Silencing HEATR1 Rescues Cisplatin Resistance of Non-Small Cell Lung Cancer by Inducing Ferroptosis via the p53/SAT1/ALOX15 Axis.

BACKGROUND: Cisplatin (DDP) is a commonly used chemotherapy agent. However, its resistance to the drug is a major challenge in its clinical application. Earlier research has suggested a connection between HEATR1 and chemoresistance in cancer. However, additional investigation is needed to better understand its involvement in resistance to DDP. In this study, we aimed to determine the regulatory effect of HEATR1 on the resistance of cisplatin in NSCLC. METHODS: We collected specimens of both DDP-resistant and non-resistant NSCLC to examine the expression of HEATR1. Additionally, we established cisplatin-resistant cells of NSCLC using the A549 cell line. Cell ability was examined by CCK-8 assay. Cell apoptosis and lipid ROS were examined by flow cytometry. The expressions of HEATR1, p53, SAT1, and ALOX15 were determined by qRT-PCR and Western blot. The tumor xenograft experiment was conducted to assess the impact of silencing HEATR1 on cisplatin resistance in vivo in NSCLC. RESULTS: The expression levels of HEATR1 were found to be significantly elevated in DDP-resistant tissues and cells of NSCLC as compared to non-resistant counterparts. Conversely, the expression levels of p53, SAT1, and ALOX15 were observed to be reduced in DDP-resistant cells. Through the inhibition of HEATR1, the proliferation of DDP-resistant cells was significantly suppressed, while the generation of lipid ROS was enhanced. This effect was achieved by activating ferroptosis and the p53/SAT1/ALOX15 pathway, as demonstrated both in vitro and in vivo. Conversely, the overexpression of HEATR1 exhibited opposite effects. Furthermore, the silencing of p53 and ALOX15 reversed the oncogenic effects of HEATR1 and inhibited ferroptosis in DDP-resistant NSCLC cells, suggesting the involvement of p53 and ALOX15 in HEATR1-mediated DDP resistance. CONCLUSION: Finally, the findings revealed that HEATR1 silencing reduced DDP resistance in NSCLC by inducing ferroptosis via the p53/SAT1/ALOX15 axis. HEATR1 might become a potential target for overcoming DDP resistance in NSCLC treatment.

Metabolomic analysis identifies the regulation of lipid metabolism pathway as potential mechanisms of Jiangzhi decoction against non-alcoholic fatty liver disease.

OBJECTIVES: To illustrate the metabolic regulatory mechanisms of Jiangzhi decoction (JZD) against non-alcoholic fatty liver disease (NAFLD). METHODS: High-fat diet (HFD)-induced NAFLD rats were treated with JZD. The pathological morphology, lipid indexes and liver function were detected. Metabolic profiles were examined by liquid chromatography-mass spectrometry (LC-MS). Multivariate and univariate statistical analysis were used to search the differential metabolites. Pathway enrichment analysis was carried out using Kyoto Encyclopedia of Genes and Genomes database. Compound-gene networks were built by Cytoscape software. RESULTS: JZD significantly alleviated the pathological conditions and improved lipid index levels. Multivariate analysis showed a good separation among different groups. Three hundred and twenty-seven metabolites in HFD versus control and 301 metabolites in JZD versus HFD were identified to be significantly different. Pathway enrichment analysis showed that lipid metabolism pathways were prominent altered pathways. Importantly, the relationships were more distant between JZD and HFD groups in all five lipid metabolism pathways, including arachidonic acid metabolism, linoleic acid metabolism, biosynthesis of unsaturated fatty acids, glycerophospholipid metabolism and sphingolipid metabolism, while those were obviously closer between JZD and control groups. Simultaneously, JZD treatment restored the levels of disturbed differential metabolites in HFD group. CONCLUSION: JZD had an effect on alleviating NAFLD via regulating relevant lipid metabolism.

lncRNA miR4458HG modulates hepatocellular carcinoma progression by activating m6A-dependent glycolysis and promoting the polarization of tumor-associated macrophages.

Long non-coding RNAs (lncRNAs) play significant roles in different biological functions of cancers. However, their function in the metabolism of glucose in patients with human hepatocellular carcinoma (HCC) remains largely unknown. In this study, HCC and paired intact liver tissues were utilized to examine the miR4458HG expression using qRT-PCR and human HCC cell lines to examine cell proliferation, colony formation, and glycolysis after transfection of siRNAs targeting miR4458HG or miR4458HG vectors. The molecular mechanism of miR4458HG was clarified through in situ hybridization, Western blotting, qRT-PCR, RNA pull-down, and RNA immunoprecipitation analysis. The results showed that the miR4458HG affected HCC cell proliferation, activated the glycolysis pathway, and promoted the polarization of tumor-associated macrophage in vitro and in vivo models. Mechanistically, miR4458HG bound IGF2BP2 (a key RNA m6A reader) and facilitated IGF2BP2-mediated target mRNA stability, including HK2 and SLC2A1 (GLUT1), and consequently altered HCC glycolysis and tumor cell physiology. At the same time, HCC-derived miR4458HG could be wrapped in the exosomes and promoted the polarization of tumor-associated macrophage by increasing ARG1 expression. Hence, miR4458HG is oncogenic in nature among patients with HCC. To develop an effective treatment strategy of HCC patients presenting with high glucose metabolism, physicians should focus on miR4458HG and its pathway.

CHAC1 promotes cell ferroptosis and enhances radiation sensitivity in thyroid carcinoma.

ChaC glutathione-specific γ-glutamylcyclotransferase 1 (CHAC1) is involved in intracellular glutathione depletion, ferroptosis, and tumorigenesis. The functional role of CHAC1 expression in thyroid carcinoma has not yet been established. The present study aimed to investigate the impact and mechanisms of CHAC1 on ferroptosis and radiation sensitivity in thyroid carcinoma. CHAC1 expression was examined in tumor tissue specimens and microarrays and thyroid carcinoma cell lines. CHAC1 was silenced or overexpressed by lentivirus transfection in thyroid carcinoma cells. Cell viability and lipid ROS levels were evaluated by Cell Counting Kit-8 and flow cytometry, respectively. The effect of CHAC1 on tumor growth in vivo was also measured. Ferroptosis-related proteins were measured by western blotting. CHAC1 expression was decreased in patients with thyroid carcinoma, and overexpression of CHAC1 suppressed cell viability of BCPAP cells and tumor growth in xenografted nude mice. Exposure to Ferrostatin-1, a ferroptosis inhibitor, significantly attenuated the inhibitory effects of CHAC1 overexpression on cell viability. In CHAC1-overexpressing BCPAP cells, ferroptosis was induced as indicated by increased lipid ROS production and PTGS2 expression. Knocking down of CHAC1 in K1 cells significantly induced cell viability, reduced lipid ROS production and PTGS2 expression, and enhanced GPX4 expression. Such effects were attenuated by RSL3, a ferroptosis inducer. Furthermore, we showed that CHAC1 overexpression enhanced radiation sensitivity in BCPAP cells as indicated by decreased cell viability, while CHAC1 knockdown had reversed effects in K1 cells as indicated by increased cell viability. Taken together, CHAC1 overexpression promoted ferroptosis and enhanced radiation sensitivity in thyroid carcinoma.

Targeting UBR5 in hepatocellular carcinoma cells and precise treatment via echinacoside nanodelivery.

BACKGROUND: Hepatocellular carcinoma (HCC) is among the most common and malignant cancers with no effective therapeutic approaches. Echinacoside (ECH), a phenylethanoid glycoside isolated from Chinese herbal medicine, Cistanche salsa, can inhibit HCC progression; however, poor absorption and low bioavailability limit its biological applications. METHODS: To improve ECH sensitivity to HepG2 cells, we developed a mesoporous silica nanoparticle (MSN)-based drug delivery system to deliver ECH to HepG2 cells via galactose (GAL) and poly(ethylene glycol) diglycidyl ether (PEGDE) conjugation (ECH@Au@MSN-PEGDE-GAL, or ECH@AMPG). Gain- and loss-of-function assays were conducted to assess the effects of UBR5 on HCC cell apoptosis and glycolysis. Moreover, the interactions among intermediate products were also investigated to elucidate the mechanisms by which UBR5 functions. RESULTS: The present study showed that ubiquitin protein ligase E3 component N-recognin 5 (UBR5) acted as an oncogene in HCC tissues and that its expression was inhibited by ECH. AMPG showed a high drug loading property and a slow and sustained release pattern over time. Moreover, owing to the valid drug accumulation, ECH@AMPG promoted apoptosis and inhibited glycolysis of HepG2 cells in vitro. In vivo experiments demonstrated that AMPG also enhanced the antitumor effects of ECH in HepG2 cell-bearing mice. CONCLUSIONS: Our results indicated the clinical significance of UBR5 as a therapeutic target. On the basis of the nontoxic and high drug-loading capabilities of AMPG, ECH@AMPG presented better effects on HCC cells compared with free ECH, indicating its potential for the chemotherapy of HCC.

The role of PYCR1 in inhibiting 5-fluorouracil-induced ferroptosis and apoptosis through SLC25A10 in colorectal cancer.

Although PYCR1 is a well-recognized oncogenic gene for malignant tumors, the causal relationship of its expression with malignant growth and cytotoxic chemotherapeutics remains unclear. Therefore, this study aimed to clarify the role of PYCR1 and its interaction with SLC25A10 in a chemotherapeutic agent 5-fluorouracil (5-FU)'s toxicity to colorectal cancer cells. PYCR1 and SLC25A10 expressions were detected in The Cancer Genome Atlas database and colon adenocarcinoma (COAD) clinical samples. PYCR1 upregulation was associated with SLC25A10 expression and poor prognosis, and its high expression indicated decreased survival rates in patients with COAD. PYCR1 overexpression inhibited lipid reactive oxygen species production and promoted SLC25A10 expression in colorectal cancer cells. PYCR1 silencing enhanced the antitumor effects of 5-FU. Ferroptosis inhibitor deferoxamine suppressed the antitumor effects of PYCR1 silencing, whereas ferroptosis inducer erastin inhibited the protumor effects of PYCR1 overexpression. SLC25A10 overexpression reversed the antitumor effects of PYCR1 silencing in vitro and inhibited the antitumor effects of erastin in vivo. Therefore, PYCR1 is an oncogenic gene that promotes colorectal tumor growth and desensitizes colorectal cancer cells to 5-FU cytotoxicity by preventing apoptosis and ferroptosis.