Salinomycin Sensitizes Melanoma Spheroids Containing Slow-Cycling Cells to the Effects of Arsenic Trioxide

Recurrence after chemotherapy is a major cause of cancer mortality : subsets of tumor cells evade initial chemotherapy or radiotherapy and survive to re-propagate the tumor. To develop a novel therapeutic approach for melanoma, we applied a non-adhesive culture system which developed spheroids mimicking the properties of melanoma in vivo. Subsequently, spheroids involved cells exhibiting clonogenic and slow-cycling properties in addition to chemotherapeutic resistance to doxorubicin. Interestingly, while treatment of spheroids with either salinomycin or As_2O_3 showed limiting effects, a combinatorial treatment was markedly superior to single treatment with each drug. Thus, melanoma spheroids could be a new platform for studying melanoma biology and are likely to provide a clinically relevant target for the novel chemotherapy

A Method for Systematic Assessment of Intrinsically Disordered Protein Regions by NMR

Intrinsically disordered proteins (IDPs) that lack stable conformations and are highly flexible have attracted the attention of biologists. Therefore, the development of a systematic method to identify polypeptide regions that are unstructured in solution is important. We have designed an “indirect/reflected” detection system for evaluating the physicochemical properties of IDPs using nuclear magnetic resonance (NMR). This approach employs a “chimeric membrane protein”-based method using the thermostable membrane protein PH0471. This protein contains two domains, a transmembrane helical region and a C-terminal OB (oligonucleotide/oligosaccharide binding)-fold domain (named NfeDC domain), connected by a flexible linker. NMR signals of the OB-fold domain of detergent-solubilized PH0471 are observed because of the flexibility of the linker region. In this study, the linker region was substituted with target IDPs. Fifty-three candidates were selected using the prediction tool POODLE and 35 expression vectors were constructed. Subsequently, we obtained 15N-labeled chimeric PH0471 proteins with 25 IDPs as linkers. The NMR spectra allowed us to classify IDPs into three categories: flexible, moderately flexible, and inflexible. The inflexible IDPs contain membrane-associating or aggregation-prone sequences. This is the first attempt to use an indirect/reflected NMR method to evaluate IDPs and can verify the predictions derived from our computational tools

Transient Creatine Kinase Elevation Followed by Hypocomplementemia in a Case of Rotavirus Myositis

We report an infant case of rotavirus myositis, a rare complication of rotavirus infection. Complement levels of the patient were normal when serum creatine kinase (CK) level was at its peak and then decreased when the CK level became normalized. In a previous case report of rotavirus myositis, transient decrease of serum albumin, immunoglobulin, and complement levels was reported. The authors speculated that intravascular complement activation was caused by rotavirus and resulted in the pathogenesis of myositis, although complement levels at onset were not measured by the authors. In this report, however, we demonstrate that the complement activation of our patient is a result of, rather than the cause of, skeletal muscle damage

Case Report Transient Creatine Kinase Elevation Followed by Hypocomplementemia in a Case of Rotavirus Myositis

We report an infant case of rotavirus myositis, a rare complication of rotavirus infection. Complement levels of the patient were normal when serum creatine kinase (CK) level was at its peak and then decreased when the CK level became normalized. In a previous case report of rotavirus myositis, transient decrease of serum albumin, immunoglobulin, and complement levels was reported. The authors speculated that intravascular complement activation was caused by rotavirus and resulted in the pathogenesis of myositis, although complement levels at onset were not measured by the authors. In this report, however, we demonstrate that the complement activation of our patient is a result of, rather than the cause of, skeletal muscle damage

ENHANCED COLLAGEN FORMATION IN MICE WITH CONTROLLED RELEASE OF FROZEN-POOLED PLATELET-DERIVED FACTORS

Platelet-derived factors messenger to regulate a well-orchestrated and complex series of events involving cell-cell and cell-matrix interactions and play a key role during the various phases of the wound-repair process. To evaluate the effects of controlled release of platelet-derived factors, we performed the subcutaneous implantation of gelatin hydrogel loaded with frozen-pooled platelet-rich plasma into the back of mice. Consequently, a successful enhancement of collagen formation was observed at the subcutaneous tissues on day 14. The present study reveals that this novel therapeutic approach is hopeful to improve the recovery of healing-impaired cutaneous wound