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1.
Medicina (Kaunas) ; 60(2)2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38399524

ABSTRACT

Background and Objectives: Lung cancer is a leading cause of cancer mortality in Taiwan. With rapid advancement of targeted therapeutics in non-small cell lung cancers, next-generation sequencing (NGS) is becoming an important tool for biomarker testing. In this study, we describe institutional experience of NGS analysis in non-small cell carcinoma (NSCLC). Materials and Methods: A cohort of 73 cases was identified from the institutional pathology archive in the period between November 2020 and December 2022. Results: Adenocarcinoma was the most common histologic type (91.8%). Most patients presented with stage IIIB and beyond (87.7%). Twenty-nine patients (39.7%) were evaluated at the time of initial diagnosis, while the others had received prior chemotherapy or targeted therapy. The most frequently mutated gene was EGFR (63%), and this was followed by TP53 (50.7%), KRAS (13.7%), RB1 (13.7%), and CDKN2A (13.7%). Clinically actionable mutations associated with a guideline-suggested targeted therapy were identified in 55 cases (75.3%) overall, and in 47.1% of cases excluding EGFR TKI-sensitizing mutation. Biomarkers other than EGFR TKI-sensitizing mutations were compared. Cases without TKI-sensitizing EGFR mutation had more level 1 or 2 biomarkers (excluding EGFR TKI-sensitizing mutations) than cases with TKI-sensitizing EGFR mutations (47.1% versus 20.1%, p = 0.016). Progressive disease was associated with co-occurrence of clinically actionable mutations (20.5% versus 0%, p < 0.05). Eight of the nine cases with co-occurring actionable genetic alternations had an EGFR mutation. After an NGS test, 46.1% of actionable or potentially actionable genetic alternations led to patients receiving a matched therapy. Conclusions: Our study demonstrated that NGS analysis identifies therapeutic targets and may guide treatment strategies in NSCLC. NGS tests may be advantageous over multiple single-gene tests for optimization of treatment plans, especially for those with non-EGFR mutations or those with progressive disease.


Subject(s)
Lung Neoplasms , Humans , Lung Neoplasms/drug therapy , Taiwan/epidemiology , ErbB Receptors/genetics , Mutation , High-Throughput Nucleotide Sequencing , Biomarkers , Protein Kinase Inhibitors/therapeutic use
2.
BMC Cancer ; 23(1): 599, 2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37380971

ABSTRACT

BACKGROUND: Dihydropyrimidinase-like 3 (DPYSL3) is a cytosolic phosphoprotein expressed in the nervous system and is crucial for neurogenesis. A previous study showed that increased DPYSL3 expression promotes tumour aggressiveness in pancreatic ductal adenocarcinoma, gastric cancer, and colon cancer. However, the role of DPYSL3 in affecting the biological behaviour of urothelial carcinoma (UC) is not yet understood. METHODS: A UC transcriptomic dataset from the Gene Expression Omnibus and the Urothelial Bladder Cancer (BLCA) dataset from The Cancer Genome Atlas were used for the in silico study. We collected 340 upper urinary tract urothelial carcinoma (UTUC) and 295 urinary bladder urothelial carcinoma (UBUC) samples for the immunohistochemical study. Fresh tumour tissue from 50 patients was used to examine the DPYSL3 mRNA level. In addition, urothelial cell lines with and without DPYSL3 knockdown were used for the functional study. RESULTS: The in silico study revealed that DPYSL3 correlated with advanced tumour stage and metastasis development while functioning primarily in the nucleobase-containing compound metabolic process (GO:0006139). DPYSL3 mRNA expression is significantly upregulated in advanced UC. Furthermore, overexpression of the DPYSL3 protein is significantly associated with the aggressive behaviour of UTUC and UBUC. DPYSL3 expression independently predicts disease-specific survival (DSS) and metastatic-free survival (MFS) in patients with UC. In non-muscle-invasive UBUC, DPYSL3 expression predicts local recurrence-free survival. UC cell lines with DPYSL3 knockdown exhibited decreased proliferation, migration, invasion, and human umbilical vein endothelial cells (HUVECs) tube formation but increased apoptosis and G1 arrest. Gene ontology enrichment analysis revealed that the enriched processes related to DPYSL3 overexpression in UC were tissue morphogenesis, cell mesenchyme migration, smooth muscle regulation, metabolic processes, and RNA processing. In vivo study revealed DPYSL3 knockdown in UC tumours significantly suppressed the growth of tumours and decreased MYC and GLUT1 protein expression. CONCLUSIONS: DPYSL3 promotes the aggressiveness of UC cells by changing their biological behaviours and is likely associated with cytoskeletal and metabolic process modifications. Furthermore, DPYSL3 protein overexpression in UC was associated with aggressive clinicopathological characteristics and independently predicted poor clinical outcomes. Therefore, DPYSL3 can be used as a novel therapeutic target for UC.


Subject(s)
Carcinoma, Transitional Cell , Pancreatic Neoplasms , Urinary Bladder Neoplasms , Humans , Urinary Bladder Neoplasms/genetics , Up-Regulation , Endothelial Cells , Prognosis , Muscle Proteins/genetics
3.
Int J Med Sci ; 19(10): 1615-1627, 2022.
Article in English | MEDLINE | ID: mdl-36185333

ABSTRACT

In recent years, translational research and pharmacological targeting of epigenetic modifications have become the focus of personalized therapy for patients with pancreatic cancer. Preclinical and clinical trials targeting post-translational modifications have been evaluated as monotherapy or in combination with standard chemotherapy. In this study, we selected 43 genes from seven families of chromatin-modifying enzymes and investigated the influences of epigenetic modifications and their interactions on pancreatic ductal adenocarcinoma (PDAC) using hierarchical clustering analysis. Our analysis also evaluated their effects on treatment modalities and regimens of chemotherapy for PDAC. RNA-seq data for a total of 177 patients with pancreatic cancer, obtained from The Cancer Genome Atlas database, were analyzed. Our results suggested that high-risk patients of survival significant chromatin remodeling-associated gene cluster (gene cluster 2), composed of histone methyltransferases, histone acetyltransferases, histone deacetylases, histone demethylases, and 10-11 translocation family, demonstrated inferior progression-free survival and overall survival in patients with PDAC, especially in men. Our novel biomarker, survival significant chromatin remodeling-associated gene cluster, showed superior prediction performance compared with the conventional TNM system. Overall, these findings suggest that epigenetic modifications and interactions play an important role in the prognosis and therapeutic response of patients with PDAC.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/genetics , Chromatin/genetics , Chromatin Assembly and Disassembly/genetics , Cluster Analysis , Histone Acetyltransferases/genetics , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Histone Methyltransferases/genetics , Histones/metabolism , Humans , Male , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Prognosis , Pancreatic Neoplasms
4.
Kaohsiung J Med Sci ; 40(3): 269-279, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38180299

ABSTRACT

Urothelial carcinoma (UC) is common cancer worldwide with a high prevalence in Taiwan, especially in the upper urinary tract, including the renal pelvis and ureter, also classifying as upper urinary tract urothelial carcinoma. Here, we aim to find a representative prognostic marker that strongly correlates to this type of carcinoma. Transforming growth factor beta-1-induced transcript 1 (TGFB1I1) is a cofactor of cellular TGF-ß1 and interacts with various nuclear receptors. The previous study showed that TGFB1I1 promotes focal adhesion formation, contributing to the epithelial-mesenchymal transition (EMT) with actin cytoskeleton and vimentin through TGFB1I1 regulation. We aim to reveal the role of TGFB1I1 in the tumorigenesis of UC. In silico and clinicopathological data of upper urinary tract urothelial carcinoma (UTUC) and urinary bladder urothelial carcinoma (UBUC) were accessed and analyzed for IHC staining regarding tumor characteristics, including survival outcome. Finally, an in vitro study was performed to demonstrate the biological changes of UC cells. In UTUC, overexpression of TGFB1I1 was significantly correlated with advanced tumor stage, papillary configuration, and frequent mitosis. Meanwhile, overexpression of TGFB1I1 was significantly correlated with advanced tumor stage and histological grade in UBUC. Moreover, the in vitro study shows that TGFB1I1 affects cell proliferation, viability, migration and wound healing. The EMT markers also decreased upon TGFB1I1 knockdown. In this study, we identified that TGFB1I1 regulates UC cell proliferation and viability and induces the EMT to facilitate cell migration in vitro, leading to its essential role in promoting tumor aggressiveness in both UTUC and UBUC.


Subject(s)
Carcinoma, Transitional Cell , Kidney Neoplasms , Ureteral Neoplasms , Urinary Bladder Neoplasms , Urologic Neoplasms , Humans , Urinary Bladder Neoplasms/pathology , Carcinoma, Transitional Cell/pathology , Urologic Neoplasms/genetics , Urologic Neoplasms/metabolism , Kidney Neoplasms/pathology , Cell Proliferation/genetics
5.
Biochem Biophys Res Commun ; 435(1): 107-12, 2013 May 24.
Article in English | MEDLINE | ID: mdl-23624506

ABSTRACT

Epigenetic regulation via abnormal activation of histone deacetylases (HDACs) is a mechanism that leads to cancer initiation and promotion. Activation of HDACs results in transcriptional upregulation of human telomerase reverse transcriptase (hTERT) and increases telomerase activity during cellular immortalization and tumorigenesis. However, the effects of HDAC inhibitors on the transcription of hTERT vary in different cancer cells. Here, we studied the effects of a novel HDAC inhibitor, AR42, on telomerase activity in a PTEN-null U87MG glioma cell line. AR42 increased hTERT mRNA in U87MG glioma cells, but suppressed total telomerase activity in a dose-dependent manner. Further analyses suggested that AR42 decreases the phosphorylation of hTERT via an Akt-dependent mechanism. Suppression of Akt phosphorylation and telomerase activity was also observed with PI3K inhibitor LY294002 further supporting the hypothesis that Akt signaling is involved in suppression of AR42-induced inhibition of telomerase activity. Finally, ectopic expression of a constitutive active form of Akt restored telomerase activity in AR42-treated cells. Taken together, our results demonstrate that the novel HDAC inhibitor AR42 can suppress telomerase activity by inhibiting Akt-mediated hTERT phosphorylation, indicating that the PI3K/Akt pathway plays an important role in the regulation of telomerase activity in response to this HDAC inhibitor.


Subject(s)
Histone Deacetylase Inhibitors/pharmacology , Phenylbutyrates/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Telomerase/antagonists & inhibitors , Cell Line, Tumor , Chromones/pharmacology , Enzyme-Linked Immunosorbent Assay , Gene Expression Regulation, Enzymologic/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Glioma/genetics , Glioma/metabolism , Glioma/pathology , Humans , Morpholines/pharmacology , Mutation , PTEN Phosphohydrolase/genetics , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide-3 Kinase Inhibitors , Phosphorylation/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/drug effects , Telomerase/genetics , Telomerase/metabolism
6.
Sci Rep ; 13(1): 13260, 2023 08 15.
Article in English | MEDLINE | ID: mdl-37582967

ABSTRACT

Interstitial fibrosis assessment by renal pathologists lacks good agreement, and we aimed to investigate its hidden properties and infer possible clinical impact. Fifty kidney biopsies were assessed by 9 renal pathologists and evaluated by intraclass correlation coefficients (ICCs) and kappa statistics. Probabilities of pathologists' assessments that would deviate far from true values were derived from quadratic regression and multilayer perceptron nonlinear regression. Likely causes of variation in interstitial fibrosis assessment were investigated. Possible misclassification rates were inferred on reported large cohorts. We found inter-rater reliabilities ranged from poor to good (ICCs 0.48 to 0.90), and pathologists' assessments had the worst agreements when the extent of interstitial fibrosis was moderate. 33.5% of pathologists' assessments were expected to deviate far from the true values. Variation in interstitial fibrosis assessment was found to be correlated with variation in interstitial inflammation assessment (r2 = 32.1%). Taking IgA nephropathy as an example, the Oxford T scores for interstitial fibrosis were expected to be misclassified in 21.9% of patients. This study demonstrated the complexity of the inter-rater reliability of interstitial fibrosis assessment, and our proposed approaches discovered previously unknown properties in pathologists' practice and inferred a possible clinical impact on patients.


Subject(s)
Glomerulonephritis, IGA , Kidney , Humans , Reproducibility of Results , Kidney/pathology , Glomerulonephritis, IGA/pathology , Fibrosis , Observer Variation
7.
Sci Rep ; 12(1): 15437, 2022 09 14.
Article in English | MEDLINE | ID: mdl-36104403

ABSTRACT

The tumor microenvironment represents one of the main obstacles in breast cancer treatment owing to the presence of heterogeneous stromal cells, such as adipose-derived stem cells (ADSCs), that may interact with breast cancer cells and promote cancer development. Resistin is an adipocytokine associated with adverse breast cancer progression; however, its underlying mechanisms in the context of the breast tumor microenvironment remain largely unidentified. Here, we utilized a transwell co-culture model containing patient-derived ADSCs and breast cancer cell lines to investigate their potential interaction, and observed that breast cancer cells co-cultured with resistin-treated ADSCs (R-ADSCs) showed enhanced cancer cell growth and metastatic ability. Screening by proteome arrays revealed that C-X-C motif chemokine ligand 5 (CXCL5) was released in the conditioned medium of the co-culture system, and phosphorylated ERK was increased in breast cancer cells after co-culture with R-ADSCs. Breast cancer cells treated with the recombinant proteins of CXCL5 showed similarly enhanced cell migration and invasion ability as occurred in the co-culture model, whereas application of neutralizing antibodies against CXCL5 reversed these phenomena. The orthotopic xenograft in mice by breast cancer cells after co-culture with R-ADSCs had a larger tumor growth and more CXCL5 expression than control. In addition, clinical analysis revealed a positive correlation between the expression of resistin and CXCL5 in both tumor tissues and serum specimens of breast cancer patients. The current study suggests that resistin-stimulated ADSCs may interact with breast cancer cells in the tumor microenvironment via CXCL5 secretion, leading to breast cancer cell malignancy.


Subject(s)
Breast Neoplasms , Resistin , Adipose Tissue/metabolism , Animals , Breast Neoplasms/pathology , Chemokine CXCL5/metabolism , Coculture Techniques , Female , Humans , Mice , Resistin/metabolism , Stem Cells , Tumor Microenvironment
8.
Biomedicines ; 10(9)2022 Sep 13.
Article in English | MEDLINE | ID: mdl-36140366

ABSTRACT

UMOD is the first identified and the most commonly mutated gene that causes autosomal dominant tubulointerstitial kidney disease (ADTKD). Recent studies have shown that ADTKD-UMOD is a relatively common cause of chronic kidney disease (CKD). However, the status of ADTKD-UMOD in Taiwan remains unknown. In this study, we identified three heterozygous UMOD missense variants, c.121T > C (p.Cys41Arg), c.179G > A (p.Gly60Asp), and c.817G > T (p.Val273Phe), in a total of 221 selected CKD families (1.36%). Two of these missense variants, p.Cys41Arg and p.Gly60Asp, have not been reported previously. In vitro studies showed that both uromodulin variants have defects in cell membrane trafficking and excretion to the culture medium. The structure model predicted altered disulfide bond formation in both variants, but only p.Gly60Asp was predicted to cause protein destabilization. Our findings extend the mutation spectrum and indicate that the ADTKD-UMOD contributed to a small but significant cause of CKD in the Taiwanese population.

9.
Cancers (Basel) ; 12(12)2020 Nov 26.
Article in English | MEDLINE | ID: mdl-33256011

ABSTRACT

Visfatin, an adipocytokine highly expressed in breast tumor tissues, is associated with breast cancer progression. Recent studies showed that adipocytokines mediate tumor development through adipocytokine tumor-stromal interactions in the tumor microenvironment. This study focused on the interaction between one key stromal constituent-tumor-associated macrophages-and visfatin. Pretreatment of THP-1 and peripheral blood mononuclear cells (PBMCs) with recombinant visfatin resulted in M2-polarization determined by CD163 and CD206 expression. Indirect co-culture with visfatin-treated THP-1 (V-THP-1) promoted the viability, migration, tumorsphere formation, EMT, and stemness of breast cancer cells. Cytokine array identified an increased CXCL1 secretion in V-THP-1 conditioned medium and recombinant CXCL1 enhanced cell migration and invasion, which were abrogated by the CXCL1-neutralizing antibody. Additionally, visfatin induced pERK in THP-1 cells and clinical samples confirmed a positive CXCL1/pERK correlation. In an orthotopic mouse model, the tumor bioluminescent signal of luciferase-expressing MDA-MB-231 (Luc-MDA-MB-231) cells co-cultured with V-THP-1 and the expression of proliferation marker Ki67 were significantly higher than that co-cultured with THP-1. Furthermore, tail vein-injected Luc-MDA-MB-231 pretreated with V-PBMCs conditioned medium metastasized to lungs more frequently compared to control, and this was reversed by CXCL1 blocking antibody. In summary, this study demonstrated that visfatin enhanced breast cancer progression via pERK/CXCL1 induction in macrophages.

10.
Oncogene ; 38(3): 317-331, 2019 01.
Article in English | MEDLINE | ID: mdl-30097606

ABSTRACT

Aged hepatocyte-specific-Mcl-1 knockout (MKO-hep) mice are prone to develop liver tumors mimicking human hepatocellular carcinoma (HCC). Here we reported that a protein named UDP-N-acetylglucosamine pyrophosphorylase-1-like-1 (Uap1l1) is upregulated in the liver of young MKO-hep mice without any macroscopically detectable tumor nodules and is prominently expressed in the hepatic tumors developed in the aged MKO-hep mice. Intriguingly, human UAP1L1 is also significantly upregulated in a distinct subset of HCC tissues and patients with upregulated expression of UAP1L1 appeared to have poor prognosis. Overexpression of UAP1L1 significantly promoted, whereas UAP1L1 knockdown markedly reduced the proliferation of human hepatoma cells both in vitro and in vivo. UAP1L1 shows ~59% sequence identity to UDP-N-acetylglucosamine pyrophosphorylase-1 (UAP1), which is directly involved in the synthesis of the sugar donor (UDP-GlcNac) for N-acetylglucosamine modification (O-GlcNAcylation) of proteins. However, unlike UAP1, UAP1L1 harbors very limited UDP-GlcNAc synthesis activity. Moreover, although both UAP1 and UAP1L1 are required for O-GlcNAc transferase (OGT)-mediated protein O-GlcNAcylation, they appear to function distinctly from each other. UAP1L1 directly interacts with OGT, but does not seem to be an OGT substrate. In addition, UAP1L1 alone is not sufficient to activate OGT activity in vitro, suggesting that UAP1L1 may function together with other proteins to modulate OGT activity in vivo. Lastly, UAP1L1 knockdown attenuated c-MYC O-GlcNAcylation and protein stability, and overexpression of c-MYC significantly rescued the proliferation defect of UAP1L1 knockdown HepG2 cells, suggesting that c-MYC is one downstream target of UAP1L1 that contributes to UAP1L1-mediated cell proliferation, at least in HepG2 cells.


Subject(s)
Carcinoma, Hepatocellular/enzymology , Intracellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/enzymology , Neoplasm Proteins/physiology , Nucleotidyltransferases/metabolism , Protein Processing, Post-Translational/physiology , Animals , Carcinoma, Hepatocellular/pathology , Cell Division , Enzyme Activation , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , Glycosylation , Hep G2 Cells , Humans , Intracellular Signaling Peptides and Proteins/genetics , Liver Neoplasms/pathology , Liver Neoplasms, Experimental/enzymology , Liver Neoplasms, Experimental/pathology , Mice , N-Acetylglucosaminyltransferases/metabolism , Nucleotidyltransferases/genetics , Prognosis , Protein Stability , Proto-Oncogene Proteins c-myc/metabolism , Transcriptome , Up-Regulation
11.
Autophagy ; 13(2): 371-385, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27875098

ABSTRACT

Autophagy is an evolutionarily conserved intracellular system that maintains cellular homeostasis by degrading and recycling damaged cellular components. The transcription factor HLH-30/TFEB-mediated autophagy has been reported to regulate tolerance to bacterial infection, but less is known about the bona fide bacterial effector that activates HLH-30 and autophagy. Here, we reveal that bacterial membrane pore-forming toxin (PFT) induces autophagy in an HLH-30-dependent manner in Caenorhabditis elegans. Moreover, autophagy controls the susceptibility of animals to PFT toxicity through xenophagic degradation of PFT and repair of membrane-pore cell-autonomously in the PFT-targeted intestinal cells in C. elegans. These results demonstrate that autophagic pathways and autophagy are induced partly at the transcriptional level through HLH-30 activation and are required to protect metazoan upon PFT intoxication. Together, our data show a new and powerful connection between HLH-30-mediated autophagy and epithelium intrinsic cellular defense against the single most common mode of bacterial attack in vivo.


Subject(s)
Autophagy , Bacterial Proteins/toxicity , Basic Helix-Loop-Helix Transcription Factors/metabolism , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/cytology , Caenorhabditis elegans/microbiology , Endotoxins/toxicity , Epithelium/metabolism , Hemolysin Proteins/toxicity , Animals , Autophagy/drug effects , Autophagy-Related Proteins/genetics , Autophagy-Related Proteins/metabolism , Bacillus thuringiensis Toxins , Base Sequence , Caenorhabditis elegans/drug effects , Caenorhabditis elegans/metabolism , Epithelium/drug effects , Epithelium/ultrastructure , Gene Expression Regulation/drug effects , Intestines/microbiology , Intestines/pathology , Models, Biological , Transcription, Genetic/drug effects
12.
Exp Gerontol ; 48(3): 371-9, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23318476

ABSTRACT

Aging is a process of gradual functional decline leading to death. Reactive oxygen species (ROS) not only contribute to oxidative stress and cell damage that lead to aging but also serve as signaling molecules. Sestrins are evolutionarily conserved in all multicellular organisms and are required for regenerating hyperoxidized forms of peroxiredoxins and ROS clearance. However, whether sestrins regulate longevity in metazoans is still unclear. Here, we demonstrated that SESN-1, the only sestrin ortholog in Caenorhabditis elegans, is a positive regulator of lifespan. sesn-1 gene mutant worms had significantly shorter lifespans compared to wild-type animals, and overexpression of sesn-1 prolonged lifespan. Moreover, sesn-1 was found to play a key role in defense against several life stressors, including heat, hydrogen peroxide and the heavy metal copper; and sesn-1 mutants expressed higher levels of ROS and showed a decline in body muscle function. Surprisingly, loss of sesn-1 did not weaken the innate immune function of the worms. Together, these results suggest that SESN-1 is required for normal lifespan and its function in muscle cells prevents muscle degeneration over a lifetime.


Subject(s)
Caenorhabditis elegans Proteins/physiology , Caenorhabditis elegans/physiology , Heat-Shock Proteins/physiology , Longevity/physiology , Aging/physiology , Animals , Animals, Genetically Modified , Caenorhabditis elegans Proteins/genetics , Heat-Shock Proteins/deficiency , Heat-Shock Proteins/genetics , Hot Temperature , Immunity, Innate/physiology , Locomotion/physiology , Muscle Strength/physiology , Oxidative Stress/physiology , RNA Interference , Reactive Oxygen Species/metabolism , Stress, Physiological/physiology
13.
PLoS One ; 5(3): e9494, 2010 Mar 02.
Article in English | MEDLINE | ID: mdl-20209166

ABSTRACT

Pore-forming toxins (PFTs) are the single largest class of bacterial virulence factors. The DAF-2 insulin/insulin-like growth factor-1 signaling pathway, which regulates lifespan and stress resistance in Caenorhabditis elegans, is known to mutate to resistance to pathogenic bacteria. However, its role in responses against bacterial toxins and PFTs is as yet unexplored. Here we reveal that reduction of the DAF-2 insulin-like pathway confers the resistance of Caenorhabditis elegans to cytolitic crystal (Cry) PFTs produced by Bacillus thuringiensis. In contrast to the canonical DAF-2 insulin-like signaling pathway previously defined for aging and pathogenesis, the PFT response pathway diverges at 3-phosphoinositide-dependent kinase 1 (PDK-1) and appears to feed into a novel insulin-like pathway signal arm defined by the WW domain Protein 1 (WWP-1). In addition, we also find that WWP-1 not only plays an important role in the intrinsic cellular defense (INCED) against PFTs but also is involved in innate immunity against pathogenic bacteria Pseudomonas aeruginosa and in lifespan regulation. Taken together, our data suggest that WWP-1 and DAF-16 function in parallel within the fundamental DAF-2 insulin/IGF-1 signaling network to regulate fundamental cellular responses in C. elegans.


Subject(s)
Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans Proteins/physiology , Caenorhabditis elegans/metabolism , Gene Expression Regulation , Gram-Positive Bacterial Infections/metabolism , Insulin/metabolism , Receptor, Insulin/metabolism , Ubiquitin-Protein Ligases/physiology , Aging , Animals , Bacillus thuringiensis/metabolism , Humans , Models, Biological , Mutation , RNA Interference , Signal Transduction , Ubiquitin-Protein Ligases/metabolism , Virulence Factors
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