Project description:Renal cell carcinoma is particularly sensitive to ferroptosis, an iron-dependent non-apoptotic form of cell death. This mechanism does not require activation of caspase or the participation of other apoptotic effector molecules (such as BAX or BAK), nor is it accompanied by the morphological characteristics or biochemical processes of apoptosis. The STEAP3 gene was found because it promotes tumor apoptosis in prostate cancer, but its role in renal cell carcinoma has not been studied in depth. Through real-time quantitative polymerase chain reaction, we found that the expression of the STEAP3 gene was upregulated in renal cell carcinoma tissue samples and cell lines, and it was found to be highly expressed in renal cell carcinoma tissue through immunohistochemistry. This upregulation is related to poor survival and prognosis of patients. We used erastin, a ferroptosis inducer, found that renal cell carcinoma became more susceptible to ferroptosis after knocking down STEAP3. The results indicate that renal cell carcinoma cell lines with knocked down STEAP3 expression are more sensitive to ferroptosis, and this effect occurs through the p53/xCT pathway. In summary, our research helps to identify new biomarkers and provides new targets for the treatment of renal cell carcinoma.
Project description:Compelling evidences have revealed the emerging role of ferroptosis in the pathophysiological process of acute lung injury (ALI), but its modulation is not clear. Here, we identified that STAT6 acted as a critical regulator of epithelium ferroptosis during ALI. Firstly, STAT6 expression and activity were increased in the ALI mice models caused by crystalline silica (CS), LPS and X-ray exposure. Followed by confirming the contribution of ferroptosis in the above ALI with ferrostatin-1 and deferoxamine intervention, bioinformatic analyses revealed that STAT6 expression was negatively correlated with ferroptosis. Consistently, lung epithelium-specific depletion of STAT6 in mice or STAT6 knockdown in cultured epithelial cells exacerbated ferroptosis in the above ALI. While overexpression of STAT6 in lung epithelial cells attenuated the ferroptosis. Mechanistically, SLC7A11 is a typical ferroptosis-related gene and negatively regulated by P53. CREB-binding protein (CBP) is a critical acetyltransferase of P53 acetylation, showing valuable regulation on targets' transcription. Herein, we found that STAT6 negatively regulates ferroptosis through competitively binding with CBP, which inhibits P53 acetylation and transcriptionally restores SLC7A11 expression. Finally, pulmonary-specific STAT6 overexpression decreased the ferroptosis and attenuated CS and LPS induced lung injury. Our findings revealed that STAT6 is a pivotal regulator of ferroptosis, which may be a potential therapeutic target for the treatment of acute lung injury.
Project description:BackgroundHuman hydroxysteroid dehydrogenase-like 2 (HSDL2), which regulates cancer progression, is involved in lipid metabolism. However, the role of HSDL2 in cholangiocarcinoma (CCA) and the mechanism by which it regulates CCA progression by modulating ferroptosis are unclear.MethodsHSDL2 expression levels in CCA cells and tissues were determined by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry. The overall survival and disease-free survival of patients with high vs. low HSDL2 expression were evaluated using Kaplan-Meier curves. The proliferation, migration, and invasion of CCA cells were assessed using Cell Counting Kit-8, colony formation, 5-ethynyl-2'-deoxyuridine DNA synthesis, and transwell assays. The effect of p53 on tumor growth was explored using a xenograft mouse model. The expression of SLC7A11 in patients with CCA was analyzed using immunofluorescence. Ferroptosis levels were measured by flow cytometry, malondialdehyde assay, and glutathione assay. HSDL2-regulated signaling pathways were analyzed by transcriptome sequencing. The correlation between p53 and SLC7A11 was assessed using bioinformatics and luciferase reporter assays.ResultsHSDL2 expression was lower in primary human CCA tissues than in matched adjacent non-tumorous bile duct tissues. HSDL2 downregulation was a significant risk factor for shorter overall survival and disease-free survival in patients with CCA. In addition, HSDL2 knockdown enhanced the proliferation, migration, and invasion of CCA cells. The transcriptome analysis of HSDL2 knockdown cells showed that differentially expressed genes were significantly enriched in the p53 signaling pathway, and HSDL2 downregulation increased SLC7A11 levels. These findings were consistent with the qRT-PCR and western blotting results. Other experiments showed that p53 expression modulated the effect of HSDL2 on CCA proliferation in vivo and in vitro and that p53 bound to the SLC7A11 promoter to inhibit ferroptosis.ConclusionsHSDL2 knockdown promotes CCA progression by inhibiting ferroptosis through the p53/SLC7A11 axis. Thus, HSDL2 is a potential prognostic marker and therapeutic target for CCA.
Project description:This study aimed to explore the role of the creatine kinase B (CKB) gene in the development of human osteosarcoma (OS). Western blotting and qRT-PCR were performed to detect CKB expression in tissues and cells. CCK-8, colony formation, flow cytometry, Transwell, and cell scratch assays were performed to detect OS cell viability, proliferation, apoptosis, invasion, and migration. Gene set enrichment analysis (GSEA) was used to conduct signal pathway enrichment. CKB expression was higher in OS tissues and cells than that in normal tissues and cells. Silencing CKB expression reduced cell proliferation, migration, and invasion, and improved cell apoptosis in HOS cells, while overexpressing CKB increased cell proliferation, migration, and invasion, and decreased apoptosis in U2-OS cells. GSEA showed that CKB affected the p53 signaling pathway. Overexpression of CKB inhibited the protein expression of p53, p21, and Bax and promoted the expression of Bcl-2 and MDM2 in U2-OS cells. Conversely, silencing CKB promoted the protein expression of p53, p21, and Bax, and inhibited the expression of Bcl-2 and MDM2 in HOS cells. Silencing p53 could reverse the effect of the silencing CKB in HOS cells, and overexpressing p53 could reverse the effect of overexpressing CKB in U2-OS cells. Taken together, CKB affects the development of OS by regulating the activity of the p53 signaling pathway.
Project description:AimOvarian cancer (OC) is the most lethal gynecological malignancy, which seriously affects the prognosis and life quality of female patients. Therefore, new therapeutic targets and treatments are urgently needed.MethodsExpression levels of miR-93-5p and SLC7A11 and ferroptosis status in paracancerous and tumor tissues were examined and compared. The effect of the miR-93-5p-SLC7A11 regulatory loop on the malignant phenotype as well as the ferroptosis phenotype of SKOV3 cells was assessed. Furthermore, the interaction between miR-93-5p and SLC7A11 was confirmed via rescue experiment.ResultsIn this study, we found that miR-93-5p was lowly expressed in cancer tissues, and suggested that overexpression of miR-93-5p could target SLC7A11 to reduce its expression and promote ferroptosis, thereby inhibiting the malignant biological behaviors such as proliferation, invasion and migration, while knockdown of miR-93-5p restrained ferroptosis and promoting tumor growth. Besides, erastin, as a specific inhibitor of SLC7A11, could target down the expression of SLC7A11, induce the occurrence of ferroptosis, and reverse the effect of knockdown of miR-93-5p.ConclusionsTaken together, our findings disclosed that miR-93-5p increased the level of ferroptosis and inhibited the progression of OC by targeting and inhibiting the expression level of SLC7A11, which was a potential treatment in OC.
Project description:Methytransferase-like proteins 9 (METTL9) has been characterized as an oncogene in several cancers, however, its role in hepatocellular carcinoma (HCC) remains unknown. Here, we investigated the function and molecular mechanism of METTL9 in HCC. We showed that METTL9 expression was elevated in HCC, and its high expression was associated with poor survival outcomes. Knockdown of METTL9 observed a significant inhibition of HCC cell viability, migration, and invasion both in vitro and in vivo. By contrast, METTL9 overexpression HCC cells obtained stronger abilities in cell proliferation and migration. Mechanistically, we discovered that METTL9 knockdown led to a reduction in the expression level of SLC7A11, a key suppressor of ferroptosis, in turn, promoted ferroptosis in HCC cells, impeding the progression of HCC. Moreover, we have proved that targeting METTL9 could significantly restrain the growth of HCC patient-derived xenograft (PDX). Our study established METTL9 as a critical role in promoting HCC development and provides a foundation for further investigation and potential therapeutic interventions targeting ferroptosis in HCC.
Project description:Ferroptosis is a new form of regulated cell death, which is mediated by intracellular iron. Although it is reported that bavachin has antitumour effects on several tumour cells and prompts the reactive oxygen species (ROS) generation, it is unclear whether ferroptosis can be induced by bavachin in osteosarcoma (OS) cells. In this study, we found that bavachin inhibits the viability of MG63 and HOS OS cell lines along with an increase in the ferrous iron level, ROS accumulation, malondialdehyde overexpression, and glutathione depletion. Moreover, iron chelators (deferoxamine), antioxidants (Vit E), and ferroptosis inhibitors (ferrostatin-1 and liproxstatin-1) reverse bavachin-induced cell death. Bavachin also altered the mitochondrial morphology of OS cells, leading to smaller mitochondria, higher density of the mitochondrial membrane, and reduced mitochondrial cristae. Further investigation showed that bavachin upregulated the expression of transferrin receptor, divalent metal transporter-1, and P53, along with downregulating the expression of ferritin light chain, ferritin heavy chain, p-STAT3 (705), SLC7A11, and glutathione peroxidase-4 in OS cells. More importantly, STAT3 overexpression, SLC7A11 overexpression, and pretreatment with pifithrin-α (P53 inhibitor) rescued OS cell ferroptosis induced by bavachin. The results show that bavachin induces ferroptosis via the STAT3/P53/SLC7A11 axis in OS cells.
Project description:BackgroundOvarian cancer (OC) has high mortality and poor prognosis for lacking of specific biomarkers and typical clinical symptoms in the early stage. CEBPG is an important regulator in tumor development, yet it is unclear exactly how it contributes to the progression of OC.MethodsTCGA and tissue microarrays with immunohistochemical staining (IHC) were used to examine CEBPG expression in OC. A variety of in vitro assays were conducted, including colony formation, proliferation, migration, and invasion. The orthotopic OC mouse model was established for in vivo studies. Ferroptosis was detected by observing mitochondrial changes with electron microscopy, detecting ROS expression, and detecting cell sensitivity to drugs by CCK8 assay. The interaction between CEBPG and SLC7A11 was confirmed by CUT&Tag and dual luciferase reporter assays.ResultsA significantly higher expression level of CEBPG in OC when compared with benign tissues of ovary, and that high CEBPG expression level was also tightly associated with poor prognosis of patients diagnosed with OC, as determined by analysis of datasets and patient samples. Conversely, knockdown of CEBPG inhibited OC progression using experiments of OC cell lines and in vivo orthotopic OC-bearing mouse model. Importantly, CEBPG was identified as a new participator mediating ferroptosis evasion in OC cells using RNA-sequencing, which could contribute to OC progression. The CUT&Tag and dua luciferase reporter assays further revealed the inner mechanism that CEBPG regulated OC cell ferroptosis through transcriptional control of SLC7A11.ConclusionsOur findings established CEBPG as a novel transcriptional regulator of OC ferroptosis, with potential value in predicting clinical outcomes and as a therapeutic candidate.
Project description:AbstractThe molecular mechanism for nobiletin's protective effect against heatstroke-induced acute lung injury (HS-ALI) remains largely unknown. Previous research has demonstrated that ferroptosis is an important pathogenic event in HS-ALI. Nobiletin is a natural polymethoxylated flavonoid. Herein, we investigated the potential contribution of nobiletin to HS-ALI by inhibiting ferroptosis. Heat stress was used to induce HS-ALI in mice, and mouse lung epithelial-12 (MLE-12) cells were stimulated by heat stress in vitro . Nobiletin was administrated by gavage for 2 h before HS induction. Biochemical kits, immunofluorescence staining, and western blotting were performed on the markers of ferroptosis. Our results showed that nobiletin administration significantly attenuated HS-induced lung injury and ferroptosis. Moreover, nobiletin pretreatment significantly reversed HS-induced p53 upregulation in vivo and in vitro . Pretreatment with a p53 agonist, tenovin-6, partly abolished the protective effect of nobiletin in mice with HS-ALI. Meanwhile, p53 knockdown significantly increased GPX4 and SLC7A11 expression levels compared with the HS group in HS-induced MLE-12 cells. Subsequently, nobiletin ameliorated HS-induced MLE-12 cells ferroptosis by activating the SLC7A11/GPX4 pathway, whereas p53 overexpression effectively abolished the protective effect of nobiletin. Taken together, our findings reveal that nobiletin attenuates HS-ALI by inhibiting ferroptosis through the p53/SLC7A11 pathway, indicating it to be a potential therapeutic agent for HS-ALI prevention and treatment.