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The Biological Function of POLA2 in Hepatocellular Carcinoma.

The role and prognostic value of POLA2 in liver cancer were comprehensively analyzed through TCGA, GEO, and ICGC databases, and the role of POLA2 in liver cancer cells and the regulatory mechanism involved were further verified through cell experiments. Hepatocellular carcinoma (HCC) is the most prevalent malignancy with high morbidity and mortality. Consequently, it is critical to identify robust and reliable predictive biomarkers and therapeutic targets for HCC patients. POLA2 is involved in the regulation of various tumors, but the specific role of POLA2 in HCC has not been reported. The regulatory role and prognostic value of POLA2 in HCC were determined by bioinformatics techniques and cell experiments. The specific role and prognostic value of POLA2 in HCC were comprehensively analyzed by combining the expression data of POLA2 in TCGA, GEO, and ICGC databases and clinical data. In clinical samples, the expression of POLA2 in liver cancer was verified by QPCR. Further, the regulatory role of POLA2 in HCC was explored through cell experiments such as CCK-8, clonal formation experiment, EDU cell proliferation experiment, and flow cytometry. In terms of mechanism exploration, western blot was used to verify the specific regulatory mechanism that POLA2 participated in. Finally, the relationship between POLA2 and immune invasion of HCC was analyzed by using the TIMER database. A POLA2 expression and prognosis analysis of HCC patients was conducted using the TCGA, GEO, and ICGC databases. We hypothesized that POLA2 might be one of the key factors contributing to the HCC progression. According to a combined analysis of TCGA, ICGC, and GEO databases, POLA2 was highly expressed in HCC. This was further confirmed in clinical samples using the qPCR. POLA2 knockdown was also performed in vitro on HCC cell lines to study the changes in their biological behavior. We confirmed that POLA2 was associated with HCC proliferation by CCK-8, Colony Formation, and EDU assay. We verified the POLA2's involvement in cell cycle regulation using flow techniques. The relationship between POLA2 and PI3K/AKT/mTOR pathway was explored using Western Blotting experiments regarding its mechanism. Further analysis revealed that the POLA2 expression was significantly associated with HCC immune infiltration. Our study demonstrated POLA2's importance in HCC development and progression and its potential role as a biomarker for disease progression on multiple levels. POLA2 has an important role in regulating the cell cycle and cell proliferation. By interfering with the cell cycle and proliferation, HCC cell growth is inhibited. Furthermore, POLA2 expression was significantly associated with immune infiltration. POLA2 may play a role in HCC immunotherapy based on its correlation with several immune cell types' genetic markers. The findings of this study are expected to lead to new anticancer strategies for HCC.

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RHBDD1 Promotes the Growth and Stemness Characteristics of Gastric Cancer Cells by Activating Wnt/β-catenin Signaling Pathway.

Gastric cancer (GC) is threatening public health, with at least one million new cases reported each year. Rhomboid domain-containing protein 1 (RHBDD1) has been identified to regulate the proliferation, migration, and metastasis of cancer cells. However, the role of RHBDD1 in GC has not been elucidated. This study aimed to investigate the role of RHBDD1 on the growth, metastasis, and stemness characteristics of GC. RHBDD1 expression was analyzed from the TCGA databank. qRT-PCR was conducted to evaluate the transcription level of RHBDD1. Western blots were used to evaluate the protein expression of RHBDD1, CD133, CD44, Nanog, β-catenin and c-myc. Colony formation assay and transwell assay were conducted to evaluate the growth and metastasis of NCI-N87 cells, respectively. Sphere-forming assay was performed to study the stemness characteristics. The nude mice xenotransplantation model and immunohistochemistry (IHC) were performed to evaluate the growth of GC in vivo. Results: RHBDD1 expression is elevated in GC cells and clinical tissues. RHBDD1 expression is positively associated with cell proliferation and metastasis of GC cells. RHBDD1 knockdown suppresses the expression of CD133, CD44 and Nanog and attenuates sphere-forming ability. RHBDD1 activates the Wnt/β-catenin pathway via promoting the expression of β-catenin / c-myc and inducing β-catenin translocation into nuclear. RHBDD1 knockdown inhibits the growth of GC in nude mice xenotransplantation model. RHBDD1 is highly expressed in GC, and its knockdown inhibits the growth, metastasis and stemness characteristics of GC cells through activating the Wnt/β-catenin pathway, suggesting that RHBDD1 has the potential to be a novel therapeutic target for GC treatment.

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RBM7 deficiency promotes breast cancer metastasis by coordinating MFGE8 splicing switch and NF-kB pathway.

Aberrant alternative splicing is well-known to be closely associated with tumorigenesis of various cancers. However, the intricate mechanisms underlying breast cancer metastasis driven by deregulated splicing events remain largely unexplored. Here, we unveiled that RBM7 is decreased in lymph node and distant organ metastases of breast cancer as compared to primary lesions and low expression of RBM7 is correlated with the reduced disease-free survival of breast cancer patients. Breast cancer cells with RBM7 depletion exhibited an increased potential for lung metastasis compared to scramble control cells. The absence of RBM7 stimulated breast cancer cell migration, invasion, and angiogenesis. Mechanistically, RBM7 controlled the splicing switch of MFGE8, favoring the production of the predominant isoform of MFGE8, MFGE8-L. This resulted in the attenuation of STAT1 phosphorylation and alterations in cell adhesion molecules. MFGE8-L exerted an inhibitory effect on the migratory and invasive capability of breast cancer cells, while the truncated isoform MFGE8-S, which lack the second F5/8 type C domain had the opposite effect. In addition, RBM7 negatively regulates the NF-κB cascade and an NF-κB inhibitor could obstruct the increase in HUVEC tube formation caused by RBM7 silencing. Clinically, we noticed a positive correlation between RBM7 expression and MFGE8 exon7 inclusion in breast cancer tissues, providing new mechanistic insights for molecular-targeted therapy in combating breast cancer.

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Ginsenoside Rb1 Inhibits the Proliferation of Lung Cancer Cells by Inducing the Mitochondrial-mediated Apoptosis Pathway.

Lung cancer is one of the more common malignant tumors posing a great threat to human life, and it is very urgent to find safe and effective therapeutic drugs. The antitumor effect of ginsenosides has been reported to be a treatment with a strong effect and a high safety profile. This paper aimed to investigate the inhibitory effect of ginsenoside Rb1 on 95D and NCI-H460 lung cancer cells and its pathway to promote apoptosis. We performed the CCK-8 assay, fluorescence staining assay, flow cytometry, scratch healing assay, and Transwell assay to detect the effects of different concentrations of ginsenoside Rb1 on the antitumor activity of 95D and NCI-H460 cells and Western Blot detected the mechanism of antitumor effect. Ginsenoside Rb1 treatment significantly increased the inhibition and apoptosis rates of 95D and NCIH460 cells and inhibited the cell cycle transition from S phase to G2/M. Rb1 induces apoptosis by altering the levels of P53, Bax, Cyto-c, Caspase-8, Caspase-3, Cleaved Caspase-3, Bcl-2, MMP-2, and MMP-9 proteins and activating the external apoptotic pathway. Ginsenoside Rb1 inhibits proliferation and migration and induces apoptosis of 95D and NCI-H460 lung cancer cells by regulating the mitochondrial apoptotic pathway to achieve antitumor activity.

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Combination of betulinic acid and EGFR-TKIs exerts synergistic anti-tumor effects against wild-type EGFR NSCLC by inducing autophagy-related cell death via EGFR signaling pathway

BackgroundEpidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of lung cancer patients with mutated EGFR. However, the efficacy of EGFR-TKIs in wild-type EGFR tumors has been shown to be marginal. Methods that can sensitize EGFR-TKIs to EGFR wild-type NSCLC remain rare. Hence, we determined whether combination treatment can maximize the therapeutic efficacy of EGFR-TKIs.MethodsWe established a focused drug screening system to investigate candidates for overcoming the intrinsic resistance of wild-type EGFR NSCLC to EGFR-TKIs. Molecular docking assays and western blotting were used to identify the binding mode and blocking effect of the candidate compounds. Proliferation assays, analyses of drug interactions, colony formation assays, flow cytometry and nude mice xenograft models were used to determine the effects and investigate the molecular mechanism of the combination treatment.ResultsBetulinic acid (BA) is effective at targeting EGFR and synergizes with EGFR-TKIs (gefitinib and osimertinib) preferentially against wild-type EGFR. BA showed inhibitory activity due to its interaction with the ATP-binding pocket of EGFR and dramatically enhanced the suppressive effects of EGFR-TKIs by blocking EGFR and modulating the EGFR-ATK-mTOR axis. Mechanistic studies revealed that the combination strategy activated EGFR-induced autophagic cell death and that the EGFR-AKT-mTOR signaling pathway was essential for completing autophagy and cell cycle arrest. Activation of the mTOR pathway or blockade of autophagy by specific chemical agents markedly attenuated the effect of cell cycle arrest. In vivo administration of the combination treatment caused marked tumor regression in the A549 xenografts.ConclusionsBA is a potential wild-type EGFR inhibitor that plays a critical role in sensitizing EGFR-TKI activity. BA combined with an EGFR-TKI effectively suppressed the proliferation and survival of intrinsically resistant lung cancer cells via the inhibition of EGFR as well as the induction of autophagy-related cell death, indicating that BA combined with an EGFR-TKI may be a potential therapeutic strategy for overcoming the primary resistance of wild-type EGFR-positive lung cancers.Graphical abstract

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Perceived stress, positive psychological capital and health literacy in patients with multiple chronic conditions: A structural equation modelling.

To investigate the structural relationships among perceived stress (PS), positive psychological capital (PsyCap) and health literacy (HL) in patients with multiple chronic conditions (MCC) and construct a model to explore the relationships of PS and PsyCap on HL. HL is critical in the rehabilitation and management of patients with MCC. Extensive understanding of the relationships between research variables can help nursing staff to implement effective programmes that improve the level of HL of patients. However, currently there is no research that has evaluated the structural relationships among these variables using a single model. This study adhered to the STROBE guidelines for reporting cross-sectional studies. The Health Literacy Scale for Chronic Patients, Chinese Perceived Stress Scale (CPSS) and Positive Psychological Capital Questionnaire were used to assess HL, PS and PsyCap, respectively. Questionnaires were distributed to 317 patients with MCC attending a tertiary general care hospital in China from February to May 2023, using convenience sampling approach. Structural equation modelling was used to validate the proposed model. The findings showed that PS has a negative relationship with HL and PsyCap. PS was indirectly associated with HL through PsyCap. The results indicated that PsyCap was positively associated with HL. The PS and PsyCap explained 64% of the variance in HL. The findings showed that the proposed model had high validity and structural relationships between chosen variables were observed for MCC patients. These results may help nursing staff develop strategies to improve the HL of patients with MCC, which should focus on reducing PS and enhancing PsyCap to improve HL. Nursing staff can provide targeted psychological counselling and health guidance for patients to alleviate negative emotions and further promote their HL. Participate in research and fill out questionnaires.

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Characterizations of gut bacteriome, mycobiome, and virome of healthy individuals living in sea-level and high-altitude areas.

The contribution of gut microbiota to human high-altitude adaptation remains inadequatelyunderstood. Here a comparative analysis of gut microbiota was conducted between healthy individuals living at sealevel and high altitude using deep whole-metagenome shotgun sequencing, to investigate the adaptivemechanisms of gut microbiota in plateau inhabitants. The results showed the gut bacteriomes in high-altitude individuals exhibited greater within-samplediversity and significant alterations in both bacterial compositional and functional profiles when compared to thoseof sea-level individuals, indicating the potential selection of unique bacteria associated with high-altitudeenvironments. The strain-level investigation revealed enrichment of Collinsella aerofaciens and Akkermansiamuciniphila in high-altitude populations. The characteristics of gut virome and gut mycobiome were alsoinvestigated. Compared to sea-level subjects, high-altitude subjects exhibited a greater diversity in their gut virome,with an increased number of viral operational taxonomic units (vOTUs) and unique annotated genes. Finally,correlation analyses revealed 819 significant correlations between 42 bacterial species and 375 vOTUs, while nosignificant correlations were observed between bacteria and fungi or between fungi and viruses. The findings have significantly contributed to an enhanced comprehension of the mechanismsunderlying the high-altitude geographic adaptation of the human gut microbiota.

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PPARγ regulates osteoarthritis chondrocytes apoptosis through caspase-3 dependent mitochondrial pathway

Osteoarthritis (OA) is the most prevalent form of arthritis, characterized by a complex pathogenesis. One of the key factors contributing to its development is the apoptosis of chondrocytes triggered by oxidative stress. Involvement of peroxisome proliferator-activated receptor gamma (PPARγ) has been reported in the regulation of oxidative stress. However, there remains unclear mechanisms that through which PPARγ influences the pathogenesis of OA. The present study aims to delve into the role of PPARγ in chondrocytes apoptosis induced by oxidative stress in the context of OA. Primary human chondrocytes, both relatively normal and OA, were isolated and cultured for the following study. Various assessments were performed, including measurements of cell proliferation, viability and cytotoxicity. Additionally, we examined cell apoptosis, levels of reactive oxygen species (ROS), nitric oxide (NO), mitochondrial membrane potential (MMP) and cytochrome C release. We also evaluated the expression of related genes and proteins, such as collagen type II (Col2a1), aggrecan, inducible nitric oxide synthase (iNOS), caspase-9, caspase-3 and PPARγ. Compared with relatively normal cartilage, the expression of PPARγ in OA cartilage was down-regulated. The proliferation of OA chondrocytes decreased, accompanied by an increase in the apoptosis rate. Down-regulation of PPARγ expression in OA chondrocytes coincided with an up-regulation of iNOS expression, leading to increased secretion of NO, endogenous ROS production, and decrease of MMP levels. Furthermore, we observed the release of cytochrome C, elevated caspase-9 and caspase-3 activities, and reduction of the components of extracellular matrix (ECM) Col2a1 and aggrecan. Accordingly, utilization of GW1929 (PPARγ Agonists) or Z-DEVD-FMK (caspase-3 inhibitor) can protect chondrocytes from mitochondrial-related apoptosis and alleviate the progression of OA. During the progression of OA, excessive oxidative stress in chondrocytes leads to apoptosis and ECM degradation. Activation of PPARγ can postpone OA by down-regulating caspase-3-dependent mitochondrial apoptosis pathway.

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Heme oxygenase-1 is involved in the erastin-induced ferroptosis in acute myeloid leukemia cells

Abstract Emerging evidences have suggested that ferroptosis is one of the targeted mechanisms in tumor therapy. However, whether erastin can induce ferroptosis in acute myeloid leukemia (AML) and the potential mechanisms remains to be explored. CCK8 assay was first used to detect the toxicity of erastin to human promyelocytic leukemia cells (HL60), and the toxicological effect of erastin on HL60 cells performed a significant dose-dependent manner. Ferroptosis in HL60 was affirmed through the manifestation of mitochondrial ultrastructural damage, accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), depletion of glutathione (GSH) and glutathione peroxidase (GPX)4. Proteomics analysis identified heme oxygenase-1 (HO-1) as a key protein involved in the ferroptosis pathway. Further experiments showed that activation of HO-1 with Hemin worsened erastin-induced ferroptosis, while inhibition of HO-1 with Znpp partially alleviated it , without affecting protein levels of P62, LC3B, and nuclear receptor coactivator (NCOA)4. Thus, our study has indicated that erastin significantly induced ferroptosis in HL60 cells, which can be reversed by ferrostatin-1 (Fer-1). Overexpression of HO-1 deteriorates erastin-induced ferroptosis, which can be partially alleviated by inhibition of HO-1 independent on ferritinophagy. Ferroptosis, as a new cell death mechanism, may provide new clues and strategies for the treatment of AML.

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