Hypoxia-induced ROS aggravate tumor progression through HIF-1α-SERPINE1 signaling in glioblastoma

Hypoxia,as an important hallmark of the tumor microenvironment,is a major cause of oxidative stress and plays a central role in various malignant tumors,including glioblastoma.Elevated reactive oxygen species(ROS)in a hypoxic microenvironment promote glioblastoma progression;however,the underlying mechanism has not been clarified.Herein,we found that hypoxia promoted ROS production,and the proliferation,migration,and invasion of glioblastoma cells,while this promotion was restrained by ROS scavengers N-acetyl-L-cysteine(NAC)and diphenyleneiodonium chloride(DPI).Hypoxia-induced ROS activated hypoxia-inducible factor-1α(HIF-1α)signaling,which enhanced cell migration and invasion by epithelial-mesenchymal transition(EMT).Furthermore,the induction of serine protease inhibitor family E member 1(SERPINE1)was ROS-dependent under hypoxia,and HIF-1αmediated SERPINE1 increase induced by ROS via binding to the SERPINE1 promoter region,thereby facilitating glioblastoma migration and invasion.Taken together,our data revealed that hypoxia-induced ROS reinforce the hypoxic adaptation of glioblastoma by driving the HIF-1α-SERPINE1 signaling pathway,and that targeting ROS may be a promising therapeutic strategy for glioblastoma.

Reduced cell invasion may be a characteristic of placental defects in pregnant women of advanced maternal age at single-cell level

The mechanisms underlying pregnancy complications caused by advanced maternal age(AMA)remain unclear.We analyzed the cellular signature and transcriptomes of human placentas in AMA women to elucidate these mechanisms.Placental tissues from two AMA women and two controls were used for single-cell RNA-sequencing(scRNA-seq).Controls consisted of AMA women who did not experience any pregnancy complications and pregnant women below the age of 35 years without pregnancy complications.Trophoblast cells were obtained from the placentas of another six pregnant women(three AMA women and three controls),and in-vitro transwell assays were conducted to observe the cell invasion ability.Thirty additional samples(from 15 AMA women and 15 controls)were analyzed to verify the specific expression of serine protease inhibitor clade E member 1(SERPINE1).Preliminary study of the role of SERPINE1 in cell invasion was carried out with HTR8-S/Vneo cells.High-quality transcriptomes of 27607 cells were detected.Three types of trophoblast cells were detected,which were further classified into eight subtypes according to differences in gene expression and Gene Ontology(GO)function.We identified 110 differentially expressed genes(DEGs)in trophoblast cells between the AMA and control groups,and the DEGs were enriched in multiple pathways related to cell invasion.In-vitro transwell assays suggested that the invading trophoblast cells in AMA women were reduced.SERPINE1 was specifically expressed in the trophoblast,and its expression was higher in AMA women(P<0.05).Transfection of human SERPINE1(hSERPINE1)into HTR8-S/Vneo trophoblast cells showed fewer invading cells in the hSERPINE1 group.Impaired cell invasion may underlie the increased risk of adverse pregnancy outcomes in AMA women.Abnormal expression of SERPINE1 in extravillous trophoblast(EVT)cells appears to play an important role.