Activation of AMP-activated protein kinase stimulates the nuclear localization of glyceraldehyde 3-phosphate dehydrogenase in human diploid fibroblasts

In addition to its well-known glycolytic activity, GAPDH displays multiple functions, such as nuclear RNA export, DNA replication and repair, and apoptotic cell death. This functional diversity depends on its intracellular localization. In this study, we explored the signal transduction pathways involved in the nuclear translocation of GAPDH using confocal laser scanning microscopy of immunostained human diploid fibroblasts (HDFs). GAPDH was present mainly in the cytoplasm when cultured with 10% FBS. Serum depletion by culturing cells in a serum-free medium (SFM) led to a gradual accumulation of GAPDH in the nucleus, and this nuclear accumulation was reversed by the re-addition of serum or growth factors, such as PDGF and lysophosphatidic acid. The nuclear export induced by the re-addition of serum or growth factors was prevented by LY 294002 and SH-5, inhibitors of phosphoinositide 3-kinase (PI3K) and Akt/protein kinase B, respectively, suggesting an involvement of the PI3K signaling pathway in the nuclear export of GAPDH. In addition, 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR), an activator of AMP-activated protein kinase (AMPK), stimulated the nuclear translocation of GAPDH and prevented serum- and growth factor-induced GAPDH export. AMPK inhibition by compound C or AMPK depletion by siRNA treatment partially prevented SFM- and AICAR-induced nuclear translocation of GAPDH. Our data suggest that the nuclear translocation of GAPDH might be regulated by the PI3K signaling pathway acting mainly as a nuclear export signal and the AMPK signaling pathway acting as a nuclear import signal.Peairs A, 2009, CLIN EXP IMMUNOL, V156, P542, DOI 10.1111/j.1365-2249.2009.03924.xChen Z, 2009, CIRC RES, V104, P496, DOI 10.1161/CIRCRESAHA.108.187567Cao C, 2008, J BIOL CHEM, V283, P28897, DOI 10.1074/jbc.M804144200Li XX, 2008, ARTERIOSCL THROM VAS, V28, P1789, DOI 10.1161/ATVBAHA.108.172452Lombardi M, 2008, J CELL BIOL, V182, P327Sen N, 2008, NAT CELL BIOL, V10, P866, DOI 10.1038/ncb1747Kim HS, 2008, J BIOL CHEM, V283, P3731, DOI 10.1074/jbc.M704432200Du ZX, 2007, ENDOCRINOLOGY, V148, P4352, DOI 10.1210/en.2006-1511Harada N, 2007, J BIOL CHEM, V282, P22651, DOI 10.1074/jbc.M610724200Goirand F, 2007, J PHYSIOL-LONDON, V581, P1163, DOI 10.1113/jphysiol.2007.132589Barbini L, 2007, MOL CELL BIOCHEM, V300, P19, DOI 10.1007/s11010-006-9341-1Hurley RL, 2006, J BIOL CHEM, V281, P36662, DOI 10.1074/jbc.M606676200Hara MR, 2006, CELL MOL NEUROBIOL, V26, P527, DOI 10.1007/s10571-006-9011-6Tisdale EJ, 2006, J BIOL CHEM, V281, P8436, DOI 10.1074/jbc.M513031200Rattan R, 2005, J BIOL CHEM, V280, P39582, DOI 10.1074/jbc.M507443200Hara MR, 2005, NAT CELL BIOL, V7, P665, DOI 10.1038/ncb1268Sirover MA, 2005, J CELL BIOCHEM, V95, P45, DOI 10.1002/jcb.20399Jones RG, 2005, MOL CELL, V18, P283, DOI 10.1016/j.molcel.2005.03.027Tisdale EJ, 2004, J BIOL CHEM, V279, P54046, DOI 10.1074/jbc.M409472200Hardie DG, 2004, J CELL SCI, V117, P5479, DOI 10.1242/jcs.01540Li J, 2004, AM J PHYSIOL-ENDOC M, V287, pE834, DOI 10.1152/ajpendo.00234.2004Cooray S, 2004, J GEN VIROL, V85, P1065, DOI 10.1099/vir.0.1977-0Brown VM, 2004, J BIOL CHEM, V279, P5984, DOI 10.1074/jbc.M307071200Tisdale EJ, 2003, J BIOL CHEM, V278, P52524, DOI 10.1074/jbc.M309343200HAWLEY SA, 2003, J BIOL, V2, P28Schmitz HD, 2003, CELL BIOL INT, V27, P511, DOI 10.1011/S1065-6995(03)00096-9Tisdale EJ, 2002, J BIOL CHEM, V277, P3334, DOI 10.1074/jbc.M109744200Schmitz HD, 2001, EUR J CELL BIOL, V80, P419Dastoor Z, 2001, J CELL SCI, V114, P1643Yeo EJ, 2000, MOL CELLS, V10, P415Stein SC, 2000, BIOCHEM J, V345, P437Sirover MA, 1999, BBA-PROTEIN STRUCT M, V1432, P159Shashidharan P, 1999, NEUROREPORT, V10, P1149Rameh LE, 1999, J BIOL CHEM, V274, P8347Sawa A, 1997, P NATL ACAD SCI USA, V94, P11669Vincent MF, 1996, BIOCHEM PHARMACOL, V52, P999Reiss N, 1996, BIOCHEM MOL BIOL INT, V38, P711CORTON JM, 1995, EUR J BIOCHEM, V229, P558KAWAMOTO RM, 1986, BIOCHEMISTRY-US, V25, P657BOYCE ST, 1983, J INVEST DERMATOL S, V81, P33

Cosuppression of NF-κB and AICDA Overcomes Acquired EGFR-TKI Resistance in Non-Small Cell Lung Cancer

Background: Acquired resistance after EGFR-tyrosine kinase inhibitor (TKI) treatment is the rule rather than the exception. Overcoming resistance to EGFR-TKIs is essential if we are to develop better therapeutic strategies for lung cancer patients. Here, we examine the effector signaling pathways underlying TKI resistance and propose targets to overcome the resistance of lung adenocarcinoma (LAC) to TKI. Methods: We compared the expression of NF-κB, AICDA, Akt, IL-6, Jak2, and Stat3 by EGFR-TKI-resistant and EGFR-TKI-sensitive LAC cell lines, and by LAC patients treated with EGFR-TKIs; we then evaluated links between expression and treatment responses. We also examined the therapeutic effects of NF-κB and AICDA inhibition in EGFR-TKI-resistant LACs. Results: NF-κB and AICDA were more expressed by EGFR-TKI-resistant LACs than by EGFR-TKI-sensitive LACs. EGFR-TKIs induced a dose-dependent increase in the expression of NF-κB, AICDA, and IL-6. Inhibition of NF-κB suppressed the expression of AICDA, Akt, and IL-6 in EGFR-TKI-resistant and EGFR-TKI-sensitive LACs, whereas knockdown of AICDA suppressed the expression of NF-κB and Akt in both cell types. Treating EGFR-TKI-resistant LACs with an EGFR-TKI, alongside cosuppression of NF-κB and AICDA, had a significant therapeutic effect. Conclusion: Treatment with an EGFR-TKI plus cosuppression of NF-κB and AICDA may be a promising strategy to overcome EGFR-TKI resistance in LACs

Multi-scale Hybrid Vision Transformer for Learning Gastric Cancer Histology

Gastric endoscopic screening is an effective way to decide appropriate gastric cancer (GC) treatment at an early stage, reducing GC-associated mortality rate. Although artificial intelligence (AI) has brought a great promise to assist pathologist to screen digitalized whole slide images, existing AI systems are limited in fine-grained cancer subclassifications and have little usability in planning cancer treatment. We propose a practical AI system that enables five subclassifications of GC pathology, which can be directly matched to general GC treatment guidance. The AI system is designed to efficiently differentiate multi-classes of GC through multi-scale self-attention mechanism using 2-stage hybrid Vision Transformer (ViT) networks, by mimicking the way how human pathologists understand histology. The AI system demonstrates reliable diagnostic performance by achieving class-average sensitivity of above 0.85 on a total of 1,212 slides from multicentric cohort. Furthermore, AI-assisted pathologists show significantly improved diagnostic sensitivity by 12% in addition to 18% reduced screening time compared to human pathologists. Our results demonstrate that AI-assisted gastric endoscopic screening has a great potential for providing presumptive pathologic opinion and appropriate cancer treatment of gastric cancer in practical clinical settings

Targeting the Sequences of Circulating Tumor DNA of Cholangiocarcinomas and Its Applications and Limitations in Clinical Practice

Cholangiocarcinoma is a malignant epithelial tumor arising from bile ducts that is frequently fatal. Diagnosis is difficult due to tumor location in the biliary tract. Earlier diagnosis requires less invasive methods of identifying effective biomarkers for cholangiocarcinoma. The present study investigated the genomic profiles of cell-free DNA (cfDNA) and DNA from corresponding primary cholangiocarcinomas using a targeted sequencing panel. Somatic mutations in primary tumor DNA and circulating tumor DNA (ctDNA) were compared and clinical applications of ctDNA validated in patients with cholangiocarcinoma. A comparison of primary tumor DNA and ctDNA identified somatic mutations in patients with early cholangiocarcinomas that showed clinical feasibility for early screening. The predictive value of single-nucleotide variants (SNVs) of preoperative plasma cfDNA positive for somatic mutations of the primary tumor was 42%. The sensitivity and specificity of postoperative plasma SNVs in detecting clinical recurrence were 44% and 45%, respectively. Targetable fibroblast growth factor receptor 2 (FGFR2) and Kirsten rat sarcoma virus (KRAS) mutations were detected in 5% of ctDNA samples from patients with cholangiocarcinoma. These findings showed that genomic profiling of cfDNA was useful in clinical evaluation, although ctDNA had limited ability to detect mutations in cholangiocarcinoma patients. Serial monitoring of ctDNA is important clinically and in assessing real-time molecular aberrations in cholangiocarcinoma patients

Patterns of Extrathoracic Metastasis in Lung Cancer Patients

Metastasis is a major cause of death in lung cancer patients. Therefore, a deeper understanding of the metastatic mechanisms is important for developing better management strategies for lung cancer patients. This study evaluated the patterns of extrathoracic metastases in lung cancer. We retrieved data for 25,103 lung cancer patients from an institutional database and then evaluated the impacts of clinicopathologic factors on metastasis patterns. We found that 36.5% of patients had extrathoracic metastasis. Younger patients had a significantly higher extrathoracic metastasis rate in most histologic subtypes. Metastases to the bone (58.3%), central nervous system (CNS) (44.3%), liver (26.6%) and adrenal gland (18.3%) accounted for 85.5% of all extrathoracic metastases. Patients with nonmucinous adenocarcinoma had significantly higher bone metastasis rate. Patients with small cell carcinoma and large cell neuroendocrine carcinoma (LCNEC) had significantly higher liver metastasis rates. Further, patients with LCNEC also had a significantly lower bone metastasis rate, and patients with squamous cell carcinoma had a significantly lower CNS metastasis rate. Patients with multiple cancers had similar patterns of metastasis compared to patients with only lung cancer. In conclusion, different histologic subtypes of lung cancer have different metastatic patterns. Our study might help clinicians decide on follow-up strategies

Conditions for laryngeal mask airway placement in terms of oropharyngeal leak pressure: a comparison between blind insertion and laryngoscope-guided insertion

Abstract Background Insertion under laryngoscopic guidance has been used to achieve ideal positioning of the laryngeal mask airway (LMA). However, to date, the efficacy of this technique has been evaluated only using fiberoptic evaluation, and the results have been conflicting. Other reliable tests to evaluate the efficacy of this technique have not been established. Recently, it has been suggested that the accuracy of LMA placement can be determined by clinical signs such as oropharyngeal leak pressure (OPLP). The aim of this study was to assess the efficacy of LMA insertion under laryngoscopic guidance using OPLP as an indicator. Methods After approved by the institutional ethics committee, a prospective comparison of 100 patients divided into 2 groups (50 with blind technique and 50 with the laryngoscope technique) were evaluated. An LMA (LarySeal™, Flexicare medical Ltd., UK) was inserted using the blind approach in the blind insertion group and using laryngoscopy in the laryngoscope-guided insertion group. The OPLP, fiberoptic position score, whether the first attempt at LMA insertion was successful, time taken for insertion, ease of LMA insertion, and adverse airway events were recorded. Results Data were presented as mean ± standard deviation. The OPLP was higher in the laryngoscope-guided insertion group than in the blind insertion group (21.4 ± 8.6 cmH2O vs. 18.1 ± 6.1 cmH2O, p = 0.031). The fiberoptic position score, rate of success in the first attempt, ease of insertion, and pharyngolaryngeal adverse events were similar between both groups. The time taken for insertion of the LMA was significantly longer in the laryngoscope-guided insertion group, compared to blind insertion group (35.9 ± 9.5 s vs. 28.7 ± 9.5 s, p < 0.0001). Conclusion Laryngoscope-guided insertion of LMA improves the airway seal pressure compared to blind insertion. Our result suggests that it may be a useful technique for LMA insertion. Trial registration cris.nih.go.kr, identifier: KCT0001945 (2016-06-17)

PAR2 Deficiency Induces Mitochondrial ROS Generation and Dysfunctions, Leading to the Inhibition of Adipocyte Differentiation

Protease-activated receptor 2 (PAR2) is a member of G-protein-coupled receptors and affects ligand-modulated calcium signaling. Although PAR2 signaling promotes obesity and adipose tissue inflammation in high fat- (HF-) fed conditions, its role in adipocyte differentiation under nonobesogenic conditions needs to be elucidated. Here, we used several tissues and primary-cultured adipocytes of mice lacking PAR2 to study its role in the development of adipose tissues. C57BL/6J mice with PAR2 deficiency exhibited a mild lipodystrophy-like phenotype in a chow diet-fed condition. When adipocyte differentiation was examined using primary-cultured preadipocytes, PAR2 deficiency led to a notable decrease in adipocyte differentiation and related protein expression, and PAR2 agonist treatment elevated adipocyte differentiation. Regarding the mechanism, PAR2-deficient preadipocytes exhibited impaired mitochondrial energy consumption. Further studies indicated that calcium-related signaling pathways for mitochondrial biogenesis are disrupted in the adipose tissues of PAR2-deficient mice and PAR2-deficient preadipocytes. Also, a PAR2 antagonist elevated mitochondrial reactive oxygen species and reduced the MitoTracker fluorescent signal in preadipocytes. Our studies revealed that PAR2 is important for the development of adipose tissue under basal conditions through the regulation of mitochondrial biogenesis and adipocyte differentiation

Characterization of Poorly Cohesive and Signet Ring Cell Carcinomas and Identification of PTPRM as a Diagnostic Marker

Background and aims. Signet ring cell (SRC) and poorly cohesive (PC) gastric carcinomas are morphologically similar but exhibit different biological behavior. We compared the clinical and molecular characteristics of SRC and PC carcinomas. Methods. Diffuse-type gastric cancer (GC) cases were classified into SRC carcinomas (>90% of SRCs), PC carcinomas (<10% of SRCs), and combined PC/SRC carcinomas (≤90% but ≥10% of SRCs). The gene expression patterns in SRC and PC carcinomas were examined by transcriptome and protein immunohistochemistry analyses, and diagnostic and prognostic biomarkers were identified. Results. SRC and PC carcinomas showed significantly different clinical behaviors but shared common RNA expression patterns. PC carcinomas showed an increased expression of genes related to cancer progression. Among genes differentially expressed between PC and SRC carcinomas, protein tyrosine phosphatase receptor type M (PTPRM) was overexpressed in PC and related to unfavorable clinical factors. Conclusion. We found that PC and SRC carcinomas had distinct clinical characteristics and should be classified as different carcinoma types. PTPRM was identified as a potential diagnostic and prognostic biomarker for PC carcinomas and could represent a potential therapeutic target