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This study aimed to assess the impact of conditioned medium from epidermal neural crest stem cells (EPI-NCSCs-CM) on functional recovery following spinal cord injury (SCI), while also exploring the involvement of the PI3K-AKT signaling pathway in regulating neuronal apoptosis. EPI-NCSCs were isolated from 10-day-old Sprague-Dawley rats and cultured for 48 h to obtain EPI-NCSC-CM. SHSY-5Y cells were subjected with H 2 O 2 treatment to induce apoptosis. Cell viability and survival rates were evaluated using the CCK-8 assay and calcein-AM/PI staining. SCI contusion model was established in adult Sprague-Dawley rats to assess functional recovery, utilizing the Basso, Beattie and Bresnahan (BBB) scoring system, inclined test, and footprint observation. Neurological restoration after SCI was analyzed through electrophysiological recordings. Histological analysis included hematoxylin and eosin (H&E) staining and Nissl staining to evaluate tissue organization. Apoptosis and oxidative stress levels were assessed using TUNEL staining and ROS detection methods. Additionally, western blotting was performed to examine the expression of apoptotic markers and proteins related to the PI3K/AKT signaling pathway. EPI-NCSC-CM significantly facilitated functional and histological recovery in SCI rats by inhibiting neuronal apoptosis through modulation of the PI3K/AKT pathway. Administration of EPI-NCSCs-CM alleviated H2O2-induced neurotoxicity in SHSY-5Y cells in vitro. The use of LY294002, a PI3K inhibitor, underscored the crucial role of the PI3K/AKT signaling pathway in regulating neuronal apoptosis. This study contributes to the ongoing exploration of molecular pathways involved in spinal cord injury (SCI) repair, focusing on the therapeutic potential of EPI-NCSC-CM. The research findings indicate that EPI-NCSC-CM exerts a neuroprotective effect by suppressing neuronal apoptosis through activation of the PI3K/AKT pathway in SCI rats. These results highlight the promising role of EPI-NCSC-CM as a potential treatment strategy for SCI, emphasizing the significance of the PI3K/AKT pathway in mediating its beneficial effects., (© 2024. The Author(s).)

Although pectin oligosaccharide (POS) can inhibit the growth and proliferation of gastric, colon, prostate, breast, melanoma, and leukemia cells, its effect on bladder cancer remains unknown. Therefore, screening and identification of factors associated with the sensitivity of bladder cancer to drugs and elucidation of their molecular mechanisms will help provide a theoretical basis for establishing postoperative systemic chemotherapy for patients with bladder cancer. We showed that POS promoted the apoptosis of bladder cancer cells, and this finding was consistent with enhanced α2,6-sialylation post-modification. Moreover, POS activated the Hedgehog pathway, the inhibition of which regulated the tumorigenicity of bladder cancer cells in vivo. These findings were consistent with our results in vitro. We conclude that POS promotes the apoptosis of bladder cancer and offers new insights and evidence for the development of individualized treatment strategies. Schema of molecular events underlying POS-induced inhibition of bladder cancer cell proliferation., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

B-cell receptor-associated protein 31 (BAP31) is a ubiquitously expressed endoplasmic reticulum (ER) membrane protein that has been found to be overexpressed in gastric intestinal-type adenocarcinoma. We first studied the relationship of BAP31 with 84 kinds of tumor-associated antigens and found that BAP31 can specifically interact with and regulate the proteasome degradation of the cyclin kinase inhibitor p27 kip1 , which is one of the most frequently dysregulated tumor suppressor proteins in human cancers. Therefore, we screened antibodies against BAP31 from a human VH single-domain antibody library and expressed the antibodies intracellularly. It was found that one of the intrabodies (VH-D1) specifically inhibited p27 kip1 proteasome degradation, possibly by blocking the combination of BAP31 with p27 kip1 . VH-D1 displayed therapeutic effects, as it was able to reduce the growth of human gastric cancer (GC) cell xenografts in nude mice. This effect was due to inhibition of the proliferation and subsequent activation of caspase-dependent apoptosis. Thus, BAP31 is a potential target for the suppression of GC via an intrabody-based approach., (© 2018 UICC.)

The host innate immune response to viral infections often involves the activation of parallel pattern recognition receptor (PRR) pathways that converge on the induction of type I interferons (IFNs). Several viruses have evolved sophisticated mechanisms to attenuate antiviral host signaling by directly interfering with the activation and/or downstream signaling events associated with PRR signal propagation. Here we show that the 3C(pro) cysteine protease of coxsackievirus B3 (CVB3) cleaves the innate immune adaptor molecules mitochondrial antiviral signaling protein (MAVS) and Toll/IL-1 receptor domain-containing adaptor inducing interferon-beta (TRIF) as a mechanism to escape host immunity. We found that MAVS and TRIF were cleaved in CVB3-infected cells in culture. CVB3-induced cleavage of MAVS and TRIF required the cysteine protease activity of 3C(pro), occurred at specific sites and within specialized domains of each molecule, and inhibited both the type I IFN and apoptotic signaling downstream of these adaptors. 3C(pro)-mediated MAVS cleavage occurred within its proline-rich region, led to its relocalization from the mitochondrial membrane, and ablated its downstream signaling. We further show that 3C(pro) cleaves both the N- and C-terminal domains of TRIF and localizes with TRIF to signalosome complexes within the cytoplasm. Taken together, these data show that CVB3 has evolved a mechanism to suppress host antiviral signal propagation by directly cleaving two key adaptor molecules associated with innate immune recognition.

Dietary flavonols have been found to possess preventive and therapeutic potential against several kinds of cancers. This study is conducted to investigate the anti-proliferation effects of kaempferol, a major component of food flavonols, against colon cancer cells. In the human HCT116 colon cancer cell line, kaempferol induced p53-dependent growth inhibition and apoptosis. Furthermore, kaempferol was found to induce cytochrome c release from mitochondria and activate caspase-3 cleavage. The Bcl-2 family proteins including PUMA were involved in this process. Kaempferol also induced ATM and H2AX phosphorylation in HCT116 cells, inhibition of ATM by a chemical inhibitor resulted in abrogation of the downstream apoptotic cascades. These findings suggest kaempferol could be a potent candidate for colorectal cancer management.

Given the rapidly aging population, aging-related diseases are becoming an excessive burden on the global healthcare system. Metformin has been shown to be beneficial to many age-related disorders, as well as increase lifespan in preclinical animal models. During the aging process, kidney function progressively declines. Currently, whether and how metformin protects the kidney remains unclear. In this study, among longevity drugs, including metformin, nicotinamide, resveratrol, rapamycin, and senolytics, we unexpectedly found that metformin, even at low doses, exacerbated experimentally-induced acute kidney injury (AKI) and increased mortality in mice. By single-cell transcriptomics analysis, we found that death of renal parenchymal cells together with an expansion of neutrophils occurs upon metformin treatment after AKI. We identified programmed cell death by ferroptosis in renal parenchymal cells and blocking ferroptosis, or depleting neutrophils protects against metformin-induced nephrotoxicity. Mechanistically, upon induction of AKI, ferroptosis in renal parenchymal cells initiates the migration of neutrophils to the site of injury via the surface receptor CXCR4–bound to metformin–iron–NGAL complex, which results in NETosis aggravated AKI. Finally, we demonstrated that reducing iron showed protective effects on kidney injury, which supports the notion that iron plays an important role in metformin-triggered AKI. Taken together, these findings delineate a novel mechanism underlying metformin-aggravated nephropathy and highlight the mechanistic relationship between iron, ferroptosis, and NETosis in the resulting AKI. [ABSTRACT FROM AUTHOR]

The expression of B-cell receptor associated protein 31 (BAP31) is increased in many tumor types, and it is reported to participate in proliferation, migration, and apoptosis. However, the relationship between BAP31 and chemoresistance is uncertain. This study investigated the role of BAP31 in regulating the doxorubicin (Dox) resistance of hepatocellular carcinoma (HCC). The expression of proteins was assessed by Western blotting. The correlation between BAP31 expression and Dox resistance was examined by MTT and colony formation assays. Apoptosis was analyzed by flow cytometry and TdT-mediated dUTP nick end labeling assays. Western blot and immunofluorescence analyses were performed in the knockdown cell lines to explore the possible mechanisms. In this study, BAP31 was strongly expressed, and knockdown of BAP31 increased Dox chemosensitivity in cancer cells. Furthermore, the expression of BAP31 was higher in the Dox-resistant HCC cells than that in their parental cells; knockdown of BAP31 reduced the half maximal inhibitory concentration value and overcame Dox resistance in Dox-resistant HCC cells. In HCC cells, knockdown of BAP31 increased Dox-induced apoptosis and enhanced Dox chemosensitivity in vitro and in vivo. The potential mechanism by which BAP31 increased Dox-induced apoptosis is that BAP31 inhibited survivin expression by promoting FoxO1 nucleus–cytoplasm translocation. Knockdown of BAP31 and survivin had a synergistic effect on Dox chemosensitivity by enhancing the apoptosis of HCC cells. These findings reveal that BAP31 knockdown enhances Dox chemosensitivity through the downregulation of survivin, suggesting that BAP31 is a potential therapeutic target for improving the treatment response of HCC with resistance to Dox. [ABSTRACT FROM AUTHOR]

Colorectal cancer is the third most malignant cancer occurring around the world. Effective prevention and treatment have been increasingly the focus of global attention. Long‐term diet of fermented dairy inhibits proliferation of colon cancer cell, which is considered that not only live lactic acid bacteria but also the secreted exopolysaccharides exert the function. In this scenario, this study aimed to investigate the mechanism of growth inhibition on HT‐29 cells induced in vitro by exopolysaccharides isolated from Lactobacillus paracasei subsp. paracasei M5L (M5‐EPSs). HT‐29 cells which were treated by a set of concentrations of M5‐EPSs have been investigated of cell viability, characteristic changes, cell cycle distribution, and redox system. The results demonstrated that M5‐EPSs treatments induced HT‐29 cell apoptosis and resulted in upregulation of ROS levels and downregulation of antioxidant enzyme activities, leading to an imbalance in the oxidation system in HT‐29 cells. In response to M5‐EPSs, endogenous ER stress (ERS) markers, including GRP78, ATF4, and CHOP, were transcriptionally altered so that activating the ERS in HT‐29 cells. After NAC treatment, the oxidative stress was inhibited, and the expression of GRP78 and CHOP was significantly decreased, indicating that oxidative stress can significantly affect the ERS pathway. Furthermore, it suggested that the occurrence of apoptosis was associated with Bcl‐2 gene family. In conclusion, this study demonstrated that M5‐EPSs can induce HT‐29 cells apoptosis by destroying the redox system through activation of the ERS signaling pathway. [ABSTRACT FROM AUTHOR]

Ecotropic viral integration site-1 (EVI-1) is an important transcription factor involved in oncogenesis. Aberrant EVI-1 expression has been reported to be a characteristic of multiple types of malignancies; however, very little is known about how EVI-1 regulates breast cancer. Current knowledge of how target genes mediate the biological function of EVI-1 remains limited. In the present study, overexpression of EVI-1 promoted cell proliferation, migration, and invasion, and inhibited apoptosis in breast cancer. By contrast, silencing of EVI-1 inhibited cell proliferation, migration and invasion, and enhanced apoptosis in breast cancer. In addition, the results also revealed that the aberrant expression of EVI-1 regulates genes associated with the apoptotic pathway in breast cancer. Furthermore, EVI-1 was also likely to target the promoter region of calreticulin (CRT) in vitro. It was concluded that EVI-1 can affect epithelial mesenchymal transition-associated genes by regulating the expression of CRT in breast cancer. The results revealed that EVI-1 may be a potential effective therapeutic target in breast cancer. [ABSTRACT FROM AUTHOR]

Purpose: Breast cancer stem cells (BCSCs) have been regarded as the key factor for treatment failure in breast cancer. The abnormal expression of miRNAs plays a significant role in different tumor types. However, the role of miR-1 in breast cancer remains poorly understood. The purpose of this study was to evaluate the effects of miR-1 on the proliferation and apoptosis of BCSCs. Materials and methods: CD44+/CD24-/low/epithelial-specific antigen+ BCSCs were isolated by flow cytometry. Real-time PCR and Western blotting were used to determine the expression of miRNAs, mRNAs, and epithelial–mesenchymal transition (EMT)-related genes. Cell proliferation and apoptosis were measured using the Cell Counting Kit-8 assay and Annexin V-fluorescein isothiocyanate flow cytometry, respectively. Luciferase reporter assay was used to verify whether miR-1 targeted ecotropic virus integration-1 (EVI-1). The role of miR-1 in breast cancer in vivo was evaluated using BCSCs xenograft mouse models. Results: In this study, we demonstrated that miR-1 was significantly downregulated in breast cancer tissues compared to the adjacent non-tumor tissues. The luciferase reporter assay verified that EVI-1 was a direct target of miR-1, and upregulation of miR-1 negatively correlated with the expression of EVI-1 in BCSCs at both the transcriptional and posttranslational levels. Furthermore, overexpression of miR-1 inhibited BCSCs proliferation and promoted apoptosis, which was reversed by the overexpression of EVI-1. In addition, we demonstrated that aberrant expression of miR-1 could regulate EMT-related genes in BCSCs. Finally, immunohistochemical staining demonstrated that EVI-1 expression was decreased in BCSCs tumors following intratumoral miR-1 agomir treatment compared to the control group. Conclusion: miR-1 can negatively regulate the expression of EVI-1 and, thus, affect BCSCs proliferation, apoptosis, and EMT-related markers. Taken together, these findings demonstrate that miR-1 could be employed as a therapeutic strategy in the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

DNA damage-induced activation of the transcription factor NF-κB plays an important role in the cellular response to genotoxic stress. However, uncontrolled NF-κB activation upon DNA damage may lead to deleterious consequences. Although the mechanisms mediating genotoxic NF-κB activation have been elucidated, how this signalling is terminated remains poorly understood. Here, we show that the CCCH-type zinc finger-containing protein MCPIP1 (monocyte chemotactic protein-1-induced protein-1; also known as ZC3H12A) is induced upon genotoxic treatment in an NF-κB-dependent manner. MCPIP1 upregulation reduces NEMO linear ubiquitylation, resulting in decreased activation of IKK and NF-κB. NEMO ubiquitylation is decreased through the deubiquitinase USP10, which interacts with NEMO via MCPIP1 upon genotoxic stress. USP10 association with NEMO leads to removal of NEMO-attached linear polyubiquitin chains and subsequent inhibition of the genotoxic NF-κB signalling cascade. Consistently, USP10 is required for MCPIP1-mediated inhibition of genotoxic NF-κB activation and promotion of apoptosis. Thus, by mediating USP10-dependent deubiquitination of NEMO, MCPIP1 induction serves as a negative feedback mechanism for attenuating genotoxic NF-κB activation. [ABSTRACT FROM AUTHOR]

Background: Cancer stem cells are regarded as the origin of tumors that can proliferate, relapse, and metastasize. Nanog, with its capacity to maintain the pluripotency and regulate proliferation and prevent differentiation, is one of the most important core markers of cancer stem cells. Studying the role of Nanog in esophageal squamous cell carcinoma (ESCC), therefore, has important implications. Methods: In the present study, we first detected the expression of Nanog in the ESCC and cell lines by RT-PCR, immunofluorescence, and immunohistochemisty. Then, we used small interfering RNA (siRNA) to block Nanog expression while evaluating the effect of Nanog siRNA on cell apoptosis and the combined effects with Cisplatin in ESCC cell lines. Results: The results showed that both mRNA and protein-level Nanog are overexpressed in ESCC tissues compared with their normal counterparts, and the increased occurrence of Nanog expression was positively correlated with TNM stages and histopathological differentiation of ESCC patients ( p < 0.01). At the same time, Nanog siRNA efficiently decreased Nanog expression and induced cell apoptosis. Treatment with Nanog siRNA in combination with Cisplatin, therefore, enhanced chemosensitivity. Conclusion: The present study's results suggest that detecting Nanog might be helpful for diagnosing ESCC, and Nanog siRNA combined with Cisplatin may be a feasible strategy to enhance the sensitivity of chemotherapy in patients with ESCC. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) affects elderly population worldwide and endoplasmic reticulum (ER) stress is known to be positively correlated with OA development. Previous reports prove the cytoprotective effects of baicalin on chondrocytes, whereas the mechanisms are hardly reported. Hence, we aimed to investigate the links between OA, ER stress, and baicalin. Chondrocytes from patients with OA were subjected to H2O2 treatment with or without baicalin pretreatment, and cell viability was assessed via Cell Counting Kit-8. Messenger RNA (mRNA) amounts of apoptosis-related genes (Bax, Bcl-2, and Caspase-3), extracellular matrix (ECM)-related genes (Collange I, Collange II, Aggrecan, and Sox9) and ER stress hallmarks (binding immunoglobulin protein [BiP] C/EBP homologous protein [CHOP]) were evaluated via quantitative real-time PCR. Bax, Bcl-2, BiP, and CHOP protein levels were analyzed via Western blot. Baicalin suppressed the changes in cell viability and apoptosis-related gene expressions caused by H2O2. Reactive oxygen species and glutathione/oxidized glutathione assay showed that H2O2 enhanced oxidative stress. Baicalin suppressed H2O2-induced downregulation of mRNA expression of ECM-related genes. Moreover, baicalin reduced H2O2-stimulated increase in oxidative stress and the expression of ER stress hallmarks. Endoplasmic reticulum stress inducer abolished the protective activities, whereas ER stress inhibitor did not exhibit extra protective effects. Baicalin pretreatment protected patient-derived chondrocytes from H2O2 through ER stress inhibition. [ABSTRACT FROM AUTHOR]