Project description:Studies have indicated that RAB17 expression levels are associated with tumor malignancy, and RAB17 is more highly expressed in endometrial cancer (EC) tissues than in peritumoral tissues. However, the roles and potential mechanisms of RAB17 in EC remain undefined. The present study confirmed that the expression of RAB17 facilitates EC progression by suppressing cellular ferroptosis-like alterations. Mechanistically, RAB17 attenuated ferroptosis in EC cells by inhibiting transferrin receptor (TFRC) protein expression in a ubiquitin proteasome-dependent manner. Because EC is a blood-deprived tumor with a poor energy supply, the relationship between RAB17 and hypoglycemia was investigated. RAB17 expression was increased in EC cells incubated in low-glucose medium. Moreover, low-glucose medium limited EC cell ferroptosis and promoted EC progression through the RAB17-TFRC axis. The in vitro results were corroborated by in vivo studies and clinical data. Overall, the present study revealed that increased RAB17 promotes the survival of EC cells during glucose deprivation by inhibiting the onset of TFRC-dependent ferroptosis.
Project description:Backgroundα-Crystallin B (CRYAB) is a chaperone member of the HSPs family that protects proteins with which it interacts from degradation. This study aims to investigate the effect of CRYAB on the progression of colorectal cancer (CRC) and its underlying mechanism.MethodsCRYAB expression was evaluated in CRC tissues. Cell growth was tested by CCK-8 kit. Lipid reactive oxygen species (ROS) assays, lipid peroxidation assays, glutathione assays were used to assess the degree of cellular lipid peroxidation of CRC cells. The potential signal pathways of CRYAB were analyzed and verified by Western blot (WB) and immunoprecipitation (Co-IP).ResultsCRYAB expression was elevated in CRC tissues and exhibited sensitivity and specificity in predicting CRC. Functionally, knockdown of CRYAB induced ferroptosis in CRC cells. Mechanistically, CRYAB binding prevented from β-catenin interacting with TRIM55, leading to an increase in β-catenin protein stability, which desensitized CRC cells to ferroptosis and ultimately accelerated cancer progression.ConclusionsTargeting CRYAB might be a promising strategy to enhance ferroptosis and improve the efficacy of CRC therapy.
Project description:Cytochrome P450 F3 (CYP4F3) is recognized as a disease-associated immune response initiator that is involved in the synthesis of cholesterol, steroids, and lipids. This study identified the upregulation of CYP4F3 expression in colorectal cancer (CRC) and its association with poor patient prognosis through a comparative analysis between CRC tumor tissues with normal tissues from public databases. The overexpression of CYP4F3 in CT26.wt and SW620, promoted cell proliferation and migration, a reduction of cellular oxidative stress, an up-regulation of the oxidative stress-related pathway NRF2, and an inhibition of cellular ferroptosis. Additionally, inhibition of NRF2 activity stimulated cellular ferroptosis when CYP4F3 was overexpressed. Ferroptosis, characterized by iron-dependent lipid peroxidation, is a non-apoptotic way of cell death with a critical role in cancer development. When given a ferroptosis agonist to CYP4F3-overexpression CRC cells, NRF2 was activated, and cell proliferation and migration were reduced. Furthermore, the mice subcutaneously injected with CYP4F3-overexpression CT26.wt cells formed significantly larger tumors compared to the CYP4F3-vector CT26.wt cell group. This study systematically identified an important role of CYP4F3 in CRC development as a regulator of CRC cells to escape ferroptosis via NRF2, highlighting the significance of CYP4F3 as a potential therapeutic target for CRC.
Project description:Background: Bladder cancer (BCa) is a prevalent urologic malignancy that shows a poor prognosis. Abnormal metabolism and its key genes play a critical role in BCa progression. In this study, the role played by PhosphoGlycerol Dehydrogenase (PHGDH), an important molecule of serine metabolism, was investigated with regard to the regulation of ferroptosis in BCa. Methods: The BCa tissues of 90 patients were analyzed by RNA-sequencing for differential pathways and genes. Western blot, qPCR, and IHC were used to determine PHGDH expression in the cell lines (in vitro) and patient tissues (in vivo). R software was used to analyze PHGDH expression, prognosis, and PHGDH+SLC7A11 score. The biological functions of PHGDH were examined through organoids, and in vitro and in vivo experiments. C11 probes, electron microscopy, and ferroptosis inhibitors/ inducers were used to detect cellular ferroptosis levels. Protein profiling, co-IP, and RIP assays were used to screen proteins that might bind to PHGDH. PHGDH-targeted inhibitor NCT-502 was used to evaluate its effect on BCa cells. Results: PHGDH was highly expressed in patients with BCa. Knock-down of PHGDH promoted ferroptosis, while the decreased proliferation of BCa cells. Additionally, PHGDH knock-down downregulated the expression of SLC7A11. Co-IP and mass spectrometry experiments indicate that PHGDH binds to PCBP2, an RNA-binding protein, and inhibits its ubiquitination degradation. PCBP2 in turn stabilizes SLC7A11 mRNA and increases its expression. NCT-502, a PHGDH inhibitor, promotes ferroptosis and inhibits tumor progression in BCa. The PHGDH+ SLC7A11 score was significantly correlated with patient prognosis. Conclusions: To conclude, the PHGDH, via interaction with PCBP2, upregulates SLC7A11 expression. This inhibits ferroptosis and promotes the malignant progression of BCA. The results of this study indicated that NCT-502 could serve as a therapeutic strategy for BCa.
Project description:Purpose:To investigate the function of circ_0005576 in colorectal cancer (CRC) progression. Patients and Methods:Circ_0005576 expression in CRC patients was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and in situ hybridization (ISH). CRC cells were transfected using Lipofectamine 2000 reagent. CRC cell proliferation was researched by Cell Counting Kit-8 (CCK-8) assay and 5-ethynyl-2-deoxy-uridine (EdU) incorporation experiment. Cell cycle and apoptosis were determined by flow cytometry analysis. Luciferase reporter assay was used to explore the relationship between circ_0005576 and miR-874 or between miR-874 and CDK8. qRT-PCR and Western blot were used to detect circ_0005576, miR-874, and CDK8 expression. In vivo experiments were performed using nude mice. CDK8 and Ki67 expression in xenograft tumors was investigated by immunohistochemistry. Tunel assay was conducted to analyze the apoptosis of xenograft tumors. Results:Circ_0005576 expression was up-regulated in CRC, which was associated with tumor progression (P < 0.05 or P < 0.01). Circ_0005576 knockdown in CRC cells reduced proliferation, induced apoptosis, increased cells in the G1 phase, and decreased cells in the S phase (P < 0.01 or P < 0.001). Circ_0005576 promoted CDK8 expression via sponging miR-874. miR-874 knockdown and CDK8 overexpression significantly reversed the inhibitory effect of circ_0005576 knockdown on CRC cells malignant phenotype (P < 0.05 or P < 0.01). Circ_0005576 knockdown inhibited tumor growth in vivo (P < 0.01). Circ_0005576 knockdown reduced CDK8, Ki67 expression, and enhanced apoptosis in xenograft tumors. Conclusion:Circ_0005576 promoted malignant progression through the miR-874/CDK8 axis in CRC.
Project description:BackgroundmiR-196b-5p expression is deregulated in many malignant tumors. Although miR-196b-5p has been implicated in the malignant transformation of colorectal cancer, its role in this specific type of cancer has not been fully explored. Thus, the present study was aimed to examine the cellular function of miR-196b-5p and its role in malignant biological behavior in colorectal cancer.MethodsmiR-196b-5p expression was measured in colorectal cancer tissues and cell lines using quantitative real-time PCR. Cell counting kit-8 (CCK-8) assay and Transwell assay were used to detect proliferation, migration, and invasion in cell lines, whereas flow cytometry was applied to study apoptosis. Western blot analysis was performed to measure the protein levels. Dual luciferase reporter assay was used to investigate the interaction between miR-196b-5p and ING5. Tumor formation was evaluated in mice.ResultsMiR-196b-5p was abundantly expressed in colorectal cancer tissues and cell lines, whereas ING5 was expressed at low levels. MiR-196b-5p was successfully overexpressed or knocked down in colorectal cancer cells. We found that miR-196b-5p overexpression significantly accelerated the proliferation, cell cycle, migration and invasion, while inhibited cell apoptosis in colorectal cancer cells. However, miR-196b-5p inhibitor showed the opposite effects. Moreover, ING5 overexpression or knockdown was successfully performed in colorectal cancer cells. ING5 overexpression suppressed proliferation, migration, invasion, the phosphorylation of PI3K, Akt as well as MEK, and promoted cell apoptosis, which could be reversed by ING5 knockdown. Additionally, ING5 was identified as a target of miR-196b-5p through bioinformatics analysis and a luciferase activity assay. Furthermore, ING5 knockdown could attenuate the decrease in proliferation, migration, invasion, and the protein levels of p-PI3K, p-Akt, and p-MEK, which were induced by miRNA-196b-5p inhibitor. Besides, miR-196b-5p knockdown inhibited tumor growth, whereas ING5 knockdown elevated it in vivo.ConclusionsIn conclusion, miR-196b-5p promotes cell proliferation, migration, invasion, and inhibits apoptosis in colorectal cancer by targeting ING5.
Project description:BackgroundHead and neck squamous cell carcinoma (HNSCC) is an aggressive disease worldwide. Much progress has been made in exploring mechanisms and improving the therapy of HNSCC, but only a few studies have focused on the role of ferroptosis on HNSCC progression. The current study aimed to reveal the underlining mechanisms that caveolin-1 (CAV1)-ROS (reactive oxygen species)-ferroptosis axis affect the process of HNSCC and discover novo therapeutic targets or strategies.MethodsThe role of CAV1 in ferroptosis was analyzed by FerrDb, and its clinical significance was examined by TCGA dataset of HNSCC. The expressions of caveolin-1 (CAV1) in HNSCC tissues were measured by immunohistochemistry, western blot, and real-time PCR assay. Three siRNA sequences were designed to silence CAV1 mRNA in HNSCC cells. Cell proliferation, colony formation, wound-healing, and transwell assays were used to examine the proliferation, migration, and invasion of cancer cells. ROS evaluation and intracellular Fe2+ content assays were performed to examine the levels of ferroptosis.ResultsThrough the analysis with published data, CAV1 was found to overexpress in HNSCC than normal tissues, and was one of the vital suppressors of ferroptosis pathway. Our study showed that CAV1 was over expressed in HNSCC tissues and the high level of CAV1 predicted poorer prognosis. Further experiments indicated that CAV1 could inhibit the ferroptosis of cancer cells and promote the proliferation, migration and invasion.ConclusionsOverexpression of CAV1 in HNSCC inhibited the process of ferroptosis, leading to aggressive phenotypes, as well as worse prognosis. The regulatory pathway of CAV1 and ferroptosis are potential targets for designing diagnostic and combined therapeutic strategies for HNSCC patients.
Project description:BackgroundGlioblastoma (GBM) is a brain tumor characterized by the highest malignancy and the poorest prognoses. RNA binding motif single strand interacting protein 1 (RBMS1) has been implicated to be involved in various cancer progression. This study was conceived to explore the role and the mechanism of RBMS1 in GBM.MaterialsRT-qPCR and western blot were used to evaluate RBMS1 expression and examine the transfection efficiency of sh-RBMS1. Cell proliferation was detected using CCK-8 assay and colony formation assay while cell apoptosis was detected with flow cytometry. Cell migration and invasion were detected with wound healing and transwell assay. The activities of MMP2 and MMP9 were detected using gelatin zymography. Western blot was used to measure proliferation-, apoptosis-, ferroptosis- and EMT-related proteins. Lipid peroxidation was detected with TBARS Assay Kit and lipid ROS was detected with a BODIPY 581/591 C11 kit. The total iron level was detected using corresponding assay kits.ResultsAccording to GEPIA database, RBMS1 expression was upregulated in GBM and the present study found that RBMS1 expression was upregulated in GBM cells. After interfering RBMS1, GBM cell proliferation, migration, invasion and EMT process were inhibited while cell apoptosis and ferroptosis were promoted. However, ferroptosis inhibitor Fer-1 partially counteracted the protective effects of RBMS1 knockdown on GBM.ConclusionCollectively, this study revealed that RBMS1 silence inhibited the malignant progression of GBM possibly through ferroptosis.
Project description:BackgroundLOX-like 1 (LOXL1) is a lysyl oxidase, and emerging evidence has revealed its effect on malignant cancer progression. However, its role in colorectal cancer (CRC) and the underlying molecular mechanisms have not yet been elucidated.MethodsLOXL1 expression in colorectal cancer was detected by immunohistochemistry, western blotting and real-time PCR. In vitro, colony formation, wound healing, migration and invasion assays were performed to investigate the effects of LOXL1 on cell proliferation, migration and invasion. In vivo, metastasis models and mouse xenografts were used to assess tumorigenicity and metastasis ability. Molecular biology experiments were utilized to reveal the underlying mechanisms by which LOXL1 modulates the Hippo pathway.ResultsLOXL1 was highly expressed in normal colon tissues compared with cancer tissues. In vitro, silencing LOXL1 in CRC cell lines dramatically enhanced migration, invasion, and colony formation, while overexpression of LOXL1 exerted the opposite effects. The results of the in vivo experiments demonstrated that the overexpression of LOXL1 in CRC cell lines drastically inhibited metastatic progression and tumour growth. Mechanistically, LOXL1 inhibited the transcriptional activity of Yes-associated protein (YAP) by interacting with MST1/2 and increasing the phosphorylation of MST1/2.ConclusionsLOXL1 may function as an important tumour suppressor in regulating tumour growth, invasion and metastasis via negative regulation of YAP activity. Video abstract.
Project description:BackgroundColorectal cancer (CRC) is a prevalent malignancy of the gastrointestinal. Circular RNAs (circRNAs) act as important roles in CRC malignant progression. However, the role of circ_0039857 in CRC is still unclear. Therefore, this study aimed to explore the function and mechanism of hsa_circ_0039857 in the CRC.MethodsThe mRNA and protein expression were measured via RT-qPCR. RNase R assay and Actinomycin D were employed to evaluate the stability of circ_0039857. Functional experiments, such as proliferation and apoptosis, were applied to study the function of circ_0039857 in CRC cells. The underlying mechanisms of circ_0039857 were then analyzed by bioinformatics, dual-luciferase reporter gene assay, RNA pull-down and rescue experiments.ResultsWe revealed that circ_0039857 was significantly enhanced in CRC. Circ_0039857 was stabler than linear RNA in cells and valuable for the disease diagnosis. In addition, circ_0039857 knockdown inhibited proliferation and promoted apoptosis. Mechanistically, circ_0039857 positively regulated the expression of RAB32 via sponging miR-338-3p.ConclusionThis study demonstrated that circ_0039857 knockdown suppressed CRC malignant progression through miR-338-3p/RAB32 axis. Most importantly, this will help us to better understand the circRNA network in CRC, and may find potential biomarkers and targets for CRC clinical treatment.