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Abstract Background The failure of novel therapies effective in preclinical animal models largely reflects the fact that current models do not really mimic the pathological/therapeutic features of glioblastoma (GBM), in which the most effective temozolomide chemoradiotherapy (RT/TMZ) regimen can only slightly extend survival. How to improve RT/TMZ efficacy remains a major challenge in clinic. Methods Syngeneic G422TN-GBM model mice were subject to RT/TMZ, surgery, piperlongumine (PL), αPD1, glutathione. Metabolomics or transcriptomics data from G422TN-GBM and human GBM were used for gene enrichment analysis and estimation of ROS generation/scavenging balance, oxidative stress damage, inflammation and immune cell infiltration. Overall survival, bioluminescent imaging, immunohistochemistry, and immunofluorescence staining were used to examine therapeutic efficacy and mechanisms of action. Results Here we identified that glutathione metabolism was most significantly altered in metabolomics analysis upon RT/TMZ therapies in a truly refractory and reliable mouse triple-negative GBM (G422TN) preclinical model. Consistently, ROS generators/scavengers were highly dysregulated in both G422TN-tumor and human GBM. The ROS-inducer PL synergized surgery/TMZ, surgery/RT/TMZ or RT/TMZ to achieve long-term survival (LTS) in G422TN-mice, but only one LTS-mouse from RT/TMZ/PL therapy passed the rechallenging phase (immune cure). Furthermore, the immunotherapy of RT/TMZ/PL plus anti-PD-1 antibody (αPD1) doubled LTS (50%) and immune-cured (25%) mice. Glutathione completely abolished PL-synergistic effects. Mechanistically, ROS reduction was associated with RT/TMZ-resistance. PL restored ROS level (mainly via reversing Duox2/Gpx2), activated oxidative stress/inflammation/immune responses signature genes, reduced cancer cell proliferation/invasion, increased apoptosis and CD3+/CD4+/CD8+ T-lymphocytes in G422TN-tumor on the basis of RT/TMZ regimen. Conclusion Our findings demonstrate that PL reverses RT/TMZ-reduced ROS and synergistically resets tumor microenvironment to cure GBM. RT/TMZ/PL or RT/TMZ/PL/αPD1 exacts effective immune cure in refractory GBM, deserving a priority for clinical trials.

Objective To explore the influence of calcium channel blocker(CCB), verapamil, on steroid hormone profile of primary cultured aldosterone producing adenoma(APA)cells. Methods The adrenal tumor tissues of 6 APA patients with hypokalemia operated in Peking Union Medical College Hospital were cultured and treated with different concentrations of verapamil. The steroid hormone profile was detected by liquid chromatography-tandem mass spectrometry(LC-MS/MS). Results The level of aldosterone in 50 μmol/L verapamil group was lower than that in 10 μmol/L verapamil group and control group(P＜0.01). The levels of aldosterone precursor, 11-deoxycorticosterone in verapamil 10 μmol/L group was lower than that in control group (P＜0.05). The levels of 18-oxocortisol(18-OXOF) and 18-hydroxycortisol(18-OHF) in verapamil 50 μmol/L group and verapamil 10 μmol/L group were lower than that in the control group (P＜0.05). In addition, verapamil also had some inhibitory effects on glucocorticoids such as cortisol and cortisone, and adrenal derived sex hormones such as dehydroepiandrosterone sulfate(DHEA-S) and 11 beta-hydroxytestosterone(11β-OHT). Conclusions In addition to inhibit-ing aldosterone secretion in primary cultured APA cells, CCB has significant inhibitory effects on a variety of other steroid hormones, such as precursor 11-deoxycorticosterone, cortisol, metabolites, 18-OXOF and 18-OHF.