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Qi, Z.-X.

Publications and source records attributed to Qi, Z.-X..

2 recordsLinked to original sources

The DDIT4L-TOM40-ATP5A pathway suppresses glioblastoma oncogenesis

The characteristics of glioblastoma (GBM), including resistance to cell death and aberrant energy metabolism, are associated with the function of mitochondria. To date, the inherent suppressors that couple mitochondrial function with cell death remain unclear. DNA damage-inducible transcript 4-like (DDIT4L) expression in human gliomas and its association with patient survival was determined by public databases, western-blot and immunostaining. The role of DDIT4L in regulating tumor growth was analyzed using lentivirus and PDX model. The mechanism of DDIT4L on GBM mitochondrial function was determined by different assays. Here, we show that DDIT4L is an endogenous inhibitor of GBM via suppressing mitochondrial function. DDIT4L was expressed at high levels in GBM and transported into mitochondria via single import channel TOM40 other than the import receptors TOM22, TOM20 or TOM70. Then, DDIT4L interacted with the subunit of ATP synthase, inhibited mitochondrial function and induced tumor cell apoptosis. Furthermore, the synthetic peptide DDIT4LV125-P132 suppressed GBM oncogenesis. Based on these results, DDIT4L suppresses GBM oncogenesis through both TOM40- and ATP5A-dependent mechanisms to curb mitochondrial dynamics and induce cell apoptosis, and the DDIT4LV125-P132 peptide is a potential therapy for GBM.

cancer biology↗

Physiological Significance of R-fMRI Indices in Detecting Structural Brain Lesions

Resting-state functional MRI (R-fMRI) research has recently entered the era of \"big data\", however, few studies have provided a rigorous validation of the physiological underpinnings of R-fMRI indices. Although studies have reported that various neuropsychiatric disorders exhibit abnormalities in R-fMRI measures, these \"biomarkers\" have not been validated in differentiating structural lesions (brain tumors) as a concept proof. We enrolled 60 patients with intracranial tumors located in the unilateral cranial cavity and 60 matched normal controls to test whether R-fMRI indices can differentiate tumors, which represents a prerequisite for adapting such indices as biomarkers for neuropsychiatric disorders. Common R-fMRI indices of tumors and their counterpart control regions, which were defined as the contralateral normal areas (for amplitude of low frequency fluctuations (ALFF), fractional ALFF (fALFF), regional homogeneity (ReHo) and degree centrality (DC)) and ipsilateral regions surrounding the tumors (for voxel-mirrored homotopic connectivity (VMHC)), were comprehensively assessed. According to paired t-tests with a Bonferroni correction, only ALFF (both with and without Z-standardization) and VMHC (Fishers r-to-z transformed) could successfully differentiate substantial tumors from their counterpart normal regions in patients. And DC was not able to differentiate tumor from normal unless employed Z-standardization. To validate the lower power in the between-subject design than in the within-subject design, each metric was calculated in a matched control group, and two-sample t-tests were used to compare the patient tumors and the normal controls at the same area. Only ALFF (and that with Z-standardization) along with VMHC succeeded in differentiating significant differences between tumors and the sham tumors areas of normal controls. This study tested the premise of R-fMRI biomarkers for differentiating lesions, and brings a new understanding to physical significance of the Z-standardization.

neuroscience↗