A novel magnetic resonance-based method to measure gene expression in living cells

In unicellular and multicellular eukaryotes, elaborate gene regulatory mechanisms facilitate a broad range of biological processes from cell division to morphological differentiation. In order to fully understand the gene regulatory networks involved in these biological processes, the spatial and temporal patterns of expression of many thousands of genes will need to be determined in real time in living organisms. Currently available techniques are not sufficient to achieve this goal; however, novel methods based on magnetic resonance (MR) imaging may be particularly useful for sensitive detection of gene expression in opaque tissues. This report describes a novel reporter gene system that monitors gene expression dynamically and quantitatively, in yeast cells, by measuring the accumulation of inorganic polyphosphate (polyP) using MR spectroscopy (MRS) or MR spectroscopic imaging (MRI). Because this system is completely non-invasive and does not require exogenous substrates, it is a powerful tool for studying gene expression in multicellular organisms, as well

Application of modified shrinking field radiation in RT-DeVIC chemoradiotherapy for treating localized extranodal natural killer/T-cell lymphoma

　Concurrent chemoradiotherapy (CRT) is the recommended treatment for localized extranodal natural killer/T-cell lymphoma, nasal type (ENKL). In 2009, the Japan Clinical Oncology Group first documented the safety and efficacy of a regimen involving radiotherapy (RT) plus dexamethasone, etoposide, ifosfamide, and carboplatin (DeVIC) in their phase I/II trials (JCOG0211 study). The application of this regimen has drastically improved outcomes of patients with localized ENKL. In 2013, the current guidelines were made to the cost in JCOG0211 study.　We retrospectively investigated the outcomes of three patients who received CRT for stage localized ENKL at the Kawasaki Medical School Hospital between August 2007 and March 2011. Our CRT protocol differed from that used in the JCOG0211 study as we used a different shrinking field RT method. A recent report on shrinking or extended-field RT raised questions regarding which fields are appropriate. Thus, we compared our clinical results with those of the JCOG0211 study and analyzed the effect of the differences in field size on clinical results. The median follow-up of the three patients in the present study was 9 months (range, 5-106 months), two and one of whom achieved complete and partial responses, respectively. Regarding adverse events, no severe acute side effects (e.g., mucositis) higher than Grade 4 were observed.　We reviewed cases and the JCOG0211 study which we experienced in the past about fields of the RT. The present study described our experiences with three patients receiving shrinking field RT

SLPI is a critical mediator that controls PTH-induced bone formation

Osteoclastic bone resorption and osteoblastic bone formation/replenishment are closely coupled in bone metabolism. Anabolic parathyroid hormone (PTH), which is commonly used for treating osteoporosis, shifts the balance from osteoclastic to osteoblastic, although it is unclear how these cells are coordinately regulated by PTH. Here, we identify a serine protease inhibitor, secretory leukocyte protease inhibitor (SLPI), as a critical mediator that is involved in the PTH-mediated shift to the osteoblastic phase. Slpi is highly upregulated in osteoblasts by PTH, while genetic ablation of Slpi severely impairs PTH-induced bone formation. Slpi induction in osteoblasts enhances its differentiation, and increases osteoblast–osteoclast contact, thereby suppressing osteoclastic function. Intravital bone imaging reveals that the PTH-mediated association between osteoblasts and osteoclasts is disrupted in the absence of SLPI. Collectively, these results demonstrate that SLPI regulates the communication between osteoblasts and osteoclasts to promote PTH-induced bone anabolism.Morimoto A., Kikuta J., Nishikawa K., et al. SLPI is a critical mediator that controls PTH-induced bone formation. Nature Communications 12, 2136 (2021); https://doi.org/10.1038/s41467-021-22402-x

Oxygen functional groups on MWCNT surface as critical factor Boosting T-2 relaxation rate of water protons: towards improved CNT-based contrast agents

Purpose: Salicyl (Sal) – among other oxygen functionalities – multi-walled carbon nanotubes (MWCNTs) and their nanohybrids are investigated as promising contrast agents (CA) in magnetic resonance imaging (MRI) or drug delivery platforms, due to their unique properties. The preliminary results and the literature reports were the motivation to endow high r2 relaxivities, excellent dispersibility in water, and biocompatibility to superparamagnetic MWCNTs nanohybrids. It was hypothesized that these goals could be achieved by, not described in the literature yet, two-stage oxygen functionalization of MWCNTs. Results: Two structurally different MWCNT materials differing in diameters (44 and 12 nm) and the iron content (4.7% and 0.5%) are studied toward the functionalization effect on the T2 relaxometric properties. MWCNT oxidation is typically the first step of functionalization resulting in “first generation” oxygen functional groups (OFGs) on the surface. Until now, the impact of OFGs on the relaxivity of MWCNT was not truly recognized, but this study sheds light on this issue. By follow-up functionalization of oxidized MWCNT with 4-azidosalicylic acid through [2+1] cycloaddition of the corresponding nitrene, “second generation” of oxygen functional groups is grafted onto the nanohybrid, ie, Sal functionality. Conclusion: The introduced OFGs are responsible for an almost 30% increase in the relaxivity, which leads to remarkable r2 relaxivity of 951 mM−1s−1 (419 (mg/mL)−1s−1), the unprecedented value reported to date for this class of CAs. Also, the resulting nanohybrids express low cytotoxicity and superb diffusion after subcutaneous injection to a mouse

Osteoblast-derived vesicles induce a switch from bone-formation to bone-resorption in vivo

Bone metabolism is regulated by the cooperative activity between bone-forming osteoblasts and bone-resorbing osteoclasts. However, the mechanisms mediating the switch between the osteoblastic and osteoclastic phases have not been fully elucidated. Here, we identify a specific subset of mature osteoblast-derived extracellular vesicles that inhibit bone formation and enhance osteoclastogenesis. Intravital imaging reveals that mature osteoblasts secrete and capture extracellular vesicles, referred to as small osteoblast vesicles (SOVs). Co-culture experiments demonstrate that SOVs suppress osteoblast differentiation and enhance the expression of receptor activator of NF-κB ligand, thereby inducing osteoclast differentiation. We also elucidate that the SOV-enriched microRNA miR-143 inhibits Runt-related transcription factor 2, a master regulator of osteoblastogenesis, by targeting the mRNA expression of its dimerization partner, core-binding factor β. In summary, we identify SOVs as a mode of cell-to-cell communication, controlling the dynamic transition from bone-forming to bone-resorbing phases in vivo.Uenaka M., Yamashita E., Kikuta J., et al. Osteoblast-derived vesicles induce a switch from bone-formation to bone-resorption in vivo. Nature Communications 13, 1066 (2022); https://doi.org/10.1038/s41467-022-28673-2

成人発症の難治性胞巣型横紋筋肉腫に対する Vincristine Irinotecan Temozolomide 療法を用いた治療経験

　成人発症の胞巣型横紋筋肉腫は，まれであり，再発しやすく予後が悪いと言われている．さまざまな化学療法が試されているが効果的な報告は少ない．我々は，難治性胞巣型横紋筋肉腫に対してVincristine Irinotecan Temozolomide（VITA）療法を施行し，長期完全奏効（Complete Response：CR）を維持している症例を経験したため報告する．症例は20歳代の男性で，トルコ鞍斜台に腫瘍を認め，摘出生検を施行し胞巣型横紋筋肉腫と診断された．残存腫瘤に対して放射線治療を施行し，CT 検査で病変の消失を確認した．術後３か月後に右頸部リンパ節腫大が出現し，リンパ節郭清術を施行した．その２か月後に左頸部リンパ節腫大が出現したため，Childrens Oncology Group ARST0431レジメン（VI 療法とVDC/IE 交代療法およびVAC 療法によるブロックから構成される計54週間の治療）を施行し，PET/CT でFDG 集積の消失を確認し，CT でもリンパ節腫大病変は消失した．しかし，１年後に左頸部リンパ節腫大が再度出現．再発と判断し，VITA 療法を開始した．６コース施行しCT にてCR を確認した．以後，外来で経過観察中でありCR を維持している．難治性胞巣型横紋筋肉腫に対してVITA 療法は有用であると考えられ，治療法の選択枝の一つとして考慮すべきである．　Adult onset alveolar rhabdomyosarcoma is rare, but recurrence is common and prognosis is poor. Various types of chemotherapy regimens have been attempted, but few studies have reported information on efficacy. Here, we report our experience with a patient who received Vincristine Irinotecan Temozolomide (VITA) therapy and in whom long-term (complete response: CR) was maintained. The patient was a 20-year-old man who developed alveolar rhabdomyosarcoma in the clivus of the sella turcica. Following enucleation and postoperative radiotherapy, lesion disappeared by CT was achieved. However, right cervical lymphadenopathy was soon apparent, and a lymphadenectomy was performed. Because left cervical lymphadenopathy was apparent after 2 months, the Children\u27s Oncology Group ARST0431 regimen (54 weeks of therapy: blocks of therapy with VI, interval compression with VDC/IE and VAC) was initiated, negative PET imaging and lesion disappeared by CT was achieved. However, reappearance of left cervical lymphadenopathy was noted after 1 year. Recurrence was diagnosed in the patient, and VITA therapy was initiated again. CR was achieved after 6 courses, and subsequent outpatient follow-up has revealed that CR has been maintained. Hence, VITA therapy may be useful for treatment-resistant alveolar rhabdomyosarcoma and should be considered as a treatment option

Multistep Ion Channel Remodeling and Lethal Arrhythmia Precede Heart Failure in a Mouse Model of Inherited Dilated Cardiomyopathy

Background: Patients with inherited dilated cardiomyopathy (DCM) frequently die with severe heart failure (HF) or die suddenly with arrhythmias, although these symptoms are not always observed at birth. It remains unclear how and when HF and arrhythmogenic changes develop in these DCM mutation carriers. In order to address this issue, properties of the myocardium and underlying gene expressions were studied using a knock-in mouse model of human inherited DCM caused by a deletion mutation DK210 in cardiac troponinT. Methodology/Principal Findings: By 1 month, DCM mice had already enlarged hearts, but showed no symptoms of HF and a much lower mortality than at 2 months or later. At around 2 months, some would die suddenly with no clear symptoms of HF, whereas at 3 months, many of the survivors showed evident symptoms of HF. In isolated left ventricular myocardium (LV) from 2 month-mice, spontaneous activity frequently occurred and action potential duration (APD) was prolonged. Transient outward (Ito) and ultrarapid delayed rectifier K + (IKur) currents were significantly reduced in DCM myocytes. Correspondingly, down-regulation of Kv4.2, Kv1.5 and KChIP2 was evident in mRNA and protein levels. In LVs at 3-months, more frequent spontaneous activity, greater prolongation of APD and further down-regulation in above K + channels were observed. At 1 month, in contrast, infrequent spontaneous activity and down-regulation of Kv4.2, but not Kv1.5 or KChIP2, were observed

胸水細胞診で形質細胞腫が疑われた血管免疫芽球性Ｔ細胞リンパ腫

血管免疫芽球性Ｔ細胞リンパ腫（angioimmunoblastic T-cell lymphoma: AITL）は新WHO分類において末梢Ｔ細胞 / NK 細胞腫瘍に分類されているＴ細胞性腫瘍である．その臨床像は，全身リンパ節腫大，肝脾腫，発熱，多クローン性高γ グロブリン血症など多様な症状を呈することが知られている．今回，我々は胸水細胞診で形質細胞腫が疑われたAITL を経験したので報告する．症例は80歳代の女性．近医にて気管支喘息治療中に，喘息症状が悪化し，全身の皮疹が出現．両側胸水貯留，CRP 高値が出現したため，精査治療目的で当院紹介となった．血液検査で貧血を認め，末梢血に形質細胞様の異型リンパ球を10％認めた．胸水には大小不同のCD138陽性形質細胞を多数認め細胞診で形質細胞腫が疑われたが，胸水セルブロックではκ・λ の軽鎖制限を認めなかった．骨髄検査では，形質細胞の増加を認めず赤芽球癆の状態であった．皮下腫瘤を生検した結果，AITL と診断した．AITL は，腫瘍細胞が直接的・間接的にサイトカインを産生し，それに起因した多彩な臨床像を呈する．そのため，AITL は反応性に形質細胞の増加を伴うことが多く，本症例は，反応性に胸水中に形質細胞の増加を伴ったと考えられた．また，AITL は赤芽球癆を合併することも報告されている．AITL では，反応性の形質細胞増多を伴う胸水貯留や赤芽球癆をきたす場合があることに注意すべきである．Angioimmunoblastic T cell lymphoma (AITL) is a T cell-related tumor that is classified as a peripheral T cell/natural killer cell tumor according to the new World Health Organization classification. AITL shows various clinical features owing to the cytokines produced directly or indirectly by tumor cells and includes a variety of symptoms, such as general lymphadenopathy, hepatosplenomegaly, fever, and polyclonal hypergammaglobulinemia. AITL is often accompanied by reactive plasmacytosis, and it has been reported that AITL can be complicated by pure red cell aplasia. Here, we report an 80-year-old woman with AITL who was suspected to have a plasma cell tumor by cytological diagnosis of hydrothorax. The patient presented with exacerbated asthmatic symptoms as well as exanthema over her entire body. Moreover, during treatment for bronchial asthma at a local doctor’s clinic, hydrothorax in both lungs and high C-reactive protein levels were observed. She was referred to our hospital for detailed examination and treatment. Blood test results revealed anemia as well as a high proportion of plasma cell-like atypical lymphocytes in the peripheral blood. Specimens of the hydrothorax also contained CD138-positive plasma cells of varying sizes; however, there was no evidence of deviation in light chain limitation. We did not notice elevated plasma cell counts, and the patient was considered to have pure red cell aplasia based on the results of the marrow examination. However, we noted a subcutaneous mass under her shoulder blade. An excisional biopsy was performed, and she was diagnosed with AITL. The patient was considered to have hydrothorax with plasmacytosis as a reaction to AITL. As seen in our case, AITL may cause pleural effusions along with reactive plasmacytosis and pure red cell aplasia