15 results on '"Protein tyrosine kinase 2"'
Search Results
2. The mechanism of L1 cell adhesion molecule interacting with protein tyrosine kinase 2 to regulate the focal adhesion kinase–growth factor receptor-bound protein 2–son of sevenless–rat sarcoma pathway in the identification and treatment of type I high-risk endometrial cancer
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He, Wei, Liu, Wei, Liu, Xiumei, and Tan, Wenhua
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RISK assessment , *BIOLOGICAL models , *CELL migration , *SARCOMA , *COLONY-forming units assay , *CANCER invasiveness , *CELL proliferation , *CELLULAR signal transduction , *TUMOR markers , *CELL motility , *DESCRIPTIVE statistics , *ENDOMETRIAL tumors , *RATS , *LONGITUDINAL method , *CELL lines , *GENE expression , *MESSENGER RNA , *PROTEIN-tyrosine kinases , *GROWTH factors , *ANIMAL experimentation , *CYTOMETRY , *MATRIX metalloproteinases , *MICROBIOLOGICAL assay , *WESTERN immunoblotting , *STAINS & staining (Microscopy) , *VASCULAR cell adhesion molecule-1 , *CELL receptors , *MEMBRANE proteins , *DISEASE progression , *DISEASE risk factors - Abstract
Objective: The objective of this study was to investigate how L1 cell adhesion molecule (L1CAM) interacting with protein tyrosine kinase 2 (PTK2) affects endometrial cancer (EC) progression and determine its association with the focal adhesion kinase (FAK)–growth factor receptor-bound protein 2 (GRB2)–son of sevenless (SOS)–rat sarcoma (RAS) pathway. EC is a female cancer of major concern in the world, and its incidence has increased rapidly in recent years. L1CAM is considered a reliable marker of poor prognosis in patients with EC. Material and Methods: A single-center and prospective study was conducted using data from the Cancer Genome Atlas and samples from normal and EC tissues to explore the differential expression of L1CAM. Additional experimental models included human immortalized endometrial epithelium cells (hEECs) and EC cell lines such as KLE, RL95-2, and Ishikawa. L1CAM expression was regulated using lentiviruses designed for either overexpression or interference, and PTK2/focal adhesion kinase (FAK) signaling was inhibited with PF431396. Transfected KLE cells were injected into mice, and tumor growth was monitored over 14 days. Cellular proliferation and survival were assessed using cell counting kit, colony formation, and terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate (dUTP) nick-end labeling assays. Metastatic behavior was evaluated through Transwell assays for cell migration and invasion. The expression levels of matrix metallopeptidase (MMP) 2 and MMP9 were determined by Western blot. In addition, the activation of the FAK–GRB2–SOS–RAS pathway was examined by assessing the protein levels of FAK, GRB2, SOS, and RAS. Results: There was a significant difference in L1CAM expression between EC tumor tissues and normal tissues, and L1CAM messenger RNA (1.85-fold) and L1CAM protein (2.59-fold) were significantly more expressed in EC tissues (P < 0.01) than in normal tissues. The tumor growth of L1CAM overexpressing EC cells was faster than that of negative control EC cells (6.43 fold; P < 0.001). L1CAM promoted the expression of FAK (1.43-2.72-fold; P < 0.001); enhanced EC cell proliferation (P < 0.01), survival and motility (P < 0.001), migration (P < 0.001), and invasion (P < 0.001); and activated the FAK–GRB2–SOS–RAS pathway, all of which were reversed when FAK expression was not upregulated (P < 0.001). Conclusion: By upregulating PTK2 and its encoded protein FAK, L1CAM was found to promote tumor progression and increase the activation of the FAK–GRB2–SOS–RAS pathway. These findings establish L1CAM and PTK2 as reference genes for poor prognostic prediction in EC and as targets for EC therapy, providing a valuable basis for distinguishing between benign and malignant endometrial conditions and justifying the necessity of targeted therapeutic approaches. [ABSTRACT FROM AUTHOR]
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- 2024
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3. PTK2 is a potential biomarker and therapeutic target for EGFR- or TLRs-induced lung cancer progression via the regulation of the cross-talk between EGFR- and TLRs-mediated signals
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Ji Young Kim, Ji Hye Shin, Mi-Jeong Kim, Bongkum Choi, Yeeun Kang, Jimin Choi, Seo Hyun Kim, Dohee Kwan, Duk-Hwan Kim, Eunyoung Chun, and Ki-Young Lee
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Protein tyrosine kinase 2 ,Epidermal growth factor receptor ,Toll-like receptors ,Non-small cell lung cancer ,Defactinib ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Abstract Protein tyrosine kinase 2 (PTK2), epidermal growth factor receptor (EGFR), and toll-like receptor (TLRs) are amplified in non-small cell lung cancer (NSCLC). However, the functional and clinical associations between them have not been elucidated yet in NSCLC. By using microarray data of non-small cell lung cancer (NSCLC) tumor tissues and matched normal tissues of 42 NSCLC patients, the genetic and clinical associations between PTK2, EGFR, and TLRs were analyzed in NSCLC patients. To verify the functional association, we generated PTK2-knockout (PTK2-KO) lung cancer cells by using CRISPR-Cas9 gene editing method, and performed in vitro cancer progression assay, including 3D tumor spheroid assay, and in vivo xenografted NSG (NOD/SCID/IL-2Rγnull) mouse assay. Finally, therapeutic effects targeted to PTK2 in lung cancer in response to EGF and TLR agonists were verified by using its inhibitor (Defactinib). In summary, we identified that up-regulated PTK2 might be a reliable marker for EGFR- or TLRs-induced lung cancer progression in NSCLC patients via the regulation of the cross-talk between EGFR- and TLRs-mediated signaling. This study provides a theoretical basis for the therapeutic intervention of PTK2 targeting EGFR- or TLRs-induced lung cancer progression.
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- 2024
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4. PTK2 is a potential biomarker and therapeutic target for EGFR- or TLRs-induced lung cancer progression via the regulation of the cross-talk between EGFR- and TLRs-mediated signals.
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Kim, Ji Young, Shin, Ji Hye, Kim, Mi-Jeong, Choi, Bongkum, Kang, Yeeun, Choi, Jimin, Kim, Seo Hyun, Kwan, Dohee, Kim, Duk-Hwan, Chun, Eunyoung, and Lee, Ki-Young
- Abstract
Protein tyrosine kinase 2 (PTK2), epidermal growth factor receptor (EGFR), and toll-like receptor (TLRs) are amplified in non-small cell lung cancer (NSCLC). However, the functional and clinical associations between them have not been elucidated yet in NSCLC. By using microarray data of non-small cell lung cancer (NSCLC) tumor tissues and matched normal tissues of 42 NSCLC patients, the genetic and clinical associations between PTK2, EGFR, and TLRs were analyzed in NSCLC patients. To verify the functional association, we generated PTK2-knockout (PTK2-KO) lung cancer cells by using CRISPR-Cas9 gene editing method, and performed in vitro cancer progression assay, including 3D tumor spheroid assay, and in vivo xenografted NSG (NOD/SCID/IL-2Rγ
null ) mouse assay. Finally, therapeutic effects targeted to PTK2 in lung cancer in response to EGF and TLR agonists were verified by using its inhibitor (Defactinib). In summary, we identified that up-regulated PTK2 might be a reliable marker for EGFR- or TLRs-induced lung cancer progression in NSCLC patients via the regulation of the cross-talk between EGFR- and TLRs-mediated signaling. This study provides a theoretical basis for the therapeutic intervention of PTK2 targeting EGFR- or TLRs-induced lung cancer progression. [ABSTRACT FROM AUTHOR]- Published
- 2024
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5. HGF-mediated elevation of ETV1 facilitates hepatocellular carcinoma metastasis through upregulating PTK2 and c-MET
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Tongyue Zhang, Yijun Wang, Meng Xie, Xiaoyu Ji, Xiangyuan Luo, Xiaoping Chen, Bixiang Zhang, Danfei Liu, Yangyang Feng, Mengyu Sun, Wenjie Huang, and Limin Xia
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E-twenty-six transformation-specific variant 1 ,Tyrosine protein kinase Met ,Protein tyrosine kinase 2 ,Defactinib ,Capmatinib ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Metastasis is a major determinant of death in patients with hepatocellular carcinoma (HCC). Dissecting key molecular mediators that promote this malignant feature may help yield novel therapeutic insights. Here, we investigated the role of E-twenty-six transformation-specific variant 1 (ETV1), a member of the E-twenty-six transformation-specific (ETS) family, in HCC metastasis. Methods The clinical significance of ETV1 and its target genes in two independent cohorts of HCC patients who underwent curative resection were assessed by Kaplan–Meier analysis and Multivariate Cox proportional hazards model. Luciferase reporter assay and chromatin immunoprecipitation assay were used to detect the transcriptional regulation of target gene promoters by ETV1. The effect of ETV1 on invasiveness and metastasis of HCC were detected by transwell assays and the orthotopically metastatic model. Results ETV1 expression was frequently elevated in human HCC specimens. Increased ETV1 expression was associated with the malignant biological characteristics and poor prognosis of HCC patients. ETV1 facilitated invasion and metastasis of HCC cells in vitro and in vivo. Mechanistically, ETV1 promoted HCC metastasis via upregulating metastasis-related genes, including protein tyrosine kinase 2 (PTK2) and MET. Down-regulated the expression of PTK2 or tyrosine protein kinase Met (c-MET) decreased ETV1-mediated HCC metastasis. Hepatocyte growth factor (HGF) upregulated ETV1 expression through activating c-MET-ERK1/2-ELK1 pathway. Notably, in two independent cohorts, patients with positive coexpression of ETV1/PTK2 or ETV1/c-MET had worse prognosis. Furthermore, the combination of PTK2 inhibitor defactinib and c-MET inhibitor capmatinib significantly suppressed HCC metastasis induced by ETV1. Conclusion This study uncovers functional and prognostic roles for ETV1 in HCC and exposes a positive feedback loop of HGF-ERK1/2-ETV1-c-MET. Targeting this pathway may provide a potential therapeutic intervention for ETV1-overexpressing HCC.
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- 2022
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6. HGF-mediated elevation of ETV1 facilitates hepatocellular carcinoma metastasis through upregulating PTK2 and c-MET.
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Zhang, Tongyue, Wang, Yijun, Xie, Meng, Ji, Xiaoyu, Luo, Xiangyuan, Chen, Xiaoping, Zhang, Bixiang, Liu, Danfei, Feng, Yangyang, Sun, Mengyu, Huang, Wenjie, and Xia, Limin
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PROTEIN-tyrosine kinases ,HEPATOCELLULAR carcinoma ,HEPATOCYTE growth factor ,PROPORTIONAL hazards models ,METASTASIS - Abstract
Background: Metastasis is a major determinant of death in patients with hepatocellular carcinoma (HCC). Dissecting key molecular mediators that promote this malignant feature may help yield novel therapeutic insights. Here, we investigated the role of E-twenty-six transformation-specific variant 1 (ETV1), a member of the E-twenty-six transformation-specific (ETS) family, in HCC metastasis. Methods: The clinical significance of ETV1 and its target genes in two independent cohorts of HCC patients who underwent curative resection were assessed by Kaplan–Meier analysis and Multivariate Cox proportional hazards model. Luciferase reporter assay and chromatin immunoprecipitation assay were used to detect the transcriptional regulation of target gene promoters by ETV1. The effect of ETV1 on invasiveness and metastasis of HCC were detected by transwell assays and the orthotopically metastatic model. Results: ETV1 expression was frequently elevated in human HCC specimens. Increased ETV1 expression was associated with the malignant biological characteristics and poor prognosis of HCC patients. ETV1 facilitated invasion and metastasis of HCC cells in vitro and in vivo. Mechanistically, ETV1 promoted HCC metastasis via upregulating metastasis-related genes, including protein tyrosine kinase 2 (PTK2) and MET. Down-regulated the expression of PTK2 or tyrosine protein kinase Met (c-MET) decreased ETV1-mediated HCC metastasis. Hepatocyte growth factor (HGF) upregulated ETV1 expression through activating c-MET-ERK1/2-ELK1 pathway. Notably, in two independent cohorts, patients with positive coexpression of ETV1/PTK2 or ETV1/c-MET had worse prognosis. Furthermore, the combination of PTK2 inhibitor defactinib and c-MET inhibitor capmatinib significantly suppressed HCC metastasis induced by ETV1. Conclusion: This study uncovers functional and prognostic roles for ETV1 in HCC and exposes a positive feedback loop of HGF-ERK1/2-ETV1-c-MET. Targeting this pathway may provide a potential therapeutic intervention for ETV1-overexpressing HCC. [ABSTRACT FROM AUTHOR]
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- 2022
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7. Herbal formula YGJDSJ inhibits anchorage-independent growth and induces anoikis in hepatocellular carcinoma Bel-7402 cells
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Bing Hu, Tong Zhang, Hong-Mei An, Jia-Lu Zheng, Xia Yan, and Xiao-Wei Huang
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Hepatocellular carcinoma ,Chinese herb ,Anoikis ,Caspases ,Reactive oxygen species ,Protein tyrosine kinase 2 ,Other systems of medicine ,RZ201-999 - Abstract
Abstract Background Based on clinical medications and related studies, we established a Yang-Gan Jie-Du Sang-Jie (YGJDSJ) herbal formula for hepatocarcinoma treatment. In present study, we evaluated the anti-cancer potential of YGJDSJ on suspension-grown human hepatocellular carcinoma Bel-7402 cells. Methods Bel-7402 cells were cultured in poly(2-hydroxyethyl methacrylate) (poly-HEMA) coated plates and treated with YGJDSJ. Anchorage-independent cell growth was detected by cell Counting Kit-8 (CCK-8) assay and soft agar colony formation assay. Anoikis was detected by ethdium homodimer-1 (EthD-1) staining and flow cytometry analysis. Caspases activities were detected by the cleavage of chromogenic substrate. Reactive oxygen species (ROS) was detected by 2′,7′-dichlorofluorescin diacetate (DCFH-DA) staining. Protein expression and phosphorylation was identified by western blot. Protein expression was knocked-down by siRNA. Results YGJDSJ inhibited the proliferation of Bel-7402 cells in poly-HEMA coated plates and anchorage-independent growth of Bel-7402 cells in soft agar. YGJDSJ also induced anoikis in Bel-7402 cells as indicated by EthD-1 staining and flow cytometry analysis. YGJDSJ activated caspase-3, − 8, and − 9 in suspension-grown Bel-7402 cells. The pan-caspase inhibitor Z-VAD-FMK significantly abrogated the effects of YGJDSJ on anoikis in suspension-grown Bel-7402 cells. In addition, YGJDSJ increased ROS in suspension-grown Bel-7402 cells. The ROS scavenger N-acetyl-L-cysteine (NAC) partially attenuated YGJDSJ-induced activation of caspase-3, − 8 and − 9 and anoikis in suspension-grown Bel-7402 cells. Furthermore, YGJDSJ inhibited expression and phosphorylation of protein tyrosine kinase 2 (PTK2) in suspension-grown Bel-7402 cells. Over-expression of PTK2 significantly abrogated YGJDSJ induced anoikis. Conclusions YGJDSJ inhibits anchorage-independent growth and induce caspase-mediated anoikis in Bel-7402 cells, and may relate to ROS generation and PTK2 downregulation.
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- 2018
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8. Herbal formula YGJDSJ inhibits anchorage-independent growth and induces anoikis in hepatocellular carcinoma Bel-7402 cells.
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Hu, Bing, Zhang, Tong, An, Hong-Mei, Zheng, Jia-Lu, Yan, Xia, and Huang, Xiao-Wei
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CELL proliferation ,REACTIVE oxygen species ,APOPTOSIS ,CELL culture ,CELL lines ,CYTOLOGICAL techniques ,ENZYME inhibitors ,FLOW cytometry ,GENE expression ,GENETIC techniques ,HEPATOCELLULAR carcinoma ,HERBAL medicine ,CHINESE medicine ,PHOSPHORYLATION ,PROTEIN-tyrosine kinases ,RNA ,STAINS & staining (Microscopy) ,WESTERN immunoblotting - Abstract
Background: Based on clinical medications and related studies, we established a Yang-Gan Jie-Du Sang-Jie (YGJDSJ) herbal formula for hepatocarcinoma treatment. In present study, we evaluated the anti-cancer potential of YGJDSJ on suspension-grown human hepatocellular carcinoma Bel-7402 cells. Methods: Bel-7402 cells were cultured in poly(2-hydroxyethyl methacrylate) (poly-HEMA) coated plates and treated with YGJDSJ. Anchorage-independent cell growth was detected by cell Counting Kit-8 (CCK-8) assay and soft agar colony formation assay. Anoikis was detected by ethdium homodimer-1 (EthD-1) staining and flow cytometry analysis. Caspases activities were detected by the cleavage of chromogenic substrate. Reactive oxygen species (ROS) was detected by 2',7'-dichlorofluorescin diacetate (DCFH-DA) staining. Protein expression and phosphorylation was identified by western blot. Protein expression was knocked-down by siRNA. Results: YGJDSJ inhibited the proliferation of Bel-7402 cells in poly-HEMA coated plates and anchorage- independent growth of Bel-7402 cells in soft agar. YGJDSJ also induced anoikis in Bel-7402 cells as indicated by EthD-1 staining and flow cytometry analysis. YGJDSJ activated caspase-3, - 8, and - 9 in suspension-grown Bel-7402 cells. The pan-caspase inhibitor Z-VAD-FMK significantly abrogated the effects of YGJDSJ on anoikis in suspension-grown Bel-7402 cells. In addition, YGJDSJ increased ROS in suspension-grown Bel-7402 cells. The ROS scavenger N-acetyl-L-cysteine (NAC) partially attenuated YGJDSJ-induced activation of caspase-3, - 8 and - 9 and anoikis in suspension-grown Bel-7402 cells. Furthermore, YGJDSJ inhibited expression and phosphorylation of protein tyrosine kinase 2 (PTK2) in suspension-grown Bel-7402 cells. Over-expression of PTK2 significantly abrogated YGJDSJ induced anoikis. Conclusions: YGJDSJ inhibits anchorage-independent growth and induce caspase-mediated anoikis in Bel-7402 cells, and may relate to ROS generation and PTK2 downregulation. [ABSTRACT FROM AUTHOR]
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- 2018
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9. Polymorphisms in PTK2 are associated with skeletal muscle specific force: an independent replication study.
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Stebbings, Georgina, Williams, A., Morse, C., Day, S., Stebbings, Georgina K, Williams, A G, Morse, C I, and Day, S H
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MUSCLE strength , *PROTEIN-tyrosine kinases , *VASTUS lateralis , *FOCAL adhesion kinase , *GENETIC polymorphisms , *SKELETAL muscle physiology , *GENES , *TRANSFERASES , *PHENOTYPES , *GENETIC carriers , *GENOTYPES - Abstract
Purpose: The aim of the study was to investigate two single nucleotide polymorphisms (SNP) in PTK2 for associations with human muscle strength phenotypes in healthy men.Methods: Measurement of maximal isometric voluntary knee extension (MVCKE) torque, net MVCKE torque and vastus lateralis (VL) specific force, using established techniques, was completed on 120 Caucasian men (age = 20.6 ± 2.3 year; height = 1.79 ± 0.06 m; mass = 75.0 ± 10.0 kg; mean ± SD). All participants provided either a blood (n = 96) or buccal cell sample, from which DNA was isolated and genotyped for the PTK2 rs7843014 A/C and rs7460 A/T SNPs using real-time polymerase chain reaction.Results: Genotype frequencies for both SNPs were in Hardy-Weinberg equilibrium (X 2 ≤ 1.661, P ≥ 0.436). VL specific force was 8.3% higher in rs7843014 AA homozygotes than C-allele carriers (P = 0.017) and 5.4% higher in rs7460 AA homozygotes than T-allele carriers (P = 0.029). No associations between either SNP and net MVCKE torque (P ≥ 0.094) or peak MVCKE torque (P ≥ 0.107) were observed.Conclusions: These findings identify a genetic contribution to the inter-individual variability within muscle specific force and provides the first independent replication, in a larger Caucasian cohort, of an association between these PTK2 SNPs and muscle specific force, thus extending our understanding of the influence of genetic variation on the intrinsic strength of muscle. [ABSTRACT FROM AUTHOR]- Published
- 2017
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10. HMGB1-mediated elevation of KLF7 facilitates hepatocellular carcinoma progression and metastasis through upregulating TLR4 and PTK2.
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Feng W, Chen J, Huang W, Wang G, Chen X, Duan L, Yin Y, Chen X, Zhang B, Sun M, Luo X, Nie Y, Fan D, Wu K, and Xia L
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- Humans, Focal Adhesion Kinase 1, Inflammation etiology, Phosphatidylinositol 3-Kinases, Toll-Like Receptor 4 genetics, Toll-Like Receptor 4 metabolism, Carcinoma, Hepatocellular pathology, HMGB1 Protein genetics, HMGB1 Protein metabolism, Kruppel-Like Transcription Factors genetics, Liver Neoplasms pathology
- Abstract
Background: Metastasis is a major cause of HCC-related deaths with no effective pharmacotherapies. Chronic inflammation promotes HCC dissemination, however, its underlying mechanisms are not fully understood. Here, we investigated the role of Krüppel-like factor 7 (KLF7) in inflammation-provoked HCC metastasis and proposed therapeutic strategies for KLF7-positive patients. Methods: The expression of KLF7 in human HCC specimens were examined by immunohistochemistry and quantitative real-time PCR. The luciferase reporter assays and chromatin immunoprecipitation assays were conducted to explore the transcriptional regulation related to KLF7. Orthotopic xenograft models and DEN/CCl
4 -induced HCC models were established to evaluate HCC progression and metastasis. Results: KLF7 overexpression promotes HCC metastasis through transactivating toll-like receptor 4 (TLR4) and protein tyrosine kinase 2 (PTK2) expression. High mobility group box 1 (HMGB1) upregulates KLF7 expression through the TLR4/advanced glycosylation end-product specific receptor (RAGE)-PI3K-AKT-NF-κB pathway, forming an HMGB1-KLF7-TLR4 positive feedback loop. The HMGB1-KLF7-TLR4/PTK2 axis is gradually activated during the progression of inflammation-HCC transition. Genetic depletion of KLF7 impedes HMGB1-mediated HCC progression and metastasis. The combined application of TLR4 inhibitor TAK-242 and PTK2 inhibitor defactinib alleviates HCC progression and metastasis induced by the HMGB1-KLF7 axis. In human HCCs, KLF7 expression is positively correlated with cytoplasmic HMGB1, p-p65, TLR4, and PTK2 levels, and patients positively co-expressing HMGB1/KLF7, p-p65/KLF7, KLF7/TLR4 or KLF7/PTK2 exhibit the worst prognosis. Conclusions: HMGB1-induced KLF7 overexpression facilitates HCC progression and metastasis by upregulating TLR4 and PTK2. Genetic ablation of KLF7 via AAV gene therapy and combined blockade of TLR4 and PTK2 represents promising therapy strategies for KLF7-positive HCC patients., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)- Published
- 2023
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11. Regulation of homocysteine-induced MMP-9 by ERK1/2 pathway.
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Moshal, Karni S., Sen, Utpal, Tyagi, Neetu, Henderson, Brooke, Steed, Mesia, Ovechkin, Alexander V., and Tyagi, Suresh C.
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EXTRACELLULAR matrix proteins , *METALLOPROTEINASES , *ENDOTHELIUM , *HOMOCYSTEINE , *PHOSPHORYLATION , *PROTEIN kinases , *CELLULAR signal transduction - Abstract
Homocysteine (Hey) induces matrix metalloproteinase (MMP)-9 in microvascular endothehal cells (MVECs). We hypothesized that the ERK1/2 signaling pathway is involved in Hey-mediated MMP-9 expression. In cultured MVECs, Hey induced activation of ERK, which was blocked by PD-98059 and U0126 (MEK inhibitors). Pretreatment with BAPTA-AM, staurosporine (PKC inhibitor), or Gö6976 (specific inhibitor for Ca2+-dependent PKC) abrogated ERK phosphorylation, suggesting the role of Ca2+ and Ca2+-dependent PKC in Hey-induced ERK activation. ERK phosphorylation was suppressed by pertussis toxin (PTX), suggesting the involvement of G protein-coupled receptors (GPCRs) in initiating signal transduction by Hey and leading to ERK activation. Pretreatment of MVECs with genistein, BAPTA-AM, or thapsigargin abrogated Hey-induced ERK activation, suggesting the involvement of the PTK pathway in Hey-induced ERK activation, which was mediated by intracellular Ca2+ pool depletion. ERK activation was attenuated by preincubation with N-acetylcysteine (NAC) and SOD, suggesting the role of oxidation in Hey-induced ERK activation. Pretreatment with an ERKI/2 blocker (PD-98059), staurosporine, folate, or NAC modulated Hey-induced MMP-9 activation as measured using zymography. Our results provide evidence that Hey triggers the PTX-sensitive ERK1/2 signaling pathway, which is involved in the regulation of MMP-9 in MVECs. [ABSTRACT FROM AUTHOR]
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- 2006
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12. Reactive oxygen species mediate Endothelin-1-induced activation of ERK1/2, PKB, and Pyk2 signaling, as well as protein synthesis, in vascular smooth muscle cells
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Daou, Grace Bou and Srivastava, Ashok K.
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CYTOKINES , *MUSCLES , *CELLS , *PHOTOSYNTHETIC oxygen evolution - Abstract
Reactive oxygen species (ROS) have been shown to mediate the effects of several growth factors and vasoactive peptides, such as epidermal growth factor, platelet-derived growth factor, and angiotensin II (AII). Endothelin-1 (ET-1) is a vasoactive peptide which also exhibits mitogenic activity in vascular smooth muscle cells (VSMCs), and is believed to contribute to the pathogenesis of vascular abnormalities such as atherosclerosis, hypertension, and restenosis after angioplasty. However, a possible role for ROS generation in mediating the ET-1 response on extracellular signal-regulated kinases 1 and 2 (ERK1/2), protein kinase B (PKB), and protein tyrosine kinase 2 (Pyk2), key components of the growth-promoting and proliferative signaling pathways, has not been examined in detail. Our aim was to investigate the involvement of ROS in ET-1-mediated activation of ERK1/2, PKB, and Pyk2 in A-10 VSMCs. ET-1 stimulated ERK1/2, PKB, and Pyk2 phosphorylation in a dose- and time-dependent manner. Pretreatment of A-10 VSMCs with diphenyleneiodonium (DPI), an inhibitor of reduced nicotinamide adenine dinucleotide phosphate oxidase, attenuated ET-1-enhanced ERK1/2, PKB, and Pyk2 phosphorylation. In addition, in parallel with an inhibitory effect on the above signaling components, DPI also blocked ET-1-induced protein synthesis. ET-1 was also found to increase ROS production, which was suppressed by DPI treatment. N-Acetylcysteine, a ROS scavenger, exhibited a response similar to that of DPI and inhibited ET-1-stimulated ERK1/2, PKB, and Pyk2 phosphorylation. These results demonstrate that ROS are critical mediators of ET-1-induced signaling events linked to growth-promoting proliferative and hypertrophic pathways in VSMCs. [Copyright &y& Elsevier]
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- 2004
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13. Changes in rat frontal cortex gene expression following chronic cocaine
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Freeman, Willard M., Brebner, Karen, Lynch, Wendy J., Patel, Kruti M., Robertson, Daniel J., Roberts, David C.S., and Vrana, Kent E.
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PROTEIN microarrays , *PROTEIN-tyrosine kinases - Abstract
Alterations in gene expression caused by repeated cocaine administration have been implicated in the long-term behavioral aspects of cocaine abuse. The frontal cortex mediates reinforcement, sensory, associative, and executive functions and plays an important role in the mesocortical dopamine reinforcement system. Repeated cocaine administration causes changes in frontal cortex gene expression that may lead to changes in the behaviors subserved by this brain region. Rats treated non-contingently with a binge model of cocaine (45 mg/kg/day, i.p.) for 14 days were screened for changes in relative mRNA abundance in the frontal cortex by cDNA hybridization arrays. To confirm changes, immunoreactive protein was measured (via protein-specific immunoblots) in a second group of identically-treated animals. Protein levels of protein tyrosine kinase 2 (PYK2), activity-regulated cytoskeletal protein (ARC), as well as an antigen related to nerve growth factor I-B (NGFI-B-RA) were shown to be significantly induced after cocaine administration. Levels of NGFI-B mRNA were confirmed by real-time RT–PCR to be increased with cocaine administration. These observations are similar to previously reported cocaine-responsive changes in gene expression but novel to the frontal cortex. This study also validates the use of hybridization arrays for screening of neuronal gene expression changes and the utility of relative protein quantification as a post-hoc confirmation tool. [Copyright &y& Elsevier]
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- 2002
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14. Dysregulation of focal adhesion kinase upon Toxoplasma gondii infection facilitates parasite translocation across polarised primary brain endothelial cell monolayers
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Ross, Emily C., Olivera, Gabriela C., Barragan, Antonio, Ross, Emily C., Olivera, Gabriela C., and Barragan, Antonio
- Abstract
The apicomplexan parasite Toxoplasma gondii invades tissues and traverses non-permissive biological barriers in infected humans and other vertebrates. Following ingestion, the parasite penetrates the intestinal wall and disseminates to immune-privileged sites such as the brain parenchyma, after crossing the blood-brain barrier. In the present study, we have established a protocol for high-purification of primary mouse brain endothelial cells to generate stably polarised monolayers that allowed assessment of cellular barrier traversal by T. gondii. We report that T. gondii tachyzoites translocate across polarised monolayers of mouse brain endothelial cells and human intestinal Caco2 cells without significantly perturbing barrier impermeability and with minimal change in transcellular electrical resistance. In contrast, challenge with parasite lysate or LPS increased barrier permeability by destabilising intercellular tight junctions (TJs) and accentuated transmigration of T. gondii. Conversely, reduced phosphorylation of the TJ-regulator focal adhesion kinase (FAK) was observed dose-dependently upon challenge of monolayers with live T. gondii but not with parasite lysate or LPS. Pharmacological inhibition of FAK phosphorylation reversibly altered barrier integrity and facilitated T. gondii translocation. Finally, gene silencing of FAK by shRNA facilitated transmigration of T. gondii across epithelial and endothelial monolayers. Jointly, the data demonstrate that T. gondii infection transiently alters the TJ stability through FAK dysregulation to facilitate transmigration. This work identifies the implication of the TJ regulator FAK in the transmigration of T. gondii across polarised cellular monolayers and provides novel insights in how microbes overcome the restrictiveness of biological barriers.
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- 2019
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15. Overexpression of BACH1 mediated by IGF2 facilitates hepatocellular carcinoma growth and metastasis via IGF1R and PTK2.
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Xie M, Sun M, Ji X, Li D, Chen X, Zhang B, Huang W, Zhang T, Wang Y, Tian D, and Xia L
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- Cell Line, Tumor, Cell Movement genetics, Cell Proliferation genetics, Humans, Neoplasm Metastasis, Basic-Leucine Zipper Transcription Factors biosynthesis, Basic-Leucine Zipper Transcription Factors genetics, Basic-Leucine Zipper Transcription Factors metabolism, Carcinoma, Hepatocellular genetics, Carcinoma, Hepatocellular metabolism, Carcinoma, Hepatocellular pathology, Focal Adhesion Kinase 1 genetics, Focal Adhesion Kinase 1 metabolism, Insulin-Like Growth Factor II genetics, Insulin-Like Growth Factor II metabolism, Liver Neoplasms genetics, Liver Neoplasms metabolism, Liver Neoplasms pathology, Receptor, IGF Type 1 genetics, Receptor, IGF Type 1 metabolism
- Abstract
Background: Accumulating studies manifest that BTB and CNC homology 1 (BACH1) facilitates multiple malignancies progression and metastasis, and targeting the BACH1 pathway enhances antitumor efficacy. Nevertheless, the exact mechanism of BACH1 promoting growth and metastasis and its therapeutic significance in hepatocellular carcinoma (HCC) remain unclear. Methods: The expression of BACH1 in human HCC specimens and HCC cell lines was analyzed by quantitative RT-PCR (RT-qPCR), western blot, and immunohistochemistry (IHC). The invasiveness and metastasis of HCC cells in vitro and in vivo were evaluated using transwell assays and orthotopic xenograft models. The luciferase reporter assays and chromatin immunoprecipitation (ChIP) assays were performed to explore the transcriptional regulation of insulin-like growth factor 1 receptor ( IGF1R ) and protein tyrosine kinase 2 ( PTK2 ) by BACH1. Results: BACH1 was prominently upregulated in human HCC samples and elevated BACH1 expression was associated with poor overall survival (OS) and high recurrence rates of HCC patients. BACH1 facilitated growth and metastasis of HCC by upregulating cell motility-related genes IGF1R and PTK2 . Notably, insulin-like growth factor 2 (IGF2), the ligand of IGF1R, in turn upregulated BACH1 expression through the IGF1R-ERK1/2-ETS1 cascades, thus forming a positive feedback loop to provoke HCC growth and metastasis. Moreover, combining IGF1R inhibitor linsitinib with PTK2 inhibitor defactinib prominently suppressed BACH1-mediated HCC growth and metastasis. Conclusions: These results demonstrated the tumorigenic and pro-metastatic role of BACH1 in HCC, which could be a promising biomarker for predicting poor prognosis and selecting patients who could benefit from combination therapy of IGF1R-targeted and PTK2-directed., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)
- Published
- 2022
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