Jolkinolide B induces apoptosis of colorectal carcinoma through ROS-ER stress-Ca2+-mitochondria dependent pathway

Abstract

Colorectal carcinoma (CRC) remains one of the leading causes of death in cancer-related diseases. In this study, we aimed to investigate the anticancer effect of Jolkinolide B (JB), a bioactive diterpenoid component isolated from the dried roots of Euphorbia fischeriana Steud, on CRC cells and its underlying mechanisms. We found that JB suppressed the cell viability and colony formation of CRC cells, HT29 and SW620. Annexin V/PI assay revealed that JB induced apoptosis in CRC cells, which was further confirmed by the increased expression of cleaved-caspase3 and cleaved-PARP. iTRAQ-based quantitative proteomics was performed to identify JB-regulated proteins in CRC cells. Gene Ontology (GO) analysis revealed that these JB-regulated proteins were mainly involved in ER stress response, which was evidenced by the expression of ER stress marker proteins, HSP90, Bip and PDI. Moreover, we found that JB provoked the generation of reactive oxygen species (ROS), and that inhibition of the ROS generation with N-acetyl L-cysteine could reverse the JB-induced apoptosis. Confocal microscopy and flow cytometry showed that JB treatment enhanced intracellular and mitochondrial Ca2+ level and JC-1 assay revealed a loss of mitochondrial membrane potential in CRC after JB treatment. The mitochondrial Ca2+ uptake and depolarization can be blocked by Ruthenium Red (RuRed), an inhibitor of mitochondrial Ca2+ uniporter. Taken together, we demonstrated that JB exerts its anticancer effect by ER stress-Ca2+-mitochondria signaling, suggesting the promising chemotherapeutic potential of JB for the treatment of CRC.

Metabolism of Reactive Oxygen Species in Osteosarcoma and Potential Treatment Applications

“…The intracellular alterations when cells suffer ischaemia, including H + and Ca 2+ accumulation and the corresponding dysfunctions, affect the mitochondrial membrane potential, leading to ROS formation [30,31]. In addition to these points, stress-response pathway activation would be induced by ROS accumulation immediately, and apoptosis would be subsequently increased [32]. Simultaneously, many apoptosis stimuli, including treatment with tumour necrosis factor (TNF)-α [33] and lipopolysaccharide (LPS) [34] and growth factor withdrawal, can induce ROS generation through mitochondria [35].…”

Cultivated and wild Pleurotus ferulae ethanol extracts inhibit hepatocellular carcinoma cell growth via inducing endoplasmic reticulum stress- and mitochondria-dependent apoptosis

“…It has been reported that the mitochondria-dependent apoptotic pathway can be activated by ER stress 20 – 22 . We explored whether the mitochondria-dependent apoptosis of H22 cells induced by PFEE-C and PFEE-W was mediated by ER stress.…”

“…However, cells will activate death programs when UPR fails. Recently, a large body of evidence has been shown that ER stress plays important roles in the induction of apoptosis 20 , 22 , 30 , 31 , which can activate JNK, promote caspase-12 cleavage and increase HSP70 level 32 – 34 . JNK can regulate some BCL-2 family proteins such as phosphorylation of Bcl-2 and Bim to cause Δψ m reduction, promote cytochrome c release and induce apoptosis 35 , 36 .…”

Curcumol Overcomes TRAIL Resistance of Non‐Small Cell Lung Cancer by Targeting NRH:Quinone Oxidoreductase 2 (NQO2)

“…Then the mixed protein samples were subjected to the in-solution digestion as previously described. [15,41] The digested peptides were desalinated using a MonoTIPTM C18 Pipette Tip (GL Sciences, Tokyo, Japan) and then analyzed with an Orbitrap Fusion Lumos mass spectrometer (Thermo Fisher Scientific) as previously described. [42] The raw MS data files were searched against UniProt-Swiss Human database (2017_03 Release) using Proteome Discoverer v2.1 (Thermo Fisher Scientific).…”