RESUMO
Bladder cancer (BC) is a malignant tumor of the urinary system with high mortality and recurrence rates. Proteasome subunit type 4 (PSMB4) is highly expressed and has been identified as having oncogenic properties in a variety of cancer types. This study aimed to explore the effect of PSMB4 knockdown on the survival, migration, and angiogenesis of human bladder cancer cells with different degrees of malignancy. We analyzed the effects of PSMB4 knockdown in bladder cancer cells and endothelial cells in the tumor microenvironment. PSMB4 was highly expressed in patients with low- and high-grade urothelial carcinoma. Inhibition of PSMB4 reduced protein expression of focal adhesion kinase (FAK) and myosin light chain (MLC), leading to reduced migration. Furthermore, the suppression of PSMB4 decreased the levels of vascular endothelial factor B (VEGF-B), resulting in lower angiogenic abilities in human bladder cancer cells. PSMB4 inhibition affected the migratory ability of HUVECs and reduced VEGFR2 expression, consequently downregulating angiogenesis. In the metastatic animal model, PSMB4 knockdown reduced the relative volumes of lung tumors. Our findings suggest the role of PSMB4 as a potential target for therapeutic strategies against human bladder cancer.
Assuntos
Movimento Celular , Neovascularização Patológica , Complexo de Endopeptidases do Proteassoma , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/metabolismo , Movimento Celular/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Linhagem Celular Tumoral , Animais , Camundongos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Técnicas de Silenciamento de Genes , Regulação Neoplásica da Expressão Gênica , Microambiente Tumoral/genética , Masculino , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Feminino , Angiogênese , Cisteína EndopeptidasesRESUMO
BACKGROUND: Glioblastoma (GBM) is notorious for the aggressive behaviors and easily results in chemo-resistance. Studies have shown that the use of herbal medicines as treatments for GBM as limited by the blood-brain barrier (BBB) and glioma stem cells. PURPOSE: The aim of this study was to investigate the relationship between GBM suppression and α-terpineol, the monoterpenoid alcohol derived from Eucalyptus glubulus and Pinus merkusii. STUDY DESIGN: Using serial in-vitro and in-vivo studies to confirm the mechanism of α-terpineol on down-regulating GBM development. METHODS: The 3-[4,5-dimethylthiazol-2-yl)]-2,5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate IC50 of α-terpineol to inhibit GBM cell survival. In order to evaluate the impact of GBM aggressive behaviors by α-terpineol, the analysis of cell migration, invasion and colony formation were implemented. In addition, the ability of tumor spheres and WB of CD44 and OCT3/4 were evaluated under the impression of α-terpineol decreased GBM stemness. The regulation of neoangiogenesis by α-terpineol via the WB of angiogenic factors and human umbilical vein endothelial cells (HUVEC) tube assay. To survey the decided factors of α-terpineol downregulating GBM chemoresistance depended on the impact of O6-methylguanine-DNA methyltransferase (MGMT) expression and autophagy-related factors activation. Additionally, WB and quantitative real-time polymerase chain reaction (qRT/PCR) of KDEL (Lys-Asp-Glu-Leu) containing 2 (KDELC2), endoplasmic reticulum (ER) stress, phosphoinositide 3-kinase (PI3k), mammalian target of rapamycin (mTOR) and mitogen-activated protein kinase (MAPK) cascade signaling factors were examined to explore the mechanism of α-terpineol inhibiting GBM viability. Finally, the orthotopic GBM mouse model was applied to prove the efficacy and toxicity of α-terpineol on regulating GBM survival. RESULTS: α-terpineol significantly suppressed GBM growth, migration, invasion, angiogenesis and temozolomide (TMZ) resistance. Furthermore, α-terpineol specifically targeted KDELC2 to downregulate Notch and PI3k/mTOR/MAPK signaling pathway. Finally, we also demonstrated that α-terpineol could penetrate the BBB to inhibit GBM proliferation, which resulted in reduced cytotoxicity to vital organs. CONCLUSION: Compared to published literatures, we firstly proved α-terpineol possessed the capability to inhibit GBM through various mechanisms and potentially decreased the occurrence of chemoresistance, making it a promising alternative therapeutic option for GBM in the future.
Assuntos
Neoplasias Encefálicas , Monoterpenos Cicloexânicos , Glioblastoma , Camundongos , Animais , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Fosfatidilinositol 3-Quinases , Células Endoteliais/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Serina-Treonina Quinases TOR , Fosfatidilinositol 3-Quinase , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , MamíferosRESUMO
The ability of bladder cancer to invade and metastasize often leads to poor prognosis in bladder cancer patients. The aim of this study was to evaluate the effect of the farnesoid X receptor (FXR) agonist GW4064 on the migration and invasion of human bladder cancer cells. Long-term exposure to GW4064 decreased the colony formation of RT4 and T24 cells. The wound healing migration assay revealed an inhibitory effect of GW4064 on both of these bladder cancer cell lines. In addition, integrin ß3 expression and myosin light chain phosphorylation were decreased after GW4064 treatment. Immunocytochemistry showed an increase in E-cadherin and a decrease in ß-catenin in the cell membrane of bladder cancer cells. Total protein expression and membrane fractionation assays also indicated upregulation of E-cadherin and downregulation of ß-catenin. Moreover, GW4064 reduced the invasion of muscle-invasive T24 cells. The GW4064-decreased migration and invasion were reversed by the proteasome inhibitor MG132 and the lysosome inhibitor NH4Cl. Furthermore, the GW4064-induced inhibition of matrix metalloproteinase-2 (MMP2) and cathepsin B expression was reversed by NH4Cl. Xenograft animal studies revealed that GW4064 declined MMP2, cathepsin B and lung metastasis of bladder cancer. In conclusion, GW4064 decreases the migration and invasion of human bladder cancer cells, which may provide a new therapeutic strategy for the treatment of human bladder cancer.