (32 of 33, 97%) of the KIT exon 13 mutations were the 1945A>G substitution leading to Lys642Glu. A majority (15 of 21, 71.4%) of the KIT exon 17 mutations were the 2487T>A substitution leading to Asn822Lys. Demographic and clinicopathologic data were available for 26 and 14 KIT exon 13 and exon 17 mutant GISTs, respectively. Median age and male to female ratio were similar to ones reported in other GIST studies. Small intestinal tumors were two times more frequent than gastric ones among KIT exon 17 mutants. Also, intestinal tumors were slightly overrepresented among KIT exon 13 mutants when compared with population-based studies. The majority of KIT exon 13 or exon 17 mutants had a spindle-cell morphology and only a few had epithelioid features. Tumor size varied from 1.2 to 25 cm and average mitotic rates were 9.5 and 4.2 for KIT exon 13 and exon 17 mutants, respectively. Gastric KIT exon 13 mutant GISTs tend to be slightly larger and more aggressive than gastric GISTs in average, whereas the behavior of small intestinal GISTs with KIT exon 13 mutations does not differ from other small intestinal GISTs. The latter is also true for all KIT exon 17 mutant GISTs.

Rectal gastrointestinal stromal tumors associated with a novel germline KIT mutation

Somatic, activating mutations of KIT or PDGFRA are early oncogenic events in the majority of sporadic gastrointestinal stromal tumors (GISTs). Also a number of families with GISTs have been described in recent years. The familial GIST syndrome is a rare autosomal dominant disorder with high penetrance and diverse manifestations associated mostly with germline KIT mutations. In this report, we show a novel germline mutation in the juxtamembrane domain of KIT, identified in 2 brothers, both presenting with recurrent, high risk/malignant rectal GISTs. The KIT p.Q575_P577delinsH mutation was found in tumor samples as well as in peripheral blood leukocytes from both patients, proving that the mutation was indeed inherited. Besides rectal GISTs, no other features characteristic for the familial GIST syndrome was observed in either brother or any of their first-degree relatives. The patients were treated with imatinib, achieving either long-term partial response or stable disease. This observation confirms that imatinib can be successfully used in familial GISTs, as it is used in the sporadic advanced tumors, and that tumors bearing a KIT p.Q575_P577delinsH mutation are responsive to imatinib treatment.

Neuronal inclusion protein TDP-43 has no primary genetic role in FTD and ALS

The nuclear TAR DNA binding protein (TDP-43) is deposited in ubiquitin-positive inclusions in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), two clinicopathologically overlapping neurodegenerative diseases. In this study we excluded mutations and copy number variations in the gene encoding TDP-43 (TARDBP) from an extended series of 173 FTD and 237 ALS patients. Further, we did not identify association of common genetic variants in these patients. Our data implicate that TDP-43 has no primary genetic role in the pathophysiological mechanisms underlying central nervous system neurodegeneration in these diseases.

Posttransplant Epstein-Barr virus-associated myogenic tumors: case report and review of the literature

Epstein-Barr virus (EBV) has been implicated in the pathogenesis of different types of malignancies. While nonmelanoma skin cancers, lymphomas and Kaposi sarcomas are the most frequently reported malignancies after solid organ transplantation, EBV-associated smooth muscle tumors (EBV-SMT) after transplantation are rare and thus far only 18 cases in kidney recipients have been reported. A case of a 51-year-old kidney transplant recipient diagnosed with EBV-SMT is reported together with a review of the literature.

aP2-Cre-mediated expression activation of an oncogenic PLAG1 transgene results in cavernous angiomatosis in mice

The developmentally regulated PLAG1 proto-oncogene has been implicated in the development of various human tumor types, such as pleomorphic salivary gland adenomas, lipoblastomas, hepatoblastomas and AML. In previous studies, we generated two independent PLAG1 transgenic founder strains, PTMS1 and PTMS2, in which PLAG1 could be activated via Cre-mediated excision of a stop cassette. With these founders, PLAG1-induced tumor formation in salivary and mammary glands of mice was studied. To further delineate the oncogenic spectrum of PLAG1 in mice, we induced aP2-Cre-mediated overexpression of PLAG1 in offspring from crossbreeding PTMS1 mice with aP2-Cre transgenic mice. More than 80% of aP2-Cre(+/-)/PLAG1(+/-) (P1-ACre) mice developed a vascular tumor type within one year, which could be classified histopathologically as cavernous angiomatosis. The lesions occurred in various regions of the mouse body but almost exclusively in the immediate surrounding of fat cells. Validation of available PLAG1-induced gene expression profiling data, using targeted tissues, revealed that expression activation of PLAG1 is functional because it leads to elevated levels of PLAG1 target gene transcripts in those tissues, such as for instance those of H19, Dlk1, and Igf-2, similarly as observed in PLAG1-induced salivary and mammary gland tumors. In conclusion, we present the first evidence that links PLAG1 to the molecular pathogenesis of vascular tumorigenesis, known as cavernous angiomatosis, with the possible involvement of Igf signaling and, moreover, further delineate the oncogenic spectrum of PLAG1 in mice, increasing the potential of this transgenic mouse tumor model system for research and therapeutic drug testing.

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.