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BACKGROUND: This study aimed to investigate the laparoscopic gastrectomy (LG) performance of non-Endoscopic Surgical Skill Qualification System (ESSQS)-qualified surgeons under the ESSQS-qualified surgeon guidance and compare oncological outcomes of gastric cancer to LG performed by the ESSQS-qualified surgeons. METHODS: This study enrolled 1,030 patients diagnosed with both clinical and pathological stage ≤ III gastric cancer and undergoing LG from January 2009 to June 2019. ESSQS-qualified surgeons served as the operator or the instructive assistant in all LG procedures involving them. A propensity score-matched analysis was used to retrospectively compare the long-term outcomes between the ESSQS-qualified and non-ESSQS-qualified surgeons. RESULTS: Each group included 315 pairs after propensity score matching. The 3-year recurrence-free survival rates were 84.4% and 81.7% in the non-ESSQS and ESSQS groups, respectively. The difference was 2.7% (95% confidence interval: - 3.20%-8.44%, P < 0.001), and the non-ESSQS group statistically demonstrated noninferiority as the lower 95% confidence limit was greater than the prespecified margin of -10%, indicating the achieved primary endpoint. No significant differences in 5-year recurrence-free survival (non-ESSQS: 78.5% vs. ESSQS: 77.4%, P = 0.627) and 5-year overall survival (non-ESSQS: 80.9% vs. ESSQS: 79.3%, P = 0.475) were found between the two groups. The oncological outcomes stratified according to the presence of pathological stage I, II, and III disease did not significantly differ between the two groups. CONCLUSIONS: LG performed by non-ESSQS-qualified surgeons achieved comparable oncological outcomes to the ESSQS-qualified surgeons, as long as ESSQS-qualified surgeons provided intraoperative instructions, in a high-volume center.
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An exceptional expression of claudins (CLDNs), tight junction (TJ) proteins, is observed in various solid cancer tissues. However, the pathophysiological roles of CLDNs have not been clarified in detail. CLDN14 is highly expressed in human colorectal cancer (CRC) tissues and cultured cancer epithelial cells. We found CLDN14 silencing decreased cell viability without affecting spheroid size in the three-dimensional (3D) spheroid model of DLD-1 cells derived from human CRC. Mitochondria activity and oxidative stress level were reduced by CLDN14 silencing. Furthermore, CLDN14 silencing decreased the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its target antioxidative genes. CLDN14 was colocalized with ZO-1, a scaffolding protein in the TJ. CLDN14 silencing induced the disruption of TJ barrier such as the reduction of transepithelial electrical resistance and elevation of fluxes of small molecules including glucose in two-dimensional (2D) cultured model,. The depletion of glucose induced the elevation of ROS generation, mitochondria activity, and Nrf2 expression. These results suggest that CLDN14 increases Nrf2 expression in spheroids mediated via the formation of paracellular barrier to glucose. The cytotoxicities of doxorubicin, an anthracycline anticancer drug, and oxaliplatin, a platinum-based agent, were augmented by an Nrf2 activator in 2D cultured cells. The anticancer drug-induced toxicity was enhanced by CLDN14 silencing in 3D spheroids. We suggest that CLDN14 may potentiate chemoresistance mediated by the suppression of paracellular glucose permeability and activation of the Nrf2 signaling pathway in CRC cells.
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Claudinas , Neoplasias Colorrectales , Regulación hacia Abajo , Resistencia a Antineoplásicos , Silenciador del Gen , Factor 2 Relacionado con NF-E2 , Humanos , Antineoplásicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Claudinas/metabolismo , Claudinas/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/efectos de los fármacos , Uniones Estrechas/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , Proteína de la Zonula Occludens-1/genéticaRESUMEN
PURPOSE: The purpose of this study is to compare the shear bond strength of ultraviolet (UV)-polymerized resin to 3D-printed denture materials, both with and without post-polymerization. Moreover, the effects of surface treatment and thermocycling on shear bond strength after post-polymerization were investigated. METHODS: Cylindrical 3D-printed denture bases and teeth specimens were prepared. The specimens are subjected to two tests. For Test 1, the specimens were bonded without any surface treatment or thermal stress for comparison with and without post-polymerization. In Test 2, specimens underwent five surface treatments: untreated (CON), ethyl acetate (EA), airborne particle abrasion (APA) with 50 µm (50-APA) and 110 µm alumina (110-APA), and tribochemical silica coating (TSC). A UV-polymerized resin was used for bonding. Half of the Test 2 specimens were thermocycled for 10,000 cycles. Shear bond strength was measured and analyzed using Kruskal-Wallis and Steel-Dwass tests (n = 8). RESULTS: In Test 1, post-polymerization significantly reduced shear bond strength of both 3D-printed denture materials (P < 0.05). No notable difference was observed between the denture teeth and the bases (P > 0.05). In Test 2, before thermocycling, the CON and EA groups exhibited low bond strengths, while the 50-APA, 110-APA, and TSC groups exhibited higher bond strengths. Thermocycling did not reduce bond strength in the latter groups, but significantly reduced bond strength in the EA group (P < 0.001). CONCLUSIONS: Post-polymerization can significantly reduce the shear bond strength of 3D-printed denture materials. Surface treatments, particularly APA and TSC, maintained bond strength even after thermocycling.
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Undergoing another surgery after a previous abdominal procedure can sometimes result in significant abdominal adhesions. We present a case of robot-assisted low anterior resection in a patient with rectal cancer who had a urinary reservoir. A 65-year-old male patient underwent robot-assisted total bladder resection and creation of a urinary reservoir for bladder cancer in 2013. He presented with melena. Thus, the findings revealed advanced low rectal cancer. The robot-assisted low anterior resection was performed in 2022. Extensive adhesions were observed in the pelvic space. The indocyanine green function was appropriately used, and the robotic surgery was completed without injury to the urinary reservoir or major complications. The surgical time was 510 min, and the blood loss volume was 15 mL. The patient had been recurrence free for 12 months following the surgery. Robot-assisted surgery can be beneficial for patients with rectal cancer with significant pelvic adhesions.
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Laparoscopía , Proctectomía , Neoplasias del Recto , Procedimientos Quirúrgicos Robotizados , Robótica , Masculino , Humanos , Anciano , Resultado del Tratamiento , Laparoscopía/métodos , Neoplasias del Recto/complicaciones , Neoplasias del Recto/cirugía , Proctectomía/métodos , Procedimientos Quirúrgicos Robotizados/métodosRESUMEN
Accumulation of lipotoxic lipids, such as free cholesterol, induces hepatocyte death and subsequent inflammation and fibrosis in the pathogenesis of nonalcoholic steatohepatitis (NASH). However, the underlying mechanisms remain unclear. We have previously reported that hepatocyte death locally induces phenotypic changes in the macrophages surrounding the corpse and remnant lipids, thereby promoting liver fibrosis in a murine model of NASH. Here, we demonstrated that lysosomal cholesterol overload triggers lysosomal dysfunction and profibrotic activation of macrophages during the development of NASH. ß-cyclodextrin polyrotaxane (ßCD-PRX), a unique supramolecule, is designed to elicit free cholesterol from lysosomes. Treatment with ßCD-PRX ameliorated cholesterol accumulation and profibrotic activation of macrophages surrounding dead hepatocytes with cholesterol crystals, thereby suppressing liver fibrosis in a NASH model, without affecting the hepatic cholesterol levels. In vitro experiments revealed that cholesterol-induced lysosomal stress triggered profibrotic activation in macrophages predisposed to the steatotic microenvironment. This study provides evidence that dysregulated cholesterol metabolism in macrophages would be a novel mechanism of NASH.
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Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Modelos Animales de Enfermedad , Cirrosis Hepática , Macrófagos , Colesterol , LisosomasRESUMEN
BACKGROUND: The presence of functional tricuspid regurgitation (TR) is associated with mortality and morbidity. Although uniform management with a tricuspid annuloplasty ring is currently considered as a standard surgical procedure, high rates of residual TR despite annuloplasty are reported. Therefore, the identification of the TR mechanisms would be necessary to provide personalized treatment for each TR patient. METHODS: This study population consisted of 106 patients with mitral regurgitation (MR) who were scheduled for procedure. Transthoracic and transesophageal echocardiography were performed prior to mitral valve intervention. We performed three-dimensional quantitative assessment including tricuspid annular (TA) area and the distance between the three commissures of tricuspid valve. RESULTS: Significant TR, which is defined as moderate or greater TR, was detected in 23 (22%). TA area (P < 0.01), the distance of septal-leaflet length (SL) (P = 0.03) and posterior-leaflet length (PL) (p = 0.02) were significantly associated with significant TR, while TA diameter assessed by transthoracic echocardiography was not. When patients were divided into four groups according to SL and PL, the group with longer SL and PL had a significantly higher incidence of significant TR (P < 0.01). CONCLUSIONS: Greater stretch of the septal and posterior leaflet between commissures and larger TA area are associated with significant TR in patients with severe MR. In order to prevent TR recurrence, the intervention of the septal leaflet in tricuspid annuloplasty may be beneficial. The precise implement of three-dimensional transesophageal echocardiography of tricuspid valve is valuable for a personalized strategy of tricuspid annuloplasty.
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Ecocardiografía Tridimensional , Insuficiencia de la Válvula Tricúspide , Humanos , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/cirugía , Insuficiencia de la Válvula Tricúspide/etiología , Ecocardiografía Transesofágica/métodos , Valor Predictivo de las Pruebas , Válvula Tricúspide/diagnóstico por imagen , Válvula Tricúspide/cirugía , Ecocardiografía/métodosRESUMEN
Plants defend against folivores by responding to folivore-derived elicitors following activation of signaling cascade networks. In Arabidopsis, HAK1, a receptor-like kinase, responds to polysaccharide elicitors (Frα) that are present in oral secretions of Spodoptera litura larvae to upregulate defense genes (e.g., PDF1.2) mediated through downstream cytoplasmic kinase PBL27. Here, we explored whether other protein kinases, including CPKs and CRKs, function with PBL27 in the intracellular signaling network for anti-herbivore responses. We showed that CRK2 and CRK3 were found to interact with PBL27, but CPKs did not. Although transcripts of PDF1.2 were upregulated in leaves of wild-type Arabidopsis plants in response to mechanical damage with Frα, this failed in CRK2- and PBL27-deficient mutant plants, indicating that the CRK2/PBL27 system is predominantly responsible for the Frα-responsive transcription of PDF1.2 in S. litura-damaged plants. In addition to CRK2-phosphorylated ERF13, as shown previously, ethylene signaling in connection to CRK2-phosphorylated PBL27 was predicted to be responsible for transcriptional regulation of a gene for ethylene response factor 13 (ERF13). Taken together, these findings show that CRK2 regulates not only ERF13 phosphorylation but also PBL27-dependent de novo synthesis of ERF13, thus determining active defense traits against S. litura larvae via transcriptional regulation of PDF1.2.
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The patient is a 60-year-old female with a history of multiple times of recurrences of an esophageal diverticulum. She was referred for a diagnosis of persistent dysphagia and vomiting. Balloon dilation did not improve the symptoms; thus, she was referred for surgery. Esophageal fluoroscopy revealed a 5 cm diverticulum. There was no significant change in the size before and after dilation. Gastrointestinal endoscopy revealed a diverticulum in the lower esophagus, with a residue accumulation. The esophagus directly below the diverticulum was narrowed. The patient was diagnosed with recurrent lower esophageal diverticulum and underwent surgery. The operative findings showed poor coloration of the gastric fundus surrounding operated before by Nissen's method, so the patient underwent lower esophagogastric resection and interstitial jejunal reconstruction. The postoperative course was uneventful and discharged on the 19th day. She is 6 years postoperatively and gained six kg compared to her preoperative weight. She has remained in excellent health.
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The molecular pathogenesis of nonalcoholic steatohepatitis (NASH) includes a complex interaction of metabolic stress and inflammatory stimuli. Considering the therapeutic goals of NASH, it is important to determine whether the treatment can prevent the progression from NASH to hepatocellular carcinoma. Taxifolin, also known as dihydroquercetin, is a natural bioactive flavonoid with antioxidant and anti-inflammatory properties commonly found in various foods and health supplement products. In this study, we demonstrated that Taxifolin treatment markedly prevented the development of hepatic steatosis, chronic inflammation, and liver fibrosis in a murine model of NASH. Its mechanisms include a direct action on hepatocytes to inhibit lipid accumulation. Taxifolin also increased brown adipose tissue activity and suppressed body weight gain through at least two distinct pathways: direct action on brown adipocytes and indirect action via fibroblast growth factor 21 production in the liver. Notably, the Taxifolin treatment after NASH development could effectively prevent the development of liver tumors. Collectively, this study provides evidence that Taxifolin shows pleiotropic effects for the treatment of the NASH continuum. Our data also provide insight into the novel mechanisms of action of Taxifolin, which has been widely used as a health supplement with high safety.
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Enfermedad del Hígado Graso no Alcohólico , Humanos , Animales , Ratones , Enfermedad del Hígado Graso no Alcohólico/etiología , Hígado/metabolismo , Obesidad/metabolismo , Carcinogénesis/metabolismo , Transformación Celular Neoplásica/patología , Ratones Endogámicos C57BL , Modelos Animales de EnfermedadRESUMEN
Strongyloides is a genus of parasitic nematodes of vertebrates comprising approximately 50 documented species, each with various host ranges. Among these, three species (S. stercoralis, S. fuelleborni, and S. cebus) are known to infect primate hosts. S. fuelleborni typically infects non-human primates in the Old World. To complement the existing information on the global genetic structure of this species, we conducted a genotyping study of S. fuelleborni samples collected from rhesus macaques in Myanmar, Japanese macaques in Japan, and some zoo-kept primates. This study identified a novel haplotype group in isolates from the Myanmar rhesus macaques. Subsequently, we obtained the complete or nearly complete mitochondrial genome sequences of S. fuelleborni, S. cebus (Strongyloides of New World monkeys), and S. vituli (Strongyloides of cattle). Phylogenetic analysis based on concatenated mitochondrial protein sequences of various Strongyloides species indicated a close relationship between S. fuelleborni, S. vituli and S. papillosus (Strongyloides in sheep and cattle). S. cebus is quite distantly related to both S. fuelleborni and S. stercoralis, which led to the hypothesis that the three primate Strongyloides species evolved independently as parasites of primates.
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Genoma Mitocondrial , Bovinos , Ovinos , Animales , Filogenia , Strongyloides/genética , Macaca mulatta , Cebus , Macaca fuscata , Genética de PoblaciónRESUMEN
Claudin-2 (CLDN2), a component of tight junctions, is abnormally expressed in human lung adenocarcinoma tissue. CLDN2 contributes to chemoresistance in human lung adenocarcinoma-derived A549 cells, and it may be a target for cancer therapy. Here, we found that coffee ingredients, namely caffeine and theobromine, decreased the protein level of CLDN2 in human lung adenocarcinoma-derived A549 cells. In contrast, other components, such as theophylline and chlorogenic acid, had no effect. These results indicate that the 7-methyl group in methylxanthines may play a key role in the reduction in CLDN2 expression. The caffeine-induced reduction in the CLDN2 protein was inhibited by chloroquine, a lysosome inhibitor. In a protein-stability assay using cycloheximide, CLDN2 protein levels decreased faster in caffeine-treated cells than in vehicle-treated cells. These results suggest that caffeine accelerates the lysosomal degradation of CLDN2. The accumulation and cytotoxicity of doxorubicin were dose-dependently increased, which was exaggerated by caffeine but not by theophylline in spheroids. Caffeine decreased nuclear factor-erythroid 2-related factor 2 (Nrf2) levels without affecting hypoxia-inducible factor-1α levels. Furthermore, caffeine decreased the expression of Nrf2-targeted genes. The effects of caffeine on CLDN2 expression and anticancer-drug-induced toxicity were also observed in lung adenocarcinoma RERF-LC-MS cells. We suggest that caffeine enhances doxorubicin-induced toxicity in A549 spheroids mediated by the reduction in CLDN2 and Nrf2 expression.
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Adenocarcinoma del Pulmón , Antineoplásicos , Neoplasias Pulmonares , Humanos , Claudina-2 , Células A549 , Cafeína/farmacología , Cafeína/uso terapéutico , Factor 2 Relacionado con NF-E2/genética , Neoplasias Pulmonares/genética , Teofilina , Adenocarcinoma del Pulmón/metabolismo , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéuticoRESUMEN
Familial adenomatous polyposis (FAP) is an autosomal dominant disorder characterized by the presence of at least 100 adenomatous polyps in the colon and rectum. The risk of upper gastrointestinal tumors is relatively high in patients with FAP, but a case of triple cancers has not been reported in the literature. We herein report a case of metachronous triple cancers of the stomach, duodenum and rectum in a patient with FAP.
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Although the Cockcroft-Gault equation is still used for the dose adjustment of many drugs that have been approved prior to creatinine standardization, the clinical impact of standardized creatinine in the dose adjustment of capecitabine is poorly understood. We focused on patients with borderline renal function and evaluated the tolerability and safety of capecitabine in patients who received capecitabine plus oxaliplatin (Cape-Ox). We retrospectively identified patients with resected colorectal cancer who had received adjuvant therapy with Cape-Ox regimen. Creatinine clearance (CrCL) was calculated by the Cockcroft-Gault equation with standardized creatinine measured using enzymatic methods, and adjusted CrCL was estimated by adding 0.2 (mg/dL) to the serum creatinine in the equation. We defined patients with "pseudo-normal" renal function as those who had an adjusted CrCL of ≤50 mL/min in patients with normal renal function (CrCL >50 mL/min). We evaluated the tolerability and grade 2 or severer adverse events of capecitabine treatment. One hundred four patients had normal and 10 had impaired renal function (CrCL <50 mL/min). Among the 104 patients with normal renal function, 23 (22.1%) had pseudo-normal renal function. Seventeen patients completed the eight cycles of Cape-Ox therapy without treatment delay or dose reduction, and all of them had truly normal renal function. The patients with pseudo-normal renal function were more likely to have grade 2 or severer thrombocytopenia than those with truly normal renal function. We should recognize correctly the clinical impact of standardized creatinine in the treatment of borderline renal function with Cape-Ox regimen in patients.
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The patient is a 58-year-old woman. She was referred to our hospital following a computed tomography scan that revealed a 2-cm tumor-like lesion in the pancreatic body. Endoscopic ultrasound fine-needle aspiration examination revealed a suspected undifferentiated carcinoma with pleomorphic type. The patient was diagnosed with anaplastic carcinoma of the pancreas (ACP) and underwent distal pancreatectomy with lymph nodes dissection. The resected body and tail of the pancreas had a nodular tumor measuring 30 mm in diameter. Histologically, the main lesion of the tumor showed well-differentiated adenocarcinoma, and diffuse proliferation of atypical short spindle cells and round cells accompanied by multinucleated giant cells aggregation was observed around the tubular structure; hence, it was diagnosed with ACP. The postoperative course was uneventful, and the patient was discharged 14 days after the operation. It has already been about 5 years since the surgery, and although the tumor has recurred, the patient is still alive and undergoing chemotherapy.
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Cases of delayed colo-anal anastomosis (DCAA) are currently reported instead of the colo-anal anastomosis with a protective loop ileostomy for rectal cancer. Post-operative colonic ischemia is considered as one of the serious complications of colorectal resection. Although indication of DCAA should be carefully selected, we experienced a case of post-operative stenosis caused by colonic ischemia after low anterior resection for rectal cancer, followed by this procedure.
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BACKGROUND: Biologics are an important treatment option for patients with severe asthma. Four biologics are available in Japan, and an overlapping eligibility has been observed. The eligibility and availability of drugs depend on the local regulations of different countries. However, there is no precise information about the eligibility for biologics, including dupilumab, in Japan. The aim of the study was to investigate the overlapping eligibility and to analyze the phenotypes of patients with multiple eligibility. METHODS: In this observational study, a retrospective chart review of patients was performed. The eligibility criteria for omalizumab were IgE 30-1500IU/mL and positive IgE for perennial aeroallergen. The eligibility criteria for IL-5-targeted biologics (mepolizumab and benralizumab) were eosinophil counts (Eos) > 150µL, while those for dupilumab were Eos > 150µL or fraction of exhaled nitric oxide (FeNO) > 150ppb or IgE > 167IU/mL. Severe asthma was defined by the severity criteria under treatment based on Japanese guidelines for adult asthma. RESULTS: One hundred patients with severe asthma were identified. The eligibility for omalizumab, IL-5-targeted therapies, and dupilumab was 43%, 69%, and 82%, respectively. Thirty percent of the patients were eligible for all the four biologics and showed the lowest FEV1, frequent exacerbation history, and the highest levels of Eos, FeNO, and serum periostin. Only 11% of the patients were not indicated for any biologics. CONCLUSION: A considerable portion of patients was eligible for all the biologics. Asthma control was poor, and type 2 inflammation was prominent in such patients.
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Antiasmáticos , Asma , Productos Biológicos , Antiasmáticos/uso terapéutico , Asma/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Eosinófilos , Humanos , Inmunoglobulina E , Interleucina-5 , Omalizumab/uso terapéutico , Fenotipo , Estudios RetrospectivosRESUMEN
We report a successful case of robot-assisted surgery for Stage â £ gastric cancer with liver metastasis. A 70s man diagnosed with advanced gastric cancer with S3 solitary liver metastasis, and received a chemotherapy with S-1 and cisplatin. After 4 courses of chemotherapy, liver metastatic lesion was disappeared. Thus, robotic distal gastrectomy and partial liver resection were performed. Operating time was 391 minutes, and amount of intraoperative blood loss was 11 mL. The postoperative course was uneventful, and the patient was discharged 11 days after surgery. Histologic examination revealed no viable malignant cells in the resected liver, with a diagnosis of ypT2N1M0, ypStage â ¡A. The patient is alive with no recurrence 12 months after surgery, without adjuvant chemotherapy.
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Neoplasias Hepáticas , Procedimientos Quirúrgicos Robotizados , Neoplasias Gástricas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Cisplatino/uso terapéutico , Gastrectomía , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Masculino , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugíaRESUMEN
There are two major deadenylase complexes, Ccr4-Not and Pan2-Pan3, which shorten the 3' poly(A) tail of mRNA and are conserved from yeast to human. We have previously shown that the Ccr4-mediated deadenylation plays the important role in gene expression regulation in the yeast stationary phase cell. In order to further understand the role of deadenylases in different growth condition, in this study we investigated the effect of deletion of both deadenylases on the cell in non-fermentable carbon containing media. We found that both ccr4Δ and ccr4Δ pan2Δ mutants showed similar growth defect in YPD media: when switched to media containing non-fermentable source (Glycerol-Lactate) only the ccr4Δ grew while the ccr4Δ pan2Δ did not. Ccr4, Pan2, and Pan3 were phosphorylated in GlyLac medium, suggesting that the activities of Ccr4, Pan2, and Pan3 may be regulated by phosphorylation in response to change of carbon sources. To get insights how Ccr4 and Pan2 function in the cell growth in media containing non-fermentable source only, we isolated multicopy suppressors for the growth defect on YPGlyLac media of the ccr4Δ pan2Δ mutant and identified two genes, STM1 and REX2, which encode a ribosome-associated protein and a 3'-5' RNA exonuclease, respectively. Our results suggest that the Pan2-Pan3 complex, together with the Ccr4-Not complex, has important roles in the growth on non-fermentable carbon sources.
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Carbono/farmacología , Fermentación , Complejos Multiproteicos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomyces cerevisiae/metabolismo , Proliferación Celular/efectos de los fármacos , Medios de Cultivo , Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Gluconeogénesis/efectos de los fármacos , Gluconeogénesis/genética , Mitocondrias/efectos de los fármacos , Mitocondrias/genética , Mutación/genética , Fosforilación/efectos de los fármacos , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/efectos de los fármacosRESUMEN
Claudin-2 (CLDN2), a tight junctional protein, is involved in the chemoresistance in a three-dimensional spheroid culture model of human lung adenocarcinoma A549 cells. However, the mechanism has not been fully clarified. We found that the knockdown of CLDN2 expression by siRNA in the spheroid reduces the expression of glucose transporters and metabolic enzymes. In a two-dimensional culture model, the expression of these proteins was increased by glucose deprivation or fasentin, an inhibitor of glucose transporter. In addition, the expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant enzymes including heme oxygenase-1, NAD(P)H:quinone oxidoreductase-1, and a glutamate-cysteine ligase modifier subunit were increased by fasentin. The fluorescence intensities of JC-1, a probe of mitochondrial membrane potential, and MitoROS 580, a probe of mitochondrial superoxide production, were increased by fasentin. These results suggest that mitochondrial production of reactive oxygen species is increased by glucose deficiency. The knockdown of CLDN2 enhanced the flux of 2-deoxy-2-[(7-nitro-2,1,3-benzoxadiazol-4-yl)amino]-D-glucose (2-NBDG), a fluorescent deoxyglucose derivative, in a transwell assay, and the accumulation of glucose and 2-NBDG in spheroid cells. The expression of Nrf2 was decreased by CLDN2 knockdown, which was inhibited by fasentin and sulforaphane, a typical Nrf2 activator, in spheroid cells. The sensitivity of spheroid cells to doxorubicin, an anthracycline antitumor antibiotic, was enhanced by CLDN2 knockdown, which was inhibited by fasentin and sulforaphane. We suggest that CLDN2 induces chemoresistance in spheroid cells mediated through the inhibition of glucose transport and activation of the Nrf2 signal.