CD44 expression in benign and malignant colorectal polyps

PURPOSE: This retrospective study was undertaken to evaluate immunohistochemically the expression of CD44 standard protein and CD44v5 and CD44v6 isoforms in colorectal adenomas and early invasive cancers developing within adenomas as possible markers characterizing colorectal polyps with a more aggressive biologic potential. METHODS: Archival tissues of 81 consecutive locally resected colorectal polyps, comprising 57 colorectal adenomas and 24 carcinomas-in-adenomas, were stained immunohistochemically with the use of commercially available mouse monoclonal antibodies: SFF-2 for CD44 standard protein, VFF-8 for CD44v5, and VFF-7 for CD44v6. RESULTS: Sixtythree percent of the colorectal polyps were positive for CD44 standard protein, 59 percent were positive for CD44v5, and 27 percent were positive for CD44v6. Ninetythree percent of the low-grade adenomas were CD44 standard protein-positive, in contrast to 50 percent of the high-grade adenomas and only 42 percent of the carcinomas-in-adenomas (Kendall's Tau =–0.42;P<0.0001). CD44v6 expression was more frequently found in early invasive cancers (54 percent) than in high-grade adenomas (25 percent) and low-grade adenomas (7 percent). This difference also was statistically significant (Kendall's Tau-b =0.39;P=0.00003). Surprisingly, a downregulation of CD44 standard protein expression was observed in the adenoma tissue adjacent to carcinomas (62 percent) and areas with high-grade atypia (71 percent), compared with low-grade adenomas (93 percent; Kendall's Tau-b =–0.28;P=0.004). CONCLUSIONS: Our data suggest that CD44 standard protein and CD44 isoform v6 expression differs considerably in benign and malignant colorectal polyps. Clinical studies with larger patient groups could clarify the prognostic potential of CD44 further     

Sinusoidal Obstruction Syndrome of the Liver after Hematopoietic Stem Cell Transplantation: Decision Making for Orthotopic Liver Transplantation

Sinusoidal obstruction syndrome (SOS) is a specific complication of hematopoietic stem cell transplantation (HSCT) that can lead to substantial morbidity and treatment-related mortality. Heparin is frequently used as prophylaxis of and defibrotide as therapy for mild to moderate SOS. In severe cases of SOS these therapies are often ineffective, and orthotopic liver trans-plantation (OLT) may be the only option. Reports in the literature about the outcome of liver transplantation for SOS are contradictory. We describe our second case of OLT after HSCT. The patient died of intracranial hemorrhage 2 weeks after liver transplantation with good initial organ function. In the first case at our center, however, the patient survived more then 8 years. The reported short- to medium-range survival rate for OLT following HSCT is approximately 50%. On the basis of the experience at our center and the findings in a review of the literature, we developed a rational approach to the selection for liver transplantation of patients with life-threatening liver dysfunction after marrow transplantation.     

Does δ-sarcoglycan-associated autosomal-dominant cardiomyopathy exist?

In this study we clinically and genetically characterize a consanguineous family with a homozygous novel missense mutation in the δ-sarcoglycan gene and a second δ-sarcoglycan mutation that has previously been reported to cause severe autosomal-dominant dilated cardiomyopathy. We identified a novel missense mutation in exon 6 (p.A131P) of the δ-sarcoglycan gene, which in a homozygous state leads to the clinical picture of a limb girdle muscular dystrophy. In four heterozygous carriers for the mutation, aged 3–64 years, a second sequence variant in exon 6 (p.S151A) of the δ-sarcoglycan gene was detected on the other allele. This second missense change had previously been reported to be responsible for fatal autosomal-dominant dilated cardiomyopathy at young age. Comprehensive clinical and cardiac investigation in all of the compound heterozygous family members revealed no signs of cardiomyopathy or limb girdle muscular dystrophy. Our findings demonstrate that, even in the presence of a second disease-causing mutation, the p.S151A mutation in the δ-sarcoglycan gene does not result in cardiomyopathy. This finding questions the pathological relevance of this sequence variant for causing familial autosomal-dominant dilated cardiomyopathy and thereby the role of the δ-sarcoglycan gene in general as a disease-causing gene for autosomal-dominant dilated cardiomyopathy.     

The PML domain of PML–RARα blocks senescence to promote leukemia

In most acute promyelocytic leukemia (APL) cases, translocons produce a promyelocytic leukemia protein–retinoic acid receptor α (PML–RARα) fusion gene. Although expression of the human PML fusion in mice promotes leukemia, its efficiency is rather low. Unexpectedly, we find that simply replacing the human PML fusion with its mouse counterpart results in a murine PML–RARα (mPR) hybrid protein that is transformed into a significantly more leukemogenic oncoprotein. Using this more potent isoform, we show that mPR promotes immortalization by preventing cellular senescence, impeding up-regulation of both the p21 and p19^ARF cell-cycle regulators. This induction coincides with a loss of the cancer-associated ATRX/Daxx–histone H3.3 predisposition complex and suggests inhibition of senescence as a targetable mechanism in APL therapy.Acute promyelocytic leukemia (APL) is characterized by chromosomal translocations involving retinoic acid receptor alpha (RARα) with a limited number of translocation partners. A common feature of APL-promoting fusion proteins is their ability to self-associate. Indeed, previous studies have shown that fusion of RARα with self-associating domains is sufficient to render RARα leukemogenic (1). In APL patients, the predominant leukemogenic protein found in 95–99% of cases is the result of the fusion of promyelocytic leukemia protein (PML) with RARα (human PML–RARα; hPR) (2, 3). RARα and PML are regulatory proteins implicated in multiple aspects of differentiation and development (4) and apoptosis and cellular senescence (5, 6), respectively. Despite speculation, the relevance of senescence in APL is not fully understood (7, 8).Current mouse models recapitulate many key features of the human disease, including a malignant promyelocytic phenotype and sensitivity to all-trans retinoic acid (ATRA), but suffer from incomplete penetrance and long latency until disease presentation (1, 9, 10). We reasoned that the relatively low leukemogenic activity of hPR in mice might be due to modest sequence identity between human and mouse PML (PML: 63% identity; RARα: 98% identity). Consistent with this notion, we have designed an “experimental oncoprotein” corresponding to the fusion of mouse PML with RARα (mPR), which produced myelocytic leukemia similar to hPR-induced murine APL (10) but with higher penetrance and shorter latency periods. Notably, expression of mPR disrupted PML nuclear bodies (PML-NBs), phenocopying hPR-induced APL (11, 12). We show here that senescence-related up-regulation of p21 and p19 is completely lost in primary murine bone marrow cells upon expression of mPR. Furthermore, we find that the assembly of the death domain associated protein (Daxx)–alpha thalassemia/mental retardation syndrome X-linked (ATRX) complex at PML-NBs is disrupted by mPR expression, implicating this PML–ATRX–Daxx (PAX) complex in cellular senescence and tumor suppressor activity for PML (13). This study provides experimental evidence for the relevance of PML-NB disruption in APL genesis.     

Global and regional left ventricular myocardial deformation measures by magnetic resonance feature tracking in healthy volunteers: comparison with tagging and relevance of gender

Background

Feature Tracking software offers measurements of myocardial strain, velocities and displacement from cine cardiovascular magnetic resonance (CMR) images. We used it to record deformation parameters in healthy adults and compared values to those obtained by tagging.

Methods

We used TomTec 2D Cardiac Performance Analysis software to derive global, regional and segmental myocardial deformation parameters in 145 healthy volunteers who had steady state free precession (SSFP) cine left ventricular short (basal, mid and apical levels) and long axis views (horizontal long axis, vertical long axis and left ventricular out flow tract) obtained on a 1.5 T Siemens Sonata scanner. 20 subjects also had tagged acquisitions and we compared global and regional deformation values obtained from these with those from Feature Tracking.

Results

For globally averaged measurements of strain, only those measured circumferentially in short axis slices showed reasonably good levels of agreement between FT and tagging (limits of agreement −0.06 to 0.04). Longitudinal strain showed wide limits of agreement (−0.16 to 0.03) with evidence of overestimation of strain by FT relative to tagging as the mean of both measures increased. Radial strain was systematically overestimated by FT relative to tagging with very wide limits of agreement extending to as much as 100% of the mean value (−0.01 to 0.23). Reproducibility showed similar relative trends with acceptable global inter-observer variability for circumferential measures (coefficient of variation 4.9%) but poor reproducibility in the radial direction (coefficient of variation 32.3%). Ranges for deformation parameters varied between basal, mid and apical LV levels with higher levels at base compared to apex, and between genders by both FT and tagging.

Conclusions

FT measurements of circumferential but not longitudinally or radially directed global strain showed reasonable agreement with tagging and acceptable inter-observer reproducibility. We record provisional ranges of FT deformation parameters at global, regional and segmental levels. They show evidence of variation with gender and myocardial region in the volunteers studied, but have yet to be compared with tagging measurements at the segmental level.     

Metabolite ratios as potential biomarkers for type 2 diabetes: a DIRECT study

Aims/hypothesis

Circulating metabolites have been shown to reflect metabolic changes during the development of type 2 diabetes. In this study we examined the association of metabolite levels and pairwise metabolite ratios with insulin responses after glucose, glucagon-like peptide-1 (GLP-1) and arginine stimulation. We then investigated if the identified metabolite ratios were associated with measures of OGTT-derived beta cell function and with prevalent and incident type 2 diabetes.

Methods

We measured the levels of 188 metabolites in plasma samples from 130 healthy members of twin families (from the Netherlands Twin Register) at five time points during a modified 3 h hyperglycaemic clamp with glucose, GLP-1 and arginine stimulation. We validated our results in cohorts with OGTT data (n = 340) and epidemiological case–control studies of prevalent (n = 4925) and incident (n = 4277) diabetes. The data were analysed using regression models with adjustment for potential confounders.

Results

There were dynamic changes in metabolite levels in response to the different secretagogues. Furthermore, several fasting pairwise metabolite ratios were associated with one or multiple clamp-derived measures of insulin secretion (all p < 9.2 × 10^?7). These associations were significantly stronger compared with the individual metabolite components. One of the ratios, valine to phosphatidylcholine acyl-alkyl C32:2 (PC ae C32:2), in addition showed a directionally consistent positive association with OGTT-derived measures of insulin secretion and resistance (p ≤ 5.4 × 10^?3) and prevalent type 2 diabetes (OR_{Val_PC ae C32:2} 2.64 [β 0.97 ± 0.09], p = 1.0 × 10^?27). Furthermore, Val_PC ae C32:2 predicted incident diabetes independent of established risk factors in two epidemiological cohort studies (HR_{Val_PC ae C32:2} 1.57 [β 0.45 ± 0.06]; p = 1.3 × 10^?15), leading to modest improvements in the receiver operating characteristics when added to a model containing a set of established risk factors in both cohorts (increases from 0.780 to 0.801 and from 0.862 to 0.865 respectively, when added to the model containing traditional risk factors + glucose).

Conclusions/interpretation

In this study we have shown that the Val_PC ae C32:2 metabolite ratio is associated with an increased risk of type 2 diabetes and measures of insulin secretion and resistance. The observed effects were stronger than that of the individual metabolites and independent of known risk factors.

     

Incisional hernia after surgery for colorectal cancer: a population-based register study

Background

Our knowledge on the incidence of incisional hernia and risk factors for developing incisional hernia following surgery for colorectal cancer is far from complete.

Methods

All procedures registered in the Swedish Colorectal Cancer Register (SCRCR) 2007–2013 were identified. Patients with comorbid disease diagnoses, registered at admissions and visits prior to the procedure and relevant to this study, were obtained from the National Patient Register (NPR). These diagnoses included cardiovascular disease, connective tissue disorders, liver cirrhosis, renal failure, diabetes, chronic obstructive lung disease and chronic inflammatory conditions. Data on occurrence of incisional hernias were obtained by combining data from the SCRCR and the NPR (International Classification of Diseases code).

Results

During 2007–2013, 39,984 procedures were registered in the SCRCR. After excluding laparoscopic procedures, procedures repeated on the same patient, procedures with concomitant liver resection and procedures without laparotomy, 28,913 cases remained for analysis. Five years after surgery, the cumulative incidence of incisional hernia was 5.3%. In multivariate proportional hazard analysis, significantly increased risk for incisional hernia was found for the male gender (hazard ratio [HR] 1.40, 95% confidence interval [CI] 1.21–1.62), operation time exceeding 180 min (HR 1.25, CI 1.08–1.45), body mass index (BMI) >?30 (HR 1.78, CI 1.51–2.09), age <?70 years (HR 1.34, CI 1.16–1.56) and postoperative wound complication (HR 2.09, CI 1.70–2.58).

Discussion

Men, patients younger than 70 years and patients with BMI?>?30 face a higher risk for incisional hernia. The risk is also increased in cases where the procedure takes longer than 3 h or where postoperative wound complications occur. These patients will benefit from measures aimed at preventing the development of incisional hernia.

     

Universal fresh frozen plasma (Uniplas): a safe product in open-heart surgery

Objective To test the tolerability and safety of the universal plasma Uniplas [solvent/detergent (SD)-treated plasma], infused regardless of the patient's blood group.Design Prospective, parallel group, controlled and observer-blinded study, randomized with respect to patients requiring plasma transfusion.Setting Cardiothoracic operating room and ICU in a university hospital.Patients Eighty-four patients undergoing open-heart surgery comparing three parallel treatment groups and one control group.Interventions The Uniplas treatment group was subdivided into patients with blood group A, B or AB, and group O. The treatment group receiving Octaplas of type AB, was not subdivided. Patients who did not require any plasma transfusion served as control.Measurements Complement activation (C3bc, TCC), direct antiglobulin test (DAT) and other immunohaematological tests, tests for haemolysis, and relevant clinical observations during treatment phase. Blood samples were collected again after 6 months for evaluation of viral safety.Results Of the 84 patients, 29 served as control group. Uniplas was transfused in 36 of the patients (1–23 units). Octaplas was transfused in 19 patients (1–11 units). During the study no clinical adverse events related to plasma transfusion were observed. The degree of complement activation C3bc and TCC, a recommended test for biocompatibility, did not show any increased activation after Uniplas or Octaplas transfusion. No haemolytic reactions, positive DAT-tests or viral transmissions were observed after Uniplas transfusion.Conclusion In open-heart surgery, Uniplas, which can be transfused regardless of a patient's blood group, was well-tolerated and gave no adverse drug reactions.     

Additional ST-segment elevation during thrombolytic therapy in patients with acute ST-elevation myocardial infarction: impact on myocardial salvage and final infarct size

The aim of the study was to investigate the clinical significance of additional ST-segment elevation that occurs during thrombolytic therapy. Therefore, we classified 153 patients with a first acute myocardial infarction (MI) into two groups: Group A, 55 patients with additional ST-segment elevation > or = 1 mm above the initial ST elevation during thrombolytic therapy and Group B, 98 patients without this electrocardiographic pattern. Among the patients with anterior MI, Group A (n = 33) had no reduction from ST-predicted to final QRS-estimated infarct size (+12% versus -27%; p = 0.0005) and a larger final infarct size (QRS-score: 18% versus 12%; p = 0.0002) than Group B (n = 41). Among the patients with inferior MI, Group A (n = 22) had a smaller reduction from ST-predicted to final QRS-estimated infarct size (-30% versus -53%; p = 0.03) and a larger final infarct size (QRS-score: 15% versus 9%; p = 0.03) than Group B (n = 57). The area under the curve (AUC) of CK and CK-MB was higher in patients from Group A compared with those from Group B (anterior MI: AUC-CK: 22,048 versus 19,490 U.h.l-1; p = 0.07; AUC-MB: 2227 versus 2016 U.h.l-1; p = 0.11; inferior MI: AUC-CK: 17,206 versus 11,004 U.h.l-1; p = 0.01; AUC-MB: 2193 versus 1046 U.h.l-1; p = 0.007). Both global left ventricular function and ST-segment elevation resolution were significantly better in Group B. Two and three vessel disease was observed more frequently in Group A. Additional ST-segment elevation during thrombolytic therapy suggests reduced myocardial salvage by thrombolytic therapy and thus may result in larger final infarct size.