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The successful generation of induced pluripotent stem cells (iPSCs) has significantly impacted many scientific fields. In the field of regenerative medicine, iPSC-derived somatic cells are expected to recover impaired organ functions through cell transplantation therapy. Subsequent studies using genetically engineered mouse models showed that somatic cells are also reprogrammable in vivo. Notably, cyclic expression of reprogramming factors, so-called partial reprogramming in vivo ameliorates cellular and physiological hallmarks of aging without inducing teratoma formation or premature death of animals. Subsequent studies provided evidence supporting the beneficial effects of partial reprogramming in various organs. Although in vivo reprogramming appears to be a promising strategy for tissue regeneration and rejuvenation, there remain unsolved issues that hinder its clinical application, including concerns regarding its safety, controllability, and unexpected detrimental effects. Here, we review the pathway that research of in vivo reprogramming has followed and discuss the future perspective as we look toward its clinical application in regenerative medicine.

The calcium carbonate (CaCO3) scale generated in water pipes and heat exchangers causes serious problems such as pipe blockage and corrosion. This study investigates the effect of the 4-to-10 μm-long and 350-to-700 nm centering-nucleus-wide ZnO tetrapod-like nanomaterials and polydimethylsiloxane composite (t-ZnO/PDMS) on deposition and polymorphism of CaCO3 crystals on the stainless-steel substrate. The results showed that the t-ZnO/PDMS coating inhibited CaCO3 depositions and represented an excellent antifouling coating. The weight-based inhibition efficiencies of CaCO3 deposition were up to 81.3% and 63.2% at 20 °C and 60 °C, respectively. The t-ZnO/PDMS coating also exhibited good inhibition in the presence of liquid flow. The inhibition is primarily because the very fine concave-convex microstructure of the t-ZnO/PDMS coated surface lowered the surface energy of the substrates, making it difficult for CaCO3 crystals to adhere to the surface. Also, metastable vaterite and aragonite precipitations were dominant in the t-ZnO/PDMS coated coupons at 20 °C and 60 °C, respectively, whereas the uncoated coupon exhibited calcite as the predominant polymorph in all the studied conditions. The t-ZnO/PDMS composite subject to the liquid flow made calcites distorted and framboidal vaterite aggregates, likely due to their mechanical effects. The inhibition of CaCO3 depositions is due to achieving hydrophobicity on substrate surfaces, changing preferential polymorph formation, and tailoring the morphology of the given polymorph by the t-ZnO/PDMS composite.

Objective: Endoscopic microvascular decompression (eMVD) for hemifacial spasm (HFS) clearly demonstrates the root entry zone (REZ) of the facial nerve with minimal invasiveness. The aim of this study was to identify the trajectory of the angled view under eMVD for HFS and to better understand the relevant anatomical landmarks using a virtual straight microscopic view on three-dimensional (3D) fusion images. Methods: Each 3D fusion image including arteries, veins, brainstem, cranial nerves, and skull was created using an image processing workstation. A trajectory of view under a 30° angled endoscope was defined as the angled view trajectory (AVT). To investigate the anatomy along the AVT, 3D fusion images were manually made consistent with the 30° endoscopic view, and a straight microscopic approach to obtain the same view as the endoscopic surgery was analyzed on 3D fusion images. Results: The 30° endoscopic view during eMVD visualized the lateral side of the pons, pontomedullary junction, REZ of the facial nerve, and offending arteries. The 30° endoscopic view correlated with 3D fusion images from the straight microscopic view obtained by the posterior petrosal approach after mastoidectomy with incision of the transition between the sigmoid sinus and jugular bulb. Conclusions: This 3D fusion image analysis revealed the AVT of eMVD for HFS. The present results explain how the angled endoscope can effectively visualize the REZ of the facial nerve without needing extensive skull base resection.

Background: Once the decision is made to treat the intracranial aneurysm, we should consider between two competing treatment options; open surgery or endovascular therapy. The rationale underlying the choice of treatment modality is usually unclear, as there is little good quality evidence available. Methods: We discuss here the patient, risk factors and the aneurysm related factors for decision making in management of intracranial aneurysm between endovascular and microsurgical modalities of management. Results: The relevance of age of patient, modifiable and nonmodifiable risk actors, family history, rupture status of aneurysm, aneurysm related factors like morphology of aneurysm and multiplicity are discussed here. Perceived differences in efficacy and safety of the two different treatment approaches are commonly used in an attempt to justify treatment choices. Difficulties with treatment selection and case to case management plan should be considered. Conclusion: Properly designed and randomized controlled trials need to be done to address these issues for choosing best management to the patient and definitive guidelines must be made to solve this confusion. Keywords: Intracranial aneurysm, Endovascular coiling, Neurosurgical clipping, Unruptured intracranial aneurysms, Ruptured intracranial aneurysm, Subarachnoid hemorrhage, ISAT

Summary: CpG islands (CGIs) including those at imprinting control regions (ICRs) are protected from de novo methylation in somatic cells. However, many cancers often exhibit CGI hypermethylation, implying that the machinery is impaired in cancer cells. Here, we conducted a comprehensive analysis of CGI methylation during somatic cell reprogramming. Although most CGIs remain hypomethylated, a small subset of CGIs, particularly at several ICRs, was often de novo methylated in reprogrammed pluripotent stem cells (PSCs). Such de novo ICR methylation was linked with the silencing of reprogramming factors, which occurs at a late stage of reprogramming. The ICR-preferred CGI hypermethylation was similarly observed in human PSCs. Mechanistically, ablation of Dnmt3a prevented PSCs from de novo ICR methylation. Notably, the ICR-preferred CGI hypermethylation was observed in pediatric cancers, while adult cancers exhibit genome-wide CGI hypermethylation. These results may have important implications in the pathogenesis of pediatric cancers and the application of PSCs. : In this article, Yamada, Yamamoto and colleagues show that Dnmt3a-mediated DNA methylation occurs at imprinting loci during reprogramming into naive and primed PSCs. Similar de novo ICR methylation is detected in pediatric cancers, which raises the possibility that reprogramming is involved in development of childhood cancers. Keywords: pluripotent stem cells, naive and primed pluripotency, reprogramming, pediatric cancers, DNA methylation, genomic imprinting, CpG islands, Dnmt3a

To identify prognostic factors, array CGH (aCGH) patterns and mutations in WT1 and 9 other genes were analyzed in 128 unilateral Wilms tumors (WTs). Twenty patients had no aCGH aberrations, and 31 had WT1 alterations [silent and WT1 types: relapse-free survival (RFS), 95% and 83%, respectively]. Seventy-seven patients had aCGH changes without WT1 alterations (nonsilent/non-WT1 type) and were subtyped into those with or without +12, 11q−, 16q−, or HACE1 loss. RFS was better for those with than those without +12 (P = .010) and worse for those with than those without 11q−, 16q−, or HACE1 loss (P = .001, .025, or 1.2E-04, respectively). Silent and WT1 type and 8 subtype tumors were integrated and classified into 3 risk groups: low risk for the silent type and +12 subgroup; high risk for the no +12 plus 11q−, 16q−, or HACE1 loss subgroup; intermediate risk for the WT1 type and no +12 plus no 11q−, 16q−, or HACE1 loss subgroup. Among the 27 WTs examined, the expression of 146 genes on chromosome 12 was stronger in +12 tumors than in no +12 tumors, while that of 10 genes on 16q was weaker in 16q− tumors than in no 16q− tumors. Overexpression in 75 out of 146 upregulated genes and underexpression in 7 out of 10 downregulated genes correlated with better and worse overall survival, respectively, based on the public database. +12 was identified as a potential new marker predicting a favorable outcome, and chromosome abnormalities may be related to altered gene expression associated with these abnormalities.

Summary: Fibrodysplasia ossificans progressiva (FOP) is a rare and intractable disorder characterized by extraskeletal bone formation through endochondral ossification. FOP patients harbor gain-of-function mutations in ACVR1 (FOP-ACVR1), a type I receptor for bone morphogenetic proteins. Despite numerous studies, no drugs have been approved for FOP. Here, we developed a high-throughput screening (HTS) system focused on the constitutive activation of FOP-ACVR1 by utilizing a chondrogenic ATDC5 cell line that stably expresses FOP-ACVR1. After HTS of 5,000 small-molecule compounds, we identified two hit compounds that are effective at suppressing the enhanced chondrogenesis of FOP patient-derived induced pluripotent stem cells (FOP-iPSCs) and suppressed the heterotopic ossification (HO) of multiple model mice, including FOP-ACVR1 transgenic mice and HO model mice utilizing FOP-iPSCs. Furthermore, we revealed that one of the hit compounds is an mTOR signaling modulator that indirectly inhibits mTOR signaling. Our results demonstrate that these hit compounds could contribute to future drug repositioning and the mechanistic analysis of mTOR signaling. : Focusing on the ligand-independent constitutive activation of mutated ACVR1 in fibrodysplasia ossificans progressiva (FOP) patients, Ikeya and colleagues have identified two hit compounds that were effective in multiple FOP model mice. One of the hit compounds, TAK 165, was an mTOR signaling modulator that indirectly regulated enhanced mTOR signaling. These findings shed light on a therapeutic strategy for FOP. Keywords: mammalian target of rapamycin (mTOR), induced pluripotent stem cell (iPSC), fibrodysplasia ossificans progressiva (FOP), endochondral ossification, heterotopic ossification, bone morphogenetic protein (BMP), transforming growth factor β (TGF-β), activin A, high-throughput screening (HTS), ACVR1

It remains unclear what cells are proper for the generation of induced pluripotent stem cells (iPSCs). Leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5) is well known as a tissue stem cell and progenitor marker, both of which are reported to be sensitive to reprogramming. In the present study, we examined the reprogramming behavior of Lgr5-expressing cells (Lgr5+ cells). First, we compared reprogramming behavior using mouse Lgr5+ and Lgr5 negative (Lgr5−) hair follicles (HFs). The number of alkaline phosphatase staining-positive cells was lesser in a well of Lgr5+ HFs than in Lgr5− HFs; however, the ratio of Nanog+ SSEA1+ cells in the cell mixture derived from Lgr5+ HFs was much higher than that from Lgr5− HFs. Lgr5+ cells could be induced from mouse embryonic fibroblasts (MEFs) after transduction with Yamanaka factors. As shown in HFs, the progeny of Lgr5+ cells arising from MEFs highly converted into Nanog+ cells and did not form Nanog− colonies. The progeny represented the status of the late reprogramming phase to a higher degree than the nonprogeny. We also confirmed this using human Lg5+ cells. Our findings suggest that the use of Lgr5+ cells will minimize sorting efforts for obtaining superior iPSCs.

Introduction: Mirror Aneurysms [MA] are a subset of multiple aneurysms which account for nearly 5% of all intracranial aneurysms and approximately 40% of all multiple aneurysms. The purpose of our study was to evaluate the etiopathogenesis, preferential location, clinical characteristics and outcome of mirror aneurysms in comparison with non-mirror multiple aneurysms. Methods: We retrospectively reviewed the clinical and radiological data of 358 patients with intracranial aneurysms who were treated at our institute between January 2014 and June 2018. The patients were further divided into non-mirror multiple and mirror aneurysm groups. There were 13 patients who had MA and 45 patients with non-mirror aneurysms [NMA]. Results: Multiple aneurysms were found in 16.2% of all patients [58 out of 358]. MA were observed in 3.6% [13 out of 358 patients]. There was a slight female predominance in the MA group [84.6% vs 73.3%]. The commonest location of MA in our series was MCA. There was no statistically significant difference in age, smoking, hypertension or postoperative outcome between the two groups. Conclusion: Management of mirror aneurysms should be determined individually based on the location, size, and morphology of the aneurysms, as well as the clinical manifestations of the patient. Therefore, emergent treatment of the ruptured aneurysm and staged management of the contra lateral unruptured twin can be considered as a rational treatment strategy to manage mirror aneurysms. The decision of single or multistage approach/surgical or endovascular coiling should be based on the aneurysm location, morphology, rupture status and available expertise

Background: Whole-gland therapy for prostate cancer, which might cause more harm than no therapy (observation or active surveillance), might be a overtreatment. In order to avoid overtreatment as well as undertreatment of localize prostate cancer, novel strategy of organ-preserving therapies have been developed to achieve both cancer control and functional preservation. For the therapeutic techniques, microwave ablation would be an option for lesion-targeted focal therapy to eradicate biopsy-proven cancer lesion with its safety margin. Following our recent pilot clinical study of lesion-targeted focal cryotherapy, prospective clinical trial was designed to investigate the safety and therapeutic effects of lesion-targeted microwave therapy for localized prostate cancer. Methods: This is a single-center, phase I, clinical study to evaluate primarily the safety of lesion-targeted focal microwave treatment for prostate cancer. Patients with a magnetic resonance imaging (MRI)-visible, MR-ultrasound image-fusion targeted biopsy-proven clinically significant cancer will be enrolled. The target sample size is 5. Transrectal ultrasound-guided focal microwave ablation will be performed under general anesthesia. The primary endpoint is adverse events after microwave focal therapy. Secondary endpoint includes to assess both cancer control and quality of life (functional preservation). Discussion: This single-center, phase I, clinical study aims to evaluate the safety and efficacy of lesion-targeted focal microwave treatment for prostate cancer. The importance of this clinical trial is that it may establish new treatment for prostate cancer. Trial registration: This study was registered with Japan Registry of Clinical Trials (jRCTs052190026). Keywords: Focal therapy, Microwave, Prostate cancer, Index lesion

Introduction: Multiple intracranial aneurysms [MIA] occur in 7% to 34% of patients with intracranial aneurysms. They can be treated with both surgical and endovascular techniques. Here we report 2 cases of multiple intracranial aneurysms with 6 and 7 aneurysms respectively who were treated at our institute by surgery followed by a discussion on incidence, conditions associated with multiple aneurysms, ethnicity and management strategies. Methods: A retrospective analysis of 2 patients with incidentally detected aneurysms with 6 and 7 aneurysms respectively, who were treated with microsurgical clipping was conducted. A systematic search was performed using the PUBMED database and relevant articles were reviewed with particular attention to incidence, associated conditions, risk factors and management strategies. Results: Both the patients were females with incidental detection of the aneurysms. One had 6 and the other had 8 aneurysms respectively. Both patients underwent bilateral pterional craniotomy and clipping of all the aneurysms except for one aneurysm in the cavernous ICA, for which the patient is planned for an endovascular procedure. Both had an uneventful postoperative course with the CT angiogram showing obliteration of all the aneurysms except one. Conclusions: There is a lack of prospective randomized controlled trials to analyse management options, particularly in comparing intervention with conservative management. Most of the available data is retrospective in nature and lacks objective short and long-term outcome analysis. Furthermore, we need randomized trials to directly compare clipping and coiling of multiple unruptured aneurysms to decide the best intervention strategy of this pathology. Keywords: management strategies, multiple intracranial aneurysms, risk factors

Objective: Intracranial aneurysms are considered large if >10 mm and giant if >25 mm. The risk of aneurysmal rupture compounds with increase in size of the aneurysm, thus, warranting appropriate intervention. In this study, we have analyzed the outcome and effectiveness of microsurgical procedures in large and giant aneurysms. Methods: A retrospective analysis of all the patients who underwent microsurgical procedures for large and giant cerebral aneurysms from 2014–2018 in our institute was conducted. There were a total of 52 patients, in which direct clipping was performed in 42 (80.7%) patients, proximal trapping in 3 (5.7%) patients, trapping with bypass in 3 (5.7%) patients, suction decompression in 3 (5.7%) patients, and 1 (1.9%) patient underwent surgical reconstruction. Results: Among the 52 patients, in the postoperative period, 1 (1.9%) patient became comatose, 1 (1.9%) patient developed hemiplegia, 1 (1.9%) patient had a transient hemiparesis, and 1 (1.9%) patient had transient lower cranial nerve palsy. Two (3.8%) patients had chronic subdural hematoma during the 3-month follow-up. There was no mortality in our series. Conclusions: There are several treatment strategies available to manage large and giant cerebral aneurysms. In this study, we had minimal morbidity (3.8%), favorable outcome (96.1%), and no mortality. Therefore, we would like to conclude that appropriate microsurgical procedures, in experienced hands, can be considered as first line in the management for large and giant intracranial aneurysms, especially those with complex anatomy, wide neck, mass effect, partial thrombosis, and the presence of critical perforating vessels from the aneurysm wall. Key words: Bypass, Clipping, DIVA, Giant, Intracranial aneurysm, Outcome, Trapping

Summary: Atypical teratoid/rhabdoid tumor (AT/RT), which harbors SMARCB1 mutation and exhibits a characteristic histology of rhabdoid cells, has a poor prognosis because of the lack of effective treatments. Here, we establish human SMARCB1-deficient pluripotent stem cells (hPSCs). SMARCB1-deficient hPSC-derived neural progenitor-like cells (NPLCs) efficiently give rise to brain tumors when transplanted into the mouse brain. Notably, activation of an embryonic stem cell (ESC)-like signature confers a rhabdoid histology in SMARCB1-deficient NPLC-derived tumors and causes a poor prognosis. Consistently, we find the activation of the ESC-like gene expression signature and an ESC-like DNA methylation landscape in clinical specimens of AT/RT. Finally, we identify candidate genes that maintain the activation of the ESC-like signature and the growth of AT/RT cells. Collectively, SMARCB1-deficient hPSCs offer the human models for AT/RT, which uncover the role of the activated ESC-like signature in the poor prognosis and unique histology of AT/RT. : Terada et al. present SMARCB1-deficient human pluripotent stem cell-derived atypical teratoid/rhabdoid tumor (AT/RT) models and show that ESC-like signature is a critical driver of malignant phenotypes of AT/RT. Genetic ablation targeting the maintenance of pluripotency inhibits AT/RT cell growth, suggesting that the ESC-like signature could be a promising therapeutic target for AT/RT. Keywords: atypical teratoid/rhabdoid tumor, pediatric tumor, embryonic stem cell, induced pluripotent stem cell, ESC-like signature, pluripotency, dedifferentiation, SMARCB1

EWS-FLI1, a multi-functional fusion oncogene, is exclusively detected in Ewing sarcomas. However, previous studies reported that rare varieties of osteosarcomas also harbor EWS-ETS family fusion. Here, using the doxycycline-inducible EWS-FLI1 system, we established an EWS-FLI1-dependent osteosarcoma model from murine bone marrow stromal cells. We revealed that the withdrawal of EWS-FLI1 expression enhances the osteogenic differentiation of sarcoma cells, leading to mature bone formation. Taking advantage of induced pluripotent stem cell (iPSC) technology, we also show that sarcoma-derived iPSCs with cancer-related genetic abnormalities exhibited an impaired differentiation program of osteogenic lineage irrespective of the EWS-FLI1 expression. Finally, we demonstrate that EWS-FLI1 contributed to secondary sarcoma development from the sarcoma iPSCs after osteogenic differentiation. These findings demonstrate that modulating cellular differentiation is a fundamental principle of EWS-FLI1-induced osteosarcoma development. This in vitro cancer model using sarcoma iPSCs should provide a unique platform for dissecting relationships between the cancer genome and cellular differentiation.

As the quintessential reprogramming model, OCT3/4, SOX2, KLF4, and c-MYC re-wire somatic cells to achieve induced pluripotency. Yet, subtle differences in methodology confound comparative studies of reprogramming mechanisms. Employing transposons, we systematically assessed cellular and molecular hallmarks of mouse somatic cell reprogramming by various polycistronic cassettes. Reprogramming responses varied in the extent of initiation and stabilization of transgene-independent pluripotency. Notably, the cassettes employed one of two KLF4 variants, differing only by nine N-terminal amino acids, which generated dissimilar protein stoichiometry. Extending the shorter variant by nine N-terminal amino acids or augmenting stoichiometry by KLF4 supplementation rescued both protein levels and phenotypic disparities, implicating a threshold in determining reprogramming outcomes. Strikingly, global gene expression patterns elicited by published polycistronic cassettes diverged according to each KLF4 variant. Our data expose a Klf4 reference cDNA variation that alters polycistronic factor stoichiometry, predicts reprogramming hallmarks, and guides comparison of compatible public data sets.

Objective: Surgical treatment of vertebral artery (VA) and VA-proximal posterior inferior cerebellar artery (PICA) aneurysms poses a special challenge to the operating surgeon because of the complex anatomy of the neck and the location of the aneurysm. We report our surgical results of unruptured VA and VA-PICA aneurysms operated on through the transcondylar fossa approach., Methods: We retrospectively analyzed the data of 20 patients with unruptured VA and VA-PICA aneurysms who were treated by the transcondylar fossa approach in a single institution from November 2014 to March 2018. Data including clinical profile, radiology, complications, and outcome were analyzed., Results: Five patients had VA aneurysms and 15 had VA-PICA aneurysms. All were unruptured aneurysms, and 4 patients were symptomatic. All underwent surgical treatment through the transcondylar fossa approach. Proximal VA occlusion alone for 4 patients along with revascularization for 3 patients was performed. Twelve patients underwent clipping and 1 underwent wrapping of the aneurysm. The transcondylar fossa approach was adequate to expose the aneurysms successfully. There were no intraoperative complications encountered. Only 3 patients had transient postoperative complications. Follow-up imaging showed complete occlusion of all clipped aneurysms and complete thrombosis of the sac in all patients with proximal VA occlusion with or without revascularization., Conclusions: Although the incidence of rupture of asymptomatic unruptured VA and VA-PICA aneurysms is low, they should be considered for surgical treatment because they carry higher early mortality and morbidity after rupture. The transcondylar fossa approach provides adequate exposure of the aneurysm without permanent lower cranial nerve morbidity., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Glossopharyngeal neuralgia (GPN) is a rare condition, commonly misdiagnosed as trigeminal neuralgia. Microvascular decompression (MVD) is considered the first line of treatment in medically refractive idiopathic GPN, and the recurrence rate is reported to be 7.1%. We present our first case report on the surgical management of a patient with recurrent GPN and analyze the possible causes for recurrence after MVD., Case Description: A 73-year-old gentleman was referred to us with a diagnosis of recurrent left GPN. He was diagnosed 6 years ago with left mandibular branch trigeminal neuralgia for the complaint of left-side tongue pain. He received left mandibular nerve block twice earlier and Gamma Knife radiotherapy 2 years ago without relief. A year ago he was diagnosed with GPN by a neurosurgeon, and MVD was performed. The posterior inferior cerebellar artery and vertebral artery were the offending vessels and were interposed with Teflon. After a temporary pain relief, the patient had a recurrence. Redo-MVD with transposition of the vertebral artery and further interposition of posterior inferior cerebellar artery did not help. After referral to us, we operated on the patient again and found 2 small arteries at the root entry zone (REZ). Interposition with Teflon and splitting of the rootlets relieved the pain., Conclusions: MVD is considered the first line of treatment in drug-resistant idiopathic GPN. Thorough exploration of REZ for small arteries and veins is mandatory to prevent recurrence. Vascular compression can occur at the cisternal portion or at the REZ. In recurrent cases, splitting of the glossopharyngeal nerve rootlets adds to the good outcome., (Copyright © 2018 Elsevier Inc. All rights reserved.)