Search

A mucoepidermoid carcinoma (MEC) is the most common malignant tumor of the salivary gland. It frequently occurs in the parotid and minor salivary glands, but rarely originates from the sublingual gland. We report a case of a low-grade MEC arising from the sublingual gland with a MAML2 gene split on fluorescence in situ hybridization (FISH). In May 2017, a 57-year-old woman visited our hospital with left-sided tongue numbness and swelling of the floor of the mouth. We performed a biopsy, but the lesion was indistinguishable from malignant tumors such as MEC, or atypical epithelium associated with inflammation. Subsequently, an MEC was suspected based on computed tomography findings of invasion into the bone marrow and destruction of the outer margin of the mandibular cortex. In July 2017, tracheostomy, bilateral supraomohyoid neck dissection, combined resection of the floor of the mouth and reconstruction of the free peroneal composite flap with a vascular handle were performed under general anesthesia. Although perineural and mandibular invasion was observed, the tumor was considered a low-grade malignancy based on histopathological findings. Furthermore, a split signal in the MAML2 gene was detected on detailed molecular analysis using FISH. No recurrence was observed more than three years after definitive surgery. The presence of the MAML2 fusion gene is useful for the accurate diagnosis of an MEC. Overall, we report a rare case of an MEC in the sublingual gland with mandibular invasion where MAML2 fusion was confirmed.

COVID-19 is pandemic since 2020 and further information is necessary on the risk factors associated with the infection of SARS-CoV-2. As an entry mechanism, SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) as receptor and transmembrane serine protease 2 (TMPRSS2) to activate fusion with host plasma membrane. Because dysgeusia is an early symptom of COVID-19, we here studied the expression of ACE2 and TMPRSS2 in the tongue and the associated tissues of mice and humans with immunohistochemistry and immunoblot analysis. ACE2 expression was low in the human tongue but was observed in the squamous epithelium, perineurium, arterial wall, salivary glands as well as taste buds. In contrast, mice showed high expression. In sharp contrast, TMPRSS2 expression was high in all the cells mentioned above in humans but relatively low in mice except for salivary glands. We then performed semi-quantitation of immunohistochemistry data of human ACE2 and TMPRSS2 and analyzed for age, sex, alcohol intake, and smoking habit with logistic regression analysis. We found that alcohol intake and female gender were the significant risk factors for increasing TMPRSS2 expression. In conclusion, TMPRSS2 is an important factor to be considered regarding SARS-CoV-2 entry and amplification in the oral cavity, which is promoted through drinking habit.

Lingual artery (LA) aneurysms are particularly rare, and pseudoaneurysms are associated with trauma, infection, and surgical intervention. LA aneurysms can be fatal if not recognised or treated; however, only a few cases of idiopathic LA aneurysms have been reported in the literature, all of which have been described as pseudoaneurysms. To address this knowledge gap in reporting a true LA aneurysm, here, we describe a 55-year-old woman with an idiopathic aneurysm of the lingual artery. The lesion was detected by another department on a computed tomographic angiography of the neck, which was performed as a post-aneurysmectomy evaluation of the right internal carotid artery. The embolisation failed twice, after which we performed an aneurysmectomy of the left atrium. A histopathological examination of the excised aneurysms revealed fibromuscular dysplasia (FMD). Thus, we believe that FMD may be a cause of external LA aneurysms. Our findings will be relevant for oral surgeons and physicians who may consider FMD as a differential diagnosis when treating multiple LA aneurysms.

Ossifying fibroma is a fibro-osseous lesion of the jaw and usually occurs as a single lesion. Little is known about ossifying fibromas, which occur as a manifestation of hyperparathyroidism-jaw tumor syndrome (HPT-JT), an autosomal dominant disorder. We experienced a patient with HPT-JT who had ossifying fibromas on both sides of the mandible. A 32-year-old female was referred to our department because of swelling on the right side of the mandible. She had a history of parathyroid adenomas and endometrial hyperplasia; however, there was no family history of parathyroid, mandibular, or renal lesions. She was diagnosed with recurrent parathyroid adenoma close to the time of her visit to our department. A biopsy revealed that the jaw lesion was an ossifying fibroma, and genetic testing revealed HPT-JT. She underwent surgery for the parathyroid and mandibular lesions and is currently undergoing follow-up. Accurate diagnosis of HPT-JT is important because it is an inherited condition and is associated with a high incidence of parathyroid carcinoma. This case indicates that cooperation among multiple medical care departments is essential for proper diagnosis and treatment of HPT-JT.

Objective Owing to variations in the exterior appearances of noncancerous diseases in the oral cavity, clinicians may have difficulty diagnosing oral squamous cell carcinoma (OSCC). Tissue biopsy is confirmatory, but invasive. Therefore, reliable tumor markers for OSCC are required. Here, exosomal Alix (exoAlix) levels were measured in serum/salivary samples from patients with OSCC and healthy controls (HCs). Methods Fifty-seven patients admitted to Nagoya University Hospital from 2017 through 2019 were enrolled, and serum samples (OSCC, n = 29; HC, n = 21) and/or saliva samples (OSCC, n = 23; HC, n = 20) were collected. Exosomal fractions were isolated using ultracentrifugation. ExoAlix levels were measured using enzyme-linked immunosorbent assay. Results Serum/salivary exoAlix levels were significantly higher in patients with OSCC than in HCs. Receiver operating characteristic analyses revealed that sensitivity, specificity, positive predictive value, and area under the curve were 0.345, 1.000, 1.000, and 0.685, respectively, for serum exoAlix and 0.348, 1.000, 1.000, and 0.712, respectively, for salivary exoAlix at optimal cut-off values (serum, 0.205; saliva, 0.193). All tested OSCC tissue sections (n = 21) were immuno-reactive for Alix. Conclusion Serum and salivary exoAlix were identified as potential diagnostic OSCC biomarkers. Serum exoAlix was suitable for prediction of therapeutic responses.

Post-transplant lymphoproliferative disorders (PTLDs) are lesions that proliferate lymphocytes or plasma cells and are caused by immunosuppression after organ transplantation or hepatopoietic stem cell transplantation. According to the 2016 WHO classification, PTLDs are classified into four types: early lesions, polymorphic PTLDs, monomorphic PTLDs, and classical Hodgkin lymphoma-type PTLDs. We report a case of PTLD that first occurred in the oral and maxillofacial area more than ten years after living renal transplantation. A sixty-one-year-old man visited our department in the middle of August 2013 because of right parotid gland swelling. We consulted with an otorhinolaryngologist and prescribed antibiotics to determine whether the swelling was parotitis or a tumor; however, the swelling did not improve. At the end of September 2013, a tumor was found in the right palatine tonsil; consequently, a biopsy was performed. After the biopsy, the lesion was diagnosed as monomorphic PTLD (diffuse large B-cell lymphoma), and the patient was admitted to the hematology and oncology ward. Immunosuppressants were interrupted or reduced. However, the tumor continued to swell, and R-CHOP treatment was started. The therapeutic value was PR, and the patient’s general condition was good; therefore, in mid-February, he discharged. However, at the end of April 2014, the patient experienced septic shock due to pneumonia and passed away the next day. As this case shows, it is important for oral and maxillofacial surgeons to consider the possibility of PTLD in the oral and maxillofacial area.

Previous studies have shown that dissolved substances in some natural hot springs have analgesic/anti-nociceptive and anti-inflammatory actions. However, the mechanisms underlying how such dissolved substances exert these actions are not fully understood. In the present study on mice, we examined the analgesic/anti-nociceptive and anti-inflammatory properties of a mineral cream containing natural hot spring ingredients. The anti-nociceptive effects of the mineral cream were assessed by using the von Frey test. Application of the mineral cream to the hind paw of mice produced a significant anti-nociceptive effect compared to control. The anti-nociceptive effects of the mineral cream were also assessed following the injection of complete Freund's adjuvant (CFA) into the hind paws of mice after pre-treatment for one or four weeks with the mineral cream. Histological experiments with light microscopy showed that the mineral cream did not reduce inflammation caused by the CFA treatment. In addition, the mineral cream did not inhibit oxidative stress as evidenced by increased levels of oxidative metabolites (d-ROMs) and biological anti-oxidant potential (BAP). These results suggest that the mineral cream does not exert a protective effect against inflammation, and that the constituents of the mineral cream may produce their anti-nociceptive effects transdermally via different mechanisms including the nervous system.

The 5-HT5A receptor is arguably the least understood 5-HT receptor. Despite widespread expression in human and rodent brains it lacks specific ligands. Our previous results suggest that 5-HT5A receptor antagonists may be effective against cognitive impairment in schizophrenia. In this study, using behavioral, immunohistochemical, electrophysiological and microdialysis techniques, we examined the mechanism by which ASP5736, a novel and selective 5-HT5A receptor antagonist, exerts a positive effect in animal models of cognitive impairment. We first confirmed the effect of ASP5736 on cognitive deficits in rats treated subchronically with phencyclidine hydrochloride (PCP) using an attentional set shifting task. Subsequently, we identified 5-HT5A receptors in dopaminergic (DAergic) neurons and parvalbumin (PV)-positive interneurons in the ventral tegmental area (VTA) and in PV-positive interneurons in the medial prefrontal cortex (mPFC). Burst firing of the DAergic cells in the parabrachial pigmental nucleus (PBP) in the VTA, which predominantly project to the mPFC, was significantly enhanced by treatment with ASP5736. In contrast, ASP5736 exerted no significant effect on either the firing rate or burst firing in the DA cells in the paranigral nucleus (PN), that project to the nucleus accumbens (N. Acc.). ASP5736 increased the release of DA and gamma-aminobutyric acid (GABA) in the mPFC of subchronically PCP-treated rats. These results support our hypothesis that ASP5736 might block the inhibitory 5-HT5A receptors on DAergic neurons in the VTA that project to the mPFC, and interneurons in the mPFC, and thereby improve cognitive impairment by preferentially enhancing DAergic and GABAergic neurons in the mPFC.

Maffucci syndrome, first described in 1881, is a rare, non-hereditary skeletal disorder characterized by multiple enchondromas in combination with soft tissue hemangiomas. Recent studies have implicated somatic mutations in IDH1/2 contributing to the pathogenesis of Maffucci syndrome. This study describes the first case of Maffucci syndrome harboring a mutation in IDH1, which was associated with a hemangioma in the oral mucosa. A 32-year-old man, who was diagnosed with Maffucci syndrome during childhood, was referred to our department in April 2020 due to a mass in the left buccal mucosa. The mass was soft, dome-shaped, had dark red protrusions and well-defined borders, and the dimensions were approximately 15 × 10 mm. Magnetic resonance imaging revealed a mass with a dimension of 13 × 10 mm, which appeared hyperintense on T2-weighted images. The vascular lesion was surgically resected under local anesthesia owing to hemangioma diagnosis. We then analyzed the IDH1/2 sequences using DNA extracted from the excised tumor tissue and peripheral blood. The analysis revealed the presence of a heterozygous mutation in IDH1 in the tumor tissue, corresponding to an R132C substitution. The mutation was not present in peripheral blood DNA. After over one year of resection, the patient is presently free from tumor recurrence and is under follow-up for the early detection of recurrent hemangioma.

Objective Members of the Notch family are frequently dysregulated in various types of cancers, and these alterations can lead to oncogenesis or tumor suppression depending on the context. The aim of this study was to elucidate the relationship between members of the Notch family and oral squamous cell carcinoma (OSCC) tumorigenesis, with a focus on epigenetic alteration, especially DNA methylation. Material and methods We analyzed the expression and DNA methylation of members of the Notch family in six OSCC cell lines. Additionally, we evaluated the DNA methylation level and the frequency of Notch3 methylation in clinical samples and compared the results between tumor and normal tissues using The Cancer Genome Atlas (TCGA) dataset. Further, we comprehensively evaluated DNA methylation and gene mutation of Notch3 in tumor tissues. Results Notch1, Notch2, and Notch4 were substantially expressed in all the OSCC cells, whereas Notch3 expression was not detected; moreover, Notch3 was highly methylated at the promoter region in one of the six cell lines. In the OSCC clinical samples, Notch3 methylation was significantly higher in tumor than in normal tissues (P = 0.04). Intriguingly, DNA methylation and loss of function mutation of Notch3 tended to be mutually exclusive. Conclusion Our data indicate that Notch3 is downregulated by multiple mechanisms during OSCC tumorigenesis, mainly due to DNA methylation.

Introduction: Direct oral anticoagulants are widely used in patients with nonvalvular atrial fibrillation (AF) to reduce the risk of stroke and systemic embolism, however, there is not enough real-world data of their effectiveness and safety in patients with worsening renal function (WRF). Xarelto post-authorization safety and effectiveness study in Japanese patients with atrial fibrillation (XAPASS) is a prospective observational post-marketing surveillance study mandated by the Japanese authority. It aims to examine safety and effectiveness of rivaroxaban in everyday clinical practice. This analysis investigated one year outcomes among patients with WRF and stable renal function (SRF) in XAPASS. Methods: One year follow-up data of 9578 patients enrolled in XAPASS were analyzed to evaluate baseline characteristics and safety/effectiveness profile among patients with WRF and SRF. WRF was defined as a decrease of more than 20% from enrollment creatinine clearance measurement at any time point during the study. SRF was defined as the absence of WRF at any time. Results: We identified 1229 patients (12.8%) with WRF and 6280 patients (65.6%) with SRF among 9578 patients. WRF patients were significantly older, and had significantly higher mean CHA 2 DS 2 -VASc score and modified HAS-BLED score compared to SRF patients. Prevalence of hypertension, congestive heart failure, ischemic stroke/transient ischemic attack, and myocardial infarction was higher in WRF patients. There was no difference in rates of major bleeding (hazard ratio (HR) 1.20; 95% confidence interval (CI) 0.75-1.90; p=0.45) or the composite endpoint of stroke, systemic embolism or myocardial infarction (HR 1.06; 95% CI 0.65-1.71; p=0.82) between patients with WRF and SRF. WRF patients experienced a higher incidence of transfusion of 2 units or more (0.46 versus 0.14 events per 100 patient-years; HR 3.19; 95% CI 1.04-9.74; p=0.03) versus SRF patients. Rates of other major bleeding subgroups defined according to ISTH criteria were similar between patients with WRF and SRF. Conclusions: WRF during rivaroxaban treatment did not significantly increase the rates of major bleeding or thromboembolic events, although it was associated with a higher incidence of transfusion of 2 units or more.

Exosomes are 50-100-nm-diameter membrane vesicles released from various types of cells. Exosomes retain proteins, mRNAs and miRNAs, which can be transported to surrounding cells. CD109 is a glycosylphosphatidylinositol-anchored glycoprotein, and is released from the cell surface to the culture medium in vitro. Recently, it was reported that secreted CD109 from the cell surface downregulates transforming growth factor-β signaling in human keratinocytes. In this study, we revealed that CD109 is a component of the exosome in conditioned medium. FLAG-tagged human CD109 (FLAG-CD109) in conditioned medium secreted from HEK293 cells expressing FLAG-CD109 (293/FLAG-CD109) was immunoprecipitated with anti-FLAG affinity gel, and the co-precipitated proteins were analyzed by mass spectrometry and western blotting. Exosomal proteins were associated with CD109. We revealed the presence of CD109 in exosome fractions from conditioned medium of 293/FLAG-CD109. Moreover, the localization of CD109 in the exosome was demonstrated using immuno-electron microscopy. When we used HEK293 cells expressing FLAG-tagged truncated CD109, which does not contain the C-terminal region, the association of truncated CD109 with exosomes was not detected in conditioned medium. These findings indicate that CD109 is an exosomal protein and that the C-terminal region of CD109 is required for its presence in the exosome.

Metal dental restoration materials cause dose enhancement upstream and dose disturbance downstream of the high‐density inhomogeneous regions in which these materials are used. In this study, we evaluated the impact of a dental metallic crown (DMC) on intensity‐modulated radiotherapy (IMRT) and volumetric‐modulated arc therapy (VMAT) for head and neck cancer. Additionally, the possibility of sparing the oral mucosa from dose enhancement using an individual intraoral mouthpiece was evaluated. An experimental oral phantom was designed to verify the dosimetric impact of a DMC. We evaluated the effect on single beam, parallel opposing beam, arc beam, IMRT, and VMAT treatment plans. To evaluate the utility of a 3‐mm‐thick intraoral mouthpiece, the doses across the mouthpiece were measured. For single beam irradiation, the measured doses at the entrance and exit planes of the DMC were 51% higher and 21% lower than the calculated dose by the treatment planning system, respectively. The maximum dose enhancements were 22% and 46% for parallel opposing beams and the 90° arc rotation beam, respectively. For IMRT and VMAT, the measured doses adjacent to the DMC were 12.2%±6.3% (mean±1.96 SD) and 12.7%±2.5% higher than the calculated doses, respectively. With regard to the performance of the intraoral mouthpiece for the IMRT and VMAT cases, the disagreement between measured and calculated doses at the outermost surface of the mouthpieces were −2.0%, and 2.0%, respectively. Dose enhancements caused by DMC‐mediated radiation scattering occurred during IMRT and VMAT. Because it is difficult to accurately estimate the dose perturbations, careful consideration is necessary when planning head and neck cancer treatments in patients with DMCs. To spare the oral mucosa from dose enhancement, the use of an individual intraoral mouthpiece should be considered. PACS numbers: 87.55.km, 87.55.N‐, 87.55.Qr

Previous studies have shown that dissolved substances in some natural hot springs have analgesic/anti-nociceptive and anti-inflammatory actions. However, the mechanisms underlying how such dissolved substances exert these actions are not fully understood. In the present study on mice, we examined the analgesic/anti-nociceptive and anti-inflammatory properties of a mineral cream containing natural hot spring ingredients. The anti-nociceptive effects of the mineral cream were assessed by using the von Frey test. Application of the mineral cream to the hind paw of mice produced a significant anti-nociceptive effect compared to control. The anti-nociceptive effects of the mineral cream were also assessed following the injection of complete Freund's adjuvant (CFA) into the hind paws of mice after pre-treatment for one or four weeks with the mineral cream. Histological experiments with light microscopy showed that the mineral cream did not reduce inflammation caused by the CFA treatment. In addition, the mineral cream did not inhibit oxidative stress as evidenced by increased levels of oxidative metabolites (d-ROMs) and biological anti-oxidant potential (BAP). These results suggest that the mineral cream does not exert a protective effect against inflammation, and that the constituents of the mineral cream may produce their anti-nociceptive effects transdermally via different mechanisms including the nervous system.

The 5-HT

Stem cells from human exfoliated deciduous teeth (SHEDs) can regenerate various tissues. We investigated the impact of SHED-conditioned medium (SHED-CM) on myocardial injury in a mouse model of ischemia-reperfusion (I/R). Wild-type (WT) mice were subjected to myocardial ischemia followed by reperfusion. SHED-CM was intravenously injected at 5 min after reperfusion. Administration of SHED-CM reduced myocardial infarct size as well as decreased apoptosis and inflammatory cytokine levels, such as TNF-α, IL-6 and IL-β, in the myocardium following I/R. In cultured cardiac myocytes, SHED-CM significantly suppressed apoptosis under hypoxia/serum-deprivation and reduced LPS-induced expression of pro-inflammatory genes. Furthermore, anti-apoptotic action of SHED-CM was stronger than bone marrow-derived stem cell (BMSC)-CM or adipose-derived stem cell (ADSC)-CM in cardiac myocytes. SHED-CM contains a higher concentration of hepatocyte growth factor (HGF) than BMSC-CM and ADSC-CM and neutralization of HGF attenuated the inhibitory actions of SHED-CM on apoptosis in cardiac myocytes. Finally, WT mice were intravenously treated with an HGF-depleted SHED-CM, followed by myocardial I/R. HGF depletion significantly attenuated the inhibitory actions of SHED-CM on myocardial infarct size and apoptosis after I/R. SHED-CM protects the heart from acute ischemic injury because it suppresses inflammation and apoptosis. SHED-CM could be a useful treatment option for acute myocardial infarction.

The objective of this study is to examine the effect of acarbose, an alpha-glucosidase inhibitor, on body weight in a real-life setting by pooling data from post-marketing surveillance.Data from 10 studies were pooled (n=67,682) and the effect of acarbose on body weight was analysed taking into account baseline body weight, glycemic parameters and other baseline characteristics.The mean relative reduction in body weight was 1.45 ± 3.24% at the 3-month visit (n=43,510; mean baseline 73.4 kg) and 1.40 ± 3.28% at the last visit (n=54,760; mean baseline 73.6 kg) (both p0.0001). These reductions were dependent on baseline body weight (overweight: -1.33 ± 2.98% [n=13,498; mean baseline 71.6 kg]; obese: -1.98 ± 3.40% [n=20,216; mean baseline 81.3 kg]). When analysed by baseline glycemic parameter quartiles, the reduction was independent of fasting plasma glucose (FPG), postprandial plasma glucose (PPG), glycated hemoglobin (HbA1c) and postprandial glucose excursion (PPGE). A bivariate analysis of covariance identified female sex, South East Asian and East Asian ethnicity, younger age, higher body mass index, short duration of diabetes, and no previous treatment as factors likely to impact positively on body weight reduction with acarbose.This post-hoc analysis showed that acarbose treatment reduces body weight independent of glycemic control status but dependent on baseline body weight.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial hyperplasia and chronic inflammation, which lead to the progressive destruction of cartilage and bone in the joints. Numerous studies have reported that administrations of various types of MSCs improve arthritis symptoms in animal models, by paracrine mechanisms. However, the therapeutic effects of the secreted factors alone, without the cell graft, have been uncertain. Here, we show that a single intravenous administration of serum-free conditioned medium (CM) from human deciduous dental pulp stem cells (SHED-CM) into anti-collagen type II antibody-induced arthritis (CAIA), a mouse model of rheumatoid arthritis (RA), markedly improved the arthritis symptoms and joint destruction. The therapeutic efficacy of SHED-CM was associated with an induction of anti-inflammatory M2 macrophages in the CAIA joints and the abrogation of RANKL expression. SHED-CM specifically depleted of an M2 macrophage inducer, the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (ED-Siglec-9), exhibited a reduced ability to induce M2-related gene expression and attenuate CAIA. SHED-CM also inhibited the RANKL-induced osteoclastogenesis in vitro. Collectively, our findings suggest that SHED-CM provides multifaceted therapeutic effects for treating CAIA, including the ED-Siglec-9-dependent induction of M2 macrophage polarization and inhibition of osteoclastogenesis. Thus, SHED-CM may represent a novel anti-inflammatory and reparative therapy for RA.

Oxidative stress and the ubiquitin-proteasome system play a key role in the pathogenesis of Parkinson disease. Although the herbicide paraquat is an environmental factor that is involved in the etiology of Parkinson disease, the role of 26S proteasome in paraquat toxicity remains to be determined. Using PC12 cells overexpressing a fluorescent protein fused to the proteasome degradation signal, we report here that paraquat yielded an inhibitory effect on 26S proteasome activity without an obvious decline in 20S proteasome activity. Relative low concentrations of proteasome inhibitors caused the accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2), which is targeted to the ubiquitin-proteasome system, and activated the antioxidant response element (ARE)-dependent transcription. Paraquat also upregulated the protein level of Nrf2 without increased expression of Nrf2 mRNA, and activated the Nrf2-ARE pathway. Consequently, paraquat induced expression of Nrf2-dependent ARE-driven genes, such as γ-glutamylcysteine synthetase, catalase, and hemeoxygenase-1. Knockdown of Nrf2 or inhibition of γ-glutamylcysteine synthetase and catalase exacerbated paraquat-induced toxicity, whereas suppression of hemeoxygenase-1 did not. These data indicate that the compensatory activation of the Nrf2-ARE pathway via inhibition of 26S proteasome serves as part of a cellular defense mechanism to protect against paraquat toxicity.

Background aims Acute respiratory distress syndrome (ARDS) is a severe inflammatory disorder characterized by acute respiratory failure, resulting from severe, destructive lung inflammation and irreversible lung fibrosis. We evaluated the use of stem cells derived from human exfoliated deciduous teeth (SHEDs) or SHED-derived serum-free conditioned medium (SHED-CM) as treatments for bleomycin (BLM)-induced mice acute lung injury (ALI), exhibiting several pathogenic features associated with the human disease ARDS. Methods Mice with BLM-induced ALI with or without SHED or SHED-CM treatment were examined for weight loss and survival. The lung tissue was characterized by histological and real-time quantitative polymerase chain reaction analysis. The effects of SHED-CM on macrophage differentiation in vitro were also assessed. Results A single intravenous administration of either SHEDs or SHED-CM attenuated the lung injury and weight loss in BLM-treated mice and improved their survival rate. Similar recovery levels were seen in the SHEDs and SHED-CM treatment groups, suggesting that SHED improves ALI by paracrine mechanisms. SHED-CM contained multiple therapeutic factors involved in lung-regenerative mechanisms. Importantly, SHED-CM attenuated the BLM-induced pro-inflammatory response and generated an anti-inflammatory/tissue-regenerating environment, accompanied by the induction of anti-inflammatory M2-like lung macrophages. Furthermore, SHED-CM promoted the in vitro differentiation of bone marrow–derived macrophages into M2-like cells, which expressed high levels of Arginase1 , CD206 and Ym-1 . Discussion Our results suggest that SHED-secreted factors provide multifaceted therapeutic effects, including a strong M2-inducing activity, for treating BLM-induced ALI. This work may open new avenues for research on stem cell–based ARDS therapies.

BACKGROUND: Recently, several studies have demonstrated that absolute lymphocyte counts (ALC) after induction therapy predicted treatment outcome. To address this issue, we here assessed the impact of the ALC at the end of induction therapy on outcomes in childhood ALL. METHODS: We reviewed 141 cases of pediatric ALL with 1-21 years of age treated on the Japan Association Childhood Leukemia Study group ALL-02 series of treatment trials between 2002 and 2013. Patients with Philadelphia chromosome-positive ALL were excluded. Variables retrospectively analyzed included ALC at several time points during remission induction, age at diagnosis, gender, initial white blood cell count (WBC), cytogenetics, immunological phenotype, stratified risk, treatment response for bone marrow (the percentage of blasts at day 15), and outcome. Events in the analysis of event-free survival (EFS) included induction failure, death, relapse and secondary malignant neoplasm. The comparison of categorical variables between groups was performed by chi-square test. The probability of EFS and overall survival (OS) were analyzed with the use of the Kaplan–Meier method and a stratified log-rank test. A multivariate analysis of survival was performed with the use of a Cox proportional-hazard model to evaluate the treatment effect with adjustment for stratification factors. RESULTS: The subjects included 121 of B-precursor ALL, 10 of T cell ALL, and 4 of acute mixed lineage leukemia/ acute unclassified leukemia. We found high WBC count at diagnosis (>100K/microL) and slow early responder for bone marrow at day 15 to be an unfavorable prognostic indicator, and also the ALC at the end of induction (day29) to be a statistically significant predictor of improved OS and EFS in our cohort. Patients with ALC ≥ 800/microL had a superior 5-year overall survival (100 ± 1.7% vs 88.1 ± 4.3 %, p=0.0001) and EFS (98.3 ± 1.7% vs 81.8 ± 5.0 %, p=0.0001). Multivariate analysis demonstrated that ALC at day29 was an independent, clinically significant predictor of improved EFS and OS after controlling WBC at diagnosis, gender, age at diagnosis, and cytogenetics. Multiple regression analysis adjusting for initial WBC count, peripheral blast counts at day8, and cytogenetics, also revealed an independent relationship (p=0.005) between treatment response (the percentage of blasts at day 15) and ALC at day29. CONCLUSIONS: ALC is a simple, statistically significant prognostic factor in childhood ALL that may refine current risk stratification algorithms. Disclosures No relevant conflicts of interest to declare.