Targeting IGF2-IGF1R Signaling to Reprogram the Tumor Microenvironment for Enhanced Viro-Immunotherapy.

BACKGROUND: The FDA approval of oncolytic herpes simplex-1 virus (oHSV) therapy underscores its therapeutic promise and safety as a cancer immunotherapy. Despite this promise, the current efficacy of oHSV is significantly limited to a small subset of patients largely due to the resistance in tumor and tumor microenvironment (TME). METHODS: RNA sequencing (RNA-Seq) was used to identify molecular targets of oHSV resistance. Intracranial human and murine glioma or breast cancer brain metastasis (BCBM) tumor-bearing mouse models were employed to elucidate the mechanism underlying oHSV therapy-induced resistance. RESULTS: Transcriptome analysis identified IGF2 as one of the top secreted proteins following oHSV treatment. Moreover, IGF2 expression was significantly upregulated in 10 out of 14 recurrent GBM patients after treatment with oHSV, rQNestin34.5v.2 (71.4%) (p=0.0020) (ClinicalTrials.gov, NCT03152318). Depletion of IGF2 substantially enhanced oHSV-mediated tumor cell killing in vitro and improved survival of mice bearing BCBM tumors in vivo. To mitigate the oHSV-induced IGF2 in the TME, we constructed a novel oHSV, oHSV-D11mt, secreting a modified IGF2R domain 11 (IGF2RD11mt) that acts as IGF2 decoy receptor. Selective blocking of IGF2 by IGF2RD11mt significantly increased cytotoxicity, reduced oHSV-induced neutrophils/PMN-MDSCs infiltration, and reduced secretion of immune suppressive/proangiogenic cytokines, while increased CD8+cytotoxic T lymphocytes (CTLs) infiltration, leading to enhanced survival in GBM or BCBM tumor-bearing mice. CONCLUSION: This is the first study reporting that oHSV-induced secreted IGF2 exerts a critical role in resistance to oHSV therapy, which can be overcome by oHSV-D11mt as a promising therapeutic advance for enhanced viro-immunotherapy.

Determining the Optimal Dosage of Dexmedetomidine for Smooth Emergence in Older Patients Undergoing Spinal Surgery: A Study of 44 Cases.

BACKGROUND Emergence agitation, or delirium, occurs during early recovery from general anesthesia and involves disorientation, excitation, and uncontrolled physical movements. Dexmedetomidine is an alpha agonist that has sedative, anxiolytic, analgesic, and sympatholytic activities and is used as a continuous infusion to prevent emergence agitation. This study aimed to evaluate patients aged 65 years and older undergoing general anesthesia to determine the 90% effective dose (ED90) of dexmedetomidine continuous intraoperative infusion to prevent emergence agitation. MATERIAL AND METHODS We enrolled 44 patients aged 65 years and older undergoing spinal surgery under general anesthesia. Dexmedetomidine administration commenced 30 minutes before surgery completion, with a predetermined infusion dose (µg/kg/h), without a loading dose. The initial dose was 0.2 µg/kg/h, and subsequent step size was ±0.05 µg/kg/h. We tried to find ED90 of dexmedetomidine using the biased-coin design. Vital signs, extubation quality scores, extubation-related complications, and postoperative outcomes were monitored. RESULTS Dexmedetomidine ED90 for smooth emergence in older patients was 0.34 µg/kg/h. Peri-extubation vital signs remained within 20% of baseline values, without requiring pharmacological intervention. No hypoxia, hypoventilation, or post-extubation agitation occurred. In the recovery room, 1 patient briefly exhibited excitement but quickly calmed. Nine patients initially unresponsive in the recovery room fully awoke and were promptly discharged. CONCLUSIONS For older patients who are vulnerable to adverse effects of anesthetics and opioids, dexmedetomidine enables gentle awakening without adverse vital sign changes, respiratory depression, excessive sedation, or emergence agitation (ED90=0.34 µg/kg/h). Further studies should involve a larger patient cohort, considering diverse medical conditions in older individuals.

The effect of ulinastatin on acute kidney injury in patients undergoing off-pump cardiac bypass surgery.

BACKGROUND: Ulinastatin, an anti-inflammatory and antioxidant trypsin inhibitor, has shown potential in mitigating acute kidney injury (AKI) and reducing serum creatinine levels after various surgeries. This retrospective study aimed to evaluate the effects of ulinastatin on AKI in patients undergoing off-pump coronary artery bypass (OPCAB) surgery. METHODS: We hypothesized that the administration of ulinastatin could prevent AKI in OPCAB. Electrical medical records were reviewed to identify OPCAB patients between January 2015 and June 2020. The utilization of ulinastatin was randomly determined and applied during this period. Acute kidney injury was defined according to the KDIGO guideline, and its incidence was compared between the ulinastatin administration group and the control group. To investigate the effect of ulinastatin on renal function, multivariate logistic regression analysis was used to calculate propensity scores for each group. RESULTS: A total 454 OPCAB were performed, and after following inclusion and exclusion process, 100 patients were identified in the ulinastatin group and 303 patients in the control group. Using 1:2 propensity score matching, we analyzed 100 and 200 patients in the ulinastatin and control groups. The incidence of AKI was similar between the groups (2.5% for the control group, 2.0% for the ulinastatin group, p > 0.999). However, the serum creatinine value on the first post-operative day were significantly lower in the ulinastatin group compared to the control group (0.774 ± 0.179 mg/dL vs 0.823 ± 0.216 mg/dL, P = 0.040), while no significant differences were observed for the other time points (P > 0.05). The length of ICU stay day was significantly shorter in the ulinastatin group (2.91 ± 2.81 day vs 5.22 ± 7.45 day, respectively, P < 0.001). CONCLUSIONS: Ulinastatin did not have a significant effect on the incidence of AKI; it demonstrated the ability to reduce post-operative serum creatine levels at first post-operative day and shorten the length of ICU stay.

Comparison of silicone double-lumen tube and polyvinyl chloride single-lumen tube in fiberoptic tracheal intubation on a difficult airway model: a randomized controlled non-inferiority trial.

The management of patients with history or suspicion of difficult intubation can be challenging, especially in surgical procedures requiring one-lung ventilation. The ease of insertion of silicone double lumen tube (DLT) have previously been shown to be comparable to polyvinyl single lumen tube (SLT) in fiberoptic bronchoscope (FOB) tracheal intubation. Hence, in difficult airway situation, we hypothesized that the performance of insertion of silicone DLT would also be non-inferior to polyvinyl SLT in FOB intubation. We used a neck collar to mimic patients with difficult airway. 80 patients who required one-lung ventilation were enrolled in a prospective, randomized, non-inferiority trial. Patients were randomly allocated to the DLT or SLT groups (SLT with bronchial blocker). Neck collar was supplied to all patients before FOB intubation. The time of insertion for FOB, railroading, tracheal intubation, and total procedure were measured. The difficulty of railroading was evaluated in 4 grades. In the DLT group, the railroading was significantly shorter and easier comparing to the SLT group. The total procedure was also simpler and faster in the DLT group. While simulated difficult airways may not fully replicate actual difficult airways, we suggest that fiberoptic intubation with silicone DLT could be a feasible first-line option for patients with expected difficult airways requiring lung separation, unless the size of the DLT relative to the patient's airway is problematic.Trial registration: NCT03392766.

esRAGE-expressing oHSV enhances anti-tumor efficacy by inhibition of endothelial cell activation.

High-mobility group box 1 (HMGB1) is a damage-associated molecular pattern (DAMP) molecule that plays an important role in inflammation and tumorigenesis. Receptor for advanced glycation end products (RAGE) is one of the major receptors to which extracellular HMGB1 binds to mediate its activity. RAGE is highly expressed on the endothelial cells (ECs) and regulates endothelial permeability during inflammation. Here, we introduced the endogenous secretory form of RAGE (esRAGE) as a decoy receptor for RAGE ligands into an oncolytic herpes simplex virus 1 (oHSV) (OVesRAGE), which, upon release, can function to block RAGE signaling. OVesRAGE significantly decreased phosphorylation of MEK1/2 and Erk and increased cleaved PARP in glioblastoma (GBM) cells in vitro and in vivo. oHSV-infected GBM cells co-cultured with ECs were used to test OVesRAGE effect on EC activation, vessel leakiness, virus replication, and tumor cell killing. OVesRAGE could effectively secrete esRAGE and rescue virus-induced EC migration and activation. Reduced EC activation facilitated virus replication in tumor cells when co-cultured with ECs. Finally, OVesRAGE significantly enhanced therapeutic efficacy in GBM-bearing mice. Collectively, our data demonstrate that HMGB1-RAGE signaling could be a promising target and that its inhibition is a feasible approach to improve the efficacy of oHSV therapy.

Multiple low-dose radiation-induced neuronal cysteine transporter expression and oxidative stress are rescued by N-acetylcysteine in neuronal SH-SY5Y cells.

Recently, several studies have demonstrated that low-dose radiation (LDR) therapy has positively impacts on the treatment of Alzheimer's disease (AD). LDR suppresses the production of pro-neuroinflammation molecules and improves cognitive function in AD. However, it is unclear whether direct exposure to LDR causes beneficial effects and what mechanism is involved in neuronal cells. In this study, we first determined the effect of high-dose radiation (HDR) alone on C6 cells and SH-SY5Y cells. We found that SH-SY5Y cells were more vulnerable than C6 cells to HDR. Moreover, in neuronal SH-SY5Y cells exposed to single or multiple LDR, N-type cells showed decreased cell viability with increasing radiation exposure time and frequency, but S-type cells were unaffected. Multiple LDR increased proapoptotic molecules such as p53, Bax and cleaved caspase-3, and decreased anti-apoptotic molecule (Bcl2). Multiple LDR also generated free radicals in neuronal SH-SY5Y cells. We detected a change in the expression of the neuronal cysteine transporter EAAC1. Pretreatment with N-acetylcysteine (NAC) rescued the increased in EAAC1 expression and the generation of ROS in neuronal SH-SY5Y cells after multiple LDR. Furthermore, we verified whether the increased in EAAC1 expression induces cell defense or cell death promotion signaling. We showed that transient overexpression of EAAC1 reduced the multiple LDR-induced p53 overexpression in neuronal SH-SY5Y cells. Our results indicate that neuronal cells can be injured by increased production of ROS not only by HDR but also by multiple LDR, which suggests that combination treatment with anti-free radical agents such as NAC may be useful in multiple LDR therapy.

Neuregulin-1 reverses anxiety-like behavior and social behavior deficits induced by unilateral micro-injection of CoCl2 into the ventral hippocampus (vHPC).

Neuregulin-1 (NRG1) is an epidermal growth factor family member with essential roles in the developing and adult nervous systems. In recent years, establishing evidence has collectively suggested that NRG1 is a new modulator of central nervous system (CNS) injury and disease, with multifaceted roles in neuroprotection, remyelination, neuroinflammation, and other repair mechanisms. NRG1 signaling exerts its effects via the tyrosine kinase receptors ErbB2-ErbB4. The NRG1/ErbB network in CNS pathology and repair has evolved, primarily in recent years. In the present study, we demonstrated that a unilateral microinjection of CoCl2 into the ventral hippocampus (vHPC) induced hypoxic insult and led to anxiety-related behaviors and deficit sociability in mice. NRG1 treatment significantly alleviated the CoCl2-induced increase of hypoxic-related molecules and behavioral abnormalities. Furthermore, NRG1 reduced the CoCl2-induced neuroinflammation and neuronal deficits in the vHPC or primary hippocampal neurons in mice. Collectively, these results suggest that NRG1 ameliorates hypoxia by alleviating synaptic deficits and behavioral abnormalities of the CoCl2-induced vHPC hypoxic model.

Comparison of fiberoptic bronchoscopic intubation using silicone and polyvinyl chloride double-lumen tubes.

BACKGROUND: Direct insertion of a double-lumen tube (DLT) using a flexible fiberoptic bronchoscope (FOB) is an option for DLT intubation. The difficult process of fiberoptic intubation is that the different properties of polyvinyl chloride and silicone DLTs may affect railroading differently. Therefore, we aimed to compare intubation using polyvinyl chloride and silicone DLTs over an FOB. METHODS: Patients aged 19-75 years who required one-lung ventilation under general anesthesia were enrolled in this study. After induction of anesthesia, the anesthesiologist intubated the DLT using FOB. The primary outcome was the difficulty of railroading over the flexible FOB scaled into five grades (I, II-1, II-2, III, and IV). Additionally, the intubation time and mucosal damage were recorded. RESULTS: A total of 46 patients participated in this study, 23 each in the silicone and polyvinyl groups. The difficulty of railroading over the FOB was significantly different between the two groups (P < 0.001). In the silicone group, the grades of difficulty in railroading were limited to I and II-1; 20 patients (87%) presented no difficulty in advancing the tube. In contrast, in the polyvinyl group, 13 patients (57%) had scores of II-2 and III. Both the intubation time and mucosal damage were significantly better in the silicone group than in the polyvinyl group. CONCLUSIONS: Intubation using a silicone DLT over an FOB was easier and faster than that with a polyvinyl chloride DLT with lesser trauma around the glottis.

Targeting TMEM205 mediated drug resistance in ovarian clear cell carcinoma using oncolytic virus.

BACKGROUND: Ovarian clear cell carcinoma (OCCC) accounts for approximately 8-10% of epithelial ovarian cancers in the United States. Although it is rare, OCCC usually presents with treatment challenges and the overall prognosis is far worse than high grade serous ovarian cancer HGSOC. The objective of this study was to examine the therapeutic relevance of combining oncolytic virus with cisplatin for ovarian cancer clear cell carcinoma (OCCC). RESULTS: We identified that TMEM205, a recently discovered transmembrane protein, contributes to chemoresistance in OCCC cells via the exosomal pathway. Mechanistically, TMEM205 undergoes ligand-independent constitutive endocytosis and co-localizes with Rab11 to contribute to the late recycling endosomes in a clathrin-independent manner. Further, we observed that oncolytic virus (oHSV) pretreatment followed by treatment with cisplatin decreases TMEM205 expression and sensitizes cells to cisplatin in a synergistic manner in OCCC cells. TMEM205 interacts with glycoprotein-C of oHSV post-infection; both of these proteins undergo ubiquitination and ultimately get shuttled outside the cell via exosomes. Thus, we demonstrate the mechanotransduction pathway of TMEM205-mediated chemoresistance along with targeting this pathway using oHSV and cisplatin as a powerful therapeutic strategy for OCCC. oHSV combination with cisplatin inhibits OCCC tumor growth in vivo in immunodeficient and immunocompetent mice models. CONCLUSION: Our results suggest that the combination of oHSV and cisplatin in immunocompetent as well as immune deficient OCCC tumor bearing mice reduces overall tumor burden as well as metastatic disease thereby providing survival benefit. Additionally, the detection of TMEM205 in exosomal cargo early in OCCC development has potential to be exploited as a biomarker.

Inhibiting peripheral and central MAO-B ameliorates joint inflammation and cognitive impairment in rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic inflammation and the destruction of joints and systemic organs. RA is commonly accompanied by neuropsychiatric complications, such as cognitive impairment and depression. However, the role of monoamine oxidase (MAO) and its inhibitors in controlling neurotransmitters associated with these complications in RA have not been clearly identified. Here, we report that peripheral and central MAO-B are highly associated with joint inflammation and cognitive impairment in RA, respectively. Ribonucleic acid (RNA) sequencing and protein expression quantification were used to show that MAO-B and related molecules, such as gamma aminobutyric acid (GABA), were elevated in the inflamed synovium of RA patients. In primary cultured fibroblast-like synoviocytes in the RA synovium, MAO-B expression was significantly increased by tumor necrosis factor (TNF)-α-induced autophagy, which produces putrescine, the polyamine substrate for GABA synthesis. We also observed that MAO-B-mediated aberrant astrocytic production of GABA was augmented by interleukin (IL)-1ß and inhibited CA1-hippocampal pyramidal neurons, which are responsible for memory storage, in an animal model of RA. Moreover, a newly developed reversible inhibitor of MAO-B ameliorated joint inflammation by inhibiting cyclooxygenase (Cox)-2. Therefore, MAO-B can be an effective therapeutic target for joint inflammation and cognitive impairment in patients with RA.

Targeting protein arginine methyltransferase 5 sensitizes glioblastoma to trametinib.

Background: The prognosis of glioblastoma (GBM) remains dismal because therapeutic approaches have limited effectiveness. A new targeted treatment using MEK inhibitors, including trametinib, has been proposed to improve GBM therapy. Trametinib had a promising preclinical effect against several cancers, but its adaptive treatment resistance precluded its clinical translation in GBM. Previously, we have demonstrated that protein arginine methyltransferase 5 (PRMT5) is upregulated in GBM and its inhibition promotes apoptosis and senescence in differentiated and stem-like tumor cells, respectively. We tested whether inhibition of PRMT5 can enhance the efficacy of trametinib against GBM. Methods: Patient-derived primary GBM neurospheres (GBMNS) with transient PRMT5 knockdown were treated with trametinib and cell viability, proliferation, cell cycle progression, ELISA, and western blot were analyzed. In vivo, NSG mice were intracranially implanted with PRMT5-intact and -depleted GBMNS, treated with trametinib by daily oral gavage, and observed for tumor progression and mice survival rate. Results: PRMT5 depletion enhanced trametinib-induced cytotoxicity in GBMNS. PRMT5 knockdown significantly decreased trametinib-induced AKT and ERBB3 escape pathways. However, ERBB3 inhibition alone failed to block trametinib-induced AKT activity suggesting that the enhanced antitumor effect imparted by PRMT5 knockdown in trametinib-treated GBMNS resulted from AKT inhibition and not ERBB3 inhibition. In orthotopic murine xenograft models, PRMT5-depletion extended the survival of tumor-bearing mice, and combination with trametinib further increased survival. Conclusion: Combined PRMT5/MEK inhibition synergistically inhibited GBM in animal models and is a promising strategy for GBM therapy.

The complex relationship between integrins and oncolytic herpes Simplex Virus 1 in high-grade glioma therapeutics.

High-grade gliomas (HGGs) are lethal central nervous system tumors that spread quickly through the brain, making treatment challenging. Integrins are transmembrane receptors that mediate cell-extracellular matrix (ECM) interactions, cellular adhesion, migration, growth, and survival. Their upregulation and inverse correlation in HGG malignancy make targeting integrins a viable therapeutic option. Integrins also play a role in herpes simplex virus 1 (HSV-1) entry. Oncolytic HSV-1 (oHSV) is the most clinically advanced oncolytic virotherapy, showing a superior safety and efficacy profile over standard cancer treatment of solid cancers, including HGG. With the FDA-approval of oHSV for melanoma and the recent conditional approval of oHSV for malignant glioma in Japan, usage of oHSV for HGG has become of great interest. In this review, we provide a systematic overview of the role of integrins in relation to oHSV, with a special focus on its therapeutic potential against HGG. We discuss the pros and cons of targeting integrins during oHSV therapy: while integrins play a pro-therapeutic role by acting as a gateway for oHSV entry, they also mediate the innate antiviral immune responses that hinder oHSV therapeutic efficacy. We further discuss alternative strategies to regulate the dual functionality of integrins in the context of oHSV therapy.

ROR activation by Nobiletin enhances antitumor efficacy via suppression of IκB/NF-κB signaling in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is a heterogeneous disease characterized by poor response to standard therapies and therefore unfavorable clinical outcomes. Better understanding of TNBC and new therapeutic strategies are urgently needed. ROR nuclear receptors are multifunctional transcription factors with important roles in circadian pathways and other processes including immunity and tumorigenesis. Nobiletin (NOB) is a natural compound known to display anticancer effects, and our previous studies showed that NOB activates RORs to enhance circadian rhythms and promote physiological fitness in mice. Here, we identified several TNBC cell lines being sensitive to NOB, by itself or in combination. Cell and xenograft experiments showed that NOB significantly inhibited TNBC cell proliferation and motility in vitro and in vivo. ROR loss- and gain-of-function studies showed concordant effects of the NOB-ROR axis on MDA-MB-231 cell growth. Mechanistically, we found that NOB activates ROR binding to the ROR response elements (RRE) of the IκBα promoter, and NOB strongly inhibited p65 nuclear translocation. Consistent with transcriptomic analysis indicating cancer and NF-κB signaling as major pathways altered by NOB, p65-inducible expression abolished NOB effects, illustrating a requisite role of NF-κB suppression mediating the anti-TNBC effect of NOB. Finally, in vivo mouse xenograft studies showed that NOB enhanced the antitumor efficacy in mammary fat pad implanted TNBC, as a single agent or in combination with the chemotherapy agent Docetaxel. Together, our study highlights an anti-TNBC mechanism of ROR-NOB via suppression of NF-κB signaling, suggesting novel preventive and chemotherapeutic strategies against this devastating disease.

Implications of immune cells in oncolytic herpes simplex virotherapy for glioma.

Despite current progress in treatment, glioblastoma (GBM) remains a lethal primary malignant tumor of the central nervous system. Although immunotherapy has recently achieved remarkable survival effectiveness in multiple malignancies, none of the immune checkpoint inhibitors (ICIs) for GBM have shown anti-tumor efficacy in clinical trials. GBM has a characteristic immunosuppressive tumor microenvironment (TME) that results in the failure of ICIs. Oncolytic herpes simplex virotherapy (oHSV) is the most advanced United States Food and Drug Administration-approved virotherapy for advanced metastatic melanoma patients. Recently, another oHSV, Delytact®, was granted conditional approval in Japan against GBM, highlighting it as a promising treatment. Since oncolytic virotherapy can recruit abundant immune cells and modify the immune TME, oncolytic virotherapy for immunologically cold GBM will be an attractive therapeutic option for GBM. However, as these immune cells have roles in both anti-tumor and anti-viral immunity, fine-tuning of the TME using oncolytic virotherapy will be important to maximize the therapeutic efficacy. In this review, we discuss the current knowledge of oHSV, with a focus on the role of immune cells as friend or foe in oncolytic virotherapy.

NOTCH-Induced MDSC Recruitment after oHSV Virotherapy in CNS Cancer Models Modulates Antitumor Immunotherapy.

PURPOSE: Oncolytic herpes simplex virus-1 (oHSV) infection of brain tumors activates NOTCH, however the consequences of NOTCH on oHSV-induced immunotherapy is largely unknown. Here we evaluated the impact of NOTCH blockade on virus-induced immunotherapy. EXPERIMENTAL DESIGN: RNA sequencing (RNA-seq), TCGA data analysis, flow cytometry, Luminex- and ELISA-based assays, brain tumor animal models, and serum analysis of patients with recurrent glioblastoma (GBM) treated with oHSV was used to evaluate the effect of NOTCH signaling on virus-induced immunotherapy. RESULTS: TCGA data analysis of patients with grade IV glioma and oHSV treatment of experimental brain tumors in mice showed that NOTCH signaling significantly correlated with a higher myeloid cell infiltration. Immunofluorescence staining and RNA-seq uncovered a significant induction of Jag1 (NOTCH ligand) expression in infiltrating myeloid cells upon oHSV infection. Jag1-expressing macrophages further spread NOTCH activation in the tumor microenvironment (TME). NOTCH-activated macrophages increased the secretion of CCL2, which further amplified myeloid-derived suppressor cells. CCL2 and IL10 induction was also observed in serum of patients with recurrent GBM treated with oHSV (rQnestin34.5; NCT03152318). Pharmacologic blockade of NOTCH signaling rescued the oHSV-induced immunosuppressive TME and activated a CD8-dependent antitumor memory response, resulting in a therapeutic benefit. CONCLUSIONS: NOTCH-induced immunosuppressive myeloid cell recruitment limited antitumor immunity. Translationally, these findings support the use of NOTCH inhibition in conjunction with oHSV therapy.

Deep learning for anatomical interpretation of video bronchoscopy images.

Anesthesiologists commonly use video bronchoscopy to facilitate intubation or confirm the location of the endotracheal tube; however, depth and orientation in the bronchial tree can often be confused because anesthesiologists cannot trace the airway from the oropharynx when it is performed using an endotracheal tube. Moreover, the decubitus position is often used in certain surgeries. Although it occurs rarely, the misinterpretation of tube location can cause accidental extubation or endobronchial intubation, which can lead to hyperinflation. Thus, video bronchoscopy with a decision supporting system using artificial intelligence would be useful in the anesthesiologic process. In this study, we aimed to develop an artificial intelligence model robust to rotation and covering using video bronchoscopy images. We collected video bronchoscopic images from an institutional database. Collected images were automatically labeled by an optical character recognition engine as the carina and left/right main bronchus. Except 180 images for the evaluation dataset, 80% were randomly allocated to the training dataset. The remaining images were assigned to the validation and test datasets in a 7:3 ratio. Random image rotation and circular cropping were applied. Ten kinds of pretrained models with < 25 million parameters were trained on the training and validation datasets. The model showing the best prediction accuracy for the test dataset was selected as the final model. Six human experts reviewed the evaluation dataset for the inference of anatomical locations to compare its performance with that of the final model. In the experiments, 8688 images were prepared and assigned to the evaluation (180), training (6806), validation (1191), and test (511) datasets. The EfficientNetB1 model showed the highest accuracy (0.86) and was selected as the final model. For the evaluation dataset, the final model showed better performance (accuracy, 0.84) than almost all human experts (0.38, 0.44, 0.51, 0.68, and 0.63), and only the most-experienced pulmonologist showed performance comparable (0.82) with that of the final model. The performance of human experts was generally proportional to their experiences. The performance difference between anesthesiologists and pulmonologists was marked in discrimination of the right main bronchus. Using bronchoscopic images, our model could distinguish anatomical locations among the carina and both main bronchi under random rotation and covering. The performance was comparable with that of the most-experienced human expert. This model can be a basis for designing a clinical decision support system with video bronchoscopy.

Enpp2 Expression by Dendritic Cells Is a Key Regulator in Migration.

Enpp2 is an enzyme that catalyzes the conversion of lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA), which exhibits a wide variety of biological functions. Here, we examined the biological effects of Enpp2 on dendritic cells (DCs), which are specialized antigen-presenting cells (APCs) characterized by their ability to migrate into secondary lymphoid organs and activate naïve T-cells. DCs were generated from bone marrow progenitors obtained from C57BL/6 mice. Enpp2 levels in DCs were regulated using small interfering (si)RNA or recombinant Enpp2. Expression of Enpp2 in LPS-stimulated mature (m)DCs was high, however, knocking down Enpp2 inhibited mDC function. In addition, the migratory capacity of mDCs increased after treatment with rmEnpp2; this phenomenon was mediated via the RhoA-mediated signaling pathway. Enpp2-treated mDCs showed a markedly increased capacity to migrate to lymph nodes in vivo. These findings strongly suggest that Enpp2 is necessary for mDC migration capacity, thereby increasing our understanding of DC biology. We postulate that regulating Enpp2 improves DC migration to lymph nodes, thus improving the effectiveness of cancer vaccines based on DC.

MicroRNA-138 Increases Chemo-Sensitivity of Glioblastoma through Downregulation of Survivin.

Glioblastoma (GBM) is one of the most deadly cancers and poorly responses to chemotherapies, such as temozolomide (TMZ). Dysregulation of intrinsic signaling pathways in cancer cells are often resulted by dysregulated tumor suppressive microRNAs (miRNAs). Previously, we found miR-138 as one of tumor suppressive miRNAs that were significantly down-regulated in GBM. In this study, we demonstrated that ectopic over-expression of miR-138 sensitizes GBM cells to the treatment of TMZ and increased apoptotic cell death. Mechanistically, miR-138 directly repressed the expression of Survivin, an anti-apoptotic protein, to enhance caspase-induced apoptosis upon TMZ treatment. Using an intracranial GBM xenograft mice model, we also showed that combination of miR-138 with TMZ increases survival rates of the mice compared to the control mice treated with TMZ alone. This study provides strong preclinical evidence of the therapeutic benefit from restoration of miR-138 to sensitize the GBM tumor to conventional chemotherapy.