In cancer cells, increased ROS generation, which results from elevated metabolic activity and mitochondrial dysfunction, contributes to tumor development and progression1,4
June 1, 2021
In cancer cells, increased ROS generation, which results from elevated metabolic activity and mitochondrial dysfunction, contributes to tumor development and progression1,4. by caspase-8 in ROS-induced apoptosis in the HCT116 human colon cancer cell collection. We found that NHLRC2 protein levels were decreased in ROS-induced apoptosis in HCT116 cells. Caspase-8 was identified as the enzyme responsible for the decreased NHLRC2 levels in ROS-induced apoptosis. Furthermore, we show that loss of NHLRC2 resulted in an increased susceptibility of HCT116 cells to ROS-induced apoptosis. Taken together, these results suggest that excess ROS production causes a caspase-8-mediated decrease in NHLRC2 protein levels, leading to apoptotic cell death in colon cancer cells, indicating an important role for NHLRC2 in the regulation of ROS-induced apoptosis. Results The oxidant tBHP reduces NHLRC2 protein levels through ROS production in HCT116 cells To study the potential role of NHLRC2 in ROS-induced apoptosis, we examined the effects of the oxidant gene were not affected by tBHP treatment (Fig.?1d). These results indicated that tBHP treatment induced apoptotic cell death and reduced NHLRC2 protein levels through ROS production in HCT116 cells. Open in a separate windows Fig. 1 The oxidant tBHP reduces NHLRC2 protein levels through ROS production in HCT116 cells a, b Percentages of cells that underwent apoptosis for HCT116 cells treated with tBHP and NAC. a Figures adjacent to the outline show the percentage of cells in each area. b The sum of annexin V+PI? and annexin V+PI+ populations in a is usually represented as the percentage of annexin V+ cells. Data symbolize the imply??SD based on three independent experiments. *gene in HCT116 cells treated with tBHP. The mRNA expression levels of were normalized against those of gene in cattle is related to embryonic malformation. Furthermore, homozygous deletion of the gene in mice yielded an embryonic lethality39. On the other SCR7 pyrazine hand, NHLRC2 was identified as a blood biomarker for Alzheimers disease40. Therefore, it has been indicated that NHLRC2 plays an important role in embryonic development and is related to human diseases. However, the functions and physiological functions of NHLRC2 had been totally unexplored. In this study, we show that NHLRC2 acted as SCR7 pyrazine SCR7 pyrazine an antioxidant protein in the regulation of ROS-induced apoptosis. Furthermore, Muc1 the depletion of NHLRC2 significantly suppressed cell proliferation in HCT116 cells, even in the absence of excessive ROS production. Thus, NHLRC2 may have an additional role in the regulation of cell proliferation, in addition to apoptosis. Here we show that this Trx-like domain name of NHLRC2 interacted with the proenzymes of caspases. In general, the two cysteine residues in the catalytic site of the Trx-like domain name are thought to regulate redox says of thiol groups of proteins19,20. Caspases are a family of cysteine proteases that use a cysteine thiol group in the active site to cleave a peptide bond after an Asp residue of the target protein. SCR7 pyrazine Thus, NHLRC2 may participate in caspase activation by regulating the redox state of the catalytic cysteine thiol group of caspases. NHL-repeat domains have been demonstrated to form -propeller structures23,24 much like those of the WD40-repeat domain name, which is usually involved in proteinCprotein interactions. Many NHL-repeat domain name proteins have additional motifsincluding RING domains, B-box zinc finger domains and coiled-coil domainsindicating their diverse functions in various cellular pathways. For example, NHL-repeat-containing protein 1 (NHLRC1), which is a causative gene for Lafora disease, an autosomal recessive neurodegenerative disorder, encodes an E3 ubiquitin ligase that consists of a RING domain name and an NHL-repeat domain name41,42..