RESUMO
In this study, we report the synthesis of 2'-formamidonucleoside phosphoramidite derivatives and their incorporation into siRNA strands to reduce seed-based off-target effects of small interfering RNAs (siRNAs). Formamido derivatives of all four nucleosides (A, G, C and U) were synthesized in 5-11 steps from commercial compounds. Introducing these derivatives into double-stranded RNA slightly reduced its thermodynamic stability, but X-ray crystallography and CD spectrum analysis confirmed that the RNA maintained its natural A-form structure. Although the introduction of the 2'-formamidonucleoside derivative at the 2nd position in the guide strand of the siRNA led to a slight decrease in the on-target RNAi activity, the siRNAs with different sequences incorporating 2'-formamidonucleoside with four kinds of nucleobases into any position other than 2nd position in the seed region revealed a significant suppression of off-target activity while maintaining on-target RNAi activity. This indicates that 2'-formamidonucleosides represent a promising approach for mitigating off-target effects in siRNA therapeutics.
RESUMO
BACKGROUND: Bmal1 (Brain and muscle arnt-like, or Arntl) is a bHLH/PAS domain transcription factor central to the transcription/translation feedback loop of the circadian clock. Mast cells are crucial for effector functions in allergic reaction and their activity follows a circadian rhythm. However, the functional roles of Bmal1 in mast cells remain to be determined. PURPOSE: This study aimed to elucidate the specific roles of Bmal1 in IgE-dependent mast cell degranulation. RESULTS: IgE-dependent degranulation was enhanced in bone marrow-derived mast cells (BMMCs) derived from Bmal1-deficient mice (Bmal1-KO mice) compared to that in BMMCs derived from wild-type mice (WT mice) in the absence of 2-Mercaptoethanol (2-ME) in culture. Mast cell-deficient KitW-sh mice reconstituted with Bmal1-KO BMMCs showed more robust passive cutaneous anaphylactic (PCA) reactions, an in vivo model of IgE-dependent mast cell degranulation, than KitW-sh mice reconstituted with WT BMMCs. In the absence of 2-ME in culture, the mRNA expression of the anti-oxidative genes NF-E2-related factor 2 (Nrf2), superoxide dismutase 2 (SOD2), and heme oxygenase-1 (HO-1) was lower and reactive oxygen species (ROS) generation was higher in Bmal1-KO BMMCs than in WT BMMCs at steady state. The IgE-dependent ROS generation and degranulation were enhanced in Bmal1-KO BMMCs compared to WT BMMCs in the absence of 2-ME in culture. The addition of 2-ME into the culture abrogated or weakened the differences in anti-oxidative gene expression, ROS generation, and IgE-dependent degranulation between WT and Bmal1-KO BMMCs. CONCLUSION: The current findings suggest that Bmal1 controls the expression of anti-oxidative genes in mast cells and Bmal1 deficiency enhanced IgE-dependent degranulation associated with promotion of ROS generation. Thus, Bmal1 may function as a key molecule that integrates redox homeostasis and effector functions in mast cells.
Assuntos
Fatores de Transcrição ARNTL , Mastócitos , Animais , Camundongos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Degranulação Celular , Imunoglobulina E/metabolismo , Mastócitos/metabolismo , Mercaptoetanol/metabolismo , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismoRESUMO
Ethyl caffeate (EC) is a natural phenolic compound that is present in several medicinal plants used to treat inflammatory disorders. However, its anti-inflammatory mechanisms are not fully understood. Here, we report that EC inhibits aryl hydrocarbon receptor (AhR) signaling and that this is associated with its anti-allergic activity. EC inhibited AhR activation, induced by the AhR ligands FICZ and DHNA in AhR signaling-reporter cells and mouse bone marrow-derived mast cells (BMMCs), as assessed by AhR target gene expressions such as CYP1A1. EC also inhibited the FICZ-induced downregulation of AhR expression and DHNA-induced IL-6 production in BMMCs. Furthermore, the pretreatment of mice with orally administered EC inhibited DHNA-induced CYP1A1 expression in the intestine. Notably, both EC and CH-223191, a well-established AhR antagonist, inhibited IgE-mediated degranulation in BMMCs grown in a cell culture medium containing significant amounts of AhR ligands. Furthermore, oral administration of EC or CH-223191 to mice inhibited the PCA reaction associated with the suppression of constitutive CYP1A1 expression within the skin. Collectively, EC inhibited AhR signaling and AhR-mediated potentiation of mast cell activation due to the intrinsic AhR activity in both the culture medium and normal mouse skin. Given the AhR control of inflammation, these findings suggest a novel mechanism for the anti-inflammatory activity of EC.
Assuntos
Mastócitos , Receptores de Hidrocarboneto Arílico , Camundongos , Animais , Receptores de Hidrocarboneto Arílico/metabolismo , Mastócitos/metabolismo , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Ligantes , Anti-Inflamatórios/metabolismoRESUMO
OBJECTIVE: Recent studies suggest that the knee is frequently involved in PMR. In this study, we aimed to determine whether the US assessment of the shoulder and knee discriminates between PMR and other differential diagnoses and improves the accuracy of the 2012 EULAR/ACR provisional classification criteria for PMR. METHODS: We consecutively enrolled 81 untreated patients who received a diagnosis of PMR. These patients were divided into two groups based on the final diagnosis made at 1-year follow-up: PMR-definite group (n = 60) and PMR-mimic group (n = 21). We also enrolled age/sex-matched untreated RA patients with shoulder pain from an independent cohort (RA group, n = 60). All patients underwent comprehensive US assessment of the shoulder and knee for synovitis, bursitis, tenosynovitis, tendinitis and ligament inflammation at baseline. RESULTS: US scores for tenosynovitis, tendinitis and ligament inflammation better discriminated the PMR-definite group from the PMR-mimic and RA groups than do those for synovitis or bursitis. Among logistic regression models to identify US variables that were associated with the PMR-definite group, the best fitted model included two US variables: the bilateral involvement of the shoulder (long head of biceps, supraspinatus or subscapularis tendon) and the bilateral involvement of the knee (popliteus tendon or medial or lateral collateral ligament). Incorporating these two items into the 2012 EULAR/ACR provisional classification criteria numerically increased the accuracy to classify the PMR-definite group. CONCLUSION: US assessment of the tendon/ligament-related lesions in the shoulder and knee may improve the accuracy of the 2012 EULAR/ACR provisional classification criteria for PMR.
Assuntos
Articulação do Joelho/diagnóstico por imagem , Polimialgia Reumática/classificação , Polimialgia Reumática/diagnóstico por imagem , Articulação do Ombro/diagnóstico por imagem , Ultrassonografia , Idoso , Idoso de 80 Anos ou mais , Feminino , Glucocorticoides/uso terapêutico , Humanos , Masculino , Polimialgia Reumática/tratamento farmacológicoRESUMO
The medicinal applications of siRNAs have been intensively examined but are still hindered by their low molecular stability under biological conditions and off-target effects, etc. The introduction of chemical modifications to the nucleoside is a promising strategy for solving these limitations. Herein, we describe the development of a new uridine analog, U*, that has a (methylthiomethoxy)methoxy group at the 2' position. The phosphoramidite reagent corresponding to U* was easily synthesized and the RNA oligonucleotides containing U* were stably prepared using a standard protocol for oligonucleotide synthesis. The introduction of U* into the siRNA resulted in positive or negative effects on the targeted gene silencing in a position-dependent manner, and the positive effects were attributed to the improved stability under biological conditions. The thermodynamic analysis of the U*-modified RNAs revealed a slight destabilization of the dsRNA, based depending on which U was strategically utilized to restrain the off-target effects of the siRNA. This study describes a rare example of nucleoside analogs with a large substitution at the 2'-position in the context of an siRNA application and is informative for the development of other analogs to further improve the molecular properties of siRNAs for medicinal applications.
Assuntos
Inativação Gênica , Oligonucleotídeos , Nucleosídeos , Oligonucleotídeos/química , RNA Interferente Pequeno/química , Termodinâmica , Uridina/químicaRESUMO
Inorganic nanomaterials such as nanotubes and nanorods have attracted great attention due to their anisotropic properties. Although the alignment control of inorganic nanomaterials is key to the development of functional devices utilizing their fascinating properties, there is still difficulty in achieving uniform alignment over a large area with a micrometer thickness. To overcome this problem, we focused on liquid crystals (LCs) to promote the alignment of anisotropic nanomaterials, taking advantage of the cooperative motion of LCs. We present the uniform, one-dimensional alignment of ZnO nanorods along the direction of LCs in micrometer-thick cells by grafting nematic LC polymers from the nanorod surfaces to provide miscibility with the host LCs. Polarized optical microscopy and polarized UV-visible absorption spectroscopy revealed the unidirectional alignment of nematic LC polymer-grafted ZnO nanorods parallel to the nematic host LCs.
RESUMO
OBJECTIVES: This study researched the efficacy of rituximab (RTX) in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated hypertrophic pachymeningitis (HP). METHODS: Eight patients were identified by retrospective chart review from local registries at four hospitals in Japan. All patients met the Chapel Hill 2012 Consensus Conference definitions of ANCA-associated vasculitis and had disease complicated with HP. We assessed the dose of glucocorticoids, C-reactive protein (CRP) levels, Birmingham vasculitis activity score (BVAS) and contrast-enhanced magnetic resonance imaging (MRI) findings of HP before and after RTX administration. RESULTS: Three of eight patients were female. The median age was 68 years. No patients had HP at onset of vasculitis. Two patients had a relapse of HP before RTX administration. RTX was used as the initial treatment for HP in three patient. The daily dose of glucocorticoids, CRP levels and BVAS decreased from baseline to 6 months after RTX treatment in all patients. Evaluation of HP by contrast-enhanced MRI showed improvement in seven of eight cases. All of seven patients achieved sustained remission at 6 months after RTX treatment. No serious adverse events were observed in any patient. CONCLUSIONS: Our case series highlights the efficacy of RTX in patients with difficult-to-treat ANCA-associated HP. Future prospective studies are warranted to establish B-cell depletion therapy by RTX as a treatment option for ANCA-associated HP.
Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Meningite/terapia , Rituximab/uso terapêutico , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Anticorpos Anticitoplasma de Neutrófilos , Feminino , Humanos , Japão , Masculino , Meningite/complicações , Indução de Remissão , Estudos Retrospectivos , Resultado do TratamentoRESUMO
MicroRNAs (miRNAs) are small non-coding RNAs that play essential roles in the regulation of gene function by a mechanism known as RNA silencing. In a previous study, we revealed that miRNA-mediated silencing efficacy is correlated with the combinatorial thermodynamic properties of the miRNA seed-target mRNA duplex and the 5´-terminus of the miRNA duplex, which can be predicted using 'miScore'. In this study, a robust refined-miScore was developed by integrating the thermodynamic properties of various miRNA secondary structures and the latest thermodynamic parameters of wobble base-pairing, including newly established parameters for I:C base pairing. Through repeated random sampling and machine learning, refined-miScore models calculated with either melting temperature (Tm) or free energy change (ΔG) values were successfully built and validated in both wild-type and adenosine-to-inosine edited miRNAs. In addition to the previously reported contribution of the seed-target duplex and 5´-terminus region, the refined-miScore suggests that the central and 3´-terminus regions of the miRNA duplex also play a role in the thermodynamic regulation of miRNA-mediated silencing efficacy.
Assuntos
Adenosina , Substituição de Aminoácidos , Inosina , MicroRNAs/genética , Modelos Biológicos , Edição de RNA , Interferência de RNA , Algoritmos , Aprendizado de Máquina , Conformação de Ácido Nucleico , Estabilidade de RNA , RNA Mensageiro/genética , TermodinâmicaAssuntos
Lúpus Eritematoso Sistêmico , Trombocitopenia , Humanos , Rituximab/uso terapêutico , Glucocorticoides/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Imunossupressores , Trombocitopenia/tratamento farmacológico , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Resultado do TratamentoRESUMO
The base-promoted α-alkylation of N-((S)-1-phenylethyl)azetidine-2-carboxylic acid esters 1 was investigated. The use of diastereomerically pure borane complexes 3 as substrates, which are easily prepared from 1, dramatically improved the yields and diastereoselectivities of α-alkylated products 2. For example, the treatment of tert-butyl ester (1S,2S,1'S)-3a with 2.4 equivalents of lithium bis(trimethysilyl)amide (LiHMDS) at 0 °C followed by 2.6 equivalents of benzyl bromide afforded α-benzylated (2S,1'S)-2aa in 90% yield as almost a single diastereomer. Our method enables the production of optically active α-substituted azetidine-2-carboxylic acid esters starting from commercially available (S)-1-phenylethylamine, which is one of the least expensive chiral compounds.
RESUMO
Background: In Japan, pollinosis caused by the Japanese cypress (JCy) Chamaecyparis obtusa is among the very common seasonal allergies. In JCy pollinosis, Cha o 1 is the first major allergen, and Cha o 2 is the second major allergen. Recently, Cha o 3 was identified as a new JCy pollen allergen in JCy pollinosis. However, the relative contribution of Cha o 3 to JCy pollinosis compared with that of Cha o 1 and that of Cha o 2 has not been fully elucidated. Objective: This study aimed to clarify the allergenicity of Cha o 3 compared with that of Cha o 1 and Cha o 2 in JCy pollinosis. Methods: We recruited 27 patients with JCy pollinosis and performed the basophil activation test (BAT) with native (n) Cha o 1, Cha o 2, and Cha o 3 purified from JCy pollen. In addition, we a performed JCy-specific IgE suppression test. Results: In the BAT, 26 of 27 patients (96%) and 18 of 27 patients (67%) showed positive basophil activation in response to n Cha o 1 and n Cha o 2, respectively, as judged by CD203c expression. Little CD203c expression in response to n Cha o 3 was seen. The presence of n Cha o 3 marginally reduced the titer levels of JCy-specific IgE. Conclusion: Cha o 3 showed little ability to activate basophils and suppress JCy-specific IgE titers compared with Cha o 1 or Cha o 2 in patients with JCy pollinosis. Thus, Cha o 3 may not be a major allergen in JCy pollinosis.
RESUMO
Context: Moon-like facies (MLF) are a typical side effect of glucocorticoid (GC) therapy; however, its predisposing factors, relationship with GC-induced complications, and effects on body image are not well understood. Objective: This study aimed to determine the predisposing factors for MLF during GC therapy; its association with GC-induced diabetes, hypertension, and dyslipidemia; and its effects on body image. Methods: This prospective observational study spanned 24 weeks and targeted patients who received GC therapy at the University of Yamanashi Hospital from June 2020 to August 2022. The MLF was defined based on the following 3 factors: (1) an increase in facial measurement lengths, (2) subjective facial changes by patients' self-assessment using a visual analog scale; (3) objective and qualitative facial changes assessed by physicians. We examined the predisposing factors for MLF and the association of MLF with GC-induced diabetes, hypertension, dyslipidemia, and body image. Results: The cumulative incidence rate of MLF at 24 weeks was 37.6%. Predisposing factors for MLF were an initial oral prednisolone dosage of ≥ 30â mg/day [odds ratio (OR) 63.91, 95% confidence interval (CI) 5.82-701.81] and female (OR 6.66, 95% CI 1.35-32.79). MLF showed a significant association with the onset of GC-induced diabetes (OR 6.58, 95% CI 1.25-34.74). MLF was also an independent factor contributing to body image disturbance (ß = -18.94, P = .01). Conclusion: MLF contributes to body image disturbance and is associated with the development of GC-induced diabetes; therefore, it is clinically important as a physical manifestation of GC therapy.
RESUMO
Introduction: Glomerulonephritis is frequent in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and crucial to disease outcomes. We conducted a detailed assessment of renal pathology in Japanese patients with AAV, and developed a new score that would predict renal outcome. Methods: Two hundred twenty-one patients who were diagnosed with AAV and underwent a kidney biopsy were enrolled. Data on glomerular, tubular, interstitial, and vascular lesions from kidney biopsies were analyzed; the 3 established classification and prognostic scoring systems (Berden Classification, Mayo Clinic/RPS Chronicity Score [MCCS], and ANCA Renal Risk Score [ARRS]) were validated. Further, we developed a new prognostic score by including variables relevant for Japanese patients with ANCA-glomerulonephritis. Results: Median follow-up was 60 months (interquartile range: 6-60). End-stage kidney disease (ESKD) risk prediction by the MCCS and the ARRS was confirmed. Moreover, our analysis identified 4 items with significant ESKD risk prediction capacity, namely percentage of cellular, fibrocellular, and fibrous crescents; and sclerotic glomeruli. Based on our findings, we created a score evaluating the percentage of these lesions to total glomeruli, the Percentage of ANCA Crescentic Score (PACS). The area under the receiver operating characteristic (ROC) curve evaluating PACS was 0.783. The PACS had a comparable performance as the ARRS in predicting ESKD. The optimal PACS cut-off for ESKD risk over 60 months was 43%. In addition, the percentage of cellular crescents and presence of interstitial inflammation were independent predictors of kidney function recovery. Conclusion: We developed a new score predicting renal prognosis using histopathological data of Japanese patients with ANCA-glomerulonephritis. Studies are needed to validate our results in international cohorts.
RESUMO
Precise control of the surface topographies of polymer materials is key to developing high-performance materials and devices for a wide variety of applications, such as optical displays, micro/nanofabrication, photonic devices, and microscale actuators. In particular, photocontrolled polymer surfaces, such as photoinduced surface relief, have been extensively studied mainly through photochemical mass transport. In this study, we propose a novel method triggering the mass transport by photopolymerization of liquid crystals with structured light and demonstrate the direct formation of microscale well and canal structures on the surface of polymer films. The wells and canals with depths of several micrometers and high aspect ratios, which are 10 times larger than those of previously reported structures, were found to be aligned in the center of non-irradiated areas. Furthermore, such well and canal structures can be arranged in two dimensions by designing light patterns. Real-time observations of canal structure formation reveal that anisotropic molecular diffusion during photopolymerization leads to a directed molecular alignment and subsequent surface structure formation. We believe that our proposed approach to designing microscale surface topographies has promising applications in advanced optical and mechanical devices.
RESUMO
A wide range of diseases, including cancer, autoimmune diseases, or neurodegenerative diseases, have been associated with single nucleotide mutations in their causative genes. Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9) system is a flexible and efficient genome engineering technology widely used for researches and therapeutic applications which offers immense opportunity to treat genetic diseases. The complex of Cas9 and the guide RNA acts as an RNA-guided endonuclease. Cas9 recognizes a sequence motif known as a protospacer adjacent motif (PAM), and then the guide RNA base pairs with its proximal target region of 20 nucleotides with sequence complementarity. Here we describe the procedure named single nucleotide polymorphism-distinguishable (SNPD)-CRISPR system which can suppress or enhance the expression of disease-causative gene with single nucleotide mutation distinguished from its wild-type. In this study, we used HRAS, one of most famous cancer-causative genes, as an example of a target gene.
Assuntos
Sistemas CRISPR-Cas , Polimorfismo de Nucleotídeo Único , Sistemas CRISPR-Cas/genética , RNA/genética , Nucleotídeos , Expressão GênicaRESUMO
In RNA interference (RNAi), small interfering RNA (siRNA) suppresses the expression of its target mRNA with a perfect complementary sequence. In addition, siRNA also suppresses the expression of unintended mRNAs with partially complementary sequences mainly within the siRNA seed region (nucleotides 2-8). This mechanism is highly similar to microRNA (miRNA)-mediated RNA silencing, and known as the siRNA-mediated off-target effect. Previously, we revealed that the off-target effect is induced through stable base-pairing between the siRNA seed region and off-target mRNAs, but not induced through unstable base-pairing. However, in our recent study, we found that the siRNA seed region consists of two functionally different domains: nucleotides 2-5, essential for off-target effects, and nucleotides 6-8, involved in both RNAi and off-target effects. In this study, we investigated the most responsible region for the off-target effect by conducting a comprehensive analysis of the thermodynamic properties of all possible siRNA subregions that involved a machine learning technique using a random sampling procedure. As a result, the thermodynamic stability of nucleotides 2-5 showed the highest positive correlation with the off-target effect, and nucleotides 8-14 showed the most negative correlation. Thus, it is revealed that the siRNA off-target effect is determined by the base-pairing stabilities of two different subregions with opposite effects.
Assuntos
Nucleotídeos , RNA de Cadeia Dupla , Pareamento de Bases/genética , Nucleotídeos/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismoRESUMO
In RNA interference (RNAi), small interfering RNA (siRNA) functions to suppress the expression of its target mRNA with perfect sequence complementarity. In a mechanism different from above, siRNA also suppresses unintended mRNAs with partial sequence complementarities, mainly to the siRNA seed region (nucleotides 2-8). This mechanism is largely utilized by microRNAs (miRNAs) and results in siRNA-mediated off-target effects. Thus, the siRNA seed region is considered to be involved in both RNAi and off-target effects. In this study, we revealed that the impact of 2'-O-methyl (2'-OMe) modification is different according to the nucleotide positions. The 2'-OMe modifications of nucleotides 2-5 inhibited off-target effects without affecting on-target RNAi activities. In contrast, 2'-OMe modifications of nucleotides 6-8 increased both RNAi and off-target activities. The computational simulation revealed that the structural change induced by 2'-OMe modifications interrupts base pairing between siRNA and target/off-target mRNAs at nucleotides 2-5 but enhances at nucleotides 6-8. Thus, our results suggest that siRNA seed region consists of two functionally different domains in response to 2'-OMe modifications: nucleotides 2-5 are essential for avoiding off-target effects, and nucleotides 6-8 are involved in the enhancement of both RNAi and off-target activities.
RESUMO
Hydroxychloroquine (HCQ), an antimalarial drug, is recommended for all patients with systemic lupus erythematosus (SLE), and is widely used around the world. HCQ has various beneficial effects, including antidiabetic effects but was unavailable in Japan until gaining approval for SLE treatment in 2015. We present herein the cases of two Japanese women with SLE and diabetes mellitus (DM) who were treated using HCQ and achieved reductions in glycosylated hemoglobin (HbA1c). A 48 year-old Japanese woman with SLE and DM (patient 1) received oral HCQ at 200 mg/day for the treatment of lupus nephritis. HbA1c levels decreased from 7.2-6.2% after 14 months of HCQ without any loss of body weight or alterations in doses of glucocorticoid or hypoglycemic agents. A 64 year-old Japanese woman with SLE and DM (patient 2) received oral HCQ at 200 mg and 400 mg on alternate days for the treatment of erythema. She also received intensive insulin therapy. HCQ drastically reduced both HbA1c levels, from 10.3 to 7.5%, and the insulin doses required without altering the doses of glucocorticoid or hypoglycemic agents, although body weight increased slightly. No episodes of hypoglycemia were seen in either patient. HCQ can achieve antidiabetic effects in Japanese SLE patients.
RESUMO
Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second-most common cause of death within the next 10 years. Due to the limited efficacy of available therapies, the survival rate of PDAC patients is very low. Oncogenic BRAF mutations are one of the major causes of PDAC, specifically the missense V600E and L485-P490 15-bp deletion mutations. Drugs targeting the V600E mutation have already been approved by the United States Food and Drug Administration. However, a drug targeting the deletion mutation at L485-P490 of the BRAF gene has not been developed to date. The BxPC-3 cell line is a PDAC-derived cell line harboring wild-type KRAS and L485-P490 deleted BRAF genes. These cells are heterozygous for BRAF, harboring both wild-type BRAF and BRAF with the 15-bp deletion. In this study, siRNA was designed for the targeted knockdown of 15-bp deletion-type BRAF mRNA. This siRNA repressed the phosphorylation of extracellular-signal-regulated kinase proteins downstream of BRAF and suppressed cell growth in vitro and in vivo. Furthermore, siRNAs with 2'-O-methyl modifications at positions 2-5 reduce the seed-dependent off-target effects, as confirmed by reporter and microarray analyses. Thus, such siRNA is a promising candidate therapy for 15-bp deletion-type BRAF-induced tumorigenesis.
RESUMO
BACKGROUND: During the COVID-19 pandemic, pedicle flaps instead of free flap transfer were recommended for head and neck reconstruction to reduce infection risk. Boron neutron-capture therapy in Japan was clinically approved in 2020 as a salvage radiotherapy for recurrent head and neck cancer following chemoradiotherapy. The efficacy and safety of salvage surgery following boron neutron-capture therapy remain unclear. CASE REPORT: We describe a 57-year-old male with crT4aN0M0 oral cancer after three different forms of radiotherapy including boron neutron-capture therapy, treated by salvage partial maxillectomy with both buccal fat pad and nasoseptal flaps. His postsurgical course was successful, without tracheostomy, and he had no Clavien- Dindo grade 3 or 4 complications. The pathological diagnosis was T4a squamous cell carcinoma with a negative surgical margin. No recurrence or metastasis had occurred at 113 days postoperatively. No opioid consumption was needed postoperatively. CONCLUSION: Pathological negative margins were achieved in this case and there were no severe complications. Further accrual of cases salvage surgery following boron neutron-capture therapy is required to clarify treatment strategies for recurrent head and neck cancer.