WITHDRAWN: Low-Intensity Pulsed Ultrasound-Generated Singlet Oxygen Induces Telomere Damage Leading to Glioma Stem Cell Awakening From Quiescence

Abstract

Background: Cancer stem cells, quiescent and drug-resistant, have become a therapeutic target. Low-intensity pulsed ultrasound (LIPUS), a new noninvasive physical device, promotes pluripotent stem cell differentiation and is mainly applied in tissue engineering but rarely in oncotherapy. We explored the effect and mechanism of LIPUS on glioma stem cell (GSC) expulsion from quiescence.Methods: Immunofluorescence staining and flow cytometry were used to detect changes of stem hallmarkers. RT-PCR results showed the gene expression levels of stem-related transcription factors. Brud and RNA-seq were performed for cell cycle analysis. Western blotting showed different expressions of key point proteins. Telomeres damage was found by FISH and IF-FISH. Fluorescence detection was used for mitochondrial membrane potential assay and singlet oxygen detection. Tumor xenograft and immunohistochemical staining were performed to confirm the role of low intensity pulsed ultrasound.Results: We found that LIPUS led to attenuated expression of GSC hallmarks, promoted GSC escape from G0 quiescence, and significantly weakened the stemness-related Wnt and Hh pathways. Next, Interestingly, LIPUS transferred sonomechanical energy into recombinant cytochrome C and B5 proteins in vitro, which converted oxygen molecules into singlet oxygen, triggering a telomere crisis. The results in vivo and in vitro confirmed that LIPUS enhanced GSC sensitivity to temozolomide.Conclusion: These results demonstrated that LIPUS “wakes up” GSCs to improve chemotherapy by transferring energy to cyt families and leading to telomere crisis.