Daratumumab­resistant multiple myeloma with extramedullary disease successfully treated with combination elotuzumab, pomalidomide and dexamethasone: A case report.

Despite the emergence of monoclonal antibodies, the prognosis of patients with multiple myeloma (MM) with extramedullary disease remains poor. The present report describes a rare case of daratumumab-refractory MM that was successfully treated with elotuzumab, pomalidomide and dexamethasone. A 66-year-old male patient diagnosed with MM was treated with bortezomib, lenalidomide and dexamethasone, followed by high-dose chemotherapy and autologous stem cell transplantation. Thereafter, the patient was treated with lenalidomide and dexamethasone as maintenance therapy. This was changed to daratumumab, bortezomib and dexamethasone when new paraskeletal lesions were identified, resulting in marked tumor shrinkage. After 15 months, an increase in serum monoclonal protein levels, development of a skeletal lesion in the right second rib and extramedullary disease of the right thoracic mediastinal lymph nodes were noted. Treatment with elotuzumab, pomalidomide and dexamethasone (EPd) resulted in expeditious symptomatic improvement and regression of the lesions. Notably, during daratumumab, bortezomib and dexamethasone treatment, lymphocyte counts gradually increased to a level at which elotuzumab was sufficiently effective. EPd might be a promising strategy for the treatment of patients with relapsed extramedullary MM while on daratumumab treatment.

Bile duct MALT lymphoma diagnosed with direct cholangioscopy: a case report.

Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) extremely rarely arise in extrahepatic biliary tract. Here, we report a case of bile duct MALT lymphoma diagnosed with direct cholangioscopy. The patient was an 80-year-old female with history of esophageal cancer, and had been occasionally treated with balloon dilatation for anastomotic stricture. She was referred to our hospital for treatment of choledocholithiasis. Since transesophageal endoscope insertion was impossible, stone extraction by transjejunal approach was performed. When gastroduodenoscope was directly inserted to the bile duct (direct cholangioscopy), accidentally two flat lesions with development of large atypical vessels in hilar region were noted. Biopsy revealed diffuse infiltration of CD20 positive small- to medium-sized atypical lymphocytes. A diagnosis of bile duct MALT lymphoma was made. The patient underwent eight courses of chemotherapy with rituximab alone, with no evident complications. Although biliary tract MALT lymphoma is rare, advances in cholangioscopy may promote encounter with such lesions. Accumulation of endoscopic figures of biliary tract MALT lymphoma is required.

Localized astrogenesis regulates gyrification of the cerebral cortex.

The development and evolution of mammalian higher cognition are represented by gyrification of the laminar cerebral cortex and astrocyte development, but their mechanisms and interrelationships remain unknown. Here, we show that localized astrogenesis plays an important role in gyri formation in the gyrencephalic cerebral cortex. In functional genetic experiments, we show that reducing astrocyte number prevents gyri formation in the ferret cortex, while increasing astrocyte number in mice, which do not have cortical folds, can induce gyrus-like protrusions. Morphometric analyses demonstrate that the vertical expansion of deep pallial regions achieved by localized astrogenesis is crucial for gyri formation. Furthermore, our findings suggest that localized astrogenesis by a positive feedback loop of FGF signaling is an important mechanism underlying cortical folding in gyrencephalic mammalian brains. Our findings reveal both the cellular mechanisms and the mechanical principle of gyrification in the mammalian brain.

Glial cell type-specific gene expression in the mouse cerebrum using the piggyBac system and in utero electroporation.

Glial cells such as astrocytes and oligodendrocytes play crucial roles in the central nervous system. To investigate the molecular mechanisms underlying the development and the biological functions of glial cells, simple and rapid techniques for glial cell-specific genetic manipulation in the mouse cerebrum would be valuable. Here we uncovered that the Gfa2 promoter is suitable for selective gene expression in astrocytes when used with the piggyBac system and in utero electroporation. In contrast, the Blbp promoter, which has been used to induce astrocyte-specific gene expression in transgenic mice, did not result in astrocyte-specific gene expression. We also identified the Plp1 and Mbp promoters could be used with the piggyBac system and in utero electroporation to induce selective gene expression in oligodendrocytes. Furthermore, using our technique, neuron-astrocyte or neuron-oligodendrocyte interactions can be visualized by labeling neurons, astrocytes and oligodendrocytes differentially. Our study provides a fundamental basis for specific transgene expression in astrocytes and/or oligodendrocytes in the mouse cerebrum.