The conserved and divergent roles of Prdm3 and Prdm16 in zebrafish and mouse craniofacial development.

The formation of the craniofacial skeleton is a highly dynamic process that requires proper orchestration of various cellular processes in cranial neural crest cell (cNCC) development, including cell migration, proliferation, differentiation, polarity and cell death. Alterations that occur during cNCC development result in congenital birth defects and craniofacial abnormalities such as cleft lip with or without cleft palate. While the gene regulatory networks facilitating neural crest development have been extensively studied, the epigenetic mechanisms by which these pathways are activated or repressed in a temporal and spatially regulated manner remain largely unknown. Chromatin modifiers can precisely modify gene expression through a variety of mechanisms including histone modifications such as methylation. Here, we investigated the role of two members of the PRDM (Positive regulatory domain) histone methyltransferase family, Prdm3 and Prdm16 in craniofacial development using genetic models in zebrafish and mice. Loss of prdm3 or prdm16 in zebrafish causes craniofacial defects including hypoplasia of the craniofacial cartilage elements, undefined posterior ceratobranchials, and decreased mineralization of the parasphenoid. In mice, while conditional loss of Prdm3 in the early embryo proper causes mid-gestation lethality, loss of Prdm16 caused craniofacial defects including anterior mandibular hypoplasia, clefting in the secondary palate and severe middle ear defects. In zebrafish, prdm3 and prdm16 compensate for each other as well as a third Prdm family member, prdm1a. Combinatorial loss of prdm1a, prdm3, and prdm16 alleles results in severe hypoplasia of the anterior cartilage elements, abnormal formation of the jaw joint, complete loss of the posterior ceratobranchials, and clefting of the ethmoid plate. We further determined that loss of prdm3 and prdm16 reduces methylation of histone 3 lysine 9 (repression) and histone 3 lysine 4 (activation) in zebrafish. In mice, loss of Prdm16 significantly decreased histone 3 lysine 9 methylation in the palatal shelves but surprisingly did not change histone 3 lysine 4 methylation. Taken together, Prdm3 and Prdm16 play an important role in craniofacial development by maintaining temporal and spatial regulation of gene regulatory networks necessary for proper cNCC development and these functions are both conserved and divergent across vertebrates.

Difference of preventing effects of G-CSF according to age in patients with malignant lymphoma: A nation-wide analysis in Japan.

INTRODUCTION: There has been no comprehensive analysis of the age-specific efficacy of G-CSF to prevent febrile neutropenia (FN). We evaluated factors associated with FN occurrence according to patient age in rituximab-cyclophosphamide-doxorubicin-vincristine-prednisolone (R-CHOP) treatment. METHODS: We retrospectively reviewed diffuse large B-cell lymphoma (DLBCL) patients aged ≥50 years, who underwent the first R-CHOP cycle between July 2010 and March 2017, using a Japanese inpatient database. Multivariable logistic regression analysis was performed to identify the factors associated with FN. RESULTS: A total of 16,399 patients with untreated DLBCL were identified. Primary prophylaxis with pegfilgrastim was significantly associated with the lower occurrence of FN (odds ratio: 0.71 [95% confidence interval: 0.51-0.99]). Subgroup analysis according to age was then performed. Although there was no significance, primary prophylaxis with pegfilgrastim tended to have a lower odds ratio for the occurrence of FN in patients aged 50-60 years (0.86 [0.39-1.89]) and 61-70 years (0.64 [0.36-1.13]). In patients aged 71-80 years, primary prophylaxis with pegfilgrastim was significantly associated with reduced FN occurrence (0.46 [0.26-0.80]). Notably, in patients aged >80 years, the use of pegfilgrastim tended to be associated with a rather higher occurrence of FN (1.55 [0.84-2.87]). CONCLUSIONS: Preventing effect of G-CSF may be limited in patients aged >80 years.

Primary prophylaxis with pegfilgrastim during the first cycle of R-CHOP to avoid reduction of dose intensity in elderly patients.

The long-term effects of pegfilgrastim administered in the first cycle of chemotherapy in day-to-day practice remain unclear. We retrospectively identified 114 patients aged ≥ 70 years with diffuse large B-cell lymphoma who received a rituximab-cyclophosphamide-doxorubicin-vincristine-prednisolone (R-CHOP) regimen in our institution. Twenty-six patients received pegfilgrastim (pegfilgrastim group); of the 88 patients scheduled to receive conventional granulocyte-colony stimulating factor (G-CSF) when their neutrophil count decreased (neut-adjusted-G group), conventional G-CSF was ultimately administered to 57. During the first cycle of R-CHOP, the incidence of febrile neutropenia was lower in the pegfilgrastim group than in the neut-adjusted-G group (0% vs. 18%, p = 0.020). Throughout all cycles, a higher proportion of patients exhibited sustained relative dose intensity (≥ 80%) in the pegfilgrastim group than in the neut-adjusted-G group (25% vs. 4.0%, p = 0.008). A lower proportion of patients received a reduced dose in the second cycle in the pegfilgrastim group than in the neut-adjusted-G group (0% vs. 10%, p = 0.116). Although the differences were not significant, the pegfilgrastim group showed higher progression-free survival and overall survival than the neut-adjusted-G group. Adequate prevention of febrile neutropenia using pegfilgrastim during the first cycle of R-CHOP may contribute to avoidance of dose intensity reduction in all cycles.

Primary prophylaxis with pegfilgrastim in patients with newly-diagnosed diffuse large B-cell lymphoma: propensity score and instrumental variable analyses.

The clinical impact of pegfilgrastim in day-to-day practice remains unclear. This study evaluated the effectiveness of pegfilgrastim compared with daily filgrastim in patients with DLBCL who received the first-cycle of R-CHOP treatment by using a Japanese national inpatient database. Patient characteristics were adjusted by using propensity-score matching and stabilized inverse probability of treatment weighting (IPTW). In 1295 propensity-score-matched pairs, the incidence of febrile neutropenia was significantly lower in the pegfilgrastim group (risk difference 6.1%, 95% CI 4.1%-8.1%) than in the filgrastim group. In the pegfilgrastim group, the length of hospital stay and the total costs were also significantly reduced (percent reduction 34% [95% CI: 31%-37%], percent reduction 12% [95% CI: 9%-15%], respectively). The stabilized IPTW showed comparable results. In day-to-day practice, the simple mode of pegfilgrastim administration may be advantageous.

Using patient-derived iPSCs to develop humanized mouse models for chronic myelomonocytic leukemia and therapeutic drug identification, including liposomal clodronate.

Chronic myelomonocytic leukemia (CMML) is an entity of myelodysplastic syndrome/myeloproliferative neoplasm. Although CMML can be cured with allogeneic stem cell transplantation, its prognosis is generally very poor due to the limited efficacy of chemotherapy and to the patient's age, which is usually not eligible for transplantation. Comprehensive analysis of CMML pathophysiology and the development of therapeutic agents have been limited partly due to the lack of cell lines in CMML and the limited developments of mouse models. After successfully establishing patient's derived disease-specific induced pluripotent stem cells (iPSCs) derived from a patient with CMML, we utilized these CMML-iPSCs to achieve hematopoietic re-differentiation in vitro, created a humanized CMML mouse model via teratomas, and developed a drug-testing system. The clinical characteristics of CMML were recapitulated following hematopoietic re-differentiation in vitro and a humanized CMML mouse model in vivo. The drug-testing system using CMML-iPSCs identified a MEK inhibitor, a Ras inhibitor, and liposomal clodronate as potential drugs for treating CMML. Clodronate is a drug commonly used as a bisphosphonate for osteoporosis. In this study, the liposomalization of clodronate enhanced its effectiveness in these assays, suggesting that this variation of clodronate may be adopted as a repositioned drug for CMML therapy.

Primary Retroperitoneal Tumor with Unexpected Gingival Involvement.

Retroperitoneal tumors present diagnostic challenges, although a definitive diagnosis can be established based on a histopathological analysis. We herein report the case of a 62-year-old woman with a massive retroperitoneal tumor who was referred to our department for surgery. Although we initially planned to perform an incisional biopsy, we unexpectedly detected gingival swelling, and a gingival biopsy subsequently confirmed a pathological diagnosis of Burkitt's lymphoma (BL). We successfully avoided the use of more invasive diagnostic procedures and were able to promptly initiate chemotherapy. Obtaining an immediate pathological diagnosis is essential for providing successful treatment in such cases, as the disease is potentially curable with chemotherapy. BL should therefore be considered in the differential diagnosis of massive retroperitoneal tumors, highlighting the importance of routine systemic screening.

p130Cas, Crk-associated substrate, plays important roles in osteoclastic bone resorption.

p130Cas, Crk-associated substrate (Cas), is an adaptor/scaffold protein that plays a central role in actin cytoskeletal reorganization. We previously reported that p130Cas is not tyrosine-phosphorylated in osteoclasts derived from Src-deficient mice, which are congenitally osteopetrotic, suggesting that p130Cas serves as a downstream molecule of c-Src and is involved in osteoclastic bone resorption. However, the physiological role of p130Cas in osteoclasts has not yet been confirmed because the p130Cas-deficient mice displayed embryonic lethality. Osteoclast-specific p130Cas conditional knockout (p130Cas(ΔOCL-) ) mice exhibit a high bone mass phenotype caused by defect in multinucleation and cytoskeleton organization causing bone resorption deficiency. Bone marrow cells from p130Cas(ΔOCL-) mice were able to differentiate into osteoclasts and wild-type cells in vitro. However, osteoclasts from p130Cas(ΔOCL-) mice failed to form actin rings and resorb pits on dentine slices. Although the initial events of osteoclast attachment, such as ß3-integrin or Src phosphorylation, were intact, the Rac1 activity that organizes the actin cytoskeleton was reduced, and its distribution was disrupted in p130Cas(ΔOCL-) osteoclasts. Dedicator of cytokinesis 5 (Dock5), a Rho family guanine nucleotide exchanger, failed to associate with Src or Pyk2 in osteoclasts in the absence of p130Cas. These results strongly indicate that p130Cas plays pivotal roles in osteoclastic bone resorption.