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Dysfunctional renal tubular epithelial cells, induced by high glucose, are commonly observed in the kidney tissues of diabetic nephropathy (DN) patients. The epithelial-mesenchymal transition (EMT) of these cells often leads to renal interstitial fibrosis and kidney damage in DN. High glucose also triggers mitochondrial damage and apoptosis, contributing further to the dysfunction of renal tubular epithelial cells. Cellular senescence, a recognized characteristic of DN, is primarily caused by high glucose. However, it remains unclear whether high glucose-induced cellular senescence in DN exacerbates the functional impairment of tubular epithelial cells. In this study, we examined the relationship between EMT and cellular senescence in kidney tissues from streptozotocin (STZ)-induced DN and HK-2 cells treated with high glucose (HG). We also investigated the impact of HG concentrations on tubular epithelial cells, specifically mitochondrial dysfunction, cellular senescence and apoptosis. These damages were primarily associated with the secretion of cytokines (such as IL-6, and TNF-α), production of reactive oxygen species (ROS), and an increase of intracellular Ca 2+ . Notably, resveratrol, an anti-aging agent, could effectively attenuate the occurrence of EMT, mitochondrial dysfunction, and apoptosis induced by HG. Mechanistically, anti-aging treatment leads to a reduction in cytokine secretion, ROS production, and intracellular Ca 2+ levels., Competing Interests: Declaration of competing interest All authors declare no competing interests. We declare that neither the entire paper nor any part of its content has been published or has been accepted elsewhere. If accepted, it will not be published elsewhere in the same form, in English or in any other languages, including electronic form without the written consent of the copyright-holder., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

v-myc avian myelocytomatosis viral oncogene homolog (c-Myc) is an important member protein of the Myc family that is important in cell cycle progression, apoptosis and tumorigenesis. In the present study, the role of c‑Myc in rhabdomyosarcoma (RMS) was assessed. Firstly, expression of endogenous c‑Myc and cyclin dependent kinase inhibitor 1A (p21) was examined in normal skeletal muscle, RMS specimens and TE671 RMS cells by immunohistochemistry, reverse transcription‑quantitative polymerase chain reaction and western blotting. Furthermore, cell cycle progression and apoptosis were assessed in TE671 RMS cells following treatment with a c‑Myc inhibitor, 10058‑F4. The results demonstrated that c‑Myc was overexpressed in clinical RMS tissues and TE671 cells, with the highest expression observed in the most RMS samples. Expression of p21 protein and apoptosis function were increased following treatment with 10058‑F4, but no difference was observed in cell cycle progression. In conclusion, the present study indicated that c‑Myc promotes RMS development by inhibiting apoptosis through repression of p21 transcription. Further studies will be required to evaluate c‑Myc as a target for RMS clinical treatment.

Background: Acquired imatinib (IM) resistance is frequently characterized by Bcr-Abl mutations that affect IM binding and kinase inhibition in patients with chronic myelogenous leukemia (CML). Bcr-Abl-T315I mutation is the predominant mechanism of the acquired resistance to IM. Therefore, it is urgent to search for additional approaches and targeting strategies to overcome IM resistance. We recently reported that nickel pyrithione (NiPT) potently inhibits the ubiquitin proteasome system via targeting the 19S proteasome-associated deubiquitinases (UCHL5 and USP14), without effecting on the 20S proteasome. In this present study, we investigated the effect of NiPT, a novel proteasomal deubiquitinase inhibitor, on cell survival or apoptosis in CML cells bearing Bcr-Abl-T315I or wild-type Bcr-Abl., Methods: Cell viability was examined by MTS assay and trypan blue exclusion staining assay in KBM5, KBM5R, K562, BaF3-p210-WT, BaF3-p210-T315I cells, and CML patients' bone marrow samples treated with NiPT. Cell apoptosis in CML cells was detected with Annexin V-FITC/PI and rhodamine-123 staining followed by fluorescence microscopy and flow cytometry and with western blot analyses for apoptosis-associated proteins. Expression levels of Bcr-Abl in CML cells were analyzed by using western blotting and real-time PCR. The 20S proteasome peptidase activity was measured using specific fluorogenic substrate. Active-site-directed labeling of proteasomal DUBs, as well as the phosphorylation of USP14 was used for evaluating the inhibition of the DUBs activity by NiPT. Mouse xenograft models of KBM5 and KBM5R cells were analyzed, and Bcr-Abl-related proteins and protein biomarkers related to proliferation, differentiation, and adhesion in tumor tissues were detected by western blots and/or immunohistological analyses., Results: NiPT induced apoptosis in CML cells and inhibited the growth of IM-resistant Bcr-Abl-T315I xenografts in nude mice. Mechanistically, NiPT induced decreases in Bcr-Abl proteins, which were associated with downregulation of Bcr-Abl transcription and with the cleavage of Bcr-Abl protein by activated caspases. NiPT-induced ubiquitin proteasome system inhibition induced caspase activation in both IM-resistant and IM-sensitive CML cells, and the caspase activation was required for NiPT-induced Bcr-Abl downregulation and apoptotic cell death., Conclusions: These findings support that NiPT can overcome IM resistance through both Bcr-Abl-dependent and Bcr-Abl-independent mechanisms, providing potentially a new option for CML treatment.

Resistance to chemotherapy is a great challenge to improving the survival of patients with diffuse large B-cell lymphoma (DLBCL), especially those with activated B-cell-like DLBCL (ABC-DLBCL). Therefore it is urgent to search for novel agents for the treatment of DLBCL. Gambogic acid (GA), a small molecule derived from Chinese herb gamboges, has been approved for Phase II clinical trial for cancer therapy by Chinese FDA. In the present study, we investigated the effect of GA on cell survival and apoptosis in DLBCL cells including both GCB- and ABC-DLBCL cells. We found that GA induced growth inhibition and apoptosis of both GCB- and ABC-DLBCL cells in vitro and in vivo, which is associated with proteasome malfunction. These findings provide significant pre-clinical evidence for potential usage of GA in DLBCL therapy particularly in ABC-DLBCL treatment.

Resistance to Imatinib mesylate (IM) is an emerging problem for patients with chronic myelogenous leukemia (CML). T315I mutation in the Bcr-Abl is the predominant mechanism of the acquired resistance to IM and second generation tyrosine kinase inhibitors (TKI). Therefore it is urgent to search for new measures to overcome TKI-resistance. Auranofin (AF), clinically used to treat rheumatic arthritis, was recently approved by US Food and Drug Administration for Phase II clinical trial to treat cancer. In contrast to the reports that AF induces apoptosis by increasing intracellular reactive oxygen species (ROS) levels via inhibiting thioredoxin reductase, our recent study revealed that AF-induced apoptosis depends on inhibition of proteasomal deubiquitinases (UCHL5 and USP14). Here we report that (i) AF induces apoptosis in both Bcr-Abl wild-type cells and Bcr-Abl-T315I mutation cells and inhibits the growth of IM-resistant Bcr-Abl-T315I xenografts in vivo; (ii) AF inhibits Bcr-Abl through both downregulation of Bcr-Abl gene expression and Bcr-Abl cleavage mediated by proteasome inhibition-induced caspase activation; (iii) proteasome inhibition but not ROS is required for AF-induced caspase activation and apoptosis. These findings support that AF overcomes IM resistance through both Bcr/Abl-dependent and -independent mechanisms, providing great clinical significance for cancer treatment.

Spinal cord injury (SCI) is a major cause of disability, and at present, there is no universally accepted treatment. The functional decline following SCI is contributed to both direct mechanical injury and secondary pathophysiological mechanisms that are induced by the initial trauma. These mechanisms initially involve widespread haemorrhage at the site of injury and necrosis of central nervous system (CNS) cellular components. At later stages of injury, the cord is observed to display reactive gliosis. The actions of astrocytes as well as numerous other cells in this response create an environment that is highly nonpermissive to axonal regrowth. Also manifesting important effects is the immune system. The early recruitment of neutrophils and at later stages, macrophages to the site of insult cause exacerbation of injury. However, at more chronic stages, macrophages and recruited T helper cells may potentially be helpful by providing trophic support for neuronal and non-neuronal components of the injured CNS. Within this sea of injurious mechanisms, the oligodendrocytes appear to be highly vulnerable. At chronic stages of SCI, a large number of oligodendrocytes undergo apoptosis at sites that are distant to the vicinity of primary injury. This leads to denudement of axons and deterioration of their conductive abilities, which adds significantly to functional decline. By indulging into the molecular mechanisms that cause oligodendrocyte apoptosis and identifying potential targets for therapeutic intervention, the prevention of this apoptotic wave will be of tremendous value to individuals living with SCI.

Background Aberrant expression of mucins can promote the epithelial-mesenchymal transition (EMT), which leads to enhanced tumorigenesis. Carcinogenesis-related pathways involving c-MET and β-catenin involve mucins. Among the mucins, MUC5AC and MUC6 are characteristic for stomach mucins. This study characterized expressions of MET, MUC5AC, MUC5B, and MUC6 EMT signaling in human gastric cancer (GC) cell lines, and further characterized the differential susceptibility of these cell lines to tepotinib. Methods We assessed the antitumor activity of tepotinib in GC cell lines. The effect of tepotinib on cell viability (IC50), apoptotic cell death, the EMT, and c-MET and β-catenin signaling were evaluated by MTS, flow cytometry, western blotting, and qRT-PCR. Antitumor efficacy was assessed in MKN45 xenograft mice. Results Tepotinib treatment showed dose-dependent growth inhibition of c-MET-amplified SNU620, MKN45, and KATO III cells with concomitant induction of apoptosis, but tepotinib treatment did not have an effect on c-MET-reduced MKN28 and AGS cells. Tepotinib treatment also significantly reduced expressions of phosphor-c-MET, total c-MET, phosphor-ERK, total ERK, beta-catenin, and c-MYC protein in SNU620 and MKN45 cells. In contrast, this drug was only slightly active against KATO III cells. Notably, tepotinib significantly reduced the expressions of EMT promotion genes such as MMP7, COX-2, WNT1, MUC5B, and c-MYC in c-MET-expressed GC cells, and increased expressions of EMT suppression genes such as MUC5AC, MUC6, GSK3β, and ECAD. In a murine xenograft model, tumor volumes were significantly reduced in the tepotinib-treated group, when administered by daily oral gavage at a dose of 10 mg/kg/day. Histologically, tepotinib induced more necrosis than in the control group. Conclusions These results are consistent with clinical evaluations of tepotinib in c-MET and MUC5B-expressed GCs. Editorial acknowledgement National R&D Program for Cancer Control, Ministry of Health and Welfare (HA17C0054), the National Research Foundation of Korea grant funded by the Korean Ministry of Science and ICT (NRF-2017R1A2B4005055), the Ministry of Food and Drug Safety (awarded in 2018, 18183MFDS491) of Korea, the Hallym University Medical Center Research Fund, and the Hallym University Internal Translational Research Fund (No. HURF-2015-38). Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]