Hypermethylation of the calcitonin gene in acute lymphoblastic leukaemia is associated with unfavourable clinical outcome

We analysed calcitonin (CALC1) gene hypermethylation using semiquantitative differential polymerase chain reaction in 105 patients with adult (n = 49) and childhood (n = 56) acute lymphoblastic leukaemia (ALL), and studied the association of CALC1 hypermethylation with clinical presentation features and disease outcome. We also investigated the possible relationship between CALC1 methylation status and expression of the cell cycle inhibitor gene p57KIP2. We observed CALC1 hypermethylation in bone marrow cells from 43% (45 out of 105) of ALL patients. Clinical, molecular and laboratory features did not differ significantly between hypermethylated and hypomethylated patients, only T-cell lineage was associated with hypermethylation (14% vs. 47%, P = 0025). Complete remission rate was similar in both groups although hypermethylated patients had a higher relapse rate (68% vs. 19%, P < 0.00001) and mortality rate (55% vs. 36%, P = 0.06) than hypomethylated patients. Estimated disease-free survival (DFS) at 6 years was 66.1% for hypomethylated patients and 5.3% for hypermethylated patients (P < 0,00001). Multivariate analysis from potential prognostic factors demonstrated that CALC1 methylation status was an independent prognostic factor in predicting DFS (P = 0.0001). Separate analysis of adult and childhood ALL patients showed similar results to the whole series. In addition, hypermethylated patients showed downregulation of p57KIP2 expression. Our results suggest that CALC1 gene hypermethylation is associated with an enhanced risk of relapse independently of known poor-prognostic factors and we describe, for the first time, a possible implication of the p57KIP2 gene in the genesis and prognosis of ALL.     

Cytotoxic effects of SMAC-mimetic compound LCL161 in head and neck cancer cell lines

Objectives

Head and neck squamous cell carcinoma (HNSCC) is one of the most common tumor entities worldwide. Unfortunately, recent drug developments in other fields of oncology have yielded no efficacy in the treatment of oral squamous cell carcinoma. As a new starting point, we investigated the impact of Fas ligand (FasL) and the SMAC-mimetic compound LCL161 in mono- and combination treatment in HNSCC cell lines.

Methods

Five different cell lines of HNSCC were treated with FasL and LCL161 in mono- and combination treatment. Cytotoxicity was measured via a crystal violet assay. The cell lines were characterized for CD95 (FasL receptor) expression via flow cytometry. The degradation of cellular inhibitor of apoptosis protein 1 (cIAP1) was detected via Western blot.

Results

Incubation with FasL led to a significant decrease in three out of five cell lines. Combination treatment with LCL161 enhanced cytotoxicity significantly. Two cell lines were FasL resistant, but one of them could be resensitized with LCL161. In all cell lines, Western blot analysis showed degradation of cIAP1 after LCL161 application. However, one cell line showed only minor vulnerability to the FasL and LCL161 combination.

Conclusion

This is the first study investigating combination treatment of FasL and LCL161 in head and neck cancer cell lines. Pro-apoptotic effects of the combination were detected in the majority of the cell lines. Interestingly, one of two FasL-resistant cell lines was sensitive to the combination therapy with FasL and LCL161.

Clinical relevance

SMAC-mimetic compounds show promising results in the treatment of other tumor entities in vitro and might be useful drugs to improve HNSCC therapy.

     

Rational design of aggregation-resistant bioactive peptides: reengineering human calcitonin

A high propensity to aggregate into intractable deposits is a common problem limiting the production and use of many peptides and proteins in a wide range of biotechnological and pharmaceutical applications. Many therapeutic polypeptides are frequently abandoned at an early stage in their development because of problems with stability and aggregation. It has been shown recently that parameters describing the physicochemical properties of polypeptides can be used as predictors of protein aggregation. Here we demonstrate that these and similar tools can be applied to the rational redesign of bioactive molecules with a significantly reduced aggregation propensity without loss of physiological activity. This strategy has been exemplified by designing variants of the hormone calcitonin that show a significantly reduced aggregation propensity, yet maintain, or even increase, their potency when compared to the current therapeutic forms. The results suggest that this approach could be used successfully to enhance the solubility and efficacy of a wide range of other peptide and protein therapeutics.     

Association of albuminuria with systolic and diastolic left ventricular dysfunction in type 2 diabetes: the Strong Heart Study

OBJECTIVES: We sought to compare systolic and diastolic function in American Indians with diabetes mellitus (DM) based on albuminuria status. BACKGROUND: Albuminuria has been shown to predict cardiovascular disease (CVD) in populations with DM. However, the mechanism of the association of albuminuria and CVD is unclear. METHODS: We compared echo-derived indices of left ventricular (LV) systolic and diastolic function in three groups of American Indians with DM based on albuminuria status: I = no albuminuria (<30 mg albumin/g creatinine); II = microalbuminuria (30 to 300 mg/g); and III = macroalbuminuria (>300 mg/g). RESULTS: Group II and III were slightly older than Group I with no significant gender difference between groups. Systolic blood pressure increased and body mass index decreased from Group I to Group III. Left ventricular systolic function was lower in the groups with albuminuria with step-wise decreases in ejection fraction and stress-corrected midwall shortening (MWS) from Group I to Group III. Similar findings were noted in diastolic LV filling with lower mitral E/A ratios and longer deceleration times in groups with albuminuria. The proportion of participants with abnormal MWS and abnormal LV diastolic relaxation showed step-wise increases from no albuminuria to macroalbuminuria. In multivariate analysis, albuminuria status remained independently associated with both systolic and diastolic dysfunction after adjusting for age, gender, body mass index, systolic blood pressure, duration of diabetes, coronary artery disease, and LV mass. CONCLUSIONS: Albuminuria is independently associated with LV systolic and diastolic dysfunction in type 2 DM; this may explain in part the relationship of albuminuria to increased cardiovascular (CV) events in the DM population. Screening for albuminuria identifies individuals with high CV risk and possible cardiac dysfunction.     

Use of stentrievers in acute stroke: tips, tricks, and current results

Stentrievers are stent-like devices used in the treatment of acute ischemic stroke. They have demonstrated efficacy in restoring the intracranial blood flow with low procedural times. This article is a synopsis of the available devices and different techniques. An extensive review of the literature summarizing all the data that have been published demonstrating their clinical impact and complications is also presented.