Hippo pathway inactivation through subcellular localization of NF2/merlin in outer cells of mouse embryos.

The Hippo pathway plays a crucial role in cell proliferation and differentiation during tumorigenesis, tissue homeostasis and early embryogenesis. Scaffold proteins from the ezrin-radixin-moesin (ERM) family, including neurofibromin 2 (NF2; Merlin), regulate the Hippo pathway through cell polarity. However, the mechanisms underlying Hippo pathway regulation via cell polarity in establishing outer cells remain unclear. In this study, we generated artificial Nf2 mutants in the N-terminal FERM domain (L64P) and examined Hippo pathway activity by assessing the subcellular localization of YAP1 in early embryos expressing these mutant mRNAs. The L64P-Nf2 mutant inhibited NF2 localization around the cell membrane, resulting in YAP1 cytoplasmic translocation in the polar cells. L64P-Nf2 expression also disrupted the apical centralization of both large tumor suppressor 2 (LATS2) and ezrin in the polar cells. Furthermore, Lats2 mutants in the FERM binding domain (L83K) inhibited YAP1 nuclear translocation. These findings demonstrate that NF2 subcellular localization mediates cell polarity establishment involving ezrin centralization. This study provides previously unreported insights into how the orchestration of the cell-surface components, including NF2, LATS2 and ezrin, modulates the Hippo pathway during cell polarization.

Associations between early changes in the neutrophil-to-lymphocyte ratio after radical nephroureterectomy and treatment outcomes.

OBJECTIVES: This study explored the impacts of peri-operative changes in the neutrophil-to-lymphocyte ratio (NLR) on the survival rate after radical nephroureterectomy. METHODS: This retrospective analysis included a multicentric cohort of patients diagnosed with upper tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy from 2012 to 2021. We assessed the preoperative NLR, postoperative NLR, delta-NLR (difference between postoperative and preoperative NLRs), and NLR change (ratio of postoperative to preoperative NLR). Additionally, patients were categorized according to increases in their preoperative and/or postoperative NLRs. Associations of survival with peri-operative changes in the NLR were investigated using Cox multivariate regression models. RESULTS: A total of 488 patients were included in the study, with a median age of 73 years. Among the patients, 105 (21.5%) exhibited elevated preoperative and postoperative NLRs, 88 (18.0%) exhibited elevated preoperative NLR only, 53 (10.9%) exhibited elevated postoperative NLR only, and 242 (49.6%) exhibited normal NLRs. Multivariate analysis indicated significant negative correlations between both preoperative and postoperative increased NLRs and oncological outcomes, including nonurothelial tract recurrence-free survival and cancer-specific survival (hazard ratio [HR]: 1.65, P = 0.017; HR: 2.12, P = 0.014, respectively). CONCLUSION: This is the first study to evaluate the association between peri-operative changes in the NLR and the outcomes of patients with UTUC who underwent radical nephroureterectomy. Patients with elevated NLRs at both time points experienced considerably worse outcomes. Further research should explore whether increases in the NLR during long-term follow-up could indicate impending disease recurrence.

3-Hydroxy-3-(2-oxopropyl)indolin-2-one, a product of a human-derived Enterocloster strain, is an inhibitor of nitric oxide production.

When cultured anaerobically, Enterocloster sp. RD014215 was found to produce 1. Using nuclear magnetic resonance and mass spectroscopy, the planar structure of 1 was determined to be 3-hydroxy-3-(2-oxopropyl)indolin-2-one. The chirality of 1 was implied as S by comparing the optical rotation value of 1 with literature reports of the synthesized compounds. To our knowledge, this work represents the first discovery of the metabolite produced by Enterocloster strain. 1 exhibited inhibition of nitric oxide (NO) production, demonstrating a 50% inhibitory activity (IC50) of 34 µm for NO production by murine macrophage cells subjected to lipopolysaccharide stimulation.

Effectiveness and safety of enzalutamide and apalutamide in the treatment of patients with non-metastatic castration-resistant prostate cancer (nmCRPC): a multicenter retrospective study.

OBJECTIVE: Phase III clinical trials demonstrated the efficacy of enzalutamide and apalutamide in patients with non-metastatic castration-resistant prostate cancer (nmCRPC) and PSA doubling time ≤10 months. Although these drugs have been shown to vary in their adverse event (AE) profiles, the differences in their efficacy profiles remain to be evaluated. Therefore, this retrospective study was conducted to evaluate the efficacy of these drugs in patients with nmCRPC. METHODS: This study evaluated 191 patients with nmCRPC treated with enzalutamide (n = 137) or apalutamide (n = 54) in the first-line setting at Jikei University Hospital or its affiliated hospitals between May 2014 and November 2022. Endpoints were defined as oncological outcomes (i.e., PSA response, PFS, PSA-PFS, MFS, CSS, and OS) and AEs. RESULTS: No significant differences were noted in patient backgrounds between the two groups. Patients exhibiting a maximum PSA response of >50% and >90% accounted for 74.5% and 48.9% of patients in the enzalutamide group, and 75.9% and 42.6% of patients in the apalutamide group, respectively, with no significant difference between the groups. The median PSA-PFS was 10 months in the enzalutamide group but not in the apalutamide group, with no significant difference between the groups (P = 0.48). No significant differences were observed in MFS, CSS, or OS between the groups. Patients reporting AEs of all grades and grade 3 or higher accounted for 56.2% and 4.3% of those in the enzalutamide group and 57.4% and 7.4% of those in the apalutamide group, respectively. The most common AE was fatigue (26.3%) in the enzalutamide group and skin rash (27.8%) in the apalutamide group. CONCLUSION: In this retrospective study of their efficacy and safety, enzalutamide and apalutamide were shown to exhibit comparable oncological outcomes but quite different AE profiles, suggesting that their differential use may be warranted based on these findings.

Real-world outcomes of adjuvant immunotherapy candidates with upper tract urothelial carcinoma: results of a multicenter cohort study.

BACKGROUND: Recent clinical trials have reported improved disease-free survival rates of patients with stage pT3-4/ypT2-4 or pN + upper tract urothelial carcinoma (UTUC) on adjuvant nivolumab therapy. However, the appropriateness of the patient selection criteria used in clinical practice remains uncertain. METHODS: We retrospectively analyzed 895 patients who underwent nephroureterectomy to treat UTUC. The patients were divided into two groups: grade pT3-4 and/or pN + without neoadjuvant chemotherapy (NAC) or grade ypT2-4 and/or ypN + on NAC (adjuvant immunotherapy candidates) and others (not candidates for adjuvant immunotherapy). Kaplan-Meier curves were drawn to assess the oncological outcomes, including recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS). Cox proportional hazards models were used to identify significant prognostic factors for oncological outcomes. RESULTS: The Kaplan-Meier curves revealed notably inferior RFS, CSS, and OS of patients who were candidates for adjuvant immunotherapy. Multivariate analysis revealed that pathological T and N grade and lymphovascular invasion (LVI) status were independent risk factors for poor RFS, CSS, and OS. CONCLUSION: In total, 44.8% of patients were candidates for adjuvant immunotherapy. In addition to pathological T and N status, LVI was a significant predictor of survival, and may thus play a pivotal role in the selection of patients eligible for adjuvant immunotherapy.

Methodology for awakening the potential secondary metabolic capacity in actinomycetes.

Secondary metabolites produced by actinomycete strains undoubtedly have great potential for use in applied research areas such as drug discovery. However, it is becoming difficult to obtain novel compounds because of repeated isolation around the world. Therefore, a new strategy for discovering novel secondary metabolites is needed. Many researchers believe that actinomycetes have as yet unanalyzed secondary metabolic activities, and the associated undiscovered secondary metabolite biosynthesis genes are called "silent" genes. This review outlines several approaches to further activate the metabolic potential of actinomycetes.

Avian retroviral cardiomyopathy induced by infectious molecular clones of avian leukosis viruses (fowl glioma-inducing virus variants).

We previously described cardiomyocyte abnormality caused by Km_5666 strain, a variant of fowl glioma-inducing virus (FGV) prototype, which is an avian leukosis virus (ALV). However, the cardiac involvement appeared to be eradicated from the flock after a few years. An epidemiological survey from 2017 to 2020 was performed to elucidate the current prevalence of the cardiopathogenic strains in this flock. Four of the 71 bantams pathologically examined showed both glioma and cardiomyocyte abnormality, from which three ALV strains were detected. DNA sequencing revealed that several different ALV strains coexisted in each bantam and that the conserved Km_5666 virus fluid also contained at least two different ALV strains. We generated three infectious molecular clones from these samples, named KmN_77_clone_A, KmN_77_clone_B, and Km_5666_clone. The envSU of KmN_77_clone_A shared high sequence identity with that of Km_5666 (94.1%). In contrast, the envSU of KmN_77_clone_B showed >99.2% nucleotide similarity with that of an FGV variant without cardiopathogenicity. Furthermore, Km_5666_clone experimentally reproduced both gliomas and cardiomyocyte abnormality in chickens. From these results, it is suggested that the pathogenic determinant of cardiomyocyte abnormality is located in envSU similar to that of Km_5666. The cloning technique described here is beneficial for evaluating the viral pathogenicity in cases where affected birds are coinfected with several different ALV strains.

Domain Localization by Graphene Oxide in Supported Lipid Bilayers.

The gel-phase domains in a binary supported lipid bilayer (SLB) comprising dioleoylphosphatidylcholine (DOPC) and dipalmitoylphosphatidylcholine (DPPC) were localized on graphene oxide (GO) deposited on a SiO2/Si substrate. We investigated the distribution of the gel-phase domains and the liquid crystalline (Lα) phase regions in DOPC+DPPC-SLB on thermally oxidized SiO2/Si substrates with GO flakes to understand the mechanism of the domain localization on GO. Fluorescence microscopy and atomic force microscopy revealed that the gel-phase domains preferably distributed on GO flakes, whereas the fraction of the Lα-phase increased on the bare SiO2 surface which was not covered with the GO flakes. The gel-phase domain was condensed on GO more effectively at the lower cooling rate. We propose that nucleation of the gel-phase domain preferentially occurred on GO, whose surface has amphiphilic property, during the gel-phase domain formation. The domains of the liquid ordered (Lo) phase were also condensed on GO in a ternary bilayer containing cholesterol that was phase-separated to the Lo phase and the liquid disordered phase. Rigid domains segregates on GO during their formation process, leaving fluid components to the surrounding region of GO.

Deciphering two rounds of cell lineage segregations during bovine preimplantation development.

Blastocyst formation gives rise to the inner cell mass (ICM) and trophectoderm (TE) and is followed by the differentiation of the epiblast (Epi) and primitive endoderm (PrE) within the ICM. Although these two-round cell lineage differentiations underpin proper embryogenesis in every mammal, their spatiotemporal dynamics are quite diverse among species. Here, molecular details of the blastocyst stage in cattle were dissected using an optimized in vitro culture method. Blastocyst embryos were placed on agarose gel filled with nutrient-rich media to expose embryos to both gaseous and liquid phases. Embryos derived from this "on-gel" culture were transferred to surrogate mothers on day (D) 10 after fertilization and successfully implanted. Immunofluorescent studies using on-gel-cultured embryos revealed that the proportion of TE cells expressing the pluripotent ICM marker, OCT4, which was beyond 80% on D8, was rapidly reduced after D9 and reached 0% on D9.5. This first lineage segregation process was temporally parallel with the second one, identified by the spatial separation of Epi cells expressing SOX2 and PrE cells expressing SOX17. RNA-seq comparison of TE cells from D8 in vitro fertilized embryos and D14 in vivo embryos revealed that besides drastic reduction of pluripotency-related genes, TE cells highly expressed Wnt, FGF, and VEGF signaling pathways-related genes to facilitate the functional maturation required for feto-maternal interaction. Quantitative PCR analysis of TE cells derived from on-gel culture further confirmed time-dependent increments in the expression of key TE markers. Altogether, the present study provides platforms to understand species-specific strategies for mammalian preimplantation development.

Phytohabitols A-C, δ-Lactone-Terminated Polyketides from an Actinomycete of the Genus Phytohabitans.

Phytohabitols A-C (1-3), new terminally δ-lactonized linear polyketides, were isolated from the culture extract of a rare actinomycete of the genus Phytohabitans. The structures of 1-3, substituted with multiple methyl and hydroxy groups on a conjugated and a skipped diene-containing backbone, were elucidated by NMR and MS spectroscopic analyses. The absolute configuration of 1 was determined by chemical derivatization and chiral anisotropic analysis, coupled with ROESY and J-based configuration analysis. In addition, closely similar 1H and 13C NMR data and optical rotations among 1-3 supported the same stereochemistry of these polyketides. The related streptomycetes metabolites lagunapyrones B, C, and D have α-pyrone rings on the linear part in place of the δ-lactone, but their chirality at the C19-C21 stereocenters were opposite from those described here, posing a question on the previous assignment made solely by comparison of the optical rotations of four possible diastereomers. Compounds 1-3 inhibited migration of cancer cells with IC50 values of 15, 11, and 8.3 µM, respectively, at noncytotoxic concentrations. In addition, 1-3 displayed potent antitrypanosomal activity against Trypanosoma cruzi with IC50 values of 12, 6.4, and 18 µM, comparable to a commonly used therapeutic drug, benznidazole (IC50 16 µM).

Dihydromaniwamycin E, a Heat-Shock Metabolite from Thermotolerant Streptomyces sp. JA74, Exhibiting Antiviral Activity against Influenza and SARS-CoV-2 Viruses.

Dihydromaniwamycin E (1), a new maniwamycin derivative featuring an azoxy moiety, has been isolated from the culture extract of thermotolerant Streptomyces sp. JA74 along with the known analogue maniwamycin E (2). Compound 1 is produced only by cultivation of strain JA74 at 45 °C, and this type of compound has been previously designated a "heat shock metabolite (HSM)" by our research group. Compound 2 is detected as a production-enhanced metabolite at high temperature. Structures of 1 and 2 are elucidated by NMR and MS spectroscopic analyses. The absolute structure of 1 is determined after the total synthesis of four stereoisomers. Though the absolute structure of 2 has been proposed to be the same as the structure of maniwamycin D, the NMR and the optical rotation value of 2 are in agreement with those of maniwamycin E. Therefore, this study proposes a structural revision of maniwamycins D and E. Compounds 1 and 2 show inhibitory activity against the influenza (H1N1) virus infection of MDCK cells, demonstrating IC50 values of 25.7 and 63.2 µM, respectively. Notably, 1 and 2 display antiviral activity against SARS-CoV-2, the causative agent of COVID-19, when used to infect 293TA and VeroE6T cells, with 1 and 2 showing IC50 values (for infection of 293TA cells) of 19.7 and 9.7 µM, respectively. The two compounds do not exhibit cytotoxicity in these cell lines at those IC50 concentrations.

Generation of viable calves derived from developmentally mature blastocysts produced by on-gel culture.

Conventional culture systems for bovine embryos are unable to support sustained embryonic development until the developmentally mature blastocyst stage. Although we have previously developed an on-gel culture system that enables bovine blastocysts to complete cell segregation events at day (D) 10 following in vitro culture, the development of D10 blastocysts to term has yet to be achieved. In this study, we attained full-term development of D10 mature blastocysts produced using an on-gel culture system. Two calves derived from on-gel-cultured embryos were vaginally born, showing normal birth and placental weights and no obvious morphological abnormalities. Moreover, we detected no abnormalities in blood metabolic profile analyses. Our findings indicate that on-gel culturing can be used to facilitate the development of developmentally mature blastocysts to term, and produce healthy viable calves. This culture system could make a valuable contribution to cattle production and would enable a range of analyses for characterizing bovine-specific pre-implantation development.

Requirement for expression of WW domain containing transcription regulator 1 in bovine trophectoderm development.

WW domain-containing transcription regulator 1 (WWTR1) is one of the primary effectors in the Hippo pathway, which plays essential roles in cell differentiation into trophectoderm (TE) and inner cell mass cell lineages at the blastocyst stage. However, little is known about the roles of WWTR1 in preimplantation development. The present study aimed to explore the significance of WWTR1 expression in preimplantation development using an mRNA knockdown (KD) system in bovine embryos. We first quantitated WWTR1 expression at protein and mRNA levels from fertilization to blastocyst stage. WWTR1 proteins gradually shifted from extranuclear localization during the 16-cell stage to nuclear localization by morula stage. WWTR1 mRNA expression was also transiently upregulated at the 16-cell stage. WWTR1 KD efficiently repressed WWTR1 expression at protein and mRNA levels. The WWTR1 KD embryos developed to the blastocyst stage at rates equivalent to those of controls, but TE cell numbers were significantly decreased. Representative TE-expressed genes, including CDX2 and IFNT were also significantly decreased in WWTR1 KD blastocysts. These results provide the first demonstration that WWTR1 expression is responsible for normal TE cell development in preimplantation embryos.

Trimodal therapy with high-dose-rate brachytherapy and hypofractionated external beam radiation combined with long-term androgen deprivation for unfavorable-risk prostate cancer.

PURPOSE: To assess the outcomes of high-dose-rate (HDR) brachytherapy and hypofractionated external beam radiation therapy (EBRT) combined with long-term androgen deprivation therapy (ADT) in very-high-risk (VHR) versus high-risk (HR) prostate cancer (PCa), as defined in the National Comprehensive Cancer Network (NCCN) criteria. METHODS: Data from 338 consecutive HR or VHR PCa patients who had undergone this tri-modal therapy between 2005 and 2018 were retrospectively analyzed. Biochemical recurrence (BCR)-free, progression-free, overall, and cancer-specific survival (BCRFS/PFS/OS/CSS) rates were analyzed using the Kaplan-Meier method and Wilcoxon test. Cox regression models were used to evaluate candidate prognostic factors for survival. C­indexes were used to assess model discrimination. RESULTS: Within a median follow-up of 84 months, 68 patients experienced BCR, 58 had disease progression including only 3 with local progression, 27 died of any cause, and 2 died from PCa. The 5­year BCRFS, PFS, OS, and CSS rates were 82.2% (HR 86.5%; VHR 70.0%), 90.0% (HR 94.3%; VHR 77.6%), 95.7% (HR, 97.1%; VHR, 91.8%), and 99.6% (HR, 100%; VHR, 98.0%), respectively. In multivariable analyses that adjusted for standard clinicopathologic features, the risk subclassification was associated both PFS and OS (p = 0.0003 and 0.001, respectively). Adding the risk subclassification improved the accuracy of models in predicting BCRFS, PFS, and OS. CONCLUSION: While the outcome of this trimodal approach appears favorable, VHR PCa patients had significantly worse oncological outcomes than those with HR PCa. The NCCN risk subclassification should be integrated into prognostic tools to guide risk stratification, treatment, and follow-up for unfavorable PCa patients receiving this trimodal therapy.

Unsaturated fatty acids and a prenylated tryptophan derivative from a rare actinomycete of the genus Couchioplanes.

A genome mining survey combined with metabolome analysis of publicly available strains identified Couchioplanes sp. RD010705, a strain belonging to an underexplored genus of rare actinomycetes, as a producer of new metabolites. HPLC-DAD-guided fractionation of its fermentation extracts resulted in the isolation of five new methyl-branched unsaturated fatty acids, (2E,4E)-2,4-dimethyl-2,4-octadienoic acid (1), (2E,4E)-2,4,7-trimethyl-2,4-octadienoic acid (2), (R)-(-)-phialomustin B (3), (2E,4E)-7-hydroxy-2,4-dimethyl-2,4-octadienoic acid (4), (2E,4E)-7-hydroxy-2,4,7-trimethyl-2,4-octadienoic acid (5), and one prenylated tryptophan derivative, 6-(3,3-dimethylallyl)-N-acetyl-ʟ-tryptophan (6). The enantiomer ratio of 4 was determined to be approximately S/R = 56:44 by a recursive application of Trost's chiral anisotropy analysis and chiral HPLC analysis of its methyl ester. Compounds 1-5 were weakly inhibitory against Kocuria rhizophila at MIC 100 µg/mL and none were cytotoxic against P388 at the same concentration.

Nomimicins B-D, new tetronate-class polyketides from a marine-derived actinomycete of the genus Actinomadura.

Three new tetronate-class polyketides, nomimicins B, C, and D, along with nomimicin, hereafter named nomimicin A, were isolated from the culture extract of Actinomadura sp. AKA43 collected from floating particles in the deep-sea water of Sagami Bay, Japan. The structures of nomimicins B, C, and D were elucidated through the interpretation of NMR and MS analytical data, and the absolute configuration was determined by combination of NOESY/ROESY and ECD analyses. Nomimicins B, C, and D showed antimicrobial activity against Gram-positive bacteria, Kocuria rhizophila and Bacillus subtilis, with MIC values in the range of 6.5 to 12.5 µg/mL. Nomimicins B and C also displayed cytotoxicity against P388 murine leukemia cells with IC50 values of 33 and 89 µM, respectively.

A cyclopeptide and three oligomycin-class polyketides produced by an underexplored actinomycete of the genus Pseudosporangium.

Aside from the well-studied conventional actinomycetes such as Streptomyces, the less investigated genera of actinomycetes also represent a promising source of natural products. Genome mining indicated that members of the underexplored genus Pseudosporangium, from which no secondary metabolites have been reported to date, may harbor the biosynthetic machinery for the formation of novel natural products. The strain RD062863, that is available at a public culture collection, was obtained and subjected to metabolite analysis, which resulted in the discovery of a novel cyclopeptide, pseudosporamide (1), along with three new oligomycin-class polyketides, pseudosporamicins A-C (2-4). The unusual structure of compound 1, featured by a biaryl-bond bridging across a tripeptide scaffold, N-acetyl-ʟ-Tyr-ʟ-Pro-ʟ-Trp, was determined by a combination of spectroscopic analyses, chemical derivatization, ECD calculation, and DFT-based theoretical chemical shift calculation, revealing the presence of an (S a)-axial chirality around the biaryl bond. Compounds 2-4 lacked hydroxylation on the side chain of the spiroacetal rings, which showed clear contrast to other oligomycin congeners and related polyketides with ring-truncation or expansion. The new macrolides 2-4 displayed potent antimicrobial activity against the Gram-positive bacterium Kocuria rhizohpila and the plant pathogenic fungus Glomerella cingulata. All compounds showed moderate cytotoxicity against P388 murine leukemia cells with IC50 values in the micromolar to submicromolar ranges. These results exemplified the validity of phylogeny-focused strain selection combined with biosynthetic gene-directed genome mining for the efficient discovery of new natural products.

Stereoselective ozonolysis of TMS-substituted allylic alcohol derivatives and synthesis of 14R,15S- and 14S,15S-diHETE.

Ozonolysis of TMS-substituted olefins produces α-carbonyl TMS peroxides without cleavage of the C[double bond, length as m-dash]C bond. Herein, stereochemistry in the ozonolysis was studied using silyl derivatives of (E)- and (Z)-(1-TMS)alk-1-en-3-ols. The (E)-isomers afforded the anti-3-siloxy-2-(TMS-oxy)aldehydes as the major stereoisomer (anti/syn = 3-9 : 1) after reductive work-up with Ph3P. In contrast, Z-olefins selectively gave the syn isomers with syn/anti ratios of 4-19 : 1. Facial selection was speculated based on the Cieplak effect. This ozonolysis was successfully applied for the synthesis of 14R,15S- and 14S,15S-diHETEs (anti and syn isomers, respectively) in enantioenriched forms.

Biological activities of unique isoflavones prepared from Apios americana Medik.

Four unique isoflavone aglycones (barpisoflavone A (1), 2'-hydroxygenistein (2), 5-methylgenistein (3), and gerontoisoflavone A (4)) whose structures were related to genistein were prepared from the tuber of Apios americana Medik. We examined the estrogen receptor and androgen receptor binding activities, estrogen agonistic activities, antioxidant activities, and α-glucosidase inhibitory activities of 1-4. The results obtained showed that 2 possessed potent and 1, 3, and 4 possessed moderate estrogen partial agonistic activities, 1 and 2 possessed moderate antioxidant activities, and 2 and 3 possessed moderate α-glucosidase inhibitory activities.

[Early Detection of Iliac Artery Rupture by Sudden Steep Reduction of Regional Saturation of Oxygen at the Ipsilateral Foot during Transcatheter Aortic Valve Implantation--A Case Report].

An 80-year-old woman with severe aortic stenosis was planned to undergo transcatheter aortic valve implantation (TAVI) under general anesthesia. Due to severe stenosis of the femoral arteries, the left iliac artery was cut down and a 16 F Edwards SAPIEN Expandable Sheath (eSheath : Edwards Lifesciences, Irvine, CA) was inserted into the artery smoothly. After balloon aortic valvuloplasty (BAV), an artificial valve was tried to deploy but stuck in the middle of eSheath. Suddenly regional saturation of oxygen (rSO2) at the ipsilateral foot decreased steeply without other significant hemodynamic instabilities. At insertion site of eSheath, the left external iliac artery rupture occurred. To our surprise, there was almost no major bleeding because of the artery spasm and suppression of the large bore sheath. eSheath and the stuck valve were taken out together and TAVI was discontinued. The artery was replaced with a graft, and rSO2 of the foot recovered. Her aortic stenosis improved to moderate by balloon aortic valvuloplasty (BAV) according to transthoracic echocardiography. The patient was discharged on foot without complications. To our knowledge, this is a first report of a silent rupture of the iliac artery during TAVI to be detected by sudden decrease of the foot rSO2 and treated with no fatal events.