p94, a muscle-specific member of calpain family, is unique in that it undergoes rapid and exhaustive autolysis with a half-life of less than 1 h resulting in its disappearance from muscle. Recently, p94 was shown to be responsible for limb girdle muscular dystrophy type 2A. To elucidate the muscular proteolytic system mediated by p94 and to solve the mystery of its unusually rapid autolysis, we searched for p94-binding proteins by the two-hybrid system. Although calpain small subunit plays a crucial role for regulation of ubiquitous calpains, it did not associate with p94. After a screening of skeletal muscle library, connectin (or titin), a gigantic filamentous protein spanning the M-to Z-lines of muscle sarcomere, was found to bind to p94 through a p94-specific region, IS2. The connectin-insoluble fraction of washed myofibrils contained full-length intact p94, suggesting that connectin regulates p94 activity.Proteolysis in cytosol is a key reaction to modulate various intracellular protein functions such as signal transduction, protein turnover, and cell structure. Calpain, Ca 2ϩ -dependent cysteine proteinase (EC 3.4.22.17), is one of the major intracellular proteinases known as interacting various protein kinases, transcription factors, and cytoskeletal proteins (1-5). Ubiquitous -and m-calpains, dimers of a large catalytic (CL 1 (6) and mCL (7), respectively) and small regulatory (30K (8)) subunit. Recently, we found that the ubiquitous calpain large subunit monomer can express full proteolytic activity, and that 30K dissociates from the large subunit upon activation by Ca 2ϩ (9, 10). In other words, 30K together with calpastatin, a specific proteinaceous inhibitor for calpain, play pivotal roles in regulation of calpain activity.p94 is a muscle-specific member of the calpain large subunit family, and distinct not only from the other members but also from other proteases in that it autolyzes very rapidly and extensively leading to almost complete disappearance right after translation even in the presence of EGTA and leupeptin as observed in vitro (11,12). Ubiquitous calpains as well as many other proteases also undergo autolysis at the NH 2 terminus, but only to a limited extent. Quite recently, p94 was identified as responsible for limb girdle muscular dystrophy type 2A (LGMD2A), the first demonstration of the involvement of an enzyme in muscle dystrophy (13). To elucidate physiological meaning of this exhaustive autolysis and the molecular mechanism connecting LGMD2A and p94 function, it is important to clarify the substrates of p94 and the manner to regulate the proteolytic activity of p94.30K is the first candidate to bind to and regulate p94, since the calmodulin-like Ca 2ϩ -binding domains of CL and mCL (see Fig. 2), which are the binding sites for 30K, are highly homologous to p94 (5). Analysis of p94 at the protein level, however, is very difficult because of the extremely rapid autolysis, and, thus, we examined using the yeast two-hybrid system (14). As a result, 30K was revealed not to bind to p94...

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Among diffuse gliomas, oligodendrogliomas show relatively better prognosis, respond well to radiotherapy and chemotherapy, and seldom progress to very aggressive tumors. To elucidate the genetic and epigenetic background for such behavior and tumor evolution during tumor relapse, we comparatively analyzed 12 pairs of primary and recurrent oligodendrogliomas with 1p/19q-codeletion. Initial treatment for these patients was mostly chemotherapy alone. Temozolomide was used for 3, and procarbazine, nimustine and vincristine (PAV chemotherapy) were used for 7 patients. World Health Organization histological grade at recurrence was mostly stable; it was increased in 2, the same in 9, and decreased in 1 cases. Whole-exome sequencing demonstrated that the rate of shared mutation between the primary and recurrent tumors was relatively low, ranging from 3.2-57.9% (average, 33.3%), indicating a branched evolutionary pattern. The trunk alterations that existed throughout the course were restricted to IDH1 mutation, 1p/19q-codeletion, and TERT promoter mutation, and mutation of the known candidate tumor suppressor genes CIC and FUBP1 were not consistently observed between primary and recurrent tumors. Multiple sampling from different regions within a tumor showed marked intratumoral heterogeneity. Notably, in general, the number of mutations was not significantly different after recurrence, remaining under 100, and no hypermutator phenotype was observed. FUBP1 mutation, loss of chr. 9p21, and TCF12 mutation were among a few recurrent de novo alterations that were found at recurrence, indicating that these events were clonally selected at recurrence but were not enough to enhance malignancy. Genome-wide methylation status, measured by Illumina 450 K arrays, was stable between recurrence and the primary tumor. In summary, although oligodendroglioma displays marked mutational heterogeneity, histological malignant transformation accompanying events such as considerable increase in mutation number and epigenetic profile change were not observed at recurrence, indicating that noticeable temporal and spatial genetic heterogeneity in oligodendrogliomas does not result in rapid tumor progression.Electronic supplementary materialThe online version of this article (doi:10.1186/s40478-017-0422-z) contains supplementary material, which is available to authorized users.

A positive scan in pretransplantation fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) has been shown to be associated with a poor prognosis in patients with lymphoma undergoing highdose chemotherapy followed by autologous stem cell transplantation (ASCT). For those with a positive FDG-PET scan, treatment that includes allogeneic stem cell transplantation (allo-SCT) may be an alternative. However, it is uncertain whether allo-SCT can overcome a poor prognosis. Therefore, we conducted a retrospective analysis of 14 patients with lymphoma who had undergone FDG-PET scan within one month before allo-SCT at our institution. Eleven patients were FDG-PET-positive and three were negative. With a median follow-up of 17 months (range: 6-44) after allo-SCT, the cumulative incidence of progression was 29.3% in FDG-PET-positive patients and 0% in the FDG-PET-negative patients. Four of the 11 patients who had post-transplantation FDG-PET showed FDG-avid lesions on the first post-transplantation scan. In two of the four, regression of the lesions was observed during the scheduled reduction of immunosuppressant without donor lymphocyte infusion and remained without progression at the last follow-up (34 and 8 months). Durable responses after allo-SCT, at least with conventional conditioning regimens, can be expected in patients with FDG-PET-positive lesions before transplantation. Thus, conventional allo-SCT could be an attractive modality compared to ASCT for patients with positive FDG-PET after the completion of conventional salvage chemotherapy, and particularly for patients with T and NK-cell lymphomas. Am. J. Hematol. 83:477-481, 2008. V

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